Postoperative opioids and risk of respiratory depression - A cross-sectional evaluation of routines for administration and monitoring in a tertiary hospital

Abstract

Objectives: Opioids are the most potent analgesics in the treatment of postoperative pain. Respiratory depression is, however, a serious side effect. The aims of this study were to evaluate current practice and routines for post-operative administration of opioids in a Norwegian university hospital and to evaluate whether the clinical safeguards adequately protected patients' safety regarding risk of respiratory depression.

Methods: The study had a retrospective cross-sectional design and included 200 patients, treated with opioids postoperatively. The patients were treated in a post-anesthesia care unit (PACU) before transferal to a surgical ward. Relevant data such as opioid dosages, routes of administration, sedation and respiratory function, routines for patient monitoring, and numbers of patients with opioid induced respiratory depression was collected.

Results: Two patients (1%) developed respiratory depression that needed naloxone to reverse the effect, and 32 patients (16%) had a respiratory rate (RR) <10/min, which may have been caused by opioids. In the PACU, the patient's RR was evaluated on a routine base, but after transferal to a surgical ward RR documented in only 7% of the patients.

Conclusions: The lack of routines for patient monitoring, especially RR, represented a risk of not detecting opioid induced respiratory depression.

Keywords: clinical monitoring; opioids; pain treatment; post-operative; respiratory depression; tertiary hospital setting.