Background and Aims Supraclavicular block (SCB) is associated with excellent post-operative patient outcomes for upper limb surgeries. Bupivacaine, a long-acting regional anaesthetic, efficacy of which is altered with the co-administration of additives.

Aim of the study was to assess the efficacy of supraclavicular block with 0.5% bupivacaine compared to co-administration of additives and the associated complications.

Methods Following ethical clearance and informed consent, over a period of 5 months from June 2020, 152 adult patients at Teaching Hospital Anuradhapura Sri Lanka, undergoing upper limb surgeries were divided into 4 groups & prospectively followed-up. All received 0.5% of Bupivacaine while additives 2% Lidocaine, 8.4% sodium bicarbonate & 8 mg Dexamethasone was added to other 3 groups. Sensory and Motor block onset time, duration of post-block analgesia, acute and late complications and patient satisfaction was noted.Data was analysed using descriptive statistics & ANOVA, using SPSS V.25.

Results Successful surgical anesthesia was achieved in all with 0 cases of long-term neurological complications with 94% patient satisfaction. The motor & sensory block onset time & post block analgesia duration respectively for Lidocaine (9.74min,9.74 min & 7.07 h), Bicarbonate (12.89min, 16.32min & 12.09h),dexamethasone (19. 34 min, 17.24min & 20.87h) & Bupivacaine was (20.39min, 18.42min & 13.15h).

Conclusions The differences between bupivacaine and lidocaine groups for sensory & motor block onset times & between Bupivacaine & dexamethasone groups for post-block analgesia duration were statistically significant (p<.001).Supraclavicular block has minimal associated complications & additives Lidocaine shortens the onset of anaesthesia and the duration of analgesia while dexamethasone prolongs the duration of analgesia significantly.