PARACETAMOL AND NSAIDS POST SURGERY

Paracetamol and selective and non-selective non-steroidal anti-inflammatory drugs (NSAIDs) for the reduction of morphine-related side-effects after major surgery: a systematic review  

Background

Paracetamol or non-steroidal anti-inflammatory drugs (NSAIDs), which include cyclo-oxygenase 2 inhibitors (COXIBs), are non-opioids that can be used in combination with morphine for severe post operative pain relief after major surgery. The rationale behind the use of paracetamol or NSAIDs in combination with morphine is that the amount of morphine required for pain relief should be reduced and, as a result, there should be a reduction in dose-related adverse effects of morphine such as post operative nausea and vomiting (PONV). This needs to be balanced against the risk of side-effects from the non-opioids.

The problem faced by decision makers in healthcare is which class of non-opioid analgesics, such as paracetamol and NSAIDs (selective and non-selective), is the most effective at reducing morphine consumption and opioid-associated adverse effects when used as part of post-operative analgesia after major surgery. Previous systematic reviews have not compared the three non-opioids to each other.

The primary objective of this project was to assess the effectiveness of paracetamol and NSAIDS (including COXIBs) in reducing morphine consumption and opioid-associated adverse effects after major surgery. This included assessment of the relative effectiveness of paracetamol NSAIDs and COXIBs. 

Findings

There was a decrease in 24 hour morphine consumption when paracetamol, NSAID or COX-2 inhibitors were added to PCA morphine following surgery. However, the benefits in terms of reduction of morphine related adverse effects did not strongly favour one of the three non-opioid analgesics. Given the overlap in the effects of the three analgesics, there did not appear to be a compelling case for a further trial. However, any future trials testing new analgesics in conjunction with morphine, following surgery, should focus on morphine related adverse effects, ensuring that the power calculation is based on key morphine related adverse effects rather than morphine consumption.

Conducted by: C McDaid1, E Maund1, S Rice1, K Wright1, B Jenkins1, N Woolacott1

1. Centre for Reviews and Dissemination

Further details

Project page on NIHR HTA Programme website

Publications

Maund E, McDaid C, Rice S, Wright K, Jenkins B, Woolacott N. Paracetamol and selective and non-selective non-steroidal anti-inflammatory drugs (NSAIDs) for the reduction of morphine-related side-effects after major surgery: a systematic review. Br J Anaesth 2011; 106(3): 292-7

McDaid C, Maund E, Rice S , Wright K, Jenkins B, Woolacott N. Paracetamol and selective and non-selective non-steroidal anti-inflammatory drugs (NSAIDs) for the reduction of morphine-related side-effects after major surgery: a systematic review. Health Technol Assess. 2010; 14(17):1-153

Funding

Commissioned by the NIHR HTA Programme as part of the Technology Assessment Report (TAR) process