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Updated: Mar 26, 2026

Ultrasonographic Assessment During Cardiopulmonary Resuscitation
Published on: October 24, 2020
Training a Chest Compression of 6-7 cm Depth for High Quality Cardiopulmonary Resuscitation in Hospital Setting: A
Jaehoon Oh1, Tae Ho Lim2, Youngsuk Cho3
1Department of Emergency Medicine, College of Medicine, Hanyang University, Seoul, Korea.
Purpose:
During cardiopulmonary resuscitation (CPR), chest compression (CC) depth is influenced by the surface on which the patient is placed. We hypothesized that training healthcare providers to perform a CC depth of 6-7 cm (instead of 5-6 cm) on a manikin placed on a mattress during CPR in the hospital might improve their proper CC depth.
Materials And Methods:
This prospective randomised controlled study involved 66 premedical students without CPR training. The control group was trained to use a CC depth of 5-6 cm (G 5-6), while the experimental group was taught to use a CC depth of 6-7 cm (G 6-7) with a manikin on the floor. All participants performed CCs for 2 min on a manikin that was placed on a bed 1 hour and then again 4 weeks after the training without a feedback. The parameters of CC quality (depth, rate, % of accurate depth) were assessed and compared between the 2 groups.
Results:
Four students were excluded due to loss to follow-up and recording errors, and data of 62 were analysed. CC depth and % of accurate depth were significantly higher among students in the G 6-7 than G 5-6 both 1 hour and 4 weeks after the training (p<0.001), whereas CC rate was not different between two groups (p>0.05).
Conclusion:
Training healthcare providers to perform a CC depth of 6-7 cm could improve quality CC depth when performing CCs on patients who are placed on a mattress during CPR in a hospital setting.

