Lecture 19 11/19/24

Question 1

What are the rates of perioperative fatality in different species?

Answer 1

dogs: 0.17%
cats: 0.24%
horses: 0.9%

Question 2

What are the stats on patients that are revived with CPR outside of anesthetic events?

Answer 2

less than 6% survive to discharge

Question 3

What are the stats on patients that are revived with CPR during an anesthetic event?

Answer 3

50% of dogs survive to discharge

Question 4

What is the easiest way to be prepared for cardiopulmonary arrest?

Answer 4

well stocked, well organized crash cart

Question 5

What can lead to a delay in CPR?

Answer 5

-missing equipment
-failure to do preventative maintenance
-equipment failure

Question 6

How long of a delay in starting CPR can lead to a huge decrease in survival?

Answer 6

10 to 20 seconds

Question 7

In addition to a good crash cart, how else can veterinary professionals prepare for CPR?

Answer 7

-learn on manikins
-undergo standardized training
-have one confident leader during CPR
-have one individual per job during CPR
-debrief following CPR about what did and did not go well

Question 8

What are the characteristics of CPA recognition?

Answer 8

-early diagnosis is crucial
-eval. should only take 5-10 seconds
-start CPR immediately in unresponsive, apneic patients
-risk of CPR in animals not in CPA is minimal; better to start CPR than do a lengthy assessment

Question 9

How can CPA be recognized on monitoring tools?

Answer 9

-loss of pulse on doppler
-stair-step waveform on EtCO2

Question 10

What are the characteristics of chest compression set up?

Answer 10

-airway management and ventilation should not delay start
-place most patients in lateral, barrel-chested dogs in dorsal
-cardiac pump in cats and pointed chest dogs
-thoracic pump in other dog breeds

Question 11

What percent of cardiac output is achieved with chest compressions?

Answer 11

20%

Question 12

What is the purpose of the cardiac pump mechanism?

Answer 12

directly compress heart

Question 13

What is the purpose of the thoracic pump mechanism?

Answer 13

rely on elastic recoil of chest to move blood

Question 14

How should chest compressions be carried out?

Answer 14

-100 to 120 compressions/minute
-1/3 to 1/2 of thorax compressed with each compression
-2 minutes uninterrupted
-no leaning on patient; reduced coronary and cranial partial pressures

Question 15

What are the characteristics of open chest CPR?

Answer 15

-better than closed chest CPR in patients with pulmonary or cardiac disease
-must make decision to do open chest CPR promptly
-intra-abdominal procedures can cut through diaphragm to perform open chest CPR
-must be prepared to manage open chest

Question 16

What are the characteristics of airway management and ventilation during CPR?

Answer 16

-does not take priority over starting chest compressions
-must intubate in lateral
-want 10 breaths/minute with a tidal vol. of 10 ml/kg
-inspiratory time should last for 1 second

Question 17

What are the characteristics of compressions and ventilation when there is a single rescuer?

Answer 17

-neck is extended
-30 compressions to 2 breaths
-no evidence for use, but no harm

Question 18

Which monitoring steps are preferred in CPR if available?

Answer 18

-EtCO2
-ECG
-doppler
-electrolytes

Question 19

What are the characteristics of EtCO2 during CPR?

Answer 19

-verification of tracheal intubation
-effectiveness of compressions
-sudden rise in EtCO2 correlates with return of spontaneous circulation
-want measurement of 18mmHg or higher for dogs and cats

Question 20

What are the characteristics of ECG during CPR?

Answer 20

-susceptible to artifact
-used to guide advanced therapy/defibrillation
-brief interruption during CPR changes to evaluate ECG

Question 21

What are the ECG rhythms of death and their shockability?

Answer 21

-asystole: not shockable
-pulseless electrical activity: not shockable
-pulseless ventricular tachycardia: shockable
-ventricular fibrillation: shockable

Question 22

What are the characteristics of defibrillation?

