Anesthesia Management

Introduction

Anesthesia management involves a comprehensive approach to patient care, including pharmacological interventions, intraoperative monitoring and management, and anesthesia techniques, as recommended by the American Society of Anesthesiologists and the European Society of Cardiology 1, 2, 3, 4

Low-dose ketamine (0.1-0.25 mg/kg) may be considered as an adjunct to counteract hypotension while providing analgesia, with caution for potential postoperative confusion in elderly patients, as recommended by the American Society of Anesthesiologists 3
Midazolam should be used cautiously and in reduced doses if sedation is required 3
Propofol is the most commonly used agent for induction and maintenance due to its rapid onset, short duration of action, and favorable recovery profile, but may cause more pronounced hypotension in hemodynamically challenged patients 2
Short-acting opioids such as remifentanil are typically used due to their rapid onset and offset 2
Agents like rocuronium or succinylcholine may be used as muscle relaxants with appropriate monitoring 5
Desflurane may offer faster wake-up times in patients with BMI ≥30 kg/m² 6
Nitrous oxide should be avoided due to increased risk of postoperative nausea and vomiting (PONV) and delayed return of bowel function 7

Invasive arterial blood pressure monitoring is strongly recommended 3
Central venous pressure monitoring should be considered in patients with significant cardiovascular comorbidities 3
Lower intra-abdominal pressures (8-10 mmHg) should be used if laparoscopic surgery is performed to minimize hypotension 8
Normothermia should be maintained to prevent worsening of hypotension 8
Standard monitoring, including ECG, SpO₂, and NIBP, is required for all anesthesia 5
Processed EEG monitoring is strongly recommended during TIVA with neuromuscular blockade to assess depth of anesthesia and prevent awareness 5
Quantitative neuromuscular monitoring is essential whenever neuromuscular blocking drugs are administered 5, 7

Simultaneous administration of spinal/epidural anesthesia with total intravenous anesthesia (TIVA) should be avoided due to the risk of precipitous falls in blood pressure, as recommended by the European Society of Cardiology 3, 4
If regional techniques are used as adjuncts, lower doses of local anesthetics and peripheral nerve blocks rather than neuraxial techniques should be considered 3
The American Society of Anesthesiologists recommends the use of continuous intravenous infusion of anesthetic agents for induction and maintenance of general anesthesia without the use of inhaled anesthetic gases, relying on carefully titrated IV medications to achieve hypnosis, analgesia, and when needed, muscle relaxation 1, 2
The American College of Surgeons recommends using short-acting inhalational agents, such as sevoflurane or desflurane, or total intravenous anesthesia (TIVA) for maintenance of general anesthesia 9
TIVA is associated with reduced postoperative nausea and vomiting compared to inhalational techniques 2

Patients should be evaluated for arterial saturation <95% on air, forced vital capacity <3L or FEV1 <1.5L, and respiratory wheeze at rest to assess respiratory function 10
A fasting period of 6-8 hours for solids is recommended to reduce the risk of aspiration 9
Aspiration prophylaxis should be considered, including proton pump inhibitors and non-particulate antacids 9
Patients should be evaluated for comorbidities, including nutritional status, cardiopulmonary status, coagulation profile, and airway assessment, before surgery 9
Cardiopulmonary exercise testing should be considered for high-risk patients 10

Patients with a Mallampati score 3-4, neck circumference ≥42 cm, thyromental distance <6 cm, intact dentition, age ≥46 years, and male gender are at higher risk for difficult airway management 6
Video laryngoscopy should be considered for anticipated difficult airways 6
Obese patients may require a 30° reverse Trendelenburg position with ramp elevation of head, neck, and shoulders to improve intubation conditions 11
High-flow nasal oxygen during induction can extend safe apnea time 6

Opioid-sparing techniques such as NSAIDs, paracetamol, lidocaine, dexmedetomidine, ketamine, or magnesium should be considered as adjuncts 6
Alternative regional techniques such as transversus abdominis plane (TAP) blocks, erector spinae plane blocks, and local anesthetic wound infiltration should be considered if epidural is contraindicated 6
The American Society of Regional Anesthesia and Pain Medicine strongly recommends mid-thoracic epidural (T7-T10) for open gastrectomy to optimize pain control and reduce opioid requirements 9, 7
Epidural analgesia should be inserted before induction and continued intraoperatively and for 48-72 hours postoperatively 9
Low-dose local anesthetic with short-acting opioid should be used for epidural analgesia 9
Multimodal analgesia, including intravenous patient-controlled analgesia (IV PCA) with opioid-sparing adjuncts, should be considered as an alternative if epidural analgesia is contraindicated 11

Patients should be extubated when fully awake with return of airway reflexes and positioned in a sitting position for extubation 10
The Difficult Airway Society extubation guidelines should be followed 10
Patients should be monitored for sleep-disordered breathing postoperatively 10
Early mobilization and removal of nasogastric tube are recommended to promote return of bowel function and reduce pulmonary complications 9
Chewing gum may be considered to stimulate bowel function and reduce the risk of ileus 9
Multimodal PONV prophylaxis, including dexamethasone and ondansetron, should be used based on patient risk factors 7
Incentive spirometry and early mobilization may be used to reduce the risk of atelectasis and pneumonia 9
Hypotension with epidural analgesia may be treated with vasopressors if normovolemic 9
Post-dural puncture headache may be reduced by using pencil-point needles for spinal techniques 12

Elderly patients may have reduced anesthetic requirements and be at higher risk of postoperative delirium, and bispectral index (BIS) monitoring may be considered 9
Patients with cardiovascular disease may be at higher risk of hypotension with epidural analgesia, and vasopressors should be used to treat hypotension if normovolemic 9
Target-controlled infusions in obese patients may require special consideration, as the Marsh and Schnider formulae become unreliable above 140-150kg 10
Lung-protective ventilation with low tidal volumes (6-8 ml/kg ideal body weight), PEEP 6-8 cmH₂O, and recruitment maneuvers to reduce atelectasis should be implemented 10
Normothermia should be maintained throughout the procedure to reduce the risk of hypothermia and hemodynamic instability 7
Goal-directed fluid therapy should be used to avoid fluid overload, and mean arterial pressure should be maintained with vasopressors once normovolemia is established 9