Gut Microbiota and Pulmonary Complications After Non Cardiac Elective Surgery in Elderly Patients

This study adopts a combination of retrospective and prospective cohort research methods to explore the composition of preoperative oropharyngeal and gut microbiota in elderly patients undergoing elective upper abdominal surgery, aiming to analyze the correlation between preoperative oropharyngeal and intestinal microbiota composition and metabolite levels and the occurrence of postoperative pulmonary complications (PPCs). The research subjects of the retrospective cohort study were participants (ClinicalTrials.gov No. NCT05679661) included in the prospective RCT on the effects of perioperative immune nutrition intervention and oral hygiene on postoperative complications in elderly patients, which was conducted at Peking Union Medical College Hospital from January 2023 to present. The prospective cohort study plans to continue enrolling elderly patients aged ≥ 65 who underwent elective upper abdominal surgery.

This study collects preoperative oropharyngeal and fecal samples, as well as preoperative plasma from patients for microbial sequencing and untargeted metabolomics analysis. The main outcome measurement is PPCs, which include pneumonia, atelectasis, and hypoxemia within 7 days after surgery. Inflammatory cells and cytokines in peripheral blood are secondary outcomes.

Study Overview

• Status: Recruiting
• Conditions: Gut Microbiota; Postoperative Pulmonary Complications
• Intervention / Treatment: Procedure: Elective upper abdominal surgery

• Study Type: Observational
• Enrollment (Estimated): 100

Contacts and Locations

• Study Contact: Name: Qianmei Zhu; Phone Number: 18810651253; Email: zhuqm661@163.com

Study Locations

• China
  • Beijing
    • Beijing, Beijing, China, 100730
      • Recruiting
      • Department of Anesthesiology, Peking Union Medical College Hospital
      • Contact: Qianmei Zhu; Phone Number: 18810651253; Email: zhuqm661@163.com

Participation Criteria

Eligibility Criteria

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

• Sampling Method: Probability Sample

Study Population

Elderly patients over 65 years old who plan to undergo elective upper abdominal surgery

Description

Inclusion Criteria:

1. Age: ≥ 65 years old;
2. Surgery: Upper abdominal surgery (expected duration ≥ 2 hours);
3. Anesthesia methods: general anesthesia, tracheal intubation;
4. ASA classification: I-IV levels;
5. Postoperative Pulmonary Complications Risk Score (ARISCAT): Medium to High Risk
6. Patients or their families are able to understand the research protocol and are willing to participate in this study, providing written informed consent

Exclusion Criteria:

1. Emergency surgery;
2. This is the second surgery within the past month;
3. Preoperative presence of pulmonary infection or other serious pulmonary complications
4. Patients who have used antibiotics, probiotics, and acid suppressants within one month before surgery

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
PPCs+ group; Patients who experienced postoperative pulmonary complications belong to the PPC positive group	Procedure: Elective upper abdominal surgery; The included elderly patients are those who are preparing for elective upper abdominal surgery and the surgery time exceeds 2 hours.
PPCs- group; Patients who experienced no postoperative pulmonary complications belong to the PPC negative group	Procedure: Elective upper abdominal surgery; The included elderly patients are those who are preparing for elective upper abdominal surgery and the surgery time exceeds 2 hours.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of participants with postoperative pulmonary complications	Including pneumonia, atelectasis, and hypoxemia	Within 7 days after surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of inflammatory cells in peripheral blood before and after surgery	Inflammatory cells include white blood cells, neutrophil count, and lymphocyte count	Before and within 7 days after surgery
Concentration of inflammatory cytokines in peripheral blood before and after surgery	Inflammatory factors include high-sensitivity C-reactive protein (CRP) and procalcitonin (PCT)	Before and within 7 days after surgery

Collaborators and Investigators

• Sponsor: Peking Union Medical College Hospital

Study record dates

Study Major Dates

• Study Start (Actual): February 1, 2023
• Primary Completion (Estimated): December 31, 2025
• Study Completion (Estimated): December 31, 2025

Study Registration Dates

• First Submitted: July 17, 2024
• First Submitted That Met QC Criteria: July 17, 2024
• First Posted (Actual): July 22, 2024

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: February 26, 2025
• Last Verified: February 1, 2025

More Information

Terms related to this study

• Other Study ID Numbers: K5484

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No