Clinical Trial: Effects of the Prone and the Sitting Positions on the Brain Oxygenation in Posterior Fossa Surgery

Study Status: Not yet recruiting
Recruit Status: Not yet recruiting
Study Type: Interventional

Official Title: Effects of the Prone and the Sitting Positions on the Brain Oxygenation in Posterior Fossa Surgery

Brief Summary:

The sitting or prone positions are used for posterior fossa surgery. Although the sitting position may cause hemodynamic instability, venous air embolism, it also provides optimum access to midline lesions, decreases intracranial pressure. The sitting position has not been only used in neurosurgery, it has been also used in the shoulder surgery. The sitting position related hypotension may reduce the cerebral perfusion pressure, therefore may cause cerebral ischemia. The sitting position related cerebral ischemia has been shown in the shoulder surgery. The non invasive cerebral oxymetry (INVOS-Covidien) has been used to measure cerebral oxygen saturation. Some studies has been done to investigate whether the sitting position cause cerebral desaturation or not in the shoulder surgery by non invasive cerebral oxymetry. The study results are controversial.

It has been investigated that the effect of the prone position on the cerebral oxygenation in the spine surgery and the investigators found that the prone position may increase cerebral oxygenation.

However, all studies have been done in patients without intracranial pathology. We speculate that due to the sitting position reduces the intracranial pressure, it may improve the cerebral oxygenation in the patients have intracranial pathology. Therefore we will compare the sitting and the prone positions effects on the cerebral oxygenation in patients undergoing posterior fossa tumour surgery by non invasive cerebral oxymetry.

Method: 62 patients have posterior fossa tumour will include the study. Patients will divide to 2 groups according to the surgical position, the prone (n=31) or the sitting (n=31). Patients heart rate, mean blood pressure (MAP), cerebral oxygen saturation (SctO2), peripheral oxygen saturation (SpO2), BIS

Detailed Summary:

The sitting or prone positions are used for posterior fossa surgery. Although the sitting position may cause significant complications such as including hemodynamic instability, venous air embolism, paradoxical air embolism (PAE), pneumocephalus, peripheral neuropathy, quadriplegia and macroglossia, it also provides optimum access to midline lesions in posterior fossa and cervical spine, improves blood and cerebral spinal fluid drainage, decreases intracranial pressure, lowers airway pressure, and improves access to the endotracheal tube and ability to observe the face for signs of cranial nerves stimulations. The sitting position has not been only used in neurosurgery, it has been also used in the shoulder surgery. The sitting position related hypotension may reduce the cerebral perfusion pressure, therefore may cause cerebral ischemia. The sitting position related cerebral ischemia has been shown in the shoulder surgery.

The non invasive cerebral oxymetry (INVOS-Covidien) has been used to measure cerebral oxygen saturation. Some studies has been done to investigate whether the sitting position cause cerebral desaturation or not in the shoulder surgery by non invasive cerebral oxymetry. The study results are controversial.

It has been investigated that the effect of the prone position on the cerebral oxygenation in the spine surgery and the investigators found that the prone position may increase cerebral oxygenation.

However, all studies have been done in patients without intracranial pathology. We speculate that due to the sitting position reduces the intracranial pressure, it may improve the cerebral oxygenation in the patients have intracranial pathology. Therefore we will compare the sitting and the prone positions effects on the cerebral oxygenation in patients under
Sponsor: Istanbul University

Current Primary Outcome: Cerebral oxygen saturation [ Time Frame: Change from baseline cerebral oxygen saturation up to skin incision ]

After anesthesia induction cerebral oxygen saturation will record in each 3 minutes until the beginning of surgery


Original Primary Outcome: Same as current

Current Secondary Outcome:

Original Secondary Outcome:

Information By: Istanbul University

Dates:
Date Received: October 10, 2016
Date Started: November 2016
Date Completion: October 2018
Last Updated: October 13, 2016
Last Verified: October 2016