gms | German Medical Science

61st Annual Meeting of the German Society of Neurosurgery (DGNC) as part of the Neurowoche 2010
Joint Meeting with the Brazilian Society of Neurosurgery on the 20 September 2010

German Society of Neurosurgery (DGNC)

21 - 25 September 2010, Mannheim

Experience with 521 operations in the sitting position: indication, complications and results

Meeting Abstract

  • Andreas Merkel - Neurochirurgische Klinik, Universitätsklinikum Erlangen, Germany
  • Tino Münster - Anästhesiologische Klinik, Universitätsklinikum Erlangen, Germany
  • Hubert Schmitt - Anästhesiologische Klinik, Universitätsklinikum Erlangen, Germany
  • Michael Buchfelder - Neurochirurgische Klinik, Universitätsklinikum Erlangen, Germany
  • Oliver Ganslandt - Neurochirurgische Klinik, Universitätsklinikum Erlangen, Germany

Deutsche Gesellschaft für Neurochirurgie. 61. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC) im Rahmen der Neurowoche 2010. Mannheim, 21.-25.09.2010. Düsseldorf: German Medical Science GMS Publishing House; 2010. DocP1732

doi: 10.3205/10dgnc203, urn:nbn:de:0183-10dgnc2037

Published: September 16, 2010

© 2010 Merkel et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.en). You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.


Outline

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Objective: The benefit of the sitting position for surgery of the posterior fossa and cervical spine is still matter of controversy. The literature suggests a decline in the use of this position in neurosurgery. However, there are undisputable advantages of the sitting position, such as the reduction of blood loss or reduced rate of brain swelling. In our study we analyzed the results in a large series. We compared the incidence of venous air embolism (VAE) as recognized with different monitoring techniques and the severity of complications.

Methods: We retrospectively analyzed 521 patients, who underwent surgery for different posterior fossa pathologies and cervical spine pathologies in the sitting position in our institution from 1995 to 2009. Intra operative monitoring for VAE included end-tidal CO2 level, Doppler ultrasound or intraoperative transesophageal echocardiography (TEE). We definded VAE as a decline of the end-tidal CO2 levels by more than 4 mm Hg, a characteristic sound in the thoracic Doppler or any sign of air in the TEE.

Results: We found an overall incidence of VAE in 15.2% of all patients, whereas the rate of severe complications associated with VAE such as a decline of pO2 or a drop of blood pressure was only 3.3%. Only two out of 521 operations had to be terminated because of non-controlable VAE (0.4%). There was no mortality resulting from VAE in this series. We also found a difference in the incidence of VAE depending on the monitoring technique. The VAE rate as monitored with TEE was 21% whereas the incidence of VAE in patients monitored with Doppler ultrasound was 12.8%. The rate of a significant VAE was comparable in both methods 12.5% vs. 10.1%. All patients were preoperatively screened for persisting foramen ovale (PFO). 21 patients with clinically confirmed PFO were included in this series. There was no case of paradox air embolism.

Conclusions: In our series, VAE was detected in 15.2% of all patients in the sitting position. However in only 0.4% was a termination of the surgical procedure needed. In all other cases, the cause of air embolism could be found and eliminated during surgery. TEE was found to be the monitoring technique with the highest sensitivity. In our opinion the sitting position is a safe positioning technique if TEE monitoring is used.