J. J. Blank1, N. G. Berger1, J. P. Dux1, F. Ali1, K. A. Ludwig2, C. Y. Peterson2 1Medical College Of Wisconsin,General Surgery,Milwaukee, WI, USA 2Medical College Of Wisconsin,General Surgery, Colorectal Division,Milwaukee, WI, USA
Introduction: Pain management after surgery relies heavily on opioids despite known adverse effects. While opioid medications are typically the cornerstone of any pain control plan, they come at a cost. Opioids have a profound impact on postoperative gastrointestinal (GI) motility via activation of the mu-opioid receptors of the small and large intestines. Slowed gastrointestinal motility not only causes discomfort and pain, it causes nausea as well. In fact, opioid medications have been shown to increase the incidence of postoperative ileus, a disruption in normal intestinal peristalsis, which can result in longer hospital stays, increased incidence of complications, and decreased patient satisfaction. Additionally, according to the American Society of Addiction Medicine, four of five new heroin users started out misusing prescription pain medications. Therefore, a multi-modal strategy for pain management is optimal. There is limited data on the effectiveness of intravenous acetaminophen in comparison to other non-opioid analgesics after abdominal surgery.
Methods: PubMed, Scopus and Cochrane databases were queried for keywords acetaminophen, intravenous (IV), and postoperative. Included studies were prospective, had a comparison group receiving alternate medication, used IV acetaminophen for at least 24 hours, and evaluated adult patients having any trans-abdominal intraperitoneal surgery. Outcomes evaluated were study quality, demographic data, surgical technique, postoperative pain scores, and postoperative narcotic consumption. A random effect analysis of mean differences (MD) was performed and heterogeneity was assessed using I2 statistic.
Results: Seventeen articles were identified with 1,595 patients included. Overall study quality was moderate (mean Jadad score = 5.6 [±1.9], range 0-8). There was no difference in 24H pain scores or narcotic consumption between acetaminophen or any alternative analgesics (MD -0.10[-0.33, 0.14], p=0.42, I2=91%; MD -3.93[-9.12, 1.25], p=0.14, I2=99%, respectively). Subgroup analysis showed reduced 24H narcotic consumption for NSAIDs compared to acetaminophen (MD 11.18 [10.40, 11.96], p<0.001, I2=0%). For open surgery, analysis demonstrated reduced 24H narcotic consumption for acetaminophen compared to alternative medications (MD -7.29[-13.41, -1.16], p=0.02, I2= 99%). There were no differences in 24H pain scores among subgroups.
Conclusion: Both NSAIDs and acetaminophen show benefit in reducing 24-hour narcotic consumption in patients undergoing abdominal surgery with moderate quality evidence and significant heterogeneity amongst studies. Given the current nationwide opioid addiction crisis, there is great need to investigate alternative methods of pain control, such as NSAIDs and acetaminophen, in the postoperative setting.