EFFICACY OF ULTRASOUND-GUIDED OBLIQUE SUBCOSTAL TRANSVERSUS ABDOMINIS PLANE BLOCK (OSTAP BLOCK) WITH ROPIVACAINE FOR POSTOPERATIVE ANALGESIA IN LAPAROSCOPIC CHOLECYSTECTOMY – A PROSPECTIVE OBSERVATIONAL STUDY. J Popl Ther Clin Pharmacol. 2024;31(9):623-631. doi:10.53555/3nemb660