The management of obese patients undergoing surgery demands careful planning and knowledge of their unique physiological characteristics, particularly when prone positioning is necessary. While clinicians historically worried prone positioning would worsen cardiorespiratory problems due to abdominal weight, current research shows it can actually enhance lung function when the abdomen remains unrestricted.
In sedated and paralyzed obese patients, supine positioning reduces functional residual capacity (FRC) and causes atelectasis as abdominal fat pushes the diaphragm upward. Research demonstrated that repositioning from supine to prone increased FRC from 0.894 liters to 1.980 liters, with improved lung compliance and better arterial oxygenation through visceral unloading and alveolar recruitment.
Free abdominal movement is essential for these benefits. Specialized equipment like Jackson operating tables with chest and pelvic bolsters provides better abdominal space than standard tables. Hard rubber roll supports that do not ensure abdominal freedom decreased respiratory compliance and increased airway pressures in studies examining this difference.
For morbidly obese patients (BMI >40 kg/m²), transferring anesthetized patients to the operating table carries risks including pressure injuries and endotracheal tube displacement. Awake fiberoptic intubation followed by awake prone self-positioning before anesthesia may reduce these dangers. A documented case involved a 180 kg patient receiving topical anesthesia and minimal sedation for intubation, then self-positioning on the Jackson table before general anesthesia — allowing the patient to confirm comfort and safety of pressure points beforehand.
The surgical team must monitor prone-specific complications: ischemic optic neuropathy (linked to obesity, male sex, Wilson frame use, and high blood loss), brachial plexus injuries from arm abduction exceeding 90 degrees, and thigh compartment syndrome. Protective ventilation strategies — low tidal volumes, recruitment maneuvers, appropriate PEEP — should continue throughout. While 10 cmH₂O PEEP is common, some patients require higher levels for adequate ventilation distribution.