Send letter to journal:
Re: The reduction of shoulder dislocations requires appropriate analgesia

I read with interest Moharari et al study and their conclusion that intra-articular lidocaine produces the same pain relief as intravenous meperidine and diazepam and that is a suitable alternative to sedation-analgesia for closed reduction of anterior shoulder dislocation.

The authors achieved a very high rate of successful reduction with the traction counter-traction technique by two specifically trained operators. There were no failures in the 48 patients who had their dislocations reduced, 24 patients received 25 mg of meperidine and 5 mg of diazepam and 24 patients received 20 ml of 1% lidocaine intra-articularly.

The administered doses of analgesic in the study seem lower and that of sedative higher than those that most would normally use. The mean pain scores before reduction in both groups were 57.9 in the intravenous sedation-analgesia arm and 52.6 in the intra-articular lidocaine group, which is suggestive of insufficient analgesia in both groups and over sedation in the intravenous group, as 5 out of 24 patients had respiratory depression requiring bag mask ventilation.

Many would use more than one technique and most would administer the combination of a titrated dose of an intravenous opiate with a smaller dose of a short acting benzodiazepine such as Midazolam. Propofol with remifentanil 1 and etomidate alone 2 are recent additions to the multiple drug combinations available.

There must be very few situations in clinical practice where intra- articular lidocaine should be considered as first choice. Furthermore, the majority of those reducing dislocated shoulders do not have sufficient experience with its use, perhaps because it has failed to convince. Until more date is made available, intravenous sedation-analgesia in safe and effective doses should remain the first choice. Familiarity with a combination of techniques is an important advantage for successful reduction.

Emergency medicine physicians should become proficient with a number of techniques and medications in order to quickly and safely reduce shoulder dislocations.3

References

Send letter to journal:
Re: Re: Intra-articular lidocaine versus intravenous meperidine/diazepam in anterior shoulder dislocatio

We appreciate Dr Plutarco E Chiquito for his interest and comments about our recently published study of Intra-articular lidocaine versus intravenous meperidine/diazepam in anterior shoulder dislocation [1]. This letter is in response to his comments; however, it should be noted that not many studies are performed in this field, many of them have similar methods and limitations, suggesting that further studies are needed. Chiquito has indicated that the successful reduction rate in our study is surprisingly high, referring to his study (unpublished data) that has reported a lower success rate; it should be noted that our study was performed in a hospital with a high load of trauma patients admitted in the center each day, many of which suffer from shoulder dislocations. As a result, our team has a long experience in performing such procedures. Chiquito has also suggested in his letter that we have prescribed subtherapeutic doses of intravenous drugs (25 mg mepiridine, 5 mg diazepam) in our study, mentioning the high pain scores in the group receiving this type of sedation. The reason is obvious, the study was performed in the emergency department setting, where there are not enough personnel and monitoring devices to take care of the patients in case any complication develops. Five out of 24 patients receiving intravenous sedation developed respiratory depression in our study, suggesting that we should have been prepared for managing complicated cases if we had used higher doses. In other words, looking after a complicated case in such a setting would be not only costly and time consuming but also dangerous and life threatening, which suggests the very dose as an appropriate value for our emergency setting. In addition, previous similar studies had also used similar doses compared to the amount prescribed in our study: The doses prescribed in the study performed by Matthew et al was 10 mg morphine and 2 mg midazolam [2], and in the Miller et al’s study was 100 mcg fentanyl and 2 mg midazolam [3]. However, in view of the fact that fixed doses may lead to complications in certain patients such as elderly individuals with a low cardiac and respiratory reserve, and pregnant women, particularly in a setting which lacks necessary therapeutic drug monitoring devices, prescribing such drugs using weight based doses rather than the fixed ones would be more appropriate. But none of the previous studies performed in this field nor our study has used such a system. Chiquito has also suggested that Etomidate alone is a safe and effective agent in patients looking forward for the procedure [4]. It should be noted that despite the fact that the very drug is commonly used for short- term orthopedic procedures, Etomidate does not have any analgesic properties. Chiquito has also recommended that asking the patients upon their pain during the procedure is a more accurate manner compared to the data gathered after the procedure similar to what was performed in our study. His hypothesis is completely true, however, not feasible; traction-counter traction is a uncomfortable procedure; as a result it is hard to receive an appropriate answer from the patient during the procedure. In closing, it should be noted that all the available data [2, 3, 5-10] indicate the method as an effective alternative in the emergency setting.

