Surgical techniques

Which of the following sutures would be most appropriate for closure of the scrotal skin following an orchidopexy in a 3 year old boy who is otherwise well?

5/0 vicryl 11% 5/0 vicryl rapide✅ 44% 5/0 polypropylene 17% 3/0 vicryl 21% 3/0 silk 7% In children, its always best to use absorbable sutures where possible (removal is a very challenging undertaking). Most surgeons prefer vicryl rapide for this purpose and 5/0 provides adequate strength.

A 40 year old man presents with a long standing inguinal hernia. On examination he has a small, direct inguinal hernia. He inquires as to the risk of strangulation over the next twelve months should he decide not to undergo surgery. Which of the following most closely matches the likely risk of strangulation over the next 12 months?

50% 4% 40% 4% 25% 12% 15% 19% <5%✅ 60% The annual probability of strangulation is up to 3% and is more common in indirect hernias. Elective repair poses few risks. However, emergency repair is associated with increased mortality, particularly in the elderly.

Which of the following sutures has the largest diameter?

6/0 Polypropylene 1% 5/0 Silk 0% 3/0 Nylon 1% 1 Polypropylene✅ 73% 0 Polydiaxone 25% The sizes of suture material are not related to the composition of the suture material.

TEP repair Laparoscopic totally extra peritoneal inguinal hernia repair

A TEP hernia repair is laparoscopic or keyhole surgery that fixes your inguinal hernia from the outside of your peritoneum (the sac that contains all of your abdominal organs) as opposed to inserting instruments through it and performing the repair from inside.

Burst abdomen or dehiscence

A burst abdomen is considered present, when intestine, omentum or other viscera's were seen in the abdominal wound following surgery.

A 67 year old lady undergoes a mastectomy and axillary node clearance for breast cancer. The surgeon decides to insert a drain to prevent the development of a seroma. What is the most appropriate device to use?

A closed suction drainage system made of polypropylene 53% A closed suction drainage system made of latex 15% A passive drainage system made of polypropylene 16% Insertion of a penrose drain 7% Use of a VAC wound closure system 9% Following breast surgery, it is standard practice to use a Redivac type system that is made of polypropylene

A 67 year old lady undergoes a mastectomy and axillary node clearance for breast cancer. The surgeon decides to insert a drain to prevent the development of a seroma. What is the most appropriate device to use?

A closed suction drainage system made of polypropylene 53% A closed suction drainage system made of latex 15% A passive drainage system made of polypropylene 16% Insertion of a penrose drain 7% Use of a VAC wound closure system 9% Following breast surgery, it is standard practice to use a Redivac type system that is made of polypropylene.

mucous fistula

A mucous fistula is a conduit between the skin and a redundant segment of bowel. They are typically constructed because the section of bowel that is exteriorized is at very high risk of breakdown. They are not the same as an end stoma, by definition they are usually seen in patients who have an end stoma. They are typically seen following a sub total colectomy where the distal sigmoid colon is deemed too friable to close and it then brought onto the skin as a mucous fistula.

What is a Wallace Robinsons drain?

A new drainage system, called Robinson after its inventor has demonstrated its efficacy in broad clinical use in general surgery. Particular features of note are an inseparable drain bag unit, a one-way valve eliminating reflux from the bag, a silicon drain which does not block, as well as other useful attributes.

Gases for laparoscopic surgery

Laparoscopic surgery may be performed in a number of body cavities. In some areas irrigation solutions are preferred. In the abdomen insufflation with carbon dioxide gas is commonly used. The amount of gas delivered is adjusted to maintain a constant intra-abdominal pressure of between 12 and 15 mmHg. Excessive intra-abdominal pressure may reduce venous return and lead to hypotension. Too little insufflation will risk obscuring the surgical view.

A 59 year old lady undergoes an exploration of the common bile duct and insertion of a T Tube. Which of the devices listed below would be the most appropriate for this purpose?

Latex T tube on passive drainage 56%✅ Polypropylene T Tube on passive drainage 31% Polypropylene T tube on suction drainage 5% Latex T tube on suction drainage 5% Penrose drain 3% When the decision is made to insert a T Tube following CBD exploration, it is standard practice to use an agent that elicits a fibrotic response to a track will form. Of the agents listed, latex has this property. However, it would not be usual to apply suction to it. A penrose drain would fall out and is not indicated here. Latex tube drains May be shaped (e.g. T Tube) or straight Usually used in non pressurised systems and act as sump drains Most often used when it is desirable to generate fibrosis along the drain track (e.g. following exploration of the CBD)

What type of stoma is most likely to be encountered in a 56 year old man undergoing a low anterior resection for carcinoma of the rectum with a colorectal anastomosis?

Loop ileostomy Colonic resections with an anastomosis below the peritoneal reflection may have an anastomotic leak rate (both clinical and radiological) of up to 15%. Therefore most surgeons will defunction such an anastomosis to reduce the clinical severity of an anastomotic leak. A loop ileostomy will achieve this end point and is relatively easy to reverse. Loop colostomy is less popular in this setting as reversal can compromise the blood supply to the anastomosis

Anastomoses

- A wide variety of anastomoses are constructed in surgical practice. Essentially the term refers to the restoration of luminal continuity. As such they are a feature of both abdominal and vascular surgery. Visceral anastomoses For an anastomosis to heal three criteria need to be fulfilled: Adequate blood supply Mucosal apposition Minimal tension When these are compromised the anastomosis may break down. Even in the best surgical hands some anastomoses are more prone to dehiscence than others. Oesophageal and rectal anastomoses are more prone to leakage and reported leak rates following oesophageal and rectal surgery can be as high as 20%. This figure includes radiological leaks and those with a clinically significant leak will be of a lower order of magnitude. As a rule small bowel anastomoses heal most reliably. The decision as to how best to achieve mucosal apposition is one for each surgeon. Some will prefer the use of stapling devices as they are quicker to use, others will prefer to perform a sutured anastomosis. The attention to surgical technique is more important than the method chosen and a poorly constructed stapled anastomosis in thickened tissue is far more prone to leakage than a hand sewn anastomosis in the same circumstances. If an anastomosis looks unsafe then it may be best not to construct one at all. In colonic surgery this is relatively clear cut and most surgeons would bring out an end colostomy. In situations such as oesophageal surgery this is far more problematic and colonic interposition may be required in this situation. Vascular anastomoses Most arterial surgery involving bypasses or aneurysm repairs will require construction of an arterial anastomosis. Technique is important and for small diameter distal arterial surgery the intimal hyperplasia resulting from a badly constructed anastomosis may render the whole operation futile before the patient leaves hospital. Some key points about vascular anastomoses: Always use non absorbable monofilament suture (e.g. Polypropylene). Round bodied needle. Correct size for anastamosis ( i.e. 6/0 prolene for bottom end of a femoro-distal bypass). Suture should be continuous and from inside to outside of artery to avoid raising an intimal flap.

Surgical site infection

- Surgical site infections may occur following a breach in tissue surfaces and allow normal commensals and other pathogens to initiate infection. They are a major cause of morbidity and mortality. Surgical site infections (SSI) comprise up to 20% of all healthcare associated infections and at least 5% of patients undergoing surgery will develop an SSI as a result. In many cases the organisms are derived from the patient's own body. Measures that may increase the risk of SSI include: Shaving the wound using a razor (disposable clipper preferred) Using a non iodine impregnated incise drape if one is deemed to be necessary Tissue hypoxia Delayed administration of prophylactic antibiotics in tourniquet surgery Preoperatively Don't remove body hair routinely If hair needs removal, use electrical clippers with single use head (razors increase infection risk) Antibiotic prophylaxis if: - placement of prosthesis or valve - clean-contaminated surgery - contaminated surgery Use local formulary Aim to give single dose IV antibiotic on anaesthesia If a tourniquet is to be used, give prophylactic antibiotics earlier Intraoperatively Prepare the skin with alcoholic chlorhexidine (Lowest incidence of SSI) Cover surgical site with dressing A recent meta analysis has confirmed that administration of supplementary oxygen does not reduce the risk of wound infection. In contrast to previous individual RCT's(1) Wound edge protectors do not appear to confer benefit (2) Post operatively Tissue viability advice for management of surgical wounds healing by secondary intention Use of diathermy for skin incisions In the NICE guidelines the use of diathermy for skin incisions is not advocated(3). Several randomised controlled trials have been undertaken and demonstrated no increase in risk of SSI when diathermy is used(4).

