1. Functional Endoscopic Evaluation vs Evan’s Blue Dye Test for Swallowing Assessment of Tracheostomised Patients Kynigou M. 1, Aggeli D. 1, Stefanidis A. 1, Triaridis A 1., Chatziavramidis A 2., Thomaidis J 1 1 ENT Dpt, ‘Theagenion’ Anti-cancer Hospital, Thessaloniki 2 ENT Dpt, Papageorgiou General Hospital, Thessaloniki INTODUCTION-PURPOSE Tracheotomy is among the most commonly conducted procedures in critically ill patients. The incidence of aspiration in patients with tracheotomy is 50-87% 1,2. The Evans blue dye test for aspiration in tracheotomised individuals was introduced by Cameron 3. The test is performed by placing drops of Evans blue dye on the patient’s tongue. The modified Evans blue dye test (MEBDT) introduces a slight variation on the original examination as described by Cameron. In the MEBDT, the patient is given blue dyed food and liquids. Since its introduction, almost 40 years ago, the blue dye test accuracy has been questioned. A new procedure has been recently introduced into the discipline of laryngology, using flexible endoscopy for assessing swallowing function: Fiberoptic Endoscopic Evaluation of Swallowing (FEES). The purpose of our project is to correlate FEES with Evan’s blue dye test used for clinical detection of aspiration in patients with tracheotomy. The purpose of our project is to correlate FEES with Evan’s blue dye test used for clinical detection of aspiration in patients with tracheotomy.PATIENTS-METHOD Forty-one individuals participated in this prospective study. They were tracheotomised patients in the Intensive Care Unit (ICU). All patients, 1-3 days before being discharged from ICU were checked with EBDT, MEBDT and FEES procedures. All procedures were conducted from the same laryngologist, with clinical and instrumental swallowing diagnostic experience. In EBDT, four drops of Evans blue dye were placed on the patient’s tongue and the trachea was suctioned at set intervals for coloured secretions. In MEBDT, different consistencies and different amounts of coloured food were given to the patients. The presence of coloured suctioned secretion suggested aspiration, i.e. a positive blue dye test, either EBDT or MEBDT. In EBDT, four drops of Evans blue dye were placed on the patient’s tongue and the trachea was suctioned at set intervals for coloured secretions. In MEBDT, different consistencies and different amounts of coloured food were given to the patients. The presence of coloured suctioned secretion suggested aspiration, i.e. a positive blue dye test, either EBDT or MEBDT. Within 24 hours the fiberoptic examination of swallowing (FEES) was administrated. FEES involves passing transnasally a fiberoptic laryngoscope in order to visualize the hypopharynx, larynx and proximal trachea for the purpose of assessing and treating swallowing function. In this procedure, a teaspoonful of creamy colored food and 2 to 5 cc of colored liquid are fed to the patient.The endoscopic presence of dye below the level of the true vocal cords signifies aspiration and positive FEES. RESULTS Purpose of this study was to correlate this new method (FEES) with the classic and modified Evans blue dye test in 41 ICU tracheotomised patients. Aspiration was present in 37 of the 41 (90,2%) FEES studies while aspiration was absent in the other 4 FEES studies. Aspiration was present in 30 of the 41 (73,2%) MEBDT tests and absent in the other 11 MEBDT tests. With FEES as the objective test of presence of aspiration, Evans blue dye test sensitivity and specificity identifying aspiration was 78% and 75% respectively. Positive prognostic value was 96, 6% and negative prognostic value was 27, 3%. DISCUSSION-CONCLUSIONS The limitations in swallowing function created by tracheostomy necessitate a high index of suspicion for aspiration to be maintained in all tracheotomised individuals. Evan’s blue dye (T-1824) is a diazo dye that has been used for determining the blood volume in humans and animals, named after Herbert McLean Evans, an American anatomist and physiologist at the University of California who published blood volume studies 4 Evan’s blue dye (T-1824) is a diazo dye that has been used for determining the blood volume in humans and animals, named after Herbert McLean Evans, an American anatomist and physiologist at the University of California who published blood volume studies 4 The EBDT and MEBDT are low cost bedside methods, easy to administrate, with no need for special expertise in endoscopy or expensive endoscopic equipment. The last 40 years the accuracy of blue dye test in documenting aspiration has been questioned. Thompson-Henry 5 reported the failure of MEBDT in detecting aspiration in five individuals. Brady et al 6 and Donzelli et al 7 reported a 50% false- negative error rate for the detection of trace aspiration amounts. Winklmeier et al 8 reported 95.24% sensitivity and 100% specificity when they performed MEBDT and FEES on thirty tracheotomised head and neck cancer patients. In our study the sensitivity and specificity of MEBDT in predicting aspiration was 78% and 75% respectively. We suggest that high positive prognostic value (96.6%), implies that when positive, Evans blue dye test should be evaluated, but when negative, endoscopic examination of swallowing should be performed in order to confirm the prior result. False negative results were present in our cohort in cases of laryngospasm, vocal cord paralysis and thick tracheal secretions in the aditus. The presence of nasogastric tube, allowing leaking of food around it into the larynx, was the only cause of false positive results. Fiberoptic Endoscopic Evaluation of Swallowing (FEES) is slightly invasive, easy to perform bedside procedure that can be easily repeated, gives us more accurate information and allows the clinician to identify the physiology of swallowing and determine the safe oral intake leading to decannulation of the tracheostomised patients. LITERATURE 1. Elpern E, Scott M, Ries P, Plumonary a spiration in mechanically ventilated patients with tracheotomies. Chest 105:563- 566, 1994 2. Pannunzio T Aspiration of oral feedings in patients with tracheotomies. AACN Clin Issues 7:560-569, 1996 3. Cameron J, Reynolds J, Zuidema G Aspiration in patients with tracheotomies. Surg Gynacol Obstet 136:60-70, 1973 4. Dawson A, Evans H, Wipple G Blood volume studies: behaviour of large series of dyes introduced into circulating blood. Am J Physiol 51:232, 1920 5. Thompson-Henry S, Braddock B. The modified Evan’s blue dye procedure fails to detect aspiration in the tracheostomized patient: five case reports. Dysphagia 10:172-174, 1995 6. Brady SL, et al. Simultaneous video- fluoroscopic swallow study and modified Evans blue dye procedure: an evaluation of blue dye visualization in cases of known aspiration. Dysphagia 14:146-149, 1999 7. Donzelli G, et al. Simultaneous modified Evans blue dye procedure and video nasal endoscopic evaluation of the swallow. Laryngoscope 111:1746-1750, 2001 8. Winklmaier U, et al. The accuracy of the modified Evans blue dye test in detecting aspiration in head and neck cancer patients. Eur Arch Otorhinolaryngol 264:1059-1064, 2007