European Journal of Molecular & Clinical Medicine

Abstract

Background: Femoral 3-in-1 nerve block (FNB) alone is frequently used for pain control after total knee replacement (TKR), as the following nerves are inconsistently anesthetized during a Femoral three-in-one block i.e., the Lateral cutaneous nerve (LCN) of the thigh, the Femoral nerve (FN) and the anterior branch of the Obturator nerve (ON). But does not provide complete postoperative analgesia as the posterior branch of the Obturator nerve (ON) and femoral branch of the genitofemoral nerve are not blocked. The intact sensation in the back of the knee after an FNB alone could be attributable to either the obturator or the sciatic nerve, which also supplies the knee joint ^{[2, 5]}.
Objective: The study aims to compare the quality of postoperative analgesia and the need for opioids postoperatively between femoral 3-in-1 nerve block and obturator nerve block added to the femoral 3-in-1 nerve block in patients undergoing elective total knee replacement surgeries.
Materials and Methods: After obtaining the institutional ethics committee approval and patient consent, a Comparative study was conducted on 60 patients aged between 40 and 60 years of ASA I & II scheduled for elective total knee replacement surgeries in MAMATA GENERAL HOSPITAL for 1 year. Patients are randomized into Group 1 (30 patients) which receives a Femoral 3-in-1 nerve block & Group 2 (30 patients) which receives an Obturator nerve block plus a Femoral 3-in-1 nerve block. Patients’ baseline vitals were recorded, after giving the block & the extent of both blocks was evaluated 30 min after injection of the anesthetic solution. Both groups recorded postoperative analgesia efficacy and need for opioids and compared in the first 8 hours after surgery.
Statistical analysis: Categorical data will be compared using the Chi-Square test. Continuous variables will be compared using a student t-test.A P-value of <0.05 will be considered statistically significant.
Results: The mean no. of fentanyl boluses given in Group 1 was 3.03±0.72 and in Group 2 was 1.66±0.66 which is statistically significant (P<0.05). The mean total consumption of fentanyl in mcg in Group 1 was 75.83±17.96 and in Group 2 was 41.66±16.52 which is statistically significant (P<0.05).
Conclusion: We conclude that adding an obturator nerve block to the femoral block results in a significant reduction in total requirements for opioids in the first 8 hrs after TKR.