A new method to predict return of spontaneous circulation by peripheral intravenous analysis during cardiopulmonary resuscitation: a rat model pilot study

Abstract

Background: Enhancing venous return during cardiopulmonary resuscitation (CPR) can lead to better hemodynamics and improved outcome after cardiac arrest (CA). Peripheral Intravenous Analysis (PIVA) provides feedback on venous flow changes and may indicate an increase in venous return and cardiac output during CPR. We hypothesize PIVA can serve as an early indicator of increased venous return, preceding end-tidal CO₂ (etCO₂) increase, before the return of spontaneous circulation (ROSC) in a rat model of CA and CPR.

Results: Eight male Wistar rats were intubated and ventilated, and etCO₂ was measured. Vessels were cannulated in the tail vein, femoral vein, femoral artery, and central venous and connected to pressure transducers. Ventilation was discontinued to achieve asphyxial CA. After 8 min, CPR began with ventilation, epinephrine, and automated chest compressions 200 times per minute until mean arterial pressure increased to 120 mmHg. Waveforms were recorded and analyzed. PIVA was calculated using a Fourier transformation of venous waveforms. Data are mean ± SE. Maximum PIVA values occurred in the tail vein 34.7 ± 2.9 s before ROSC, with subsequent PIVA peaks in femoral vein and centrally at 30.9 ± 5.4 and 25.1 ± 5.0 s, respectively. All PIVA peaks preceded etCO₂ increase (21.5 ± 3.2 s before ROSC).

Conclusion: PIVA consistently detected venous pressure changes prior to changes in etCO₂. This suggests that PIVA has the potential to serve as an important indicator of venous return and cardiac output during CPR, and also as a predictor of ROSC.

Keywords: End-tidal CO2; Fourier transformation; Monitoring; Murine; PEA; PIVA; Quality; Waveform analysis.

Fig. 1

Exemplary visualization of PIVA, venous pressure, and vital parameters during CPR. Representative image of a peripheral venous waveform amplitude in the tail vein (green), along with the corresponding PIVA values (red), in context with blood pressure (blue) and etCO₂ (black) over the time course of CPR. The maximum venous amplitude is indicated by the red arrow

Fig. 2

Timing of PIVA and ROSC. Timing of PIVA peaks of tail vein, femoral vein, and central venous pressure to etCO₂ in relation to ROSC/end of chest compressions. Data are mean ± SE, * Tail vein vs. etCO₂ p = 0.03