ECP 3 Flashcards

Question

Acute resuscitative fluid therapy intraoesseous catheter when used

Answer 1

- Routinely in very small patients (kittens and puppies) - In adult patients where IV access fails - Cardiopulmonary arrest

Answer 2

1. Isotonic crystalloid fluids 2. Synthetic colloids 3. Hypertonic saline 4. Blood products: ○ Whole blood ○ Packed red blood cells ○ Fresh frozen plasma

Answer 3

- Tonicity >> ECF -> fluid from interstitial space to intravascular space - Indications: ○ Rapid volume expansions ○ Large dogs - GDV ○ Head trauma (may decrease ICP) - Combination with colloids -> water clings to colloid so contain water within vascular - provides prolonged affect

Answer 4

``` - Other effects: ○ Decrease intracranial pressure ○ Reduce endothelial swelling ○ Decrease leucocyte adhesion ○ Increase cardiac contractility ○ Milkd peripheral vasodilation - Contraindications ○ Dehydration ○ Normovolaemia/hypercolaemia ○ Hypernatraemia -> adding to the imbalance of sodium ○ Inability to handle sodium load (renal disease) ```

Answer 5

- Dog: Up to 20ml/kg total/day - Cat: Up to 10ml/kg total/day - Small volume resuscitation -> if give large volumes and increase vascular permeability movement of colloid into interstitium and moves water into interstitium resulting in loss of water instead of gain in intravascular system - Adverse effects ○ Coagulation impairment -> covers platelets so platelet activation is impaired ○ Renal failure in people, in dogs?

Answer 6

- Increase PCV and O2 transport capacity - For acute haemorrhage ○ Replace what is lost (estimate) ○ Target PCV > 20% - To increase PCV by 1% ○ Packed red blood cells: 1ml/kg ○ Whole blood: 2ml/kg - Cats: always blood type

Answer 7

1. Species 2. Severity of hypoperfusion 3. Presence of risk factors 4. Type of fluid used 5. Response of patient

Answer 8

- Dogs: -90ml/kg | - Cats: -50-60ml/kg

Answer 9

- Resuscitation endpoints -> what is your endpoint, what is your heart rate target, mentation etc. (measured) - You may also stop if you hit a safety endpoints (measured) -> crackles in lungs etc Assessment of sock -> fluid aliquot -> assessment of shock -> fluid aliquot (adjust if needed) -> assessment of shock etc until NO SHOCK

Answer 10

- Higher body weight more variance in fluid therapy totals depending on formula -> need to be careful with horses

Answer 11

- According to Poiseuille's law an increase in the radius by 2times will increase the flow rate by 16 times ○ In larger animals need to use a larger radius for more flow

Answer 12

- Balanced fluid therapy: isotonic to plasma and electrolytes similar ○ Lactated ringers solution - balanced ○ Normal saline - not-balanced

Answer 13

600mOsm/L ○ Due to damage to vessels leading to phlebitis ○ If need to give more administer via central veins

Answer 14

PCV = manual measurement | Haematocrit HCT = RBC count x RBC volume

Answer 15

MCV - mean corpuscular volume = average size MCH - mean corpuscular haemoglobin = total Hb per cell - less accurate MCHC - mean corpuscular haemoglobin concentration = concentration of Hb in each cell - more accurate RDW - red cell distribution width (measure of anisocytosis/size variation) - If large size variation and low MCV generally due to lower average size RBCs etc. ○ Best way to check is via the smear NRBC - nucleated red blood cells

Answer 16

1. Regenerative or non-regenerative anaemia ○ Loss (haemorrhage, haemolysis) - regenerative -> reticulocytes or polychromatophils present ○ Decreased production - non-regenerative 2. Is the protein level low, normal or high ○ If haemorrhaging red cells and plasma lost -> losing protein so low protein ○ Haemolysis -> only destroying RBCS -> normal protein ○ Internal haemorrhage -> protein level can be close to normal as reabsorbed 3. Are there clues on the blood film ○ Oxidative damage, sheer injury -> haemolysis ○ Haemangiosarcoma

Answer 17

1. Regenerative = elevated reticulocyte count ○ Increased RBC loss - haemorrhage or haemolysis 2. Non-regenerative = normal or low reticulocyte count ○ Reduced rbc production - chronic disease/inflammation, marrow disease, iron deficiency 3. Pre-regenerative = too soon since RBC loss for an apparent marrow response to be evident in the blood

Answer 18

1. Is there evidence of an inflammatory response? ○ Neutrophilia and/or monocytosis ○ Left shift (bands) or toxic change -> ALWAYS INFLAMMATORY 2. Is there evidence of stress response? ○ Lymphopenia (most consistent finding) ○ +/- mature neutrophilia ○ +/- monocytosis (dogs) 3. Is there a physiologic leucocytosis? ○ Mature neutrophilia and lymphocytosis in young animal

Answer 19

