Risk factors for opioid-induced respiratory depression and failure to rescue: a review.

PURPOSE OF REVIEW: The primary objective of this review is to identify the risk factors for opioid-induced respiratory depression (OIRD) in the postoperative period. RECENT FINDINGS: In the postoperative period, OIRD has often been reported resulting in morbidity and mortality. The risk factors which predispose surgical patients to increased risk of OIRD are not clearly defined. A literature search was performed for adult surgical patients who were prescribed opioids during their hospital stay and any available reports on postoperative respiratory depression/respiratory events. SUMMARY: Elderly, female sex, presence of obstructive sleep apnea, chronic obstructive pulmonary disease, cardiac disease, diabetes mellitus, hypertension, neurologic disease, renal disease, obesity, two or more comorbidities, opioid dependence, use of patient controlled analgesia, different routes of administration of opioids and concomitant administration of sedatives are significant risk factors for postoperative OIRD. The majority of patients with OIRD are deeply sedated and inadequately monitored. In patients with underlying risk factors, the dose of opioids should be carefully titrated. Enhanced monitoring of sedation level, respiratory rate, pulse oximetry and capnography is needed in the first 24 h after surgery.