Emergency front-of-neck airway: robust theatre multidisciplinary team training optimises performance and saves time.

Abstract

EditordRiddell and colleagues1 reported on a systematic review and meta-analysis of low-dose ketamine in orthopaedic surgery, concluding that low-dose ketamine was an effective adjuvant that decreased pain and opioid requirements in painful orthopaedic procedures. I do not believe their data support such a conclusion. \nThere were three nominated primary outcomes in their study:(i) total postoperative opioid consumption, (ii) time to the first dose of opioid after surgery (minutes), and (iii) pain scores at rest using the 10 cm visual analogue scale (VAS) at 12, 24, and 48 h. They included 20 studies in their meta-analysis and found that ketamine decreased total opioid use and pain VAS scores, and delayed the time to first opioid dose. These findings seem impressive and each were statistically significant. However, standardised mean difference and P-values tell us very little about clinical significance, the degree of statistical uncertainty, or both. \nIn their meta-analysis, the standardised mean differences and 95% confidence intervals of the morphine (?) dose reduc-tion were only 0.82 (0.40e1.24) mg at 24 h and 0.65 (0.27e1.03) at 48 h after surgery. These statistics reflect effect sizes but not actual clinical data about analgesic effectiveness or opioid-related side effects. The actual weighted mean reduction in pain VAS scores at 24 and 48 hours were not reported. Were they more than 1.0, previously defined by many investigators to be the minimal clinically important difference?2 Some au-thors have suggested that a 33% decrease,3 or a change in VAS score of 1.5 to 2.0,4�6 would indicate a clinically important change in pain intensity. As it stands, and considering the marked heterogeneity of the patient populations and keta-mine regimens, none of the findings presented by Riddell and colleagues suggests any clinically important analgesic benefits of low dose ketamine in orthopaedic surgery. \nThe Standardised Endpoints in Perioperative Medicine \n(StEP) initiative undertook an extensive Delphi process to identify important, valid and reliable measures of patient comfort after surgery.7 Postoperative pain intensity at rest andon movement at 24 h, using a numerical rating scale (0e10), and (ideally) at least one other time point, were recommended. Opioid dose reduction, of itself (i.e. without a reduction in opioid-related side-effects), was not considered important, nor was time to the first dose of opioid after surgery.