In a nutshell, patient-controlled analgesia (PCA) provides superior postoperative analgesia and improved patient satisfaction compared to traditional PRN analgesic regimens because the person feeling the pain is in control, and they FEEL in control.
Every individual is unique when it comes to pain tolerance, analgesic needs, and drug pharmacokinetics and metabolism. This makes it difficult for an outsider to predict when a patient will need more analgesia. Coupled with administrative delays, traditional PRN analgesic regimens are more likely to provide inadequate postoperative analgesia. PCA analgesia circumvents these limitations by giving patients some degree of control over their analgesia.
While it is unclear if PCA use provides economic benefits, it is associated with greater patient satisfaction, which has become an important quality measure in today’s health care system. PCA has NOT been shown to improve hospital length of stay, but it does require less nursing time than frequently having to administer PRN medications.
Of course, the medical practitioner must determine the proper bolus dose, lockout, and background infusion rates to minimize the risk of overdose and respiratory depression. Risk factors include the use of a background infusion, advanced age, concomitant administration of sedative or hypnotic agents, and coexisting pulmonary disease or sleep apnea. As with any human-controlled system, there is always a risk for errors in programming or administration (operator error). However, the overall incidence of respiratory depression with PCA use is comparable to PRN systemic/neuraxial opioids.
Defined by: Roy Luo, MD