``` Loss via 1. Consumption 2. Destruction 3. Sequestration 4. Haemo-dilution Increase via 1. Production 2. Absorption 3. Haemo-concentrations ```

Answer 20

- Increase in either or both = azotaemia -> pre-renal, renal, post-renal

Answer 21

○ Decrease renal blood flow -> Decrease Glomerular filtration rate ○ Causes § Dehydration -> concentrated urine □ Greater increase in urea than creatinine □ Clinical evidence -> skin tenting, capillary refill time § GIT protein absorption or bleeding Increased urea only unless co-current dehydration

Answer 22

○ Decrease functional nephrons -> Decrease glomerular filtration rate ○ Poorly concentrated urine despite dehydration (in context of how dehydrated they are) ○ Causes 1) Acute renal insufficiency □ Acute history □ Hyperkalaemia □ Oliguria or anuria (present like post-renal azotaemia) 2) Chronic renal insufficiency □ Chronic history - weight loss □ Often anaemic □ Polyuria -> hypokalaemia as losing potassium and stops eating as much

Answer 23

○ Decrease in urine output ○ Generally diagnosed based on clinical findings - stranguria, haemuria ○ Causes § Urinary obstruction § Uroabdomen § Hyperkalaemia - good clue § Variable USG depending on hydration status

Answer 24

metabolic disease resulting in decreased kidney response - Medullary hypotonicity or impaired ADH can mimic renal failure ○ Hypochloridemia ○ Hypoadrenocorticism ○ Hyperadrenocorticisim ○ Diabetes insipidus -> can't respond to ADH ○ Pyometron - E.coli toxin stops ADH

Answer 25

- Clinical signs - decreased skin turgor, tacky membranes - CBC or biochemistry ○ Increase Hct/RBC/Hb (masked by blood loss) ○ Increase albumin (masked by protein loss) ○ Increase Na and Cl (masked by electrolyte loss) ○ Urea with normal creatinine

Answer 26

- Urea synthesise - Cholesterol synthesise -> cholesterol can go high with cholestasis (so can be normal if liver disease makes decrease and cholestasis makes increase) - Albumin synthesise - Glucose synthesise - Bilirubin conjugation - Bile acids uptake and excretion - Ammonia uptake and metabolism

Answer 27

``` Enzymes that reflect liver damage (leakage) - ALT (muscle) - GLDH - AST (muscle, rbc) - LDH (muscle, rbc) - SDH Enzyme that reflects cholestasis or induction - ALP - Corticosteroid ALP in dogs - GGT ```

Answer 28

1. Is there evidence of cell damage? ○ Increased ALT, AST, GLDH, SDH 2. Is there evidence of cholestasis? ○ Increased bilirubin, ALP, GGT 3. Is there evidence of hepatic insufficiency? ○ Decreased urea, cholesterol, albumin, glucose ○ Increased unconjugated bilirubin

Answer 29

1) Amylase 2) lipase Not as sensitive - 70% of dogs with not have an increase in amylase and lipase with pancreatitis Remember: amylase and lipase undergo renal excretion -> so can be high with renal disease and decreased glomerular filtration rate Other findings with pancreatitis - Inflammatory leukogram - Lipaemia - Hyperglycaemia

Answer 30

1) CK 2) AST - also haemolysis and liver damage Urine -> Myoglobin -> looks like haemoglobinuria on dipstick as cross-react

Answer 31

Total protein = albumin + globulins Level depends on: - Colostrum absorption in neonates - Synthesise (liver function, inflammation, immunocompetence) - Hydration status - Loss (renal, GIT, third space, exudation)

Answer 32

- to calm the patient - removing stress from animal and people -> decrease negative experiences - to provide peri-operative analgesia - to reduce the total amount of anaesthetic - decrease drug concentrations needed to maintain anaesthesia - to reduce nausea and vomiting -> important with opioids - to smoothen recovery -> relying on the drugs given during premedication still being in the system - To reduce autonomic side-effects

Answer 33

1. animal temperament - alpha2-adrenoceptor agonist + opioid - more aggressive animals ○ phenothiazine + opioid - more relaxed 2. duration of procedure ○ antagonism may be desirable -> if short procedure with longer lasting drugs 3. health status of patient ○ cardiovascular disease / hypovolaemia 4. availability of drugs 5. personal preference

Answer 34

Most commonly - Tranquilizer/sedative agent + opioid Why - synergistic effects - produces reliable “safe” sedation - reduces dose of induction and maintenance agent -> reduce the side-effects - pre-emptive analgesia

Answer 35

