Anatomy and Physiology: Case Studies

Barbara survived transport to the hospital and notes recorded at admission included the following observations:

- right thorax compressed; ribs 7 to 9 fractured - right lung atelectasis

1. In organ transplants, the transplanted organ is referred to as a graft. What type of graft is represented by the two kidneys that Mr. Ayers has donated?

Allografts.

1.Urine glucose is usually negative. Using the information in Appendix F, identify whether each test result is normal or abnormal.

Blood pH: Low (normal: 7.35-7.45); blood glucose: high (normal: 70-120); blood ketone bodies: high (normally -ve); urine pH: low (normal: 4.5-8)

Chaper 22 Barbara Joley was in the bus that was hit. When she was freed from the wreckage, she was deeply cyanotic and her respiration had stopped. Her heart was still beating, but her pulse was fast and thready.

The emergency medical technician reported that when Barbara was found, her head was cocked at a peculiar angle and it looked like she had a fracture at the level of the C2 vertebra.

2. Mr. Malone was switched from saline to PRBCs. What problem does infusion of PRBCs address that the saline solution could not?

The PRBCs contain oxygen-carrying hemoglobin. While the saline replaces lost blood volume, it cannot replace the hemoglobin in the lost RBCs. (In acute trauma, the rule of thumb is to use no more that 2L of normal saline before starting PRBCs, so that the hematocrit does not drop below 30%).

3. The doctors noted that there were no bone fragments in the joint space. What is normally found in this space?

The joint space in a synovial joint is normally filled with synovial fluid.

4. c) Gastrocnemius

This muscle is a powerful plantar flexor. The therapist can 1) ask Mrs. Tanner to raise her body up on her toes using her right foor, or 2) apply pressure to the bottom of the foot and ask Mrs. Tanner to push against that resistance.

3. Mrs. Rodriguez's doctors explained that the blood loss she suffered as a result of the accident occurred approximately 10-12 days after her most recent ovulation. Explain why this may help ease her fears about harm to her baby?

While any amount of trauma can be cause for concern with a pregnancy, her accident occurred prior to the formation of the placenta. If her accident had occurred a few weeks later, her blood loss may have had an impact on the oxygenation of her developing fetus.

3.Why is Barbara cyanotic? Explain cyanosis.

Cyanosis is a decrease in the degree of oxygen saturation of hemoglobin. As her respiratory efforts cease, her alveolar Po2 will fall, so there is less oxygen to load onto hemoglobin. In her peripheral tissues, what little oxygen hemoglobin carries will be consumed, leaving these tissues with a bluish tinge.

4. Mrs. DeStephano's cyanotic skin may hint at what additional problem (and impairement of what body systems or functions)?

Cyanosis signals a decrease in the amount of oxygen carried by hemoglobin in the blood. Respiratory system and/or cardiovascular system impairements can lead to cyanosis.

2. Describe the type of inheritance that is represented by blood type.

Blood type is determined by multiple-allele inheritance. Three alleles (IA, IB, I) represent the three different blood types (A, B, O). The alleles for A and B blood type are codominant, which means that they are both expressed when combined together. The result of this combination would be the AB blood type. The allele for O blood type is recessive to both the A and B blood type alleles.

6. What new techniques might be used to enhance fracture repair if healing is delayed or impaired?

For a fracture that is slow to heal, new techniques that promote healing include electrical stimulation, which promotes the deposition of new bone tissue; ultrasound treatments, known to speed healing; and possibly the addition of bone substitutes to the fractured area.

4. Mrs. Tanner suffered an injury to the hip joint, but if you were asked to rest your hands on your hips, you would not actually touch this joint. What structure in the pelvic girdle would your hands be resting on?

If you were asked to rest your hands on your hips, our hands would be resting on the iliac crests.

2. A "fruity acetone combined with alcohol" smell was detected in his breath, and in his urine. Which substance is producing this smell?

Ketone bodies have an acetone smell that can be detected in the urine and the breath . He is producing abnormal amounts of ketone bodies, which are accumulating in his blood. These substances are being excreted into the urine and diffusing out of the lungs and into the exhaled air.

4. Explain the reasoning behind the dietary recommendations.

Mrs. DeStephano's physician wants to supply her damaged tissues with the necessary building materials to encourage healing. A high-protein diet will provide plenty of amino acids to rebuild or replace damaged proteins, carbs will provide the fuel molecules needed to generate the required ATP, and vitamin C is important for the regeneration of connective tissue.

3. What benefit is conferred by suturing the lacerations?

Suturing brings the edges of wounds close together and promotes faster healing because smaller amounts of granulation tissue need to be formed. This is termed healing by first intention.

7. What treatment will be done to reverse the atelectasis? What is the rationale for this treatment.

The atelectasis will be reversed by inserting a chest tube and removing the air form the pleural cavity. This will allow her lung to heal and reinflate.

1. The adult brain can be broken down into four functional regions. Based on the observed signs in this case, which of these four brain regions is involved? What evidence did you use to determine this?

The four regions of the brain are the cerebral hemispheres, diencephalon, brain stem, and cerebellum. A cerebral hemisphere is involved in this case. Motor functions and language are both located in this cerebral hemisphere and have been affected by the injury.

1. Mrs. Tanner's pelvic girdle contains a hemispherical socket at the point where her femur attaches. Name this structure.

The hemispherical socket at the point where her femur attaches is called the acetabulum.

1. Joints can be classified by structure and by function. How would you structurally and functionally classify the joint involved in the injury in this case?

The hip joint would be structurally classified as a synovial joint and functionally classified as a diarthrotic (freely movable) joint.

Chapter 9 Mrs. DeStephano: skeletal musculature. - severe lacerations of the muscles of the right leg and knee - damage to the blood vessels serving the right leg and knee - transection of the sciatic nerve (the large nerve serving most of the lower limb), just above the right knee

Her physician orders daily passive range-of-motion (ROM) exercise and electrical stimulation for her right leg and a diet high in protein, carbohydrates, and vitamin C.

3. c) With Mrs. Tanner in the prone position (on her stomach), the therapist applied resistance to the leg while Mrs. Tanner was instructed to bring her heel up toward her buttocks (flex her knee).

This addresses the function of the muscles of the posterior compartment of the thigh. The hamstrings are the prime movers involved in knee flexion.

2. What complications in healing can be anticipated owing to vascular (blood vessel) damage in the right leg?

Healing is aided by good circulation of blood within the inured area. Vascular damage compromises healing because the supply of oxygen and nutrients to the tissue is reduced.

At his two-week appointment at the outpatient clinic, Mr. Boulard complains of fatigue, weakness, muscle cramps, and irregular heartbeats. A physical examination and lab tests produce the following observations:

- BP 133/90, HR 75 - Blood K+ 2.9 mEq/L (normal 3.5-5); blood Na+ 135 (normal 135-145) - urine K+ 55 (normal , 40); urine Na+ 21 (normal >20)

Chapter 6 Remember Mrs. DeStephano? When we last heard about her she was being admitted for further studies. Relative to her skeletal system, the following notes have been added to her chart.

- Fracture of superior right tibia (shinbone of leg); skin lacerated; area cleaned and protruding bone fragments subjected to internal (open) reduction and casted - nutrient artery of tibia damaged - medial meniscus (fibrocartilage disc) of right knee joint crushed; knee joint inflamed and painful

Chapter 23 Mr. Gutteman: Complains of a headache, gnawing epigastric pain, and "the runs". To pinpoint the problem, he is asked the following questions.

- Have you had these symptoms previously? (Yes, but never this bad.) - Are you allergic to any foods? (Shellfish doesn't like me and milk gives me the runs.) As a result of his responses, a lactose-free diet is ordered for Mr. Gutteman instead of the regular diet originally prescribed.

