Early results of a double-blind, randomised, placebo-controlled trial show that intravenous ketorolac results in a “substantial reduction” in opioid use and improved pain control compared to placebo and intravenous acetaminophen. In addition, the investigators note a trend towards decreased length of stay with intravenous ketorolac, and no increase in rates of haematoma, drain output, transfusions or serum creatinine.
First author Sravisht Iyer (Hospital for Special Surgery, New York, USA) recently presented the study at the 26th International Meeting on Advanced Spine Techniques (IMAST 2019; 17–20 July, Amsterdam, The Netherlands), sponsored by the Scoliosis Research Society, at which it was announced as the winner of the Whitecloud Award for Best Clinical Paper. The research was supported by a North American Spine Society Research Grant.
The investigators found that intravenous ketorolac reduces opioid use after spine fusion by over 40% compared to placebo and over 30% compared to intravenous acetaminophen, as well as improved pain control, on postoperative day one after lumbar spinal fusion. Furthermore, alongside a trend toward decreased length of stay, they did not notice any increase in in-hospital complications. They remark that longer term follow-up will assess the impact of intravenous ketorolac on pseudoarthrosis.
Iyer and colleagues note that 115 patients met the inclusion criteria and were randomised to receive intravenous ketorolac (39 patients), intravenous acetaminophen (also 39 patients) groups, or placebo (37 patients). There was no difference between patients with regards to demographic or surgical variables.
The intravenous ketorolac group had “substantially lower” opioid use at 72 hours (181±156mg) compared to the intravenous acetaminophen patients (268±176mg) and those who received placebo treatment (315±183mg). Essentially, intravenous ketorolac was superior to both intravenous acetaminophen and the placebo, while intravenous acetaminophen was not superior to placebo treatment.
Similar trends were observed for opioid use per hour, and there were no differences in opioid related adverse events, drain output, haematocrit levels, serum creatinine, and transfusion rates.
Patients between the ages of 18 and 75, with lumbar fusion between levels one and two and no history of long-term opioid use were included in the study. Smokers and patients with contraindications to intravenous ketorolac or intravenous acetaminophen were excluded.
Intravenous ketorolac patients received either 15mg, if they were over the age of 65, or 30mg, if they were under 65 years old, every six hours for a total of 48 hours. Intravenous acetaminophen patients received 1,000mg every six hours and the placebo patients were also treated every six hours for 48 hours.
The authors note that lumbar spine fusions are rated among the most painful surgical procedures, and believe that “adequately controlling postoperative pain while minimising opioid use is an important public health objective.”
Talking to Spinal News International, Iyer remarks: “Opioid use following elective surgery contributes not insubstantially to the opioid epidemic. The early results of this double-blind randomised trial provide compelling evidence that the intravenous ketorolac can optimise postoperative pain control as part of a multimodal analgesic regimen.”
He continues: “It will be important to follow these patients over the longer term and ensure this limited postoperative dosing of ketorolac does not negatively impact fusion rates.”