Abdominal wound dehiscence

- This is a significant problem facing all surgeons who undertake abdominal surgery on a regular basis. Traditionally, it is said to occur when all layers of an abdominal mass closure fail and the viscera protrude externally (associated with 30% mortality). It can be subdivided into superficial, in which the skin wound alone fails and complete, implying failure of all layers. Factors which increase the risk are: * Malnutrition * Vitamin deficiencies * Jaundice * Steroid use * Major wound contamination (e.g. faecal peritonitis) * Poor surgical technique (Mass closure technique is the preferred method-Jenkins Rule) When sudden full dehiscence occurs the management is as follows: * Analgesia * Intravenous fluids * Intravenous broad spectrum antibiotics * Coverage of the wound with saline impregnated gauze (on the ward) * Arrangements made for a return to theatre Surgical strategy Correct the underlying cause (e.g. TPN or NG feed if malnourished) Determine the most appropriate strategy for managing the wound Options Resuturing of the wound This may be an option if the wound edges are healthy and there is enough tissue for sufficient coverage. Deep tension sutures are traditionally used for this purpose. Application of a wound manager This is a clear dressing with removable front. Particularly suitable when some granulation tissue is present over the viscera or where there is a high output bowel fistula present in the dehisced wound. Application of a 'Bogota bag' This is a clear plastic bag that is cut and sutured to the wound edges and is only a temporary measure to be adopted when the wound cannot be closed and will necessitate a return to theatre for definitive management. Application of a VAC dressing system These can be safely used BUT ONLY if the correct layer is interposed between the suction device and the bowel. Failure to adhere to this absolute rule will almost invariably result in the development of multiple bowel fistulae and create an extremely difficult management problem.

Which of the following sutures is most suitable for the mass closure of an abdominal wall following a laparotomy?

1 polydiaxone 67% 1/0 polydiaxone 20% 2/0 polydiaxone 9% 1/0 silk 3% 1/0 polglactin 2% Suture sizes are assessed on the French gauge scale. 1/0 is thicker than 6/0. Note though that 1 is thicker than 1/0 and 5 is thicker than 1. When the /0 is removed they become thicker with ascending numerical value Only 1 polydiaxone would have sufficient tensile strength.

Which of the following is a permanent suture material best suited for interrupted mattress dermal closure?

2/0 Polydiaxone 13% 3/0 Polydiaxone 16% 4/0 Polyglycolic acid 6% 1/0 Dexon 3% 3/0 Polypropylene 62%✅ Of the sutures listed only prolene is a permanent suture material. It is a good agent for skin closure as it does not incite an inflammatory response and thus provides good cosmesis.

Which of the sutures listed below would be most suitable for the sub cuticular closure of an inguinal hernia repair wound?

2/0 polyglactin 22% 2/0 silk 5% 6/0 polydiaxone 6% 3/0 polydiaxone 62% 1 polydiaxone 5% A 6/0 suture would lack sufficient tensile strength, the other sutures are too thick or otherwise unsuitable.

Which of the following sutures would be most appropriate for securing a chest drain following a thoracotomy?

2/0 silk✅ 71% 4/0 silk 6% 1 polypropylene 11% 1/0 polypropylene 8% 3/0 vicryl rapide 4% Silk is popular for securing drains as it knots reliably and is easy to handle. Silk Braided Biological Theoretically permanent although strength not preserved Anchoring devices, skin closure Knots easily, poor cosmesis

A 34 year old lady is due to undergo a laparoscopic cholecystectomy. Which of the following intrabdominal pressures should typically be set on the gas insufflation system?

4mm Hg 2% 10mm Hg✅ 70% 20mm Hg 20% 40mm Hg 8% 60mm Hg 1% Pressures lower than 7mm Hg are not usually compatible with satisfactory views. Pressures >15mm Hg are usually associated with decreased venous return and hypotension.

Which of the sutures listed below would be most suitable for suturing the femoral artery following an embolectomy?

5/0 polyglactin 4% 5/0 polypropylene 88% 5/0 silk 5% 5/0 polyglyconate 2% 5/0 polyester 2% Vascular sutures should be monofilament and non absorbable. Of the material listed, only polypropylene fulfills this criteria.

Anastomoses

A wide variety of anastomoses are constructed in surgical practice. Essentially the term refers to the restoration of luminal continuity. As such they are a feature of both abdominal and vascular surgery. Visceral anastomoses For an anastomosis to heal three criteria need to be fulfilled: Adequate blood supply Mucosal apposition Minimal tension When these are compromised the anastomosis may break down. Even in the best surgical hands some anastomoses are more prone to dehiscence than others. Oesophageal and rectal anastomoses are more prone to leakage and reported leak rates following oesophageal and rectal surgery can be as high as 20%. This figure includes radiological leaks and those with a clinically significant leak will be of a lower order of magnitude. As a rule small bowel anastomoses heal most reliably. The decision as to how best to achieve mucosal apposition is one for each surgeon. Some will prefer the use of stapling devices as they are quicker to use, others will prefer to perform a sutured anastomosis. The attention to surgical technique is more important than the method chosen and a poorly constructed stapled anastomosis in thickened tissue is far more prone to leakage than a hand sewn anastomosis in the same circumstances. If an anastomosis looks unsafe then it may be best not to construct one at all. In colonic surgery this is relatively clear cut and most surgeons would bring out an end colostomy. In situations such as oesophageal surgery this is far more problematic and colonic interposition may be required in this situation. Vascular anastomoses Most arterial surgery involving bypasses or aneurysm repairs will require construction of an arterial anastomosis. Technique is important and for small diameter distal arterial surgery the intimal hyperplasia resulting from a badly constructed anastomosis may render the whole operation futile before the patient leaves hospital. Some key points about vascular anastomoses: Always use non absorbable monofilament suture (e.g. Polypropylene). Round bodied needle. Correct size for anastamosis ( i.e. 6/0 prolene for bottom end of a femoro-distal bypass). Suture should be continuous and from inside to outside of artery to avoid raising an intimal flap.

Alginate dressings

Alginate dressings absorb wound fluid resulting in gels that maintain a physiologically moist environment and minimize bacterial infections at the wound site.

CLO Test (Campylobacter-like organism)

Also known as CLO test for "Campylobacter-Like Organism", is a rapid urease test (RUT) that accurately detects the urease enzyme of Helicobacter pylori in gastric mucosal biopsies. The test consists of a well of urease indicator gel sealed inside a plastic slide.

A 53 year old man undergoes an elective right hemicolectomy. A stapled ileo-colic anastomosis is constructed. Eight hours later he becomes tachycardic and passes approximately 600ml of dark red blood per rectum. Which of the following processes is the most likely explanation for this occurrence?

Anastomotic leak 11% Discharging mesenteric haematoma 11% Bleeding peptic ulcer 2% Anastomotic staple line bleeding 64%✅ Mesenteric infarct 12% Safe visceral anastamosis requires: Mucosal to mucosal apposition Adequate vascularity Minimal tension Stapled anastomoses are associated with staple line bleeding and this may typically occur in the early post operative phase. They should be managed conservatively as most will settle. Stapled anastomoses are quicker to perform. Ironically, although they may appear easy they can carry considerably more potential pitfalls than their hand sewn equivalent and should be used with caution by the inexperienced, this is especially true if the bowel is very thick walled.

A 68 year old man has undergone excision of a seborrhoiec wart on his left cheek this is removed by use of curretage leaving a superficial defect approximately 1cm in diameter. What is the best course of action?

Application of simple dressing 51%✅ Split thickness skin graft 5% Full thickness skin graft 5% Suturing of the wound with 2/0 nylon 22% Rotational local flap 17% This type of superficial wound will re-epithelialise satisfactorily without grafting.

A 23 year old man is undergoing an open appendicectomy. The surgeons extend the incision medially and suddenly encounter troublesome bleeding. What is the best course of action?

Apply topical haemostatic agents to the vessel 3% Ligate the bleeding vessel 70% ✅ Apply bipolar diathermy to the vessel 19% Use monopolar diathermy on blend setting to seal the vessel 8% Inject the area with dilute adrenaline 1% Medial extension of an appendicectomy incision carries the risk of injury to the inferior epigastric artery. This can bleed briskly and is best managed by ligation.

Which of the following substances is commonly used to sterilize endoscopic equipment?

