A prospective randomized study to analyze the efficacy of balanced pre-emptive analgesia in spine surgery

Background Context

Surgical procedures involving the spine are known to cause moderate to severe postoperative pain. Inadequate management of acute pain in the postoperative period results in higher morbidity, and consequently may lead to chronic pain caused by central sensitization. The role of pre-emptive analgesia (PA) and intraoperative analgesia in management of postoperative pain has gained precedence over recent years. Pathophysiology of postoperative pain in spine surgery is unique, as it is a combination of nociceptive, inflammatory, and neuronal stimuli. Blockage of all three stimuli in the perioperative period by pre-emptively administrating a combination of paracetamol (P), ketorolac (K), and pregabalin (PR) might help in adequate management and alleviation of acute postoperative pain.

Purpose

To evaluate the analgesic effect of a combination of P, K, and PR as pre-emptive multimodal analgesia, aimed to block or reduce acute postoperative pain after spine surgery.

Study Design

A prospective, randomized, controlled, and double-blinded clinical trial.

Patient Sample

After Institutional Review Board approval, 100 consecutive patients requiring single- or double level spinal fusion procedures were randomized into two groups—PA and control (C).

Methods

The PA group received P, K, and PR 4 hours before surgery, as PA. Both groups underwent identical anesthetic and postoperative pain management protocol.

Outcome Measures

Demographic and surgical data, 4 hourly postoperative pain levels—Numeric Pain Rating scale (NRS), Ambulatory NRS scores; level of consciousness—Ramsay sedation scale, total amount of opioids consumed (TOC) through patient-controlled analgesia; functional levels—Oswestry Disability Index (ODI), surgical satisfaction index-North American Spine Society (NASS) satisfaction scale, duration of hospital stay, and all complications were recorded and analyzed. A research grant of 6,032 USD was obtained from AO Spine toward this work. There is no conflict to disclose.

Results

Both the groups had identical demographic backgrounds and surgical profiles. The average NRS score within the first 48-hour period in the PA group (2.7±0.79) was significantly less than the C group (3.4±0.98) and the differences were more in the first 12 hours following surgery. Similarly, Ambulatory NRS scores were significantly low in the PA group during the first and second postoperative days. The PA group individuals were found to be more physically motivated, as 95.7% were able to ambulate 50 m on the first postoperative day compared with 30% in the C group. The PA group had significantly low TOC (3.02±2.29 mg) in comparison to the C group (4.94±3.08 mg). The duration of hospital stay was 4.17±1.02 and 4.84±1.62 days in the PA and C groups (p=.017), respectively. No major complications occurred in either groups and were found to be similar in percentage between both the groups, except for nausea and vomiting which were more in C group. Dry mouth was the most common side effect noted irrespective of the groups. All patients had significant improvement in ODI with better results in PA group at first month follow up. The PA group (97.90%) was extremely satisfied compared with C group (72%, p=.002) according to NASS scale.

Conclusions

Postoperative pain management in spine surgery is maximized if perioperative painful stimuli can be inhibited, which requires adequate blood levels of analgesic, anti-inflammatory, and neuropathic drugs intraoperatively. The employed strategy of preoperative administration of balanced analgesia with a combination of P, K, and PR, each having different mechanisms of action, resulted in lesser pain intensity, allowed better ambulation tolerance, improved functional outcomes and has also reduced the requirement of opioids and duration of hospital stay with no additional complications. Thus, this balanced analgesia administered preoperatively would address the complicated postsurgical pain.