``` What can we use for sedation? 1. Phenothiazine ○ Acepromazine - preferred 2. Alpha2-adrenoceptor agonist ○ Xylazine, (dex)medetomidine, romifidine, detomidine 3. Benzodiazepine ○ Diazepam, midazolam ```

Answer 36

Sedation in premedication Main effects: - Tranquillization -> good for horses!!!! - anti-arrhythmic -> decrease sensitivity of myocardium to catecholamines - anti-emetic - spasmolytic - Antihistamine -> effect the skin test for allergic reactions - don't use when doing this - Alpha1 receptor blockade (antagonist)

Answer 37

Sedative in premedication - hypotension - care with hypovolaemic patients! -> vasodilation - pink mucous membranes, fast capillary refill time (MAIN DIFFERENCE WITH ALPHA-2 AGONISTS) - collapse in some families of Boxers -> UK breed for high vagal tone, blood pressure decrease (vasodilation) and heart rate cannot increase - decrease seizure threshold - don't use in patient with history of seizures - Hypothermia - due to vasodilation

Answer 38

There is probably no good reason for ever giving a patient acepromazine on its own! - not high enough sedation without seeing side effects

Answer 39

``` Sedative during premedication - Widespread distribution throughout the body ○ sympathetic nervous system - most important ○ vascular endothelium - most important ○ CNS (spinal and supra-spinal) ○ platelets ○ uterus ○ Gut ```

Answer 40

1) dose-dependent sedation (way stronger than ACE) / hypnosis 2) Analgesia (very good) 3) Muscle relaxation (very good) 4) respiratory depression (mild) 5) initial period of hypertension, followed by a more prolonged normotensive (?) phase ○ Reflex bradycardia 6) cardiac arrhythmias (where A-V blocks 1 and 2) -> no ventricular complex

Answer 41

Phase one: - Initial increase (hypertension) in blood pressure (peripheric origin) with reflex bradycardia Phase two: - Decrease in blood pressure (back to normal or below) due to centrally mediated decreased sympathetic tone. - Bradycardia is maintained (main problem)

Answer 42

NO - leads to severe hypertension | - If worried give an antagonist however generally doesn't work too well

Answer 43

- Hyperglycaemia - very common - diuresis (problem in horses?) -> if recovering in the box, increase in urination leads to slipping hazard, make sure pee before the box - decreased intestinal motility - Vomiting (mainly xylazine in SA)

Answer 44

Alpha2-agonist used for premedication - extreme care when used as premed high side effects sensitize myocardium to catecholamine emesis (higher than others)

Answer 45

Alpha2-agonist used for premedication more specific less unwanted side effects - use higher dose in cats prior to ketamine

Answer 46

``` Alpha2-agonist used for premedication - Possibly α2 antagonistic properties - Drug interaction - High α1 affinity ○ Anti-sedative effect ○ Myometrial activity ○ Arrhythmias ```

Answer 47

- Only one licensed is atipamezole (“Antisedan”) - will reverse xylazine, medetomidine and dexmedetomidine (tho’ only licensed for last 2 and only in dogs for dexmedetomidine) - will not fully reverse CV depression but worth a try

