Development and validation of severe hypoxemia associated risk prediction model in 1,000 mechanically ventilated patients*

The Effect of Conservative Oxygen Therapy in Reducing Mortality in Critical Care Patients: A Meta-Analysis and Trial Sequential Analysis

Background: Conservative oxygen therapy can prevent both hypoxemia and hyperoxemia, but the effect on the prognosis of patients admitted to the intensive care unit (ICU) remains controversial.

Methods: All controlled studies comparing conservative oxygen therapy and conventional oxygen therapy in adult patients admitted to the ICU were searched. The primary outcome was mortality, and the secondary outcomes were length of ICU stay (ICU LOS), length of hospital stay (hospital LOS), length of mechanical ventilation (MV) hours, new organ failure during ICU stay, and new infections during ICU stay.

Results: Nine trials with a total of 5,759 patients were pooled in our final studies. Compared with conventional oxygen therapy, conservative oxygen therapy did not reduce overall mortality (Z = 0.31, p = 0.75) or ICU LOS (Z = 0.17, p = 0.86), with firm evidence from trial sequential analysis, or hospital LOS (Z = 1.98, p = 0.05) or new infections during the ICU stay (Z = 1.45, p = 0.15). However, conservative oxygen therapy was associated with a shorter MV time (Z = 5.05, p < 0.00001), reduction of new organ failure during the ICU stay (Z = 2.15, p = 0.03) and lower risk of renal replacement therapy (RRT) (Z = 2.18, p = 0.03).

Conclusion: Conservative oxygen therapy did not reduce mortality but did decrease MV time, new organ failure and risk of RRT in critically ill patients.

Systematic Review Registration: identifier [CRD42020171055].

A catalogue of tools and variables from crisis and routine care to support decision-making about allocation of intensive care beds and ventilator treatment during pandemics: Scoping review

PURPOSE

This scoping review sought to identify objective factors to assist clinicians and policy-makers in making consistent, objective and ethically sound decisions about resource allocation when healthcare rationing is inevitable.

MATERIALS AND METHODS

Review of guidelines and tools used in ICUs, hospital wards and emergency departments on how to best allocate intensive care beds and ventilators either during routine care or developed during previous epidemics, and association with patient outcomes during and after hospitalisation.

RESULTS

Eighty publications from 20 countries reporting accuracy or validity of prognostic tools/algorithms, or significant correlation between prognostic variables and clinical outcomes met our eligibility criteria: twelve pandemic guidelines/triage protocols/consensus statements, twenty-two pandemic algorithms, and 46 prognostic tools/variables from non-crisis situations. Prognostic indicators presented here can be combined to create locally-relevant triage algorithms for clinicians and policy makers deciding about allocation of ICU beds and ventilators during a pandemic. No consensus was found on the ethical issues to incorporate in the decision to admit or triage out of intensive care.

CONCLUSIONS

This review provides a unique reference intended as a discussion starter for clinicians and policy makers to consider formalising an objective a locally-relevant triage consensus document that enhances confidence in decision-making during healthcare rationing of critical care and ventilator resources.

Does permissive hypoxaemia during extracorporeal membrane oxygenation cause long-term neurological impairment?: A study in patients with H1N1-induced severe respiratory failure

BACKGROUND

The Extracorporeal Life Support Organisation accepts permissive hypoxaemia in adult patients during extracorporeal membrane oxygenation (ECMO). The neurological long-term outcome of this approach has not yet been studied.

OBJECTIVES

We investigated the prevalence of brain lesions and cognitive dysfunction in survivors from the Influenza A/H1N1 2009 pandemic treated with permissive hypoxaemia during ECMO for severe acute respiratory distress syndrome (ARDS). Our hypothesis was that this method is reasonable if tissue hypoxia is avoided.

DESIGN

Long-term follow-up study after ECMO.

SETTING

Karolinska University Hospital, Sweden, from October 2012 to July 2013.

