Comparison of Propofol Requirement Between Patients With Pituitary Somatotroph Tumor and With Nonfunctioning Pituitary Tumor in Transsphenoidal Pituitary Surgery Under Total Intravenous Anesthesia

Study Overview
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Brief Summary
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Investigators hypothesized that propofol dose for pituitary somatotroph patients might differ from nonfunctioning pituitary tumor, and investigators will evaluate a target controlled infusion (TCI) effect site concentration (Ce) of propofol for BIS score of 40 and LOC (loss of consciousness) in pituitary somatotroph patients in comparison with non functioning pituitary tumor patients. On arrival in the operating room, standard monitoring devices, including electrocardiogram, pulse oximetry, noninvasive blood pressure cuff, and bispectral index (BIS) will be applied to the patients. Propofol with the modified Marsh pharmacokinetic parameters using a keo of 1.2/min will be administered through TCI pump (OrchestraBase Primea, Fresenius Vial, France). The initial target Ce of propofol will be chosen as 3.0 mg/mL (0.5 mg/mL of incremental size) based on an earlier study. The sedation of patients will be assessed with BIS score and the modified observer's assessment of awareness and sedation (OAA/S). LOC was defined as an OAA/S lower than 2 (loss of response to spoken command to eye opening and loss of response to mild prodding or shaking). The primary end point of this study is the Ce of propofol when the BIS score is 40. The secondary end point of this study is the Ce of propofol at LOC.

Official Title
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Comparison of Propofol Requirement Between Patients With Pituitary Somatotroph Tumor and With Nonfunctioning Pituitary Tumor in Transsphenoidal Pituitary Surgery Under Total Intravenous Anesthesia

Conditions
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Pituitary Tumor

Intervention / Treatment
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* Procedure: Not applicable (measuring subject's effect site concentration of propofol during the induction of general anesthesia)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients with pituitary somatotroph tumor and with nonfunctioning pituitary tumor in transsphenoidal pituitary surgery American society of anesthesiologists classification 1 or 2 Exclusion Criteria: left ventricle ejection fraction < 55% 3RD degree AV block, 2nd degree AV block with P:QRS > 3:1 serum Creatinine > 1.0mg/dl myocardial infarction or cerebral stroke in 1 yrs fever > 38C dementia, cognitive disorder, confused mental status pregnant patients allergic to propofol illiteracy or foreigners

Ages Eligible for Study
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Minimum Age: 19 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| patients with nonfunctioning pituitary tumor<br>patients with nonfunctioning pituitary tumor undergoing transsphenoidal pituitary surgery under total intravenous anesthesia | Procedure: Not applicable (measuring subject's effect site concentration of propofol during the induction of general anesthesia)<br>* The patients of two cohort group will undergo general anesthesia in the same way and therefore there is no intervention in this study.<br>|
| patients with pituitary somatotroph tumor<br>patients with pituitary somatotroph tumor undergoing transsphenoidal pituitary surgery under total intravenous anesthesia | Procedure: Not applicable (measuring subject's effect site concentration of propofol during the induction of general anesthesia)<br>* The patients of two cohort group will undergo general anesthesia in the same way and therefore there is no intervention in this study.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| effect site concentration of propofol | Investigators will assess the propofol requirement in pituitary tumor patients during the induction of general anesthesia when subject's BIS (Bispectral Index Score) is 40 | 5 minutes after subject's anesthesia induction | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| effect site concentration of propofol | Investigators will assess the propofol requirement in pituitary tumor patients during the induction of general anesthesia when the pituitary tumor patients lose their consciousness. | 2 minutes after subject's anesthesia induction |