Comparison of laparoscopy-guided with ultrasound-guided subcostal transversus abdominis plane block in laparoscopic cholecystectomy – A prospective, randomised study

BACKGROUND AND AIMS: Subcostal transversus abdominis plane (TAP) block is usually done under ultrasound guidance in laparoscopic cholecystectomy. Laparoscopic-guided subcostal TAP block is an alternate technique where ultrasound is not available. Our primary objective was to compare the success rate of ultrasound and laparoscopic approaches to the subcostal TAP block. The secondary objectives were to assess the duration of postoperative analgesia and morphine consumption postoperatively for 24 h. METHODS: Eighty patients undergoing laparoscopic cholecystectomy were randomly divided into two groups with patients receiving ultrasound-guided (group U) or laparoscopy-guided (group L) subcostal TAP block at the end of surgery. The success rate was assessed by a sensory blockade of T7 and T8 dermatomes 30 min after extubation. The duration of analgesia was taken as time from block administration to the visual analogue scale of ≥3. Morphine was administered in patient-controlled analgesia (PCA) pump with a bolus of 1 mg and a lock-out interval of 10 min. The total morphine consumption was recorded. The statistical analysis was performed with student t-test and Chi-square test. RESULTS: The success rate of group U (100%) was higher than group L (88%) but it was not statistically significant (P = 0.054). The duration of postoperative analgesia was significantly prolonged in group U (867.24 ± 135.83 min) than group L (751.31 ± 311.22 min) (P = 0.033). Morphine consumption was also less in group U (4.72 ± 0.94 mg) than group L (5.57 ± 2.53 mg) (P = 0.049). There was no significant difference in the VAS scores after 4 h postoperatively. CONCLUSION: Laparoscopy-guided subcostal TAP block is a suitable alternative to ultrasound-guided block and can be utilised in places where an ultrasound machine is not available.