63 Intravascular Injections
Ultrasound guidance for regional blocks appears to reduce but not eliminate the vascular puncture risk. This is similar to what has been reported for ultrasound guidance for other interventions.1
Small-volume test injections (0.5-1 mL) are useful for detecting intravascular injections.2 If the injection is not visualized, it should be stopped immediately. It is best to presume intravascular injection or some other adverse event.
Despite this favorable safety profile, intravascular injection with systemic toxicity has been reported with ultrasound guidance.3,4 Another concern is that probe compression may prevent detection of intravenous injection by collapsing the vein after puncture.5