Mode of Ventilation and Bleeding During Transsphenoidal Surgery

Study Overview
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Brief Summary
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The risk of bleeding is important during transsphenoidal surgery. This study aims to find if the ventilation mode, controlled pressure and controlled volume, modifies the risk of bleeding.

Detailed Description
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The risk of bleeding is important during transsphenoidal surgery. This study aims to find if the ventilation mode, controlled pressure and controlled volume, modifies the risk of bleeding. group Volume controlled ventilation: tidal volume of 7 mL/kg ideal body weight, frequency of 12 cycles/minute, I/E ratio of 1:2, no positive end expiratory pressure. Ventilatory frequency is changed if necessary to maintain end-expiratory pressure of CO2 between 35 and 40 mmHg. group Pressure-controlled ventilation: initial pressure of 15 cm H2O, frequency of 12 cycles/minute, I/E ratio of 1:2, no positive end expiratory pressure. Pressure is modified to maintain a tidal volume of 7 mL/kg of ideal body weight and frequency ventilation is modified to maintain end-expiratory pressure of CO2 between 35 and 40 mmHg. In both groups, the fraction of inspired oxygen is 50%. A recruitment maneuver is performed if the blood oxygen saturation became less than 92%.

Official Title
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Transsphenoidal Surgery for Pituitary Adenomas: Influence of the Ventilation Mode on Intraoperative Bleeding

Conditions
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Surgery

Intervention / Treatment
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* Procedure: Volume controlled ventilation
* Procedure: Pressure-controlled ventilation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Aged > 18 years Patients scheduled for transsphenoidal surgery for pituitary adenomas Exclusion Criteria: Pregnancy Obesity (BMI> 35) Known respiratory disease Redo surgery Preoperative problem with hemostasis (antiplatelet or anticoagulant treatment; constitutional disorder).

Ages Eligible for Study
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Minimum Age: 18 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Volume controlled ventilation<br>Volume controlled ventilation: tidal volume of 7 mL/kg ideal body weight, frequency of 12 cycles/minute, I/E ratio of 1:2, no positive end expiratory pressure. Ventilatory frequency is changed if necessary to maintain end-expiratory pressure of CO2 between 35 and 40 mmHg. | Procedure: Volume controlled ventilation<br> <br> |
| Experimental: Pressure-controlled ventilation<br>initial pressure of 15 cm H2O, frequency of 12 cycles/minute, I/E ratio of 1:2, no positive end expiratory pressure. Pressure is modified to maintain a tidal volume of 7 mL/kg of ideal body weight and frequency ventilation is modified to maintain end-expiratory pressure of CO2 between 35 and 40 mmHg | Procedure: Pressure-controlled ventilation<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| intraoperative bleeding | intraoperative bleeding is estimated by the operator (always the same) as minimal (1), low (3), with no significant change in the conduct of the surgical procedure (5) with significant change in the conduct of surgical procedure (7). Intermediate levels are used to rate the levels of intermediate severity. | 1 hour postoperatively | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| generated plateau pressures | mean ventilatory plateau pressure during surgery | one hour after surgery | 
| realisation of predefined objectives of minute ventilation | time spent with the predefined objectives of minute ventilation | one hour after surgery | 
| changes of ventilation mode | number of changes of ventilation mode | one hour after surgery | 
| arterial desaturation | number of episodes of arterial desaturation (SpO2 <92%) and lower arterial saturation during surgery | one hour after surgery | 
| recruitment maneuver | number of recruitment maneuver | one hour after surgery | 
| duration of the surgical procedure | duration from surgical incision to end of the surgical procedure | one hour after surgery | 
| endocrine healing | return to a low level of the abnormal endocrin abnormalities | three months after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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surgery, transsphenoidal surgery, pituitary adenoma, mechanical ventilation, bleeding