The management of postsurgical pain with patient-controlled analgesia pumps may be safe, as indicated by a low rate of device-related error, according to results from a retrospective study published in Anesthesia & Analgesia.
Patient-controlled analgesia infusion pumps are generally considered safe and effective for postoperative pain management but may be associated with human- and device-related errors, which can represent serious risks when opioid analgesics are delivered.
Inpatient records from a 4-year period at a tertiary hospital were retrospectively analyzed to determine error rates associated with intravenous, epidural, and nerve block patient-controlled analgesia using elastomeric balloon infusers, carbon dioxide-driven infusers, semielectronic disposable pumps, or electronic programmable pumps. Device-related errors were categorized according to mechanism of error and related clinical outcomes.
Analysis of records from 82,698 patients who underwent surgery indicated that 0.74% (n=610) and 0.19% (n=155) of pump-associated errors were attributed to human- and device-related issues, respectively. Of the device-related errors, there were 78 cases (50.3%) of underflow, making this the most common issue. Overflows, display errors, and broken pumps were to blame in 18.1%, 23.2%, and 8.4% of device-related cases, respectively.
The highest rate of patient-controlled analgesia device errors occurred in electronic programmable pumps (70 of 15,052; 0.47%; 95% CI, 0.36%-0.59%), followed by semielectronic pumps (56 of 34,312; 0.16%; 95% CI, 0.12%-0.21%), carbon dioxide-driven infusers (20 of 18,709; 0.11%; 95% CI, 0.07%-0.17%), and balloon infusers (9 of 14,625; 0.06%; 95% CI, 0.03%-0.12%).
Among patients who experienced device-related errors, 63.2% had an adverse event, ranging from mild to severe, with no deaths recorded (inadequate analgesia, 56.6%, opioid overdose symptoms, 6.5% [70% of which caused by overflow], major physiologic changes, 5.8%).
Study limitations include possible exclusion of defective pumps from analysis, lack of causality information, and failure to account for possible confounders.
Underflow was the most frequent device error; however, overflow carried more risks inherent with opioid analgesics. In attempting to balance these considerations, the authors noted, “Underflow errors should be considered as seriously as overflow errors. Taken together, effective postoperative pain management requires a balance between safety issues, mainly from overflow, and satisfaction issues, mainly from underflow.”
Son H-J, Kim S-H, Ryu J-O, et al. Device-related error in patient-controlled analgesia: analysis of 82,698 patients in a tertiary hospital [published online April 23, 2018]. Anesth Analg. doi:10.1213/ane.0000000000003397