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

Rajat Dhar; Porche Braun; Atul Kumar; Jayesh Patel; Flavia L Lee; Baback Arshi

doi:10.1007/s12028-024-01975-7

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

Neurocrit Care. 2024 Apr 5. doi: 10.1007/s12028-024-01975-7. Online ahead of print.

Authors

Rajat Dhar¹, Porche Braun², Atul Kumar², Jayesh Patel^{2

3}, Flavia L Lee^{2

4}, Baback Arshi²

Affiliations

¹ Department of Neurology, Washington University School of Medicine, 660 S Euclid Avenue, Campus Box 8111, St. Louis, MO, 63110, USA. dharr@wustl.edu.
² Department of Neurology, Washington University School of Medicine, 660 S Euclid Avenue, Campus Box 8111, St. Louis, MO, 63110, USA.
³ Department of Neurology, Drexel University College of Medicine, Philadelphia, PA, USA.
⁴ Department of Neurology, Wake Forest University School of Medicine, Winston-Salem, NC, USA.

PMID: 38580801
DOI: 10.1007/s12028-024-01975-7

Abstract

Background: Hypoxemia is the main modifiable factor preventing lungs from being transplanted from organ donors after brain death. One major contributor to impaired oxygenation in patients with brain injury is atelectasis. Apnea testing, an integral component of brain death declaration, promotes atelectasis and can worsen hypoxemia. In this study, we tested whether performing a recruitment maneuver (RM) after apnea testing could mitigate hypoxemia and atelectasis.

Methods: During the study period, an RM (positive end-expiratory pressure of 15 cm H₂O for 15 s then 30 cm H₂O for 30 s) was performed immediately after apnea testing. We measured partial pressure of oxygen, arterial (PaO₂) before and after RM. The primary outcomes were oxygenation (PaO₂ to fraction of inspired oxygen [FiO₂] ratio) and the severity of radiographic atelectasis (proportion of lung without aeration on computed tomography scans after brain death, quantified using an image analysis algorithm) in those who became organ donors. Outcomes in RM patients were compared with control patients undergoing apnea testing without RM in the previous 2 years.

Results: Recruitment maneuver was performed in 54 patients after apnea testing, with a median immediate increase in PaO₂ of 63 mm Hg (interquartile range 0-109, p = 0.07). Eighteen RM cases resulted in hypotension, but none were life-threatening. Of this cohort, 37 patients became organ donors, compared with 37 donors who had apnea testing without RM. The PaO₂:FiO₂ ratio was higher in the RM group (355 ± 129 vs. 288 ± 127, p = 0.03), and fewer had hypoxemia (PaO₂:FiO₂ ratio < 300 mm Hg, 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 were associated with a higher likelihood of lungs being transplanted.

Conclusions: Recruitment maneuver after apnea testing reduces hypoxemia and atelectasis in organ donors after brain death. This effect may translate into more lungs being transplanted.

Keywords: Brain death; Organ donation.