What is the anesthetic plan for a 70-year-old female (F) with hypertension and obesity, currently on irbesartan (Angiotensin II receptor antagonist), atorvastatin (HMG-CoA reductase inhibitor), and spironolactone (aldosterone antagonist), undergoing a right laparoscopic hemicolectomy for a well-defined right neuroendocrine carcinoma of the small bowel with regional metastatic lymphadenopathy?

Anesthetic Plan for Obese Elderly Patient Undergoing Laparoscopic Hemicolectomy

A comprehensive anesthetic plan for this patient should include general anesthesia with endotracheal intubation, multimodal analgesia, careful fluid management, and postoperative admission to hospital for monitoring due to her multiple risk factors including advanced age, morbid obesity, and metastatic cancer.

Preoperative Assessment and Optimization

• Airway evaluation: Assess for predictors of difficult airway (neck circumference >43cm, Mallampati score, limited mouth opening) 1
• Cardiovascular assessment: Evaluate hypertension control on irbesartan and spironolactone
• Respiratory assessment: Screen for undiagnosed sleep-disordered breathing (assume presence given BMI 54) 2
• Laboratory tests: Complete blood count, renal function (especially with spironolactone use), electrolytes
• Medication management:
  • Continue irbesartan and spironolactone on the day of surgery
  • Continue atorvastatin
  • Administer prophylactic antibiotics 30-60 minutes before surgery 2

Intraoperative Management

Anesthetic Technique

• General anesthesia with endotracheal intubation is the technique of choice given:
  • Morbid obesity (BMI 54)
  • Advanced age (70 years)
  • Laparoscopic procedure with potential conversion to open 2

Airway Management

• Position patient in ramped position with tragus of ear level with sternum 2
• Preoxygenate thoroughly with PEEP to maximize safe apnea time 2
• Have difficult airway equipment immediately available
• Secure airway with appropriately sized endotracheal tube (based on ideal body weight) 2

Induction

• Short-acting agents based on lean body weight 2:
  • Propofol for induction
  • Rocuronium for muscle relaxation (with sugammadex immediately available) 2
  • Consider depth of anesthesia monitoring (BIS) 2

Maintenance

• Desflurane or sevoflurane (preferable to isoflurane due to faster offset in obese patients) 2, 1
• Consider total intravenous anesthesia (TIVA) if high risk for PONV 2
• Maintain deep neuromuscular blockade to facilitate surgical access 2
• Use neuromuscular monitoring to guide dosing and ensure complete reversal 2

Ventilation Strategy

• Pressure-controlled ventilation with:
  • Low tidal volumes (6-8 mL/kg ideal body weight) 1
  • PEEP (10 cmH₂O) 1
  • Recruitment maneuvers to reduce atelectasis 2
  • Head-up position (slight reverse Trendelenburg) when possible 2

Fluid Management

• Individualized goal-directed fluid therapy using flow measurements to optimize cardiac output 2
• Use balanced crystalloids rather than 0.9% saline 2
• Consider vasopressors for management of hypotension once normovolemia is established 2

Multimodal Analgesia

• Implement opioid-sparing techniques 3, 4, 5, 6, 7:
  • Acetaminophen (scheduled)
  • NSAIDs (if no contraindications)
  • Dexamethasone (serves dual purpose for PONV prophylaxis)
  • Local anesthetic infiltration at incision sites
  • Consider TAP block or wound catheter
  • Minimal use of long-acting opioids

PONV Prophylaxis

• Multimodal approach for this high-risk patient (female, non-smoker, abdominal surgery) 2:
  • Dexamethasone at induction
  • Ondansetron near end of case
  • Consider additional agents (e.g., scopolamine) if history of PONV

Emergence and Extubation

• Follow Difficult Airway Society extubation guidelines 2
• Ensure complete reversal of neuromuscular blockade with quantitative monitoring 2
• Extubate when fully awake in semi-sitting position 2, 1
• Maintain head-up position throughout recovery 2

Postoperative Management and Hospital Admission

This patient requires hospital admission postoperatively for several reasons:

1. Advanced age (70 years) - Increased risk of postoperative complications 2
2. Morbid obesity (BMI 54) - Risk of respiratory complications, especially with undiagnosed sleep-disordered breathing 2, 1
3. Metastatic cancer - Increased risk of complications and need for specialized care
4. Major abdominal surgery - Need for close monitoring of fluid status, pain control, and early detection of complications
5. Potential conversion to open procedure - Would require more intensive postoperative monitoring

Postoperative Care Plan

• Continue multimodal analgesia with opioid-sparing techniques 3, 6
• Monitor oxygen saturation continuously until mobile 2, 1
• Maintain head-up position to optimize respiratory mechanics 1
• Early mobilization to reduce risk of venous thromboembolism 2, 1
• Consider level 2 care if requiring long-acting opioids 2
• VTE prophylaxis with LMWH and compression stockings 2
• Early removal of urinary catheter (1-2 days) unless contraindicated 2

Common Pitfalls and Caveats

• Avoid assuming hypoxemia is solely due to obesity 1
• Do not rely solely on oxygen therapy without addressing underlying causes 1
• Avoid underestimating VTE risk in this high-risk patient 1
• Ensure adequate IV access (two sites recommended) due to potentially difficult vascular access 2, 1
• Monitor incision sites closely for signs of infection due to increased risk in obesity 1