Brain death determination in patients with veno-arterial extracorporeal membrane oxygenation: A systematic study to address the Harlequin syndrome.

PURPOSE: The Harlequin syndrome may occur in patients treated with venoarterial extracorporal membrane oxygenation (VA-ECMO), in whom blood from the left ventricle and the ECMO system supply different parts of the body with different paCO2-levels. The purpose of this study was to compare two variants of paCO2-analysis to account for the Harlequin syndrome during apnea testing (AT) in brain death (BD) determination. MATERIALS AND METHODS: Twenty-seven patients (median age 48 years, 26-76 years; male n = 19) with VA-ECMO treatment were included who underwent BD determination. In variant 1, simultaneous arterial blood gas (ABG) samples were drawn from the right and the left radial artery. In variant 2, simultaneous ABG samples were drawn from the right radial artery and the postoxygenator ECMO circuit. Differences in paCO2-levels were analysed for both variants. RESULTS: At the start of AT, median paCO2-difference between right and left radial artery (variant 1) was 0.90 mmHg (95%-confidence intervall [CI]: 0.7-1.3 mmHg). Median paCO2-difference between right radial artery and postoxygenator ECMO circuit (variant 2) was 3.3 mmHg (95%-CI: 1.5-6.0 mmHg) and thereby significantly higher compared to variant 1 (p = 0.001). At the end of AT, paCO2-difference according to variant 1 remained unchanged with 1.1 mmHg (95%-CI: 0.9-1.8 mmHg). In contrast, paCO2-difference according to variant 2 increased to 9.9 mmHg (95%-CI: 3.5-19.2 mmHg; p = 0.002). CONCLUSIONS: Simultaneous paCO2-analysis from right and left distal arterial lines is the method of choice to reduce the risk of adverse effects (e.g. severe respiratory acidosis) while performing AT in VA-ECMO patients during BD determination.

Performance of chest compressions with the use of a new audio-visual feedback device: a randomized manikin study in health care professionals.

AIM: Optimal depth (50-60mm) and rate (100-120min(-1)) of chest compressions (CC) is the prerequisite of effective cardiopulmonary resuscitation (CPR). However, insufficient CC during CPR are common even among health care professionals. We sought to evaluate if CC are more effective with the use of a novel feedback device compared to standard CC. Primary endpoints were absolute percentage of correct CC of all CC (correct rate and correct depth, classified as "optimal" CC), and the percentage of CC in target rate and percentage of CC in target depth. METHODS: 63 healthcare professionals performed CC on a manikin with the use of a novel feedback device. The device provides audio-visual information about compression depth and rate. Each participant performed two minutes of CC with and without feedback. Participants were randomized into two groups that performed either CC with feedback first, followed by a trial without feedback, or vice versa. All participants answered a short questionnaire on self-estimation of CC performance. RESULTS: The absolute percentage of optimal compressions of all compressions has increased from 27.9±28.8% to 47.6±33.5% (p<0.001) with use of the device. Furthermore, a significant increase of the percentage of CC in target depth (35.9±30.6% without vs. 54.8±33.5% with the device, p=0.003) and in target rate (70.5±37.7% without vs. 82.7±27.8 with the device, p=0.039) were observed. CONCLUSION: This novel feedback device significantly improved the quality of CC in health care professionals.