Less painful arterial blood gas sampling using jet injection of 2% lidocaine: a randomized controlled clinical trial

The aim of this study was to compare pain levels from arterial blood gas (ABG) sampling performed with or without application of lidocaine via jet injector.

Pain is still a primary concern in the emergency department. Arterial blood gas sampling is a very painful procedure. No better technique for decreasing the pain of the ABG procedure has been presented. An ideal local anesthesia procedure for ABG sampling should be rapid, easily learned, inexpensive, and free of needlestick risk.

We evaluated the effectiveness of a lidocaine jet injection technique in achieving satisfactory pain control in patients undergoing ABG sampling. Forty-two patients were randomized to 2 groups: group A, which received lidocaine by jet injection (0.2 mL of lidocaine 2%), and group B, a control group that received a topical application of 1 mL of lidocaine gel 2% 2 minutes before the ABG sampling. Pain was assessed on a 10-cm visual analog scale (0, absence of pain; 10, greatest imaginable pain).

The pain visual analog scale score during ABG sampling was considerably lower in group A compared with group B (1.29 ± 0.90 vs 4.19 ± 1.43; P < .001). The number of attempts required for ABG sampling was significantly lower in group A compared with group B (1.29 ± 0.46 vs 2.1 ± 0.12; P = .009). All residents reported ease of use with the lidocaine jet injection procedure (P < .05).

Lidocaine jet injection provides beneficial and rapid anesthesia, resulting in less pain and a greater rate of successful ABG sampling. Therefore, it is recommended for use before ABG sampling to decrease the patient's pain and the number of unsuccessful attempts and to enhance the patient's satisfaction.