Etco2 Levels on the End-tidal Concentration of Sevoflurane

Study Overview
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Brief Summary
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he assessment of adequate levels of anaesthesia traditionally relies not only on a patient's movement but also on the hemodynamic response (or both) to a surgical stimulus

Detailed Description
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Currently a derivative of MAC namely, end tidal partial pressure (FET) displayed on the work station as concentration , maybe an alternative useful measure of the anaesthetic effect of an inhaled anaesthetic agent . Many pharmacological factors have been associated with alterations in MAC and Mac derivatives such as nonsteroidal anti-inflammatory drugs (NSAIDs), analgesics, and anesthetics. However, few studies have focused on physiological factors, such as hypercarbia or hypocarbia. A correlation has been found between Paco2 and Etco2 in ventilated patients with healthy lungs. Some authors have suggested that Etco2 could be considered appropriate for estimating Paco2 even in critical patients. Knowledge of the effects of Paco2 on end tidal concentration of sevoflurane among patients undergoing laparoscopic cholecystectomy may help anaesthesiologists titrate sevoflurane carefully and precisely during different mechanical ventilation settings to avoid dose-dependent hypotension, impaired cardiac contractility, and hypothermia caused by excessive anaesthetic depth of sevoflurane.

Official Title
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The Effect of Different Etco2 Levels on the End-tidal Concentration of Sevoflurane in Patients Undergoing Laparoscopic Cholecystectomy

Conditions
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End-tidal Sevoflurane, End-tidal Carbon Dioxide, Minimum Alveolar Concentration

Intervention / Treatment
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* Procedure: low etco2
* Procedure: normal etco2
* Procedure: high etco2


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: American Society of anaesthesiologist ASA physical status I, II admitted for laparoscopic cholecystectomy Exclusion Criteria: Refusal of patients. Patients with renal or liver dysfunction. Patients with chronic pain other than cholelithiasis. Cardiac disorders as uncontrolled hypertension, arrhythmia, Ischaemic heart disease, valvular heart disease and pulmonary hypertension. Patient with haematological disorder as Sickle cell disease. Chest patient as asthma, COPD. Combined surgery . History of allergy to any of the study drugs. Patients with communication problems, cognitive dysfunction, or psychological disorders. Patients who received analgesics or sedatives 24 h before a scheduled surgery. Alcohol or drug abuse.

Ages Eligible for Study
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Minimum Age: 30 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: low ETCO2<br> | Procedure: low etco2<br>* Etco2 levels will be adjusted at levels ranging between 25 mm Hg and 30 mm Hg<br>|
| Active Comparator: normal ETCO2<br> | Procedure: normal etco2<br>* Etco2 levels will be adjusted at levels ranging between 31 mm Hg and 40 mm Hg<br>|
| Active Comparator: high ETCO2<br> | Procedure: high etco2<br>* Etco2 levels will be adjusted at levels ranging between 41 mm Hg and 45 mm Hg<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| end tidal concentration of sevoflurane | end tidal concentration of sevoflurane is measured by multiple gas analyser during operation | Total time of operation |