No abstract

The aim of this systematic review and meta-analysis was to examine the efficacy, time taken and the safety of neuraxial blockade performed for obstetric patients with the assistance of preprocedural ultrasound, in comparison with the landmark palpation method. The bibliographic databases Central, CINAHL, EMBASE, Global Health, MEDLINE, Scopus and Web of Science were searched from inception to 13 February 2020 for randomised controlled trials that included pregnant women having neuraxial procedures with preprocedural ultrasound as the intervention and conventional landmark palpation as the comparator. For continuous and dichotomous outcomes, respectively, we calculated the mean difference using the inverse-variance method and the risk ratio with the Mantel-Haenszel method. In all, 22 trials with 2462 patients were included. Confirmed by trial sequential analysis, preprocedural ultrasound increased the first-pass success rate by a risk ratio (95%CI) of 1.46 (1.16-1.82), p = 0.001 in 13 trials with 1253 patients. No evidence of a difference was found in the total time taken between preprocedural ultrasound and landmark palpation, with a mean difference (95%CI) of 50.1 (À13.7 to 113.94) s, p = 0.12 in eight trials with 709 patients. The quality of evidence was graded as low and very low, respectively, for these co-primary outcomes. Sub-group analysis underlined the increased benefit of preprocedural ultrasound for those in whom the neuraxial procedure was predicted to be difficult. Complications, including postpartum back pain and headache, were decreased with preprocedural ultrasound. The adoption of preprocedural ultrasound for neuraxial procedures in obstetrics is recommended and, in the opinion of the authors, should be considered as a standard of care, in view of its potential to increase efficacy and reduce complications without significant prolongation of the total time required.

BACKGROUND Central neuraxial modalities can occasionally be challenging to perform, particularly if the underlying anatomy is altered or obscured. OBJECTIVES To compare the efficacy, efficiency and the safety of preprocedural ultrasound to landmark palpation in the nonobstetric adult population. DESIGN Systematic review of randomised controlled trials with meta-analysis and trial sequential analysis. DATA SOURCES Systematic search of Central, CINAHL, Embase, Global Health, MEDLINE, Scopus and Web of Science to 13th February 2020. ELIGIBILITY CRITERIA Randomised controlled trials of nonobstetric adult patients having diagnostic and/or therapeutic neuraxial procedures using standard preprocedural ultrasound interpreted by the operator as the intervention and conventional landmark palpation as the comparator. KEY DEFINITIONS A skin puncture was defined as the insertion or reinsertion of the needle through the skin; needle redirection was the backward followed by the forward movement of the needle without its removal from the skin; first skin puncture referred to a single skin puncture with or without needle redirections; and first pass was a single skin puncture with no needle redirection. RESULTS In all, 18 randomised controlled trials with 1800 patients were included. The first pass success rate was not different between landmark and ultrasound methods [risk ratio 1.46; 95% confidence interval (CI), 0.99 to 2.16; P = 0.06, I 2 = 76%; moderate quality of evidence] and the trial sequential analysis demonstrated the futility of further randomisation of patients in modifying this finding. Preprocedural ultrasound increased the total time taken (mean difference 110.8 s; 95% CI, 31.01 to 190.65; P = 0.006; I 2 = 96%; moderate quality of evidence). Subgroup analyses revealed no influence of the predicted difficulty of the neuraxial procedure on outcomes. Compared with the landmark method, ultrasound increased the first skin puncture success rate (risk ratio 1.36; 95% CI, 1.18 to 1.57; P < 0.001; I 2 = 70%), and decreased the need for three or more skin punctures (risk ratio 0.46; 95% CI, 0.33 to 0.64; P < 0.001; I 2 = 29%) and the number of needle redirections (mean difference -1.24; 95% CI, -2.32 to -0.17; P = 0.020; I 2 = 83). The incidence of bloody tap was reduced with the use of ultrasound (risk ratio 0.61; 95% CI, 0.40 to 0.93; P = 0.020; I 2 = 42%). CONCLUSIONS The use of preprocedural ultrasound for neuraxial procedures in the nonobstetric adult population did not enhance the first pass success rate and increased the total time taken to a clinically insignificant extent. Improvement in secondary outcomes, including other markers of efficacy, should be interpreted with caution.

Extrinsic compression of the heart consequent to intrapleural fluid is a rare cause of cardiac tamponade. Cases of massive hemothorax resulting in external cardiac tamponade due to injury of the internal thoracic artery (ITA) following blunt or penetrating trauma have been described in the literature. Here, we present a case of iatrogenic injury to the right ITA complicating mastectomy and deep inferior epigastric perforator flap reconstruction. It manifested as hemodynamic instability that persisted despite aggressive fluid resuscitation. Investigation with an intraoperative transesophageal echocardiogram demonstrated cardiac tamponade secondary to a massive hemothorax which resolved following surgical placement of an intercostal drain.