Aqueous phenol 5% 80% phenol 7% Absolute alcohol 2% Glutaraldehyde 76%✅❤️ Gamma irradiation 10% Most endoscopic processors use glutaraldehyde which is an effective antimicrobial agent. It is widely recognized as being a cause of hypersensitivity reactions and is thus used in closed systems. Glutaraldehyde solution (2%) Colourless oily liquid, directly cytocidal and virucidal even at low temperatures Specifically used for endoscopes and some laparoscopic items, staff can rapidly develop allergy to this substance which has limited its more widespread use

A 43 year old lady is due to undergo a diagnostic laparoscopy. Which of the agents listed below should be used for inducing pneumoperitoneum?

Argon 1% Helium 2% Air 2% Carbon dioxide 90% Nitrogen 4% Carbon dioxide is the agent of choice. It is rapidly re-absorbed, does not support combustion and is cheap. It is rapidly cleared from the lungs and so effects on pH are unusual

A 12 month old child is brought to the clinic with a history of a right groin swelling. The parents have a photograph on their mobile phone which looks very much like an inguinal hernia. What is the best course of action?

Arrange an MRI scan 6% Undertake an open inguinal hernia repair with mesh 5% Undertake an open inguinal herniotomy 73%✅ Undertake a laparoscopic hernia repair with mesh 5% Arrange a herniogram 12% Where the history is strongly suggestive and the parents have a clear image or even description, most surgeons would proceed without confirmatory imaging. Herniograms and MRI would require a GA in a child of this age and are not routine. Herniotomy is the usual procedure and no mesh is used.

A 28 year old man presents with a recurrent inguinal hernia on the left side of his abdomen and a newly diagnosed inguinal hernia on the right side. What is the best course of action?

Bilateral open Litchenstein repair 14% Bilateral open inguinal herniotomy 2% Bilateral laparoscopic inguinal herniotomy 12% Bilateral laparoscopic TEP repair 70%✅ Bilateral open Shouldice repair 2% Laparoscopic hernia repairs are specifically indicated where there are bilateral hernias or recurrence of a previous open repair.

During an open Watsons Fundoplication, the inferior pole of the spleen is injured causing troublesome bleeding. What is the best course of action?

Bleeding from raw surfaces This may be mixed bleeding and can be troublesome. Spray diathermy and argon plasma coagulation are both useful agents. Certain topical haemostatic agents such as surgicell are useful in encouraging clot formation and may be used in conjunction with, or instead of, the above agents. Removal of the entire spleen 18% Partial splenectomy 15% Use of argon plasma coagulation system 42%✅ Sutured splenorrhaphy 16% Sutured ligation of the splenic hilar vessels 9% The argon plasma coagulation system is very good for managing splenic bleeding. Alternatives include topical haemostatic agents. Its not necessary to ligate the hilar vessels, if this is required, a splenectomy is the usual outcome.

Management of bleeding

Bleeding is a process that is encountered in all branches of surgery. The decision as to how best to manage bleeding depends upon the site, vessel and circumstances. Management of superficial dermal bleeding This will usually cease spontaneously. If it is troublesome then direct use of monopolar or bipolar cautery devices will usually control the situation. Scalp wounds are a notable exception and the bleeding from these may be brisk. In this situation the use of mattress sutures as a wound closure method will usually address the problem. Superficial arterial bleeding If the vessel can be safely identified then the easiest method is to apply a haemostatic clip and ligate the vessel. Major arterial bleeding If the vessel can be clearly identified and is accessible then it may be possible to apply a clip and ligate the vessel. If the vessel is located in a pool of blood then blind application of haemostatic clips is highly dangerous and may result in collateral injury. In this situation evacuating the clot and packing the area is often safer. The pack can then be carefully removed when the required instruments are available. Some vessels may retract and bleeding may then be controlled by dissection of surrounding structures or under-running the bleeding point. Major venous bleeding The safest initial course of action is to apply digital pressure to the bleeding point. To control the bleeding the surgeon will need a working suction device. Divided veins may require ligation. Incomplete lacerations of major veins (e.g. IVC) are best repaired. In order to do this it is safest to apply a Satinsky type vascular clamp and repair the defect with 5/0 prolene. Bleeding from raw surfaces This may be mixed bleeding and can be troublesome. Spray diathermy and argon plasma coagulation are both useful agents. Certain topical haemostatic agents such as surgicell are useful in encouraging clot formation and may be used in conjunction with, or instead of, the above agents.

In which electrosurgical modality is the active electrode placed in direct contact with the tissue and is characterised by low current and high voltage over a broad area?

Blended current 5% Cutting current 11% Coagulation current 37% Desiccation 34% ✅ Fulguration 14% In desiccation the device is placed in direct contact with the tissues (unlike fulguration). Because it is applied over a broad area it tends not to cause protein damage (unlike coagulation).

Polyglycolic acid (Vicryl, Dexon)

Braided Synthetic Up to 6 weeks Most tissues can be apposed using polyglycolic acid It has good handling properties, the dyed form of this suture should not be used for skin closure

Which of the following is not an absorbable suture material?

Chromic catgut 4% Nylon 79% Vicryl 5% Dexon 2% Poly diaxone (PDS).

During a pelvic lymphadenectomy, the common iliac vein is injured and there is profuse bleeding. What is the best course of action?

Clamp the vessel to gain a better view and then ligate it 13% Occlude the bleeding point with digital pressure and consider direct sutured repair with 5/0 polypropylene 71% Use diathermy at high coagulation current to stem the bleeding 1% Apply surgicell to the site and wait for bleeding to cease 2% Apply digital pressure to the vessel and suture the vessel with 2/0 polypropylene 13% The use of digital pressure and careful sutured repair is the preferred option.

During a pelvic lymphadenectomy, the common iliac vein is injured and there is profuse bleeding. What is the best course of action?

Clamp the vessel to gain a better view and then ligate it 13% Occlude the bleeding point with digital pressure and consider direct sutured repair with 5/0 polypropylene✅ 71% Use diathermy at high coagulation current to stem the bleeding 1% Apply surgicell to the site and wait for bleeding to cease 2% Apply digital pressure to the vessel and suture the vessel with 2/0 polypropylene 13% The use of digital pressure and careful sutured repair is the preferred option.

In which electrosurgical modality does a sinusoidal, non modulated waveform result in vaporization of the tissues?

Coagulation current 26% Cutting current 47%✅ Blended current 4% Fulguration 14% Desiccation 9% The high energy levels result in tissue vaporisation and cleavage of tissues. Cutting Sinusoidal and non modulated waveform High average power and current density Precise cutting without thermal damage

A surgeon wishes to determine whether different methods of perioperative shaving have an effect on post operative wound infection rates. Which of the following is the best method for assessing whether one method is better than the other?

Cohort study 15% Retrospective study 6% Case controlled study 20% Cross over study 1% Randomised controlled study 58%✅ A randomised controlled study is the best method for assessing this relationship. It is important to analyse data from RCT's on an intention to treat basis

A 73 year old lady presents with an ulcer overlying her medial malleolus. It is painless and has been present for 4 months. She has oedema of the lower limbs and her ABPI measures 0.9. What is the best management option?

Compression bandages 71%✅ Non compression bandaging 8% Split thickness skin grafting 5% Full thickness skin grafting 3% Angioplasty and non compression bandages 13% This is likely to be a venous leg ulcer. These are typically managed using compression bandages. Contra indications to this technique include peripheral vascular disease (not present here).

A 72 year old man undergoes a ray amputation of the foot for an infection complicating long standing diabetes. What is the best method for healing the resultant wound?

Compression bandaging 11% Vacuum assisted closure system 69%✅ Split thickness graft 4% Primary closure with 2/0 polypropylene 11% Full thickness skin graft 5% Ray amputations for diabetic foot infections do not heal well and should never be primarily closed. The use of vacuum assisted closure devices has been shown to improve healing rates.

A 43 year old man presents with dyspepsia and undergoes an upper GI endoscopy. During the procedure diffuse gastric and duodenal ulcers are identified. A Clo test confirms the presence of Helicobacter pylori infection. What is the most likely explanation for the ulcers?

Decreased gastric motility 1% Increased urease activity 41% Decreased release of mucous and bicarbonate 10% Decreased gastrin levels 2% Increased acid production 46%✅ H-Pylori has a number of pathological effects. In this question the main issue is by what mechanism the organism is able to induce both gastric and duodenal ulceration. Without modestly elevated acid levels, the duodenum would not undergo gastric metaplasia. H-Pylori cannot colonise duodenal mucosa and therefore the development of ulcers at this site can only occur in those who have undergone metaplastic transformation (mediated by increased acidity).

