2.17 Pickwickian Syndrome

Pulmonary system review for the USMLE Step 1 Exam

• Pickwickian Syndrome is also called obesity hypoventilation syndrome
• Characterized by daytime hypoventilation leading to hypercapnia
• Often occurs in individuals with a BMI over 30
• Excess fat puts pressure on lungs and reduces ability to fully inflate
• Reduction in ventilatory drive may also cause hypercapnia
• Typical patient presents with obesity, daytime sleepiness, and symptoms consistent with obstructive sleep apnea
• Diagnosis confirmed by arterial blood gas
• Short term treatment with positive airway pressure therapy
• Long term treatment involves lifestyle changes to lose weight
• CPAP machine supplies positive pressure to reduce CO2 build up
• Weight loss relieves symptoms by reducing excess weight on lungs.