Pneumoperitoneum Duration and Bicarbonate Changes in Laparoscopic Hernia Surgery (TAPPHCO3)

Association Between Pneumoperitoneum Duration and Changes in Serum Bicarbonate Levels in Patients Undergoing Laparoscopic Inguinal Hernia Repair: A Prospective Observational Study

The goal of this observational study is to learn how the length of pneumoperitoneum during laparoscopic inguinal hernia surgery may affect changes in blood bicarbonate levels. Pneumoperitoneum is the use of carbon dioxide gas to create space inside the abdomen during laparoscopic surgery.

The main question this study aims to answer is whether a longer pneumoperitoneum time is associated with changes in blood bicarbonate levels after surgery.

Participants are adults undergoing laparoscopic inguinal hernia repair as part of their routine medical care. Researchers will measure blood gas values, including bicarbonate levels, before surgery and again two hours after surgery. The change in bicarbonate levels will be compared with the duration of pneumoperitoneum during the operation.

The results of this study may help improve the understanding of metabolic changes that occur during laparoscopic surgery.

Study Overview

• Status: Recruiting
• Conditions: Inguinal Hernia; Hernia, Inguinal
• Intervention / Treatment: Procedure: Laparoscopic Inguinal Hernia Repair (TAPP)

Detailed Description

Carbon dioxide pneumoperitoneum is routinely used during laparoscopic surgery to provide adequate visualization and working space. However, absorption of carbon dioxide and increased intra-abdominal pressure may influence acid-base balance during the perioperative period. These physiological changes may be reflected in blood gas parameters such as pH, partial pressure of carbon dioxide (pCO2), and serum bicarbonate levels.

This prospective observational study aims to evaluate the relationship between pneumoperitoneum duration and perioperative changes in serum bicarbonate levels in patients undergoing laparoscopic inguinal hernia repair using the transabdominal preperitoneal (TAPP) technique.

Adult patients undergoing elective laparoscopic inguinal hernia repair will be included in the study. Blood gas measurements will be obtained before surgery and at the second postoperative hour. Serum bicarbonate levels will be recorded, and the difference between preoperative and postoperative measurements (ΔHCO3-) will be calculated.

The primary outcome of the study is the change in serum bicarbonate levels between the preoperative and postoperative second-hour measurements. Secondary outcomes include postoperative pain scores, postoperative acid-base parameters such as pH and pCO2, and early postoperative complications within the first 24 hours.

Pneumoperitoneum duration will be recorded intraoperatively and analyzed for its association with perioperative metabolic changes. The findings of this study may contribute to a better understanding of metabolic alterations occurring during laparoscopic surgery and their potential clinical implications.

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

Contacts and Locations

• Study Contact: Name: Osman Sibic, MD; Phone Number: +90 534 617 72 53; Email: osmansibic@gmail.com
• Study Contact Backup: Name: Bahar Canbay Torun, MD; Phone Number: +90 505 389 0489; Email: baharcanbay@gmail.com

Study Locations

• Turkey (Türkiye)
  • Istanbul, Turkey (Türkiye), 34265
    • Recruiting
    • Haseki Training and Research Hospital
    • Contact: Bahar Canbay Torun, MD; Phone Number: +90 505 389 0489; Email: baharcanbay@gmail.com
    • Contact: Muzaffer Akinci, MD; Phone Number: +90 532 431 3613; Email: muzoakinci@hotmail.com
    • Principal Investigator: Muzaffer Akinci, MD

Participation Criteria

Eligibility Criteria

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

• Sampling Method: Non-Probability Sample

Study Population

Adult patients undergoing laparoscopic inguinal hernia repair (TAPP) at Haseki Training and Research Hospital will be included. Perioperative pneumoperitoneum duration and serum bicarbonate changes will be analyzed using blood gas measurements obtained preoperatively and at the second postoperative hour.

Description

Inclusion Criteria:

• Age ≥18 years
• Patients undergoing laparoscopic inguinal hernia repair using the TAPP technique
• Ability to provide informed consent

Exclusion Criteria:

• Pregnancy
• Severe cardiovascular disease
• Renal insufficiency
• Patients requiring additional intra-abdominal surgical procedures
• Strangulated inguinal hernia requiring bowel resection

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Laparoscopic Inguinal Hernia Patients; Adult patients undergoing laparoscopic inguinal hernia repair (TAPP). Pneumoperitoneum duration and perioperative serum bicarbonate changes will be analyzed using blood gas measurements obtained preoperatively and at the second postoperative hour.	Procedure: Laparoscopic Inguinal Hernia Repair (TAPP); Standard laparoscopic inguinal hernia repair performed using the transabdominal preperitoneal (TAPP) technique as part of routine clinical care. Pneumoperitoneum duration during the procedure will be recorded for analysis.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Serum Bicarbonate Level	Difference between preoperative and postoperative second-hour serum bicarbonate levels measured by blood gas analysis in patients undergoing laparoscopic inguinal hernia repair. Unit of Measure: mmol/L	Preoperative to postoperative 2 hours

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Postoperative Pain Score	Postoperative pain intensity measured using the Visual Analog Scale (VAS). The scale ranges from 0 to 10, where 0 indicates no pain and 10 indicates the worst imaginable pain. Higher scores represent greater pain severity. Unit of Measure: VAS score (0-10)	Within 24 hours after surgery
Change in Arterial Blood pH	Change in arterial blood pH measured during pneumoperitoneum. Unit of Measure: pH	Preoperative to postoperative 2 hours
Early Postoperative Complications	Early postoperative complications occurring within the first 24 hours after laparoscopic inguinal hernia repair.	Within 24 hours
Change in Arterial Partial Pressure of Carbon Dioxide	Change in arterial PaCO₂ levels measured intraoperatively. Unit of Measure: mmHg	Preoperative to postoperative 2 hours

Collaborators and Investigators

• Sponsor: Haseki Training and Research Hospital
• Investigators: Principal Investigator: Muzaffer Akinci, MD, Haseki Training and Research Hospital

Study record dates

Study Major Dates

• Study Start (Estimated): March 10, 2026
• Primary Completion (Estimated): April 1, 2026
• Study Completion (Estimated): May 1, 2026

Study Registration Dates

• First Submitted: March 6, 2026
• First Submitted That Met QC Criteria: March 12, 2026
• First Posted (Actual): March 16, 2026

Study Record Updates

• Last Update Posted (Actual): March 16, 2026
• Last Update Submitted That Met QC Criteria: March 12, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: Pneumoperitoneum; Laparoscopic Inguinal Hernia Repair; Blood Gas Analysis; Serum Bicarbonate; TAPP Technique
• Additional Relevant MeSH Terms: Pathological Conditions, Anatomical; Digestive System Diseases; Hernia; Peritoneal Diseases; Hernia, Abdominal; Pathological Conditions, Signs and Symptoms; Pneumoperitoneum; Hernia, Inguinal; tetra-4-amidinophenoxypropane
• Other Study ID Numbers: HASEKI-305-2025

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data will not be shared due to institutional data protection policies and patient confidentiality requirements. Only aggregated and anonymized data will be reported in scientific publications.

Drug and device information, study documents

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