Acetaminophen Effective in Both Pill and IV Form Following Total Hip Arthroplasty

Among patients recovering after hip replacement surgery, the use of acetaminophen (Tylenol) either intravenously or in a pill form is equally effective at managing pain, according to researchers from the Hospital for Special Surgery (HSS) in New York City.

The research paper, titled “IV vs Oral Acetaminophen as a Component of Multimodal Analgesia After Total Hip Arthroplasty: A Randomized, Double Blinded, Controlled Trial,” was presented this week at the American Academy of Orthopaedic Surgeons (AAOS) Annual Meeting in Las Vegas. While postoperative pain management plans often involve the use of narcotic medication, the opioid epidemic has prompted researchers to investigate new methods to mitigate their use.

“A multifaceted pain management plan is standard for all patients having joint replacement surgery at HSS,” explained Dr. Geoffrey Westrich, the Director of Research for the Adult Reconstruction and Joint Replacement Service at HSS, in a press release. “Known as ‘multimodal analgesia,’ it entails the use of several different anesthetic agents and medications both during and after surgery to control pain and reduce side effects.”

Equal Efficacy

In this randomized, controlled study, researchers recruited 154 patients who underwent hip replacement surgery at HSS. All participants received the standard multifaceted pain control protocol subsequent to surgery and were arbitrarily assigned to one of two groups, one that received intravenous acetaminophen, while the other group was administered the oral pill form. Neither the patients nor their physicians were privy to which individuals were medicating with the intravenous versus oral acetaminophen. Moreover, both groups were provided with placebos, in IV form for the oral pill group and in pill form for the intravenous group.

At the initiation of the study, the researchers surmised that the intravenous form of acetaminophen might provide increased pain management over with the pill form, given that the IV reaches the blood stream quicker. However, the study results suggest that both performed equally well.

“Patients in both groups had low pain scores with activity, minimal opioid-related side effects, and limited opioid usage,” stated Dr. Westrich. “The big picture highlights multimodal analgesia overall as an effective method of pain control after joint replacement surgery.”

Another study co-author said that more research is still needed.

“How to optimize multimodal therapy for a given patient remains a ‘Holy Grail’ of research for this field,” remarked Dr. Jacques YaDeau, an anesthesiologist at HSS and one of the study’s authors. “At HSS, there is ongoing research on this topic, including both randomized trials and ‘big-data’ analysis.”