Pain treatment after craniotomy: where is the (procedure-specific) evidence? A qualitative systematic review.

Context and objective Pain following craniotomy has been demonstrated to be frequent and moderate-to-severe in nature. In recent years, the focus on the challenges in treatment of postoperative pain following craniotomy has increased. Fear of using opioids because of their wide array of side-effects has led to the search for alternative analgesic options. The objective of this systematic review was to evaluate current evidence about analgesic therapy following craniotomy. Data sources PubMed database, Embase, Cochrane library, Google scholar and the Cumulative Index to Nursing and Allied Health Literature. Eligibility criteria Randomised double-blinded placebo-controlled trials (RCTs) with pain or supplemental postoperative analgesic consumption as an endpoint were included in the analysis. Results A total of 34 RCTs were identified, and nine RCTs were included in the final analysis, with a total of 519 patients (251 control vs. 268 active treatment). Four treatment modalities scalp infiltration (five RCTs), nerve scalp block (two RCTs), parecoxib (one RCT) and patient-controlled analgesia with morphine (one RCT) - were evaluated. Scalp infiltration with local anaesthetic may provide adequate analgesia in the first few postoperative hours, and nerve scalp block may provide longer lasting analgesia for about 6 h. Morphine was found to reduce total analgesic rescue doses with no significant effect on nausea and no other side-effects. No significant evidence was found to support the use of parecoxib in the treatment of postcraniotomy pain. Conclusion No firm recommendations on analgesic therapy following craniotomy can be given because the number of well performed RCTs is limited and the study populations are very small. However, evidence on scalp infiltration suggests an analgesic effect in the first few postoperative hours. There is an urgent need for well performed RCTs on pain therapy following craniotomy. Eur J Anaesthesiol 2011;28:821-829