Effect of Patient Position on Arterial, End-tidal and Transcutaneous Carbon Dioxide

Study Overview
=================
Brief Summary
-----------------
Investigators evaluate the effect of patient position (Trendelenburg and reverse Trendelenburg) on arterial, end-tidal and transcutaneous carbon dioxide partial pressure in patients undergoing laparoscopic surgery.

Detailed Description
-----------------
Investigators evaluate the effect of patient position (Trendelenburg and reverse Trendelenburg) on arterial, end-tidal and transcutaneous carbon dioxide partial pressure in patients undergoing laparoscopic surgery. Arterial carbon dioxide partial pressure is assessed intermittently before, during, and after pneumoperitoneum. End-tidal and transcutaneous carbon dioxide partial pressure are continuously monitored.

Official Title
-----------------
Effect of Patient Position on Arterial, End-tidal and Transcutaneous Carbon Dioxide Partial Pressure in Patients Undergoing Laparoscopic Surgery

Conditions
-----------------
Ventilation Perfusion Mismatch

Intervention / Treatment
-----------------
* Other: Arterial carbon dioxide monitoring
* Other: End-tidal carbon dioxide monitoring
* Other: Transcutaneous carbon dioxide monitoring


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: adult patients undergoing laparoscopic surgery (expected duration of pneumoperitoneum > 1 hour) in the Trendelenburg or reverse Trendelenburg positions Exclusion Criteria: hemodynamically unstable patients due to decompensated heart failure, sepsis, or symptomatic arrhythmia, etc. symptomatic pulmonary disease, chronic obstructive pulmonary disease

Ages Eligible for Study
-----------------
Minimum Age: 20 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Other
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Trendelenburg group<br>Arterial, end-tidal, and transcutaneous carbon dioxide partial pressure are monitored in the Trendelenberg position | Other: Arterial carbon dioxide monitoring<br>* Arterial carbon dioxide partial pressure is monitored during the laparoscopic surgery undergoing in the Trendelenburg or reverse Trendelenburg positions.<br>Other: End-tidal carbon dioxide monitoring<br>* End-tidal carbon dioxide partial pressure is monitored during the laparoscopic surgery undergoing in the Trendelenburg or reverse Trendelenburg positions.<br>Other: Transcutaneous carbon dioxide monitoring<br>* Transcutaneous carbon dioxide partial pressure is monitored during the laparoscopic surgery undergoing in the Trendelenburg or reverse Trendelenburg positions.<br>|
| Active Comparator: reverse Trendelenburg group<br>Arterial, end-tidal, and transcutaneous carbon dioxide partial pressure are monitored in the reverse Trendelenberg position | Other: Arterial carbon dioxide monitoring<br>* Arterial carbon dioxide partial pressure is monitored during the laparoscopic surgery undergoing in the Trendelenburg or reverse Trendelenburg positions.<br>Other: End-tidal carbon dioxide monitoring<br>* End-tidal carbon dioxide partial pressure is monitored during the laparoscopic surgery undergoing in the Trendelenburg or reverse Trendelenburg positions.<br>Other: Transcutaneous carbon dioxide monitoring<br>* Transcutaneous carbon dioxide partial pressure is monitored during the laparoscopic surgery undergoing in the Trendelenburg or reverse Trendelenburg positions.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Difference between arterial and end-tidal carbon dioxide pressures | Difference between arterial and end-tidal carbon dioxide partial pressures are calculated. (Arterial carbon dioxide partial pressure minus end-tidal carbon dioxide partial pressure) | baseline before CO2 pneumoperitoneum, every 30 minute during CO2 pneumoperitoneum, and 15 min after deflation of CO2 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Agreement among arterial, end-tidal, and transcutaneous carbon dioxide partial pressure | Arterial, end-tidal, and transcutaneous carbon dioxide partial pressures are recorded and the agreement among the values is analyzed using the statistical test. | baseline before CO2 pneumoperitoneum, every 30 minute during CO2 pneumoperitoneum, and 15 min after deflation of CO2 |