Effects of Catheter Tip Location on the Spread of Sensory Block Caused by a Continuous Thoracic Paravertebral Block: A Prospective, Randomized, Controlled, Double-Blind Study

Figure 4

Number of dermatomes blocked at 2 and 24 h after surgery in patients receiving a continuous thoracic paravertebral block. A and P indicate group A and group P, respectively. The horizontal lines indicate the medians, the boxes indicate the interquartile ranges, and the whiskers indicate the ranges. The P-values were calculated using the Mann-Whitney U test.