Continuous Interscalene Block Results in Superior Recovery Throughout the First Postoperative Week

Continuous Interscalene Block in Patients Having Outpatient Rotator Cuff Repair Surgery: a Prospective Randomized Trial

The investigators undertook this prospective, randomized trial to compare the recovery profile throughout the first postoperative week in patients receiving continuous (CISB) interscalene brachial plexus block, single injection (SISB), or general anesthesia (GA) for arthroscopic rotator cuff repair surgery. Specifically, the effects of the three anesthetic techniques when used intraoperatively as a sole anesthesia modality were studied on postoperative pain, time-to-first pain, analgesic consumption, fast-tracked PACU bypass rate, length of PACU stay, time-to-discharge home, sleep duration, and related adverse effects. The investigators hypothesized that CISB results in a superior postoperative recovery profile as compared to SISB or GA alone.

Background The advantages of single injection (SISB) and continuous interscalene brachial plexus block (CISB) over general anesthesia (GA) only have been previously reported. However, few studies extended their observations beyond 48 postoperative hours, and no study has compared the effects of SISB and CISB as sole anesthesia modalities with GA only. We undertook this randomized trial to compare the recovery profile of patients receiving SISB, CISB or GA for arthroscopic rotator cuff repair surgery through the first postoperative week. Our primary hypothesis was that highest NRS pain rating (worst pain score) at the end of the study week is lower for patients in the CISB group than for patients in the SISB or GA groups. Methods After Institutional Review Board approval and informed consents were obtained, 71 patients of American Society of Anesthesiologists (ASA) physical status I-III, ≥18 years of age, and BMI≤35 kg/m2, scheduled for elective outpatient arthroscopic rotator cuff repair, were enrolled. CISB patients received 20 mL of 0.5% ropivacaine as bolus through the catheter whereas SISB patients received the same volume of injection through a needle. CISB patients received an infusion of 0.2% ropivacaine at 5mL/h with a patient controlled bolus of 5 mL hourly. GA only patients received a standardized general anesthetic. All patients were prescribed acetaminophen (500mg) with hydrocodone (7.5mg) every 4h as needed. CISB was discontinued 48 h after surgery. Postoperative highest pain scores (NRS) through the first postoperative week, time-to-first pain, analgesic consumption, fast-tracked postoperative care unit (PACU) bypass rate, length of PACU stay, time-to-discharge home, sleep duration, and related adverse effects were recorded in the PACU and at home on postoperative days 1, 2, 3, and 7.

Single injection interscalene brachial plexus block, Continuous interscalene brachial plexus block, General anesthesia, Postoperative pain, Recovery profile

In SISB group; a 5 cm block needle (Stimuplex®A, B Braun Medical, Bethlehem, PA) was inserted in-plane in order to place the needle tip between the upper and middle trunks of the brachial plexus (C5-C6). 20 mL 0.5% ropivacaine was injected through the needle. For CISB, a 5cm stimulating needle (Contiplex® Tuohy, B. Braun Medical, Bethlehem, PA) was inserted in-plane in order to place the needle tip between the upper and middle trunks of the brachial plexus (C5-C6). A nonstimulating catheter was inserted approximately 3 cm beyond the tip of the needle. 20 mL 0.5% ropivacaine was injected through the catheter.

The effects of the three anesthetic techniques (continuous interscalene brachial plexus block (CISB), single interscalene brachial plexus block (SISB), or general anesthesia (GA)) when used intraoperatively as a sole anesthesia modality were studied on postoperative pain (highest NRS pain rating)

The effects of the three anesthetic techniques (SISB, CISB, and GA) when used intraoperatively as a sole anesthesia modality were studied on postoperative pain (time-to-first pain).

The effects of the three anesthetic techniques (SISB, CISB, and GA) when used intraoperatively as a sole anesthesia modality were studied on postoperative pain (analgesic consumption).

To compare the recovery profile of patients receiving CISB, SISB, or GA for arthroscopic rotator cuff repair surgery throughout the first postoperative week by using fast-tracked PACU bypass rate

throughout the first postoperative week (how many patients left PACU immediately just after the operation)

To compare the recovery profile of patients receiving CISB, SISB, or GA for arthroscopic rotator cuff repair surgery throughout the first postoperative week by using length of PACU stay.

To compare the recovery profile of patients receiving CISB, SISB, or GA for arthroscopic rotator cuff repair surgery throughout the first postoperative week by using time-to-discharge home.

throughout the first postoperative week (how long patients stayed in the hospital (includes PACU and hospital time)

To compare the recovery profile of patients receiving CISB, SISB, or GA for arthroscopic rotator cuff repair surgery throughout the first postoperative week by using sleep duration.

Inclusion Criteria: American Society of Anesthesiologists (ASA) physical status I-III patients ≥ 18 years of age BMI ≤ 35 kg/m2 Scheduled for elective arthroscopic shoulder surgery Exclusion Criteria: Patients who were undertaken open shoulder procedures Patients with difficulty understanding the instructions for using the anesthetic infusion pump and/or pain scales Patients with contraindications to regional anesthesia (e.g., allergy to a local anesthetic (LA), local infection, coagulopathy) Patients with significant neurologic disorders of the upper extremity, psychiatric or cognitive disorders, history of substance abuse or chronic opioid use

Salviz EA, Xu D, Frulla A, Kwofie K, Shastri U, Chen J, Shariat AN, Littwin S, Lin E, Choi J, Hobeika P, Hadzic A. Continuous interscalene block in patients having outpatient rotator cuff repair surgery: a prospective randomized trial. Anesth Analg. 2013 Dec;117(6):1485-92. doi: 10.1213/01.ane.0000436607.40643.0a.