Mode of Ventilation and Bleeding During Transsphenoidal Surgery
Mode of Ventilation and Bleeding During Transsphenoidal Surgery
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.
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%.
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).