Device-Related Error in Patient-Controlled Analgesia

Analysis of 82,698 Patients in a Tertiary Hospital

Hyo-Jung Son, MD; Sung-Hoon Kim, MD, PhD; Jeong-Ok Ryu, RN, MS; Mi-Ra Kang, RN, MS; Myeong-Hee Kim, RN, MS; Jeong-Hun Suh, MD, PhD; Jai-Hyun Hwang, MD, PhD


Anesth Analg. 2019;129(3):720-725. 

In This Article

Abstract and Introduction


Background: Patient-controlled analgesia (PCA) is one of the most popular and effective methods for managing postoperative pain. Various types of continuous infusion pumps are available for the safe and accurate administration of analgesic drugs. Here we report the causes and clinical outcomes of device-related errors in PCA.

Methods: Clinical records from January 1, 2011 to December 31, 2014 were collected by acute pain service team nurses in a 2715-bed tertiary hospital. Devices for all types of PCA, including intravenous PCA, epidural PCA, and nerve block PCA, were included for analysis. The following 4 types of infusion pumps were used during the study period: elastomeric balloon infusers, carbon dioxide-driven infusers, semielectronic disposable pumps, and electronic programmable pumps. We categorized PCA device-related errors based on the error mechanism and clinical features.

Results: Among 82,698 surgical patients using PCA, 610 cases (0.74%) were reported as human error, and 155 cases (0.19%) of device-related errors were noted during the 4-year study period. The most common type of device-related error was underflow, which was observed in 47 cases (30.3%). The electronic programmable pump exhibited the high incidence of errors in PCA (70 of 15,052 patients; 0.47%; 95% confidence interval, 0.36–0.59) among the 4 types of devices, and 96 of 152 (63%) patients experienced some type of adverse outcome, ranging from minor symptoms to respiratory arrest.

Conclusions: The incidence of PCA device-related errors was <0.2% and significantly differed according to the infusion pump type. A total of 63% of patients with PCA device-related errors suffered from adverse clinical outcomes, with no mortality. Recent technological advances may contribute to reducing the incidence and severity of PCA errors. Nonetheless, the results of this study can be used to improve patient safety and ensure quality care.


Acute pain control is an important part of postoperative patient care, which is associated with promoting patient recovery, shortening hospital stay, and reducing medical costs.[1] Patient-controlled analgesia (PCA) is one of the most popular modalities of acute postoperative pain management. PCA is a method of analgesic administration in which an automatic infusion device controls the flow limit, thereby allowing patients to self-administer analgesics as per their requirement. PCA has proven its superiority over conventional nurse-controlled analgesia in decreasing postoperative pain.[2] It has also been proven to improve patient satisfaction, preserve good pulmonary function, and shorten hospital stay.[3] However, there is a high likelihood of medication errors, such as those in transcribing, prescribing, programming, dispensing, and monitoring, occurring at each stage.[4–6] Occasionally, ≥2 combined errors can lead to complex errors in PCA.[7] Most PCA involves opioid-based regimens. Therefore, errors in PCA are associated with a risk of opioid overdose and may cause serious adverse clinical outcomes.[7–9]

Many attempts to define and reduce PCA-associated medication errors have been made over a long period. Resources on PCA-related medication errors have divided the errors into 2 main categories: human factor-related errors and device-related errors. PCA device-related errors account for 79% of the total errors in intravenous PCA, and human factor-related errors account for 6.5% of them.[10] So far, studies have mostly focused on protection against human factor-related errors in PCA. Several types of safety intervention programs, including those involving purchasing easier-to-use PCA pumps, using a standardized PCA protocol, educating nurses, and implementing an independent double-check system policy, have been established to prevent human factor-related errors in PCA. Paul et al[8] reported that these patient safety interventions considerably improve and stabilize the safety of PCA administration. Relatively less research has been directed toward PCA device-related errors. However, there have been anecdotal case reports regarding PCA device malfunction associated with fatal morbidities that demanded emergent resuscitation.[11]

In this study, we assessed the incidence of PCA device-related errors according to the type of continuous infusion pump and described the characteristics of these errors and their clinical outcomes.