Conduct of General Anaesthesia Flashcards
What are some roles of the anaethetist?
- Pre-operative assessment
- Perioperative medicine
- Pain medicine
- Critical care/intensive care medicine
- Anaesthesia
What are the 4 anaesthetic stages?
- Induction
- Maintenance
- Emergence
- Recovery
What are the stages and phases of patients journey to theatre?
- Pre-operative assessment and planning
- Preparation
- Anaesthetic stages
- Induction
- Maintenance
- Emergence
- Recovery
- Post-operative care
What does preparation for theatre involve?
- Right people, skills, place and time
- Machine checks
- Brief
- Check-in patient
- Correct patient, correct procedure, correctly marked site, consent
- Apply monitoring to patient
- 5 minimum standards of monitoring defined by association of anaesthetists minimum standards
- ECG
- Oxygen saturation
- Non-invasive blood pressure (BP normally decreases)
- End tidal CO2 (amount of CO2 in gas patient is breathing out)
- Airway pressure monitoring
- 5 minimum standards of monitoring defined by association of anaesthetists minimum standards
- IV access
- Pre-oxygenation (patients may stop breathing under anaesthetic, muscles relax so total volume in lungs reduces so this is done to increase time to desaturation)
What does checking in the patient involve?
Correct patient, correct procedure, correctly marked site, consent
What are the 5 minimum standards of monitoring defined by association of anaethetists minimum standards?
- ECG
- Oxygen saturation
- Non-invasive blood pressure (BP normally decreases)
- End tidal CO2 (amount of CO2 in gas patient is breathing out)
- Airway pressure monitoring
WHat is end tidal CO2?
End tidal CO2 (amount of CO2 in gas patient is breathing out)
What can induction of anaesthesia be performed by?
- IV
- Fast onset
- Usual combination of drugs is analgesic (fentanyl or alfentanil) with a hypnotic (propofol, thiopentone or ketamine) and sometimes a muscle relaxant
- Inhalation
- Unusual in adult, normally done for children
- Slow onset
What is the usual combination of drugs for IV induction of anaesthesia?
- Usual combination of drugs is analgesic (fentanyl or alfentanil) with a hypnotic (propofol, thiopentone or ketamine) and sometimes a muscle relaxant
During induction patients move through the planes of anaesthesia, what are the 4?
- Analgesia and amnesia
- Delirium to unconsciousness
- Surgical anaesthesia
- Apnoea to death
What are some complications of induction?
- Anaphylaxis
- Regurgitation and aspiration
- Airway obstruction and hypoxia
- Laryngospasm
- Cardiovascular instability
- Cardiac arrest (rarely)
-
Awareness
- Reduce risk by using depth of anaesthesia monitors
- Eye injury
- Due to cornea drying out from lack of blinking
- Reduce risk by covering eyes or using eye lubricants
- Hypothermia
- Increases post-op pain, risk of infection, risk of bleeding
- Temperature is checked every 30 minutes
- Reduce risk by covering patient
- Pressure injury
- Reduce risk by not placing things in contact with patients skin
- Venous thromboembolism
- Reduce risk by keeping patients active before surgery, using TED stockings, chemical prophylaxis
- Nerve injury
- Nerves that run over bony prominence are most at risk
- Reduce risk by pressure point padding and careful positioning
How can the risk of the following be reduced:
- awareness
- eye injury
- hypothermia
- pressure injury
- venous thromboembolism
- nerve injury
- Awareness
- Reduce risk by using depth of anaesthesia monitors
- Eye injury
- Due to cornea drying out from lack of blinking
- Reduce risk by covering eyes or using eye lubricants
- Hypothermia
- Increases post-op pain, risk of infection, risk of bleeding
- Temperature is checked every 30 minutes
- Reduce risk by covering patient
- Pressure injury
- Reduce risk by not placing things in contact with patients skin
- Venous thromboembolism
- Reduce risk by keeping patients active before surgery, using TED stockings, chemical prophylaxis
- Nerve injury
- Nerves that run over bony prominence are most at risk
- Reduce risk by pressure point padding and careful positioning
Other than the administration of drugs to begin induction, what are some other important aspects?
- Airway management
- Anaesthesia causes loss of airway reflexes and relaxation of tissues
- Types of management includes
- Triple airway manoeuvre
- Anaesthetic mask
- Oropharyngeal airway – splints open airway and pushes tongue forwards, only sometimes used
- Laryngeal mask airway (LMA)
- Endotracheal tube (ETT)
- Indications for intubation
- Protection from aspiration
- Need for muscle relaxation for operation
- Shared airway (surgeon and anaesthetic working in same area)
- Need for tight CO2 control
- Minimal access to patient
- Breathing
- Spontaneous ventilation
- Controlled ventilation
- Supported ventilation
- Circulation
- Control of haemodynamics
- BP taken every 5 minutes
- Vasoactive drugs
- Control of haemodynamics
What are different types of management for the airway during induction?
- Triple airway manoeuvre
- Anaesthetic mask
- Oropharyngeal airway – splints open airway and pushes tongue forwards, only sometimes used
- Laryngeal mask airway (LMA)
- Endotracheal tube (ETT)
What does LMA stand for?
Laryngeal mask airway