 VET 212 Anesthesia Study Guide (Answered) Complete Solution

 VET 212 Anesthesia Study Guide (Answered) Complete Solution Chapter 1 1)List 2 North American professional organizations that offer specialization in anesthesia and analgesia to credentialed individuals, and summarize the aims of each ACADEMY of VETERINARY TECHNICIANS IN ANESTHESIA and ANALGESIA (AVTAA) --> promotes patient safety, consumer protection, professionalism and excellence in anesthesia care AMERICAN COLLEGE of VETERINARY ANESTHESIA and ANALGESIA (ACVAA) --> 2)Define anesthesia, and differentiate topical, local, regional, general, and surgical anesthesia TOPICAL ANESTHESIA→loss of sensation of a localized area produced by administration of a local anesthetic directly to a body surface or surgical or traumatic wound (small areas) LOCAL ANESTHESIA→ loss of sensation in a small area of the body produced by administration of a local anesthetic agent in proximity to the area of interest (small areas) REGIONAL ANESTHESIA→ loss of sensation in a limited area of the body produced by administration of a local anesthetic or other agent in proximity to sensory nerves (nerve blocks, epidural anesthesia, large areas) GENERAL ANESTHESIA→reversible state of unconsciousness, immobility, muscle relaxation, and loss of sensation throughout the entire body produced by one or more anesthetic agents SURGICAL ANESTHESIA→ specific state of general anesthesia in which there is a sufficient degree of analgesia (loss of sensitivity to pain) and muscle relaxation to allow surgery to be performed without patient pain or movement 3)Differentiate sedation, tranquilization, hypnosis, and narcosis SEDATION→ drug induced CNS depression and drowsiness that vary in intensity from light to deep TRANQUILIZATION→ drug induced state of calm in which the patient is reluctant to move and is aware of but unconcerned about its surroundings HYPNOSIS→ drug induced sleep like state that impairs the ability of the patient to respond appropriately to stimuli---sleep like state from which the patient can be aroused with sufficient stimulation NARCOSIS→ drug induced sleep, the patient is not easily aroused, most often associated with administration of narcotics 4)Explain the concept of balanced anesthesia and the advantages of this approach Balanced anesthesia (the administration of multiple drugs to the same patient during one anesthetic event) maximizes benefits, minimizes adverse effects, and gives the anesthetist the ability to produce anesthesia with the degree of CNS depression, muscle relaxation, analgesia, and immobilization appropriate for the patient and the procedure Example: premedication, then maintenance with inhalant, the post op medication for analgesia 5)List common indications for anesthesia GENERAL ANESTHESIA→ most common, fully immobilizes the patient, procedures can be performed quickly and safely, inexpensive, uses balanced techniques SEDATION→ can be mild or heavy, neuroleptanalgesia, used for minor procedures, diagnostics, physical examination 6)Describe fundamental challenges and risks associated with anesthesia -most anesthetic agents have a narrow therapeutic index so care and attention to detail are critical when dosages are calculated and rates are adjusted -most anesthetic agents cause significant changes in cardiovascular and pulmonary function and can be dangerous or fatal--vital signs must be closely monitored -the potential for patient harm during administration of anesthetics is relatively high -must keep detailed and accurate anesthetic records 7)List the qualities and abilities of a successful veterinary anesthetist -the anesthetist must accurately interpret a wide spectrum of visual, tactile, and auditory information -the anesthetist must have a comprehensive understanding of the significance of physical parameters and machine generated data Chapter 2 1)Explain the importance of effective communication and the role of the veterinary technician in communication. -veterinarians depend on accurate information at all stages of the procedure to make effective patient care decisions -clients need clear instructions and answers to questions before the procedure, progress reports, and home care instructions afterwards -the technician acts as a liaison between the dr and the client 2)List the reasons for preoperative patient evaluation. -to uncover hidden problems that may increase risk or alter patient management 3)List the parts of a minimum patient database. -used to make patient care decisions -patient history, including the patient signalment -complete physical examination findings -results of a preanesthetic diagnostic workup 4)Take a complete history, and identify findings that affect anesthetic event planning. -when taking a history emphasize open-ended questions, avoid leading questions or questions that can be answered yes or no -gather signalment, current and past diseases, medications, allergies, statues of preventative care -when gathering historical information about signs of illness always ask the following: -the duration (how long has it been going?) -the volume or severity (how much or how severe?) -the frequency (how often?) -the character or appearance (what does it look like?) 5)Identify ways in which patient signalment influences the anesthetic procedure and patient