Response to Anesthetic Problems and Emergencies Anesthetist and Recovery We are going to talk about your response to: Depth of anesthesia issues Cardiac arrest Recovery period problems

ANIMALS THAT WILL NOT STAY ANESTHETIZED Double-check equipment Vaporizer Oxygen supply ET tube Double-check the patient Respirations Rapid and shallow? Apneic?

ANIMALS THAT ARE TOO DEEPLY ANESTHETIZED Respirations per min: MM/CRT: Heart rate: bradycardia ECG: Pulse quality: Temperature: Pupils:

TREATING EXCESSIVE ANESTHETIC DEPTH Lower vaporizer setting Notify veterinarian Manually ventilate the patient 1. Close the pop-off valve 2. Fill the reservoir bag with pure oxygen and provide PPV 3. Repeat until animal shows signs of recovery Reversals? Fluids? Warmth

RESPIRATORY ARREST -is it true? Patient is not breathing on their own Doesn’t always require action: 1. 2. Assess other vitals:

RESPIRATORY ARREST True respiratory arrest: Begin manually ventilating Warning signs: Begin manually ventilating Continue until vitals improve… Then give them a chance! *What if you don’t have an anesthetic machine?

CARDIAC ARREST A sudden cessation of effective ventilation and circulation. Signs it’s coming: Cyanosis Respiratory arrest CRT > 2 sec Weak arterial pulse Very low BP readings Abnormal ECG tracing VPCs V-fibrillation

CARDIAC ARREST Signs it’s here: No heart beat auscultated No palpable arterial pulse MM gray BP <25 mmHg Agonal breath Asystole seen on ECG Initiate CPCR: a team effort! ASK FOR HELP

CARDIAC ARREST – ABCDE??? There is a critical window to restore oxygen delivery to the brain How long?? Ideally, 5 people would participate in the resuscitative efforts (CPCR) Performs chest compressions Bags the animal Assess the pulse during compressions and the ECG when compressions are temporarily suspended Draws up and administers drugs on the veterinarian’s orders Maintains a record of procedure

CARDIAC ARREST – CABDE Circulation restoration is most important Artificially supply heart, lungs, and brain with oxygenated blood Start compressions! Positioning Slightly different based on P size

CARDIAC ARREST - CABDE Circulation Compression rate= 1-2 times per second ~80 times per minute for a large dog ~120 times for small dogs or cats Chest should be compressed ~1/3 to 1/2 the diameter of the chest wall Should feel a femoral pulse with each compression Will also stimulate gas exchange

**Circulation should take priority over breathing, if working alone** CARDIAC ARREST - CABDE Compressions and bagging should be administered simultaneously. Switch personnel every two minutes **Circulation should take priority over breathing, if working alone** What are you looking for?

CARDIAC ARREST - CABDE Advanced Life Support Defibrillation may be started Electric shock (J/kg) No alcohol if defibrillating! May switch to internal massage What procedure would be performed? Prep between ribs 7-8 Invasive, but can get higher return of CO

CARDIAC ARREST - CABDE Once CPCR is initiated: Continue compressions until you have return of spontaneous circulation Palpate pulse, continue ECG, auscultate continuously Continue bagging after beat is back

CARDIAC ARREST - CABDE Airway and Breathing Intubate 100% oxygen Ventilate every 10 seconds

CARDIAC ARREST - CABDE Advanced Life Support Drugs: Routes: Epinephrine Dopamine/dobutamine Atropine Lidocaine Routes: IV- drugs, fluids IT – drugs IC – last resort for drugs

ECG CARDIAC ARREST - CABDE Periodically check for spontaneous contractions by discontinuing external compression Done by either palpating for a pulse or looking for QRS complexes on the ECG. Downside?

CARDIAC ARREST After Care: Common for patient to repeat arrest within 24 hours Neurological tests needed Must be monitored extremely close

Prepare for Success! Have emergency supplies in a central location Check frequently!

Prepare for Success! Post algorithms in treatment areas Make emergency dosing charts Calculated volumes of drugs based on weight classes

Recovery Period Problems Regurgitation: Vomiting: Solutions: FASTING Pre-ax drugs? Injectable anesthetics Quick intubation with cuffed ET tubes Leaving ET tube in place until P has swallow reflex

Recovery Period Problems Seizures- spontaneous, uncontrolled twitching Differentiate from reverse excitement phase, dysphoria, and/or pain Animals that might have a rough recovery? Solutions: Seizures: Remove external stimuli Diazepam IV; possibly PR Monitor for hyperthermia Dysphoria: Propofol or alpha-2

Recovery Period Problems Dyspnea- most common cause of post-Ax death *When is this most likely to occur? Cats: laryngospasms  reflex closure of trachea Prevention: extubate before reflex returns Trauma to tracheal opening during intubation? Solution: Check MM, SpO2 and positioning Provide oxygen Re-intubate if patient is crashing What if you can’t intubate?

Recovery Period Problems Dyspnea- most common cause of post-Ax death Dogs: extubated too early or have extra tissue blocking tracheal opening Which breeds more susceptible? Prevention: leave tube in as long as possible Longer if the intubation was difficult Monitor positioning after extubation Solution: Check MM, SpO2 and positioning Provide oxygen Re-intubate if patient is crashing

Recovery Period Problems Prolonged recovery phase Individual susceptibility to Ax drugs Hypothermic Prolonged anesthesia; excessive depth reached Prevention: fluid therapy during sx; start warming ASAP Solution: Warm them up! Reversals if available

Reading Assignment Pages 336-337 Other reasons for the clinical signs of being too deeply anesthetized: (Start at Pale MM, stop at Respiratory Arrest) I would suggest reviewing the entire chapter, chapter key points, and Procedures 12-1 through 12-11.