A Meta-Analysis of the Utility of Preoperative Intravenous Paracetamol for Post-Caesarean Analgesia

Abstract

Background and objectives: Worldwide, the number of caesarean sections performed has increased exponentially. Some studies have reported better pain control and lower postoperative requirements for opioids when intravenous (IV) paracetamol was administered preoperatively. This meta-analysis thus aimed to investigate the utility of preoperative IV paracetamol for post-caesarean analgesia. Materials and Methods: By using the keywords (paracetamol OR acetaminophen) AND [cesarea* OR caesarea* OR cesaria* OR caesaria*], a systematic literature search was conducted using PubMed, Medline, Embase, Google Scholar and ClinicalTrials.gov databases for papers published in English between January 1, 1960 and March 1, 2019. Grey literature was searched as well. Results: Seven clinical trials were reviewed, while five randomized, placebo-controlled, double-blind studies were included in the final meta-analysis. Applying per-protocol analysis and a random-effects model, there was a significant reduction in postoperative opioid consumption and pain score in the group that received preoperative IV paracetamol, compared to placebo, as the standardized mean difference (SMD) were −0.460 (95% CI −0.828 to −0.092, p = 0.014) and −0.719 (95% CI: −1.31 to −0.13, p = 0.018), respectively. However, there was significant heterogeneity amongst the different studies included in the meta-analysis (I2 = 70.66%), perhaps owing to their diverse protocols. Some studies administered IV paracetamol 15 min before induction while others gave it before surgical incision. Conclusion: This is the first review on the topic. Overall, preoperative IV paracetamol has convincingly demonstrated useful opioid-sparing effects and it also appears safe for use at the time of delivery. It should be considered as a component of an effective multimodal analgesic regimen. Future studies could be conducted on other patient groups, e.g., those with multiple comorbidities or chronic pain disorders, and further delineate the optimal timing to administer the drug preoperatively.

Pre-emptive analgesic efficacy of injected ketorolac in comparison to other agents for third molar surgical removal: a systematic review

“…algesia, which can result in increased pain postoperatively and also pain that will not respond to analgesics. Any Evidence regarding the efficacy of pre-emptive analgesia administration is still weak in the field of medicine and dentistry, and the concept of pre-emptive analgesia administration is still a subject of debate, with few individual systematic reviews reporting positive benefits [3,4] and other few contradicting the same [5].…”

The efficacy and safety of paracetamol for pain relief: an overview of systematic reviews

“…We identified 3570 potentially relevant publications, of which 36 systematic reviews 15‐50 were ultimately included in our analysis (Box 1; , table 3). Of 112 publications deemed potentially eligible by abstract review, 76 were excluded after reviewing the full text (Box 1; , table 4); the conclusions of excluded reviews that covered the same topic as reviews included in our overview are summarised in , table 5.…”

“…Very low quality evidence was deemed inconclusive, even if the effect estimate was statistically significant. Evidence regarding the value of paracetamol was insufficient to guide treatment in seventeen pain conditions for which RCT evidence was available: chronic low back pain, 28 post‐caesarean delivery pain 45 (multiple‐dose regimens), prevention of post‐operative pain at rest, 23 endodontic surgery pain, 37 knee and hip arthroplasty 42 (single or multiple dose regimens), abdominal surgery 32 (multiple dose regimens), rheumatoid arthritis, 16 hip fracture, 41 tonsillectomy in adults, 47 laparoscopic cholecystectomy, 21 catheter‐related bladder discomfort, 22 myringotomy in children, 48 bariatric surgery, 43 cardiac surgery, 33 and diverse post‐operative pain conditions (thyroidectomy, lower extremity, lumbar disk, nephrolithotomy) 26 (Box 3). Evidence regarding its value in four conditions without RCT evidence was also very low quality: non‐cancer pain in children and adolescents, 40 neuropathic pain, 38 cancer pain in adults, 39 and hip fracture 41 …”

“…Adverse events data were assessed in 21 systematic reviews (, table 11) 15‐19,21,23,26‐31,33‐35,43‐46,48 . One systematic review found moderate level evidence that the risk of transiently elevated liver enzymes (two weeks to three months after administration) was greater for paracetamol than placebo in patients with spinal pain or osteoarthritis (RR, 3.8; 95% CI, 1.9–7.4); 44 the clinical implications of this finding, however, were unclear.…”

Opioid‐free multimodal analgesia pathway to decrease opioid utilization after cesarean delivery

“…The results showed that the pain scores and the cumulative opioid consumption in the IV acetaminophen group were lower compared to the placebo 20 . Recently, a meta‐analysis of five randomized, placebo‐controlled, double‐blind trials for women undergoing CD found a significant reduction in postoperative opioid consumption for patients that received a preoperative dose of IV acetaminophen compared to placebo 21 …”