Adequacy of hand positioning by medical personnel during chest compression in a simulation study

Abstract

During chest compressions (CCs), the hand position at the lower half of the sternum is not strictly maintained, unlike depth or rate. This study was conducted to determine whether medical staff could adequately push at a marked location on the lower half of the sternum, identify where the inappropriate hand position was shifted to, and correct the inappropriate hand position.Methods: This simulation-based, prospective single-center study enrolled 44 medical personnel. Pressure and hand position during CC were ascertained using a flexible pressure sensor. The participants were divided into four groups by standing position and the hand in contact with the sternum: right-left (R-l), right-right (R-r), left-right (L-r), and left-left (L-l). We compared the groups and the methods: the manual method (MM), the thenar method, and the hypothenar method (HM).Results: Among participants using the MM, 80% did not push adequately at the marked location on the lower half of the sternum; 60%-90% of the inadequate positions were shifted to the hypothenar side. CCs with the HM facilitated stronger pressure, and the position was minimally shifted to the hypothenar side.Conclusion: Medical staff could not push at an appropriate position during CCs. Resuscitation courses should be designed to educate personnel on the appropriate position for application of maximal pressure while also evaluating the position during CCs.

Adequacy of compression positioning using the feedback device during chest compressions by medical staff in a simulation study

“…Therefore, the rescuers pushed the human patient or manikin with a narrower area of the hand than the total contact area of the CPR-Assist ™ during CCs, which might have caused the inadequate compression position more clearly. This could be why the ratio of adequate compression positions using the feedback device in this study was higher than that in the manual CCs reported in the previous study [14].…”

“…In this study, we found that the inadequate compression position occurred in the hypothenar side in the R-r and L-l subgroups, which poses a risk of pushing on the xiphoid that increases the risk of abdominal trauma, such as liver injury [20]. This result was similarly achieved by manual CCs [14] and the participants might have used the feedback device to deliver CCs resulting in the same sensation to manual CCs. Furthermore, if the plane compressed the thenar and hypothenar sides, the ligaments in between would be subjected to force, which could cause damage [18,19].…”

“…In other studies that also used a flexible capacitive sensor [14,17], only approximately 30% of the medical staff or ambulance crew could deliver manual CCs at the adequate position without a feedback device. Most of the Fig.…”

“…The front label indicates the base side of the hand in contact with the CPR-Assist ™ , whereas the back label indicates the tip side of the finger; the thenar and hypothenar label indicate the thenar and hypothenar side of the hand, respectively. B The inset table shows the primary outcomes, namely the frequency of adequate compression positioning where the maximal average pressure was applied to the sensor for each participant, the location where the inadequate position occurred in, and the frequency of each inadequate position rescuers pushed the sternum with the hypothenar side of their wrist joints when the hand was in dorsiflexion [14,15,18,19]. Since the rescuers deliver manual CCs on soft tissues, such as skin and subcutaneous tissues in humans, and on soft materials, such as silicone, when simulating the human skin texture on manikins, it is likely that rescuers can only push with the hypothenar side of their hand at pinpoint.…”

“…The flexible sensor (total sensor size: 5 × 5 cm 2 ) included 25 pressure sensors (one sensor size: 1 × 1 cm 2 ). We assigned the adequate position as 3 × 3 cm 2 area, which was the centre of the flexible sensor as previously reported [14].…”