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Ototoxic surgical preparation set to be the new standard
Otolaryngology–Head and Neck Surgery (2010) 142, 919-923
LETTERS TO THE EDITOR Ototoxic surgical preparation set to be the new standard A randomized trial published in January in The New England Journal of Medicine (NEJM) compared the effect of two skin preparation solutions on rates of surgical infections.1 The preparations that were compared were two percent chlorhexidine gluconate with 70 percent isopropyl alcohol and 10 percent povidone-iodine solution; the conclusion reached was that preoperative cleansing of a patient’s skin with chlorhexidine-alcohol was superior to cleansing with povidone-iodine for the prevention of surgical-site infection after clean contaminated surgery. The study did not include patients undergoing otologic surgery, but it is conceivable that hospitals will consider changing their policies on the provision of skin preparation solutions based on the reduction of infective complications as well as the lower cost of the chlorhexidine-alcohol solution. Although this makes sense for the types of surgery included in the NEJM study, it has been well demonstrated that both chlorhexidine and isopropyl alcohol solutions are ototoxic.2-4 This is not merely a theoretical risk to patients undergoing middle ear surgery, where the middle ear is open to the surgical preparation solution. A case series of 13 patients who sustained total cochleo-vestibular loss following the use of a preparation solution consisting of a mixture of 0.5 percent chlorhexidine and 70 percent isopropyl alcohol was published by Bicknell in 1971.5 More recently, a class action lawsuit was brought against a large Canadian hospital for sensorineural losses sustained after a policy change in surgical preparation solutions was introduced. The agent in question was a two percent chlorhexidine solution. In these times of budgetary constraints and adoption of evidence-based policies, it is important to remember that not all policies are safe to apply universally, and chlorhexidine-alcohol solutions should be kept out of the middle ear. David D. Pothier, MSc, MBChB, FRCS(ORL-HNS) John A. Rutka, MD, FRCSC Otolaryngology–Head and Neck Surgery Toronto General Hospital-University Health Network Toronto, Ontario, Canada E-mail, [email protected]
References 1. Darouiche RO, Wall MJ, Jr, Itani KM, et al. Chlorhexidine-alcohol versus povidone-iodine for surgical-site antisepsis. N Engl J Med 2010; 362:18 –26. 2. Spandow O, Anniko M, Moller AR. The round window as access route for agents injurious to the inner ear. Am J Otolaryngol 1988;9:327–35. 3. Aursnes J. Ototoxic effect of iodine disinfectants. Acta Otolaryngol 1982;93:219 –26.
4. Perez R, Freeman S, Sohmer H, et al. Vestibular and cochlear ototoxicity of topical antiseptics assessed by evoked potentials. Laryngoscope 2000;110:1522–7. 5. Bicknell PG. Sensorineural deafness following myringoplasty operations. J Laryngol Otol 1971;85:957– 61.
doi:10.1016/j.otohns.2010.02.035
In defense of the Nasal Obstruction Index In their report “Clinical assessment of adenoidal obstruction based on the Nasal Obstruction Index is no longer useful in children,”1 Marchisio et al challenge our conclusion that a Nasal Obstruction Index, obtained by averaging clinical ratings of mouth breathing and speech hyponasality, provides “reasonably valid assessments of the presence and degree of adenoidal obstruction.”2 Marchisio et al reported finding, instead, “no substantial agreement between the Nasal Obstruction Index and the degree of adenoidal obstruction.” There was, however, a crucial difference between the population we studied and the population studied by Marchisio et al. We excluded children with “any potentially confounding conditions, namely, upper respiratory tract infection, allergic or vasomotor rhinitis, and dental causes of lip separation.”2 In contrast, of the children studied by Marchisio et al, 53.0 percent reportedly had turbinate hypertrophy, and 23.8 percent had allergic rhinitis. By thus including children with conditions other than adenoidal hypertrophy that cause nasal obstruction, Marchisio et al foreordained that in their study population as a whole, correlations between the Nasal Obstruction Index and adenoidal hypertrophy specifically would be limited. Differences in sample size, disease prevalence, and the criterion standard used also likely contributed to differences in study outcomes. We studied 1033 children, of whom 33.1 percent had obstruction or borderline obstruction of the nasopharynx; Marchisio et al studied 202 children, of whom 81.7 percent had adenoid hypertrophy rated as grade 2 or higher. As the surrogate measure of functional nasopharyngeal obstruction, we used assessment of lateral soft-tissue roentgenograms, supported by tests of inter- and intraobserver reliability; Marchisio et al used findings on nasal fiberoptic endoscopy by a single observer. Because of the differences in their architecture, our study and the Marchisio et al study cannot be considered comparable. Accordingly, the fact that Marchisio et al found poorer concordance in their study population than we did in ours cannot be construed as refuting our findings. On the contrary, our findings clearly supported our proposing the Nasal Obstruction Index as a clinically useful tool for estimating the degree of adenoidal hypertrophy in children with no other apparent cause of nasal obstruction. In particular,
0194-5998/$36.00 © 2010 American Academy of Otolaryngology–Head and Neck Surgery Foundation. All rights reserved.