Answer 48

``` Premedication (sedative Two agents in this class: 1. diazepam (“Valium”; “Diazemul”) 2. midazolam (“Hypnovel”) NOT LICENSED IN ANIMALS! Main effects of benzodiazepines 1. muscle relaxation - good 2. anxiolytic 3. appetite stimulation - used for this 4. minimal cardiovascular and respiratory effects 5. anti-convulsant 6. potential for complete reversal (flumazenil) 7. anti-arrhythmic ```

Answer 49

1. to increase muscle relaxation during anaesthesia 2. to offset muscle hypertonicity caused by ketamine (ketamine creates muscle spasm so decrease this) 3. to stimulate appetite in anorexic patients 4. treatment of seizures 5. to decrease dose of induction agent

Answer 50

The benzodiazepines are excellent agents for sedation in the “poor risk” patient, either alone or in combination with opioid drugs. - Cardiovascular or respiratory compromise -> SICK GOOD DRUG The benzodiazepines are unreliable agents for sedation in the “healthy adult” patient - Due to anxiolytic properties -> brain unreliable, may have sedation and may not

Answer 51

Benzodiazepines - premedication - thrombophlebitis may be seen with “Valium” - inflammatory action - high oral bioavailability

Answer 52

- Act on specific opioid receptors in CNS ○ μ (mu) (OP3 - used in some literature) ○ κ (kappa) (OP2) ○ δ (delta) (OP1) - Brain, spine and periphery

Answer 53

1) Full (pure μ) agonists - BEST ○ morphine, methadone, meperidine, hydromorphone, fentanyl, alfentanil, remifentanil 2) Partial μ agonists - UNRELIABLE - need to give 2 doses, one before and one afterwards ○ buprenorphine 3) κ agonist – μ antagonists - excellent for sedation but poor analgesia (EXCEPT IN REPTILES) ○ butorphanol, nalbuphine

Answer 54

○ are reliable analgesics, and can be titrated to effect ○ best choice for severe pain ○ can be topped up - but the more you give the more side affects you may see

Answer 55

1. CNS - Depression vs excitation (horses, cats? - need to use less) 2. CVS- Minimal effects ○ Possible sinus bradycardia (vagal centre) - usually the blood pressure is maintained 3. Respiratory system ○ Depression ○ Drug and dose-dependent Others… 1. Histamine release (pethidine - DON'T GIVE IV, morphine) 2. GIT depression 3. Release of ADH (urine retention) 4. Hypothermia (but sometimes hyperthermia in cats, horses, swine.....CNS excitation? ) 5. Emesis (chemoreceptor trigger zone) 6. Pupillary diameter (miosis in dog; midriasis in cat) - dog has O - miosis etc. -> if working in eye don't give - IMPORTANT

Answer 56

1) morphine - gold standard, may cause vomiting, - duration of 4 hrs (dog) & 6-8 hrs (cat) 2) Methadone hydrochloride - like morphine but no vomiting 3) hydromorphone - 8x stronger than morphine, emesis less likely, no histamine release 4) Fentanyl and Alfentanil - 100 (fent) or 50 (alfen) x morphone, short acting, severe pain good but bradycardia and respiratory depression common

Answer 57

1. Buprenorphine - partial - Duration 4-6 hours in dogs and 6-8 in cats - Onset of action 30 to 60 min after IM injection 1. Butorphanol - agonist-antagonist - good sedative but ? analgesic efficacy ○ Good anaesthesia for reptiles and birds - probably relatively short-duration (1hr)

Answer 58

1. Pre-existing respiratory depression 2. Head trauma - increase CO2 due to respiratory depression which increases intracranial pressure 3. Pancreatitis - unsure

Answer 59

Most common - induce with intravenous, maintain with inhalant Total intravenous anaesthesia - induce with intravenous, maintain with intravenous Other less common - induce with Inhalant, maintain with inhalant

Answer 60

``` NOT COMMON 1) Chamber induction ○ Don't have much control ○ Box full of gas when remove patient will be exposed to the gas 2) Mask induction Mainly for neonates and puppies ```

Answer 61

the plasma concentration decreases rapidly as a result of both distribution (most important) out of the vascular space and elimination. - Recovery depends upon distribution and elimination half-lives

Answer 62

1. Anesthetic used ○ Lipid solubility - increase anaesthesia ○ Molecular size - decrease increase anaesthesia ○ Protein Binding - only unbound into the brain ○ Ionization - ionised will not cross BBB 2. Dose -> higher faster an aesthesia but more side effects - TITRATE TO EFFECT 3. Rate of administration -> same as above 4. Route of administration -> IV faster than IM (Propofol IM doesn't work) 5. Animals level of consciousness 6. Acid-base, electrolyte and serum protein status 7. Animals cardiac output - higher CO quicker induced - OPPOSITE TO INHALANT

Answer 63

Intravenous agents 1. Barbiturates (thiopental,…) 2. Dissociative agents (ketamine,…) 3. Imidazole derivative (etomidate) 4. Steroids (alfaxolone) 5. Phenol derivatives (propofol)

Answer 64

1) Phenobarital - 12 mins 2) Pentobarbital - 30-60 seconds 3) Thiopental - 15-30 seconds

Answer 65

CNS effects - Depression - GABA receptors - NO analgesia (anti-analgesic at sub-hypnotic doses) Respiratory effects - post-induction apnoea common, especially following opioid premedication. - decreased ventilatory rate and tidal volume, offset to some extent by surgical stimulation

Answer 66

CV effects - Usually increase in heart rate - Decrease in arterial blood pressure ○ more marked in hypovolaemic patients, or following excessive doses ○ decrease peripheral resistance, decrease stroke volume and myocardial contractility - Increased sensitivity of myocardium to circulating catecholamine (arrhythmias common at induction especially in highly stressed animals)

