Chapter 9_ Anesthesia
Reversal of muscle relaxants agents
"anticholinergics" atropine robinul
MH triggered by
-Use of succinylcholine, curare, halogenated inhalation agents -Strenuous exercise, stress, trauma
Physical status codes
ASA 1: normal healthy pt ASA 2: mild systemic disease that's controlled and doesn't limit activities ASA 3: moderate to severe systemic disease, possibly uncontrolled, can alter activities ASA 4: severe systemic disease that is a constant threat to life ASA 5: morbid and substantial risk of death within hours with or without intervention E: emergency status or undergoing emergency procedure (added to ASA code)
Risks of General Anesthesia
Aspiration Cardiac dysrhythmias Cardiac arrest Laryngospasm/ Bronchospasm Allergic reactions Shock Malignant Hypothermia
Patients hard to intubate
COPD, asthmatic -Need respiratory treatment first
Anesthetic state
Characterized by unconsciousness and insusceptibility to pain produced by anesthetic agent or combination of agents
Narcotic analgesics
Controlled substances given to minimize perception of pain and to potentiate anesthesia; usually given 1 hour prior to surgery in order to have peak effect Ex. Demerol, morphone
Selection of anesthesia based on:
Current physical status Presence of metabolic disease Psychological status Type and length of procedure Past history of adverse reactions Preference of doc, pt
Histamine 2/ antacid blockers
Decrease gastric acidity and volume Ex. Tagamet, Zantac, bicitra
Agent inhalation
Delivery of gases that cross the Alveolar membrane to the vascular system where the agent can affect the CNS functions
Airway management
Endotracheal tube Laryngeal airway mask Oropharyngeal airway Nasopharyngeal airway Nasal cannula Oxygen mask
Non traditional anesthesia options
Hypnoanesthesia Acupuncture
Phase 1: Induction
Induction agents, IV agents or Inhalation agents are administered and loss of consciousness occurs and usually a muscle relaxant. Management of Airway is critical and may involve ET tube, nasal airways, or a laryngeal mask airway, or face mask -pt hearing is last to go
Halothane/ Fluorthane
Inhalation Agent Volatile liquid used for rapid smooth induction, -Causes bronchodilation, shivering, liver toxicity, -Contraindicated for C-section -d/t smooth muscle relaxation
oropharyngeal airway (OPA)
Inserted I guess to prevent tongue or epiglottis from falling back against pharynx, for pts with respiratory function but need airway support Pts are semi conscious
arterial line
Invasive radial or femoral entry monitors B/P
Pulmonary artery catheter
Invasive right atrium entry monitors cardiac output, PCWP also called Swan-Ganz
esophageal probe
Invasive temperature monitor listen to heart/lung sounds
Endotracheal tube
Invasive airway that extends from the mouth to the trachea, with a rigid laryngoscope
Assistive devices
Laryngoscopes Magill forceps Styles Oral/ nasal airway Nerve stimulator
Inhalation Agents
Oxygen Nitrous Oxide Halothane Enflurane Isoflurane Desflurane Sevoflurane
Preoperative evaluation
Perform assessment to determine pt specific needs and risk factors
General Anesthesia aka
Peripheral nerve block
Shock treatment
Plasma expander Dextran Trendelburg position
Hypnotic drugs
Produce varying levels of hypnosis from light to more natural sleep of sedation to full unconsciousness of General anesthesia
antianxiety drugs
Reduce anxiety, are antiemetic, antihistamine, potentiate anesthesia Ex. Phenergan, Valium, Ativan, versed
Antiemetic drugs
Reduce nausea and vomiting Ex. Reglan, zofran, droperidol
What helps place endotracheal tubes?