PATIENTS

Seven patients treated with ECMO for severe influenza A/H1N1-induced ARDS were studied 3.2 years after treatment. Blood lactate concentrations were used as a surrogate for tissue oxygenation.

INTERVENTIONS

Neurocognitive outcome was studied with standardised cognitive tests and MRI of the brain.

MAIN OUTCOME MEASURES

Cognitive functioning and hypoxic brain lesions after permissive hypoxaemia during ECMO. The observation period was the first 10 days of ECMO or the entire treatment period if shorter than 10 days.

RESULTS

Eleven of 13 patients were still alive 3 years after ECMO. We were able to contact seven of these patients (mean age 31 years), who all agreed to participate in this study. Mean ± SD peripherally measured arterial saturation during the observation period was 79 ± 10%. Full-scale Intelligence Quotient was within one standard deviation or above from the mean of a healthy population in five patients, and was 1.5 SD below the mean in one patient. In one other patient, it could not be determined because of a lack of formal education. Memory functioning was normal in all patients. MRI showed no changes related to cerebral hypoxia.

CONCLUSIONS

Permissive hypoxaemia during ECMO might not negatively affect long-term cognitive outcome if adequate organ perfusion is maintained.

TRIAL REGISTRATION

at Clinicaltrials.gov NCT01763060.

Pulmonary ultrasound scoring system for intubated critically ill patients and its association with clinical metrics and mortality: A prospective cohort study

PURPOSE

Pulmonary ultrasound (PU) examination at the point-of-care can rapidly identify the etiology of acute respiratory failure (ARF) and assess treatment response. The often-subjective classification of PU abnormalities makes it difficult to document change over time and communicate findings across providers. The study goal was to develop a simple, PU scoring system that would allow for standardized documentation, have high interprovider agreement, and correlate with clinical metrics.

METHODS

In this prospective study of 250 adults intubated for ARF, a PU examination was performed at intubation, 48-hours later, and at extubation. A total lung score (TLS) was calculated. Clinical metrics and final diagnosis were extracted from the medical record.

RESULTS

TLS correlated positively with mortality (P = .03), ventilator hours (P = .003), intensive care unit, and hospital length of stay (P = .003, P = .008), and decreasing PaO₂ /FiO₂ (P < .001). Agreement of PU findings was very good (kappa = 0.83). Baseline TLS and subscores differed significantly between ARF categories (nonpulmonary, obstructive, and parenchymal disease).

CONCLUSIONS

A quick, scored, PU examination was associated with clinical metrics, including mortality among a diverse population of patients intubated for ARF. In addition to diagnostic and prognostic information at the bedside, a standardized and quantifiable approach to PU provides objectivity in serial assessment and may enhance communication of findings between providers.

Retrospective report of contraindications to extracorporeal membrane oxygenation (ECMO) among adults with acute respiratory distress syndrome (ARDS)

OBJECTIVES

To determine the incidence of contraindications to extracorporeal membrane oxygenation (ECMO) among adults with acute respiratory distress syndrome (ARDS) and assess the impact of contraindications on the number of patients receiving ECMO (case volume).

BACKGROUND

The extent to which contraindications may affect case volumes has not been described.

METHODS

Retrospective, observational study at an academic tertiary medical center. The records of 730 consecutive patients with ARDS were queried for respiratory ECMO eligibility and ECMO contraindications.

RESULTS

Of the 730 patients with ARDS, 168 (23.0%) met ECMO inclusion criteria and 515 (70.5%) never met ECMO eligibility due to inadequately severe disease. Among 168 patients who met ECMO inclusion criteria, 1 or more relative contraindications were present in 144 (85.7%) patients. The three most common relative contraindications were immunocompromised state (58.3%), multiorgan dysfunction (29.2%) and contraindication to anticoagulation (16.7%).

CONCLUSIONS

Application of relative contraindications may greatly affect ECMO case volumes.