Programmed Intermittent Bolus During Continuous Interscalene Nerve Block for Shoulder Arthroplasty

Programmed Intermittent Bolus for Infusion of Local Anesthetic During Continuous Interscalene Nerve Blockade for Total Shoulder Arthroplasty: a Randomized Controlled Trial

A new infusion strategy named the 'programmed intermittent bolus' (PIB) technique delivers the hourly dose within minutes compared to the traditional infusion that delivers such dose over an hour. The PIB technique has demonstrated superior patient satisfaction and reduced local anesthetic consumption when utilized for pain control during labour and delivery. However, it is not known if the PIB technique gives any benefits during a continuous nerve block in other settings. The aim of this randomized controlled trial (RCT) is to elucidate if PIB is better than (traditional) continuous infusion for postoperative analgesia in patients receiving a continuous nerve block for total shoulder arthroplasty with respect to pain control.

Local anesthetics are often given in a continuous fashion to block specific nerves after an operation for pain control. A new infusion strategy named the 'programmed intermittent bolus' (PIB) technique delivers the hourly dose within minutes compared to the traditional infusion that delivers such dose over an hour. The PIB technique has demonstrated superior patient satisfaction and reduced local anesthetic consumption when utilized for pain control during labour and delivery. However, it is not known if the PIB technique gives any benefits during a continuous nerve block in other settings. The aim of this randomized controlled trial (RCT) is to elucidate if PIB is better than (traditional) continuous infusion for postoperative analgesia in patients receiving a continuous nerve block for total shoulder arthroplasty with respect to pain control.

For the experimental group, patients will receive 5 mL of the study solution as a bolus every hour via a PIB-capable infusion pump.

The control (standard care) group will receive the study solution at a rate of 5mL/h continuously via the current infusion pump.

The Smith CADD(R)-Solis Ambulatory Infusion Pump will be used to provide programmed intermittent bolus for the interscalene block.

The Smith CADD(R)-Solis Ambulatory Infusion Pump will be used to provide continuous infusion for the interscalene block.

Inclusion Criteria: Adult patients American Society of Anesthesiologists (ASA) Physical Status I to III Exclusion Criteria: Body mass index (BMI) > 40 Not able to communicate in ENglish Unable to obtain consent Infection over site of placement Severe respiratory disease Cognitive or psychiatric history that would make it difficult to assess pain score Complex regional pain syndrome Chronic pain condition such as fibromyalgia, neuropathic pain Preoperative opioid use greater than the equivalent of morphine 50 mg PO daily Allergy to any of the study drug Coagulopathy

Chong MA, Wang Y, Dhir S, Lin C. Programmed intermittent peripheral nerve local anesthetic bolus compared with continuous infusions for postoperative analgesia: A systematic review and meta-analysis. J Clin Anesth. 2017 Nov;42:69-76. doi: 10.1016/j.jclinane.2017.08.018. Epub 2017 Aug 19.