Conservative oxygen therapy in mechanically ventilated patients following cardiac arrest: A retrospective nested cohort study. (April 2016)

• Record Type: Journal Article
• Authors: Eastwood, Glenn M.; Tanaka, Aiko; Espinoza, Emilo Daniel Valenzuela; Peck, Leah; Young, Helen; Mårtensson, Johan; Zhang, Ling; Glassford, Neil J.; Hsiao, Yu-Feng Frank; Suzuki, Satoshi; Bellomo, Rinaldo
• Is Part Of: Resuscitation. Volume 101(2016)
• Page Start: 108
• Page End: 114
• Publication Date: 2016-04
• Subjects: Oxygen -- Cardiac arrest -- Mechanical ventilation -- Mortality -- Outcome -- Intensive care; Resuscitation -- Periodicals; Resuscitation -- Periodicals; Réanimation -- Périodiques; Electronic journals; 616.025
• DOI: 10.1016/j.resuscitation.2015.11.026
• Languages: English
• ISSNs: 0300-9572

Abstract

Abstract: Background: In mechanically ventilated (MV) cardiac arrest (CA) survivors admitted to the intensive care unit (ICU) avoidance of hypoxia is considered crucial. However, avoidance of hyperoxia may also be important. A conservative approach to oxygen therapy may reduce exposure to both. Methods: We evaluated the introduction of conservative oxygen therapy (target SpO2 88–92% using the lowest FiO2 ) during MV for resuscitated CA patients admitted to the ICU. Results: We studied 912 arterial blood gas (ABG) datasets: 448 ABGs from 50 'conventional' and 464 ABGs from 50 'conservative' oxygen therapy patients. Compared to the conventional group, conservative group patients had significantly lower PaO2 values and FiO2 exposure ( p < 0.001, respectively); more received MV in a spontaneous ventilation mode (18% vs 2%; p = 0.001) and more were exposed to a FiO 2 of 0.21 (19 vs 0 patients, p = 0.001). Additionally, according to mean PaO2, more conservative group patients were classified as normoxaemic (36 vs 16 patients, p < 0.01) and fewer as hyperoxaemic (14 vs 33 patients, p < 0.01). Finally, ICU length of stay was significantly shorter for conservative group patients ( p = 0.04). There was no difference in the proportion of survivors discharged from hospital with good neurological outcome (14/23 vs 12/22 patients, p = 0.67). Conclusions: Our findings provide preliminary support for the feasibility and physiological safety of conservative oxygen therapy in patients admitted to ICU for MV support after cardiac arrest (Trial registration, NCT01684124 ).