A 68 year old lady has a 3cm basal cell carcinoma excised from her right cheek. There is a rhomboid defect measuring 4cm by 4cm. What is the best option for managing the wound?

Delayed primary closure 2% Direct primary closure 6% Local rotational flap 69% Split thickness skin graft 12% Pedicled myocutaneous flap 12% A local rotational flap or full thickness graft would both be acceptable options here.

Descriptive statistics

Descriptive statistics include a point estimate of the measured variable as well as a measure of the variability of the data around that point estimate. Typical examples of point estimates include; mean, median and mode. The two most commonly employed measurements of variability include standard deviation and the inter quartile range. The standard deviation is usually considered in association with the mean, while the inter quartile range is used alongside the median. Other measures of data variability include the standard error of the mean and confidence interval. The standard error of the mean represents the measure of variation around the point estimate of the mean of a group of sample means, as such it should only be used when describing the characteristics of more than one sample.

In which electrosurgical mode is the electrode held away from the tissue, where the current utilises a low amplitude and high voltage?

Desiccation 13% Fulguration✅ 66% Blended current 3% Cutting current 6% Coagulation current 12% Fulguration typically avoids contact between the electrode and the tissue with the current configured to favor arc formation.

Surgical drains

Drains are inserted in many surgical procedures and are of many types. As a broad rule they can be divided into those using suction and those which do not. The diameter of the drain will depend upon the substance being drained, for example smaller lumen drain for pneumothoraces vs haemothorax. Drains can be associated with complications and these begin with insertion when there may be iatrogenic damage. When in situ they serve as a route for infections. In some specific situations they may cause other complications, for example suction drains left in contact with bowel for long periods may carry a risk of inducing fistulation. Drains should be inserted for a defined purpose and removed once the need has passed. A brief overview of types of drain and sites is given below CNS Low suction drain or free drainage systems may be used for situations such as drainage of sub dural haematomas. CVS Following cardiothoracic procedures of thoracic trauma underwater seal drains are often placed. These should be carefully secured. When an air leak is present they may be placed on suction whilst the air leak settles Orthopaedics and trauma In this setting drains are usually used to prevent haematoma formation (with associated risk of infection). Some orthopaedic drains may also be specially adapted to allow the drained blood to be auto transfused. Gastro-intestinal surgery Surgeons often place abdominal drains either to prevent or drain abscesses, or to turn an anticipated complication into one that can be easily controlled such as a bile leak following cholecystectomy. The type of drain used will depend upon the indication. Drain types Type of drain Features Redivac Suction type of drain Closed drainage system High pressure vacuum system Low pressure drainage systems Consist of small systems such as the lantern style drain that may be used for short term drainage of small wounds and cavities Larger systems are sometimes used following abdominal surgery, they have a lower pressure than the redivac system, which decreases the risks of fistulation May be emptied and re-pressurised Latex tube drains May be shaped (e.g. T Tube) or straight Usually used in non pressurised systems and act as sump drains Most often used when it is desirable to generate fibrosis along the drain track (e.g. following exploration of the CBD) Chest drains May be large or small diameter (depending on the indication) Connected to underwater seal system to ensure one way flow of air Corrugated drain Thin, wide sheet of plastic, usually soft Contains corrugations, along which fluids can track

Which of the following is least likely to reduce the risk of post operative wound infection?

Electrical clippers to remove body hair 15% Use of poviodone impregnated drapes 6% Antibiotic prophylaxis for prosthesis placement 7% Routine use of mechanical bowel preparation✅ 66% Chlorhexidine to prepare the skin 5% The routine use of mechanical bowel preparation is not recommended. There is some recent evidence to support the use of selective gut decontamination. However, this is not in mainstream practice at present.

Electrosurgery

Electrosurgery utilises the heat generated by the passage of high frequency alternating electrical current through living tissues. The application of a voltage across human tissue results in the formation of an electrical circuit between the voltage source and the tissue. The tissue acts as a resistor and the level of resistance is determined by the water content of the tissue. It is this resistance that results in the formation of heat. An alternating current constantly changes the direction in which the current flows, the speed with which this occurs is measured in Hertz. Most diathermy units operate at a frequency of between 200,000 kHZ to 5MHz. This means that tissue such as nerves and muscles will not depolarise (since this seldom occurs at frequencies above 10,000Hz). The current waveform can be adjusted to deliver three main therapeutic modalities; cutting, coagulation and blend. Types of current Cutting Sinusoidal and non modulated waveform High average power and current density Precise cutting without thermal damage Coagulation Modulated current with intermittent dampened sine waves of high peak voltage Evaporation, rather than vaporisation of intracellular fluid occurs Results in formation of coagulum Desication Active electrode in direct contact with tissue Low current and high voltage system Results in loss of cellular water but no protein damage Fulguration Electrode probe is held away from tissue Produces spray effect with local, superficial tissue destruction Low amplitude and high voltage system Blend Alternating cutting and coagulation modes Total average power is less than with cutting

A 73 year old man with rest pain and ulceration of the foot undergoes a femoro-distal bypass graft with a PTFE graft. At the end of the procedure there are good distal foot pulses and a warm pink foot. Over the ensuing 60 days the foot becomes progressively cooler and the pulses diminish. What is the most likely underlying explanation for this process?

Embolus 13% Neo-intimal flap 7% Neo-intimal hyperplasia 67%😍 Polyarteritis 2% Steal syndrome 10% Neo-intimal hyperplasia in distal arterial anastamoses may be reduced by use of a Miller Cuff when PTFE is the bypass conduit. PTFE may induce neo-intimal hyperplasia with subsequent occlusion of the distal anastomosis. In more proximal arterial bypass surgery the process of neo-intimal hyperplasia is not sufficient to cause anastomotic occlusion. However, distal bypasses are at greater risk and if vein cannot be used as a conduit then the distal end of the PTFE should anastomosed to a vein cuff to minimise the risk of neo-intimal hyperplasia.

A 34 year old man undergoes a sub total colectomy to treat fulminant ulcerative colitis. What type of stoma is most likely to be fashioned?

End colostomy 24% Loop colostomy 10% End ileostomy✅ 46% Loop ileostomy 19% End jejunostomy 1% A sub total colectomy involves the removal of the entire right, transverse, left and part of the sigmoid colon. The rectal stump is closed and an end ileostomy fashioned in the right iliac fossa. End ileostomy Usually following complete excision of colon or where ileo-colic anastomosis is not planned May be used to defunction colon, but reversal is more difficult Usually right iliac fossa

Which of these factors does not increase the risk of abdominal wound dehiscence following laparotomy?

Jaundice 5% Abdominal compartment syndrome 1% Poorly controlled diabetes mellitus 1% Administration of intravenous steroids 3% Use of Ketamine as an anaesthetic agent 90% Ketamine does not affect healing. All the other situations in the list carry a strong association with poor healing and risk of dehisence.

What type of stoma should be considered in a patient undergoing emergency operative intervention for large bowel obstruction as a result of a carcinoma 5cm from the anal verge?

End colostomy 32% Loop colostomy 37%✅ End ileostomy 8% Loop jejunostomy 1% Loop ileostomy 22% Don't confuse loop ileostomy and loop colostomy. A loop colostomy is the only safe option for an obstructing rectal cancer. Loop ileostomy in the context of rectal cancer is performed to mitigate the effects of anastomotic leak following a low anterior resection. Large bowel obstruction resulting from carcinoma should be resected, stented or defunctioned. The first two options typically apply to tumours above the peritoneal reflection. Lower tumours should be defunctioned with a loop colostomy and then formal staging undertaken prior to definitive surgery. An emergency attempted rectal resection carries a high risk of involvement of the circumferential resection margin and is not recommended. Loop colostomy To defunction a distal segment of colon Since both lumens are present the distal lumen acts as a vent May be located in any region of the abdomen, depending upon colonic segment used

A 72 year old man has discharge from a healed abdomino-perineal resection wound. On examination, it has almost completely healed but there is prominent granulation tissue at the apex of the wound. There is no evidence of an underlying collection and he is otherwise well. What is the best course of action?

Excision of the area 9% Cryotherapy 4% Application of topical silver nitrate 54%✅ Compression dressings 9% Application of alginate dressings 23% Silver nitrate will cauterise the exuberant granulation tissue and promote healing.

