Identification of separation phenomenon during brain death determination of potential organ donor and analysis of relative factors

Background: With analyzing the incongruent phenomenon of electrical active and cerebral blood flow in brain death determination and screening the related factors, offer correct explanations and countermeasure to ensure the successful implementation of donation after brain death.Methods: Relevant clinical data of potential brain death organ donors were prospectively collected between June 2018 and May 2019. The related parameters of neurological examination, laboratory examination and neuroimaging examination during the period of brain death determination were dynamically recorded. Separation phenomenon was used as grouping factors to screen the factors related to separation phenomena through univariate and multivariate analysis.Results: According to the inclusion criteria, 127 patients were included in the study. Among 22 patients (17.3%) with incongruent phenomenon, 17 (77.3%) had electrical silence earlier than cerebral blood flow arrest, and 9 (22.7%) had cerebral blood flow arrest earlier than electrical silence. Univariate and multivariate analysis showed that age <14 years (OR=6.25, 95%CI 1.21-32.22, p=0.028), SBP≥140 mmHg (OR=7.43, 95%CI 1.62-33.99, p=0.010), primary brainstem injury (OR=15.89, 95%CI 3.04-82.93, p=0.006), spontaneous respiratory arrest time ≤72 hours (OR=11.96, 95%CI 1.59-89.78, p=0.009) and decompression craniotomy(unilateral or bilateral) (OR=16.28, 95%CI 2.25-117.73, p=0.001) were associated with separation phenomenon..Conclusions: Separation phenomenon is a common during the confirmation test of brain death determination in China, and should be correctly recognized. To adopt corresponding measures according to risk factors is useful for successful implementation of donation after brain death.