4. Why is the matching of the MHC molecules and the tissue compatibility so important in this case?

A foreign MHC protein will provoke an immune response, so the donor's and recipient's MHCs must match as closely as possible to minimize such an attack. tissue typing dramatically reduces the risk of organ rejection due to attack by the recipient's immune system.

Chapter 12 Margaret Bryans, a 39-year-old female, was a passenger on the bus hat crashed on Route 91. When paramedics arrived on the scene, she was unconscious, with cuts on her arms, face, and scalp. She regained consciousness en route to the hospital and appeared agitated and combative. Paramedics observed that she had a right hemiparesis (muscle weakness), with a near complete paresis of her right upper extremity and a partial paresis of the right lower extremity.

A head CT scan revealed an acute subdural hematoma and an extensive subarachnoid hemorrhage. Doctors noted that she was able to follow commands from medical personnel. With difficulty, she could speak haltingly, using only simple words. Surgery to remove large clots from the subarachnoid space was performed immediately. Two weeks after the surgery, she showed significant improvement in her speech and motor function.

1. What hormone did the hospital detect in her blood to determine that she was pregnant?

A hospital pregnancy test works by detecting human chorionic gonadotropin (hCG) in the blood. Home pregnancy test kits detect this hormone in the urine.

1. Describe the difference between genotype and phenotype. What are the phenotypes and genotypes of Mr. and Mrs. Rodriguez?

A person's genotype is a description of the alleles that they carry. Phenotype refers to the way that those genes are expressed and show up as traits in the body. Mrs. Rodriguez's genotype is ii and her phenotype is O. Mr. Rodriguez's genotype is either IAIA or IAi. Either one of these genotypes would result in his phenotype, which is represented by his A blood type.

1. During her initial visit with the physical therapist, Mrs. Tanner presented with significant "foot drop" (the inability to dorsiflex the foot when taking a step). Mrs. Tanner was asked to perform a variety of movements with her right lower extremity. The therapist focused her attention on the prime movers and synergists of the hip, knee, and ankle. What are "prime movers" and "synergists"?

A prime mover is a muscle that has primary or major responsibility for producing a specific movement. A synergist is a muscle that supports or helps the action of a prime mover by adding extra force, or providing stability so that the prime mover can perform its action.

Chapter 27 Mr. Heyden: Has had an X ray to determine the cause of his back pain, and his blood test results have come in.

According to the note recorded at radiology: X irradiation of skeleton displays numerous carcinomatous metastases in his skull and lumbar vertebrae. The hematology note of interest here reads: PSA levels abnormally high.

1. What is albumin? Is it normally found in the urine? If not, what does its presence suggest?

Albumin is the smallest and most abundant plasma protein. More than trace amounts of albumin are not normal found in urine, so its presence indicates damage to the filtration membrane of the nephron.

2. In order to assess the function and strength of a specific muscle, a physical therapist will often apply resistance (push against the moving limb) to mimic the action of an antagonist muscle. What is an antagonist muscle, and why would the therapist mimic its action?

An antagonist is a muscle that opposes, resists, or reverses a particular movement. By mimicking the action of an antagonist, the therapies can test the strength of the agonist muscle and compare it with the same muscle in the other limb.

1. Explain the rationale behind these orders.

As he is unconscious, the level of damage to his brain is unclear. Monitoring his responses and vital signs every hour will provide information for his care providers about the extent of his injuries. Turning him every 4 hours and providing careful skin care will prevent decubitus ulcers (bedsores) as well as stimulating his proprioceptive pathways.

7. How likely is it that Mrs. DeStephano's knee cartilage will regenerate? Why?

At age 45, Mrs. DeStephanos will most likely not regenerate her knee cartilage. (Cartilage growth typically ends during adolescence.) Cartilage damage that occurs during adulthood is slow to heal, due to the avascular nature of cartilage, and is usually irreparable. Surgical removal of cartilage fragments to allow improved movement of the joint is the usual treatment for this type of damage.

5. What is atelectasis and why is only the right lung affected?

Atelectasis is the collapse of a lung. Because it is the right thorax that is compressed, only her right lung is affected. Because the lungs are in separate pleural cavities, only the right lung collapsed.

6. How do ACE inhibitors reduce blood pressure?

By blocking the action of angiotensin converting enzymes and so reducing the amount of circulating angiotensin II. Because angiotensin II increases BP in a number of ways, including by increasing aldosterone release and causing vasoconstriction, ACE inhibitors are very effective at lowering blood pressure.

1. What is carcinoma? What do you suppose is the primary source of the secondary carcinoma lesions in his skull and spine?

Carcinoma is the term for cancer originating from epithelial tissue. The primary source of his cancer id likely to be the prostate.

3. What is the difference between class I and class II MHC proteins?

Class I MHC proteins are found on virtually all of the body's cells, while class IIs are found only on antigen-presenting cells. Class Is display antigens for recognition to CD8 T cells. Class IIs display antigens to CD4 T cells.

3. What other tests might be of some diagnostic help here?

Digital examination of his prostate should detect the presence of carcinoma in this tissue. In addition, transrectal ultrasound imaging may be used in screening, and biopsies of prostate tissue follow positive results of tests.

Chapter 29 Mrs. Rodriguez: She went on to have a normal pregnancy without complications. During her treatment in the hospital, she discovered that her blood is type O.

During one of her regular visits to her doctor, she asked what type of blood her baby will have, given that her husband's blood type is type A. Her doctor explained to her that she would need to know more about the blood type of Mr. Rodrigues's parents.

Chapter 10 Mrs. Tanner: Six weeks after the injury, she reported that she was still unable to walk or run without hip pain, and had weakness in her hip, knee, and ankle. Mrs. Tanner walked with a limp that her doctors attributed to weaknesses in flexion at the knee, inversion of the foot, and plantar flexion.

Electromyography (which measures muscle electrical activity) and nerve conduction studies (which measure the speed of nerve impulses) revealed that Mrs. Tanner's sciatic nerve had been damaged as a result of her injuries - most likely as a result of the nerve being compressed when the hip was dislocated. This large nerve innervates a large number of lower limb muscles. Since her surgery, Mrs. Tanner has been undergoing intense physical therapy and has shown significant improvement.

2. On what basis did you come to this conclusion?

Elevation of PSA levels suggests carcinoma of the prostate. (In addition, his age places him in a group that is at relatively higher risk for this type of cancer.)

3. Explain the cause and consequence of each of the hematology findings.

Elevation of renin, aldosterone, and antidiuretic hormone indicate that his body is trying to compensate for his falling blood pressure and blood loss. Renin: released when renal blood flow is diminished and blood pressure fall. The angiotensin-aldosterone response is initiated by renin. The formation of angiotensin II leads to vasoconstriction, which will increase blood pressure, and to the release of aldosterone. Aldosterone: increases Na+ reabsorption by the kidney. The movement of this reabsorbed Na+ into the bloodstream will promote the movement of water from the interstitial fluid, resulting in an increase in blood volume. Antidiuretic hormone (ADH): released when the hypothalamic osmoreceptors sense an increase in osmolality. ADH had two consequences: It is a potent vasoconstrictor and will increase blood pressure, and it promotes water retention by the kidney, increasing blood volume.

Chapter 18 Donald Ayers, a 49-year-old male, was the driver of the bus involved in the accident. He was brought into the ER with blunt trauma to the chest. Paramedics noted that the driver's seatbelt had broken and that he was found lying under the instrument panel. Initially unresponsive, Mr. Ayers regained consciousness and complained of chest, epigastric, and left upper quadrant pain.

