Objective: The objective of this study was to identify the underlying causes of respiratory-related critical events associated with intravenous patient-controlled analgesia (i.v. PCA).
Design: The design is an observation study of prospectively collected data.
Setting: An Acute Pain Service (APS) was established for the management of all patients receiving i.v. PCA therapy for pain management. As part of ongoing care, all respiratory-related critical events were documented and analyzed by staff members of the APS team.
Patients: All patients receiving i.v. PCA therapy through the APS during the period of May 1990 through October 1992 were enrolled in the study.
Interventions: Evaluation of all respiratory-related critical events was attempted to identify the underlying cause of the event and to determine if measures could be taken to prevent recurrence of similar events.
Outcome measures: Any clinical event that could have or did lead to adverse patient outcome was used as an outcome measure.
Results: A total of 3,785 patients received PCA therapy for a total of 11,521 patient care days. Fourteen critical events occurred, of which four led to increased patient care. There were eight programming errors (all involving misprogramming of the continuous infusion): three involved a family member activating the device, three were the result of an error in clinical judgment, and one involved a patient tampering with the device (one event involved more than one error). Of the four events that led to increased patient care, two involved a family member activating the device, one was the result of a programming error, and one was the result of an error in clinical judgment. All patients who experienced a critical event had an uneventful recovery.
Conclusions: Following review of the critical events, it was determined that the design of the PCA device contributed to the misprogramming errors and the device was removed from service. Changes in the training of physicians and nurses were instituted to avoid recurrence of other errors identified. The incidence of serious respiratory-related critical events was 0.1%. i.v. PCA therapy has the risk of potentially serious complications and requires constant physician and nursing care with an active quality assurance program.