Patient-controlled analgesia typically consists of opioids or local anesthetics, but it may also include non-opioid analgesics or other medications.
Patient-controlled analgesia (PCA) is a method of analgesic delivery in which a predetermined dose of an analgesic medication is self-administered by the patient to manage pain.1 Dosing analgesics in this way has been shown to have more advantages than disadvantages compared with traditional dosing strategies.
Although PCA policies may differ among hospitals, there are basic principles of a fixed demand dose, lockout interval, background infusion rate, and time-based limit that must considered in order to provide safe, optimal patient care.2 The fixed demand dose is a predetermined dose of the analgesic that the patient self-administers with the push of a button. To avoid a medication overdose, a lockout interval is set.
During this interval, the dose cannot be administered until a pre-set time after the demand dose, even if the button is pushed. Some forms of PCA include a background infusion rate, which is a continuous infusion of any analgesics that the patient has been receiving, in addition to any of the demand doses that were ordered for the patient. Time-based limits also exist to put a cap on the amount of medication that a patient can receive in a certain period, whether in between demand doses or over longer periods, such as 1 or 4 hours.2
PCA typically consists of opioids or local anesthetics, but it may also include non-opioid analgesics or other medications. These medications can be administered to patients via different routes, such as intravenous, transdermal, or epidural or peripheral nerve catheter.2
An example PCA order could be as follows: “morphine: 2 mg demand dose, 10-minute lockout interval, with a background infusion rate of 1 mg/hr.” Based on this example, a patient who requested a demand dose of morphine every 10 minutes would receive a minimum dose of 1 mg of morphine every hour and a maximum dose of 13 mg of morphine every hour.
PCA has been shown to have many benefits, ranging from improved patient outcomes to lessening the burden on the nursing staff.3,4 By incorporating PCA, nurses have a slightly decreased workload because the analgesics are being administered solely by the pump, instead of manually.
The time that it would take for a nurse to retrieve the medication, administer the medication, and document the interaction could be used on other meaningful tasks, if PCA is utilized more frequently. In turn, the decreased burden can lead to more positive outcomes, such as increased nurse satisfaction, which can further improve patient care.3
Another benefit of using PCA is that, in some instances, it can lead to better pain control. It has even been demonstrated that using a PCA pump for pain management may be more effective than nurse-administered injections.3 Using a PCA pump allows for more standard dosing times, leading to more constant control of a patient's pain, while also minimizing other factors that may increase the potential for errors.
With the PCA pump, there will be fewer instances of underdosing or overdosing. From a pharmacy standpoint, PCA dosing also lessens the burden on pharmacists and pharmacy technicians because there would be less of a time burden to ensure that each dose the patient needs is delivered to the appropriate nurse or unit as separate orders.
The pharmacy would only have to prepare the PCA pump once, rather than preparing several single-dose regimens. PCA also leads to fewer chances for drug diversion or drug loss, since only the PCA itself is needed, not multiple doses in various syringes or containers.
PCA is considered a cornerstone of postoperative pain management in many institutions; however, there is some risk for complications. According to the patient-controlled analgesia and postoperative pressure ulcer study, patients utilizing PCA who underwent surgery, notably cesarean sections, developed more postoperative pressure ulcers than other patients studied.5
Special precautions should be taken in patients who have had a cesarean section or may be at an increased risk for pressure ulcers, such as bed-bound patients.5 The most commonly observed adverse effects (AEs) associated with PCA are nausea, vomiting, pruritus, respiratory depression, sedation, and urinary retention.6
However, these AEs are not limited to PCA and can also be seen with traditional dosing methods of opioids or other pain medications. Despite the risks, PCA is still considered a safe and effective method of acute pain management resulting from labor, trauma, or other medical conditions.7 PCA has shown to have more benefits overall as opposed to more traditional pain management strategies.
As hospitals continue to be understaffed, PCA has the ability to lessen the burden on both the nursing and pharmacy staff, while at the same time providing safe pain control strategies for patients by reducing medication errors. Patients using PCA have been found to have better pain relief without an increase in AEs compared to those using traditional analgesic administration, as evidenced by multiple studies.
Ultimately, both patients and health care providers may favor PCA administration methods over traditional analgesia administration.