Comparison of Doses of Dexmedetomidine With Bupivacaine in Caudal Block for Duration of Analgesia in Paediatric Infraumblical Surgeries.

Pain is one the most underrated, misunderstood and often underdiagnosed field especially in children. Pain is an unpleasant feeling which is basically a subjective feeling, which in children is poorly expressed. Failure to control pain during childhood ultimately results in having chronic adverse effects which include altered sleep, eating habits and neuroendocrine responses and increased sensitivity to pain in the following pain episodes.

Successful postoperative pain management is one of the main pillars of anaesthesia. Regional Anaesthesia has gained a lot of popularity over the past few years in paediatrics. Approximately one-quarter of analgesic procedures currently performed on children are done by regional analgesic techniques. There are various methods that are being currently used to control post-operative pain among children. Amongst these methods, caudal block is one of the most favoured, prominent and dependable methods for providing reliable analgesia in surgeries below umbilicus. However, it has a drawback of being having a limited time of action when used as a single shot technique. This time limit can be increased significantly by the addition of different adjuvants along with local anaesthetic drugs in caudal block, which not only helps the anaesthesiologist in giving a better quality of anaesthesia and analgesia but it leads up to creating a desirable intraoperative environment for the surgeon as well. Better control over intraoperative and post-operative analgesia also helps the anaesthesiologist in giving reduced levels of anaesthesia which caused reduced amount of postoperative sedation as well.

Dexmedetomidine has a specific affinity for α2-adrenoreceptor having sedative and analgesic properties, which makes it an ideal adjuvant agent. The landmark ability of this adjuvant is that it causes minimal respiratory depression even at high dosages. A number of studies have been done until now that have proved successfully that dexmedetomidine can be used as an adjuvant in caudal block, in children, in enhancing post-operative analgesia. Although there is insufficient data available, various studies have demonstrated the dose of dexmedetomidine in Caudal Block ranging from 0.5 µg/kg to 2 µg/kg. According to an up to date review anaesthesia will last longer with dexmedetomidine as compared to morphine when used, as haemodynamics were found to be stable mostly when dexmedetomidine was used. However bradycardia was mostly related to a dose of 2 mcg/kg of dexmedetomidine. A study published in 2019 documented a decrease in heart rate, not requiring active management, in the dexmedetomidine group at a dose of 1mcg/kg.

Our objective is to compare two doses of Dexmedetomidine added as adjunct to local anaesthesia using reduced dose in caudal block for prolonging the duration of analgesia. Our secondary outcomes will include blood pressure, heart rate, urinary retention, nausea and vomiting in the paediatric population.

Patient meeting inclusion criteria visiting paediatric operating room will be inducted in the study. Informed and written consent will be taken from parents/guardian explained about the potential risk and benefits of study. Patients' demographic details like age, sex, and weight will be collected by filling the relevant proforma. A total of 162 patients will be divided into three equal groups randomly by lottery method. The observer and the anaesthesiologist who will induce the patient will be blinded regarding the group in which the patient will be placed.