A Comparative Study on the Effect of Low-Dose Oral Ketamine and Subcutaneous Ketamine on Post General Anesthesia Delirium and Pain in Children Undergoing Inguinal Hernia Surgery

Objective: Acute pain is a common complication in children undergoing surgery. Acute pain and delirium are associated with agitated behavior, in which there is a risk that the patient causes harm to himself and others. Acute pain and delirium also dissatisfy parents and caregivers during recovery, prolong the recovery and hospitalization, and make more nursing care necessary. Material and Methods: In this study, 90 ASA I children, aged 3-8, and two candidates for elective inguinal hernia surgery were divided into three groups based on a random number table using block size of four. Parental permission was obtained beforehand. In group 1, 1mg/kg of ketamine (3cc) was administered orally. In group 2, 0.5mg/kg of ketamine was administered subcutaneously after the anesthetic induction. In Group 3, or control group, the same amount of normal saline was administered as the placebo, then the surgery got underway. Results: Comparing the administration of oral ketamine, subcutaneous ketamine and normal saline, the study showed that the pain was significantly higher in the placebo group at 30, 60, 90 and 120 minutes. Subcutaneous ketamine resulted in higher delirium at 30, 60, 90 and 120 minutes than the placebo and oral ketamine. Satisfaction of nurses from the patient’s recovery was significantly higher in the oral ketamine group and subcutaneous ketamine group (p=0/007). The need for narcotics in the oral ketamine group and subcutaneous ketamine group was lower than the placebo group (p=0/001). Ketamine administration prolonged the length of stay in the PACU, but it did not increase the frequency of complications such as postoperative nausea and vomiting and laryngospasm or bronchospasm in the two groups during the recovery. Conclusion: In conclusion, the study indicated that oral administration of low-dose ketamine before surgery can reduce pain severity and spare the need for analgesics after surgery.