Hospitalised COVID-19 outcomes are predicted by hypoxaemia and pneumonia phenotype irrespective of the timing of their emergence

Despite the known clinical importance of hypoxemia and pneumonia, there is a paucity of evidence for these variables with respect to risk of mortality and short-term outcomes among those hospitalised with COVID-19.

OBJECTIVE

Describe the prevalence and clinical course of patients hospitalised with COVID-19 based on oxygenation and pneumonia status at presentation and determine the incidence of emergent hypoxaemia or radiographic pneumonia during admission.

METHODS

A retrospective study was conducted using a Canadian regional registry. Patients were stratified according to hypoxaemia/pneumonia phenotype and prevalence. Clinical parameters were compared between phenotypes using χ² and one-way Analysis of variance (ANOVA). Cox analysis estimated adjusted Hazard Ratios (HR) for associations between disease outcomes and phenotypes.

RESULTS

At emergency department (ED) admission, the prevalence of pneumonia and hypoxaemia was 43% and 50%, respectively, and when stratified to phenotypes: 28.2% hypoxaemia⁺/pneumonia⁺, 22.2% hypoxaemia⁺/pneumonia^-, 14.5% hypoxaemia^-/pneumonia⁺ and 35.1% hypoxaemia^-/pneumonia^-. Mortality was 31.1% in the hypoxaemia⁺/pneumonia^- group and 26.3% in the hypoxaemia⁺/pneumonia⁺ group. Hypoxaemia with pneumonia and without pneumonia predicted higher probability of death. Hypoxaemia either <24 hours or ≥24 hours after hospitalisation predicted higher mortality and need for home oxygen compared with those without hypoxaemia. Patients with early hypoxaemia had higher probability of Intensive care unit (ICU) admission compared with those with late hypoxaemia.

CONCLUSION

Mortality in COVID-19 infection is predicted by hypoxaemia with or without pneumonia and was greatest in patients who initially presented with hypoxaemia. The emergence of hypoxaemia was predicted by radiographic pneumonia. Patients with early and emergent hypoxaemia had similar mortality but were less likely to be admitted to ICU. There may be delayed identification of hypoxaemia, which prevents timely escalation of care.

Impact of a multifaceted and multidisciplinary intervention on pain, agitation and delirium management in an intensive care unit: an experience of a Canadian community hospital in conducting a quality improvement project

BACKGROUND

Clinical guidelines suggest that routine assessment, treatment, and prevention of pain, agitation, and delirium (PAD) is essential to improving patient outcomes as delirium is associated with increased mortality and morbidity. Despite the well-established improvements on patient outcomes, adherence to PAD guidelines is poor in community intensive care units (ICU). This quality improvement (QI) project aims to evaluate the impact of a multifaceted and multidisciplinary intervention on PAD management in a Canadian community ICU and to describe the experience of a Canadian community hospital in conducting a QI project.

METHODS

A ten-member PAD advisory committee was formed to develop and implement the intervention. The intervention consisted of a multidisciplinary rounds script, poster, interviews, visual reminders, educational modules, pamphlet and video. The 4-week intervention targeted nurses, family members, physicians, and the multidisciplinary team. An uncontrolled, before-and-after study methodology was used. Adherence to PAD assessment guidelines by nurses was measured over a 6-week pre-intervention and over a 6-week post-intervention periods.

RESULTS

Data on 430 and 406 patient-days (PD) were available for analysis during the pre- and post- intervention periods, respectively. The intervention did not improve the proportion of PD with guideline compliance to the assessment of pain (23.4% vs. 22.4%, p=0.80), agitation (42.9% vs. 38.9%, p=0.28), nor delirium (35.2% vs. 29.6%, p=0.10) by nurses.

DISCUSSION

The implementation of a multifaceted and multidisciplinary intervention on PAD assessment did not result in significant improvements in guideline adherence in a community ICU. Barriers to knowledge translation are apparent at multiple levels including the personal level (low completion rates on educational modules), interventional level (under-collection of data), and organisational level (coinciding with hospital accreditation education). Our next steps include reintroduction of education modules using organisation approved platforms, updating existing ICU policy, updating admission order sets, and conducting audit and feedback.

Canadian Critical Care Society clinical practice guideline: The use of vasopressin and vasopressin analogues in critically ill adults with distributive shock

PURPOSE

Hemodynamic management of adults with distributive shock often includes the use of catecholamine-based vasoconstricting medications. It is unclear whether adding vasopressin or vasopressin analogues to catecholamine therapy is beneficial in the management of patients with distributive shock. The purpose of this guideline was to develop an evidence-based recommendation regarding the addition of vasopressin to catecholamine vasopressors in the management of adults with distributive shock.

METHODS

We summarized the evidence informing this recommendation by updating a recently published meta-analysis. Then, a multidisciplinary panel from the Canadian Critical Care Society developed the recommendation using Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology.

RESULTS

The updated systematic review identified 25 randomized controlled trials including a total of 3,737 patients with distributive shock. Compared with catecholamine therapy alone, the addition of vasopressin or its analogues was associated with a reduced risk of mortality (relative risk [RR], 0.91; 95% confidence interval [CI], 0.85 to 0.99; low certainty), reduced risk of atrial fibrillation (RR, 0.77; 95% CI, 0.67 to 0.88; high certainty), and increased risk of digital ischemia (RR, 2.56; 95% CI, 1.24 to 5.25; moderate certainty).

