Timing of Opioid Administration and Postoperative Respiratory Depression.

NCT07227389 | Not Yet Recruiting

• 1 other identifier: IRB-23-08-6045
• Study Type: observational
• Target: 52
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this study is to determine if a relationship can be detected between the administration of an opioid and quantitative respiratory depression in spontaneously breathing non-intubated patients who have undergone general anesthesia and have received perioperative opioids. The primary aim is to determine the temporal effect of opioid administration on respiratory depression as assessed by minute ventilation with a reduction of at least 20% in the percent of predicted minute ventilation. A secondary aim is to determine a dose response of opioid administration and its effect on minute ventilation. The investigators aim to determine the influence of opioid administration on minute ventilation on spontaneously breathing patients during post-anesthesia care unit (PACU) stay.

Conditions

Respiratory Complications; Opioid Induced Respiratory Depression; Postoperative Respiratory Complications

Keywords

opioids; bio-impedance; hypoxia; hypercapnia; minute ventilation

Outcome Measures

Primary Outcomes (4)

• Respiratory interventions 1

  Initiation or cessation of mechanical ventilation

  Within 4 hours of patient admittance to Post Anesthetic Care Unit (PACU)

• Respiratory interventions 2

  Initiation or cessation of Bilevel Positive Airway Pressure

  Within 4 hours of patient admittance to Post Anesthetic Care Unit

• Respiratory interventions 3

  Initiation/cessation of high flow nasal cannula

  Within 4 hours of patient admittance to Post Anesthetic Care Unit

• Respiratory interventions 4

  Initiation/cessation of low flow nasal cannula

  Within 4 hours of patient admittance to Post Anesthetic Care Unit

Secondary Outcomes (7)

• Oxygen saturation of peripheral blood (SpO2)

  Duration of PACU stay (up to 4 hours)

• Arterial Blood gas levels

  Duration of surgery (up to 2hrs)

• Venous Blood gas levels

  Duration of surgery (up to 2hrs)

• Hypercapnia

  Duration of patient stay in PACU (up to 4 hours)

• Hypoxia

  Duration of patient stay in PACU (up to 4 hours)

Study Arms (1)

Study group

Patients receiving general anesthesia with an expected anesthetic time of at least 2 hours

Diagnostic Test: Respiratory volume monitoring

Interventions

Respiratory volume monitoring DIAGNOSTIC_TEST

Noninvasive continuous respiratory monitoring utilizing bio-impedance to detect tidal volumes, respiratory rate, and minute ventilation.

Study group

Eligibility Criteria

• Age: 18 Years - 85 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Surgical patients receiving general anesthesia with an expected anesthetic time of at least 2 hours

You may qualify if:

• Written informed consent
• Adults ≥18 years of age and ≤85 years of age
• Patients planned for general anesthesia with an expected anesthetic time of at least 2 hours
• Patients expected to receive postoperative opioid analgesia

You may not qualify if:

• Non-operative procedure (imaging)
• Patients not admitted to the PACU postoperatively
• Use of patient-controlled analgesia systems
• Female patients who are pregnant or breastfeeding
• Patients with asymmetric lung disease
• American Society of Anesthesiologists (ASA) classification V
• Emergency surgery (ASA E Modifier)

Sponsors & Collaborators

• Wayne State University: lead

Study Sites (1)

Detroit Medical Center

Mount Clemens, Michigan, 48043, United States

Location

MeSH Terms

Conditions

Hypoxia; Hypercapnia

Condition Hierarchy (Ancestors)

Signs and Symptoms, Respiratory; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Officials

• Wael Saasouh, MD

  Wayne State University

  PRINCIPAL INVESTIGATOR

Central Study Contacts

George M McKelvey, PhD

CONTACT

3135986036; George.McKelvey@northstaranesthesia.com

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Target Duration: 1 Day
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Clinical Assistant Professor

Study Record Dates

• First Submitted: November 7, 2025
• First Posted: November 12, 2025
• Study Start: December 1, 2025
• Primary Completion (Estimated): December 1, 2028
• Study Completion (Estimated): January 1, 2029
• Last Updated: November 14, 2025

Record last verified: 2025-11

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)