A Recruitment Maneuver After Apnea Testing Improves Oxygenation and Reduces Atelectasis in Organ Donors After Brain Death

Abstract

Background and PurposeHypoxemia is the main modi able factor preventing lungs from being transplanted from organ donors after brain death (BD). One major contributor to impaired oxygenation in brain-injured patients is atelectasis. Apnea testing (AT), an integral component of BD declaration, promotes atelectasis and can worsen hypoxemia. In this study, we tested whether performing a recruitment maneuver (RM) after AT could mitigate hypoxemia and radiographic atelectasis. MethodsDuring the study period, an RM (PEEP of 15 cm H 2 O for 15 seconds then 30 cm H 2 O for 30 seconds) was performed immediately after AT. We measured PaO 2 before and after RM. The primary outcomes were oxygenation (PaO 2 :FiO 2 ratio, PFR) and the severity of atelectasis (proportion of lung without aeration on CT scans after BD, quanti ed using an image analysis algorithm) in those who became organ donors.Outcomes in RM cases were compared to controls undergoing AT without RM in the two years prior. ResultsRM was performed in 54 cases after AT, with a median immediate increase in PaO 2 of 63 mm Hg (IQR 0-109, p = 0.07). Eighteen RM resulted in hypotension but none were life-threatening. Of this cohort, 37 became organ donors, who were compared with 37 donors who had AT without RM. PFR was higher in the RM group (355 ± 129 vs. 288 ± 127, p = 0.03), and fewer had hypoxemia (PFR < 300: 22% vs. 57%, p = 0.04) at the start of donor management. The RM group showed less radiographic atelectasis (median 6% vs. 13%, p = 0.045). Although there was no difference in lungs transplanted (35% vs. 24%, p = 0.44), both better oxygenation and less atelectasis on arrival were associated with a higher likelihood of lungs being transplanted. ConclusionRM after AT results in immediate improvement in oxygenation and reduces hypoxemia and atelectasis in organ donors after BD. This effect may translate into more lungs being transplanted.