Examination revealed mild tachycardia (110bpm) and a blood pressure of 105/75 mm Hg. An exam 10 minutes later showed a rapid change in blood pressure (80/55) and HR (130 bpm) along with muffled heart sounds, a thread (weak) pulse, and bulging neck veins. Soon after, the patient began to complain of a sudden onset of pain that radiated into his back from the injury site. The patient described the pain as "sharp, stabbing, and tearing" and it continued to increase.

7. How does Jimmy's excessively high blood pressure put him at risk?

Extremely high arterial blood pressure can cause a rupture of the cerebral blood vessels (as well as other blood vessels in the body) and put Jimmy's life at risk.

4. Describe the major developmental events and stages of embryonic development that have occurred during the time prior to her accident.

First, the egg released during the most recent ovulation is fertilized to form the zygote. Over the next week, embryonic development features many rapid rounds of cell division as the embryo moves through the uterine tube. Cleavage is the very early period of rapid cell division. By 72 hours after fertilization, the embryo is a ball of 16 or more cells called the morula. Around day 4, a fluid-filled cavity appears, which signals the formation of the blastocyst. Approximately one week after fertilization, the embryo has made its way into the uterus and begins the process of implantation.

4. What are the three membranes that make up the meninges? Describe their positions relative to the brain.

From the surface of the brain to the skull, the three membranes that make up the meninges include the pia mater, arachnoid mater, and dura mater.

3. Valium enhances the natural effects of the neurotransmitter GABA. What chemical class of neurotransmitters does GABA belong to? What are some of the other neurotransmitters that fall into this same class?

GABA falls into the amino acid class of neurotransmitters. This same class includes glycine, glutamate, and aspartate.

2. Where is the hormone made that you identified in question 1? What function does it play during the early stages of a pregnancy?

HCG is a hormone produced by the trophoblast cells that helps to maintain the viability of the corpus luteum. The corpus luteus is essential during early pregnancy because it is responsible for the production of estrogen and progesterone. These two hormones are required to maintain the uterus during the early stages of a pregnancy.

Chapter 14 On arrival at Holyoke Hospital, Jimmy Chin, a 10-year-old boy is immobilized on a rigid stretcher so that he is unable to move his head or trunk. The paramedics report that when the found him some 50 feet from the bus, he was awake and alert, but crying and complaining that he couldn't "get up to find his mom" and he had a "wicked headache."

He has severe bruises on his upper back and head and lacerations of his back and scalp. His blood pressure is low, body temperature is below normal, lower limbs are paralyzed, and he is insensitive to painful stimuli below the nipples. Although still alert on arrival, Jimmy soon begins to drift in and out of unconsciousness. Jimmy is immediately scheduled for a CT scan, and an operating room is reserved.

4. Given an uncomplicated recovery, approximately how long should it take before Mrs. DeStephano has a good solid bony callus?

Healing of Mrs. DeStephano's fracture will begin as bony callus formation fills the break in the bone with bony tissue. This process begins 3-4 weeks after the break occurs and is completed within 2-3 months.

4. Muffled heart sounds are quieter and less distinct. Explain how changes in EDV can result in muffled heart sounds.

Heart sounds are produced by the closing of heart valves during a normal cardiac cycle. When EDV is reduced, there is both reduced SV and reduced force of contraction, leading to slower, quieter valve closure.

CT scan reveals a ruptured spleen and a large hematoma in the upper left abdominal quadrant. Splenic repair surgery is scheduled but unsuccessful; the spleen is removed.

Hematology: Most blood tests yield normal results. However, renin, aldosterone, and ADH levels are elevated. Urinalysis: Some granular casts (particulate cell debris) are noted, and the urine is brownish-red in colour; other values are normal, but urine output is very low. An order is given to force fluids.

6. How do the recorded injuries related to the atelectasis?

Her fractured ribs probably punctured her lung tissue and allowed air within the lung to enter the pleural cavity.

2. What procedures (do you think) the emergency personnel should have initiated immediately?

Her head, neck, and torso should have been immobilized to prevent further damage to the spinal cord. In addition, she required assistance to breathe, so her airway was probably intubated to permit ventilation of her lungs.

5. What would happen if doctors had infused type B PRBCs into Mr. Malone's circulation?

His anti-B antibodies would have "attacked" these foreign cells and caused them to agglutinate. This transfusion reaction can be dangerous because the agglutinated cells can clog small vessels. In addition the transfused cells would begin to hemolyze (rupture) or would be sestroyed by phagocytes.

4. What type of therapy do you predict Mr. Heyden will be given to treat his carcinoma? Why?

His carcinoma has advanced to the point of metastasis. He will probably undergo a treatment that reduces the levels of androgens in his body, as androgens promote growth of the prostate-derived tissue. These treatments could include castration or administration of drugs that block the production and/or effects of androgens.

2. What would you say Mr. Gutteman's hormonal problem is and what do you think caused it?

His condition is termed diabetes insipidus, a condition in which insufficient quantities of antidiuretic hormone (ADH) are produced or released. Diabetes insipidus patients excrete large volumes of urine but do not have glucose or ketones present in the urine. The head trauma could have damaged his hypothalamus, which produces the hormone, or injured his posterior pituitary gland, which releases ADH into the bloodstream.

4. The production of large amounts of ketone bodies is often seen when glucose is not readily available as an energy source (eg. in starvation). In this case, large amounts of glucose are in the blood. Explain why his body is producing ketones in the presence of such large amounts of glucose.

His elevated blood glucose and his acidotic state indicates diabetes mellitus. In both type 1 and 2, the absence of insulin's actions means that the cells are unable efficiently take up and utilize glucose from the blood. As a result, blood glucose levels are high, yet the cells are forced to switch to an alternative energy source such as lipids, which results in the production of ketone bodies in a diabetic patient. The stress of alcohol-induced dehydration can trigger ketoacidosis b causing the release of stress hormones that make diabetes worse.

2. What do you think his diarrhea stems from? How will it be diagnosed and treated?

His responses to the questions reduced the possibility that he has gastric ulcers. His diarrhea may be due to gluten-sensitivity enteropathy. To verify this diagnosis, he should be screened for specific IgA antibodies in his blood. If these screening tests are positive, a biopsy of the intestinal mucosa would be performed. Observation of damaged intestinal villi and microvilli would confirm the diagnosis. A positive diagnosis of gluten-sensitivity enteropathy would lead to a lifelong dietary restriction of all grains except rice and corn. Grains should not be restricted prior to the biopsy.

1. Why is the new diet prescribed? (What is believed to be his problem?)

His statement about the effects of milk on his digestive tract suggests that he may be deficient in lactase, a brush border enzyme that breaks down lactose.

1. Given these values and his attendant cyanosis, what would you guess is his immediate problem?

His vital signs suggest that he is in hypovolemic shock, which is probably due to internal hemorrhage.

3. Beginning with the concept of end diastolic volume (EDV), explain the effect that the fluid in the pericardium is having on the stroke volume of Mr. Ayers's heart.

In cardiac tamponade, the fluid around the heart compresses the heart and prevents it from fully expanding as it relaxes (diastole). As a result of this restriction, less blood will flow into the heart (ventricular filling). With less blood flowing into the ventricles, the degree of stretch of the heart muscle (preload) will also be reduced. These events lead to a reduction in SV.

Chapter 7 Kayla Tanner, a 45-year-old mother of four, was a passenger on the bus involved in an accident on Route 91. When paramedics arrived on the scene, they found Mrs. Tanner lying on her side in the aisle. Upon examination, they found that her right thigh appeared shorter than her left thigh. They also noticed that even slight hip movement caused considerable pain. Suspecting a hip dislocation, they stabilized and transported her.

