Proceedings of the NASS 20th Annual Meeting / The Spine Journal 5 (2005) 1S–189S 29S

Dana Piasecki, MD, Oheneba Boachie-Adjei, MD, Ashley Poynton, MD,Douglas Mintz, MD, Jeffrey Roh, MD, Margaret Peterson, PhD,Bernard Rawlins, MD, Gina Charles, BS; Hospital for Special Surgery,New York, NY, USA

BACKGROUND CONTEXT: While the risk of thromboembolic disease(TED) following spine operations is generally considered to be low,little study has focused on the potentially higher risk of TED after combinedanterior/posterior reconstructions. Conventional screening for deep venousthrombosis (DVT) cannot adequately detect pelvic DVT. Magnetic reso-nance venography (MRV) is the most effective means of detecting pelvicDVT but has never been used in spine patients.PURPOSE: The purpose of this study was to prospectively define theincidence of DVT following combined anterior/posterior spinal fusionsusing MRV as an adjunct to screening.STUDY DESIGN/SETTING: Prospective cohort study.PATIENT SAMPLE: 44 consecutive adult patients (mean age 52.4�

18.8 yrs) undergoing combined anterior/posterior spine reconstructions foradult spinal deformity were included. Patients were excluded for a historyof DVT or pulmonary embolus (PE), known coagulopathies, or a contraindi-cation to MRI.OUTCOME MEASURES: MRV and bilateral lower extremity Dopplerultrasounds were obtained postoperatively (mean 7.5 and 7.8 days,respectively).METHODS: In this prospective cohort study, 44 consecutive adult patients(mean age 52.4�18.8 yrs) undergoing combined anterior/posterior spinefusions were studied. Demographic, intraoperative (side of anterior ap-proach, number of units transfused), and postoperative (time to mobilization,etc.) data were recorded. All patients received only pneumatic compressionfoot pumps (Plexipulse) for DVT prophylaxis. MRV and bilateral lowerextremity Doppler ultrasounds were obtained postoperatively (mean 7.5and 7.8 days, respectively). Data were then analyzed using standardizedstatistical methods.RESULTS: The total incidence of postoperative DVT was 11.3% (5 pa-tients). The rate of pelvic DVT was 4.5% (2 patients), lower extremityDVT 6.8% (3 patients). PE developed in two patients (4.5%), both inconjunction with lower extremity DVT. All pelvic and lower extremity clotswere immediately treated with therapeutic anticoagulation. Both cases ofpulmonary emboli developed less than 48 hours after positive Dopplerstudies, and were subsequently treated with IVC filter placement. Thenumber of units transfused intraoperatively and a right-sided thoracoabdom-inal approach were associated with an increased risk of developing DVT ingeneral (p�.03, 0.02, respectively), and lower extremity DVT in particular(p�.002, 0.012, respectively).CONCLUSIONS: We report an elevated rate of pelvic and lower extremityDVT and PE following combined anterior/posterior spinal fusions. A sig-nificant proportion of DVTs in these patients arise in the pelvis. Intraopera-tive transfusion and a right-sided thoracoabdominal approach may representrisk factors for the development of postoperative DVT in this patient popula-tion. We recommend postoperative screening with Doppler ultrasound andMRV in these patients, with treatment initiated only after a positive study.Routine anticoagulation is not warranted for its known contribution topostoperative wound hematoma and neurologic sequelae.DISCLOSURES: No disclosures.CONFLICT OF INTEREST: No conflicts.

doi: 10.1016/j.spinee.2005.05.057

5:4356. Detection of esophageal perforation using intraesophagealdye injectionAlpesh Patel, MD1, Brett Taylor, MD2, Gbolahan Okubadejo, MD2,Todd Albert, MD3, K. Daniel Riew, MD2; 1Saint Louis, MO, USA;

2Washington University in St. Louis, MO, USA; 3Thomas JeffersonUniversity, Philadelphia, PA, USA

BACKGROUND CONTEXT: Esophageal perforation complicating ante-rior cervical spine surgery is a potentially fatal complication. Esophagealinjury is most commonly identified postoperatively with the developmentof abscess, tracheoesophageal fistula, or mediastinitis. Early, intraoperativedetection of injury allows for immediate treatment and improved outcomes.Currently, a technique of intraesophageal dye injection is clinically usedto detect esophageal perforations.PURPOSE: The purpose of this study is to assess the efficacy of intraeso-phageal dye injection to detect an esophageal injury and to test a noveltechnique. The hypothesis of this study is that intraesophageal injectionthrough a nasogastric tube does not give reliable detection of esophagealinjuries and that a new technique may improve visualization of theseinjuries.STUDY DESIGN/SETTING: A cadaveric study.PATIENT SAMPLE: Ten cadaveric head and neck specimens.OUTCOME MEASURES: The only outcome measure is the presence orabsence of a dye leak.METHODS: Standard anteromedial Smith-Robinson approach was usedto expose the anterior cervical spine. Each specimen was sequentiallytested by a control and three dye injection techniques: Technique A) Naso-gastric tube alone; Technique B) Nasogastric tube plus a distally placedFoley catheter; Technique C) Proximal plus a distally placed Foley catheter.Each technique was tested against esophageal perforations created byneedle puncture (21g, 18g, and 14g) and by a 2-mm high-speed burr. Dyevisualization was independently graded as present or absent by two authors.RESULTS: In the control trial, no dye leak was visualized in any of the10 specimens. In technique A, 9 of 40 perforations were visualized: 0 of 1021g perforations, 1 of 10 18g perforations, 2 of 10 14g perforations, and6 of 10 burr perforations. In technique B, 27 of 40 perforations werevisualized: 1 of 10 21g perforations, 8 of 10 18g perforations, 9 of 1014g perforations, and 9 of 10 burr perforations. Overall, 26 of 30 (87%)perforations size 18g or larger were detected. In technique C, 26 of 40perforations were visualized: 0 of 10 21g perforations, 9 of 10 18g perfora-tions, 10 of 10 14g perforations, and 7 of 10 burr perforations. Overall,26 of 30 (87%) perforations size 18g or larger were detected (Table 1).

Table 1Number of specimens with positive dye visualization bythree-intra-esophageal dye injection techniques

Tear size

Technique 21 g 18 g 14 g 2-mm burr

A 0 1 2 6B 1 8 9 9C 0 9 10 7

CONCLUSIONS: The study suggests that a current method of intraesopha-geal injection, nasogastric tube alone, is not an effective means of detectingesophageal perforation. Two novel techniques showed an improved capabil-ity of detecting esophageal perforations. Nevertheless, small perforationsremain undetected. Early identification of esophageal injury allows forimmediate treatment consisting of repair, drainage, and parenteral antibiot-ics. Serious sequelae of esophageal injuries may be avoided and patient mor-tality may be reduced by early surgical intervention.DISCLOSURES: FDA device/drug: Bard Foley Catheter Status: Not ap-proved for this indication.CONFLICT OF INTEREST: No conflicts.

doi: 10.1016/j.spinee.2005.05.058