Critical care outreach team's effect on patient outcome

Editor—In their paper Ball et al show that the intervention of a critical care outreach team increased survival to discharge and rate of readmissions to critical care.¹ Despite the reduced probability of inhospital mortality in the intervention group of patients, the relative risk ratio was 1.00-1.18; it therefore includes 1 (unless a further figure greater than zero behind the two zeros was omitted) and does not seem to indicate significance (a P value was not published).

The reduction of readmissions by nine patients over 12 months is likely to be explained by a relative increase of survivors in critical care by 34% in the intervention period, with an increase of median length of stay of 0.9 days. Unless the number of critical care beds was increased in the intervention period or the non-survivors died at an earlier stage during their admission, these two figures make the availability of empty beds for readmissions less likely. The increased length of stay in intensive care is also likely to reduce the need for readmission. Multivariate analysis with the number of empty beds per day as a covariable may be able to show this.

The five senior critical care nurses and the nurse consultant participated in many activities other than following up patients discharged from critical care. The real effects of the critical care outreach team may be seen if the quality of care received by patients not admitted to intensive care could be assessed better. However, these data are more difficult to collect and subject to multiple confounding factors.