References 1. Moharari RS, Khademhosseini P, Espandar R, Asl Soleymani H, Talebian MT, Khashayar P, et al. Intra-articular lidocaine versus intravenous meperidine/diazepam in anterior shoulder dislocation: a randomised clinical trial. Emergency Medicine Journal 2008; 25: 262-4.

2. Matthews DE, Roberts T. Intraarticular lidocaine versus intravenous analgesic for reduction of acute anterior shoulder dislocations. A prospective randomized study. American Journal of Sports Medicine 1995;23:54-8.

3. Miller SL, Cleeman E, Auerbach J, Flatow EL. Comparison of intra- articular lidocaine and intravenous sedation for reduction of shoulder dislocations: a randomized prospective study. Journal of Bone and Joint Surgery (American) 2002; 84-A: 2135-9.

4. Burton JH, Bock AJ, Strout TD, et al. Etomidate and midazolam for reduction of anterior shoulder dislocation: a randomized controlled trial. Ann Emerg Med 2002; 40: 496-504.

5. Kosnik J, Shamsa F, Raphael E, Huang R, Malachias Z, Georgiadis GM. Anesthetic methods for reduction of acute shoulder dislocations: a prospective randomized study comparing intraarticular lidocaine with intravenous analgesia and sedation. American Journal of Emergency Medicine 1999;17:566-70.

6. Orlinsky M, Shon S, Chiang C, Chan L, Carter P. Comparative study of intra-articular lidocaine and intravenous meperidine/diazepam for shoulder dislocations. Journal of Emergency Medicine 2002;22:241- 5.

7. Paudel K, Pradhan RL, Rijal KP. Reduction of acute anterior shoulder dislocations under local anaesthesia - a prospective study. Kathmandu University Medical Journal 2004;2:13-7.

8. Pradhan RL, Lakhey S, Pandey BK, Rijal KP. Reduction of acute anterior shoulder dislocations: comparing intra- articular lignocaine with intravenous analgesia. Journal of the Nepal Medical Association 2006; 45: 223- 7.

9. Suder PA, Mikkelsen JB, Hougaard K, Jensen PE. Reduction of traumatic secondary dislocations with lidocaine. Archives of Orthopaedic and Trauma Surgery 1995; 114: 233-6.

Send letter to journal:
Re: Intra-articular lidocaine versus intravenous meperidine/diazepam in anterior shoulder dislocation

I read with interest Moharari et al study and their conclusion that intra-articular lidocaine before closed reduction of anterior shoulder dislocation produces the same pain relief as intravenous meperidine and diazepam, as measured on a 100 mm analogue visual scale and that lidocaine is a suitable alternative to sedation-analgesia.

Pain worsens muscle spasm and compromises reduction, as well as being unacceptable to the patient. The authors achieved a very high rate of successful reduction, as all the 48 patients had their dislocations reduced, 24 patients received 25 mg of meperidine and 5 mg of diazepam and 24 patients received 20 ml of 1% lidocaine intra-articularly. A prospective, non randomized study of 50 consecutive patients with anterior dislocation (unpublished data), who were given 20 ml of 1% of intra-articular lidocaine by A&E doctors showed that not all the dislocations could be reduced with the traction and counteraction technique, as a combination of manoeuvres was often required and that lidocaine did not provide adequate analgesia in all the patients, as many had to be given intravenous sedation-analgesia subsequently.

It would be important to highlight that Moharari's study reported mean pain scores after the injections and before reduction of 57.9 in the intravenous sedation-analgesia arm and 52.6 in the intra-articular lidocaine group, which suggests inadequate analgesia possibly due to sub- therapeutic dosage and that a high number of patients (5 out of 24) in the sedation-analgesia group had respiratory depression requiring bag mask ventilation, which suggests over sedation.

A higher dose of opiate combined with a short acting benzodiazepine in smaller doses is favoured by many, as it provides adequate pain relief without unwanted complications or prolonged hospital stay. Intravenous propofol with remifentanil 1 and etomidate alone 2 have also been found to be safe, and effective.

It would be important to add that pain scoring during manipulation was not reported in the lidocaine group; pain scores after the administration of sedation/analgesia may had been inaccurate because of euphoria, drowsiness or amnesia caused by the medication given and that criteria for hospital discharge was not detailed in the study.

There are very few situations in clinical practice where intra- articular lidocaine may be selected and until more data is available, sedation-analgesia should remain the first choice followed by a general anaesthetic if this fails. Emergency medicine physicians should become experts with a number of techniques in order to quickly and safely reduce shoulder dislocations.3

References