Variation in outcome of invasive mechanical ventilation between different countries for patients with severe COVID-19: A systematic review and meta-analysis

Abstract

Background COVID 19 is the most recent cause of Adult respiratory distress syndrome ARDS. Invasive mechanical ventilation IMV can support gas exchange in patients failing non-invasive ventilation, but its reported outcome is highly variable between countries. We conducted a systematic review and meta-analysis on IMV for COVID-associated ARDS to study its outcome among different countries. Methods CENTRAL, MEDLINE/PubMed, Cochrane Library, and Scopus were systematically searched up to August 8, 2020. Studies reporting five or more patients with end point outcome for severe COVID 19 infection treated with IMV were included. The main outcome assessed was mortality. Baseline, procedural, outcome, and validity data were systematically appraised and pooled with random-effect methods. Subgroup analysis for different countries was performed. Meta-regression for the effect of study timing and patient age and were tested. Publication bias was examined. This trial was registered with PROSPERO under registration number CRD42020190365. Findings Our electronic search retrieved 4770 citations, 103 of which were selected for full-text review. Twenty-one studies with a combined population of 37359 patients with COVID-19 fulfilled the inclusion criteria. From this population, 5800 patients were treated by invasive mechanical ventilation. Out of those, 3301 patients reached an endpoint of ICU discharge or death after invasive mechanical ventilation while the rest were still in the ICU. Mortality from IMV was highly variable among the included studies ranging between 21% and 100%. Random-effect pooled estimates suggested an overall in-hospital mortality risk ratio of 0.70 (95% confidence interval 0.608 to 0.797; I2 = 98%). Subgroup analysis according to country of origin showed homogeneity in the 8 Chinese studies with high pooled mortality risk ratio of 0.97 (I2 = 24%, p = 0.23) (95% CI = 0.94–1.00), similar to Italy with a low pooled mortality risk ratio of 0.26 (95% CI 0.08–0.43) with homogeneity (p = 0.86) while the later larger studies coming from the USA showed pooled estimate mortality risk ratio of 0.60 (95% CI 0.43–0.76) with persistent heterogeneity (I2 = 98%, p<0.001). Meta-regression showed that outcome from IMV improved with time (p<0.001). Age had no statistically significant effect on mortality (p = 0.102). Publication bias was excluded by visualizing the funnel plot of standard error, Egger’s test with p = 0.714 and Begg&Mazumdar test with p = 0.334. Interpretation The study included the largest number of patients with outcome findings of IMV in this current pandemic. Our findings showed that the use of IMV for selected COVID 19 patients with severe ARDS carries a high mortality, but outcome has improved over the last few months and in more recent studies. The results should encourage physicians to use this facility when indicated for severely ill COVID-19 patients.

Programmed multi-level ventilation in COVID-19-related acute respiratory distress syndrome: a multi-center retrospective observational study

“…Mortality in our cohort (28%) coincided with the wide range of mortality reported in a systematic review and meta-analysis of 37,359 patients. 22 Although mortality in our cohort was relatively lower than that in other studies, 23 – 27 this finding cannot be generalized owing to the small number of patients and because of the collapsed state of the health care system when the COVID epidemic was at its peak in Slovakia. As a result, many patients were only stabilized using PMLV until such time as they could be transferred (while still on the ventilator) to other peripheral hospitals where weaning was commenced.…”

“…In comparison, several other studies from the same period or later have reported longer lengths of ICU stay, ranging from 10 to 15 days. [19][20][21][22] Whether these differences arise owing to the PMLV mode used in our study is an important area of further research. Any mode of ventilation that is closer to the physiological needs of the patient has the potential to reduce the length of stay in the ICU and would thus positively affect resource distribution, especially during periods of immense pressure on ICUs.…”

Neurologic manifestations of COVID-19 in critically ill patients: results of the prospective multicenter registry PANDEMIC

“…Overall ICU mortality in the preexisting literature on COVID-19 varies greatly depending on the geographic location, the period of analysis and the clinical characteristics of the analyzed cohort and ranges between 21 and 100% [ 41 – 43 ]. A German study performed in 2020 in ventilated patients reported a mortality of 38.8% [ 44 ].…”

Efficacy and safety of HD-tDCS and respiratory rehabilitation for critically ill patients with COVID-19 The HD-RECOVERY randomized clinical trial

“…Patients critically ill with coronavirus disease 2019 (COVID-19) often require mechanical ventilation and prolonged hospitalization duration to restore adequate gas exchange and to alleviate acute respiratory distress syndrome (ADRS) [ 1 ]. There is variability between individual studies with respect to frequency of ARDS caused by COVID-19 [ [2] , [3] , [4] ]; individual studies for which data is available indicate that among hospitalized COVID-19 patients, approximately 1/3 (33%) develop ARDS, 1/4 (26%) require transfer to an intensive care unit (ICU), and 1/6 (16%) receive invasive mechanical ventilation [ 5 ]. Injury to the brain - whether secondary to systemic (respiratory system) dysfunction, neuro-vascular damage, or direct neural-invasion (e.g., via the olfactory nerve) [ 6 ] contributes to COVID‐19 pathophysiology, symptoms, and progression [ 7 ].…”