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Background and Aims We compared the superiority of two infraclavicular approaches, costoclavicular (CC) and lateral sagittal (LS), especially their sensorimotor effects and hemidiaphragmatic paralysis rates.

Methods Informed consent was obtained from 91 patients aged 18-80 years, ASA I-III, undergoing elective forearm and hand surgery. They were randomly assigned to 2 groups. Diaphragmatic movements were measured by USG in M-mode during deep and normal breathing. For both approaches, 30 mL of bupivacaine was injected with USG and nerve stimulator. Musculocutaneous, median, ulnar and radial nerve sensorimotor losses were checked every 5 minutes for 30 minutes. Diaphragmatic excursion was measured again 30 minutes after the block. The tourniquet area was checked and painless patients were not infiltrated, whereas others were infiltrated.

Results The onset time of sensory and motor block of the musculocutaneous and median nerves, motor block of the radial nerve and sensory block of the ulnar nerve and the number of patients with complete block at the end of 30 minutes were not different in either groups. During normal breathing, partial paralysis was observed in 10 CC and 11 LS patients, no complete paralysis. During deep breathing, partial paralysis was observed in 6 CC and 5 LS patients, no complete paralysis. Diaphragm excursion differences measured at baseline and 30 minutes after block were not significantly different in either group. Tourniquet infiltration was required significantly less in the CC than LS group.

Conclusions In conclusion, we think that both approaches can be used safely especially in patients with respiratory system diseases, but more studies are needed.