Presentation on theme: "ANESTHETIC PROBLEMS AND EMERGENCIES"— Presentation transcript:
1ANESTHETIC PROBLEMS AND EMERGENCIES The Role of the Veterinary Technician in Emergency Care
2ANESTHETIC PROBLEMS AND EMERGENCIES Anesthetic problems will inevitably occur at somepoint in your career. No anesthetic experience isthe same, so beware of the false sense of security!
3ANIMALS THAT WILL NOT STAY ANESTHETIZED Animals won’t stay anesthetizedCheck vaporizer settingCheck level of anesthetic in the vaporizerProper ET tube placement or air leakage around itPatient apneaShallow respirationsProper assembly of anesthetic machine with tight connectionsAdequate oxygen flowAnesthetic machine/vaporizer is working properlyAgonal breathing vs. light plane breathing
4ANIMALS THAT ARE TOO DEEPLY ANESTHETIZED Animals are too deeply anesthetized<6 bpm; shallow respirations, dyspneaPale/cyanotic mucous membranesCapillary refill time >2 secondsBradycardiaWeak pulse; systolic blood pressure <80 mm HgCardiac arrhythmias; irregular QRS complexes or VPCsHypothermiaAbsent reflexesFlaccid muscle toneDilated pupils
5TREATING EXCESSIVE ANESTHETIC DEPTH ADJUST THE VAPORIZER:NOTIFY THE VETERINARIAN:BAG THE ANIMAL1. Close the pop-off valve2. fill the reservoir bag with oxygen3. gently squeeze the bag until the patient’s chest rises slightly (15-20 cm H2O)4. Repeat until animal shows signs of recovery
6PALE MUCOUS MEMBRANES Pale mucous membranes Preexisting conditions Blood loss during surgeryAnesthetic agent that causes vasodilation and hypotensionHypothermiaPain
7TREATMENT OF PALE MUCOUS MEMBRANES Ascertain the animal’s anesthetic depth:HR, RR, pulse quality, CRTConsult the veterinarianFluids, blood transfusion
8Anesthetic Problems and Emergencies (Cont’d) Prolonged capillary refill time (>2 seconds)Blood pressure cannot adequately perfuse superficial tissuesMay result from conditions present prior to inductionMay be secondary to blood loss during surgeryMay be seen in animals in deep anesthesia
9DYSPNEA AND/OR CYANOSIS DYSPNEA: respiratory difficultyCYANOSIS: bluish coloration of the mucous membranes indicating inadequate tissue oxygenationAssessmentRespiratory character and volumeDepth of anesthesiaAssociated with painProper ET tube placementET tube blockageOxygen saturationArterial or end-tidal CO2
10Treatment of cyanosis/dyspnea 1. Check O2 flow meter2. Turn off vaporizer and begin to bag the patient (IPPV)If the anesthetic machine is unavailable, an Ambu bag can be used to deliver room air3. Reintubate if necessary4. Continue until patient improves5. Close monitoring to ensure that cardiac arrest does not occurRadiographs and thoracocentesis might be needed
11TACHYPNEA TACHYPNEA: rapid respirations CAUSES: Surgical stimulation Commonly seen with opioid useAssociated with light anesthesia accompanied by tachycardia and spontaneous movementMay be seen in hyperthermic animals
12TREATMENT OF TACHYPNEA CHECK ANESTHETIC DEPTHIs the animal too light?CAPNOGRAPH READINGObese patientsAssist or control ventilation
13RESPIRATORY ARREST Cessation of respiratory efforts Not all cases require immediate action by the anesthetist:Cessation of respiratory effortsCan lead to cardiac arrestTemporary arrestMay follow injection of respiratory depressants or following a period of prolonged baggingEvaluate other vital signsHR/pulse quality:MM:ECGPulse oximeter reading:
14Respiratory arrest (Cont’d) True arrestRequires immediate actionCan result from anesthetic overdose, cessation of oxygen flow, or preexisting respiratory diseaseMay be preceded by dyspnea or cyanosis and abnormal vital signsMay use Ambu bag, mouth-to-ET tube, or mouth-to-muzzle resuscitation
16TREATMENT OF TRUE RESPIRATORY ARREST 1. NOTIFY THE VETERINARIAN2. Turn off the vaporizer3. Place ET tube if not already doneEmergency tracheotomy?4.Monitor for cardiac arrest5.Restore oxygen flow and begin bagging the patient6. Continue bagging every 5 seconds until vital signs improve7. Administer shock fluids- Dr. can decide on Dopram or reversal8. Preserve warmth
17CARDIAC ARREST No heartbeat is auscultated or palpated Normal QRS complexes are absentNo arterial pulse and blood pressure <25 mm HgGray or cyanotic mucous membranesWidely dilated pupils, no corneal reflexAgonal breathingSome prior warning is usually presentRespiratory distress or arrest, cyanosis/dyspnea, prolonged capillary refill time, arrhythmia
18Updated with information from the ACVECC-RECOVER Study 2012 CPRCardioPulmonary ResuscitationUpdated with information from the ACVECC-RECOVER Study 2012
19Anesthetic Problems and Emergencies Cardiac arrest with CPCR (cardio-pulmonary cerebrovascular resuscitation)A = airwayB = breathingC = circulationD = drugsE = ECGF= FluidsCirculation is the most important step so the correct order is CABDE
20CPR Human Medicine Veterinary Medicine Cardiac arrest: 330,000 people per year dieSurvival to discharge:Out-of-hospital arrest: <6.4%Veterinary MedicineTotal arrest numbers unknownIn-hospital-arrest:Dogs 4%Cats 4-9.6%
21The most successful CPR is one that is averted! PREVENTIONThe most successful CPR is one that is averted!Know which patients are risk.Know the warning signs.
