CPR Flashcards
When is the safest time for an animal to arrest?
Under anaesthesia
Is it likely that you will be able to revive a animal dead on arrival?
no but always try and help even if just taking them out the back
What is CPR?
- patient stops breathing OR its heart stops beating
(minute after respiratory arrest before cardiac arrest follows, if under GA oxygen levels ^ so 5 minutes) - means to support circulation and oxygenation
define rsp/cardiorespiratory arrest
- cessation of effective breathing
- cessation of effective cardiac activity (CO) and respiration
Define return of spontaneous circulation (ROSC)
- re-establishmenet of sustained CO without assistance (not just electrical activity - pulseless electrical activity)
Define basic life support
- chest compressions and assisted ventilation
Define advanced life support
- BLS + medical and electrical intervention
What is CPCR?
- cardiopulmonary CEREBRAL resuscitation
- rescusitative efforts required to elicit ROC and emphasising the importance of neuroplogical outcome
- mainly in humans (dropping core temperature etc.)
- dogs and cats more tolerant of periods of hypoxia
How can impending cardiopulmonary arrest be recognised?
- not easy in critically ill patients
- hypoventilation and bradycardia esp if sudden
> pre-arrest rhythms - ventricular tachycardia with R on T phenomenon (no return to baseline, no repolarisation)
- ventricular flutter/fibrillation (needs defib within mins)
- third degree AV block (dissociated of atria and ventricles, ventricles will beat d/t escape complexes @ 40bpm, needs pacemaker)
How can an arrested patient be identified?
- spontaneous breathing efforts
- auscult heart
- feel for apex beat
- palpate pulses
Most common cause of CPA in animals cf. people?
- airway obstruction (always intubate)
- humans more likely myocardial infarction
How many people are needed for effective CPR?
3-4 people min - ventilation - compressions - IV access - ECG - runner - scribe - pulse taker (spontaneous or compressions) - abdominal counterpressure to divert blood to cranial vena cava and brain > one person should take charge
What is vasovagal syncope and vagal arrest?
- stimulation of vagus nervie -> life threatening bradycardia
> causes of vagal stimulation - V+
- defeacation/urination
- respiratory arreat
- ocular or neck surgery
- patients with pre-existing high vagal tone pdf
Tx high vagal tone?
Atropine (parasympatholytic)
- intubate
- oxygenate
- can anaesthesise
Causes and tx of anaesthetic related arrest?
- OD anaesthetic (stop giving anaesthetic, reverse)
- hypoventilation/hypxia/hypercarbia
Complications of anesthetic CPA?
hypoxia leads to... - blindness - dysphoria - neuro dysfunction > most go away with time and good nursing care
How can positive pressure respiration be given?
- positive pressure on anaesthetic machine
- Ambu bag (regulates pressure so you cant overdo it)
- 10-12 breaths per minute (don’t hyperventilate!! CO2 taken off too much -> vasoconstriction)
- 100% oxygen
- deliver breaths simultaneous with compressions
- max pressure 15cmH20 cat, 20cm H2O dog)
- inspiratory time
What does too much ventilation do
- ^ intrathoracic pressure
- v CO
- v cerebral and coronary perfusion
Aim of circulatory support?
- maximise myocardial/cerebral perfusion
- myocardial perfusion depends on DIASTOLIC pressure
- cerebral perfusion depends on MAP
- minimise interruption of compressions
How is CPR physically carried out?
7kg
- compress thorax (thoracic pump mechanism)
~ 100bpm
~ 50:50 duty cycle (let chest expand between compressions)
How often should you switch people compressing?
2 minutes
Indications ofr open chest CPR?
- large dogs
- significant pleural space disease
- chest wall disease
- pericardial effusion
- penetrating chest wounds
- intra-operative arrests (esp abdo, cut through diaphragm)
- haemoabdomen
- unwitnessed arrests
- unsuccessful closed chest CPR (after 5-10mins? no proof for this)
Advantages of open chest CPR
- diastolic filling assessment
- pericardial tamponade avoided
- aorta cross clamped
- ventricular fibrillation visually diagnosed
- myocardial flaccidity assessed directly
Disadvantages of open chest CPR?
- need experienced personel
- need more personnel
- significant procedure
- financial and surgical backup
- infection (non-sterile)
What is involved in advanced life support?
- determin arrest rhythem
- defib
- cardiac pacing
- vascular access
> drugs - vasopressor (adrenaline)
- vagolytic (atropine)
- antiarrythmic (lidocaine)
- buffer (acidosis eetc.)
- electrolyte
- IVFT
Is VF common in small animals? Wht is the only tx method?
No (cf. humans)
- need defib to convert
- can try pre-cordial thump
Which drugs can be given ET if no venous accccess present?
Lipid soluble: N- naloxone A - atropine V - vasopressin E - Epinephrine L - Lidocaine > NOT ca or bicarb
Has any drug tx been shown to ^ survival?
NO
What does atropine do? Indications?
> vagally mediated arrests
- parasympatholytic
- accelerates pacemakers
- ^ AV conduction
What does epinephrine do? Indications?
> standard vasopressor for cardiac arrest
- a– mediatedvasoconstriction, ^ aortic pressure, ^ myocardial perfusion
What does calcium do? Indications?
> previous hx of hyperkalaemia, hypoclcaemia
- specific indications only
What does glucose do? Indications?
> Tx hypoglycaemia pre/during arrest
- check glucose during CPA, tx hypoglycaemia as required
What does lidocaine do? Indications?
> ventricular tachycardia
- v automacity an suppresses ventricular arrhythmias, less effective than amiodarone
What is sodium bicarbonate? Indications?
> hyperkalaemia/metabolic acidosis
- routine administration does not improve outcome
What is vasopressin? Indications?
> Vasopressor
- some theoretical advantages over epi
- inconsistent results
- only neeed to give once
What is always indicated for severe bradycardia?
Atropine
Side effects of atropine?
- may contribute to development and maintainence of PEA/asystole
- may potentiate sinus tachycardia
- may encourage VF when given in the vicinity of epinephrine
> give one dose in early CPR
When are IV fluids indicated?
> NOT AS STANDARD - following drug administration - pre-existing severe hypovolaemia - bleeding out > overhydrating decreases coronary perfusion (^ right sided heart pressure)
When is the majority of ROSC successful? When can you ggive up?
8-10 minutes
- check end tidal CO2, if zero give up
- after 30 mins probably ok to give up if no signs of life
