Related Experiment Video
Updated: May 26, 2026

Standardized Model of Ventricular Fibrillation and Advanced Cardiac Life Support in Swine
Published on: January 30, 2020
Prevalence and hemodynamic effects of leaning during CPR
Dana E Niles1, Robert M Sutton, Vinay M Nadkarni
1Center for Simulation, Advanced Education and Innovation, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA. niles@email.chop.edu
Background:
Cardiopulmonary resuscitation (CPR) guidelines recommend complete release between chest compressions (CC).
Objective:
Evaluate the hemodynamic effects of leaning (incomplete chest wall release) during CPR and the prevalence of leaning during CPR.
Results:
In piglet ventricular fibrillation cardiac arrests, 10% and 20% (1.8 kg and 3.6 kg, respectively), leaning during CPR increased right atrial pressures, decreased coronary perfusion pressures, and decreased cardiac index and left ventricular myocardial blood flow by nearly 50%. In contrast, residual leaning of a 260 g accelerometer/force feedback device did not adversely affect cardiac index or myocardial blood flow. Among 108 adult in-hospital CPR events, leaning ≥ 2.5 kg was demonstrable in 91% of the events and 12% of the evaluated CC. For 12 children with in-hospital CPR, 28% of CC had residual leaning ≥ 2.5 kg and 89% had residual leaning ≥ 0.5 kg.
Conclusions:
Leaning during CPR increases intrathoracic pressure, decreases coronary perfusion pressure, and decreases cardiac output and myocardial blood flow. Leaning is common during CPR.
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Cardiopulmonary Resuscitation IV: Pharmacological Management
Measurement of Blood Pressure
Special considerations while measuring blood pressure
Monitoring Both Arms:
Monitoring BP in both arms during the initial assessment is advisable, as the systolic value may differ by five to ten mm Hg between arms. For subsequent BP assessments, use the arm with the higher reading.

