Impact of Gut Microbiota and Tryptophan Metabolites on Acute Pain in Lumbar Disc Herniation Surgery Patients

NCT06502223 | Completed

• 1 other identifier: DEU-Çelik001
• Study Type: observational
• Target: 37
• Locations: 1 country
• Sites: 1

Brief Summary

It is well-established that the gut microbiota plays a crucial role in various pain mechanisms, including visceral pain, inflammatory pain, headache, neuropathic pain, and opioid tolerance. Changes in the gut microbiome can alter pain perception. In our study, The investigator investigated the effects of microbiota alterations and the associated tryptophan metabolites on acute pain using the Visual Analog Scale (VAS).

Conditions

Microbial Substitution; Tryptophan Metabolism Alterations; Postoperative Pain, Acute

Keywords

Microbiota; Tryptophan; Picolinic Acid; Kynurenic Acid; Xanthurenic Acid; Quinolinic Acid; Acute Pain

Outcome Measures

Primary Outcomes (8)

• Tryptophan metabolites (Picolinic Acid)

  2 mL of blood was used from the blood samples taken during routine surgery preparation for the patients and from the routine blood samples taken in the postoperative period, and no additional invasive intervention was performed. The investigator elucidated the relationship between picolinic acid and its variations due to microbiota alterations with VAS in acute pain. Preoperative, postoperative, 8th-hour, and 24th-hour blood samples were routinely collected from patients, with 2 mL of sample material used each time. After the necessary centrifugation processes, the relevant laboratory team analyzed the picolinic acid levels (ng/mL).

  Preoperative: Before surgery; Postoperative 8th-hour: 8 hours after surgery;Postoperative 24th-hour: 24 hours after surgery

• Tryptophan metabolites (3-Hydroxykynurenine)

  2 mL of blood was used from the blood samples taken during routine surgery preparation for the patients and from the routine blood samples taken in the postoperative period, and no additional invasive intervention was performed. The investigator elucidated the relationship between 3-Hydroxykynurenine and its variations due to microbiota alterations with VAS in acute pain. Preoperative, postoperative 8th-hour, and 24th-hour blood samples were routinely collected from patients, with 2 mL of sample material used each time. After the necessary centrifugation processes, the relevant laboratory team analyzed the 3-Hydroxykynurenine levels(ng/mL).

  Preoperative: Before surgery; Postoperative 8th-hour: 8 hours after surgery;Postoperative 24th-hour: 24 hours after surgery

• Tryptophan metabolites (Anthranilic Acid)

  2 mL of blood was used from the blood samples taken during routine surgery preparation for the patients and from the routine blood samples taken in the postoperative period, and no additional invasive intervention was performed. The investigator elucidated the relationship between anthranilic acid and its variations due to microbiota alterations with VAS in acute pain. Preoperative, postoperative, 8th-hour, and 24th-hour blood samples were routinely collected from patients, with 2 mL of sample material used each time. The relevant laboratory team measured the anthranilic acid levels (ng/mL) following the required centrifugation procedures.

  Preoperative: Before surgery; Postoperative 8th-hour: 8 hours after surgery;Postoperative 24th-hour: 24 hours after surgery

• Tryptophan metabolites (Kynurenine)

  2 mL of blood was used from the blood samples taken during routine surgery preparation for the patients and from the routine blood samples taken in the postoperative period, and no additional invasive intervention was performed. The investigator elucidated the relationship between kynurenine and its variations due to microbiota alterations with VAS in acute pain. Preoperative, postoperative, 8th-hour, and 24th-hour blood samples were routinely collected from patients, with 2 mL of sample material used each time. After the necessary centrifugation processes, the relevant laboratory team analyzed the kynurenine levels (ng/mL).

  Preoperative: Before surgery; Postoperative 8th-hour: 8 hours after surgery;Postoperative 24th-hour: 24 hours after surgery

• Tryptophan metabolites (Quinolinic Acid)

  2 mL of blood was used from the blood samples taken during routine surgery preparation for the patients and from the routine blood samples taken in the postoperative period, and no additional invasive intervention was performed. The investigator elucidated the relationship between quinolinic acid and its variations due to microbiota alterations with VAS in acute pain. Preoperative, postoperative, 8th-hour, and 24th-hour blood samples were routinely collected from patients, with 2 mL of sample material used each time. After the necessary centrifugation processes, the relevant laboratory team analyzed the quinolinic acid levels (ng/mL).

  Preoperative: Before surgery; Postoperative 8th-hour: 8 hours after surgery;Postoperative 24th-hour: 24 hours after surgery

• Tryptophan metabolites (Kynurenic Acid)

  2 mL of blood was used from the blood samples taken during routine surgery preparation for the patients and from the routine blood samples taken in the postoperative period, and no additional invasive intervention was performed. The investigator elucidated the relationship between kynurenic acid and its variations due to microbiota alterations with VAS in acute pain. Preoperative, postoperative, 8th-hour, and 24th-hour blood samples were routinely collected from patients, with 2 mL of sample material used each time. After the necessary centrifugation processes, the relevant laboratory team analyzed the kynurenic acid levels (ng/mL).

