What is the recommended anesthesia regimen for patients undergoing surgery?

Recommended Anesthesia Regimen for Surgical Patients

The optimal anesthesia regimen depends on the surgical procedure and patient characteristics, but generally consists of rapid-onset, easily reversible agents with multimodal analgesia to minimize opioid use, combined with appropriate monitoring and regional techniques when feasible. 1

Core Anesthetic Approach

Preoperative Preparation

• Avoid long- or short-acting sedative premedication as it delays immediate postoperative recovery 1
• Provide antacid and analgesic premedication, particularly long-acting NSAIDs unless contraindicated 1
• Ensure preoperative carbohydrate loading: allow clear fluids up to 2 hours and solids up to 6 hours before induction 1
• Conduct preoperative team briefing to confirm appropriate equipment and personnel availability 1

Induction Strategy

For standard adult patients:

• Use propofol 1-2 mg/kg IV at 0.5 mg/kg/min for induction, avoiding rapid bolus which increases cardiorespiratory depression 2
• Alternatively, sevoflurane mask induction is appropriate, particularly in pediatric patients, providing rapid smooth induction with minimal airway irritation 3, 4
• Administer short-acting opioids (fentanyl 1-5 mcg/kg, alfentanil, or remifentanil infusion) for analgesia 5, 2
• Provide neuromuscular blockade with rocuronium 0.9-1.2 mg/kg or succinylcholine 1-2 mg/kg for rapid sequence induction in emergency cases 5

For elderly, debilitated, or ASA III-IV patients:

• Avoid rapid bolus administration entirely 2
• Reduce induction doses and administer slowly over 60 seconds to minimize hypotension and apnea 1, 2

Maintenance of Anesthesia

Choose between two primary approaches:

1. Inhalational maintenance:

   • Use sevoflurane or desflurane (fat-insoluble agents with faster onset/offset) 1, 5
   • Desflurane may allow faster return of airway reflexes, particularly in obese patients 1
   • Maintain with 60-70% nitrous oxide in oxygen 5, 2

2. Total intravenous anesthesia (TIVA):

   • Propofol infusion 100-200 mcg/kg/min for adults, with higher rates (150-200 mcg/kg/min) during first 10-15 minutes, then reduce by 30-50% 2
   • Pediatric patients require 200-300 mcg/kg/min initially, then 125-150 mcg/kg/min (younger children need higher rates) 2
   • TIVA particularly beneficial for patients at high PONV risk 5

Critical Monitoring Requirements

Depth of anesthesia monitoring:

• Use processed EEG (BIS monitoring) in patients >60 years to reduce postoperative delirium and hypotension 6
• Target BIS approximately 50 in elderly patients (versus deeper levels at BIS 35) to significantly reduce delirium 6
• Avoid burst suppression (BIS <30), which increases delirium risk in older patients 6, 5
• Monitor age-adjusted MAC closely in elderly to avoid hypotension 6

Neuromuscular monitoring:

• Maintain deep neuromuscular block during laparoscopic surgery to facilitate surgical access 5
• Use quantitative peripheral nerve monitoring to ensure adequate reversal before extubation 5
• Consider sugammadex for reversal of profound rocuronium blockade 5

Standard monitoring:

• ECG, pulse oximetry, non-invasive blood pressure, capnography, and temperature monitoring are mandatory 3
• Maintain normothermia >36°C using active warming devices and warmed IV fluids 1, 5

Regional Anesthesia Integration

Regional techniques should be prioritized when possible:

• Regional anesthesia is preferred over general anesthesia where feasible, though airway management planning remains mandatory 1
• For open surgery: mid-thoracic epidural blocks using local anesthetics and low-dose opioids provide superior analgesia and reduce stress response 1, 5
• For laparoscopic surgery: spinal analgesia or morphine PCA are alternatives to epidural 1
• Spinal anesthesia with low-dose techniques (hyperbaric prilocaine 2% or 2-chloroprocaine) is acceptable for day surgery using 25G pencil-point needles to minimize post-dural puncture headache (<1% incidence) 1
• Ultrasound guidance improves regional block success and reduces local anesthetic dose 1
• Calculate local anesthetic doses using lean body weight to avoid toxicity (maximum lidocaine 5 mg/kg, bupivacaine 2.5 mg/kg) 1, 3

Multimodal Analgesia Strategy

To minimize opioid requirements:

• Administer prophylactic oral long-acting NSAIDs preoperatively unless contraindicated 1
• Use regional blocks or local infiltration for procedure-specific analgesia 1, 5
• Consider intravenous lidocaine infusion or intraperitoneal local anesthetic administration 5
• Provide written discharge instructions for analgesic timing to prevent pain when blocks wear off 1

PONV Prevention

Implement multimodal prophylaxis:

• Use multimodal PONV prophylaxis in all patients with ≥2 risk factors undergoing major surgery 1
• TIVA with propofol reduces PONV compared to inhalational agents 5
• Administer prophylactic antiemetics based on patient risk factors (history of PONV, motion sickness, specific procedures like laparoscopy) 1
• Restrict IV fluids to ≤500 mL for spinal anesthesia to reduce urinary retention 1

Special Population Considerations

Obese patients:

• Assume all obese patients have sleep-disordered breathing and modify technique accordingly 6
• Use depth of anesthesia monitoring to limit anesthetic load 6
• Position in ramped position with tragus level with sternum during induction 1
• Recognize reduced safe apnea time and increased risk of rapid catastrophic airway complications 1
• Have experienced personnel present; patients with OS-MRS score >3 require consultant discussion 1

Cardiac surgery patients:

• Avoid high-dose opioid technique with propofol as primary agent due to hypotension risk 2
• When propofol is primary agent, maintain infusion ≥100 mcg/kg/min supplemented with continuous opioid 2
• When opioid is primary agent, propofol maintenance ≥50 mcg/kg/min with attention to ensuring amnesia 2

Laparoscopic surgery:

• Use low tidal volume ventilation (6-8 mL/kg predicted body weight) with PEEP ≥5 cm H₂O 5
• Adjust ventilation parameters in Trendelenburg position to reduce atelectasis 5
• Consider inspired oxygen >80% to decrease surgical site infection risk 5
• Maintain mean arterial pressure 60-65 mmHg and cardiac index ≥2.2 L/min/m² for adequate gut perfusion 5

Common Pitfalls to Avoid

• Never use rapid bolus induction in elderly or ASA III-IV patients due to severe cardiorespiratory depression risk 1, 2
• Do not use morphine indiscriminately for day surgery; prefer shorter-acting opioids and multimodal analgesia 1
• Avoid excessive anesthetic depth (BIS <30) in elderly patients as it increases delirium and hypotension 6, 5
• Do not perform nerve blocks simultaneously with IV lidocaine; wait at least 4 hours between techniques to avoid toxicity 3
• Never discharge patients with spinal anesthesia until return of S4-5 sensation, plantar flexion at baseline strength, and big toe proprioception 1
• Recognize that rescue techniques (supraglottic airways, cricothyroidotomy) have higher failure rates in obese patients 1