MedicalResearch.com Interview with:
John G. Laffey MD
Chief, Department of Anesthesia; Co-Director, Critical illness and Injury Research Centre; Scientist, Keenan Research Centre for Biomedical Science ‑ St. Michael's Hospital
Professor, Anesthesia, Critical Care, and Physiology ‑ University of Toronto
Medical Research: What is the background for this study?
Acute respiratory distress syndrome is the commonest cause of severe acute respiratory failure in the critically ill. ARDS is a major cause of death and disability in the critically ill worldwide. Second, there is no treatment for ARDS, and our present management approaches are limited to supporting organ function while treating the underlying causes
We performed the LUNG SAFE study to address several clinically important questions regarding ARDS.
First, the current incidence in a large international cohort was not known. Large regional differences had been suggested: for example, the incidence of ARDS in the US was reported to be ten times greater of that in Europe_ENREF_4
Second, we wanted to understand how we manage patients with Acute respiratory distress syndrome in the ‘real world’ situation. Specifically, it was not clear to what extent newer approaches to artificial ventilation, such as reducing the size of the breaths (lower tidal volumes) and keeping the lung pressure positive at all times to minimize collapse (PEEP) were used. The impact of studies showing promise for other measures to improve gas exchange such as turning patients prone during mechanical ventilation, or using neuromuscular blockade, on routine clinical practice in the broader international context was not known.
Third, there were some concerns over the extent of clinician recognition of ARDS. This was an important issue because implementation of the effective therapies may be limited by lack of recognition of ARDS by clinicians. A better understanding the factors associated with ARDS recognition and how this recognition influenced patient management could lead to effective interventions to improve care.
Lastly we wanted to determine the outcome from Acute respiratory distress syndrome in a global cohort of patients.
Medical Research: What are the main findings?
We found that ARDS continues to represent an important public health problem globally, with 10% of ICU patients meeting clinical criteria for ARDS. While there appeared to be some geographic variation, this did not seem as great as previously thought.
An important finding was the under-recognition of Acute respiratory distress syndrome by clinicians, with 40% of all cases not being recognized.
In addition, over one third of patients did not receive protective lung ventilation strategies. The use of other measures to aid gas exchange during artificial ventilation, such as turning the patient into the prone position, or the use of neuromuscular blockade was also quite low.
Of most concern, ARDS continues to have a very high mortality of approximately 40% of patients dying in hospital.