Red Flags For Necrotizing Fasciitis: A Case Control Study

Objective: to examine the diagnostic accuracy of traditional ‘red flags’ for necrotizing fasciitis (NF) on history and physical examination. Methods: retrospective study of all cases of NF admitted to a large tertiary care hospital between January 1 2004 and December 31 2013, each matched to two control patients with cellulitis. We determined the diagnostic test characteristics of clinical features for distinguishing NF from cellulitis, with emphasis on positive (LR+) and negative (LR-) likelihood ratios. Results: There were no individual findings with sufficient sensitivity to rule out NF (sensitivity ≤ 85% and LR- ≥ 0.5 for all findings). The clinical features that most significantly increased the odds of NF were recent surgery (LR+ 7.0) pain-out-of-proportion (LR+ 4.5), diarrhea (LR+ 6.0), hypotension (LR+ 8.0), altered mental status (LR+ 3.3), erythema progressing beyond margins (LR+3.1), fluctuance (LR+ 5.0), hemorrhagic bullae (LR+ 8.0) and skin necrosis (LR+ 30.0). Each individual finding conferred low sensitivity, but absence of all nine ruled out NF (LR- 0.04). The presence of >=3 findings ruled in NF (LR+ undefined). Conclusions: When considered together, the traditional ‘red flags’ for NF may be sufficient to rule in or rule out the diagnosis. If future prospective studies validate these findings, there will be a potential opportunity to expedite NF diagnosis and improve patient outcomes

SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study

Background: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods: The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18-49, 50-69, 70 or more years) and type of surgery. Best- and worst-case scenarios were used to describe uncertainty. Results: NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351; best case 196, worst case 816) or non-cancer surgery (733; best case 407, worst case 1664). Both exceeded the NNV in the general population (1840; best case 1196, worst case 3066). NNVs for surgical patients remained favourable at a range of SARS-CoV-2 incidence rates in sensitivity analysis modelling. Globally, prioritizing preoperative vaccination of patients needing elective surgery ahead of the general population could prevent an additional 58 687 (best case 115 007, worst case 20 177) COVID-19-related deaths in 1 year. Conclusion: As global roll out of SARS-CoV-2 vaccination proceeds, patients needing elective surgery should be prioritized ahead of the general population