Comparison of an upper limb nerve block using local anaesthetic with opioid analgesia for pain relief following major shoulder surgery

Pain following surgical procedures can sometimes increase the incidence of complications in the body. It is important to manage this pain effectively. Major shoulder surgery can cause severe pain. Effectively treating this pain will help reduce complications and will promote early mobilization. A wide range of methods are used to treat pain after major shoulder surgery, including administration of opioid (derived from opium) and non-opioid pain killers and administration of drugs that produce numbness and hence pain relief in and around the shoulder joint or around the nerves supplying the upper limb. We compared the usefulness of a continuous upper limb nerve block performed by injecting local anaesthetic into the neck close to where the nerves originate (interscalene brachial plexus block—ISBPB group) with the administration of opioid pain killers into a vein, into a muscle or under the skin (any route other than by mouth)—the parenteral opioid group.

Evidence obtained is current to December 2012. We included two studies involving 147 participants. Seventeen participants were excluded (16 from the ISBPB group and one from the other), leaving 130 participants: 66 in the ISBPB group and 64 in the parenteral opioid group. The studies were of medium to low quality because of issues with study design, and one of the trials was sponsored by a drug company.

The severity of pain was assessed by the patient using a numerical scale on which zero was considered as no pain and 10 or 100 as the worst imaginable pain for 72 hours in one study and 48 hours in the other. The severity of postoperative pain was significantly less for the ISBPB group at all time points in one study and at all but one time point in the other study.

No concrete conclusions can be drawn because of the small number of studies, which were not of high quality. However, from the available evidence, it can be seen that in one of the trials, the requirement for additional painkiller (piritramide) was significantly higher in the parenteral opioid group, whereas the other trial did not mention this. The incidence of nausea and vomiting was significantly less in the ISBPB group when compared with the parenteral opioid group. Complications related to ISBPB were virtually eliminated when ultrasound was used to perform ISBPB.

Authors' conclusions: 

Because of the small number of studies (two) relevant to the subject and the high risk of bias of the selected studies, no reasonable conclusion can be drawn.

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Background: 

Postoperative pain may lead to adverse effects on the body, which might result in an increase in morbidity. Its management therefore poses a unique challenge for the clinician. Major shoulder surgery is associated with severe postoperative pain, and different modalities are available to manage such pain, including opioid and non-opioid analgesics, local anaesthetics infiltrated into and around the shoulder joint and regional anaesthesia. All of these techniques, alone or in combination, have been used to treat the postoperative pain of major shoulder surgery but with varying success.

Objectives: 

The objective of this review was to compare the analgesic efficacy of continuous interscalene brachial plexus block (ISBPB) with parenteral opioid analgesia for pain relief after major shoulder surgery.

Search strategy: 

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (2012, Issue 12), MEDLINE (1950 to December 2012), EMBASE (1980 to December 2012), Web of Science (1954 to December 2012), CINAHL (1982 to December 2012) and bibliographies of published studies.

Selection criteria: 

We included randomized controlled trials assessing the effectiveness of continuous ISBPB compared with different forms of parenteral opioid analgesia in relieving pain in adult participants undergoing elective major shoulder surgery.

Data collection and analysis: 

Two review authors independently assessed trial quality and extracted outcome data.

Main results: 

We included two randomized controlled trials (147 participants). A total of 17 participants were excluded from one trial because of complications related to continuous ISBPB (16) or parenteral opioid analgesia (one). Thus we have information on 130 participants (66 in the continuous ISBPB group and 64 in the parenteral opioid group). The studies were clinically heterogeneous. No meta-analysis was undertaken. However, results of the two included studies showed better pain relief with continuous ISBPB following major shoulder surgery and a lower incidence of complications when interscalene block is performed under ultrasound guidance rather than without it.