Efficacy of bupivacaine infiltration for post-operative pain relief in paediatric patients

 

 

 

 

 

Abstract               Background: The effective control of pain remains one of the most important issues in the postoperative care today. Local infiltration of bupivacaine requires less skill and is better technique for postoperative pain relief in paediatric patients. Aim: To study the efficacy of subcutaneous infiltration of bupivacaine hydrochloride (2mg/kg) for postoperative pain relief in paediatric patients undergoing minor surgeries. Material and Methods: A total of 70 patients were equally distributed in two groups as Group I: patients in which wound was infiltrated with bupivacaine hydrochloride at the end of surgery and Group II: patients in which wound was not infiltrated. Assessment of pain was done by simple linear analogue pain diagram of facial expression, by pain score assessed by parents and visual analogue scale. Results: The group I patient had more duration of analgesia (238.28±49.31 mins/ 243.42±41.01 mins) and group II had less duration of analgesia (39.14±15.41 mins/ 40.0±14.95 mins).The difference of analgesia was significant (p<0.05). Conclusion: Subcutaneous infiltration of wound with bupivacaine for postoperative analgesia is a simple technique and useful to provide analgesia up to 4-5 hours. It is safe and effective method for postoperative analgesia in paediatric patients.

Key Words: Children, bupivacaine, subcutaneous infiltration, analgesia.

 

 

INTRODUCTION

Pain is an unpleasant sensory and emotional experience associated with actual and potential tissue damage. The effective control of pain remains one of the most important issues in the postoperative care today. The problems of postoperative pain in paediatric patients are different as compared to the adults as communication is difficult and moreover there is a hesitation on the part of doctors and nurses to administer drugs in paediatric patients, so effective postoperative pain relief is inadequate.¹ Bupivacaine is often administered by epidural injection during spinal anesthesia. It is also commonly injected into surgical wound sites for the relief of postoperative pain.² Local infiltration of bupivacaine requires less skill and sophisticated equipments. Hence, this is better technique for postoperative pain relief in paediatric patients. The present study was undertaken to study the efficacy of subcutaneous infiltration of bupivacaine hydrochloride (2mg/kg) for postoperative pain relief in paediatric patients undergoing minor surgeries.

 

MATERIAL AND METHODS

In this prospective study, patients between 1-12 years of age undergoing surgery for congenital tallipusequinovarus, post-polio and post-traumatic contractures, hernia, hydrocele and bladder stone were included. Informed consent of parent of each child was obtained. Patients presenting with upper respiratory tract infections, history of convulsions, liver, heart diseases, allergic reactions and bleeding disordersand undergoing major surgery were excluded from the study. A total of 70 patients were equally distributed in two groups as Group I: patients in which wound was infiltrated with bupivacaine hydrochloride at the end of surgery and Group II: patients in which wound was not infiltrated. All the included patients were not premedicated and operated under general anaesthesia. Induction was done with thiopentone sodium (2-5 mg/kg) or ketamine (2 g/kg). Intubation was done under the effect of suxamethonium chloride (2 mg/kg). Maintenance was done with oxygen + halothane + pancuronium bromide. Vital parameters were monitored continuously. No analgesics were given intraoperatively. At the end of the surgery, subcutaneous infiltration of incisional wound with bupivacaine hydrochloride (2 mg/kg) was done in 35 children (Group I). The dilution of bupivacaine was done according to length of incision. In remaining 35 patients (Group II), wound was not infiltrated with bupivacaine. The patients were decurarised with neostigmine (0.04 mg/kg) and atropine (0.01 mg/kg). Local antibiotics were not applied after closure of wound. Every patient was observed in recovery room for one hour as the peak level after infiltration of bupivacaine reach at 10.4 minutes. Duration of analgesia was noted as time from infiltration of drug till child starts complaining of severe pain or cries due to pain. Assessment of pain in children of age group 1-5 years was done by simple linear analogue pain diagram of facial expression, by vital parameters and with the help of pain score assessed by parents and was represented in their own words. Assessment of pain in children of age group 6-12 years was done by objective and subjective methods. In objective method, vital parameters such as pulse rate and respiratory rate were used. Subjective assessment was done with the help of visual analogue scale. Assessment of pain was carried out at 0 minutes, 20 minutes, 30 minutes, 40 minutes, 60 minutes, 2 hrs, 4 hrs, 5 hrs and 6 hrs after infiltration of drug till the pain became very severe.

 

RESULTS

In present study, a total of 70 patients were equally distributed in two groups as Group I: patients in which wound was infiltrated with bupivacaine hydrochloride at the end of surgery and Group II: patients in which wound was not infiltrated. Average age of the patients in group I was 3.85±3.46yrs and in group II was 4.21±2.28 yrs. Most of the patients were males. Both the groups were comparable as far as the basic characteristics and surgical procedures were considered.

 

Table 1: Characteristics of the study population

In group I and II difference of analgesia was significant p<0.05, i.e., the group I patient had more duration of analgesia (238.28±49.31 mins/ 243.42±41.01 mins) and group II had less duration of analgesia (39.14±15.41 mins/ 40.0±14.95 mins). The analgesia up to 40 minutes in group II might be due to residual effect of anaesthetic agent. The drug had analgesic effect up to 4-5 hours.

 

Table 2: Average duration of analgesia with VAS/LAPD and global assessment

The complications like convulsion, sedation, bradycardia, unconsciousness and delayed complications such as gaping, infection and bleeding were not observed in the present study.