Delivering evidence-based critical care for mechanically ventilated patients with COVID-19

Sepsis in patients hospitalized with coronavirus disease 2019: how often and how severe?

PURPOSE OF REVIEW

To discuss why severe COVID-19 should be considered sepsis and how co-infection and secondary infection can aggravate this condition and perpetuate organ dysfunction leading to high mortality rates.

RECENT FINDINGS

In severe COVID-19, there is both direct viral toxicity and dysregulated host response to infection. Although both coinfection and/or secondary infection are present, the latest is of greater concern mainly in resource-poor settings. Patients with severe COVID-19 present a phenotype of multiorgan dysfunction that leads to death in an unacceptable high percentage of the patients, with wide variability around the world. Similarly to endemic sepsis, the mortality of COVID-19 critically ill patients is higher in low-income and middle-income countries as compared with high-income countries. Disparities, including hospital strain, resources limitations, higher incidence of healthcare-associated infections (HAI), and staffing issues could in part explain this variability.

SUMMARY

The high mortality rates of critically ill patients with severe COVID-19 disease are not only related to the severity of patient disease but also to modifiable factors, such as the ICU strain, HAI incidence, and organizational aspects. Therefore, HAI prevention and the delivery of best evidence-based care for these patients to avoid additional damage is important. Quality improvement interventions might help in improving outcomes mainly in resource-limited settings.

Ventilation management and clinical outcomes in invasively ventilated patients with COVID-19 (PRoVENT-COVID): a national, multicentre, observational cohort study

BACKGROUND

Little is known about the practice of ventilation management in patients with COVID-19. We aimed to describe the practice of ventilation management and to establish outcomes in invasively ventilated patients with COVID-19 in a single country during the first month of the outbreak.

METHODS

PRoVENT-COVID is a national, multicentre, retrospective observational study done at 18 intensive care units (ICUs) in the Netherlands. Consecutive patients aged at least 18 years were eligible for participation if they had received invasive ventilation for COVID-19 at a participating ICU during the first month of the national outbreak in the Netherlands. The primary outcome was a combination of ventilator variables and parameters over the first 4 calendar days of ventilation: tidal volume, positive end-expiratory pressure (PEEP), respiratory system compliance, and driving pressure. Secondary outcomes included the use of adjunctive treatments for refractory hypoxaemia and ICU complications. Patient-centred outcomes were ventilator-free days at day 28, duration of ventilation, duration of ICU and hospital stay, and mortality. PRoVENT-COVID is registered at ClinicalTrials.gov (NCT04346342).

FINDINGS

Between March 1 and April 1, 2020, 553 patients were included in the study. Median tidal volume was 6·3 mL/kg predicted bodyweight (IQR 5·7-7·1), PEEP was 14·0 cm H₂O (IQR 11·0-15·0), and driving pressure was 14·0 cm H₂O (11·2-16·0). Median respiratory system compliance was 31·9 mL/cm H₂O (26·0-39·9). Of the adjunctive treatments for refractory hypoxaemia, prone positioning was most often used in the first 4 days of ventilation (283 [53%] of 530 patients). The median number of ventilator-free days at day 28 was 0 (IQR 0-15); 186 (35%) of 530 patients had died by day 28. Predictors of 28-day mortality were gender, age, tidal volume, respiratory system compliance, arterial pH, and heart rate on the first day of invasive ventilation.

INTERPRETATION

In patients with COVID-19 who were invasively ventilated during the first month of the outbreak in the Netherlands, lung-protective ventilation with low tidal volume and low driving pressure was broadly applied and prone positioning was often used. The applied PEEP varied widely, despite an invariably low respiratory system compliance. The findings of this national study provide a basis for new hypotheses and sample size calculations for future trials of invasive ventilation for COVID-19. These data could also help in the interpretation of findings from other studies of ventilation practice and outcomes in invasively ventilated patients with COVID-19.

FUNDING

Amsterdam University Medical Centers, location Academic Medical Center.

Care bundles for improving outcomes in patients with COVID-19 or related conditions in intensive care - a rapid scoping review

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the strain of coronavirus that causes coronavirus disease 2019 (COVID-19) can cause serious illness in some people resulting in admission to intensive care units (ICU) and frequently, ventilatory support for acute respiratory failure. Evaluating ICU care, and what is effective in improving outcomes for these patients is critical. Care bundles, a small set of evidence-based interventions, delivered together consistently, may improve patient outcomes. To identify the extent of the available evidence on the use of care bundles in patients with COVID-19 in the ICU, the World Health Organization (WHO) commissioned a scoping review to inform WHO guideline discussions. This review does not assess the effectiveness of the findings, assess risk of bias, or assess the certainty of the evidence (GRADE). As this review was commissioned to inform guideline discussions, it was done rapidly over a three-week period from 26 October to 18 November 2020.

OBJECTIVES

To identify and describe the available evidence on the use of care bundles in the ICU for patients with COVID-19 or related conditions (acute respiratory distress syndrome (ARDS) viral pneumonia or pneumonitis), or both. In carrying out the review the focus was on characterising the evidence base and not evaluating the effectiveness or safety of the care bundles or their component parts.

SEARCH METHODS

We searched MEDLINE, Embase, the Cochrane Library (CENTRAL and the Cochrane COVID-19 Study Register) and the WHO International Clinical Trials Registry Platform on 26 October 2020.

SELECTION CRITERIA

Studies of all designs that reported on patients who are critically ill with COVID-19, ARDS, viral pneumonia or pneumonitis, in the ICU setting, where a care bundle was implemented in providing care, were eligible for inclusion. One review author (VS) screened all records on title and abstract. A second review author (DR) checked 20% of excluded and included records; agreement was 99.4% and 100% respectively on exclude/include decisions. Two review authors (VS and DR) independently screened all records at full-text level. VS and DR resolved any disagreements through discussion and consensus, or referral to a third review author (AN) as required.

