Respiratory Mechanics and Outcomes in Immunocompromised Patients With ARDS: A Secondary Analysis of the EFRAIM Study

[Non-invasive ventilation in acute respiratory failure of oncology-hematology patients: What are its current benefits and limitations?]

Acute respiratory failure (ARF) is a leading cause, along with sepsis, of admission to the intensive care unit (ICU) of patients with active cancer. Presenting variable clinical severity, ARF in onco-hematological patients has differing etiologies, primarily represented by possibly opportunistic acute infectious pneumonia (de novo hypoxemic ARF), and decompensation in chronic cardiac or respiratory diseases (e.g., acute pulmonary edema or exacerbated chronic obstructive pulmonary disease). In these patients, orotracheal intubation is associated with a doubled risk of in-hospital mortality. Consequently, over the last three decades, numerous researchers have attempted to demonstrate and pinpoint the precise role of non-invasive ventilation (NIV) in the specific context of ARF in onco-hematological patients. While the benefits of NIV in the management of acute pulmonary edema or alveolar hypoventilation (hypercapnic ARF) are well-demonstrated, its positioning in de novo hypoxemic ARF is debatable, and has recently been called into question. In the early 2000s, based on randomized controlled trials, NIV was recommended as first-line treatment, one reason being that it allowed significantly reduced use of orotracheal intubation. In the latest randomized studies, however, the benefits of NIV in terms of survival orotracheal intubation have not been observed; as a result, it is no longer recommended in the management of de novo hypoxemic ARF in onco-haematological patients.

How I manage acute respiratory failure in patients with hematological malignancies

ABSTRACT

Acute respiratory failure (ARF) is common in patients with hematological malignancies notably those with acute leukemia, myelodysplastic syndrome, or allogeneic stem cell transplantation. ARF is the leading reason for intensive care unit (ICU) admission, with a 35% case fatality rate. Failure to identify the ARF cause is associated with mortality. A prompt, well-designed diagnostic workup is crucial. The investigations are chosen according to pretest diagnostic probabilities, estimated by the DIRECT approach: D stands for delay, or time since diagnosis; I for pattern of immune deficiency; R and T for radiological evaluation; E refers to clinical experience, and C to the clinical picture. Thorough familiarity with rapid diagnostic tests helps to decrease the use of bronchoscopy with bronchoalveolar lavage, which can cause respiratory status deterioration in those patients with hypoxemia. A prompt etiological diagnosis shortens the time on unnecessary empirical treatments, decreasing iatrogenic harm and costs. High-quality collaboration between intensivists and hematologists and all crossdisciplinary health care workers is paramount. All oxygen delivery systems should be considered to minimize invasive mechanical ventilation. Treatment of the malignancy is started or continued in the ICU under the guidance of the hematologists. The goal is to use the ICU as a bridge to recovery, with the patient returning to the hematology ward in sufficiently good clinical condition to receive optimal anticancer treatment.

Sepsis and acute respiratory failure in patients with cancer: how can we improve care and outcomes even further?

PURPOSE OF REVIEW

Care and outcomes of critically ill patients with cancer have improved over the past decade. This selective review will discuss recent updates in sepsis and acute respiratory failure among patients with cancer, with particular focus on important opportunities to improve outcomes further through attention to phenotyping, predictive analytics, and improved outcome measures.

RECENT FINDINGS

The prevalence of cancer diagnoses in intensive care units (ICUs) is nontrivial and increasing. Sepsis and acute respiratory failure remain the most common critical illness syndromes affecting these patients, although other complications are also frequent. Recent research in oncologic sepsis has described outcome variation - including ICU, hospital, and 28-day mortality - across different types of cancer (e.g., solid vs. hematologic malignancies) and different sepsis definitions (e.g., Sepsis-3 vs. prior definitions). Research in acute respiratory failure in oncology patients has highlighted continued uncertainty in the value of diagnostic bronchoscopy for some patients and in the optimal respiratory support strategy. For both of these syndromes, specific challenges include multifactorial heterogeneity (e.g. in etiology and/or underlying cancer), delayed recognition of clinical deterioration, and complex outcomes measurement.