In the ER, doctors discovered a decreased ability to sense light touch in her right foot, and she was unable to move her toes or ankle. Dislocation of her right hip was confirmed by X-ray. Mrs. Tanner was sedated to relax the muscles around the hip, and then doctors placed her in the supine position and performed a closed reduction ("popped" the femur back in place).

5. Why were the recipients of the two kidneys put on immunosuppressive drug therapy?

In this case, the donor and recipients were not genetically identical. Even with very careful tissue typing and compatibility testing, there will still be some differences that the recipients' immune systems will recognize as foreign. To reduce the risk of organ rejection, the recipients are given drugs to suppress their immune systems.

4. Assuming that Barbara survives, how will her accident affect her lifestyle in the future.

Injury to the spinal cord at the level of the C2 vertebra will cause quadriplegia.

1. Mr. Ayers's pulse is described as "thready." What might this indicate with respect to this patient's stroke volume?

It indicates a drop in stroke volume. The pulse is felt as blood is ejected from the heard during ventricular contraction (systole). The weak and thread pulse suggests that less blood is being ejected during each contraction (a lower SV).

2. Tissue typing characterizes the class I and II MHC proteins. What is an MHC protein?

It is a type of cell surface protein that the human body uses to recognize self and to help coordinate the recognition of nonself, or foreign, antigens. These proteins are involved in the display of antigens to T cells.

4. Do you predict that Mr. Hutchinson's recovery will be uneventful or problematic? Why?

It may be problematic, as he probably already has an ongoing bacterial infection and his ability to raise a defense to this infection is impaired.

4. Two days after his surgery, Jimmy is alert and his MRI scan shows no residual brain injury, but pronounced swelling and damage to the spinal cord at T4. On physical examination, Jimmy shows no reflex activity below the level of the spinal cord injury. His blood pressure is still low. Why are there no reflexes in his lower limbs and abdomen?

Jimmy is suffering from spinal shock, which occurs as a result of injury to the spinal cord. Spinal shock is a temporary condition in which all reflex and motor activities caudal o the level of spinal cord injury are lost, so Jimmy's muscles are paralyzed. His blood pressure is low due o the loss of sympathetic tone in his vasculature.

5. Over the next few days, his reflexes return in his lower limbs and become exaggerated. He is incontinent. Why is Jimmy hyperreflexive and incontinent?

Jimmy's exaggerated reflexes are caused by damaged upper motor neuron axons in the spinal cord. These upper motor neurons normally inhibit spinal reflexes. He is incontinent because there are no longer pathways to support voluntary control of bowel and bladder emptying.

3. Where in the body are ketone bodies produced? What energy source does the body use to produce these substances?

Ketogenesis, or the production of ketone bodies, is a process that occurs primarily in hepatocytes when carbs are unavailable as an energy source. In this case, the hepatocytes metabolise fats. The fatty acids produced from fat breakdown are converted to acetyl CoA by beta oxidation. In the absence of glucose, these acetyl CoA molecules cannot enter the Kreb's cycle, and hepatocytes convert them into ketone bodies.

3. Assuming that Jimmy's sensory and motor deficits are due to a spinal cord injury, at what level do you expect to find a spinal cord lesion?

Loss of motor and sensory function below the level of the nipples indicates a lesion at T4.

2. Assuming that bacteria are penetrating the dermis in these areas, what remaining skin defenses might act to prevent further bacterial invasion?

Macrophages found in the dermis can act as a backup system against bacterial and viral invasion when the epidermis is damaged.

2. What are the three main sources of sensory input that the body uses in order to control balance and equilibrium?

Maintaining balance and equilibrium requires multiple sources of sensory input. The three main sources are the vestibular apparatus of the ear, visual input, and input for the proprioceptors of the skin, muscles, and joints.

4. What is the probability that Mrs. Rodriguez's baby will have O blood type? A? B? AB?

Mother: ii and Father IAi = 50% chance ii (O), 50% chance IAi (A), 0% chance B, 0% chance AB

Chapter 25 Kyle Boulard: After two days in hospital, he has recovered from his acute diabetic crisis and his type 1 diabetes is once again under control. The last update on his chart before he is discharged includes the following: - BP 150/95, HR 75, temperature 37.2 - urine: pH 6.9, negative for glucose and ketones; 24-hour urine collection reveals 170 mg albumin in urine per day

Mr. Boulard is prescribed a thiazide diuretic and an angiotensin converting enzyme (ACE) inhibitor. He is counseled on the importance of keeping his diabetes under control, taking his medications regularly, and keeping his outpatient follow-up appointments.

3. Mr. Rodriguez's mother has O blood type and his father has A blood type. Explain how this information helps you understand Mr. Rodriguez's genotype.

Mr. Rodriguez's genotype can be either IAIA or IAi. We know that his mother had O blood type, and that means that she carries two copies of the O blood type allele (ii). She must have passed on one of these alleles to her son. This means that his father must have passed on the allele for the A blood type. Mr. Rodriguez's genotype must be IAi.

1. What type of fracture does Mrs. DeStephano have?

Mrs. DeStephano's broken leg has a transverse fracture of the open variety because the broken ends of the bone are protruding through the skin.

6. Hip dislocations can be classified as anterior or posterior depending on which direction the head of the femur is facing after it dislocates. Based on the description you provided in Q. 5, which type of dislocation did Mrs. tanner suffer?

Mrs. Tanner suffered a posterior dislocation of the hip. when the head of the femur comes away from the acetabulum and then turns posteriorly, it causes the femur to rotate counterclockwise. This can be determined from the fact that her thigh was adducted and medially rotated.

5. What complications might be predicted by the fact that the nutrient artery is damaged?

Nutrient arteries supply blood to the bone tissue. In order for Mrs. DeStephano's break to heal normally, the bony tissue must be supplied with oxygen (to generate ATP for energy) and nutrients in order to rebuild the bone. Damage to a nutrient artery will decrease the delivery of these building materials and could slow the process of healing.

3. Why was the physician able to use O negative blood before the results of the blood type tests were obtained?

O negative blood cells bear neither the A nor the B nor the Rh agglutinogens (antigens). People with O negative blood are sometimes called "universal donors" because their cells lack the antigens responsible for most major transfusion reactions.

Chapter 26 Mr.Heyden, a somewhat stock 72-year-old man, is brought in to the ER. The paramedics report that his left arm and the left side of his body trunk were pinned beneath some wreckage, and that when he was feed, his left hypogastric and lumbar areas appeared to be compressed and his left arm was blanched and without sensation.

On admission, Mr. Heyden is alert, slightly cyanotic, and complaining of pain in his left side; he loses consciousness shortly thereafter. His vital signs are taken, blood is drawn for lab tests, and he is catheterized and immediately scheduled for a CT scan of his left abdominal region. Analyze the information that was subsequently recorded on his chart: - vital signs: temp 39; BP 90/50 and falling; HR 116 and thread; 30 respirations/min

Chapter 28 Maria Rodriguez: a 34-year-old female, found lying on the edge of the road. She was responsive, but had deep lacerations on both legs and her right arm. Her clothes were heavily stained with blood, despite the efforts of another passenger to slow the bleeding by applying compression.

On initial examination, her BP was 100/70, HR 88. The paramedics started an IV of normal saline, stabilized her, and controlled the bleeding during transport to the hospital. She was released from the hospital three days later and scheduled for a follow-up visit in one week. At her follow-up appointment, she complained of fatigue and reported that her period was overdue by one week. Hospital tests revealed that she was mildly anemic - and pregnant. While she was excited, she was also very concerned that the blood loss she suffered may have harmed her baby.

