A Prospective Randomized Trial Comparing Stroke Volume Measurements by Esophageal Doppler and Pulse-Contour Analysis During a Fluid Resuscitation Protocol in Brain-Dead Organ Donors

Abstract

Purpose Maximizing stroke volume (SV) is the optimal method of fluid resuscitation. Both the esophageal doppler (EDM) and pulse contour analysis (PCA) are validated methods of measuring SV in critical patients, but neither have not been well-studied in the brain-dead (BD) donor. We have previously published our fluid resuscitation protocol in BD donors demonstrating a significant reduction in time on vasopressors from 16 hours in the control group to 2.9 hours in the protocol group. We performed a prospective randomized trial comparing the effectiveness of the EDM and PCA in this fluid resuscitation protocol in BD donors. Methods Between April 2018 and March 2019, all brain-dead organ donors requiring a vasopressor in our organ recovery center were eligible for the study. The donor was randomized to either the EDM or PCA group, and the SV was measured every 30 minutes for 4 hours. A 500 ml bolus of normal saline (NS) was infused over 30 minutes at the start of the study. If the SV increased by 10%, the NS bolus was repeated. If the SV did not increase by 10%, no fluid was given for 30 min. If the SV then decreased by 10% after receiving no fluid, then the NS bolus was repeated. The vasopressors were weaned every 10 minutes if the MAP was greater than 65 mm Hg. Vasopressin was only used to control polyuria from diabetes insipidus and not for BP support. All donors received 300 mg IV hydrocortisone and no thyroxine. Results 64 donors were eligible for the study, and 32 donors were randomly assigned to each group. The baseline characteristics of both groups were well-matched for 23 criteria (expected total organs recovered, 3.00 ±1.33 vs 3.28 ±1.41, p=0.41, using the 2017 SRTR calculator). There was no significant difference between the EDM and PCA in the amount of fluid given over 4 hours (mean 1984 ml ±875 vs 1891 ml ±948, p=0.68), the time on vasopressors (mean 188 min ±75 vs 165 min ±89, p=.28), or percent donors off vasopressors in 4 hours (37.5% vs 40.6%, p=0.80). The difference in number of organs recovered per donor between the EDM and PCA was not significant (3.22 ±1.26 vs 3.56 ±1.74, p=0.34). Conclusion The EDM and the PCA were equally effective in measuring the SV in the BD donor during fluid resuscitation and demonstrated clinical equipoise in weaning vasopressors, volume of fluid infused, and organs transplanted. Maximizing stroke volume (SV) is the optimal method of fluid resuscitation. Both the esophageal doppler (EDM) and pulse contour analysis (PCA) are validated methods of measuring SV in critical patients, but neither have not been well-studied in the brain-dead (BD) donor. We have previously published our fluid resuscitation protocol in BD donors demonstrating a significant reduction in time on vasopressors from 16 hours in the control group to 2.9 hours in the protocol group. We performed a prospective randomized trial comparing the effectiveness of the EDM and PCA in this fluid resuscitation protocol in BD donors. Between April 2018 and March 2019, all brain-dead organ donors requiring a vasopressor in our organ recovery center were eligible for the study. The donor was randomized to either the EDM or PCA group, and the SV was measured every 30 minutes for 4 hours. A 500 ml bolus of normal saline (NS) was infused over 30 minutes at the start of the study. If the SV increased by 10%, the NS bolus was repeated. If the SV did not increase by 10%, no fluid was given for 30 min. If the SV then decreased by 10% after receiving no fluid, then the NS bolus was repeated. The vasopressors were weaned every 10 minutes if the MAP was greater than 65 mm Hg. Vasopressin was only used to control polyuria from diabetes insipidus and not for BP support. All donors received 300 mg IV hydrocortisone and no thyroxine. 64 donors were eligible for the study, and 32 donors were randomly assigned to each group. The baseline characteristics of both groups were well-matched for 23 criteria (expected total organs recovered, 3.00 ±1.33 vs 3.28 ±1.41, p=0.41, using the 2017 SRTR calculator). There was no significant difference between the EDM and PCA in the amount of fluid given over 4 hours (mean 1984 ml ±875 vs 1891 ml ±948, p=0.68), the time on vasopressors (mean 188 min ±75 vs 165 min ±89, p=.28), or percent donors off vasopressors in 4 hours (37.5% vs 40.6%, p=0.80). The difference in number of organs recovered per donor between the EDM and PCA was not significant (3.22 ±1.26 vs 3.56 ±1.74, p=0.34). The EDM and the PCA were equally effective in measuring the SV in the BD donor during fluid resuscitation and demonstrated clinical equipoise in weaning vasopressors, volume of fluid infused, and organs transplanted.