Flaps

Flaps have their own blood supply and may be pedicled or free. May have multiple components e.g. skin, skin + fat, skin + fat + muscle. They will have the ability to take regardless of the underlying tissue bed. The type of intrinsic blood supply is important. For example in breast surgery pedicled latissimus dorsi flaps will be less prone to failure than microsvascular anastomosed free Diep flaps.

In which of the following scenarios is a mucous fistula most likely to be encountered?

Following an elective right hemicolectomy and ileo-colic anastomosis 7% Following an Ivor Lewis oesophagectomy 6% Following an emergency sub total colectomy for severe colitis 61% Following an abdomino perineal excision of the colon and rectum for rectal cancer 19% Following a small bowel resection and primary anastomosis for incarcerated femoral hernia 7% A mucous fistula is a conduit between the skin and a redundant segment of bowel. They are typically constructed because the section of bowel that is exteriorized is at very high risk of breakdown. They are not the same as an end stoma, by definition they are usually seen in patients who have an end stoma. They are typically seen following a sub total colectomy where the distal sigmoid colon is deemed too friable to close and it then brought onto the skin as a mucous fistula.

Hartmann's Procedure

Hartmann's procedure is a type of colectomy that removes part of the colon and sometimes rectum (proctosigmoidectomy). The remaining rectum is sealed, creating what is known as Hartmann's pouch. The remaining colon is redirected to a colostomy. It can be reversed later.

One of the senior surgeons in the hospital advises as to the best management of Merkel cell tumours of the skin in which she has a special interest. What level of evidence is this?

I 8% II 4% III 3% IV 9% V✅ 76% Personal expert opinion qualifies for level V evidence.

A group of surgeons review a meta-analysis of a series of randomised controlled trials on the Cochrane database and decide that one type of hip replacement is superior to another. What level of evidence is this?

II 7% III 5% I✅😅 75% V 6% IV 6% A meta- analysis of more than one well designed trials will typically represent level I evidence. It does, of course, depend on how well the trials were conducted and reported.

An orthopaedic surgeon makes a modification to an operative approach for total knee arthroplasty. After he has completed 25 cases, he stops and reviews his patient outcomes. He publishes the data. What level of evidence is supplied by this type of data?

II 9% IV✅ 51% III 18% V 16% I 6% Case series that are non randomised and lack concurrent controls at best supply level IV evidence only. To qualify for level I and II evidence a prospective randomised controlled trial with appropriate blinding, control matching and power calculations is needed.

A group of surgeons are trying to decide which type of mesh to use for incisional hernia repair. Their assimilated evidence includes two case series and one randomised controlled trial. What level of evidence is this?

III 20% I 13% IV 15% II 49%✅ V 3% Data which includes at least one RCT will usually qualify for level II evidence.

A 52 year old man undergoes a laparotomy for perforated bowel after a colonoscopy. 2 days after surgery the nursing staff report there is pink, serous fluid discharging from the wound. What is the next most appropriate management step?

IV antibiotics for wound infection 10% No further management 14% Examine the wound for separation of the rectus fascia✅ 61% Insert a drain into the wound 3% CT abdomen 12% The seepage of pink serosanguineous fluid through a closed abdominal wound is an early sign of abdominal wound dehiscence with possible evisceration. If this occurs, you should remove one or two sutures in the skin and explore the wound manually, using a sterile glove. If there is separation of the rectus fascia, the patient should be taken to the operating room for primary closure

Which of the following methods is most effective at destroying spores of the tubercle bacilli?

Immersion in 0.5% chlorhexidine in alcohol 11% Immersion in aqueous iodine 2% Heating in a hot air oven 6% Immersion in 0.1% sodium hypochlorite 7% Autoclaving 73% The tubercle bacilli has a waxy outer membrane that renders it more resistant to sterilisation and cleaning methods. Whilst 0.1% sodium hypochlorite will destroy many microbes it is less reliable in destroying tubercle bacilli. Hot air ovens provide less reliable pathogen destruction than autoclaving, but may be indicated in situations where the equipment is sensitive to the autoclaving process. From the list of options above, autoclaving will most reliably destroy tubercle bacilli.

A 63 year old man with end stage osteoarthritis of the hip is due to undergo a total hip replacement. The skin has been prepared and antibiotics given. What is the single most important modality to reduce the risks of infection?

Laminar flow theatre✅ 59% Exhaust suits 2% Skin shaving on the ward 6% Total body scrubbing of the surgical team 10% Extended antibiotic chemoprophylaxis as routine 23% A laminar flow is the single most important intervention, many units will also use exhaust suits but these are less essential. Shaving skin on the ward increases infection rates. Extended chemoprophylaxis increases risks of antibiotic associated diarrhea.

Helicobacter Pylori

Infection with Helicobacter Pylori is implicated in many cases of duodenal ulceration and up to 60% of patients with gastric ulceration. It is a gram negative, helical shaped rod with microaerophillic requirements. It has the ability to produce a urease enzyme that will hydrolyse urea resulting in the production of ammonia. The effect of ammonia on antral G cells is to cause release of gastrin via a negative feedback loop. Once infection is established the organism releases enzymes that disrupt the gastric mucous layer. Certain subtypes release cytotoxins cag A and vac A gene products. The organism incites a classical chronic inflammatory process of the gastric epithelium. This accounts for the development of gastric ulcers. The mildly increased acidity may induce a process of duodenal gastric metaplasia. Whilst duodenal mucosa cannot be colonised by H-Pylori, mucosa that has undergone metaplastic change to the gastric epithelial type may be colonised by H- Pylori with subsequent inflammation and development of duodenitis and ulcers. In patients who are colonized, there is a 10-20% risk of peptic ulcer, 1-2% risk gastric cancer and <1% risk MALT lymphoma.

Inguinal hernia in children

Inguinal hernias in children are almost always of an indirect type and therefore are usually dealt with by herniotomy, rather than herniorraphy. Neonatal hernias especially in those children born prematurely are at highest risk of strangulation and should be repaired urgently. Other hernias may be repaired on an elective basis.

Inguinal hernia surgery

Inguinal hernias occur when the abdominal viscera protrude through the anterior abdominal wall into the inguinal canal. They may be classified as being either direct or indirect. The distinction between these two rests on their relation to Hesselbach's triangle. Boundaries of Hesselbach's Triangle Medial: Rectus abdominis Lateral: Inferior epigastric vessels Inferior: Inguinal ligament Image sourced from Wikipedia Hernias occurring within the triangle tend to be direct and those outside - indirect. Diagnosis Most cases are diagnosed clinically, a reducible swelling may be located at the level of the inguinal canal. Large hernia's may extend down into the male scrotum, these will not trans-illuminate and it is not possible to 'get above' the swelling. Cases that are unclear on examination, but suspected from the history, may be further investigated using ultrasound or by performing a herniogram. Treatment Hernias associated with few symptoms may be managed conservatively. Symptomatic hernias or those which are at risk of developing complications are usually treated surgically. First time hernias may be treated by performing an open inguinal hernia repair; the inguinal canal is opened, the hernia reduced and the defect repaired. A prosthetic mesh may be placed posterior to the cord structures to re-enforce the repair and reduce the risk of recurrence. Recurrent hernias and those which are bilateral are generally managed with a laparoscopic approach. This may be via an intra or extra peritoneal route. As in open surgery a mesh is deployed. However, it will typically lie posterior to the deep ring. Inguinal hernia in children Inguinal hernias in children are almost always of an indirect type and therefore are usually dealt with by herniotomy, rather than herniorraphy. Neonatal hernias especially in those children born prematurely are at highest risk of strangulation and should be repaired urgently. Other hernias may be repaired on an elective basis.

A 68 year old man undergoes a wide local excision of a squamous cell carcinoma from the lateral aspect of his nose. At the completion of the operation the alar cartilage is visible. What is the best method of closing the wound?

Interrupted 3/0 silk 1% Local rotational flap 76% Split thickness skin graft 5% Vacuum assisted closure system 1% Full thickness skin graft 17% This type of wound should be managed with a local rotational flap.

Which of the following statements relating to a burst abdomen is false?

Is seen in 1-2% of modern laparotomies 7% Is more common in faecal peritonitis 4% Is less common when a 'mass closure' technique is used 20% When it does occur is most common at 15 days✅ 48% Is similar in incidence regardless of whether 1/0 polydiaxone or 1/0 polypropylene are used 22% When it does occur, a burst abdomen is most common at 6 days and is usually the result of technical error when Jenkins rule is not followed and sutures are placed in the zone of collagenolysis. The choice of materials given above does not influence dehisence rates.

