Anaesthesia accidents and emergencies Flashcards
Why might anaesthetic accidents happen?
- Largely avoidable
- Sick patients
- Equipment failure
- Inadequate preparation
- Inadequate monitoring
- Most often a combo of the above
- Never make the same mistake twice
- Check lists are vital
What is a complication?
An event that develops but is not due to human error (it would happen regardless) e.g. hypotension/ haemorrhage/ drug reaction.
What is an error?
An avoidable event, ie APL valve left shut/ patient given wrong dose of drug.
What human errors can ocur?
- Drug administration errors
- Incomplete clinical assessment - Inadequate knowledge of the machine/
protocols - Failure to appropriately monitor the animal - Closed APL Valve
What equipment failure and errors can go wrong?
- Inability to deliver an appropriate oxygen supply
- Lack of oxygen in cylinder/ source
- Disconnection of piped o2
- Stuck or missing one way valve
- Leaks in the machine/ breathing system- Ventilator failure
What are the complications that can occur when placing an IV catheter?
- Trauma during insertion
- Lack of placement (ie outside of vessel)
- Infection/ inflammation
- Phlebitis- Dislodged from vein
- Air embolism
- Pain/ discomfort
How can we prevent IV catheter complications
- Aseptic technique
- Start low down on limb (more space to move up!)
- Correct catheter type
- Good technique/ adequate restraint
- Prevent patient interference
- Daily/ twice daily observation and dressing change
- Regular flushing
- Know your own limitations/ skills/ when to give up
What drug administration errors can occur?
- Wrong drug given
- Wrong dose/ concentration given
- Incorrect route used E.g. ketamine used to flush IV line
- Miscommunication
How can we avoid drug administration errors?
- Double check our calculations
- Have an accurate weight
- Label syringes
- Understand pharmacology
- Check medication form before administration
- Record all drugs given
- Careful preparation- ensure correct drug!
- Confirm route of admin – check data sheet/ drug bottle
-Train your team
What should we do if we spot a drug error?
- tell the Vet
- If not all given, STOP!
- Carefully monitor animal
- Check drug bottle/ data sheet for info
- Contact poisons service if concerned/ warranted
- Inform owner
What is vomiting?
active process
What is regurgitation?
passive process without GI contractiona
What is reflux?
technically regurge in an anaesthetised patietn
What are the risk factors associated with gastro oesophageal reflux?
- excessive/ inadequate pre-operative fasting
- Drugs
- Abdominal pressure - Abdominal surgery/ long ops
- Orthopaedics
How can we lower the risk of gastro oesophageal reflux?
- Appropriate pre-operative fasting times.
- Identify at risk patients.
- Pre-operative GI protectants (at direction of Veterinary Surgeon)
- Head up/ swift induction.
- Cuffed endotracheal tube.
- Have suction available
What should I do if I see Regurgitation
- Head down
- Suction/ swab out pharynx
- Consider Omeprazole IV in animals known to be at risk (at direction
of Veterinary Surgeon) - Record on anaesthetic record
- Inform vet.
How can I prevent ocular damage?
- Care with warming devices
- Careful positioning
- Be aware of placement of face masks
- Avoid droplets/ liquids around face area
- Avoid trauma
- Regular use of an ophthalmic ointment ‘fake tears’
- Be aware of your environment
What do I do if I see an ulcer during/ following anaesthesia
- Prevent rubbing/ scratching
- Inform veterinary surgeon
- Potential- start eye ointments/ continue at home
- Identify reason- if you can
- Inform owner
Why does hypothermia occur and why can it cause issues?
- Can lead to increased mortality especially in sick animals
- Cardiac arrhythmias : - Atrial fibrillation – 30 degrees
- Ventricular fibrillation – 24-28degrees
- Bradycardia
- Impaired coagulation and wound healing
- Shivering = increased oxygen demand
How does hypothermia impact anaesthesia?
