Study shows COVID-19 mortality linked to lack of respiratory support

Review finds lack of aggressive respiratory support in majority of patients dying from COVID-19-induced pneumonia An analysis of patients who died of pneumonia related to COVID-19 identified delayed intubation as a possible factor. The report, which was published April 1, 2020 [Xie J, et al. JAMA Netw Open. Apr 1;3(4):e205619], analysed characteristics of 168 patients who died while being treated as inpatients in Wuhan, China. Records were obtained from 21 hospitals for patients who died between January 21 and January 30, 2020. Although all patients had received oxygen therapy, only 34 patients (20%) were intubated and received invasive mechanical ventilation, and only two patients (1.2%) received extracorporeal membrane oxygenation. More than one-quarter of patients (27.4%) had received oxygen by only nasal or face mask. The authors postulated three reasons to explain why such a low proportion of patients received aggressive respiratory support. First, they suggested that severe hypoxemia may not have been recognised in some patients who may have lacked usual symptoms, such as shortness of breath or dyspnea. However, insufficient equipment for providing mechanical ventilation as well as a lack of medical personnel with critical care training may have also been contributing factors. The authors explained that medical team members who are not intensivists may be uncertain about the proper timing for intubation. Demographic analyses showed that three-quarters of the patients in the series were men. The median age of all patients was 70 years, and 161 patients (96%) were older than 50 years. Age, however, was not associated with intubation. Three-quarters of the 168 patients had one or more medical comorbidities, of which hypertension (50%), diabetes (25%), ischaemic heart disease (18.5%) and chronic lung disease (9%) were most common. The authors observed the finding that hypertension was the leading comorbidity among the patients in their series is consistent with a previously published case series of patients with COVID-19 that reported a higher prevalence of hypertension among those who were admitted to an intensive care unit compared to those who were not treated in the intensive care unit. Commenting further about the potential significance of the frequency of hypertension, the authors cited a report suggesting that the causative pathogen for COVID-19 infects the lungs through the angiotensin-converting enzyme II receptor. They called for further study to understand the mechanism of the pulmonary infection and to investigate a potential therapeutic role for medications that act as angiotensin-converting enzyme inhibitors or angiotensin receptor blockers. As a caveat pertaining to generalising the findings, the authors noted that the patients in their series may not be representative of those who died from COVID-19 later during the pandemic, after their study period.

Tags: covid-19 research