CONCLUSIONS

After considering certainty in the evidence, values and preferences, cost, and other factors, the expert guideline panel suggests using vasopressin or vasopressin analogues in addition to catecholamines over catecholamine vasopressors alone for the management of distributive shock (conditional recommendation, low certainty evidence).

Impact of a nurse engagement intervention on pain, agitation and delirium assessment in a community intensive care unit

Background

In 2013, the Society of Critical Care Medicine published a revised version of the ICU Pain, Agitation, and Delirium (PAD) guidelines. Immobility and sleep were subsequently added in 2018. Despite the well-established advantages of implementing these guidelines, adoption and adherence remain suboptimal. This is especially true in community settings, where PAD assessment is performed less often, and the implementation of PAD guidelines has not yet been studied. The purpose of this prospective interventional study is to evaluate the effect of a multifaceted nurse engagement intervention on PAD assessment in a community intensive care unit (ICU).

Methods

All patients admitted to our community ICU for over 24 hours were included. A 20-week baseline audit was performed, followed by the intervention, and a 20-week postintervention audit. The intervention consisted of a survey, focus groups and education sessions. Primary outcomes included rates of daily PAD assessment using validated tools.

Results

There were improvements in the number of patients with at least one assessment per day of pain (67.5% vs 59.3%, p=0.04), agitation (93.1% vs 78.7%, p<0.001) and delirium (54.2% vs 39.4%, p<0.001), and the number of patients with target Richmond Agitation-Sedation Scale ordered (63.1% vs 46.8%, p=0.002). There was a decrease in the rate of physical restraint use (10.0% vs 30.9%, p<0.001) and no change in self-extubation rate (0.9% vs 2.5%, p=0.2).

Conclusion

The implementation of a multifaceted nurse engagement intervention has the potential to improve rates of PAD assessment in community ICUs. Screening rates in our ICU remain suboptimal despite these improvements. We plan to implement multidisciplinary interventions targeting physicians, nurses and families to close the observed care gap.

Acute refractory hypoxemia after chest trauma reversed by high-frequency oscillatory ventilation: a case report

Introduction

Polytrauma often results in significant hypoxemia secondary to direct lung contusion or indirectly through atelectasis, systemic inflammatory response, large volume fluid resuscitation and blood product transfusion. In addition to causing hypoxemia, atelectasis and acute lung injury can lead to right ventricular failure through an acute increase in pulmonary vascular resistance. Mechanical ventilation is often applied, accompanied with recruitment maneuvers and positive end-expiratory pressure in order to recruit alveoli and reverse atelectasis, while preventing excessive alveolar damage. This strategy should lead to the reversal of the hypoxemic condition and the detrimental heart–lung interaction that may occur. However, as described in this case report, hemodynamic instability and intractable alveolar atelectasis sometimes do not respond to conventional ventilation strategies.

Case presentation

We describe the case of a 21-year-old Caucasian man with severe chest trauma requiring surgical interventions, who developed refractory hypoxemia and overt right ventricular failure. After multiple failed attempts of recruitment using conventional ventilation, the patient was ventilated with high-frequency oscillatory ventilation. This mode of ventilation allowed the reversal of the hemodynamic effects of severe hypoxemia and of the acute cor pulmonale. We use this case report to describe the physiological advantages of high-frequency oscillatory ventilation in patients with chest trauma, and formulate the arguments to explain the positive effect observed in our patient.

Conclusions

High-frequency oscillatory ventilation can be used in the context of a blunt chest trauma accompanied by severe hypoxemia due to atelectasis. The positive effect is due to its capacity to recruit the collapsed alveoli and, as a result, the relief of increased pulmonary vascular resistance and subsequently the reversal of acute cor pulmonale. This approach may represent an alternative in case of failure of the conventional ventilation strategy.

Regulation of apoptosis and priming of neutrophil oxidative burst by diisopropyl fluorophosphate

BACKGROUND

Diisopropyl fluorophosphate (DFP) is a serine protease inhibitor that is widely used as an inhibitor of endogenous proteases in in vitro neutrophil studies. Its effects on neutrophil function are unclear. We sought to determine the biological effects of DFP on human neutrophil apoptosis and oxidative burst.

METHODS

We isolated neutrophils from healthy volunteers, incubated them with DFP (2.5 mM), and evaluated neutrophil elastase (NE) activity, neutrophil degranulation, apoptosis as reflected in hypodiploid DNA formation and exteriorization of phosphatidylserine (PS), processing and activity of caspases-3 and -8, oxidative burst activity and hydrogen peroxide release.

RESULTS

Consistent with its activity as a serine protease inhibitor, DFP significantly inhibited NE activity but not the degranulation of azurophilic granules. DFP inhibited constitutive neutrophil apoptosis as reflected in DNA fragmentation, and the processing and activity of caspases-3 and -8. DFP also inhibited priming of neutrophils for oxidative burst activity and hydrogen peroxide release. However, DFP enhanced the exteriorization of PS in a dose-dependent manner.

CONCLUSION

We conclude that DFP exerts significant effects on neutrophil inflammatory function that may confound the interpretation of studies that use it for its antiprotease activity. We further conclude that endogenous proteases play a role in the biology of constitutive neutrophil apoptosis.