Mr. Gutteman's problem continues despite the diet change. In fact, the frequency of diarrhea increases and by the end of the next day, he is complaining of severe abdominal pain. Again, he is asked some questions to probe his condition. One is whether he has traveled outside the country recently. He has not, reducing the possibility of infection with Shigella bacteria, which is associated with poor sanitation.

Other questions: - Do you drink alcohol and how much? (Litlle or none.) - Have you recently eaten raw eggs or a salad containing mayonnaise at a gathering? (No.) - Are there certain foods that seem to precipitate these attacks? (Yes, when I have coffee and a sandwich.)

Chapter 24 Kyle Boulard, a 35-yer-old male, is believed to be one of the primary causes of the accident on Route 91. Passengers on the bus reported that he was clearly intoxicated when he boarded the bus. According to these reports, he behaved erratically, appeared disoriented, and left his seat and staggered down the aisle. Just prior to the accident, he had stumbled into the driver's compartment.

Paramedics found him in a disoriented state when they arrived on the scene, but noted only minor injuries. A "fruity acetone combined with alcohol" smell was noted on his breath. What follows is a summary of the notable test results. - BP: 95/58; HR 110 bpm - Blood pH: 7.1; Glucose: 345 mg/dl; Keone bodies: 22 mg/dl; blood alcohol 110 mg/dl - urine odour: "fruity acetone"; pH 4.3; glucose - strongly positive

3. What is internal reduction? Why was a cast applied?

Reduction of a fracture is the clinical term for "setting the bone." Mrs. DeStephano's physician chose internal reduction, in which surgery is performed and the broken ends of the bone are secured together by pins or wires. A cast was applied to keep the aligned ends of the bone immobile until healing of the fracture has occurred.

1. How might the "peculiar" head position explain Barbara's cessation of breathing?

Spinal cord injury from a fracture at the level of the C2 vertebra would interrupt the normal transmission of signals from the brain stem down the phrenic nerve to the diaphragm, and Barbara would be unable to breathe due to paralysis of the diaphragm.

4. Surgeons had to remove a portion of Mrs. Tanner's acetabular labrum. What is this structure and what function does it supply at this joint?

The acetabular labrum is a piece of fibrocartilage that attaches to and extends the rim of the acetabulum. The diameter of the labrum is less than the diameter of the head of the femur, and this helps stabilize the joint to prevent it from dislocating.

5. Explain why nystagmus is associated with the Dix-Hallpike manoeuvre.

The added mass of the displaced otoliths pushes on a cupula of a semicircular canal when the head is rotated during the Dix-Hallpike manoeuver. The otoliths either stick to the gelatinous cupula, or swirl through the canals during head movement and drift against the cupula like snow. In both cases, the bending of the cupula is prolonged and vertigo persists. As a result, vestibular nystagmus is observed when it would ordinarily be absent.

5. Mrs. Rodriguez is currently in the third week of pregnancy. Describe the important embryonic developmental event that occurs during this time.

The embryo transforms into a three-layered structure as the result of a process called gastrulation. This process involves the rearrangement and migration of cells as the three primary germ layers (ectoderm, mesoderm, and endoderm) are formed. These layers serve as the primitive tissues from which all of the body organs will be formed as development continues.

7. In order to assess the joint as part of Mrs. Tanners rehabilitation, clinicians would want to assess all of the movements that normally occur at the hip. List all the movements that the clinicians will need to assess.

The hip movements include flexion, extension, abduction, adduction, rotation, and circumduction of the thigh.

Chapter 5 Examination of Mrs. DeStephano, a 45-year-old woman, reveals several impairements of homeostasis. Relative to her integumentary system, the following comments are noted on her chart: - epidermal abrasions of the right arm and shoulder - severe lacerations of the right cheek and temple - cyanosis apparent

The lacerated areas are cleaned, sutured (stitched), and bandaged by the emergency room (ER) personnel, and Mrs. DeStephano is admitted for further tests.

3. How might the low lymphocyte count, megadoses of antibiotics, and orders for additional clinical staff protection be related?

The low lymphocyte count indicates that his body's ability to fight infection by bacteria or viruses is impaired. the antibiotics and additional staff protection will protect him until his lymphocyte count increases again. Gloving and gowning also protect the staff caring for him for any body infection he might have.

Chapter 21 Mr. Ayers: Although his dissected aorta was repaired, by the time surgical exposure and blood vessel clamping had been achieved, the dissection had extended up into the origin of his left common carotid artery. As a result, a clot had formed that caused a massive stroke. Unfortunately, this left him with severe and permanent brain damage, and he was declared brain dead. A discussion of Mr. Ayers's situation with his family confirmed his status as an organ donor.

The organ recovery coordinator evaluated Mr. Ayers's suitability as a candidate for organ donation. Tissue typing (histocompatibility) tests were conducted, and the results were entered into the UNOS database. Two potential recipients were identified. Mr. Ayers's right kidney was given in transplantation to a 35-year-old man, and his left kidney was given to a 27-year-old woman. Following surgery, both recipients were placed on immunosuppressive drug therapy.

5. Explain how the pH of his blood and urine is related to the ketone bodies measured in each of these fluids.

The pH of his blood and urine is abnormally low because ketone bodies are acidic. As the concentration of ketone bodies in the blood rises, the blood pH falls (acidosis). The kidneys correct the blood pH by moving ketones bodies into the urine, making acidic urine.

2. Name the six distinguishing features that define the structural classification of the joint involved in this injury?

The six distinguishing features that define a synovial joint are: 1) articular cartilage, 2) joint (synovial) cavity, 3) articular capsule, 4) synovial fluid, 5) reinforcing ligaments, 6) nerves and blood vessels.

1. What protective mechanisms are impaired or deficient in the abraded areas?

The skin separates and protects the internal environment of the body from potentially dangerous elements in the external environment. Mrs. DeStephano's chart indicates epidermal abrasions, which represent the loss of this barrier. Epidermal loss will also cost Mrs. DeStephano the acid mantle of her skin, protection against UV radiation, and dendritic cells, which protect against invasion by microorganisms.

2. Rupture of the spleen results in massive haemorrhage. Explain this observation. Which organs (if any) will compensate for the removal of his spleen?

The spleen is a highly vascular organ due to its role as a blood-filtering organ. the macrophages in his liver and bone marrow will help compensate for the loss of his spleen.

6. Mrs. Tanner's injury caused damage to the sciatic nerve that passes across the hip and down into the thigh, lower leg, and foot. Name the pelvic structure that this nerve passes through as it travels into the upper thigh.

The structure of the pelvis that the sciatic nerve passes through as it travels into the upper thigh is the greater sciatic notch of the ilium.

3. Name the two functional divisions of the vestibular apparatus. Identify the sensory receptor associated with each division, and state which aspect of equilibrium each receptor senses.

The two functional divisions are the vestibule and semicircular canals. The vestibule's sensory receptors are the maculae, which sense linear acceleration and deceleration. The semicircular canals' receptors are the cristae ampullares, which detect rotational acceleration and deceleration.

2. What do his worsening neurological signs (drowsiness, incoherence, etc.) probably indicate? Relate this to the type of surgery that will be performed.

The worsening neurological signs indicate a probable intracranial hemorrhage. The blood escaping from the ruptured blood vessel(s) will begin to compress Jimmy's brain and increase his intracranial pressure. Jimmy's surgery will involve repair of the damaged vessel(s) and removal of the mass of clotted blood pressing on his brain.

2. Why were these medications prescribed for him?

These medications were prescribed to treat his hypertension. Both diabetes and hypertension can cause kidney damage, and hypertension is a major cause of other cardiovascular diseases such as heart failure and stroke. Albuminuria indicates that he already had damage to his kidneys, so it is important to protect his kidneys from further damage.