Stethoscope
Amnesia permits:
Use of safe, less toxic anesthetic agents and techniques while providing a calm and cooperative patient
sensation
ability to feel stimuli in the environment
Cardiac dysrhythmia
abnormal heart rate or rhythm (atrial or ventricular)
Shock
abnormal physiological state indicated by presence of reduced cardiac output, tachycardia, hypotension, diminished urinary output
analgesia
absence of pain produced by drugs
cyanosis
blue or dusky hue of skin
coma
deepest state of unconsciousness where most brain activity ceases
antagonist
drug that counteracts the effects of another agent or physiological process
sedative
drug that induces a range of unconscious states
agonist
drug that potentiates the release or uptake (or both) of other medications
anxiolytic
drug that reduces anxiety
anesthetic
drug that reduces or blocks sensation or induces unconsciousness
Desflurane/ Suprane
has pungent aroma, has more rapid onset and recovery, safe to use with liver disease
Maintenance agents given
inhalation agents nondepolarizing neuromuscular blocker analgesic/ opiod reversal agents
another name for Spina anesthesia
intrathecal
Malignant Hypothermia more common in
males
Sir Ivan Whiteside Magill
many styles of endotracheal tubes and laryngoscopes are based on his designs
Monitored Anesthesia Care (MAC)
monitoring of vital functions during regional or local anesthetics to ensure the pts safety and comfort
fasciculation
muscle twitching
IV Agents
narcotics/ Analgesic sedatives/ tranquilizers atropine sulfate succinylcholine hydrochloride morphine sulfate alfentanil fentanyl demerol
protective reflexes
nervous system response to harmful environmental stimuli like pain, obstruction of airway, extreme temperature, coughing, blinking, shivering, withdrawal
Stage I: AMNESIA
pt is conscious and with administration (induction) of anesthetic agent moves to loss of consciousness -received propofol, succinylcholine
Enflurane/ Ethrane
rapid induction and recovery, used for maintenance of anesthesia
Isoflurane/ Forane
similar to halothane and enflurane
Allergic reactions
skin irritation or anaphylaxis (immediate hypersensitivity) reaction, can result in life threatening respiratory distress that leads to vascular collapse or shock
homeostasis
state of balance in physiological functions
Goal of surgical anesthesia
to allow the pt to tolerate surgery and maintain the body in a balanced physiological state (homeostasis)
CRNA- Certified Registered Nurse Anesthetist
trained and licensed to administer anesthetic agents
doppler
ultrasonic device assess vascular sounds
General Anesthesia accomplishes:
unconsciousness analgesia amnesia muscle relaxation maintains homeostasis
balanced anesthesia
use of multiple drugs to produce sedation, analgesia, amnesia, and muscle relaxation during general anesthesia
Sevoflurane
used for pediatric anesthesia, rapid induction and recovery
Agent instillation
Administration of mediation's into areas where it can be absorbed such as the rectum, vagina, mucous membranes
Agent injection
Administration of medications directly into the blood stream via IV
Hypnosis
Altered state of consciousness, related to the pt perception of the surgical environment and the surgical procedure
Physical status codes established by
American Society of Anesthesiologists
Preoperative checklist
Chart Identity Correct procedure, site, side Consent forms Resuscitation orders Allergies Preop meds Prostheses & Jewelry removed Medical records Test results CBC Coagulation studies ECG Chest X-ray
Laryngeal airway mask (LMA)
Manages airway without laryngoscope, fits over larynx, used for pts with difficult airway conditions but doesn't protect against aspiration
Nerve blockers/ esters
Tetracaine Pontacaine
Epidural Anesthesia
agent is injected into epidural space, before the Dura, and infuses into spinal cord. Catheter placed and taped to pt back. Lumbar Caudal * commonly used in obstetrics/ C section * slower onset but longer duration and can be titrated
Anticholinergics
Used to block secretions, prevent laryngospasms, prevent reflex Bradycardia ( can cause dry mouth and not for glaucoma pts) Ex. Atropine, robinul
NON-depolarizing muscle relaxant
Used to maintain relaxation during surgical procedures atracurium/ tracrium cisatracurium/ nimbex mivacurium/ mivacron rocuronium/ zemuron vecuronium/ norcuron
Sedative/tranquilizer/ amnesia agents
Versed Valium
Phase 4: Recovery
Vital signs are stable, oxygen needs to be on pt, pt returns to optimum level of consciousness. Usually begins in the OR and follows in PACU. -monitoring is still important -sounds heard
anesthesia
absence of sensory awareness or medially induced unconsciousness
Spinal Anesthesia
agent is injected into subarachnoid space and anesthetizes spinal motor nerve roots, eventually enters bloodstream -fast induction but shorter lived than epidural
Regional Anesthesia
aka Peripheral Nerve Block injection site is proximal to surgical site
Anesthesia technician
allied health professional trained to assist the anesthesia care provider
general anesthesia
alteration in the patients perception of their environment through alterations in their level of consciousness
Sedatives used for
amnesia, hypnotic effects
airway
anatomical passageway or artificial tube through which the pt breathes
topical anesthesia
anesthesia of superficial nerves of skin or mucous membranes
regional block
anesthesia to specific area of body achieved by injection of an anesthetic around a major nerve or group of nerves
Inhalation Anesthesia
anesthetic agents are inhaled and pass to the blood stream through pulmonary function -Non-flammable -rapid acting
Epidural most commonly used for:
anorectal vaginal perineal lower abdomen lower extremities
Treat Cardiac ventricular fibulation/ amides
anti arrhythmic Lidocaine HCL Xylocaine HCL
parasympathetic nervous system (PNS)
part of autonomic nervous system responsible for energy conservation and rest, relaxation of muscle groups, dilation of blood vessels and decreased blood pressure
Stage III: SURGICAL ANESTHESIA
