Diaphragmatic Paralysis Comparison Between Local Anesthetic Volumen Doses After Interscalene Block (REDOLEV-2019)

Diaphragmatic Paralysis After Interscalene Brachial Plexus Block: A Randomized, Double-blinded, Unicenter and Controlled Clinical Trial to Reduce the Dose of Levobupivacaine 0,25% 20 ml to 10 ml Undergoing Arthroscopic Shoulder Surgery

Arthroscopic shoulder surgery involves dynamic and severe postoperative pain. Interscalene brachial plexus block (IBPB) provides adequate analgesia but the spread of local anaesthetics administered causes a phrenic nerve block which entrains a non-negligible incidence of Hemidiaphragmatic paralysis acute (HDPA). This is a comparative, prospective, Unicenter, double-blind, two-arm, randomized and controlled clinical trial. 48 patients will be included. This RCT would demonstrate a low volume dose IBPB decrease the HDPA after IBPB in patients undergoing SAS, by using spirometry and ultrasound and it will not provide inferior postoperative analgesia according to opioid requirements of postoperative PCA in comparison to standard volume dose used in current practice.

Arthroscopic shoulder surgery involves dynamic and severe postoperative pain. Interscalene brachial plexus block (IBPB) provides adequate analgesia but the spread of local anaesthetics administered causes a phrenic nerve block which entrains a non-negligible incidence of Hemidiaphragmatic paralysis acute (HDPA). The primary study objective is to determine the HDPA diagnosed by using diaphragmatic thickness index in Ultrasound (US) after Low Volume (10 mL) versus Standard Volume (20 mL) of Levobupivacaine 0,25% for IBPB. Secondary end-points are 1) HDPA diagnosed by using FVC and FEV1 in spirometry, 2) HDPA diagnosed by using diaphragmatic excursion in US, 3) postoperative pain regarding time to first analgesic consumption and 24-hour cumulative total consumption of Patient-controlled analgesia (PCA) pump of Morphine IV and (4) postoperative harms between two trial-arms. This study is a comparative, prospective, Unicenter, double-blind and two-arm RCT. 48 patients will be included. This RCT would demonstrate a low volume dose IBPB decrease the HDPA after IBPB in patients undergoing SAS, by using spirometry and ultrasound and it will not provide inferior postoperative analgesia according to opioid requirements of postoperative PCA in comparison to standard volume dose used in current practice.

Diaphragmatic Paralysis, Interscalene Brachial Plexus Block, Ultrasound, Postoperative pain, Arthroscopic shoulder surgery.

The REDOLEV study is a randomized, comparative, prospective, unicenter, double-blind, two-arm and controlled Clinical trial (RCT).

After randomization, only Interscalene Block performer staff will know which intervention group is assigned to the participants. Spirometry and ultrasound assessments will be conducted by only one blinded anesthesiologist of Assessment staff who will not be communicated to IBPB staff. Recruitment and Assessment staff and participants will not be allowed to receive any information about the group allocation. Study unblinding will occur when every ultrasound and Spirometry assessments have been completed after 24-hour follow-up postoperative closeout. After follow-up finished, every study data will figure in the patient medical record. Code breaks should occur only in exceptional circumstances when knowledge of the actual treatment is absolutely essential for further management of the patient as an allergy episode. The Research staff will be encouraged to maintain the blind as far as possible. Unblinded IBPB staff will manage the emergency.

24 patients will be included in the Standard Volume Dose arm. 20 ml Levobupivacaine Hydrochloride 2.5 MG/ML will be administered in the Interscalene brachial plexus block before the arthroscopic shoulder surgery.

24 patients will be included in the Low Volume Dose arm. 10 ml Levobupivacaine Hydrochloride 2.5 MG/ML will be administered in the Interscalene brachial plexus block before the arthroscopic shoulder surgery.

Interscalene brachial plexus block is a locorregional anaesthesia technique which is indicated in shoulder and upper arm surgery. The goal of this block is to place the needle in the tissue space between the anterior and middle scalene muscles and inject local anesthetic until the spread around the brachial plexus is documented by ultrasound.

Levobupivacaine Hydrochloride 2.5 MG/ML is an anesthestic product intended for epidural, intradural and perineural administration. Levobupivacaine is chemically described as (S)-l-butyl-2-piperidylformo-2',6'-xylidide hydrochloride. It is a white crystalline powder with a molecular formula of C18H28N2O. HCl, with a molecular weight 324.9. FDA approval: NDA-20997 (1999).

The primary outcome is the difference in the proportion of patients with Hemidiaphragmatic paralysis acute (HDPA) according to diaphragmatic thickness ratio (DTR) in ultrasounds between the Treatment and Control groups. DTR will be the result of Inspiratory Diaphragmatic Thickness and Expiratory Diaphragmatic Thickness. The ratio will be defined by DTR=IDT/EDT. HDPA after IBPB at 4 hours will be diagnosed with a DTR<1.2.

This secondary outcome is the difference in the proportion of patients with Hemidiaphragmatic paralysis acute (HDPA) according to Forced Vital Capacity (FVC) in spirometry. HDPA will be diagnosed with a CVF diminution of >20%.

This secondary outcome is the difference in the proportion of patients with Hemidiaphragmatic paralysis acute (HDPA) according to forced expiratory volume in one second (FEV1) in spirometry. HDPA will be diagnosed with a FEV1 diminution of >20%.

This secondary outcome is the difference in the proportion of patients with Hemidiaphragmatic paralysis acute (HDPA) according to Diaphragmatic excursion expressed as number of intercostal spaces and motion type. HDPA will be diagnosed with a reduction of >25% number of intercostal spaces or a paradoxal or nule diaphragmatic motion.

This secondary outcome is the postoperative 24-hour cumulative IV morphine consumption (mg) of Patient controlled analgesia (PCA) pump.

This secondary outcome is the time to first analgesic consumption (minutes) of Patient controlled analgesia (PCA) pump.

This secondary outcome is the incidence, frequency and severity of Serious Adverse Events (SAE) as assessed by CTCAE v4.0 in the two study groups

Inclusion Criteria: Patients aged 18 to 80 years. ASA I-III. Scheduled for shoulder arthroscopic shoulder surgery and interscalene brachial plexus block. Exclusion Criteria: Age <18 and >80 years. Pregnancy. Exclusión to perform IBPB or spirometry. Allergy to amide group local anaesthetics, opioids or nonsteroidal anti-inflammatory drugs. Background of Pulmonary diseases (chronic obstructive pulmonary disease (COPD) and moderate, severe or not well-controlled asthma), diaphragmatic paralysis or neurological disease with diaphragmatic dysfunction, brachial plexus neuropathy or chronic opioid consumption (more than 3-months consumption or more than oral Morphine 1 mg 1-month). Coagulation disorders (INR>3, TTPA > 35 y AP <50%).

All collected IPD will be available on file in storage and on the Internet (URL undecided yet) after finishing the data collection for 25 years at the participating site.

To contact to Study Principal Investigator. To provide to Study Principal Investigator a request to explain the reason to access to IPD study.

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