Ultrasonographic Guidance Improves Sensory Block and Onset Time of Three-in-One Blocks

The Sensitivity of Motor Response to Nerve Stimulation and Paresthesia for Nerve Localization As Evaluated by Ultrasound

“…Also, some early data from small prospective randomized trials suggest a higher success rate of nerve block when ultrasonographic guidance is used, which would support a higher precision of nerve localization. 7,8 In addition, in the present study, 97% of patients developed complete sensory block in the territory of the target nerve within 30 minutes. In our opinion, this high rate of complete sensory block supports the selection of real-time ultrasound guidance as a reference test.…”

Femoral nerve blocks in fractures of femur: variation in the current UK practice and a review of the literature

“…In this study, femoral artery puncture was observed in two cases in each of the two NS study groups 37. In both these studies, Marhofer et al did not provide a power calculation, and did not describe the method of randomisation 36 37. So, these RCTs raise the possibility of bias or error in methodology.…”

“…Also, there was no statistically significant difference between the ultrasound and NS groups in the incidence of paraesthesia during the block placement or persistent neurological symptoms after the block resolution 40. ultrasound-guided technique is of use especially in patients in whom the anatomical landmarks are difficult to identify, such as in morbid obesity, previous surgery in the area or patients with anatomical anomalies 36. The NICE also supports the use of ultrasound for regional blocks 41…”

“…They concluded that ultrasound guidance reduced the block onset time and improved the quality of sensory block. Femoral artery puncture was observed in three cases, all in NS group 36. In 1998, Marhofer et al , in their RCT on 60 patients, again concluded that ultrasound reduced the block onset time and improved the quality of sensory block.…”

“…He also suggested that ultrasound-guided blocks might be performed using lower LA doses 39. The use of smaller doses of LA is especially useful while managing patients with cardiovascular compromise in whom the dose of LA should be kept to a minimum to prevent unwarranted cardiovascular side effects 36 37. In 2009, Abrahams et al , in their meta-analysis, concluded that blocks performed under ultrasound guidance had higher success rate, had faster onset time, lasted longer and had lower risk of vascular puncture (all clinically significant); also took less time to perform, but this result was clinically not significant.…”