What is the primary anesthetic goal during the preoperative and induction phase for a child undergoing elective bilateral strabismus surgery?

Primary Anesthetic Goal for Pediatric Strabismus Surgery

The primary anesthetic goal during the preoperative and induction phase is to minimize aspiration risk through appropriate fasting while reducing preoperative anxiety and distress, followed by smooth induction that prevents the oculocardiac reflex and postoperative nausea and vomiting.

Preoperative Phase Goals

Fasting Management

• Clear fluids should be allowed until 1 hour preoperatively 1, 2
• A 1-hour clear fluid fasting rule results in mean fasting times of approximately 3 hours in practice, which is safe and reduces child distress 1
• The traditional 2-hour rule translates into actual fasting durations of 6-13 hours due to parental anxiety and scheduling unpredictability, causing unnecessary distress 1
• Breast milk should be allowed until 2-4 hours preoperatively 2
• Solids should be restricted for 6 hours preoperatively 1
• Aspiration risk remains extremely low (3 per 10,000 cases) regardless of whether 2-hour, 1-hour, or ad lib clear fluid policies are followed 1

Psychological Preparation

• Preschool children undergoing strabismus surgery fear mutilation, abandonment, and separation from parents 1
• The cardiac catheterization laboratory environment (which resembles the operating room with masked physicians and monitors) is familiar to children from television and may trigger anxiety 1
• Comprehensive coping-skills training including controlled breathing, progressive muscle relaxation, and guided imagery reduces stress-related behaviors during and after hospitalization 1

Preoperative Assessment Priorities

• Screen for associated neuromuscular disorders, congenital syndromes, or cardiac disease, as these commonly occur in strabismus patients 3
• Malignant hyperthermia is no longer considered a specific concern associated with strabismus surgery 3
• Document any history of previous postoperative nausea and vomiting, as this is a major risk factor 3

Induction Phase Goals

Primary Induction Objectives

• Achieve smooth, rapid induction to minimize anxiety and facilitate airway management 4, 3
• Prevent triggering of the oculocardiac reflex during manipulation 3, 5
• Establish conditions that minimize postoperative nausea and vomiting risk 3, 6

Optimal Induction Technique

• Propofol-based total intravenous anesthesia (TIVA) is superior to inhalational induction for reducing postoperative nausea and vomiting 6
• Propofol 6 mg/kg over 60 seconds with fentanyl 2 mcg/kg provides better quality induction with less injection pain compared to propofol 3 mg/kg over 20 seconds 4
• The slower propofol induction (6 mg/kg over 60 seconds) also results in better maintenance quality with less bradycardia from oculocardiac reflex and reduced postoperative nausea and vomiting 4

Airway Management

• The laryngeal mask airway is used frequently and demonstrates a low incidence of complications in strabismus surgery 3
• This avoids the distress and potential complications of endotracheal intubation when appropriate 3

Oculocardiac Reflex Prevention

• The oculocardiac reflex is triggered in approximately 53% of pediatric strabismus cases, making it the most frequent intraoperative complication 5
• Children older than 6 years experience oculocardiac reflex more frequently than younger children 5
• Peribulbar block combined with general anesthesia significantly reduces both the incidence and severity of oculocardiac reflex compared to general anesthesia alone 7
• The use of prophylactic anticholinergics remains debatable and is not universally recommended 3

Common Pitfalls to Avoid

• Do not enforce rigid 2-hour clear fluid fasting rules, as this translates to excessive actual fasting times (6-13 hours) causing unnecessary distress, irritability, hypotension on induction, and increased postoperative nausea and vomiting 1
• Do not assume all children tolerate the same induction technique—slower propofol administration (60 seconds vs 20 seconds) significantly reduces injection pain and improves overall quality 4
• Do not rely solely on general anesthesia without considering regional techniques—peribulbar blocks reduce both oculocardiac reflex and postoperative nausea and vomiting 7
• Do not overlook the psychological preparation phase—children undergoing strabismus surgery experience significant anxiety related to separation, the unfamiliar environment, and fear of bodily harm 1