period between onset of regular breathing and loss of eyelid reflex to cessation of breathing. Pt is unresponsive to painful stimuli and sensations, allowing incision to be made and procedure performed without negative response
apnea
period of cessation of breathing
Stage II: EXCITEMENT or DELIRIUM
period of loss of consciousness to return of regular breathing and loss of eyelid reflex. Pt still responding reflexively and unpredictably to certain stimuli; uninhibited movements -may experience vomiting, laryngoscope, hypertension, tachycardia -use Sellick manuever
ventilation
physical act of taking air into the lungs by inflation and releasing CO2 from lungs by deflation
Fight or Flight response (SNS response)
physiological reaction includes diversion of blood to essential organs, increased heart rate and BP
how is patient tested for level of spinal anesthesia
pinpricked
Michael Jackson drug
propofol
Pre-Induction Phase
pt arrives in OR calm and stable, ACP attaches monitoring devices (vital signs, EKG) and pre-oxygenates patient
malignant hypothermia (MH)
rare but life threatening reaction in which an inherited muscle condition causes a hyper-metabolic state in patients exposed to specific trigger agents; experience deficit in calcium transportation within the skeletal muscle fibers
intraoperative awareness (IOA)
rare condition where a pt undergoing general anesthesia is able to feel pain and other stimuli but unable to respond
bier block
regional anesthesia where the anesthetic is injected into a vein
sedation
rousable state in which an individual is unaware of sensory stimuli Depression of the CNS
Laryngospasm/ Bronchospasm
slight trigger of the gag reflex results in spasm or rigidity of the upper respiratory tract; can be triggered by saliva at back of throat, stimulation of lightly anesthetized pt, inflammation from ET tube placement
LMAC
Local Monitored Anesthesia Care
Advantages of Inhalation Anesthesia
-Depth of A can be monitored and rapidly adjusted to alter depth -Gas or vapor is directly exposed to pulmonary circulation allowing for more rapid manifestation
Induction Agents and IV Anesthesia
-combination of drugs used -permits a rapid and pleasant transition from a state of consciousness to unconsciousness -provide sedation and amnesia
Advantages of General Anesthesia
-pt unaware of activities and noises associated with operation -depth and rate of respiration can be controlled & pulmonary tree is usually protected from aspiration (once airway established) -medications can be easily titrated -muscle relaxation for intubation and retraction at the surgical site is easily achieved
Signs of MH
1st unexplained tachycardia followed by tachypnea, increased CO2 levels, unstable BP, perspiration, muscle contraction, cyanosis, mottled skin, increased temperature
role of ST in Circulator role
Assist during intubation (Sellicks manuever) Assist applying monitoring devices Maintain quiet environment Know equipment and use Know where shock cart and emergency supplies are kept Be attentive Help transport and position patient Ask ACP before performing anything on pt, removing instruments (post op)
Monitored Anesthesia Care
Local/ nerve block (light sedation, no intubation/gas) Need 2 RN's Patient is awake (twilight anesthesia) For Extremities
BIS monitor
Bispectral Index System Noninvasive monitors level of consciousness (LOC) and prevent intra-operative awareness, try to keep it under 60
preoperative anesthesia interview
Confirm use/type/amount of prescription drugs, alcohol, tobacco, and illegal drugs Prior surgeries and complications experienced Family history of anesthetic complications Record vital signs Evaluate airway Examine organ systems in question
Sir Ivan Whiteside Magill
Developed and refined techniques of endotracheal intubation (namesake: Magill forceps for anesthesia)
Induction Agents
Diprivan (propofol) Amidate Pentothal Sodium Brevital
Treatment of MH
Discontinue anesthesia administration Turn of inhalation agent Give 100% oxygen Non-triggering agent given (Dantrolene) Chilled saline and ice packed into cavities
Sir Ivan Whiteside Magill
First anesthetist to describe technique of blind nasal intubation
Types of anesthesia
General Nerve Conduction blockade Topical Local Regional
4 Stages of Anesthesia
I- Amnesia II- Excitement or delirium III- Surgical anesthesia IV- Overdose
Oxygen
Inhalation Agent essential for pt, helps to maintain good O2 sats; green tank
Nitrous Oxide
Inhalation Agent laughing gas used adjunct to IV anesthesia; blue tank
General anesthesia accomplished by:
Inhalation agent Injection agent Instillation agent
Reverses Versed or Valium (sedatives)
Mazicon Flumazenil
MAC
Monitored Anesthesia Care
Reverses Opioids & Narcotics (like Demerol)
Narcan Revex
Oxygen delivery by
Nasal cannula, oxygen mask
Types of Regional Anesthesia
Nerve Plexus block Bier block Spinal Block Epidural Anesthesia
Types of Nerve Conduction Blockade agents
Nerve conduction blocking Amino amid group Amino ester group Adjunctive
Muscle relaxation
Neuromuscular blockers in combination with inhalation agents are capable of producing a profound muscle relaxation, permitting tracheal intubation and ability to work in certain areas
Nondepolarizing muscle relaxer
Norcuron Tracrium Pavulon
How to control level of spinal anesthesia
Patient positioning: Lateral Sitting * arch back like "mad cat"
Phases of General Anesthesia
Pre-Induction 1. Induction 2. Maintenance 3. Emergence 4. Recovery
Sedative/ amnesia drugs
Promote sleep and lack of memory Ex. Versed, Valium, ativan
Sedative/ hypnotic drugs
Promote sleep and reduce anxiety, can cause hallucinations Ex. Phenobarbital, ketamine
Sedation/ anesthesia Induction agents
Propofol Diprivan
Nasopharyngeal airway
Provide passageway between nostril and nasopharynx. Pts are semiconscious, gagging, or mouth injury present
Advantages of Spinal
Pt awake so control airway Non-irritating to respiratory tract Blockade of PNS and SNS Produces bowel contractions Facilitates abdominal exposure produces excellent muscle relaxant
halogenated
The danger of fire in the OR has been reduced with the introduction of which kind of anesthetics?
