Otolaryngology: Open Access
Open Access

Abstract

The essential condition for precise and efficient endoscopic surgery of the praranasal sinuses and the skull base is good visualization of the surgical field which depends mainly on the intraoperative bleeding intensity. Besides local application of vasoconstrictors and putting the patient in the reverse Trandelenburg position reduction of the intraoperative bleeding is usually achieved by decrease of hemodynamic parameters of the operated patients. Maintenance of slow heart rate and low blood pressure is commonly practiced during endoscopic operations and is generally considered safe in healthy patients. However due to low invasiveness of endoscopic methods more and more elderly patients with comorbidities are qualified for this type of surgery and apparently, these patients are not likely to tolerate decreased hemodynamic parameters as well as young healthy persons do. Because insufficient brain perfusion is a main hazard of systemic hypotension we assessed blood flow velocity (BFV) in the middle cerebral artery (MCA) with transcranial color Doppler sonography during endoscopic procedures. The sonographic assessments were performed during the surgery, at the time when satisfactory bloodless surgical field was achieved due to reduced blood pressure and heart rate. It appeared that even a moderate reduction of blood pressure and HR for improving surgical field conditions resulted in some patients in a profound decrease in blood flow velocity in MCA to values well below the normal reference range. In order to assess possible metabolic consequences of controlled hypotension and decrease in cerebral blood flow velocity during endoscopic operations, we determined pre- and postoperative serum concentrations of neuron specific enolase (NSE) - marker suggestive for neural tissue damage. Although no patient suffered any neurological complications after surgery we found correlation between the postoperative rise of NSE level and the drop of blood flow velocity in MCA during the surgery. This fact may be suggestive for a minor and/or regional ischemic injuries to the brain may in these patients. The fact that bloodless surgical field during endoscopic transnasal operations may denote significant decrease of brain perfusion should be well known by both otolaryngologist and anesthesiologist and precaution is warranted while attempting to maintain dry surgical field especially during long lasting procedures.

Biography

Andrzej Sieskiewicz received PhD from the Medical Academy of Bialystok upon the presentation of Doctoral dissertation in 2000. He is a member of Polish Society of Otolaryngologists Head and Neck Surgeons, Polish Society of Skull Base Surgeons, Polish Rhinologic Society. He is author of over 70 publications in medical journals. He is an invited lecturer on polish and international conferences and teaching courses on endoscopic surgery of the nose, paranasal sinuses, skull base and orbit. He is the head of many scientific and research projects sponsored by Medical University of Bialystok and Polish Ministry of Science and Education focused mainly on endoscopic surgery and interdisciplinary cooperation during skull base pathology treatment.