postoperative respiratory failure

Etiology

risk factors

• older age
• low preoperative oxygen saturation, subsumes
  • smoking
  • preexisting pulmonary disease
    • COPD, obstructive sleep apnea
    • obesity hypoventilation syndrome
  • hypercapnia
  • respiratory infection during the previous month
  • preoperative hemoglobin level <10 g/dL
  • chronic heart failure
  • poor health or functional dependence
  • low serum albumin
  • renal failure
  • upper abdominal or thoracic procedure
  • duration of surgery > 2-3 hours
  • emergency procedure
• obesity hypoventilation syndrome
• hypercapnia

Laboratory

• preoperative arterial blood gas in at risk patients
  • pO2
    • pCO2, hypercapnia is a risk factor
• serum albumin
• serum creatinine
• complete blood count (CBC)

Management

• preoperative prevention
  • preoperative inspiratory muscle training
  • smoking cessation at least one month prior to surgery
• postoperative prevention
  • early mobility
  • pain control
  • chest physiotherapy
  • more intensive alveolar recruitment strategy (moderate PEEP + recruiting maneuvers) with low tidal volumes for protective ventilation may reduce severity of pulmonary complications in patients with hypoxemia after cardiac surgery
  • MKSAP suggests sleeping with head of bed elevated may be acceptable if patient desaturates when sleeping supine but is asymptomatic when awake & upright
• not beneficial
  • no benefit for postoperative incentive spirometry after CABG or abdominal surgery
  • no benefit for incentive spirometry with or without deep breathing exercises
  • continuous positive airway pressure (CPAP) after abdominal surgery does not prevent pneumonia, reintubation, or death
  • no benefit for bronchoscopy to clear airway mucus vs other methods of chest physiotherapy for preventing postoperative atelectasis

More general terms

• postoperative complication
• respiratory failure