Arterial Doppler Ultrasound Blood Flow Waveforms During Chest Compressions to Detect Arterial Line Pulsatility.

Abstract

Doppler ultrasound blood flow waveforms during active chest compressions are unique and may allow identification of return of spontaneous circulation. We assessed diagnostic accuracy of 4 identified Doppler ultrasound blood flow waveforms-(1) bidirectional blood flow, (2) minimal blood flow, (3) anterograde dominant blood flow, and (4) pulsatility through compressions-during chest compressions to detect arterial line (a-line) pulsatility during a subsequent pulse check. Secondarily, we assessed if pulsatility through compressions was associated with higher systolic blood pressure (SBP) at pulse check than anterograde dominant blood flow. We conducted a retrospective, diagnostic accuracy study on a prospectively collected convenience sample of adult, emergency department cardiac arrest patients. All patients had a femoral a-line. Prior to a pulse check, Doppler ultrasound clips of the femoral artery were saved and reviewed. During a pulse check, the presence or absence of an arterial line waveform and the highest SBP were recorded. Accuracy, sensitivity, and specificity of the blood flow waveforms were calculated using generalized estimating equation models. Forty-four patients with 123 Doppler ultrasound waveforms and subsequent pulse checks were analyzed. Accuracy of the Doppler ultrasound waveforms was 88.9% (95% confidence interval [CI] 81.3 to 93.7), sensitivity of pulsatility through compressions or anterograde dominant blood flow to detect a-line pulsatility was 97.7% (95% CI 87.7 to 99.6), and specificity of bidirectional blood flow or minimal blood flow for the absence of a-line pulsatility was 81.5% (95% CI 69.3 to 89.6). Estimated least-squares mean SBP was higher (50.9 mmHg [95% CI 25.6 to 76.1 mmHg]) for pulsatility through compressions than anterograde dominant blood flow waveforms. Arterial Doppler ultrasound waveforms during chest compressions had good diagnostic test characteristics for detecting arterial line pulsatility at subsequent pulse check.