management. SPECIES→ each species has unique responses to anesthetic agents and unique needs associated with anesthesia...horses and cats are more sensitive to opioids, horses have rougher recoveries, ruminants are prone to bloat BREED→ differences in anatomy and physiology among various breeds may affect an animal’s response to anesthetic agents...brachycephalic animals are difficult to intubate, sighthounds are sensitive to barbiturates, draft horses are sensitive to sedatives AGE→ determines what drugs to use...neonates and pediatric patients are less able to metabolize injectable drugs SEX and REPRODUCTIVE STATUS→animals in heat make a spay more difficult, ace is contradicted in stallions 6)Discuss the rationale for obtaining the owner’s consent for anesthesia. -it is illegal in more jurisdictions to undertake surgery or anesthesia on an animal without an owner’s written or oral consent -the owner is warned beforehand of risks associated with the procedure -the owner gets a written estimate of the expected charges and obtain a signed consent form authorizing anesthesia and surgery 7)Perform a preanesthetic physical assessment. PATIENT IDENTIFICATION→ identification collars must be placed on all patients. Proper patient identification is essential, ensure correct surgery if being performed on the correct area BODY WEIGHT→ all animals must be accurately weighed immediately before any anesthetic procedure BODY CONDITION SCORE→ can range from 1-5 or 1-9, with 1 being emaciated and 9 being grossly obese, helps assess overall wellbeing of the patient as well as drug calculation (drug calculation based on lean body weight) ASSESSMENT OF HYDRATION→ dehydrated patients may need to be stabilized prior to anesthetic induction, look at MM, tent the skin, look at the eyes LEVEL OF CONSCIOUSNESS→ BAR, QAR, Lethargic, obtunded, comatose, decreased level of consciousness indicates abnormal brain function PAIN SCORE→ BODY TEMPERATURE→ 8)Relate the patient signalment, body weight, and patient condition to the selection and use of anesthetic agents and adjuncts. PATIENT SIGNALMENT→ breed, sex, age, species BODY WEIGHT→ BCS, is the patient emaciated or obese PATIENT CONDITION→ health status, are there pre existing conditions 9)Assign a patient to one of the five physical status classifications as specified by the American Society of Anesthesiologists. PS1/ ASA I→ minimal risk, normal healthy patient, patients undergoing elective procedures (spay, neuter) PS2/ ASA II→ low risk, patient with mild systemic disease, neonatal, geriatric, or obese patients, mild dehydration, skin tumor removal PS3/ ASA III→ moderate risk, patients with severe systemic disease, anemia, moderate dehydration PS4/ ASA IV→ high risk, patients with severe systemic disease that is a constant threat to life, ruptured bladder, internal hemorrhage, pyometra PS5/ ASA V→ extreme risk, patients that are not expected to survive without the operation, severe head trauma, pulmonary embolism, end stage major organ failure E→ emergency 10)Describe the components of preanesthetic preparation, including diagnostic testing, choice of protocol, withholding of food, and correction of preexisting problems. PREANESTHETIC PREPARATION→ ensure that the patient has been properly fasted, complete PE performed and pet is auscultated DIAGNOSTIC TESTING→ radiographs, echocardiogram, CBC, chemistry, PCV, urinalysis CHOICE OF PROTOCOL→ facilities and equipment, familiarity with the agent, nature of the procedure, circumstances specific to the procedure, cost, degree of urgency WITHHOLDING FOOD→ animals that aren't fasted are prone to reflux of the stomach contents into the distal esophagus, aspiration into the pulmonary tree, and bloating in ruminants, dogs and cats are prone to vomiting after premedications CORRECTION OF PREEXISTING PROBLEMS→ dehydration 11)List the reasons why an intravenous (IV) catheter is advisable for anesthetized patients. -fluid administration helps to maintain blood volume and support blood pressure -IV access allows rapid administration of emergency drugs such as epinephrine -an IV catheter can be used for CRI of anesthetics, analgesics, electrolytes, or other drugs -vesiants can be administered -incompatible drugs can be administered more easily 12)Describe the types of IV fluids that are used during anesthesia and why each might be chosen. -electrolytes are essential for several fundamental physiologic processes (heart function, blood clotting, neuromuscular function) -solutes such as protein participate in regulation of blood pressure, blood clotting, drug transport -homeostasis -why give IV fluids: anesthetic drugs cause vasoconstriction which leads to hypotension, bleeding, open body cavity leads to fluid loss NORMAL SALINE→ used to bathe exposed tissues during surgery, flush IV catheters, flush body cavities, used in patients with brain disease, blood transfusions COLLOID SOLUTIONS→ used to support expansion of blood volume and blood pressure (hetastarch, blood products) ideal for bolusing CRYSTALLOIDS→ maintains hydration in healthy patients 13)Calculate IV fluid infusion rates. INFUSION RATE→ mL/hr, programs the IV pump DRIP RATE→ gtt/min, value used to adjust the administration set *use the patient's weight and the prescribed rate to calculate the infusion rate in mL/hr *using the infusion