Anesthetic Problems and Emergencies A&A Chapter 12 pg. 319- 349

Why Do Problems Arise? Human error Equipment error Drug adverse effects Patient factors Anesthetic problems will inevitably occur at some point in your career. No anesthetic experience is the same, so beware of the false sense of security!

Human Error Failure to obtain an adequate history or physical exam on the patient Ideally, every patient scheduled for anesthesia should have a complete PE, and a thorough history obtained with the owner present. *Less than ideal circumstances are common: Owner drops patient off in a hurry Patient brought in by neighbor or friend Receptionist takes the history HISTORY?

Human Error Lack of familiarity with the anesthetic machine or drugs Thank goodness for LVTs!

Human Error Fatigue Distracted or rushed Inattentiveness Proper scheduling of surgeries can help with this Distracted or rushed Usually you have your surgical patient and… Inattentiveness Having a low level of anxiety is good!

Human Error Incorrect administration of drugs Inaccurate weight Units, scale is off Math errors – calculating OR drawing up Use of wrong medication Use of wrong concentration Enro, ketamine, dexmed, pred Incorrect route of administration IV v. IM Confusion between syringes

Equipment Failure CO2 ABSORBER EXHAUSTION How is CO2 removed from a rebreathing system? How is CO2 removed from a non-rebreathing system? Best way to keep an eye on exhaled CO2? ↑ CO2 = Tachypnea, tachycardia, cardiac arrhythmias

Equipment Failure NO OXYGEN FLOW Which two parts of the machine may be malfunctioning? Oxygen tank: check for empty tank, disconnected hose, leaks Flow meter: will gradually fall as the O2 tank empties Periodically check this! *Which breathing system can go without new O2 flow longer?

Equipment Failure ANESTHETIC MACHINE MISASSEMBLED The better you know this machine and the flow of gas, the quicker you will be able to solve problems. *Where do some of the most common misassembled parts happen on the machine?

Equipment Failure ENDOTRACHEAL TUBE PROBLEMS Blocked tube Twisting or kinking of the tube (inappropriate positioning) Accumulation of material such as blood, mucus, excess lubricant *What tubes do you need to pay special attention to? Blocked tube = decreased oxygen to patient Solution: Check signs of tube properly in the trachea If truly blocked  extubate or suction with RRC

Equipment Failure ENDOTRACHEAL TUBE PROBLEMS Tube advanced too far into a bronchus How do you solve this? Cuff or tube is damaged Solution?

Equipment Failure Wrong anesthetic in the vaporizer VAPORIZER PROBLEMS Wrong anesthetic in the vaporizer Non-precise concentrations delivered Solution: Tipped over or over-filled Vaporizer dial may be jammed

Equipment Failure POP-OFF VALVE PROBLEMS The pop-off valve is inadvertently left closed pressure builds  patient cannot exhale =rupture of lungs and decreased venous return to Two reasons why pop off would be left closed? Solution: *Can adjust the amount of gas in the reservoir bag by adjusting the pop off valve

Anesthetic Agents “Every injectable or inhalation agent has the potential to harm a patient and, in some cases, cause death”. (Page 323) Review the description of the physiological effects of pre-anesthetic and general anesthetic agents in chapter 3.

Anesthetic Agents Anesthetic protocol should be chosen based on the patient’s needs Anesthetist must be familiar with side effects Such as? Why is balanced anesthesia safer?

Patient Factors Trauma Age Weight Breed Organ disease Urinary obstruction

Patient Factors TRAUMA PATIENTS Potential Problems: Physical Status Classification= P3, P4 or P5 Potential Problems: Respiratory distress Pneumothorax: No negative pressure  lung tissue collapse Pleural effusion: Fluid compressing lung expansion  lung tissue collapse Pulmonary contusions/edema: No gas exchange

Patient Factors TRAUMA PATIENTS Respiratory distress Solution: FLUID AND/OR AIR SHOULD BE REMOVED BEFORE ANESTHESIA Aseptic prep: Lateral chest wall 7th-9th intercostal spaces Clip and scrub

Patient Factors TRAUMA PATIENTS Respiratory distress Solution: What therapy might we provide for the patient while they are stabilizing?

Patient Factors TRAUMA PATIENTS Potential Problems: Cardiac arrhythmias Pre-anesthetic ECG What drug should you have on hand and know the dose for? Shock/hemorrhage What fluids might you prep? Fractures/organ rupture anemia Unknown internal injuries…what diagnostic test??

Patient Factors TRAUMA PATIENTS Solutions: Stabilize patient- may be hours to days decrease anesthetic risk! Obtain rads, ECG, blood work

Patient Factors-Group Discussion Geriatric Pediatric Brachycephalic Sighthounds Obese Cesarean Neonates Cardiovascular disease Respiratory disease Hepatic disease Renal disease/Blocked Tom ASA Physical Status Classification (pg. 25) Patient description and example Potential problems Solutions