LETTERS TO THE EDITOR Ototoxic surgical preparation set to be the new standard A randomized trial published in January in The New England Journal of Medicine (NEJM) compared the effect of two skin preparation solutions on rates of surgical infections.1 The preparations that were compared were two percent chlorhexidine gluconate with 70 percent isopropyl alcohol and 10 percent povidone-iodine solution; the conclusion reached was that preoperative cleansing of a patient’s skin with chlorhexidine-alcohol was superior to cleansing with povidone-iodine for the prevention of surgical-site infection after clean contaminated surgery. The study did not include patients undergoing otologic surgery, but it is conceivable that hospitals will consider changing their policies on the provision of skin preparation solutions based on the reduction of infective complications as well as the lower cost of the chlorhexidine-alcohol solution. Although this makes sense for the types of surgery included in the NEJM study, it has been well demonstrated that both chlorhexidine and isopropyl alcohol solutions are ototoxic.2-4 This is not merely a theoretical risk to patients undergoing middle ear surgery, where the middle ear is open to the surgical preparation solution. A case series of 13 patients who sustained total cochleo-vestibular loss following the use of a preparation solution consisting of a mixture of 0.5 percent chlorhexidine and 70 percent isopropyl alcohol was published by Bicknell in 1971.5 More recently, a class action lawsuit was brought against a large Canadian hospital for sensorineural losses sustained after a policy change in surgical preparation solutions was introduced. The agent in question was a two percent chlorhexidine solution. In these times of budgetary constraints and adoption of evidence-based policies, it is important to remember that not all policies are safe to apply universally, and chlorhexidine-alcohol solutions should be kept out of the middle ear. David D. Pothier, MSc, MBChB, FRCS(ORL-HNS) John A. Rutka, MD, FRCSC Otolaryngology–Head and Neck Surgery Toronto General Hospital-University Health Network Toronto, Ontario, Canada E-mail, [email protected]
References 1. Darouiche RO, Wall MJ, Jr, Itani KM, et al. Chlorhexidine-alcohol versus povidone-iodine for surgical-site antisepsis. N Engl J Med 2010; 362:18 –26. 2. Spandow O, Anniko M, Moller AR. The round window as access route for agents injurious to the inner ear. Am J Otolaryngol 1988;9:327–35. 3. Aursnes J. Ototoxic effect of iodine disinfectants. Acta Otolaryngol 1982;93:219 –26.
4. Perez R, Freeman S, Sohmer H, et al. Vestibular and cochlear ototoxicity of topical antiseptics assessed by evoked potentials. Laryngoscope 2000;110:1522–7. 5. Bicknell PG. Sensorineural deafness following myringoplasty operations. J Laryngol Otol 1971;85:957– 61.
doi:10.1016/j.otohns.2010.02.035
In defense of the Nasal Obstruction Index In their report “Clinical assessment of adenoidal obstruction based on the Nasal Obstruction Index is no longer useful in children,”1 Marchisio et al challenge our conclusion that a Nasal Obstruction Index, obtained by averaging clinical ratings of mouth breathing and speech hyponasality, provides “reasonably valid assessments of the presence and degree of adenoidal obstruction.”2 Marchisio et al reported finding, instead, “no substantial agreement between the Nasal Obstruction Index and the degree of adenoidal obstruction.” There was, however, a crucial difference between the population we studied and the population studied by Marchisio et al. We excluded children with “any potentially confounding conditions, namely, upper respiratory tract infection, allergic or vasomotor rhinitis, and dental causes of lip separation.”2 In contrast, of the children studied by Marchisio et al, 53.0 percent reportedly had turbinate hypertrophy, and 23.8 percent had allergic rhinitis. By thus including children with conditions other than adenoidal hypertrophy that cause nasal obstruction, Marchisio et al foreordained that in their study population as a whole, correlations between the Nasal Obstruction Index and adenoidal hypertrophy specifically would be limited. Differences in sample size, disease prevalence, and the criterion standard used also likely contributed to differences in study outcomes. We studied 1033 children, of whom 33.1 percent had obstruction or borderline obstruction of the nasopharynx; Marchisio et al studied 202 children, of whom 81.7 percent had adenoid hypertrophy rated as grade 2 or higher. As the surrogate measure of functional nasopharyngeal obstruction, we used assessment of lateral soft-tissue roentgenograms, supported by tests of inter- and intraobserver reliability; Marchisio et al used findings on nasal fiberoptic endoscopy by a single observer. Because of the differences in their architecture, our study and the Marchisio et al study cannot be considered comparable. Accordingly, the fact that Marchisio et al found poorer concordance in their study population than we did in ours cannot be construed as refuting our findings. On the contrary, our findings clearly supported our proposing the Nasal Obstruction Index as a clinically useful tool for estimating the degree of adenoidal hypertrophy in children with no other apparent cause of nasal obstruction. In particular,
0194-5998/$36.00 © 2010 American Academy of Otolaryngology–Head and Neck Surgery Foundation. All rights reserved.