A 52 year old man with dyspepsia is found to have a duodenal ulcer. A CLO test is taken and is positive. Which statement relating to the likely causative organism is false?

It is a gram negative organism 14% It preferentially colonises gastric type mucosa 6% It may occupy areas of ectopic gastric metaplasia 16% In patients who are colonised there is commonly evidence of fundal gastritis on endoscopy 56% It produces a powerful urease that forms the basis of the Clo test 8% Helicobacter pylori accounts for >75% cases of duodenal ulceration. It may be diagnosed with either serology, microbiology, histology or CLO testing. Helicobacter pylori rarely produces any typical features on endoscopy. Where infection is suspected the easiest course of action is to take an antral biopsy for Clo testing in the endoscopy suite.

A 53 year old lady undergoes a low anterior resection for rectal cancer. The procedure is performed as open surgery, what is the most appropriate method for closure of the abdominal wall?

Mass closure of the abdomen obeying Jenkins rule using 1 PDS 71% ✅ Mass closure of the abdomen obeying Jenkins rule using 2/0 PDS 15% Mass closure of the abdomen obeying Jenkins rule using 1/0 nylon 11% Mass closure of the abdomen obeying Jenkins rule using 0 polygalactan 1% Use of deep tension sutures closure method using 5 polyester sutures 2% The standard closure technique for most laparotomy incisions is to use a mass closure method obeying Jenkins rule using 1 or 2 PDS or nylon. Few surgeons would use a narrower gauge suture such as 1/0 or 2/0 for abdominal wall closure.✅✅✅

A 73 year old man undergoes a laparotomy for mesenteric infarction. An extensive small bowel resection is undertaken. A planned re-look laparotomy is scheduled to occur in 24 hours time. What is the most appropriate closure strategy in this situation?

Mass closure of the abdomen obeying Jenkins rule using 2 PDS 11% Application of a Bogota bag 76% Mass closure of the abdomen obeying Jenkins rule using 2/0 PDS 7% Mass closure of the abdomen obeying Jenkins rule using 2 nylon 4% Mass closure of the abdomen obeying Jenkins rule using 2/0 nylon 3% Where there are definite plans for early re-look surgery and it is desirable to visualize the viscera (as it would be in this case), application of a Bogota bag will provide the best closure option.

A 73 year old man undergoes a laparotomy for mesenteric infarction. An extensive small bowel resection is undertaken. A planned re-look laparotomy is scheduled to occur in 24 hours time. What is the most appropriate closure strategy in this situation?

Mass closure of the abdomen obeying Jenkins rule using 2 PDS 11% Application of a Bogota bag 76%✅ Mass closure of the abdomen obeying Jenkins rule using 2/0 PDS 7% Mass closure of the abdomen obeying Jenkins rule using 2 nylon 4% Mass closure of the abdomen obeying Jenkins rule using 2/0 nylon 3% Where there are definite plans for early re-look surgery and it is desirable to visualize the viscera (as it would be in this case), application of a Bogota bag will provide the best closure option.

Which of the following is not utilised as a descriptive statistic?

Mean 2% Median 3% Mode 11% Z score✅ 75% Standard deviation 9% The z score is determined using the normal distribution and is not a descriptive statistic.

Boundaries of Hesselbach's Triangle

Medial: Rectus abdominis Lateral: Inferior epigastric vessels Inferior: Inguinal ligament

Methods of wound closure

Method of closure Indication Primary closure Clean wound, usually surgically created or following minor trauma Standard suturing methods will usually suffice Wound heals by primary intention Delayed primary closure Similar methods of actual closure to primary closure May be used in situations where primary closure is either not achievable or not advisable e.g. infection Vacuum assisted closure Uses negative pressure therapy to facilitate wound closure Sponge is inserted into wound cavity and then negative pressure applied Advantages include removal of exudate and versatility Disadvantages include cost and risk of fistulation if used incorrectly on sites such as bowel Split thickness skin grafts Superficial dermis removed with Watson knife or dermatome (commonly from thigh) Remaining epithelium regenerates from dermal appendages Coverage may be increased by meshing Full thickness skin grafts Whole dermal thickness is removed Sub dermal fat is then removed and graft placed over donor site Better cosmesis and flexibility at recipient site Donor site morbidity Flaps Viable tissue with a blood supply May be pedicled or free Pedicled flaps are more reliable, but limited in range Free flaps have greater range but carry greater risk of breakdown as they require vascular anastomosis

A 25 year old builder presents with a reducible swelling in the right groin, it is becoming larger and has not been operated on previously. What is the best course of action?

Open inguinal herniotomy 11% Laparoscopic inguinal herniotomy 14% Open Bassini repair 5% Laparoscopic Bassini repair 13% Open Lichtenstein repair 57%✅ The hernia can be repaired by either open or laparoscopic techniques. However, herniotomy is not performed as an isolated procedure in adults. The Bassini darn repair has a high recurrence rate. An open Lichtenstein repair using mesh is appropriate. There is a 0.77% recurrence rate with this technique. A Shouldice repair is an acceptable alternative if the surgeon is experienced

A 28 year old man is undergoing an appendicectomy for perforated appendicitis. What is the single most important modality for reducing the risks of post operative wound infection?

Peri- operative administration of antibiotics✅ 81% Use of suction drains in the abdominal wall 6% Use of passive drains in the abdomen 6% Use of skin clips for closure 1% Use of incise drapes 6% Antibiotics are the single most important factor. Clips make infections easier to manage but do not reduce the risks. Drains have no effect on the skin wounds in these cases.

A 28 year old man undergoes an incision and drainage of an axillary abscess. How should the wound be managed?

Primary closure 2% Delayed primary closure 19% Packing with alginate dressing✅ 47% Packing with gauze 31% Skin grafts 0% Use of gauze is inappropriate and will be painful to redress. Abscess wounds should not be closed

A 63 year old male is gardening when he trips and lands on a scythe. He sustains a deep laceration of his lateral thigh, it measures 3cm depth by 7cm length, it penetrates down to the bone, but no fracture is evident on imaging or examination. His co- morbidities include type II diabetes mellitus (diet controlled) and polymyalgia rheumatica (takes regular low dose prednisolone). Which of the options below is the safest way of managing the wound?

Primary closure using deep tension sutures 11% Primary closure in layers 29% Delayed primary closure 53%✅ Full thickness skin graft 4% Split thickness skin graft 3% Wounds which are contaminated or have the potential to become so are unsafe for immediate primary closure. The combination of diabetes and steroids makes wound complications more likely. Despite his high risk a primary skin graft or flap is unlikely to be a safer option. Either may be used at a later date in the event that delayed primary closure is unsuccessful.

Randomised controlled trials

Randomised controlled trials are an established method of comparing two variables. These may consist of comparison of treatments or treatment versus placebo. Ideally the trials should be blinded, usually to the patient and those treating them. In most cases a power calculation should be performed to determine the sample size required to detect a difference.

Options of managing open or dehicenced wound

Resuturing of the wound This may be an option if the wound edges are healthy and there is enough tissue for sufficient coverage. Deep tension sutures are traditionally used for this purpose. Application of a wound manager This is a clear dressing with removable front. Particularly suitable when some granulation tissue is present over the viscera or where there is a high output bowel fistula present in the dehisced wound. Application of a 'Bogota bag' This is a clear plastic bag that is cut and sutured to the wound edges and is only a temporary measure to be adopted when the wound cannot be closed and will necessitate a return to theatre for definitive management. Application of a VAC dressing system These can be safely used BUT ONLY if the correct layer is interposed between the suction device and the bowel. Failure to adhere to this absolute rule will almost invariably result in the development of multiple bowel fistulae and create an extremely difficult management problem.

A 5 year old suffers 20% burns to the torso. On examination, there is fixed pigmentation and the affected area has a white and dry appearance. Which of the following options represents the best management plan?

Rotational myocutaneous flap 6% Full thickness skin graft 19% Excision and delayed primary closure 5% Debridement and split thickness skin graft✅ 68% Excision and direct primary closure 1% This is a full thickness burn and will require split thickness skin grafting. Meshing the graft may increase the donor site yield. However, this is at the expense of cosmesis. The burn itself must be debrided first to ensure an adequate wound bed.

