Systematic assessment of advanced respiratory physiology: precision medicine entering real-life ICU?

Excerpt

In this uprising era of precision medicine [1], clinical translation of physiological measurements supporting personalized treatments in the intensive care unit (ICU) is of extreme interest. To this end, respiratory mechanics measurements in patients with acute respiratory distress syndrome (ARDS) might become standard to titrate mechanical ventilation settings [2]. This concept was the driving hypothesis of an interesting article by Lu Chen and colleagues recently published in Critical Care [3]. The authors report implementation into the real-life of the medical-surgical and trauma-neurosurgical ICUs of the Toronto-based St. Michael’s Hospital of a 1-year quality improvement program aimed at measuring advanced respiratory mechanics at the bedside in patients with ARDS. Output was real-time creation of an analytic report with actual patient measures handed to the attending physician and start of a prospective registry for future studies. The program enrolled 62 patients in the first year, all with early ARDS, deeply sedated and often paralyzed, who were switched to protective volume-controlled ventilation with standard settings. Esophageal pressure measure was added to patients with moderate and severe ARDS [4]. Target physiological measurements included in the clinical report and registry were: total positive end-expiratory pressure (PEEP), peak pressure, plateau pressure, intrinsic PEEP, driving pressure, respiratory system compliance, resistance, end-expiratory transpulmonary pressure, end-inspiratory transpulmonary pressure, lung compliance, chest wall compliance, transpulmonary plateau pressure, oxygenation, and hemodynamic response to a 3–5 cmH₂O PEEP change [5], and (de)recruitment obtained at clinical PEEP by an abrupt 10 cmH₂O PEEP decrease [6]. In the present analysis, at first the authors retrospectively looked at whether making these measurements available to the attending physician induced any change in ventilation settings. This was true in 67% of cases with a switch from pressure to volume control and PEEP change as the most frequent adjustments. Secondly, authors assessed whether the changes in ventilation settings ameliorated physiological variables known to be associated with patients’ clinical outcome: oxygenation index improved and plateau and driving pressure decreased. Finally, authors investigated whether the changes in ventilation settings were consistent with the physiological report findings and described how the attending physician introduced PEEP changes consistent with the indications suggested by the physiological assessments. …