Rescue therapy for refractory ARDS should be offered early: yes

Abstract

Clinical vignette A previously healthy 51-year-old woman (height 165 cm, weight 60 kg) was admitted to the ICU with severe community acquired pneumonia. She required intubation and mechanical ventilation 6 h after admission. Her respiratory status declined continuously over the next few hours. Twelve hours after admission, blood gases were as follows: pH = 7.36, PaCO 2 = 47 mmHg, PaO 2 = 65 mmHg, HCO 3 -= 26 mmol/L on FiO 2 = 100 %, Vt set at 340 ml, PEEP at 8 cmH 2 O, respiratory rate at 28/min, and plateau pressure measured at 28 cmH 2 O. She was hemodynamically stable and had a normal renal function.This patient has severe ARDS according to the Berlin definition [1]. This patient has very low respiratory system compliance (18 ml/cmH 2 O) and is ventilated with a high driving pressure (20 cmH 2 O). Hypoxemia is extremely severe with a high oxygenation index (43 cmH 2 O/mmHg). Recent clinical studies showed that hospital mortality in patients experiencing such severe forms of ARDS ranges from 45 to 60 % [1-6].What are the first-line options in this situation?This patient receives only 8 cmH 2 O of PEEP. While higher PEEP confers a survival advantage in severe ARDS patients [7], higher levels of PEEP in this patient very likely will further increase the plateau pressure to levels that are certainly associated with an increased risk of ventilator-induced lung injury. Inhaled nitric oxide might have improved arterial oxygenation although this intervention was not shown to improve long-term survival. On the other hand, prone positioning should be rapidly initiated for more than 16 h since a significant increase in survival [8] has been observed in patients with severe ARDS with this maneuver. This patient should also receive continuous infusion of neuromuscular blockade agents [9].What is the rationale for applying ''ultraprotective'' MV in this situation?Lung hyperinflation occurs in approximately 30 % of ARDS patients ventilated using the protective ARDSNet strategy [10]. Moreover, Hager and co-workers retrospectively analyzing data of the ''ARDSNet'' trial group show a linear relationship between mortality and P plat -a linear relationship in the sense that the lower P plat , the lower the mortality, even for P plat less than 30 cmH 2 O [11]. In a proof of concept study, Terragni et al. [12] demonstrated that very low tidal volume ventilation Intensive Care Med (2015) 41:923-925

The standard of care of patients with ARDS: ventilatory settings and rescue therapies for refractory hypoxemia

“…Severe ARDS is often associated with refractory hypoxemia, and early identification and treatment are mandatory [ 90 ]; however, a “simple” definition of life-threating hypoxemia has not been identified. Specific ventilator settings comprising limitation of tidal volume, adequate high PEEP, a recruitment maneuver (open lung approach) in special situations, I:E ratio = 1:1 with a “balanced” respiratory rate as well as prone position (early and prolonged) are recommended in a specific “timetable” (Fig.…”

Serial Lactate Measurements as a Prognostic Tool in Venovenous Extracorporeal Membrane Oxygenation Support

“…Venovenous extracorporeal membrane oxygenation (VV-ECMO) is a well-established therapy in patients with ARDS unresponsive to conventional therapy [7][8][9], but no data are so far available on the serial measurements of lactate and lactate clearance during VV-ECMO support.…”

Pulmonary vascular dysfunction in refractory acute respiratory distress syndrome before veno‐venous extracorporeal membrane oxygenation

“…Pulmonary vascular dysfunction has been recognized in patients with acute respiratory distress syndrome (ARDS) since 1977, and recently, echocardiography has been used to identify acute cor pulmonale in these patients . Venous‐venous extracorporeal membrane oxygenation (VV‐ECMO) is a well‐established treatment for patients with ARDS unresponsive to conventional therapy . To date, there is a paucity of data on pulmonary vascular dysfunction assessed by echocardiography in these patients.…”