Preoperative Maximum Inspiratory Pressure and Outcomes After Interscalene Block in Obese Patients

A Pilot Study on Inspiratory Dynamics and the Effect of Body Mass Index on Respiratory Outcomes After Temporary Hemi Diaphragmatic Paresis Related to Brachial Plexus Blocks

The study aims to explore if Maximum Inspiratory Pressure can predict postoperative breathlessness in obese patients receiving interscalene blocks for shoulder surgery.

The main question is: does baseline Maximum Inspiratory Pressure have any association with postoperative breathlessness after interscalene blocks in class 2 or higher obese patients (BMI>35).

Preoperative and postoperative lung volumes, pressures, breathlessness score and respiratory outcomes will be measured on participants already receiving shoulder surgery with interscalene blocks.

Study Overview

• Status: Completed
• Conditions: Dyspnea After Interscalene Nerve Block
• Intervention / Treatment: Diagnostic test: Maximum Inspiratory Pressure monitoring

• Study Type: Observational
• Enrollment (Actual): 45

Contacts and Locations

Study Locations

• United States
  • North Carolina
    • Chapel Hill, North Carolina, United States, 27599
      • University of North Carolina

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Probability Sample

Study Population

Adult patients presenting for shoulder surgery with preoperative interscalene block (Groups 1 and 2). Group 3 includes adult patients presenting for non thoracic, non abdominal surgery under general anesthesia.

Description

Inclusion Criteria Groups 1 and 2

• Adults >18 years of age receiving shoulder surgery with preoperative interscalene block and general anesthesia;
• Speak English;

Group 3

· Adults >18 years of age receiving cystoscopy or lower extremity procedures receiving general endotracheal anesthesia

Exclusion Criteria All Groups

• Less than 18 years of age;
• currently pregnant;
• currently incarcerated;
• those with significant neuromuscular disease, tracheo-bronchial structural abnormalities, severe respiratory or severe cardiovascular comorbidity;
• those undergoing intra-abdominal or intrathoracic surgeries due to the potential to independently effect breathing

Study Plan

How is the study designed?

Number of groups / cohorts

3

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Block, Non-obese; Non-obese, Body Mass Index (BMI)<30, receiving interscalene block and general anesthesia for shoulder surgery	Diagnostic test: Maximum Inspiratory Pressure monitoring; Lung volumes, pressures and breathlessness scores to be measured in pre and post operative phase of care on the same day; Other Names: Spirometry measurements, Modified Borg breathlessness questionnaire
Block, Obese; Class 2 or higher Obese, BMI>35, receiving interscalene block and general anesthesia for shoulder surgery	Diagnostic test: Maximum Inspiratory Pressure monitoring; Lung volumes, pressures and breathlessness scores to be measured in pre and post operative phase of care on the same day; Other Names: Spirometry measurements, Modified Borg breathlessness questionnaire
Control; control group, included non-shoulder surgery patients receiving general anesthesia only	Diagnostic test: Maximum Inspiratory Pressure monitoring; Lung volumes, pressures and breathlessness scores to be measured in pre and post operative phase of care on the same day; Other Names: Spirometry measurements, Modified Borg breathlessness questionnaire

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of Moderate to Severe Breathlessness	Score of 3 or above on Modified Borg Breathlessness Scale	Baseline (Arrival to pre-operative phase), Recovery (Immediately post-surgical, up to 3 hours)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Oxygen Saturation in post-anesthesia care unit	Measured by pulse oximetry	Recovery (Immediately post-surgical, up to 3 hours)
Post-anesthesia care unit length-of-stay	Total time spent in post-operative phase of care	Recovery (Immediately post-surgical, up to 3 hours)
Duration of Oxygen supplementation in post-anesthesia care unit	Total duration of oxygen supplementation in post-operative phase of care	Recovery (Immediately post-surgical, up to 3 hours)

Collaborators and Investigators

• Sponsor: University of North Carolina, Chapel Hill
• Investigators: Principal Investigator: Monika Nanda, University of North Carolina

Study record dates

Study Major Dates

• Study Start (Actual): July 1, 2023
• Primary Completion (Actual): November 28, 2023
• Study Completion (Actual): January 10, 2024

Study Registration Dates

• First Submitted: July 31, 2024
• First Submitted That Met QC Criteria: August 7, 2024
• First Posted (Actual): August 12, 2024

Study Record Updates

• Last Update Posted (Actual): August 12, 2024
• Last Update Submitted That Met QC Criteria: August 7, 2024
• Last Verified: July 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Respiration Disorders; Signs and Symptoms, Respiratory; Dyspnea
• Other Study ID Numbers: 23-0924

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No