Caudal Block with bupivacaine tied to insignificant decrease in Cardiac Index During Minor Surgeries: Study

Caudal blockade is frequently used in pediatric anesthesia as it is considered safe and offers sufficient pain relief during the perioperative period for surgeries below the umbilicus and on the lower limbs. The impact on cardiovascular function of neuraxial blocks is typically milder in children compared to adults due to various factors. Recent study aimed to investigate the impact of caudal block with varying volumes of plain bupivacaine 0.25% on the cardiac index in children undergoing minor lower abdominal surgeries. Children aged 1–8 years were divided into three groups: the 0.8 group received general anesthesia (GA) with a caudal block using 0.8 mL/kg of bupivacaine 0.25%, the 1.2 group received GA with 1.2 mL/kg of bupivacaine 0.25%, and the control group received GA alone. The primary outcome was the percentage change in the cardiac index from baseline 10 minutes after the caudal block.

Results showed that the mean percentage change in the cardiac index from baseline was significantly lower in the 0.8 and 1.2 groups compared to the control group. The decrease in the cardiac index continued for up to 30 minutes after the caudal block. The absolute values of the cardiac index significantly dropped after the caudal block in both the 0.8 and 1.2 groups, with the 1.2 group showing lower values compared to the control group at certain time points.

Dose-Dependent Effects

The study identified a dose-dependent effect of the caudal block with plain bupivacaine on the cardiac index, with increasing volumes leading to a progressive decrease. Despite the statistically significant drop, the cardiac index remained within an acceptable range after the caudal block. However, caution is advised due to the increased incidence of hypotension with higher volumes of local anesthetics in the caudal block.

Impact on Cardiac Index

The findings suggested that the decrease in the cardiac index could be attributed to an impairment in autonomic regulation, resulting in reduced heart rate and cardiac contractility. The study utilized electrical cardiometry to assess the cardiac index, providing non-invasive monitoring with reasonable accuracy in pediatric anesthesia settings.

Limitations

Limitations of the study included its single-center design, lack of central venous pressure monitoring, and measurement duration restricted to 30 minutes post-caudal block. Despite these limitations, the results highlighted the importance of monitoring cardiac parameters during caudal blocks in children to ensure hemodynamic stability. In conclusion, the study demonstrated that the cardiac index decreases progressively with increasing volumes of plain bupivacaine in caudal blocks but remains clinically acceptable. Monitoring for hypotension is crucial with larger volumes of local anesthetics. Further research is warranted to explore the mechanisms underlying the observed changes in cardiac parameters during caudal blocks in pediatric patients undergoing minor lower abdominal surgeries.

Key Points

- Investigated impact of caudal block with different volumes of plain bupivacaine 0.25% on cardiac index in children undergoing minor lower abdominal surgeries.

- Divided children aged 1–8 years into three groups: 0.8 mL/kg bupivacaine group, 1.2 mL/kg bupivacaine group, and control group.

- Found significantly lower mean percentage change in cardiac index in bupivacaine groups compared to control group post-caudal block, with decrease continuing up to 30 minutes.

- Noted dose-dependent effect of caudal block with bupivacaine on cardiac index, leading to a progressive decrease with increasing volumes.

- Suggested decrease in cardiac index due to autonomic regulation impairment, impacting heart rate and cardiac contractility, monitored using electrical cardiometry.

- Highlighted importance of monitoring cardiac parameters during caudal blocks in children for hemodynamic stability, emphasizing need for further research on observed cardiac changes.

Reference –

K. Sarhan et al. (2025). Effect Of Different Volumes Of Bupivacaine 0.25% Caudal Blocks On Cardiac Index Measured By Electrical Cardiometry In Children Undergoing Elective Lower Abdominal Surgeries: A Randomised Controlled Trial. *Indian Journal Of Anaesthesia*.https://doi.org/10.4103/ija.ija_858_24