SUMMARY

Improving outcomes in oncologic critical care requires attention to the heterogeneity of cancer diagnoses, timely recognition and management of critical illness, and defining appropriate ICU outcomes.

[Invasive mechanical ventilation in patients with solid tumor or hematological malignancy]

Invasive mechanical ventilation in onco-hematology patients has become relatively routine, and is now part and parcel of their care pathway. Nevertheless, specific complications and subsequent therapeutic possibilities require discussion. To a greater extent than with regard to other patient populations, cooperation between specialist and ICU physician is mandatory, the objective being to more comprehensively assess a therapeutic project before or during the period of invasive mechanical ventilation. After an overview of recent results concerning ventilated patients in intensive care, this review aims to describe the specific complications and factors associated with mortality in this population.

Oxygenation strategy during acute respiratory failure in immunocompromised patients

Acute respiratory failure (ARF) in immunocompromised patients remains challenging to treat. A large number of case require admission to intensive care unit (ICU) where mortality remains high. Oxygenation without intubation is important in this setting. This review summarizes recent studies assessing oxygenation devices for immunocompromised patients. Previous studies showed that non-invasive ventilation (NIV) has been associated with lower intubation and mortality rates. Indeed, in recent years, the outcomes of immunocompromised patients admitted to the ICU have improved. In the most recent randomized controlled trials, including immunocompromised patients admitted to the ICU with ARF, neither NIV nor high-flow nasal oxygen (HFNO) could reduce the mortality rate. In this setting, other strategies need to be tested to decrease the mortality rate. Early admission strategy and avoiding late failure of oxygenation strategy have been assessed in retrospective studies. However, objective criteria are still lacking to clearly discriminate time to admission or time to intubation. Also, diagnosis strategy may have an impact on intubation or mortality rates. On the other hand, lack of diagnosis has been associated with a higher mortality rate. In conclusion, improving outcomes in immunocompromised patients with ARF may include strategies other than the oxygenation strategy alone. This review discusses other unresolved questions to decrease mortality after ICU admission in such patients.

Respiratory mechanics and mortality in coronavirus disease 2019 acute respiratory distress syndrome: A retrospective cohort study

Background:

The association between commonly monitored respiratory parameters, including compliance and oxygenation and clinical outcomes in acute respiratory distress syndrome (ARDS) from coronavirus disease 2019 (COVID-19) remains unclear, limiting prognostication and the delivery of targeted treatments. Our project aim was to identify if any such associations exist between clinical outcomes and respiratory parameters.

Methods:

We performed a retrospective observational cohort study of confirmed COVID-19 positive patients admitted to a single dedicated intensive care unit at a university hospital from March 27 to April 26, 2020. We collected information on baseline clinical and demographic characteristics and initial respiratory parameters. Our primary outcome was in-hospital mortality.

Results:

A total of 22 patients met criteria for ARDS and were included in our study. Nine of the 22 (40.9%) patients with ARDS died during hospitalization. The initial static respiratory system compliance of survivors was 39 (interquartile range [IQR] 34, 55) and nonsurvivors was 27 (IQR 24, 33, P < 0.01). A lower respiratory system compliance was associated with an increased adjusted odd of in-hospital mortality (odds ratio 1.2, 95% confidence interval 1.01, 1.45 P = 0.04).

Conclusion:

In our cohort of 22 patients mechanically ventilated with ARDS from COVID-19, having lower respiratory system compliance after intubation was associated with an increased risk of in-hospital mortality, consistent with ARDS from non-COVID etiologies.

Driving pressure monitoring during acute respiratory failure in 2020

PURPOSE OF REVIEW

Assess the most recent studies using driving pressure (DP) as a monitoring technique under mechanical ventilation and describe the technical challenges associated with its measurement.

RECENT FINDINGS

DP is consistently associated with survival in acute respiratory failure and acute respiratory distress syndrome (ARDS) and can detect patients at higher risk of ventilator-induced lung injury. Its measurement can be challenged by leaks and ventilator dyssynchrony, but is also feasible under pressure support ventilation. Interestingly, an aggregated summary of published results suggests that its level is on average slightly lower in patients with coronavirus disease-19 induced ARDS than in classical ARDS.

SUMMARY

The DP is easy to obtain and should be incorporated as a minimal monitoring technique under mechanical ventilation.