1. Relative to what you have learned about tissue requirements for oxygen, what is the condition of the tissues in the right lower limb?

They were deprived of oxygen and nutrients for at least one-half hour. When tissues are deprived of oxygen, tissue metabolism decreases and eventually ceases, so these tissues may have died due to anoxia.

5. Explain how the thiazide diuretic might have caused this problem.

Thiazide diuretics increase Na+ excretion and decrease blood pressure. To compensate for these effects, his renin-angiotensin-aldosterone mechanism is activated. Aldosterone increases Na+ reabsorption and K+ secretion, resulting in hypokalemia (low blood K+).

3. Where and how do thiazide diuretics act in the kidneys and how does this reduce blood pressure?

Thiazide diuretics increase urine output by inhibiting Na+ reabsorption in the DCT. This decreases blood volume, which decreases blood pressure.

On one occasion, Jimmy complains of a massive headache and his blood pressure is way above normal. On examination, he is sweating intensely above the nipples but has cold, clammy skin below the nipples and his heart rate is very slow. 6. What is this condition called and what precipitates it?

This condition is called autonomic dysreflexia. This is a condition in which a normal stimulus triggers a massive activation of autonomic neurons.

4. Using descriptions similar to those listed in the question above, explain how you would assess the function of the following muscles. a) extensor halluces longus

This muscle inserts on the distal phalanx of the great toe. The therapist can apply resistance to the top of the toe and ask Mrs. Tanner to extend the toe.

4. b) Fibularis (peroneus) longus

This muscle is involved in eversion of the foot and plantar flexion. The therapist can apply resistance to the lateral part of the foot and ask Mrs. Tanner to evert (turn out) her ankle. In addition, resistance can be applied to the bottom of the foot and Mrs. Tanner asked to push against that resistance.

3. What complications in muscle structure and function result from transection of the sciatic nerve? Why are passive ROM and electrical stimulation of her right leg muscles ordered?

Under normal circumstances, skeletal muscles receive electrical signals from the nervous system continuously. These signals help to maintain muscle tone and readiness. Severing of the sciatic nerve removes this continuous nervous input to the muscles and will lead to muscle atrophy. Immobility of muscles will lead to a replacement of contractile muscle tissue with noncontractile fibrous connective tissue. Distal to the point of transection, the muscle will begin to decrease in size within 3-7 days of becoming immobile. This process can be delayed by electrically stimulating the tissues. Passive ROM exercises also help prevent loss of muscle tone and joint range, and improve circulation in the injured areas.

Chapter 20 Back to following the progress of Mr. Hutchinson, se learn that the routine complete blood count (CBC) performed on admission reveals that his leukocyte count is dangerously low and follow-up lab tests show that his lymphocytes are deficient. One day postsurgery, he complains of pain in his right ring finger (that hand had a crush injury).

When examined, the affected finger and the dorsum of the right hand are edematous, and red streaks radiate superiorly on his right forearm. Higher-than-normal doses of antibiotics are prescribed, and a sling is applied to the affected arm. Nurses are instructed to wear gloves and gown when giving Mr. Hutchinson his care.

4. What is Mr. Boulard's main problem at this point?

While he still has hypertension, his main problem is that his blood K+ is low. He is losing too much K+ in his urine. This is the underlying cause of his irregular heartbeat, which could turn into a fatal arrhythmia if his hypokalemia is not corrected.

7. Would taking ACE inhibitors and thiazides together have prevented Mr. Boulard's current symptoms?

Yes. The ACE inhibitors would have prevented the formation of excess angiotensin II and the resulting release of aldosterone. This would have lessened excess secretion of K+.

4. a) What might account for the low volume of urine output?

a) His urine production may be decreased for several reasons. The severe drop in his blood pressure would reduce renal blood flow, thus reducing glomerular blood pressure and decreasing his glomerular filtration rate. The elevation in his ADH levels can reduce urine output due to increased water reabsorption by the kidney. He may also have damage to the kidney due to his crush injury in the left lumbar region.

4. b) What might explain the casts and abnormal colour of his urine? Can you see any possible relationship between his crush injury and these findings?

b) The presence of casts and a brownish-red colour in his urine are probably due to damaged cells and blood. If he has suffered kidney damage due to being crushed, he may have nephron damage that would include disruption of the filtration membrane, allowing RBCs to pass into the filtrate and therefore the urine. He may also have damaged renal tubules and peritubular capillaries, allowing entry of blood and damaged renal tubule epithelial cells into the filtrate.

Case Studies

A terrible collision between a trailer truck and a bus has occurred on Route 91. Several of the passengers are rushed to area hospitals for treatment. We will follow a few of these people in clinical case studies that will continue through the book from one organ system to the next.

Chapter 19 Mr. Hutchinson, another middle-aged victim of the collision on Route 91, has a tourniquet around his thigh when admitted in an unconscious state to Noble Hospital. The emergency technician who brings him in states that his right lower limb was pinned beneath the bus for at least 30 minutes. He is immediately scheduled for surgery.

Admission notes include the following: - multiple contusions of lower limbs - compound fracture of the right tibia;; bone ends covere with sterile gauze - right leg blanched and cold, no pulse - blood pressure 90/48; pulse 140/min and thread; patient diaphoretic (sweaty)

2. Mr. Ayers's HR increased from 100 to 130 bpm. What effect will this have on his cardiac output?

An increase: CO = HR x SV. His CO is abnormally low (as shown by his decreasing blood pressure). This is probably due to a decrease in SV. The increase in HR is an attempt to compensate for the decrease in SV in order to maintain CO as close to normal as possible.

5. Valium actually works postsynaptically to promote binding of GABA to its receptor, thereby enhancing the influx of Cl- ions into the postsynaptic cell (the natural effect produced by GABA). Why would this effect reduce the likelihood that this cell would be able to produce an electrical signal?

An influx of Cl- into the postsynaptic cell causes the membrane potential to become more negative (hyperpolarize). When hyperpolarized, the cell is farther from its threshold potential and so is less likely to produce an action potential.

2. Valium enhances inhibitory postsynaptic potentials (IPSPs). What is an IPSP? How does it affect action potential generation?

An inhibitory postsynaptic potential (IPSP) is a signal that makes it less likely that a postsynaptic neuron will be able to generate an action potential. This effect is usually produced when the signal causes the membrane potential of the postsynaptic neuron to become more negative, moving away from the axon's threshold potential.

1. In addition to blood, which fluid was leading from Mr. Hancock's right ear? Which structures must have been damaged to allow this to happen? Why would this lead Mr. Hancock's doctors to give him antibiotics? Why was the head of his bed elevated?

Cerebrospinal fluid (CSF) is leaking out of Mr. Hancock's right ear. The fracture must have torn both the dura mater and arachnoid mater. In addition, the tympanic membrane must have ruptured. Antibiotics were administered to prevent infection by bacteria that might enter through the ruptured meninges, causing meningitis. Elevating the head of the bed decreases the CSF pressure in the skull. (This allows the torn meninges to heal spontaneously in the majority of cases.)

3. Is it life threatening?

Diabetes insipidus is not life threatening for most individuals with normal thirst mechanisms, as they will be thirsty and drink to replenish the lost fluid. However, Mr. Gutteman is comatose, so his fluid output must be monitored closely so that the volume lost can be replaced by IV line. His subsequent recovery may be complicated if he has suffered damage to his hypothalamus, which houses the thirst center neurons.

Chapter 16 Mr. Gutteman, a 70-year-old male, was brought into the ER in a comatose state and has yet to come out of it. It is obvious that he suffered severe head trauma - his scalp was badly lacerated, and he has an impacted skull fracture. His initial lab tests (blood and urine) were within normal limits.