Agents that reduce secretions, treat bradycardia
anticholinergic Atropine Robinul
Phase 2: Maintenance
begins after insertion of airway and continues through surgical intervention until end of operation -pt monitoring is critical -surgical interventions can change pt status
Preoperative agents given
benzodiazepines (sedation and amnesia) anticholinergic (inhibit secretions, increase heart rate) antacids antiemetics
gas scavenging
capture and safe removal of extraneous anesthetic gases from the machine
Cardiac arrest
cessation of heart pumping action and blood circulation
Horace Wells
dentist that used nitrous oxide for teeth
Induction agents given
depolarizing muscle relaxant hypnotics
sedatives (agents)
diazepam/ valium midazolam/ Versed ketamine/ ketalar
cricoid pressure
direct manual pressure on the cricoid cartilage to prevent aspiration and facilitate intubation -Also called "Sellick Maneuver"
Reversal NeuroMuscular blocking agents
edorphonium neostigmine
Phase 3: Emergence
end of surgical procedure anesthetic gases are discontinued and allowed to wear off. Process of regaining consciousness. -pt begins breathing on own, ET tube extubated, start hearing again
James Simpson
introduced chloroform to anesthesia
bronchospasm
involuntary smooth muscle spasm of bronchi
John Snow
first anesthetist
Crawford Long
first to use ether during a surgical procedure (tumor removal) 1842
infusion
giving a drug over a specified period
Aspiration
greatest during induction and emergence phase leading to aspiration pneumonia -use Cricoid pressure (Sellick Manuever) to prevent
Nerve Conduction Blocks
involves use of pharmaceutical agents to prepare the transmission of sensory nerve impulses
amnesia
lack of recall of events or sensations
regional anesthesia agent chosen by:
length of procedure level of block needed pt condition and health
Stage IV: OVERDOSE
level of anesthesia so deep that cardiovascular and respiratory function is compromised to the point of collapse due to depression of those centers in the brain -characterized by dilated or nonreactive pupils and major drop in BP -experience shock, neurological issues - if uncorrected this stage will lead to pt death
ACP- Anesthesia Care Provider
licensed to administer anesthetic agents, manage the pt through out anesthesia, & respond to anesthetic and surgical emergencies
anaphylaxis
life threatening allergic reaction to a drug or substance
unconsciousness
neurological state where one is unable to respond to external stimuli
consciousness
neurological status in which a pt is able to SENSE environmental stimuli (touch, sound, pain, pressure, heat, cold)
nerve stimulator
noninvasive assesses muscle relaxer effectiveness
EKG/ECG
noninvasive detects arrhythmia AKA electrocardiogram
capnography
noninvasive measures end-tidal CO2 levels
pulse oximetry
noninvasive monitors oxygen level
spirometry
noninvasive monitors ventilation volume, pressure
pulmonary embolism (PE)
obstruction in a pulmonary vessel by a blood clot, air bubble, or foreign body causing sudden pain or possible pulmonary arrest
Sympathetic Nervous System (SNS)
part of autonomic nervous system responsible for Fight or Flight response to danger or stress
Disadvantages of Spinal Anesthesia
spinal headache hypotension parasthesia/ paralysis (temporary)
hypothermia
subnormal temperature
depolarizing muscle relaxant
succinylcholine, anectine, quelicin -can cause fasciculations, temporary paralysis, MH
Stages of Anesthesia
the patient passes through stages from consciousness to deep surgical anesthesia. They are based on physiological effects (body movement, respiratory rhythm, oculomotor reflexes, muscle tone)
Nerve block agents
xylocaine/ lidocaine carbocaine/ mepivacaine marcaine/ sensorcaine duranest/ etidocaine pontocaine/ cetacaine