23Warning signsChanges in respiratory rate and characterWeak irregular pulsesBradycardiaHypotensionCyanosisHypothermia
24Preparedness/Readiness Time is criticalTo Increase chances of success…Early recognitionKnow patient’s code statusPersonnelDedicated spaceEquipment
25Recognition of arrest Loss of consciousness No respirations No palpable pulsesPupils fixed and dilatedCRT prolonged or absentMM pale, grey, cyanotic
26Who should be resuscitated? Patients with reversible diseaseWhen doubts exist perform CPRDiscuss and educate client at admission!
27Personnel responsibilities There is a critical 4 MIN window to restore oxygen delivery to the brain!Team Effort: Doctors and Technicians (5 techs 1 doctor)Central person making decisions (DVM)Chest compressionsManual ventilationDrug administrationSetting up monitoring equipmentRecording events
29Crash Cart Cuffed endotracheal tubes Laryngoscope 4-6 sizesLaryngoscopeSyringes, needles of various sizesCatheters: Intravenous, intraosseous, red rubberDefibrillatorDrugsEpinephrine, atropine, vasopressinNaloxoneSmall surgery packSuction unit
30Phases of Resuscitation Basic Life SupportABC’SAdvanced Life SupportABC plus D: Drugs & DefibrillationPost-Arrest: Prolonged Life Support
31ABC’s Airway Should have 4-6 sizes of cuffed ET tubes available LaryngoscopeMake sure airway is clearSuction airway if necessaryCapture and secure airway!!
32CARDIAC ARREST - ABCDEF AIRWAY and BREATHING;IMMEDIATELY CALL FOR HELP, NOTE THE TIME!An Endotracheal tube must be placed!Begin bagging at 1 breath every seconds (1:5 breath to compressions)Do not overinflate
33Breathing Utilization of ambu bag connected to oxygen source Provide manual ventilatory supportVentilation of dogs and cats with CPA at a rate of 10 breaths per minute with a tidal volume of 10ml/kg and an inspiratory time of 1 sec is recommended.
34Circulation External chest compressions Positioning Thoracic pump theoryCardiac pump theoryPositioningLateral recumbencyFirm surfaceMedium and large dogsSmall dogs and cats
35CARDIAC ARREST - ABCDEF CIRCULATION – cardiac compressions should be initiatedCompressions manually force blood through the heart and into tissuesPOSITIONING: right side down with legs toward the compressorLARGE DOGS: The heel of the compressor’s hand should compress the chest against a firm object placed under the dog’s chest just behind the elbow. Also, dog can be placed in dorsal recumbency and compression applied to the caudal 1/3 of the sternum
36CARDIAC ARREST - ABCDEF Medium sized dogs: The chest is compressed between two hands, one underneath the chest and the other at the 5th intercostal space over the heart itself.Small dogs or cats: compression applied using the thumb to compress the chest against the fingers of the same hand.