His fracture was repaired and the following orders (and others) were given: - Check qh (every hour) and record: spontaneous behavior, level of responsiveness to stimulation, movements, pupil size and reaction light, speech, and vital signs - turn patient q4h and maintain meticulous skin care and dryness

3. Mrs. Tanner's physical therapist performed a variety of assessments in order to establish a baseline from which her recovery could be measured. For each of the descriptions below, name the muscle (or muscles) that the therapist was assessing. a) With Mrs. Tanner in the seated position, the therapist positioned her legs shoulder-width apart, then asked her to bring her feet together while the therapist applied resistance to the right leg.

Ideally, the therapist would assess each muscle individually. In reality, these assessments usually measure the function of a group of muscles because multiple muscles are often involved in similar actions. - thigh adductors, pectineus and gracilis. Specifically, the adductor magnus is innervated by the damaged nerve.

2. Why is it important that he not move the affected arm excessively?

Immobilizing it slows the drainage of lymph from the affected area in an attempt to limit the spread of the infection.

6. Why did Mr. Ayers's neck bulge?

In the face of reduced SV, blood returning to the heart backs up, leading to a rise in venous pressure. This is a key sign of tamponade.

4. Mr. Malone's blood type was determined to be A positive. What plasma antibodies (agglutinins) does he have, and what type of blood can he receive?

It would have anti-B antibodies so he would nt be able to receive B or AB blood. He can safely receive A and O blood.

On the second day of his hospitalization, the aide reports that Mr. Gutteman is breathing irregularly, his skin is dry and flaccid, and that she has emptied his urine reservoir several times during the day. Upon receiving this information, the physician ordered: - blood and urine tests for presence of glucose and ketones - strict I&O (fluid intake and output recording)

Mr Gutteman is found to be losing huge amounts of water in urine and the volume lost is being routinely replaced (via IV line). Mr. Gutteman's blood and urine tests are negative for glucose and ketones.

Chapter 15 When emergency personnel arrived on the scene of the bus crash, they found Brien Rhen, 42, sitting on the side of the road holding his head in his hands/ He complained of a severe headache and nausea, and was evaluated and treated for a concussion. Several days later, Mr. Rhen began to experience recurring episodes of vertigo and was referred to a neurologist. (Vertigo is a sensation of motion or movement while the person is stationary, and can be accompanied by nausea and vomiting.)

Mr. Rhen was diagnosed with benign paroxysmal positional vertigo (BPPV). With this condition, which can be caused by head trauma, vertigo can be provoked by specific changes in head position. He reported that his vertigo usually occurred when rolling over in bed, or when turning his head from side ot side while sitting up, and that these movements provoked the sensation of a spinning room, which led to nausea. The neurologist confirmed the diagnosis of BPPV by using a test called the Dix-Hallpike manoeuvre. During the test, the neurologist looks for nystagmus (involuntary, jerking eye movements) as he makes specific rotational changes to Mr. Rhen;s head position.

4. BPPV can be caused by otoliths that have been dislodged from the otolithic membrane of the maculae. Based on Mr. Rhen;s symptoms and the head movements that provoke these symptoms, what part of the vestibular apparatus are the displaced otoliths now affecting?

Mr. Rhen's vertigo is brought on by rotational movements of the head, suggesting that the cristae ampullares of the semicircular canals are affected.

Chapter 8 Mrs. Tanner: Prior to the closed reduction, the doctors noted that her right thigh was flexed at the hip, adducted, and medially rotated. After the reduction, the hip was put through a gentle range of motion (ROM) to assess the joint. A widened joint space in the postreduction X ray showed that the reduction was not complete, but no bone fragments were visible in the joint space.

Mrs. Tanner was scheduled for immediate surgery. The surgeons discovered that the acetabular labrum was detached from the rim of the acetabulum and was lying deep with the joint space. The detached portion of the labrum was excised, and the hip was surgically reduced. During the early healing phase (first two weeks), Mrs. Tanner was kept in traction with the hip abducted.

5. The doctors noted that Mrs. tanner's thigh was flexed at the hip, adducted, and medially rotated. Describe what this means in terms of the position of her leg.

Mrs. Tanner's hip was bent (flexed) and her thigh was pulled toward the midline of her body (adducted) and turned in toward this midline (medially rotated).

1. Mr. Malone was going into shock because of blood loss, so paramedics infused a saline solution. Why would this help?

Saline infusion temporarily replaces the lost blood volume, thereby helping to restor his circulation.

Chapter 11 Elaine Sawyer, 35, was on her way to the local elementary school with her three children when the accident on Route 91 occurred. As Mrs. Sawyer swerved to avoid the bus, the right rear corner of her minivan struck the side of the bus, causing the minivan to tip over and slide on its side. Her children were shaken but unhurt. Mrs. Sawyer, however, suffered a sever head injury that caused post-traumatic seizures.

The drugs initially prescribed for her treatment were insufficient to control these seizures. Her doctor additionally prescribed Valium, but suggested that she use it only for a month because Valium induces tolerance. After a month of Valium treatment, Mrs. Sawyer no longer had seizures and gradually reduced and eliminated her use of Valium. After being seizure-free for another year, restrictions on her driver's license were lifted.

1. The ear is divided into three major areas (compartments). What are these three areas, and which of these areas is involved in Mr. Rhen's BPPV?

The ear is divided into three major area: external ear, middle ear, and internal ear. The portion of the internal ear, or labyrinth, associated with balance and equilibrium is the part of the ear affected in Mr. Rhen's BPPV.

1. Seizures reflect uncontrolled electrical activity of groups of neurons in the brain. Valium is described as a drug that can "quiet the nerves," which means that it inhibits the ability of neurons to generate electrical signals. What are these electrical signals called, and what is happening at the level of the cell when they are generated?

The electrical signals generated by neurons are call action potentials. An action potential is a change in membrane potential that involves depolarization and repolarization phases.

5. The final diagnosis in this case is a dissection (tear) of the aorta. From what you know about the anatomy of the heart, where in the aorta do you think the tear is located?

The enlarged mediastinum and pericardial effusion suggest that the bleeding is restricted within these compartments. The tear would most likely be located in the proximal portion of the ascending aorta (the part closest to the heart). This part of the aorta is located within the pericardium. The tear then proceeded distally but was contained with the aortic wall, causing the back pain. An uncontained tear in the aortic arch or descending aorta would lead to bleeding in the thoracic and/or abdominal cavities, which was not observed in this case.

3. The observations after 24 hours suggest that yet another cranial nerve has been damaged. Which one? How can you explain the lack of tear production in the right eye?

The facial nerve (CN VII) is the primary motor nerve associated with facial expression. The facial nerve also contains parasympathetic fibers that control secretion of tears from the lacrimal glands. Damage to this nerve explains both the motor symptoms and the dryness of his eye.

1. Describe the step-by-step process of wound healing that will occur in her fleshy (muscle) wounds, and note the consequences of the specific restorative process that occurs.

The first reaction to tissue injury is the initiation of the inflammatory response. The inflammatory chemicals increase the permeability of the capillaries in the injured area, allowing white blood cells, fluid, and other substances to reach the injured area. The next step in healing involves the formation of granulation tissue, in which the vascular supply for the injured are is regenerated and collagen fibers that knit the torn edges of the tissue together are formed. Skeletal muscle does not regenerate well, so the damaged areas of Mrs. DeStephano's muscle tissue will probably be repaired primarily by the formation of fibrous tissue, creating scar tissue.

