Interest of Cryotherapy in Reducing Pain During Radial Arterial Blood Sampling

Arterial puncture for blood gas analysis is a diagnostic procedure used to assess arterial blood gases and monitor a patient's oxygenation status. It is widely regarded by nursing staff as one of the most painful routine procedures. Despite this, the use of local anesthesia prior to arterial puncture remains uncommon in clinical practice. Several types of anesthetic agents and administration techniques have been evaluated, with mixed results regarding their effectiveness in reducing patient-reported pain. Studies comparing subcutaneous lidocaine injection or ethyl chloride spray to no analgesic intervention have shown that ethyl chloride does not significantly reduce pain. Moreover, the discomfort caused by lidocaine injection appears to be comparable to that of the arterial puncture itself, suggesting limited overall benefit from this approach. Other investigations have similarly reported a lack of significant pain reduction with ethyl chloride spray, although some contradictory findings exist. Ultrasound-guided arterial puncture has been shown to improve success rates and shorten procedure duration; however, it does not appear to influence pain perception. The impact of needle size on pain intensity has also been explored, with conflicting results. Some studies found no significant difference in pain when using different gauge needles, while others reported reduced pain with the use of finer needles, such as insulin needles, compared to standard arterial puncture needles. Topical anesthetic creams combining lidocaine and prilocaine have been assessed in randomized, double-blind trials. These studies found no significant difference between anesthetic and placebo groups in terms of pain intensity or the proportion of painful procedures. More recently, cryotherapy has been investigated as a non-pharmacological method to reduce pain prior to arterial puncture. Several randomized controlled trials using varying cryotherapy protocols have generally reported a signi