37Circulation Cardiac compressions Most important factor is return of spontaneous circulation (ROSC)Cardiac compressionsEach compression should produce a palpable femoral pulseRate of compressions : / minuteCompressions should be continuousAllow full chest wall recoil30-50% chest compression depth1:1 ratio compression/relaxationChange compressor every 2 minutes
38Circulation (Cont’d)Bag the patient every secondsSimultaneously with compressionsSome results should be seen within 2 minutesInternal compressions may be necessaryResuscitation is unlikely to be successful after 15 minutesOnce spontaneous cardiac contractions are established, continue bagging until spontaneous breathing is established (several hours)
39These patients are not on their right side- boooo
40Indications for open chest CPR Owner wishes??Thoracic traumaPericardial fluidNo response to CPR after 3-5 minutesChest or abdominal surgery
41ABC plus D Drugs Defibrillator Doppler Advanced Life Support Veterinarian authorizes dosage, route, and nature of drugs
42Drugs Epinephrine – 0.01 mg/kg Atropine – 0.05 mg/kg Alpha 2-adrenergic stimulator: vasoconstrictionGive every 3 to 5 minutes during CPRAtropine – 0.05 mg/kgAnticholinergic parasympatholytic: Increases HRAsystole and PEAVasopressin – 0.8 u/kgPeripheral vasoconstrictionDilation of cerebral vasculatureAsystole, prolonged arrestDopamine or dobutamineIncrease force and rate of cardiac contractions
44Drug admnistration routes IV (intravenous)IT (intratracheal)Double dose of drugNever give Na bicarb ITIO (intraosseous)IC (intracardiac) NOT RECOMMENDEDRisk of coronary vasculature laceration in closed-chestOK in open-chest
47Asystole Most common arrest rhythm NO drugs have proven effective Vasopressin shows some promiseContinue CPR or stop
48Pulseless Electrical activity Electrical activity but no myocardial contractionFormerly know as EMD (electrical mechanical dissociation)NO drugs proven effectiveContinue CPR or stop
49Ventricular Fibrillation Two formsCoarseHigher amplitude more orderly appearanceEasier to convert with defibrillationFineLower amplitude, complete lack of organizationCarries poorer prognosis, more difficult to convertCan be mistaken for asystoleRecommended treatment: Immediate defibrillation
51Auscultation, palpation of pulses MonitoringETCO2Doppler on cornea~Cerebral blood flowAuscultation, palpation of pulses
52Advanced life support: cont- Fluids IV fluids (crystalloids)IF EUVOLEMIC:*DO NOT GIVE SHOCK DOSES*Decreased CPPIncreased right atrial pressure relative to aortic pressureIf hypovolemicShock dose: 90ml/kg dogs, 40-60ml/kg catsStart with ¼ shock dose
53Monitor cardiovascular and respiratory function Blood pressure, blood gases, pulse oximetry, ECG, capnographyDrug and fluid therapy variesAssess brain functionRepeat arrest within 24 hours is commonFollowing successful ROSC, other conditions may arisePulmonary or cerebral edema
54Wrap Up Prevention Preparedness Early recognition Know patient’s code statusDedicated space, personnel, equipmentKNOW YOUR ABC’s!
55Other occurrences during surgery but not necessarily an emergency Regurgitation during anesthesiaA passive process under anesthesiaNo retching, just fluid draining from animal’s mouth or noseStomach contents may be aspirated into respiratory tractMost common occurrence in head-down surgical positions and in ruminantsTreatmentImmediate placement of cuffed ET tubeClean out regurgitated material with suction
56Post op complications Vomiting during or after anesthesia Common in brachycephalic dogs or nonfasted animalsAn active process usually accompanied by retchingUsually occurs as the animal is losing or regaining consciousnessSignsAirway obstruction leading to dyspnea/cyanosis, bronchospasmTreatmentIntubation and suction if unconsciousLower head and clean oral cavity if conscious
57SeizuresSeen with ketamine administration, after diagnostic procedures (myelography), or preexisting conditionsSignsSpontaneous twitching; uncontrolled movements of head, neck, and limbs; opisthotonus; triggered by a stimulusTreatmentReduce stimuli, postoperative analgesia, diazepam or propofol, monitor for hyperthermia
58Seizures should be differentiated from excitement Seen after barbiturate anesthesia or high opioid doses, as spontaneous paddling and vocalizationTreatment may not be necessarySedatives may helpNaloxone can reverse opioidsSeizures should be differentiated from excitement
59Dyspnea in catsDyspnea is usually caused by laryngospasm sometimes triggered by removal of the ET tubeLaryngeal edema may result from repeated intubation attemptsMay breathe with an audible stertor (wheeze) during inspirationDifferentiate from growling during expirationMay resolve itself or may need oxygen administration via facemask, intubation, or a tracheotomyIs easier to prevent than treat
60Dyspnea in dogs Breed-related Airway obstruction Brachycephalic dogsAirway obstructionAnatomy, foreign objects, postsurgical tissue swellingHumidified oxygen can be delivered to an awake animalBy facemask, nasal cannula, E-collar, or oxygen cage/tent