Chapter 13 William Hancock, a 44-year-old male, was a passenger on the bus involved in the accident on Route 91. When emergency personnel arrived on the scene, they found Mr. Hancock unconscious, but with stable vital signs. As paramedics place him on a blackboard to stabilize his head, neck and back, they noted watery blood leaking from his right ear. In the hospital, he regained consciousness and was treated for deep lacerations on his scalp and face. Head CT scans revealed both longitudinal and transverse fractures of the right petrous temporal and sphenoid bones that extended through the foramen rotundum and foramen ovale.

The following observations were recorded on Mr. Hancock's chart on admission: - Complete loss of hearing in the right ear - Paresthesia (sensation of "pins and needles") at the right corner of the mouth, extending to the lower lip and chin - numbness of the right upper lip, lower eyelid, and cheek - right eye turned lightly inward when looking straight ahead. Diplopia (double vision), particularly when looking to the right. Mr. Hancock was given a course of antibiotics, the head of his bed was elevated by 30 degrees, and he was placed under close observation. After 24 hours, doctors noted that the right side of Mr. Hancock's face showed signs of drooping, with incomplete eye closure and asymmetric facial expressions. Mr. Hancock's right eye showed minimal tear production. The weakness and asymmetry on the right side of his face began to subside after a few days, and the leak of fluid from his ear stopped, but he continued to complain of paresthesia, diplopia, and an inability to hear with his right ear.

2. What problems can be predicted with such fractures and how are they treated?

The laceration of the skin caused by the broken end of the bone creates a breach in the protective barrier created by the skin, providing an entry point for bacteria and other microorganisms. In addition, the protruding ends of the bone have now been exposed to the nonsterile external environment. This could result in the development of osteomyelitis, a bacterial infection, which can be treated with antibiotics.

2. Which side of the brain is involved in Mrs. Bryans's injury? What evidence did you use to determine this?

The left side of the brain has been affected in this case. The motor dysfunction on the right side of the body is the primary piece of evidence used to determine this. In addition, the brain areas serving speech are usually located in the left side.

Chapter 17 Earl Malone is a 20-year-old passenger on the bus. Upon arrival at the scene, paramedics make the following observations: - right upper quadrant abdominal pain - cyanotic - cool and clammy skin - blood pressure 100/60 and falling, pulse 100 Paramedics start and IV to rapidly infuse a 0.9% sodium chloride solution (normal saline). They transport him to a small rural hospital where Mr. Malone's blood pressure continues to fall and his cyanosis worsens.

The local physician begins infusing O negative packed red blood cells (PRBCs) and arranges transport by helicopter to a trauma center. She sends additional PRBC units in the helicopter for transfusion en route. After arrival at the trauma center, the following notes were added to Mr. Malone's chart: - abdomen firm and distended - blood drawn for typing and cross matching; packed A positive blood cells infused emergency FAST (Focused Assessment with Sonography for Trauma) ultrasound is positive for intraperitoneal fluid A positive FAST scan indicates intra-abdominal bleeding. Mr. Malone's condition continues to deteriorate, so he is prepared for surgery, which reveals a lacerated liver. The laceration is repaired, and Mr. Malone's vital signs stabilize.

1. Why were his head and torso immobilized for transport to the hospital?

The location of Jimmy's lacerations and bruises and his inability to rise led the paramedics to suspect a head, neck or back injury. They immobilized his head and torso to prevent any further damage to the brain and spinal cord.

3. What specific parts of the region of the brain you identified in question 1 are being affected by the injury to cause the muscle weakness and language problems?

The motor dysfunction on the right side of the body suggests that the injury has affected the primary motor cortex and possible the premotor cortex of the left cerebral hemisphere. In addition to the problems with motor function, Mrs. Bryans experienced difficulty with language. Two areas of the brain associated with language, Boca's and Wernicke's area, are usually located in the left cerebral cortex. The type of aplasia described suggests damage to Boca's area.

2. Each of the four observation on Mr. Hancock's chart indicates damage to a cranial nerve. Identify each cranial nerve involved. If applicable, identify which specific branch of that nerve is involved.

The observations on Mr. Hancock's chart indicate: a) either damage to CN VIII (transmits afferent impulses for the sense of hearing) or destruction of the cochlea (the sensory organ for hearing); b) damage to CN V, which runs through the foramen ovale. This nerve conveys sensory information from the lower part of the face; c) Damage to CN V2, which runs through the foramen rotundum. This nerve conveys sensory information from the skin of the upper lip, lower eyelid, and cheek; d) damage to CN VI, which innervates the lateral rectus muscle of the eye. Because this muscle is responsible for pulling the eye laterally, loss of tone in this muscle at rest will cause the eye to turn inward. Diplopia will worsen when looking to the right because the eye cannot abduct.

2. Name the structure on the femur that forms the "ball" that fits into the "socket" you named in question 1.

The structure on the femur that forms the "ball" that fits into the "socket" named in question 1 is called the head of the femur.

5. The sedation that Mrs. Tanner was given was to relax the large muscles of the thigh and buttocks that attach to the proximal end of the femur. Name the structures on the femur where these muscles attach.

The structures on the femur where the large muscles of the buttocks and thigh attach are the great4eer trochanter and lesser trochanter.

5. Relative to the meninges, describe the location of the bleeding revealed on the CT scan.

The subarachnoid hemorrhage involves bleeding into the region below the arachnoid mater. The subdural hematoma involves blood collecting between the dura mater and the arachnoid mater.

3. There are three bones in the pelvic girdle that fuse together at a point within the structure that you named in question 1. Name those three bones.

The three bones in the pelvic girdle that fuse together at a point within the structure identified in question 1 are the ilium, ischium, and pubis.

2. Will the fracture be attended to, or will Mr. Hutchinson's other homeostatic needs take precedence? Explain your answer choice and predict his surgical treatment.

The vital signs indicate that he is facing a life-threatening problem that must be stabilized before other, less vital problems can be addressed. As for surgery, he may be scheduled for open reduction of his crushed bone, depending upon the condition of the tissues in his crushed right leg. If tissue death has occurred in his let, he may undergo amputation of that limb.

3. What do you conclude regarding Mr. Hutchinson's cardiovascular measurements, and what measures do you expect will be taken to remedy the situation before commencing surgery?

They indicate hypovolemic shock, a type of shock resulting from decreased blood volume. Because his blood volume is low, his heart rate is elevated to increase cardiac output in an effort to maintain the blood supply to his vital organs. His blood volume must be increased as quickly as possible with blood transfusions or IV saline. This will stabilize his condition and allow his physicians to continue with his surgery.

1. What do the red streaks emanating from the bruised finger indicate? What would you conclude his problem was if there were no red streaks but the right arm was very edematous?

They indicate that his lymphatic vessels are inflamed. This inflammation may be caused by a bacterial infection. If his arm had exhibited edema without any accompanying red streaks, the problem would likely have been impaired lymph transport from his arm back to his trunk, due to injury or blockage of his lymphatic vessels.

3. b)The therapist applied resistance to the top of Mrs. Tanner's foot and asked her to pull her forefoot up toward her shin.

This addresses the ability to dorsiflex the foot. Dorsiflexion involves all of the muscles in the anterior compartment of the lower let: the tibialis anterior, extensor digitorum longus, fibularis (peroneus) tertius, and extensor halluces longus.

4. Theoretically, there are a number of possible ways that a drug such as Valium could act to enhance the action of GABA. What are three such possibilities?

To enhance the actions of GABA at a synapse, a drug could either 1) act presynaptically to increase the release of GABA at the synapse, 2) decrease the reuptake of GABA after it has been released, or 3) act postsynaptically to either increase the binding strength of GABA at its receptors, or increase the number of receptors.