Stage 2 Anesthesia: The Excitement/Delirium Phase
Stage 2 anesthesia, also known as the excitement or delirium stage, is a dangerous transitional period during induction and emergence from general anesthesia characterized by involuntary movements, irregular breathing, laryngospasm risk, and heightened airway reflexes—this stage must be traversed rapidly to minimize morbidity and mortality.
What is Stage 2 Anesthesia?
Stage 2 represents the period between loss of consciousness (end of Stage 1) and establishment of surgical anesthesia (Stage 3). This is a critical high-risk phase where:
- Consciousness is lost but reflexes are hyperactive and unpredictable
- The patient transitions from voluntary to involuntary control
- Airway reflexes are exaggerated and easily triggered
- The brain exhibits disinhibition with loss of cortical control before deeper centers are suppressed
Clinical Signs of Stage 2
Respiratory Changes
- Irregular, erratic breathing patterns
- Breath-holding episodes
- Coughing and gagging reflexes are heightened
- Laryngospasm risk is maximal during this stage
Motor Activity
- Involuntary movements of extremities
- Muscle rigidity or thrashing
- Jaw clenching
- Struggling or combative behavior
Autonomic Instability
- Tachycardia and hypertension
- Pupillary dilation
- Increased salivation and secretions
- Potential for vomiting with aspiration risk
Airway Responses
- Exaggerated gag and cough reflexes
- Laryngospasm (potentially life-threatening)
- Bronchospasm
- Breath-holding
When Does Stage 2 Occur?
Stage 2 occurs during two critical time periods:
1. During Induction
- Immediately after loss of consciousness
- Before adequate depth of anesthesia is achieved
- Goal: Pass through this stage as rapidly as possible
2. During Emergence
- As anesthetic depth lightens from Stage 3 back toward consciousness
- This is when most complications occur with airway devices 1
Stage 2 and the Laryngeal Mask Airway (LMA)
Critical Timing Considerations
The LMA should NEVER be inserted or removed during Stage 2 because:
- Airway reflexes are maximally sensitive to stimulation
- Laryngospasm risk is highest 1
- Coughing and gagging will prevent successful placement
- Patient movement makes insertion dangerous
Safe LMA Insertion Strategy
Insert the LMA only in Stage 3 (surgical anesthesia) when:
- Eyelash reflex is completely absent
- Jaw is relaxed
- Airway reflexes are suppressed
- Patient is adequately anesthetized 2
The evidence shows that adequate depth is typically achieved at 1-3 minutes after induction with propofol or sevoflurane 2. Any signs of coughing, gagging, or jaw tension indicate inadequate depth and require deepening anesthesia before attempting LMA insertion 3.
Safe LMA Removal Strategy
Two approaches exist, both designed to avoid Stage 2:
Option 1: Deep Extubation (Remove in Stage 3)
- Remove LMA while patient remains deeply anesthetized
- Adequate depth of anesthesia is critical to avoid laryngospasm 3
- Signs indicating inadequate depth: cough, gag, or changed breathing pattern 3
- If these occur: immediately deepen anesthesia before proceeding
- Risk: Upper airway obstruction (easily managed with jaw thrust) 1
- Benefit: Avoids coughing and airway irritation
Option 2: Awake Removal (Remove in Stage 1)
- Wait until patient is fully awake, eye-opening, and obeying commands 3
- Patient has passed completely through Stage 2 back to consciousness
- Risk: More coughing during removal 1
- Benefit: Patient can protect own airway
The evidence shows no clear superiority of one technique over the other for serious complications 1. The key principle is: NEVER remove the LMA during the transition through Stage 2.
Critical Pitfalls to Avoid
1. Attempting LMA Insertion Too Early
- Inserting before adequate anesthetic depth guarantees Stage 2 complications
- Wait for complete loss of eyelash reflex and jaw relaxation 2
- If insertion triggers coughing/gagging: remove, deepen anesthesia, wait
2. Removing LMA at Wrong Depth
- The "in-between" state (Stage 2) is most dangerous
- Commit to either deep removal OR fully awake removal
- Never remove when patient is "lightening" but not yet awake
3. Inadequate Monitoring During Emergence
- Stage 2 during emergence is unpredictable in timing
- Maintain continuous observation
- Have suction immediately available
- Be prepared to manage laryngospasm
4. Stimulating the Airway in Stage 2
- Suctioning, repositioning, or manipulating the LMA during Stage 2 can trigger catastrophic laryngospasm 1
- If patient shows signs of lightening (movement, irregular breathing): either deepen anesthesia or wait for full awakening
Minimizing Time in Stage 2
The fundamental principle: Traverse Stage 2 as rapidly as possible
During Induction:
- Use adequate induction doses
- Avoid underdosing which prolongs Stage 2
- Propofol 2-2.5 mg/kg or sevoflurane 8% provides rapid transition 2
During Emergence:
- Plan your emergence strategy in advance
- For deep extubation: maintain adequate volatile anesthetic concentration 3
- For awake extubation: allow complete emergence without intermediate manipulation
Special Populations:
- Children have heightened airway reflexes and shorter safe apnea times 1
- Laryngospasm and bronchospasm risks are 5 times greater with endotracheal tubes versus LMA in pediatric patients 1
- This makes proper Stage 2 management even more critical in children
The Bottom Line
Stage 2 anesthesia is an unavoidable but dangerous transition phase where airway reflexes are hyperactive and unpredictable. When using an LMA, your primary goal is to avoid any airway manipulation during Stage 2—insert only when deeply anesthetized in Stage 3, and remove either while still deep in Stage 3 or after the patient has fully emerged to Stage 1. The middle ground is where complications occur, particularly life-threatening laryngospasm. Meticulous attention to depth of anesthesia and recognition of Stage 2 signs are essential skills for safe airway management.