Pickens Chiagozie O, Gao Catherine A, Cuttica Michael J, Smith Sean B, Pesce Lorenzo L, Grant Rogan A, Kang Mengjia, Morales-Nebreda Luisa, Bavishi Avni A, Arnold Jason M, Pawlowski Anna, Qi Chao, Budinger G R Scott, Singer Benjamin D, Wunderink Richard G
Division of Pulmonary and Critical Care, Department of Medicine.
Department of Pharmacology.
Am J Respir Crit Care Med. 2021 Oct 15;204(8):921-932. doi: 10.1164/rccm.202106-1354OC.
Current guidelines recommend patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia receive empirical antibiotics for suspected bacterial superinfection on the basis of weak evidence. Rates of ventilator-associated pneumonia (VAP) in clinical trials of patients with SARS-CoV-2 pneumonia are unexpectedly low. We conducted an observational single-center study to determine the prevalence and etiology of bacterial superinfection at the time of initial intubation and the incidence and etiology of subsequent bacterial VAP in patients with severe SARS-CoV-2 pneumonia. Bronchoscopic BAL fluid samples from all patients with SARS-CoV-2 pneumonia requiring mechanical ventilation were analyzed using quantitative cultures and a multiplex PCR panel. Actual antibiotic use was compared with guideline-recommended therapy. We analyzed 386 BAL samples from 179 patients with SARS-CoV-2 pneumonia requiring mechanical ventilation. Bacterial superinfection within 48 hours of intubation was detected in 21% of patients. Seventy-two patients (44.4%) developed at least one VAP episode (VAP incidence rate = 45.2/1,000 ventilator days); 15 (20.8%) initial VAPs were caused by difficult-to-treat pathogens. The clinical criteria did not distinguish between patients with or without bacterial superinfection. BAL-based management was associated with significantly reduced antibiotic use compared with guideline recommendations. In patients with SARS-CoV-2 pneumonia requiring mechanical ventilation, bacterial superinfection at the time of intubation occurs in <25% of patients. Guideline-based empirical antibiotic management at the time of intubation results in antibiotic overuse. Bacterial VAP developed in 44% of patients and could not be accurately identified in the absence of microbiologic analysis of BAL fluid.
当前指南建议，患有严重急性呼吸综合征冠状病毒2（SARS-CoV-2）肺炎的患者，基于薄弱证据，针对疑似细菌重叠感染接受经验性抗生素治疗。在SARS-CoV-2肺炎患者的临床试验中，呼吸机相关性肺炎（VAP）的发生率出人意料地低。我们进行了一项单中心观察性研究，以确定重症SARS-CoV-2肺炎患者初次插管时细菌重叠感染的患病率和病因，以及随后发生细菌性VAP的发生率和病因。对所有需要机械通气的SARS-CoV-2肺炎患者的支气管镜下支气管肺泡灌洗（BAL）液样本进行定量培养和多重聚合酶链反应（PCR）检测分析。将实际使用的抗生素与指南推荐的治疗方法进行比较。我们分析了179例需要机械通气的SARS-CoV-2肺炎患者的386份BAL样本。21%的患者在插管后48小时内检测到细菌重叠感染。72例患者（44.4%）发生至少1次VAP发作（VAP发生率=45.2/1000呼吸机日）；15例（20.8%）初次VAP由难治疗病原体引起。临床标准无法区分有无细菌重叠感染的患者。与指南建议相比，基于BAL的管理与抗生素使用显著减少相关。在需要机械通气的SARS-CoV-2肺炎患者中，插管时细菌重叠感染发生在不到25%的患者中。插管时基于指南的经验性抗生素管理导致抗生素过度使用。44%的患者发生细菌性VAP，在未对BAL液进行微生物分析的情况下无法准确识别。
