Table 2 Human studies evaluating effects of hyperoxia in the cardiac arrest context
From: Hyperoxia toxicity after cardiac arrest: What is the evidence?
Study (year) | Study period | Patients (n=)/hyperoxia prevalence (%) | Shockable rhythm (%) | Blood gas analysis timing | Hyperoxia definition | In-hospital/hyperoxia mortality (%) | Comparison group | Therapeutic hypothermia | Main outcome measure | In-hospital mortality (OR, 95 % CI) | Poor neurological status (OR, 95 % CI) |
|---|---|---|---|---|---|---|---|---|---|---|---|
Kilgannon (2010) | 2001/2005 | 6326/18 | NA | First PaO2 | >300 mmHg | 56/63 | Normoxia | 6 % <34 °C during first 24 h | In-hospital mortality | 1.8 (1.5–2.2) | ? |
Bellomo (2011) | 2000/2009 | 12,108/10 | NA | Lower PaO2 | >300 mmHg | 58/59 | Normoxia | 33 % <34 °C during first 24 h | In-hospital mortality | 1.2 (1.0–1.5) | ? |
Kilgannon (2011) | 2001/2005 | 4459/NA | NA | Highest PaO2 | Continuous variable | 54/? | Normoxia | 6 % <34 °C during first 24 h | In-hospital mortality | 1.69 (1.56–2.07) | ? |
Janz (2012) | 2007/2012 | 170/about 30 | 61 | Highest PaO2 | Continuous variable | 55/? | Normoxia | 100 % <33 °C | In-hospital mortality | 1.4 (1–2) | 1.48 (1.03–2.13) |
Ihle (2013) | 2007/2011 | 584/6 | 100 | Worst PaO2 | >300 mmHg | 42/47 % | Normoxia | ? | In-hospital mortality | 1.2 (0.52–2.82) | ? |
Nelskyla (2013) | 2008/2010 | 119/41 | 40 | Highest PaO2 | >300 mmHg | 63/59 | Non-hyperoxia | 30 % | Factors associated with hyperoxia exposure | 0.76 (0.36–1.61) | ? |
Spindelboeck (2013) | 2003/2010 | 145/20 | ? | <60 min after CPR | >300 mmHg | ?/? | Non-hyperoxia | ? | Rates of hospital admission | ? | ? |
Vaahersalo (2014) | 2010/2011 | 409/NA | 60 | Mean 24 h PaO2 level | Continuous variable | 45/? | Non-hyperoxia | 71 % | CPC at 12 months | ? | 1 (0.99–1.01) |
Lee (2014) | 2008/2012 | 213/1.1 | 25 | Mean PaO2 in 8 ABG | Quartiles of PaO2 | 29.6/? | PaO2 [116–134] | 100 % <33 °C | In-hospital mortality | 0.65 (0.22–1.85) | 4.22 (1.22–14.58) |
Elmer (2015) | 2008/2010 | 184/36 | 38 | Time spent within each PaO2 level | Continuous variable | 54?/? | Non-hyperoxia | 66 % <33 °C | Survival to hospital discharge | 0.83 (0.69–0.99) per hour | 0.8 (0.3–2.13) |
Helmerhorst (2015) | 2007/2012 | 5258/2.7 | ? | Lowest PaO2/FiO2 in first 24 h | >300 mmHg | 53.9/? | Normoxia | 80 % <34 °C | In-hospital mortality | 1.13 (0.81–1.57) | ? |