Author: Michael Vlessides
Patient-controlled analgesia (PCA) with IV opioids has been a hallmark of postoperative care. Yet, in today’s world of multimodal analgesic approaches and enhanced recovery after surgery (ERAS) protocols, a team of Canadian researchers is questioning whether PCA should be replaced with as-needed opioid administration.
Their study showed that the as-needed approach reduces opioid consumption during the first 48 hours after surgery, a finding they believe will become more pronounced as providers become more educated about the potential benefits of as-needed opioid administration.
“Anecdotally, I found that when we gave patients oral opioids on a PRN basis, their pain management was the same as it was with the IV PCA, but with much greater potential for opioid-related side effects, as well as delayed hospital discharge and patient dissatisfaction.”
Anesthetic care was standardized throughout the perioperative period, and comprised premedication with 1,000 mg of acetaminophen, 600 mg of gabapentin, and 400 mg of celecoxib. In the intraoperative phase, all patients underwent spinal anesthesia with intrathecal opioids; upon prosthesis implantation, the surgeon infiltrated a periarticular solution of 40 mL of 0.5% bupivacaine plus 100 mL of normal saline.
Postoperatively, the participants were randomly assigned into one of the two postoperative care groups. “The IV PCA group received a 1-mg morphine equivalent bolus dose of hydromorphone, with a lockout interval of five minutes, no background infusion, and a maximum dose of 30 mg in four hours,” Dr. Siddiqui said.
Patients were followed for a total of 48 hours after surgery. The trial’s end points included:
As reported at the 2019 annual meeting of the Canadian Anesthesiologists’ Society (abstract 636776), use of IV PCA was not found to significantly reduce opioid consumption over the first 24 hours after surgery (16.5 vs. 30.0 mg). This difference reached significance at 48 hours, however, as patients in the as-needed group consumed a total of 32.5-mg median morphine equivalents, compared with 65.0 mg for their counterparts receiving IV PCA (P=0.046).
Despite these findings, no significant differences were found between the as-needed and PCA groups with respect to median overall hospital LOS (49.8 vs. 49.5 hours; P=0.63). Similarly, there was no difference in patient satisfaction scores, which was a median of 5 in each group (P=0.55).
Although the results of the study did not meet the researchers’ expectations, Dr. Siddiqui believed they will only continue to improve as staff become more accustomed to the change from PCA to as-needed opioids.
“There is quite a bit of literature showing that IV PCA is better because it gives patients control and improved their satisfaction,” he said. “As a result, more and more people were moving toward IV PCA. But in this day and age—when we are giving much more than just opioids for pain control—these patients may not require IV medications after surgery, especially if they haven’t undergone general anesthesia and can take oral medications when they need to.”
Nevertheless, the switch from PCA to as-needed medications after total knee arthroplasty represented a significant cultural shift at the hospital. “Initially, the expectation was that every patient would get IV PCA,” Dr. Siddiqui said in an interview with Anesthesiology News. “Indeed, when we looked at our results more closely, we saw that the first 20 or 25 patients in the study were not given their on-demand medications at the right time. Then, after we had done all the education sessions with all the nurses on the floor, it got better, and now we rarely use IV PCA for these fast-track patients.”
However, he recognized that proper education is the linchpin to the program’s success. “That is not just patient education, but also nursing and surgeon education as well,” Dr. Siddiqui said. “It’s important to have a protocol-based approach rather than everyone just doing it their own way. The bundle of care should be standardized.”
Use of PCA May Be Declining
For Shireen Ahmad, MD, a professor of anesthesiology and obstetrics and gynecology at Northwestern University’s Feinberg School of Medicine, in Chicago, the researchers’ move toward as-needed opioids is a natural byproduct of anesthesiologists’ move toward multimodal analgesic techniques. “I don’t think this type of program is unusual in this day and age, because we’re moving away from administering just opioids for pain management,” Dr. Ahmad said.
“We have implemented many enhanced recovery programs here, and we don’t routinely use PCA.”
Dr. Ahmad agreed that education is an important part of any such paradigm shift. “There is quite a bit of education and reinforcement that goes into it, with patients, nurses and physicians, because it represents a significant culture change for everyone, most of whom are used to giving the patient PCA and letting them administer according to their own needs,” she said.
Educational efforts notwithstanding, Dr. Ahmad believes the days of PCA opioids may be coming to an end. “It will be a long ways down the line, but I would like to think that we’re getting to the point where we recognize that we can use nonopioid medications in place of opioids, with far fewer side effects and far less problems with patients getting addicted to these medications,” she said. “I think we’re beginning to recognize these problems and are hopefully getting away from turning to opioids as our first drug of choice.”