Extracorporeal carbon dioxide removal technique improves oxygenation without causing overinflation.

Abstract

Extracorporeal CO2 removal combined with low frequency positive pressure ventilation (ECCO2R-LFPPV) improves gas exchange and decreases peak pressures, respiratory rates, and tidal volumes in animals and in humans. Recent evidence suggests that pulmonary barotrauma results from lung overinflation rather than from high pressures. This study was to test the hypothesis whether ECCO2R-LFPPV could improve gas exchange without causing lung overinflation, despite the use of higher levels of PEEP, when compared with conventional mechanical ventilation. Eleven patients with severe adult respiratory distress syndrome (ARDS) who failed to respond to different modes of mechanical ventilation were treated with ECCO2R-LFPPV. Risk of pulmonary barotrauma was evaluated by static pressure-volume (P-V) curves and dynamic changes in volumes monitored by respiratory inductive plethysmography (Respitrace). ECCO2R-LFPPV PaO2/FIO2 increased from 79 +/- 21 to 207 +/- 108 (p = 0.003). Risk of barotrauma, as shown by the shape of the P-V curve, was present in all patients receiving mechanical ventilation even though most of them were treated with permissive hypoventilation. By contrast, no evidence of persistent lung overinflation could be detected by either static P-V curves or dynamic measurements in nine of 11 patients who were treated by ECCO2R-LFPPV. The two remaining patients had severe airway obstruction because of bleeding, and they remained ventilated with persistent risk of barotrauma. We conclude that ECCO2R-LFPPV improves gas exchange without causing lung overinflation in a majority of patients with ARDS.

Air leaks from the respiratory tract in mechanically ventilated children with severe respiratory disease

“…20 Furthermore, risk of AL, as shown by the shape of the pressure-volume loop, was present in all adult patients with severe ARDS receiving conventional MV. 21 The frequency of AL in children with asthma, bronchiolitis, and pneumonia in this study, compares favorably with that in the literature. Studies in adult patients have shown that although there appears to be a trend toward increased survival after MV in acute asthma, ventilation of critically ill asthmatic patients continues to be associated with significant morbidity, including episodes of AL (20%), 22 and mortality.…”

Extracorporeal Life Support for 100 Adult Patients With Severe Respiratory Failure

“…Other centers have corroborated these results, resulting in 30% to 40% survival from ARF with improved conventional management,7 40% to 50% survival with ECLS, 8 and 50% to 60% survival with the two combined. [9][10][11] Based on our experience with neonatal and pediatric ECMO,12"3 and encouraged by the European results with ECCO2R, we initiated a clinical trial in 1988 consisting of a management protocol for severe ARF that included pressure-controlled inverse ratio ventilation, optimized systemic oxygen delivery, restoration of dry weight, prone positioning, and ECLS. After 2 years of pilot experience and protocol modification, we have followed this standardized approach since 1990.…”

Measurement of overinflation by multiple linear regression analysis in patients with acute lung injury

“…Their plateau pressure commonly exceeded the upper inflection point (80% incidence) when a VT of 10 mL·kg -1 was used; however, this decreased dramatically (0-20% incidence) with VT of 5.5-7 mL·kg -1 . Using impedance plethysmography, BRUNET et al [23,24] also found an upper inflection point in ARDS patients, albeit at generally higher pressures than ROUPIE et al [7]. However, almost half the time this occurred at Paw <30 cmH 2 O.…”