Intraoperative measurement of pharynx/esophagus retraction during anterior cervical surgery. Part I: pressure

Eur Spine J (2006) 15: 18331837DOI 10.1007/s00586-006-0069-0 ORIGINAL ARTICLE

Oliver Heese Frank Schroder Manfred Westphal Luca Papavero

Intraoperative measurement of pharynx/ esophagus retraction during anterior cervical surgery. Part I: pressure

Received: 3 August 2005Revised: 1 November 2005 Accepted: 10 January 2006 Published online: 14 February 2006 Springer-Verlag 2006

Abstract Temporary dysphagia after anterior cervical discectomy (ACD) is common. However, its mechanism is poorly understood. Pressure induced by retractor blades onto pharynx/esophagus were measured intraoperatively in order to gain more information regarding traumatization of the pharynx/ esophagus wall. Thirty-one patients underwent anterior cervical discectomy and fusion (ACDF) for degenerative disc disease. An online pressure transducer was applied to the rear side of the medial retractor blade (epi-esophageal-pressure, epiP) and a cylindric, inatable transducer was preoperatively inserted into the pharynx/esophagus under uoroscopic guidance at the level to be operated on (endo-esophageal-pressure, endo-P). Pressure values were recorded continuously during the operation. Mean arterial pressure (MAP) and endotracheal cu pressure (ETCP) were recorded additionally. An in vitro model was developed in order to analyze the impact of the retractor blade design onto the epi-esophageal-pressure. Mean epi-P before and following

adequate retractor opening for exposure of the disc space was 58.3 and 92.7 mmHg. Thirty, 60 and 90 min later the epi-P decreased to 79, 70 and 66%, respectively. Mean basal endo-P was 9.8 mmHg and increased to 20.6 mmHg after retractor placement. Thirty, 60 and 90 min later the endo-P decreased to 80, 71 and 62%, respectively. The mean MAP was 76 mmHg and the ECTP was adjusted to 25 mmHg during the procedures. In the in vitro model retraction pressure correlated inversely with the contact area between visceral wall and retractor blade. During ACDF the retraction pressure onto the pharyngeal/ esophageal wall exceeds MAP and even more the mucosal perfusion pressure of 25 mmHg. Over time the pharynx/esophageal wall adapts to the applied pressure induced by the retractor blade. The contact area between them inuences the retraction pressure.

Keywords Anterior cervical discectomy Dysphagia Pharynx Esophagus

Part II of this article can be found under http://dx.doi.org/10.1007/s00586-006-0070-7

O. Heese (&) F. SchroderM. Westphal Luca Papavero University Hospital Hamburg-Eppendorf, Hamburg, GermanyE-mail: [email protected].: [phone]Fax: [phone]

Introduction Anterior cervical discectomy (ACD) or anterior cervical discectomy and fusion (ACDF) is considered a safe procedure...