Tissue reconstruction

Skin Grafts and Flaps Skin flaps or grafts may be required where primary wound closure cannot be achieved or would entail either significant cosmetic defect or considerable functional disturbance as a result of wound contraction. Reconstructive ladder Method Types Direct closure The simplest option where possible Grafting techniques Split thickness Full thickness Skin Substitute Composite Flap technique Local: Transposition Pivot Alphabetoplasty (e.g. Z-Y) Regional: Myocutaneous Fasciocutaneous Neurocutaneous Distant: Free tissue transfer Prelamination techniques Allows creation of specialised flaps e.g. buccal mucosa Tissue expansion Involves placement of tissue expanders to increase amount of tissue at donor sites Skin Grafts Vs. Flaps Skin Grafts Flaps No size limit (Split)/ Relative size limit (full thickness) Size limited by territory of blood supply Rely on wound bed for blood supply Tissue has its own blood supply Take better on clean well vascularised wound beds Will survive independent of the wound bed Split skin graft donor site typically heals in 12 days Direct closure of donor site or secondary skin graft Donor site may be reused Donor site cannot be reused Split thickness skin grafts Available in range of thicknesses. Thigh is the commonest donor site Size may be increased by meshing the graft. However this comes with compromise on cosmesis. Donor sites, especially if thin grafts are taken can be reused following re-epithelialisation Full thickness grafts Most commonly used for facial reconstruction Include dermal appendages Provide superior cosmetic result Composite grafts These are grafts containing more than one tissue type, such as skin and fat. They are usually used to cover small defects in cosmetically important areas. Flaps Flaps have their own blood supply and may be pedicled or free. May have multiple components e.g. skin, skin + fat, skin + fat + muscle. They will have the ability to take regardless of the underlying tissue bed. The type of intrinsic blood supply is important. For example in breast surgery pedicled latissimus dorsi flaps will be less prone to failure than microsvascular anastomosed free Diep flaps.

A 32 year old man is involved in a road traffic accident and sustains a significant laceration to the lateral aspect of the nose which is associated with tissue loss. What is the best management option?

Split thickness skin graft 14% Rotational skin flap 75% Delayed primary closure 6% Simple primary closure 4% Use of vacuum closure system 1% Nasal injuries can be challenging to manage and where there is tissue loss, it can be difficult to primarily close them and still obtain a satisfactory aesthetic result. Debridement together with a rotational flap would obtain the best results here.

Which of the following visceral anastomoses has the lowest risk of anastomotic leak? You may assume that all are constructed in ideal circumstances.

Stapled ileocolic anastomosis 8% Hand sewn anastomosis of the proximal ileum 55% Stapled colorectal anastomosis defunctioned with loop ileostomy 19% Stapled colorectal anastomosis defunctioned with loop colostomy 10% Hand sewn oesophagojejunal anastomosis 8% For a visceral anastomosis to heal, three factors need to be satisfied: 1. Mucosal- mucosal apposition 2. A good blood supply 3. No tension The more these are compromised, the higher the leak rate. Rectal and oesophageal surgery have some of the highest rates of anastomotic leakage. Following anterior resection leaks are quoted to occur in up to 10% of cases. Small bowel anastomoses are the most technically forgiving. Factors increasing the risk of anastamotic leakage include previous irradiation, sepsis, malnutrition, poor blood supply and poor technique. The defunctioning of rectal anastomoses may reduce the clinical impact of anastomotic leak and make it amenable to percutaneous drainage, but does not necessarily reduce the incidence of leaks themselves

Abdominal stomas

Stomas may be sited during a range of abdominal procedures and involve bringing the lumen or visceral contents onto the skin. In most cases this applies to the bowel. However, other organs or their contents may be diverted in case of need. With bowel stomas the type method of construction and to a lesser extent the site will be determined by the contents of the bowel. In practice, small bowel stomas should be spouted so that their irritant contents are not in contact with the skin. Colonic stomas do not need to be spouted as their contents are less irritant. In the ideal situation the site of the stoma should be marked with the patient prior to surgery. Stoma siting is important as it will ultimately influence the ability of the patient to manage their stoma and also reduce the risk of leakage. Leakage of stoma contents and subsequent maceration of the surrounding skin can rapidly progress into a spiraling loss of control of stoma contents. Types of stomas Name of stoma Use Common sites Gastrostomy Gastric decompression or fixation Feeding Epigastrium Loop jejunostomy Seldom used as very high output May be used following emergency laparotomy with planned early closure Any location according to need Percutaneous jejunostomy Usually performed for feeding purposes and site in the proximal bowel Usually left upper quadrant Loop ileostomy Defunctioning of colon e.g. following rectal cancer surgery Does not decompress colon (if ileocaecal valve competent) Usually right iliac fossa End ileostomy Usually following complete excision of colon or where ileo-colic anastomosis is not planned May be used to defunction colon, but reversal is more difficult Usually right iliac fossa End colostomy Where a colon is diverted or resected and anastomosis is not primarily achievable or desirable Either left or right iliac fossa Loop colostomy To defunction a distal segment of colon Since both lumens are present the distal lumen acts as a vent May be located in any region of the abdomen, depending upon colonic segment used Caecostomy Stoma of last resort where loop colostomy is not possible Right iliac fossa Mucous fistula To decompress a distal segment of bowel following colonic division or resection Where closure of a distal resection margin is not safe or achievable May be located in any region of the abdomen according to clinical need

Arterial bleeding

Superficial arterial bleeding If the vessel can be safely identified then the easiest method is to apply a haemostatic clip and ligate the vessel. Major arterial bleeding If the vessel can be clearly identified and is accessible then it may be possible to apply a clip and ligate the vessel. If the vessel is located in a pool of blood then blind application of haemostatic clips is highly dangerous and may result in collateral injury. In this situation evacuating the clot and packing the area is often safer. The pack can then be carefully removed when the required instruments are available. Some vessels may retract and bleeding may then be controlled by dissection of surrounding structures or under-running the bleeding point.

Sterilisation

Surgical equipment has to be cleaned and sterilised prior to use. The extent to which these processes will be required varies according to the type of equipment and the purpose for which it will be used. In general, the three processes are relevant; cleaning, disinfection and sterilisation. Cleaning refers to removal of physical debris. Disinfection refers to reduction in numbers of viable organisms. Sterilisation is removal of all organisms and spores. Methods Method Details Indication Autoclaving Air removed and high pressure steam used (usually 134 oC for 3 minutes) Most reusable surgical equipment, must be physically cleaned prior to autoclaving, unsuitable for fragile items Glutaraldehyde solution (2%) Colourless oily liquid, directly cytocidal and virucidal even at low temperatures Specifically used for endoscopes and some laparoscopic items, staff can rapidly develop allergy to this substance which has limited its more widespread use Ethylene oxide 3% mixture of gas with carbon dioxide used Used for packaged materials that cannot be heated, the gas is explosive and environmentally toxic, it is used mainly in the industrial setting Gamma irradiation Gamma rays emitted from radioactive substance such as cobalt 60 or caesium 137 Suitable for batch treatment of relatively thermostable items, typically an industrial process

Suture material

Suture materials Agent Classification Durability Uses Special points Silk Braided Biological Theoretically permanent although strength not preserved Anchoring devices, skin closure Knots easily, poor cosmesis Catgut Braided Biological 5-7 days Short term wound approximation Poor cosmesis Degrades rapidly Not available in UK Chromic catgut Braided Biological Up to 12 weeks Apposition of deeply sited tissues Unpredictable degradation pattern Not in use in UK Polydiaxanone (PDS) Synthetic Monofilament Up to 3 months (longer with thicker sutures) Widespread surgical applications including visceral anastomoses, dermal closure, mass closure of abdominal wall Used in most surgical specialties (avoid dyed form in dermal closure) Polyglycolic acid (Vicryl, Dexon) Braided Synthetic Up to 6 weeks Most tissues can be apposed using polyglycolic acid It has good handling properties, the dyed form of this suture should not be used for skin closure Polypropylene (Prolene) Synthetic Monofilament Permanent Widely used, agent of choice for vascular anastomoses Poor handling properties Polyester (Ethibond) Synthetic Braided Permanent Its combination of permanency and braiding makes it useful for laparoscopic surgery It is more expensive and has considerable tissue drag Absorbable vs Non absorbable Time taken to degrade absorbable materials varies Usually by macrophages hydrolysing material Consider absorbable sutures in situations where long term tissue apposition is not required. In cardiac and vascular surgery non absorbable sutures are usually used. Suture size The higher the index number the smaller the suture i.e. : 6/0 prolene is finer than 1/0 prolene. Finer sutures have less tensile strength. For example 6/0 prolene would not be a suture suitable for abdominal mass closure but would be ideal for small calibre distal arterial anastomoses. Braided vs monofilament Generally speaking braided sutures have better handling characteristics than non braided. However, they are associated with higher bacterial counts. Braided materials are unsuitable for use in vascular surgery as they are potentially thrombogenic.

