The Scientific World Journal / 2013 / Article / Tab 3

Clinical Study

Assessment of Pulse Oximeter Perfusion Index in Pediatric Caudal Block under Basal Ketamine Anesthesia

Table 3

Bedside indices for the onset of caudal block: numbers of patients meeting predefined “clinically obvious” targets indicative of onset of caudal block over time.

Pre-defined “clinically obvious” targets for positive test of onset of caudal blockTime after caudal injection (min)Number (%) of patients reaching targets for positive testComparison with rPI for the same dose and time interval

rPI toe (100% change from time 0)517/20 (85%)
1019/20 (95%)
15 20/20 (100%)*
20 20/20 (100%)*
CR (absence %)50/20 (0%)*rPI > CR0% for CR
102/20 (10%)rPI > CR
159/20 (45%)rPI > CR100% for dPI*
2020/20 (100%)rPI = CR100% for dPI, CR
rMAP (15% change from time 0)50/20 (0%)*rPI > rMAP0% for rMAP
101/20 (5%)rPI > rMAP
152/20 (10%)rPI > rMAP100% for dPI*
202/20 (10%)rPI > rMAP100% for dPI*
rHR (15% change from time 0)50/20 (0%)*rPI > rHR0% for rHR
103/20 (15%)rPI > rHR
154/20 (20%)rPI > rHR100% for dPI*
204/20 (20%)rPI > rHR100% for dPI*

PI: perfusion index; CR: cremasteric reflex; HR: heart rate; MAP: mean arterial pressure. Separate contingency tables were constructed to compare rPI with CR (absence %), rPI with rMAP, and rPI with rHR at each time point. Values are number (ratio). *Some contingency tables were so one-sided that they could not be assessed using McNemar’s test of symmetry, as there was either 100% positive data for rPI or 0% positive data for the comparison test. In these cases, the superiority of rPI was clearly self-evident.