DATA COLLECTION AND ANALYSIS

One review author (VS) extracted the data and a second review author (DR) checked 20% of this for accuracy. As the review was not designed to synthesise effectiveness data, assess risk of bias, or characterise the certainty of the evidence (GRADE), we mapped the extracted data and presented them in tabular format based on the patient condition; that is patients with confirmed or suspected COVID-19, patients with ARDS, patients with any influenza or viral pneumonia, patients with severe respiratory failure, and patients with mixed conditions. We have also provided a narrative summary of the findings from the included studies.

MAIN RESULTS

We included 21 studies and identified three ongoing studies. The studies were of variable designs and included a systematic review of standardised approaches to caring for critically ill patients in ICU, including but not exclusive to care bundles (1 study), a randomised trial (1 study), prospective and retrospective cohort studies (4 studies), before and after studies (7 studies), observational quality improvement reports (4 studies), case series/case reports (3 studies) and audit (1 study). The studies were conducted in eight countries, most commonly China (5 studies) and the USA (4 studies), were published between 1999 and 2020, and involved over 2000 participants in total. Studies categorised participant conditions patients with confirmed or suspected COVID-19 (7 studies), patients with ARDS (7 studies), patients with another influenza or viral pneumonia (5 studies), patients with severe respiratory failure (1 study), and patients with mixed conditions (1 study). The care bundles described in the studies involved multiple diverse practices. Guidance on ventilator settings (10 studies), restrictive fluid management (8 studies), sedation (7 studies) and prone positioning (7 studies) were identified most frequently, while only one study mentioned chest X-ray. None of the included studies reported the prespecified outcomes ICU-acquired weakness (muscle wasting, weight loss) and users' experience adapting care bundles. Of the remaining prespecified outcomes, 14 studies reported death in ICU, nine reported days of ventilation (or ventilator-free days), nine reported length of stay in ICU in days, five reported death in hospital, three reported length of stay in hospital in days, and three reported adherence to the bundle.

AUTHORS' CONCLUSIONS

This scoping review has identified 21 studies on care bundle use in critically ill patients in ICU with COVID-19, ARDS, viral influenza or pneumonia and severe respiratory failure. The data for patients with COVID-19 specifically are limited, derived mainly from observational quality improvement or clinical experiential accounts. Research is required, urgently, to further assess care bundle use and optimal components of these bundles in this patient cohort. The care bundles described were also varied, with guidance on ventilator settings described in 10 care bundles, while chest X-ray was part mentioned in one care bundle in one study only. None of the studies identified in this scoping review measured users' experience of adapting care bundles. Optimising care bundle implementation requires that the components of the care bundle are collectively and consistently applied. Data on challenges, barriers and facilitators to implementation are needed. A formal synthesis of the outcome data presented in this review and a critical appraisal of the evidence is required by a subsequent effectiveness review. This subsequent review should further explore effect estimates across the included studies.

Ventilation management and clinical outcomes in invasively ventilated patients with COVID-19 (PRoVENT-COVID): a national, multicentre, observational cohort study

BACKGROUND

Little is known about the practice of ventilation management in patients with COVID-19. We aimed to describe the practice of ventilation management and to establish outcomes in invasively ventilated patients with COVID-19 in a single country during the first month of the outbreak.

METHODS

PRoVENT-COVID is a national, multicentre, retrospective observational study done at 18 intensive care units (ICUs) in the Netherlands. Consecutive patients aged at least 18 years were eligible for participation if they had received invasive ventilation for COVID-19 at a participating ICU during the first month of the national outbreak in the Netherlands. The primary outcome was a combination of ventilator variables and parameters over the first 4 calendar days of ventilation: tidal volume, positive end-expiratory pressure (PEEP), respiratory system compliance, and driving pressure. Secondary outcomes included the use of adjunctive treatments for refractory hypoxaemia and ICU complications. Patient-centred outcomes were ventilator-free days at day 28, duration of ventilation, duration of ICU and hospital stay, and mortality. PRoVENT-COVID is registered at ClinicalTrials.gov (NCT04346342).

FINDINGS

Between March 1 and April 1, 2020, 553 patients were included in the study. Median tidal volume was 6·3 mL/kg predicted bodyweight (IQR 5·7-7·1), PEEP was 14·0 cm H₂O (IQR 11·0-15·0), and driving pressure was 14·0 cm H₂O (11·2-16·0). Median respiratory system compliance was 31·9 mL/cm H₂O (26·0-39·9). Of the adjunctive treatments for refractory hypoxaemia, prone positioning was most often used in the first 4 days of ventilation (283 [53%] of 530 patients). The median number of ventilator-free days at day 28 was 0 (IQR 0-15); 186 (35%) of 530 patients had died by day 28. Predictors of 28-day mortality were gender, age, tidal volume, respiratory system compliance, arterial pH, and heart rate on the first day of invasive ventilation.

INTERPRETATION

In patients with COVID-19 who were invasively ventilated during the first month of the outbreak in the Netherlands, lung-protective ventilation with low tidal volume and low driving pressure was broadly applied and prone positioning was often used. The applied PEEP varied widely, despite an invariably low respiratory system compliance. The findings of this national study provide a basis for new hypotheses and sample size calculations for future trials of invasive ventilation for COVID-19. These data could also help in the interpretation of findings from other studies of ventilation practice and outcomes in invasively ventilated patients with COVID-19.

FUNDING

Amsterdam University Medical Centers, location Academic Medical Center.