Table 2.
Survival to hospital admission by patient and cardiac arrest characteristics by progressively more adjusted regression model
| Unadjusted model | Adjusted for patient and arrest characteristics | Adjusted for patient and arrest characteristics with rhythm interaction | |
|---|---|---|---|
| Risk ratio (95% CI) | Risk ratio (95% CI) | Risk ratio (95% CI) | |
| Exposure | |||
| Calcium given | 0.74 (0.66 – 0.83) | 0.74 (0.66 – 0.82) | |
| Calcium given in shockable rhythm | 0.60 (0.50 – 0.72) | ||
| Calcium given in non-shockable rhythm | 0.87 (0.76 – 0.99)* | ||
| Age | 1.00 (0.99 – 1.00)** | 1.00 (0.99 – 1.00) | |
| Sex | |||
| Female | -- | -- | |
| Male | 1.04 (0.94 – 1.14) | 1.04 (0.95 – 1.15) | |
| Witnessed status | |||
| Unwitnessed arrest | -- | -- | |
| Witnessed arrest | 1.24 (1.11 – 1.38) | 1.24 (1.11 – 1.38) | |
| Initial cardiac rhythm | |||
| Shockable rhythm | -- | ||
| Not shockable rhythm | 0.99 (0.91 – 1.09) |
Risk ratios are presented as risk of survival to hospital admission for patients receiving calcium compared to those that do not receive calcium. Risk ratios greater than 1 represent a protective association for calcium and risk ratio less than 1 represent a harmful association.
*
upper limit of 95% CI is 0.999.
**
lower limit of 95% CI is 0.998. 95% CI = 95% confidence interval.