General Anaesthesia: Correct Statement Analysis
Option D is correct: Rapid sequence induction of anaesthesia is a recognized technique for general anaesthesia, particularly in patients at increased risk of pulmonary aspiration. 1
Analysis of Each Option
Option A: The Triad of General Anaesthesia - INCORRECT
The classical triad of general anaesthesia consists of:
- Amnesia (unconsciousness)
- Analgesia (pain relief)
- Muscle relaxation (NOT "muscle anaesthesia") 2
The term "muscle anaesthesia" is not standard terminology. The correct component is muscle relaxation, which facilitates surgical access and prevents patient movement during procedures. 2
Option B: IV Access Prior to Induction - INCORRECT (Not Always Required)
While IV access is standard practice in most cases, it is not an absolute requirement in all circumstances:
- Inhalational induction can be performed without prior IV access, particularly in pediatric patients or those with difficult venous access 2
- IV access can be established after induction in selected cases, especially in children 3
- The statement "must always" makes this option incorrect, as clinical practice allows for exceptions based on patient factors and clinical judgment 2
Option C: Nitrous Oxide Properties - INCORRECT
This statement contains a significant error regarding post-operative nausea and vomiting (PONV):
- While nitrous oxide does have analgesic properties, it is associated with increased risk of PONV, not low risk 1
- Inhalational anaesthetics, including nitrous oxide, are known to be emetogenic 1
- Guidelines specifically recommend avoiding nitrous oxide in certain contexts (e.g., obstetric labour analgesia during COVID-19) due to various concerns 1
Option D: Rapid Sequence Induction - CORRECT
Rapid sequence induction (RSI) is a well-established, specific technique for anaesthesia induction in patients with increased aspiration risk. 1
Key Components of RSI:
Indications: Patients with no 2-hour liquid or 6-hour food fasting, acute vomiting, ileus, absent protective reflexes, gastrointestinal disorders, or pregnant women after the 3rd trimester 4
Technique goals: Fast achievement of deep anaesthesia and muscle relaxation to avoid coughing and choking, with rapid airway protection via endotracheal intubation 5, 4, 6
Drug selection: Combination of opioid, hypnotic (propofol, thiopental, etomidate, or ketamine), and muscle relaxant (rocuronium 1.0-1.2 mg/kg or succinylcholine 1.0 mg/kg) 5, 4
Modern modifications: The classical RSI concept has evolved; modified RSI may include gentle mask ventilation or CPAP after loss of consciousness to prevent hypoxia, particularly in high-risk patients 1, 7
Critical Clinical Pitfalls
Cricoid pressure, once considered a cornerstone of RSI since 1961, has lost importance after controversial discussions and is no longer universally recommended. 5 Modern guidelines prioritize preventing hypoxia over theoretical aspiration risk when managing the airway. 7
Pre-oxygenation for 3-5 minutes with FiO2 of 1.0 is essential to maximize safe apnea time during RSI. 7, 4