anaesthetic complications Flashcards
(20 cards)
What are common complications encountered under general anaesthesia (GA)?
- Hypotension
- Hypoventilation
- Hypoxia
- Hypothermia
- Arrhythmias
- Myopathies/neuropathies
- Hyperthermia
- Regurgitation/vomiting
- Poor recoveries (equine)
- Respiratory arrest → cardiac arrest
- Miscellaneous/unknown
What is the normal awake systolic arterial pressure (SAP) range?
125-160 mmHg
What MAP value requires intervention during anaesthesia?
MAP <60-65 mmHg; SAP <90 mmHg
What factors can cause hypotension during anaesthesia?
- Drug induced
- Equipment errors
- Mechanical factors
- Patient factors
- Cardiac issues
- Respiratory issues
- Allergic reactions
What is the treatment approach for hypotension in anaesthesia?
- Assess anaesthetic depth
- IV fluid therapy
- Pharmacological intervention
- Stimulation of cardiovascular system
What is hypoventilation?
Reduced movement of gases in and out of alveoli due to various factors including anaesthetic agents and body positioning
What is hypercapnia and how is it measured?
Direct result of hypoventilation; measured by monitoring ETCO2 and/or arterial blood gas analysis
What is the normal range for ETCO2?
35-45 mmHg
What defines hypoxaemia?
PaO2 < 60 mmHg
What is the alveolar gas equation?
PAO2 = FiO2 (PB-PH2O) - PaCO2 / R
What are the phases of heat loss during anaesthesia?
- Phase 1: Initial rapid decrease in core temperature
- Phase 2: Slow, linear reduction due to heat loss exceeding production
- Phase 3: Plateau where loss equals production
What are the consequences of perioperative hypothermia?
- Impaired cardiovascular function
- Hypoventilation/hypoxia
- Decreased metabolism and detoxification
- Increased risk of surgical wound infection
How can hypothermia be prevented during anaesthesia?
- Pre-warming before anaesthesia
- Insulation on surgery table
- Using warm lavage fluids
- Active core rewarming
What is malignant hyperthermia and what are its symptoms?
- Rarely seen as primary entity
- Symptoms: Increased temperature, increased respiratory rate, metabolic acidosis, tachycardia, hypertension
What are the types of arrhythmias encountered in anaesthesia?
- Supraventricular arrhythmias
- Ventricular arrhythmias
What are the warning signs of cardiopulmonary arrest?
- Gradually increasing or decreasing heart rate
- Irregular or gasping breathing patterns
- Gradually decreasing ETCO2
What is regurgitation in the context of anaesthesia?
Movement of fluid from the stomach or duodenum into the oropharynx
What are common risk factors for regurgitation during anaesthesia?
- Species and breed
- History of reflux
- Pre-existing gastrointestinal disease
- Age
- Time under GA
- Surgical procedures
What minimum heart rate (HR) requires intervention during anaesthesia?
HR < 60 bpm
What factors contribute to ‘high risk’ anaesthetics?
- Age
- ASA classification
- Breed
- Certain drugs
- Anaesthetic type
- Length of procedure
- Experience of staff