  Preoperative: Before surgery; Postoperative 8th-hour: 8 hours after surgery;Postoperative 24th-hour: 24 hours after surgery

• Tryptophan metabolites (Xanthurenic Acid)

  2 mL of blood was used from the blood samples taken during routine surgery preparation for the patients and from the routine blood samples taken in the postoperative period, and no additional invasive intervention was performed. The investigator elucidated the relationship between xanthurenic acid and its variations due to microbiota alterations with VAS in acute pain. Preoperative, postoperative, 8th-hour, and 24th-hour blood samples were routinely collected from patients, with 2 mL of sample material used each time. After the necessary centrifugation processes, the relevant laboratory team analyzed the xanthurenic acid levels (ng/mL).

  Preoperative: Before surgery; Postoperative 8th-hour: 8 hours after surgery;Postoperative 24th-hour: 24 hours after surgery

• Visual Analog Scale

  In VAS assessment, patients are typically asked to choose a value between "0, no pain" and "10, the worst imaginable pain." VAS is an 11-point scale (ranging from 0 to 10) that allows patients to numerically express the intensity of their pain. Blood samples were planned and collected from patients during the preoperative evaluation, at the 8th postoperative hour, and at the 24th postoperative hour, adhering to clinical routines for these procedures. Concurrently with each blood draw, the patient's VAS score, the nature of the pain, and vital signs were recorded.

  Preoperative: Before surgery; Postoperative 8th-hour: 8 hours after surgery;Postoperative 24th-hour: 24 hours after surgery

Secondary Outcomes (14)

• Systolic Blood Pressure (mmHg)

  Preoperative: Before surgery; Postoperative 8th-hour: 8 hours after surgery;Postoperative 24th-hour: 24 hours after surgery

• Diastolic Blood Pressure (mmHg)

  Preoperative: Before surgery; Postoperative 8th-hour: 8 hours after surgery;Postoperative 24th-hour: 24 hours after surgery

• Pulse Rate (beats per minute)

  Preoperative: Before surgery; Postoperative 8th-hour: 8 hours after surgery;Postoperative 24th-hour: 24 hours after surgery

• Respiratory Rate (breaths per minute)

  Preoperative: Before surgery; Postoperative 8th-hour: 8 hours after surgery;Postoperative 24th-hour: 24 hours after surgery

• Oxygen Saturation (%)

  Preoperative: Before surgery; Postoperative 8th-hour: 8 hours after surgery;Postoperative 24th-hour: 24 hours after surgery

Interventions

Pain Perception in Patients Undergoing Lumbar Disc Herniation Surgery PROCEDURE

Analyze tryptophan metabolites (picolinic acid, 3- Hydroxykynurenine, anthranilic acid, kynurenine, quinolinic acid, kynurenic acid, xanthurenic acid). Concurrent VAS pain assessments were conducted, and correlations between tryptophan metabolites and VAS were evaluated.

Also known as: Microbiota and Associated Blood Tryptophan Metabolites on

Eligibility Criteria

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

Study Population

Our study includes 37 lumbar disc herniation (LDH) surgeries performed in Dokuz Eylül University Faculty of Medicine Central Operating Rooms Brain and Nerve Surgery Hall. For the blood samples in which the investigators evaluated tryptophan metabolites; 2 mL of blood was used from the blood samples taken during routine surgery preparation for the patients and from the routine blood samples taken in the postoperative period, and no additional invasive intervention was performed. Concurrently with each blood draw, the patient's VAS score, the nature of the pain, and vital signs were recorded. Patient records, clinical histories, examination findings, and relevant laboratory results were electronically recorded.

You may qualify if:

• Patients undergoing lumbar disc herniation surgery at Dokuz Eylül University Hospital.
• Patients who have read and consented to the informed consent form for the study.
• Age 18 years or older.
• Surgery duration exceeding 2 hours.

You may not qualify if:

• Patients are unwilling to participate in the study.
• Surgery duration less than 2 hours.
• Patients under the age of 18.
• Patients with a history of abdominal surgery.
• Patients who received antibiotic therapy for intestinal pathology within the last 3 weeks.
• Patients with known abdominal pathologies suspected to alter the microbial flora (e.g., Crohn's disease, ulcerative colitis, celiac disease).

Sponsors & Collaborators

• Dokuz Eylul University: lead

Study Sites (1)

Yunu Çelik

Izmir, Balçova, 35100, Turkey (Türkiye)

Location

Related Publications (1)

• Celik Y, Aksu H, Gunenc FS, Kalemci O, Kizmazoglu C, Keskinoglu P. Association between circulating tryptophan metabolites and postoperative pain intensity in lumbar disc herniation surgery: An observational study. Medicine (Baltimore). 2025 Aug 1;104(31):e43704. doi: 10.1097/MD.0000000000043704.

  PMID: 40760513 DERIVED

MeSH Terms

Conditions

Pain, Postoperative; Acute Pain

Interventions

Microbiota

Condition Hierarchy (Ancestors)

Postoperative Complications; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Pain; Neurologic Manifestations; Signs and Symptoms

Intervention Hierarchy (Ancestors)

Microbiological Phenomena; Biota; Biodiversity; Ecosystem; Environment; Ecological and Environmental Phenomena; Biological Phenomena; Environment and Public Health

Study Officials

• Yunus Celik, M.D.

  Dokuz Eylül University Hospital, Faculty of Medicine

  STUDY CHAIR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Target Duration: 1 Year
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: June 28, 2024
• First Posted: July 16, 2024
• Study Start: January 12, 2022
• Primary Completion: November 24, 2022
• Study Completion: March 15, 2023
• Last Updated: July 16, 2024

Record last verified: 2024-07

Locations

TU (1)