Answer 67

Barbiturate - Induction agent (after premedication) 0 have to give a bolus cannot titrate -> as moves into stage 2 anaesthesia (excitation) - Induction and arousal from anesthesia depends largely on redistribution not from metabolism - Hepatic metabolism 5% total dose is metabolised per hour - recover via redistribution

Answer 68

1) IV only!!!! ○ Skin slough - treatment saline and lidocaine 2) Thin dogs - main way to wake up is redistribution into fat, less fat -> less redistribution -> longer recovery 3) Hypovolaemia 4) Liver dysfunction - due to liver metabolism 5) Age - again metabolism is an issue 6)Obesity - calculate the dose without the fat content as redistribution will occur, overdose is common

Answer 69

``` Cataleptic state • CNS excitation - high brain activity • Analgesia • Immobility - Dissociation from one’s environment • Amnesia Drugs • Ketamine Tiletamine (Telazol) - mixed drug ```

Answer 70

- acidic pH (3.5) -> usually used in combination with other drugs as PAINFUL if give first - produces a state of “dissociative anaesthesia”. - Popular in horses

Answer 71

CNS stimulation - Increase ICP (intracranial pressure) - if use muscle relaxation may decrease - Might cause seizure in dogs and cats - history of seizures DON'T USE - Analgesia somatic > visceral - NMDA antagonist (chronic pain) - Hallucinations/delirium in recovery

Answer 72

Boost cardiovascular system - increased sympathetic tone in vivo. - increased heart rate and contractility. - increased cardiac output and arterial blood pressure. - increased myocardial oxygen demands. Adrenergic system must be intact - if in overdrive then will not lead to boost but depression - NOT USED IN VERY SICK AND DEPRESSED PATIENTS CARDIOVASCULARLY

Answer 73

- transient apnoea possible with IV administration. - ventilation usually well maintained. - laryngeal and pharyngeal reflexes maintained - Bronchodilation -> good for asthma patients - Apneustic breathing - breathe in, pause, breathe out pause etc. instead of no pause between in and out

Answer 74

- extensive hepatic metabolism in dogs and horses. - mainly excreted unchanged via the kidney, in cats - DO NOT GIVE TO A CAT WITH KIDNEY PROBLEMS - rapid recovery in most species is due to redistribution from CNS to body tissues.

Answer 75

1. CNS stimulation. 2. pain on injection (not with IV route). 3. emergence delirium. 4. hypertension and tachycardia. 5. prolonged recovery. 6. salivation. 7. increased muscle tone

Answer 76

- Not for epileptic patients or brain disorder - Increases sympathetic tone - Not in cat with kidney dysfunction - Provides analgesia - Must be used with muscle relaxant - Patient will keep oculo-palpebral, laryngeal, swallowing reflexes and the eyes will be in place with slight nystagmus - Not in glaucoma or “brain” patient

Answer 77

etomidate) - EMERGENCY DRUG - not in Aus - induction agent NOT maintenance - No CVS effect - Mild resp depression

Answer 78

Alfaxalone - lack of cumulation in the body (ideal for CRI (constant rate infusion)) - rapid, complete recovery of consciousness - lack of irritant effects and activity when given peri-venously (IM/SC routes) - No preservative (keep in the fridge - no longer than 1 week) - twitching / paddling in recovery is possible in cats -> noise induced generally Side effects - respiratory depression and decrease in arterial BP - same as propofol

Answer 79

``` Propofol - Emulsion lipid based (the white stuff) - Support bacterial growth and must be discarded 6 hours after opening (glass ampoules as well as multi-dose bottle) - Do not keep in the fridge!!!!!!!!!!!! Adverse effects - cardiovascular depression. - respiratory depression. - pain on injection (colorless > white) - can get burning affect in humans ```

Answer 80

Intravenous induction agent - phenol derivative The major benefit of propofol in veterinary anaesthesia is the “to effect” induction and the smooth, rapid recovery - Lack of excitement at induction - Lack of hangover at recovery - Non-cumulative nature - can give as infusion - Ability to use as CRI (constant rate of infusion) - Hepatic disease and kidney disease - can give in these patients

Answer 81

- hepatic metabolism and redistribution - extra-hepatic metabolism ○ lung? ○ kidney? ○ blood? - slower in cats than in dogs - 2 hour infusion for cats okay just not repeated ○ Phenol compound!!!

Answer 82

- Propofol/Thiopental 50:50 mixture - NOT USED NOW AS PROPOFOL CHEAP - Triple Drip (GGE (Muscle relaxant guaifenesin), alpha2, ketamine or thio) - Ketamine/Valium (dizepam - can be used as induction agent) (mixed)