Comparison of Ketamine, Clonidine, and Fentanyl as Anesthetics in the Pediatric Population: A Review of Literature

Abstract

This literature review examines the evidence on the safety profile and effectiveness of various adjuncts, such as clonidine, fentanyl, and ketamine, in pediatric anesthesia. Several studies were reviewed to evaluate the duration and quality of analgesia provided by these adjuncts, as well as their adverse effects. The results showed that adding clonidine to bupivacaine significantly prolonged the mean duration of analgesia compared to the fentanyl and clonidine groups. Children in the clonidine group also experienced lower pain scores and required fewer rescue medications. Furthermore, clonidine exhibited a higher safety margin with a lower incidence of adverse effects, such as urinary retention and pruritus, compared to other adjuncts. Regarding comparisons between fentanyl and clonidine, intrathecal fentanyl resulted in a better hemodynamic profile but required more propofol for sedation. On the other hand, intrathecal clonidine provided a more favorable sedation level. Adverse events like respiratory obstruction and apnea were more likely associated with deep sedation caused by propofol rather than the specific properties of clonidine or fentanyl. In terms of ketamine versus clonidine, caudal blocks using ketamine were found to prolong postoperative anesthesia, particularly for lower limb and abdominal surgeries. When comparing the duration of caudal analgesia achieved by bupivacaine combined with different adjuncts, ketamine exhibited a longer duration compared to clonidine and adrenaline. However, ketamine use was found to be linked with a greater incidence of adverse effects, including urinary retention and pruritus. In conclusion, clonidine demonstrated a relatively higher safety margin with prolonged analgesic effects in pediatric anesthesia compared to fentanyl and ketamine. Its addition to local anesthetics resulted in extended analgesia duration and reduced rescue medication requirements without significant side effects. However, careful monitoring is necessary to manage potential adverse effects.