Related Experiment Video
Updated: Aug 10, 2025
Author Spotlight: Simulating Pediatric Cardiac Surgery Using a Neonatal Piglet Model
Published on: May 26, 2023
Perfusion index as a predictor of working pediatric caudal block under general anesthesia- A prospective
Karthika Rajan1, Nandini Dave2, Raylene Dias3
1Senior Resident, Department of Paediatric Anaesthesiology, Seth GS Medical College and KEM Hospital, Mumbai, India.
Insights
Perfusion index (PI) is a better indicator of pediatric caudal block effectiveness than heart rate or mean arterial pressure. This pulse oximetry parameter helps assess block onset and adequacy during general anesthesia.
Area of Science:
- Anesthesiology
- Pediatric Anesthesia
- Regional Anesthesia
Background:
- Pulse oximetry technology allows measurement of perfusion index (PI).
- The utility of lower limb PI for evaluating pediatric caudal block under general anesthesia requires investigation.
- Assessing the onset and adequacy of caudal blocks is crucial for patient safety.
Purpose of the Study:
- To monitor perfusion index (PI) trends after pediatric caudal block.
- To compare PI, heart rate (HR), and mean arterial pressure (MAP) in detecting caudal block onset and adequacy.
- To determine if PI is an earlier indicator of adequate caudal block.
Main Methods:
- Twenty-five children (1-6 years) undergoing general anesthesia with caudal block were studied.
- PI, HR, and MAP were recorded pre- and post-caudal block at various intervals.
- Onset of adequate block was defined by specific increases/decreases in PI, HR, or MAP.
Main Results:
- PI increased significantly in 23/25 patients with a working caudal block (P < 0.0001).
- A 100% increase in PI was observed by 10 minutes in patients with an effective block.
- Significant decreases in HR and MAP were less consistently observed and occurred later than PI changes.
Conclusions:
- Perfusion index (PI) is an earlier and more sensitive indicator of caudal block onset and adequacy compared to HR and MAP.
- PI monitoring offers a valuable tool for assessing regional anesthesia effectiveness in pediatric patients.
- This study supports the use of PI in optimizing pediatric caudal block management.
Background And Aims:
Advances in pulse oximeter technology have enabled us to measure parameters such as perfusion index (PI). We aimed to ascertain the utility of PI in the lower limb for evaluating the onset and adequacy of the pediatric caudal block under general anesthesia. The primary objective was to monitor PI trends after caudal block. The secondary objective was to compare the role of PI, heart rate (HR), and mean arterial pressure (MAP) in detecting onset and adequacy of caudal block and to ascertain whether PI was an earlier indicator in detecting adequate block.
Material And Methods:
Twenty-five children between 1 and 6 years, who underwent general anesthesia (GA) with caudal block were included. Baseline PI, HR, and MAP were recorded prior to and post caudal block at 5, 10, 15, 20 min and on skin incision. The onset of adequate block was defined as 100% increase of PI from baseline, 15% decrease of MAP or HR from baseline. T-test was used to compare trends of PI with baseline and the number of patients who met or failed these criteria for each of these three parameters at various time intervals wasnoted.
Results:
PI increased at all time intervals in 23 of 25 patients with working caudal block (P < 0.0001). By 10 min all those with a working caudal showed a 100% increase in PI. In contrast, 15% decrease in HR was not attained until 15 min where only 8 out of 23 achieved the above criteria, reaching a maximum of 20 patients at the time of incision; a 15% decrease in MAP was observed only in one patient at 5 min, reaching a maximum of eight patients at the time of incision.
Conclusion:
PI is an earlier and more sensitive indicator of the onset of the caudal block under general anesthesia (GA) than HR and MAP.