rate, the delivery rate, and conversion factors, calculate the drip rate in gtt/min * rate is going to depend on patients health status *determine the body weight, determine prescribed weight, calculate infusion rate Weight (kgs) x rate (ml/kg/hr) = mls/hr To calculate drip rate: Infusion rate (ml/hr) x time conversion (hr/min) x delivery rate (gtt/ml) = gtt/min Divide by 60 to get gtt/sec Chapter 3 1)Classify anesthetic agents and adjuncts based on route of administration, time of administration, principal effect, or chemistry. ROUTE OF ADMINISTRATION→ inhalants, injectables BASED ON THE TIME PERIOD AT WHICH THEY ARE GIVEN → preanesthetic medications, Induction agents, maintenance agents PRINCIPAL EFFECT→ local anesthetics, general anesthetics, neuromuscular blockers, reversal agents CHEMISTRY→ ANESTHETIC DRUG PROPERTIES→ produce reliable sedation and anxiolysis, have minimal effects on the CV system, cause minimal respiratory depression, produce analgesia, ability to reverse if necessary, affordable HOW TO CHOOSE THE RIGHT DRUG→ ASA rating, species and breed, temperament, age, reason for anesthesia and procedure performed, degree of pain expected from the procedure 2)Differentiate agonists, partial agonists, agonists–antagonists, and antagonists based on their action and effect. List anesthetics and adjuncts that can be reversed. AGONISTS→ bind to and stimulate tissue receptors--most anesthetics and adjuncts PARTIAL AGONISTS→ bind to and partially stimulate receptors AGONISTS-ANTAGONISTS→ bind to more than one receptor type and simultaneously stimulate at least one and block at least one ANTAGONISTS→ bind to but do not stimulate receptors--given after an agonist 3)Apply principles of safe administration of anesthetic agents and adjuncts. 4)List anesthetic agents and adjuncts commonly used as preanesthetic medications, and describe their indications, mode of action, effects, adverse effects, and use ANTICHOLINERGICS→ prevent and treat bradycardia and decrease salivary secretions, parasympathetic effects, adverse effects: mydriasis, tachycardia, reduction of GI tract and lacrimal secretions (atropine) PHENOTHIAZINES→ acepromazine, calming, antipsychotic, mood altering effects, no analgesia, antiarrhythmic properties, vasodilation, does not work well in cats and boxers and giant breeds are sensitive, great for sedation, not reversible BENZODIAZEPINES→ diazepam, midazolam, sedative, reduces anxiety, best with pediatric or geriatric patients, and best when combined with opioids, reversible, used for seizure control, excellent muscle relaxation ALPHA2-AGONISTS→ dex, potent sedative, some analgesic properties, reversible, reduces anesthetic induction and inhalant requirements, reduces cardiac output, safe in young and healthy animals, not for sick or geriatric OPIOIDS→ used for analgesia, sedation, and anesthetic induction, produces respiratory depression, improves sedation when combined with tranquilizer or sedative (neuroleptanalgesia) 5)List injectable anesthetic drugs in common use, and describe their indications, mode of action, effects, adverse effects, and use. PROPOFOL→ ultrashort acting nonbarbiturate with wide margin of safety, rapid onset, muscle relaxation, antiemetic effect, bradycardia ETOMIDATE→ used for induction of anesthesia, hypnosis with minimal analgesia, anticonvulsant effect, muscle relaxation, nausea, vomiting, excitement ALFAXALONE→ CNS depression, minimal cardiovascular depression, tachycardia, hypotension, hypnosis, muscle relaxation, apnea, heavy sedation after IM injection, KETAMINE→ analgesia, amnesia, maintains ocular, laryngeal, pharyngeal, and pedal reflexes, rapid onset, dose dependant CNS depression, cannot be used to cats with renal disease, stimulate CV systems, increases ICP and IOP, should not be used in patients with seizure disorders or brain disease 6)Describe the effect of protein binding, lipid solubility, and redistribution on the pharmacokinetics and pharmacodynamics of injectable anesthetics. PROTEIN BINDING→ bound to protein and unable to penetrate cell membranes LIPID SOLUBILITY→ the tendency of a drug to dissolve in fats, oils, or lipids, related to the ability to penetrate the fatty layer of cell membranes REDISTRIBUTION→ the way in which a drug is distributed to various tissues based on blood flow **propofol= bound to protein and enters the brain to induce anesthesia, it has a high lipid solubility and is rapidly removed from the brain by tissue redistribution and is eliminated by the body 7)Define dissociative anesthesia; describe the actions and effects of dissociative anesthetics, and explain ways in which these drugs differ from other injectable anesthetics. -used in cats for minor procedures -commonly used in combination with a variety of tranquilizers and opioids to induce general anesthesia -cataleptic state, intact reflexes, eyes open, pupils central and dilated, normal or increased muscle tone, analgesia, sensitivity to sound, light, or other sensory stimuli, nystagmus -ketamine, guaifenesin 8)List the inhalation anesthetic agents in common use, and describe their indications, mode of action, effects, adverse effects, and use. -dose-related CNS depression, hypothermia, paddling, excitement, vasodilation, decreased cardiac output, muscle relaxation, hypoventilation, quick changes in anesthetic depth