Viral Croup

To Dr. Whitson: Thank you for bringing the 1-isomer epinephrine dose printed in the "Viral Croup" article to our attention. It is, as you correctly pointed out, a 5mL mixture of 1-isomer epinephrine and saline of the dilution 1:1000 and not the 1:100 dilution as printed, which has been used in the original study by Waisman (Pediatrics. 1992;89:302-306). I will add that another article, by Rosekrans (Mayo Coin Proc.1998;73:1102- 1107), also has the 1:100 dilution of 1-isomer epi and saline listed as the prescribed dose; however, on further referencing, this may be a mistake in their article as well.

To Dr. Feigelman: Comment 1: When comparing laryngotracheitis with epiglottis, the article states that in children who have acute laryngotracheitis, the epiglottis appears normal as opposed to that of the children who have epiglottitis. The definitive anatomic diagnosis of epiglottitis is made by visualization, however, and case management in this regard should be individualized. We agree with you and do not suggest randomly visualizing the epiglottis in severe/advanced cases of suspected epiglottitis without the proper setting or equipment.

Comment 2: We are sorry the x-ray was not clear to you. An arrow pointing to the enlarged epiglottis would have been helpful.

Comment 3: A PA film was what was done in this particular patient, as reported by the radiologist (Dr. Levenbrown). We do not believe that there is a consensus as to which is the x-ray of choice for croup, although airway AP views are possibly easier to obtain.

Comment 4: Although not specifically mentioned, a "well controlled environment" with "proper equipment" for intubation and laryngoscopy would, we hope, imply an OR or ICU setting.

Comment 5: Error noted. Depending on the degree of respiratory distress, intercostal retractions may be noted and can be relieved by nebulized racemic epinephrine (refer to viral croup article by Rosekrans, JA in Mayo Clin Proc 1998;73:1102-1107). However, in addition, supra- and infraclavicular as well as sternal retractions may be alleviated with the use of nebulized epinephrine.

Comment 6: The article states that IM dexamethasone is the steroid used most commonly to treat croup symptoms at a dose of 0.6 mg/kg. Other dexamethasone dosings that have been as effective include: 0.15/mg/kg IM x 1, or 0.3mg/kg IM x 1. The 1 mg/kg/day steroid dose given for 8 days for viral croup was used in an infant who subsequently developed C albicans laryngotracheitis. More information on this 1 case scenerio is found in the article, Candida laryngotracheitis: A complication of combined steroid and antibiotic usage in croup. Int J Pediatr Otorhinol. 1992;23:171-175.

We thank you for taking the time to send us your comments on our article, and we hope that the responses are helpful to you.

I have concerns about the article on croup in the January print issue: 1) The article suggests visualizing the epiglottis to make the correct diagnosis. That is never done as a diagnostic procedure. 2) The example of the lateral airway film is poor. 3) The article mentions the PA neck film, when in fact the AP is the x-ray of choice. 4) The article never mentions the necessity of bringing the child to the OR for sedation/intubation. 5) The effects of racemic epinephrine help the suprasternal and supraclavicular retractions. I suspect improvement in intercostal retractions are in error. 6) The dose of corticosteroids is given as 1/mg/kg/day. Does this refer to Dexamthasome or to another steroid? Thank you for attention to this.