Impact of Gut Microbiota and Tryptophan Metabolites on Acute Pain in Lumbar Disc Herniation Surgery Patients
NCT Number: NCT06502223
Status: COMPLETED
Study Type: OBSERVATIONAL
Conditions: Microbial Substitution|Tryptophan Metabolism Alterations|Postoperative Pain, Acute
Interventions: PROCEDURE: Pain Perception in Patients Undergoing Lumbar Disc Herniation Surgery
Sponsor: Dokuz Eylul University
Sex: ALL
Age: ADULT, OLDER_ADULT
Enrollment: 37
Study Design: Observational Model: |Time Perspective: p
Start Date: 2022-01-12
Completion Date: 2023-03-15
Locations: Yunu Çelik, İzmir, Balçova, 35100, Turkey

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).

Primary Outcome Measures: 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 Outcome Measures: Systolic Blood Pressure (mmHg), The study measured the systolic blood pressure (mmHg) of patients at specified time points.The patients' systolic blood pressure data were recorded simultaneously with the blood samples taken during routine surgery preparation and at the 8th and 24th hours postoperatively., Preoperative: Before surgery; Postoperative 8th-hour: 8 hours after surgery;Postoperative 24th-hour: 24 hours after surgery|Diastolic Blood Pressure (mmHg), The study measured the diastolic blood pressure (mmHg) of patients at specified time points.The patients' diastolic blood pressure data were recorded simultaneously with the blood samples taken during routine surgery preparation and at the 8th and 24th hours postoperatively., Preoperative: Before surgery; Postoperative 8th-hour: 8 hours after surgery;Postoperative 24th-hour: 24 hours after surgery|Pulse Rate (beats per minute), The study measured patients' pulse rate (beats per minute) at specified time points.The patients' pulse data were recorded simultaneously with the blood samples taken during routine surgery preparation and at the 8th and 24th hours postoperatively., Preoperative: Before surgery; Postoperative 8th-hour: 8 hours after surgery;Postoperative 24th-hour: 24 hours after surgery|Respiratory Rate (breaths per minute), The study measured the respiratory rate (breaths per minute) of patients at specified time points.

The patients' respiratory rate data were recorded simultaneously with the blood samples taken during routine surgery preparation and at the 8th and 24th hours postoperatively., Preoperative: Before surgery; Postoperative 8th-hour: 8 hours after surgery;Postoperative 24th-hour: 24 hours after surgery|Oxygen Saturation (%), The study measured patients' oxygen saturation (%) at specified time points.The patients' oxygen saturation data were recorded simultaneously with the blood samples taken during routine surgery preparation and at the 8th and 24th hours postoperatively., Preoperative: Before surgery; Postoperative 8th-hour: 8 hours after surgery;Postoperative 24th-hour: 24 hours after surgery|Nature of Postoperative Pain Assessed by the McGill Pain Questionnaire (MPQ), The McGill Pain Questionnaire (MPQ) was used to evaluate and categorize the nature of pain. The study assessed the nature and quality of acute postoperative pain using the McGill Pain Questionnaire (MPQ) at specified time points. Although all of the patients' pain was acute postoperative pain, the pain qualities were recorded simultaneously, taking into account the differences in pain qualities. The MPQ was used to evaluate and categorize the nature of pain. The MPQ includes descriptors of pain which are categorized into sensory, affective, evaluative, and miscellaneous dimensions. Each descriptor is rated on an intensity scale of 0 (none) to 3 (severe), and scores are summed to provide an overall pain score. Higher scores indicate worse pain., Preoperative: Before surgery; Postoperative 8th-hour: 8 hours after surgery;Postoperative 24th-hour: 24 hours after surgery|Comorbidity Assessment in Relation to Pain and Tryptophan Metabolites, The study recorded patients' comorbidities, specifically those identified during the preoperative anamnesis process, and evaluated their potential impact on the nature of pain and tryptophan metabolites. Comorbidities identified as exclusion criteria, particularly those believed to affect intestinal microbiota and related to abdominal conditions, were also considered. Patients' comorbidities identified during the preoperative anamnesis process were meticulously documented to assess their influence on pain characteristics and tryptophan metabolites. Additionally, comorbidities identified as exclusion criteria due to their potential to alter intestinal microbiota and their association with abdominal conditions were thoroughly evaluated., Preoperative anamnesis process: Prior to surgery, during patient assessment, Follow-up: Through study completion, an average of 1 year|Anesthesia induction drugs, Although standardization of drugs used in anesthesia is difficult, standardization of induction drugs was partially achieved because the investigators chose a single surgery group. The investigators recorded all of this data during anesthesia applications., During anesthesia procedure|Anesthesia duration and surgery times, Our study detailedly recorded the duration of anesthesia and surgery. To ensure a certain level of standardization, we included only lumbar disc surgery, which is considered sterile. Additionally, surgeries shorter than a specified duration were excluded as they might not provide significant metabolic changes. These durations were carefully recorded throughout the entire surgery and anesthesia period. The investigators accepted these durations as one of the elimination criteria due to their potential impact on pain and physiological mechanisms., During surgery|Age of Investigator, The investigator's age was recorded during the preoperative anamnesis process to understand its influence on the study variables., Preoperative: During the preoperative anamnesis process|Weight of Investigator, The weight of the investigator was recorded during the preoperative anesthesia process to understand its influence on the study variables., Preoperative: During the preoperative anamnesis process|Height of Investigator, The height of the investigator was recorded during the preoperative anamnesis process to understand its influence on the study variables., Preoperative: During the preoperative anamnesis process|Body Mass Index (BMI) of Investigator, The Body Mass Index (BMI) of the investigator was calculated from recorded height (in meters) and weight (in kilograms) during the preoperative anamnesis process to understand its influence on the study variables.BMI values are reported in units of kg/m²., Preoperative: During the preoperative anamnesis process|Gender of Investigator, The gender of the investigator was recorded during the preoperative anamnesis process to understand its influence on the study variables., Preoperative: During the preoperative anamnesis process