Low-Volume Brachial Plexus Block Providing Surgical Anesthesia for Distal Arm Surgery Comparing Supraclavicular, Infraclavicular, and Axillary Approach: A Randomized Observer Blind Trial

Table 3

Block characteristics.

	AX	IC	SC	ANOVA	Tukey’s HSD or Fisher’s exact test
Performance time [seconds]^(1)	184 [86]	179 [83]	210 [57]		NS
Needle passes [n]^(2)	6.0 [3.0]	4.0 [2.3]	6.0 [4.0]		AX > IC, ; SC > IC,
Injections [n]^(3)	9.0 [3.3]	6.0 [3.0]	9.0 [3.0]		AX > IC, ; SC > IC,
Overall visibility [good/medium/poor]^(4)	4/8/22	17/8/15	20/14/6	n/a	AX < IC, ; AX < SC,
Visibility of substructures [good/medium/poor]	Musc.cut. 28/3/3, median 20/13/1, ulnar 15/12/7, radial 6/12/16	Lateral cords 28/8/4, medial cords 21/10/9, posterior cords 27/6/7	n/a	n/a	n/a
Procedural pain [no pain/acceptable/painful]^(5)	20/18/2	20/16/4	25/12/3	n/a	NS

-values for the Anderson-Darling normality test results: (1) performance time: AX, ; SC, ; IC, ; (2) needle passes: AX, ; SC, ; IC, ; (3) aliquots: AX, , SC, ; IC, . Continuous variables are reported as median [interquartile range], and comparisons are analyzed by one-way ANOVA and subsequent Tukey HSD test. For categorical variables, comparisons are analyzed by two-tailed Fisher’s test. Additional Fisher’s tests: (4) visibility: IC = SC, ; (5) procedural pain: AX = IC, ; AX = SC, ; IC = SC, . AX, axillary; IC, infraclavicular; SC, supraclavicular; n, numbers; n/a, not applicable; NS, not significant ().