Skip to main content

Table 3 Results of the summary effect estimates for the secondary outcomes

From: Intraosseous versus intravenous vascular access during cardiopulmonary resuscitation for out-of-hospital cardiac arrest: a systematic review and meta-analysis of observational studies

Analysis Outcome or moderator variables Number of included studies Odds ratio (95% confidence interval) I2, % p for mixed-effects meta-regression analysis
Main analysis Short-term survival 9 [17,18,19,20,21,22,23,24,25] 0.71 (0.59–0.85) 86 NA
Subgroup analysis
 Study period Before 2010 1 [19] 0.58 (0.48–0.70) 0 0.39
After 2010 8 [17, 18, 20,21,22,23,24,25] 0.73 (0.60–0.89) 87  
 Study region North America 7 [17,18,19,20,21, 23, 25] 0.74 (0.59–0.94) 88 0.36
Europe 2 [22, 24] 0.62 (0.23–1.69) 40  
 Selection of vascular access First attempted vascular access 5 [17, 19,20,21, 25] 0.70 (0.50–0.98) 90 0.90
Actual vascular access 4 [18, 22,23,24] 0.72 (0.49–1.04) 82  
 EMS response time Longer than 10 mins 2 [21, 22] 0.59 (0.09–4.02) 67 0.24
Shorter than 10 mins 7 [17,18,19,20, 23,24,25] 0.75 (0.61–0.92) 87  
 Time to intervention Timing adjusted in analysis 5 [18, 20, 22, 23, 25] 0.77 (0.64–0.92) 76 0.25
Timing not adjusted in analysis 4 [17, 19, 21, 24] 0.64 (0.39–1.05) 85  
 Type of effect estimates pooled in analysis Adjusted effect estimates 6 [18,19,20, 22, 23, 25] 0.73 (0.61–0.88) 82 0.55
Unadjusted effect estimates 3 [17, 21, 24] 0.66 (0.25–1.70) 88  
 Initial arrest rhythm Shockable rhythms 4 [19, 20, 23, 25] 0.72 (0.48–1.09) 80 NA
Main analysis Survival at hospital discharge 7 [18,19,20, 22,23,24,25] 0.66 (0.42–1.04) 89 NA
Subgroup analysis
 Study period Before 2010 1 [19] 0.40 (0.26–0.61) 0 0.31
After 2010 6 [18, 20, 22,23,24,25] 0.72 (0.44–1.19) 88  
 Study region North America 5 [18,19,20, 23, 25] 0.75 (0.47–1.20) 86 0.30
Europe 2 [22, 24] 0.45 (0.0003–521.08) 87  
 Selection of vascular access First attempted vascular access 3 [19, 20, 25] 0.64 (0.24–1.69) 90 0.84
Actual vascular access 4 [18, 22,23,24] 0.68 (0.25–1.85) 87  
 EMS response time Longer than 10 mins 1 [22] 0.76 (0.47–1.23) 0 0.79
Shorter than 10 mins 6 [18,19,20, 23,24,25] 0.64 (0.37–1.13) 92  
 Time to intervention Timing adjusted in analysis 5 [18, 20, 22, 23, 25] 0.83 (0.64–1.08) 66 0.01
Timing not adjusted in analysis 2 [19, 24] 0.34 (0.02–5.91) 31  
 Type of effect estimates pooled in analysis Adjusted effect estimates 6 [18,19,20, 22, 23, 25] 0.75 (0.53–1.07) 81 0.06
Unadjusted effect estimates 1 [24] 0.25 (0.13–0.47) 0  
 Initial arrest rhythm Shockable rhythms 4 [19, 20, 23, 25] 0.78 (0.44–1.41) 80 NA