A 28 year old man presents with a direct inguinal hernia. A decision is made to perform an open inguinal hernia repair. Which of the following is the best option for abdominal wall reconstruction in this case?

Suture plication of the transversalis fascia using PDS only 2% Suture plication of the hernial defect with nylon and placement of prolene mesh anterior to external oblique 13% Suture plication of the hernia defect using nylon and re-enforcing with a sutured repair of the abdominal wall 5% Sutured repair of the hernial defect with prolene and placement of prolene mesh over the cord structures in the inguinal canal 21% Sutured repair of the hernial defect using nylon and placement of a prolene mesh posterior to the cord structures 59% Laparoscopic repair- bilateral and recurrent cases During an inguinal hernia repair in males the cord structures will always lie anterior to the mesh. In the conventional open repairs the cord structures are mobilised and the mesh placed behind them, with a slit made to allow passage of the cord structures through the deep inguinal ring. Placement of the mesh over the cord structures results in chronic pain and usually a higher risk of recurrence. Laparoscopic inguinal hernia repair is the procedure of choice for bilateral inguinal hernias. Types of surgery include: Onlay mesh repair (Lichtenstein style) Inguinal herniorrhaphy Shouldice repair Darn repair Laparoscopic mesh repair Open mesh repair and laparoscopic repair are the two main procedures in mainstream use. The Shouldice repair is a useful procedure in cases where a mesh repair would be associated with increased risk of infection, e.g. repair of case with strangulated bowel, as it avoids the use of mesh. It is, however, far more technically challenging to perform

Polypropylene (Prolene)

Synthetic Monofilament Permanent Widely used, agent of choice for vascular anastomoses Poor handling properties

Polydiaxanone (PDS)

Synthetic Monofilament Up to 3 months (longer with thicker sutures) Widespread surgical applications including visceral anastomoses, dermal closure, mass closure of abdominal wall Used in most surgical specialties (avoid dyed form in dermal closure)

A 75 year old man undergoes a Hartman's procedure for sigmoid diverticular disease with pericolic abscess and colovesical fistula. What type of drain should be inserted following this procedure?

T Tube drain 6% Wallace Robinson drain (non suction) 55%✅ Redivac drain 24% Corrugated drain 12% No drain 3% A non suction drain is the preferred option here. Low pressure drainage systems Consist of small systems such as the lantern style drain that may be used for short term drainage of small wounds and cavities Larger systems are sometimes used following abdominal surgery, they have a lower pressure than the redivac system, which decreases the risks of fistulation May be emptied and re-pressurised

A 63 year old man undergoes a salvage abdominoperineal excision of the anus and rectum for recurrent anal cancer. He has previously been treated with radical chemoradiotherapy. At the conclusion of the procedure, there is a 10cm x 10cm perineal skin defect. What is the most appropriate option for providing closure?

Use of a VAC wound management system 21% Rotational skin flap 16% Deep tension sutures and primary closure 5% Pedicled myocutaneous flap 48%✅ Delayed primary closure 9% The use of previous radiotherapy means that the wound will not heal well. A myocutaneous flap will mean that non irradiated tissue is interposed into the wound bed. Rotational skin flaps will comprise irradiated tissue and won't heal.

A 59 year old lady undergoes a breast reconstruction following a mastectomy. A breast implant is placed anterior to pectoralis major. What is the most appropriate method of wound closure?

Use of a full thickness skin graft 6% Use of a split thickness skin graft 3% Use of a pedicled myocutaneous flap 76% Use of a free myocutaneous flap 12% Use of a microvascular free flap 3% The use of a pedicled latissimus dorsi flap is a common method of providing breast reconstruction over an implant. Free flaps do not heal as reliably as pedicled ones and these would therefore be used in preference in this particular setting.

You have just completed a laparotomy for peritonitis due to a perforated peptic ulcer. What is the best surgical strategy for avoidance of a complete abdominal wound dehisence?

Use of skin clips to close the skin rather than sub cuticular sutures 6% Careful approximation of the peritonum with non absorbable sutures 9% Mass closure of the midline wound using a 1 polydiaxone suture 68%✅ Direct apposition of the rectus muscle rather than linea alba aponeurosis 7% Mass closure of the midline wound using a 3/0 polypropylene suture 10% The incidence of post operative wound dehisence is minimise by following Jenkins rule which advocates mass closure of the midline wound. However, the suture strength is an important consideration and 3/0 sutures do not have sufficient tensile strength. Both polydiaxone (PDS) and polypropylene (Prolene) or nylon (Ethilon) are all equally suitable. Although separate closure of the peritoneum was practised it has no bearing on the incidence of abdominal wound dehisence.

Vacuum assisted closure

Uses negative pressure therapy to facilitate wound closure Sponge is inserted into wound cavity and then negative pressure applied Advantages include removal of exudate and versatility Disadvantages include cost and risk of fistulation if used incorrectly on sites such as bowel

Mass closure

is continuous fascial closure with a single suture. This method allows even distribution of tension across the entire length of the suture, resulting in minimization of tissue strangulation. The goal is approximation of tissue edges to allow scar formation.

Jinkins rule

The formula is that, for a continuous suture, the length of suture used should be at least four times the length of the wound (T.P.N. Jenkins' rule), with sutures 1 cm apart and with 1 cm bites of the wound edge

Levels of evidence

The level of evidence refers to the study design used by investigators to minimise bias. Level of evidence Source I Evidence obtained from systematic review of all relevant randomised controlled trials II Evidence derived from at least one properly designed randomised controlled trial III Evidence derived from well designed pseudo-randomised controlled trials (e.g. alternate allocation) or historical controls IV Evidence derived from case series or case reports V Panel or expert opinion Many of the categories contain sub groups, detailed knowledge of these are not required for MRCS Part A.

Composite grafts

These are grafts containing more than one tissue type, such as skin and fat. They are usually used to cover small defects in cosmetically important areas.

Abdominal wound dehiscence

This is a significant problem facing all surgeons who undertake abdominal surgery on a regular basis. Traditionally, it is said to occur when all layers of an abdominal mass closure fail and the viscera protrude externally (associated with 30% mortality). It can be subdivided into superficial, in which the skin wound alone fails and complete, implying failure of all layers. Factors which increase the risk are: * Malnutrition * Vitamin deficiencies * Jaundice * Steroid use * Major wound contamination (e.g. faecal peritonitis) * Poor surgical technique (Mass closure technique is the preferred method-Jenkins Rule) When sudden full dehiscence occurs the management is as follows: * Analgesia * Intravenous fluids * Intravenous broad spectrum antibiotics * Coverage of the wound with saline impregnated gauze (on the ward) * Arrangements made for a return to theatre Surgical strategy Correct the underlying cause (e.g. TPN or NG feed if malnourished) Determine the most appropriate strategy for managing the wound Options Resuturing of the wound This may be an option if the wound edges are healthy and there is enough tissue for sufficient coverage. Deep tension sutures are traditionally used for this purpose. Application of a wound manager This is a clear dressing with removable front. Particularly suitable when some granulation tissue is present over the viscera or where there is a high output bowel fistula present in the dehisced wound. Application of a 'Bogota bag' This is a clear plastic bag that is cut and sutured to the wound edges and is only a temporary measure to be adopted when the wound cannot be closed and will necessitate a return to theatre for definitive management. Application of a VAC dressing system These can be safely used BUT ONLY if the correct layer is interposed between the suction device and the bowel. Failure to adhere to this absolute rule will almost invariably result in the development of multiple bowel fistulae and create an extremely difficult management problem.

Laminar flow theater

This is described as an entire body of air within a designated space (theatre suite) moving with uniform velocity in a single direction along parallel flow lines.

Suture sizes

USP Suture size and corresponding suture diameter USP Size Diameter in mm 11-0 0.01 10-0 0.02 6-0 0.07 3-0 0.2 0 0.35 1 0.4