Cerebral Blood Perfusion Changes After General Anesthesia for Craniotomy

Cerebral Hyperemia During Emergence From General Anesthesia for Craniotomy of Patients With Brain Tumor

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.

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.

Patients undergoing craniotomy who are scheduled for selective supratentorial tumor removal surgery will be randomly chosen and recruited. Transcranial Doppler (TCD) measures,jugular venous bulb catheterization, radial artery catheterization, and tumor removal surgery under general anesthesia will be performed.

Randomly chosen patients undergoing selective abdominal surgery. Transcranial Doppler (TCD) measures,radial artery catheterization, and major abdominal surgery under general anesthesia will be performed.

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.

after surgery at extubation (average surgery duration: craniotomy group 214min, abdominal group 207min)

Inclusion Criteria: American Society of Anesthesia (ASA) physical status I or II Scheduled for selective supratentorial tumor removal surgery or major abdominal surgery. Exclusion Criteria: Patients with evidence of systemic hypertension, intracranial hypertension, cerebrovascular diseases, other coexisting medical conditions likely to affect cerebral autoregulation. Preoperatively planned delayed tracheal extubation. Pregnant or nursing women

Rasmussen M, Juul N, Christensen SM, Jonsdottir KY, Gyldensted C, Vestergaard-Poulsen P, Cold GE, Ostergaard L. Cerebral blood flow, blood volume, and mean transit time responses to propofol and indomethacin in peritumor and contralateral brain regions: perioperative perfusion-weighted magnetic resonance imaging in patients with brain tumors. Anesthesiology. 2010 Jan;112(1):50-6. doi: 10.1097/ALN.0b013e3181c38bd3.

Randell T, Niskanen M. Management of physiological variables in neuroanaesthesia: maintaining homeostasis during intracranial surgery. Curr Opin Anaesthesiol. 2006 Oct;19(5):492-7. doi: 10.1097/01.aco.0000245273.92163.8e.

Clavier N, Schurando P, Raggueneau JL, Payen DM. Continuous jugular bulb venous oxygen saturation validation and variations during intracranial aneurysm surgery. J Crit Care. 1997 Sep;12(3):112-9. doi: 10.1016/s0883-9441(97)90040-x.

Bruder N, Pellissier D, Grillot P, Gouin F. Cerebral hyperemia during recovery from general anesthesia in neurosurgical patients. Anesth Analg. 2002 Mar;94(3):650-4; table of contents. doi: 10.1097/00000539-200203000-00031.

Rijbroek A, Boellaard R, Vriens EM, Lammertsma AA, Rauwerda JA. Comparison of transcranial Doppler ultrasonography and positron emission tomography using a three-dimensional template of the middle cerebral artery. Neurol Res. 2009 Feb;31(1):52-9. doi: 10.1179/174313208X325191. Epub 2008 Jul 25.

Sorond FA, Hollenberg NK, Panych LP, Fisher ND. Brain blood flow and velocity: correlations between magnetic resonance imaging and transcranial Doppler sonography. J Ultrasound Med. 2010 Jul;29(7):1017-22. doi: 10.7863/jum.2010.29.7.1017.

Macmillan CS, Andrews PJ. Cerebrovenous oxygen saturation monitoring: practical considerations and clinical relevance. Intensive Care Med. 2000 Aug;26(8):1028-36. doi: 10.1007/s001340051315.