- Prolonged duration of action of drugs
- Decreased renal plasma flow
- Decreased oxygen delivery to tissues
- Lower anaesthetic requirement
How can you prevent hypothermia?
- Insulation
- Warm from point of premedication
- Avoid leaving pre-medicated animals unsupervised
- HME ( heat moisture exchange) breathing system Clipping and scrub solution- care
- External heat sources
- Warm environmental temperature
- Avoid excessive lengths of anaesthesia
What rate ofhyperthermia can cause ddeath?
over43 degrees
What can hyperthermia cause?
- parenchymal cell damage
- increased oxygen requirement
- increased metabolic rate
How can i avoid hyperthermia?
- Close observation of patient warming
- Never leave an animal on a heat source that they are unable to move away from
- Avoid microwave heat sources- they do not distribute heat evenly
- Identify at risk animals-
- Provide cooling if needed – fan/ wet towels/ cold water lavage
How can I recognise Respiratory Tract Obstruction?
- May be breed ( brachy) or condition ( laryngeal mass) related
- Increased respiratory effort - Paradoxical ventilation
- No air movement nose / mouth
- Possibly cyanotic MMs
- Capnography changes
- CAREFUL observation
What is paradoxical breathing?
occurs when the chest wall or the abdominal wall moves in when taking a breath and
moves out when exhaling
Why might a patient be apnoeic, in respiratory arrest or cyanotic?
- May be due to depth i.e. too light/ too deep
- May be due to unnoticed respiratory tract obstruction
- May be drug related e.g. fentanyl/ NMB/ post induction apnoea
- Cyanosis may be due to inadequate o2 supply
- Cyanosis may be due to a very low cardiac output
What do I do if I notice Respiratory Tract
Obstruction?
Inform surgeon/ Vet.
- Will depend on the cause and if ETT in place or not
- Straighten neck, pull tongue forward, check mouth and pharynx- suction if needed
- Check o2 source/ check of equipment
- Oxygen
- Intubate
- Corticosteroids if indicated and prescribed by Veterinary Surgeon (NB identify at risk patients re NSAIDS)
- Have equipment prepared eg brachy
- Pre-oxygenate before potentially difficult intubation
What can you do if you think there is a respiratory tract obstruction but the patient is intubated?
- Check ETT is not kinked, obstructed, too long, faulty
- Check breathing system
- Check oxygen supply
What should you do is a patient is apnoeic or cyanotic?
- Confirm heartbeat
- Check depths of anaesthesia
- Check for obstruction/ obvious reason for
apnoea - Ensure 100% oxygen is given- ie ensure MV
given - Manually ventilate the lungs, check breathing
system, tube, confirm chest wall movement - Specific antagonist if appropriate (as per VS)
-Turn off volatile agent
What can cause cardiac arrest?
- Pre-existing cardiovascular disease
- Anaesthetic overdose
- Hypovolaemia
- Electrolyte/ acid base abnormalities
- Vagal reflex
- Respiratory arrest
What should you do if you detect cardiac arrest?
- Check pulse/ heart rate- confirm CARDIAC COMPRESSIONS
- Check ventilation – confirm
- Check depth of anaesthesia - Turn off anaesthetic agent?
- Ensure 100% oxygen is given
- Manually ventilate the lungs, check breathing system, tube, confirm chest wall movement
What is an arrhythmia?
A change in rhythm, rate or origin that differs from the normal
cardiac cycle
What is 1st degree block?
The electrical signal struggles to get through each time but does get through! Signal is ‘held up’!
What is 2nd degree block?
1- Wenckebach
- May see a progressive lengthening of the PR interval until the gap is so large you start to loose beats.
- Will see a steady prolongation in length between P and R2- Mobitz
- We stil have intermittent passage through the AV Node but we don’t get the pre-warning that we had with Type 1.
-Beat just drops (se pic on next slide)
What is ventricular tachycardia?
Very rapid heart rate caused by abnormal complexes that have been generated by the ventricles (this is why the trace looks so large and bizarre, the ventricles are larger than the atria)