Answer 22

-prompt shocking of shockable rhythms has greater chance of ROSC
-will always do 2 minutes of compressions before a shock
-CPA greater than 4 minutes requires compressions/basic life support first

Question 23

What are the three phases of myocardial ischemia?

Answer 23

-electrical: 4 minutes
-circulatory: 6 minutes
-metabolic

Question 24

How does a biphasic defibrillator differ from a monophasic?

Answer 24

-monophasic sends electricity through chest once; biphasic sends electricity twice
-biphasic requires less energy
-biphasic causes less myocardial damage

Question 25

How does defibrillator energy dose differ with each shock?

Answer 25

increase dose by 50% with each subsequent shock

Question 26

Which drugs are used in advanced life support?

Answer 26

-vasopressors -parasympatholytics -IV fluid therapy -anti-arrhythmics -reversal agents

Question 27

How can emergency drugs be administered?

Answer 27

-IV if access is obtained -intra-osseus -intra-tracheal

Question 28

Which emergency drugs can be delivered via the trachea?

Answer 28

-naloxone -atropine -vasopressin -epinephrine -lidocaine

Question 29

What are the characteristics of vasopressors?

Answer 29

-cause high peripheral vascular resistance -divert blood from the limbs to the viscera -include epinephrine and vasopressin

Question 30

What are the characteristics of epinephrine?

Answer 30

-vasopressor acting at alpha1 -inotropic/chronotropic acting at beta1 -inotropic/chronotropic function harmful; increases heart rate and heart O2 requirements -only recommended in low doses

Question 31

What are the characteristics of vasopressin?

Answer 31

-vasopressor acting at V1 -no chronotropic or inotropic effects -works better than epinephrine in an acidic environment -used in place of or in combo with epinephrine

Question 32

What are the characteristics of atropine?

Answer 32

-no evidence for benefit or detriment -higher dose associated with worse outcome -drug of choice for CPA with high vagal tone

Question 33

What are the characteristics of fluid therapy during CPR?

Answer 33

-indicated in cases with hypovolemia -not recommended in euvolemic/hypervolemic cases -improper admin. can oppose blood delivery to brain and heart

Question 34

What are the characteristics of amiodarone?

Answer 34

-non-selective class III anti-arrhythmic -used for resistant pulseless v-tach and v-fib

Question 35

What are the characteristics of lidocaine?

Answer 35

-class 1B anti-arrhythmic -consider in pulseless v-tach or v-fib resistant to shock and amiodarone

Question 36

What are the characteristics of magnesium?

Answer 36

-currently not part of RECOVER guidelines -increasing number of case reports indicating magnesium helps in CPR cases

Question 37

Which reversal agents are considered in CPR?

Answer 37

-naloxone -flumazenil -atipamazole -turn off vaporizer, disconnect patient, and flush to remove inhalants

Question 38

What are the characteristics of hypocalcemia?

Answer 38

-calcium is necessary for muscle contraction and cell communication -not routinely administered -replace calcium in moderate to severe hypocalcemia cases

Question 39

What are the characteristics of hyperkalemia?

Answer 39

-common in prolonged CPA -improved outcome when treated with hemodialysis -recommended to treat

Question 40

What are the characteristics of corticosteroid use in CPR?

Answer 40

-lack of evidence -not recommended for routine use -adverse effects outweigh benefits -should be used in patients arresting due to Addison's disease -can delay ROSC and alter vascular tone

Question 41

What are the characteristics of sodium bicarb?

Answer 41

-thought to promote alkalosis in acidotic patients -can make patient more acidotic if not ventilating well -evidence of worse outcome in early CPR -used in CPR that goes longer than 10-15 minutes

Question 42

What are the characteristics of oxygen therapy?

Answer 42

-want FiO2 of 100% -maximize PaO2 in face of decreased CO -hypoxemia and reactive oxygen species can prevent ROSC -target PaO2 of 85-100mmHg