Cerebral Blood Perfusion Changes After General Anesthesia for Craniotomy
Condition: Brain Neoplasms; Surgery; Hyperemia
MeSH terms: Brain Neoplasms; Hyperemia
Study type: Interventional

Summary: 
      Few studies look into cerebral blood flow (CBF) changes during emergence from general
      anesthesia for craniotomy. The purpose of this study is to demonstrate CBF changes during
      emergence from general anesthesia for craniotomy, through monitoring blood oxygen saturation
      of jugular vein bulb and transcranial Doppler.
    

Detailed description: 
      30 patients undergoing selective craniotomy (craniotomy group) for supratentorial brain tumor
      removal and 30 patients undergoing selective abdominal surgery (abdominal surgery group) are
      planned to be enrolled in the study. Mean blood flow velocity in middle cerebral artery
      (Vmca), mean arterial pressure (MAP), blood oxygen saturation of jugular vein bulb (SjvO2)
      (only measured in craniotomy group)and arterial CO2 partial pressure (PaCO2) will be measured
      before general anesthesia, at tracheal extubation, and 30,60, 90, 120 min after extubation in
      both groups.
    

Intervention name(s): Transcranial Doppler (TCD); jugular venous bulb catheterization; Tumor removal surgery under general anesthesia; Radial artery catheterization; Abdominal surgery under general anesthesia
Intervention type(s): Device; Procedure; Procedure; Procedure; Procedure
Intervention description(s): A 2-MHz Transcranial Doppler probe (MULTI-DOP P2.2C; DWL, Elektronische Systeme GmbH, Germany) will be used to measure both sides of Vmca of both patients undergoing craniotomy and patients undergoing abdominal surgery. The signal will be range-gated to a depth of 45 to 60 mm at temporal bone window to achieve the optimal signal according to standard techniques. The measures will be recorded in the operation room before anesthesia, in the recovery room at extubation, 30, 60, 90, and 120 min after extubation.; After local anesthesia, a jugular venous bulb catheter(16G, manufactured by Arrow International Inc. USA) will be placed in the dominant side. The proper placement of the tip of the catheter in the jugular bulb will be confirmed later by a postoperative lateral skull X-ray. SjvO2 (blood sample will be drawn slowly at a speed of 2ml per minute) will be measured before anesthesia, at extubation, 30, 60, 90, and 120 min after extubation.; Surgery types include total or subtotal removal of tumors.For all surgical procedures, general anesthesia will be maintained with isoflurane (0.5-1.0 minimal alveolar concentration (MAC) expired), repeated boluses of fentanyl (1~2 µg/kg IV), and continuous vecuronium 50～70 IV. All patients will be mechanical ventilated with oxygen. During anesthesia, blood pressure and heart rate will be kept stable, within ±10% of the preoperative levels. Hematocrit (Hct) will be maintained higher than 30%. After surgery, tracheal extubation will be performed when patients regain full muscle strength, breathe spontaneously with acceptable oxygenation and normocapnia.; After local anesthesia, an intra-arterial pressure line(I.V. catheter and pressure line kit are both manufactured by Smiths Medical International Ltd. USA) will be inserted in radial artery. Sample blood will be drawn from the line before anesthesia, at tracheal extubation, and 30, 60, 90, 120 min after tracheal extubation.; For all surgical procedures, general anesthesia will be maintained with isoflurane (0.5-1.0 minimal alveolar concentration (MAC) expired), repeated boluses of fentanyl (1~2 µg/kg IV), and continuous vecuronium 50～70 IV. All patients will be mechanical ventilated with oxygen. During anesthesia, blood pressure and heart rate will be kept stable, within ±10% of the preoperative levels. Hematocrit (Hct) will be maintained higher than 30%. After surgery, tracheal extubation will be performed when patients regain full muscle strength, breathe spontaneously with acceptable oxygenation and normocapnia.
Other intervention name(s): TCD; blood oxygen saturation of jugular vein bulb (SjvO2); craniotomy under general anesthesia
Intervention MeSH terms: Anesthetics
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Prevention
Keywords: Cerebral blood flow; Transcranial Doppler; Emergence from general anesthesia