The effect of the head-up position on cardiopulmonary resuscitation: a systematic review and meta-analysis

Table 1 The characteristics of the included studies

Study, year	Design	Species	Sample size	No-flow time	CPR method	Head-up angle	CPR time
Debaty et al. [15]	Non-RCT	Female Yorkshire farm pigs	22	6 min	LUCAS 2.0 + ITD CPR	− 30°–50°^a	22 min
Ryu et al. [18]	RCT	Female Yorkshire farm pigs	30	8 min	CCPR, ACD + ITD CPR^c	0° and 30°	22 min
Kim et al. [16]	Non-RCT	Female pigs	12	6 min	LUCAS 2.0 + ITD CPR	− 60°–60°^a	18 min
Moore et al. [17]	RCT	Female Yorkshire farm pigs	18	8 min	ACD + ITD CPR^c	0° and 30°	20 min
Putzer et al. [28]	RCT	Domestic pigs	20	8 min	LUCAS 2.0 CPR	0° and 30°	20 min
Moore et al. [14]	Non-RCT	Female Yorkshire farm pigs, pig cadaver, human cadaver	27^b	6 min	CCPR, ACD + ITD CPR^cd	0° and 30°	26 min
Park et al. [22]	RCT	Female Yorkshire farm pigs	18	15 min	LUCAS 2.0 + ITD CPR	0° and 30°^a	6 min

RCT randomized controlled trial, ACD active compression–decompression, CPR cardiopulmonary resuscitation, ITD impedance threshold device, CCPR conventional cardiopulmonary resuscitation
^aA negative number represents the Trendelenburg position, and a positive number represents the reverse-Trendelenburg position
^bIncludes 9 human cadavers
^cUse of a customized animal ACR-CPR machine
^dUse of a manual ACD pump + ITD (ResQPump) on human cadavers

ISSN: 1364-8535