Lidocaine-Midazolam-Fentanyl Combination in Controlling Pain for Reduction of Anterior Shoulder Dislocation; a Randomized Clinical Trial.

Introduction: Finding a fast-acting compound with minimal side-effects to induce a safe and efficient analgesia with short or medium duration of action is of great interest in the emergency department. The present study has been designed with the aim of comparing the effect of midazolam + fentanyl + lidocaine combination with midazolam + fentanyl + placebo in pain management of anterior shoulder dislocation reduction.

Methods: The present two-arm parallel double-blind randomized controlled trial was performed on patients who presented to emergency department with anterior shoulder dislocation. Patients were randomly allocated to the 2 treatment groups of midazolam + fentanyl + placebo (double-drug group) and midazolam + fentanyl + intravenous (IV) lidocaine (triple-drug group). Then outcomes such as treatment success rate and side-effects following prescription of drugs were compared between the 2 groups.

Results: 100 patients were included in the present study (50 patients in each group; mean age of the studied patients 27.3±8.9 years; 93.0% male). Using the double-drug regimen led to 35 (70%) cases of complete analgesia, while this rate in the triple-drug group was 41 (82%) cases (p=0.16). The calculated number needed to treat was 9 cases. This means that about one in every 9 patients in treatment arm will benefit from the treatment. The most important side-effects observed included dysrhythmia (1 patient in double drug and 1 patient in triple-drug group), apnea (2 patients in each group) and SPO2<90% (2 patients in triple-drug group) (p=0.78). Number needed to harm was 25 cases. In other words, for each 25 patients treated with the triple drug regimen, 1 case of SPO2<90% is observed.

Conclusion: Findings of the present study showed that adding IV lidocaine to IV midazolam + fentanyl drug combination does not provide additional analgesia in sedation for anterior shoulder reduction.