Skip Navigation

This Article
Right arrow Abstract Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrow Search for citing articles in:
ISI Web of Science (14)
Right arrowRequest Permissions
Right arrow Disclaimer
Google Scholar
Right arrow Articles by Brown, J. C
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Brown, J. C
Related Collections
Right arrow Respiratory Medicine
Right arrow Paediatric Medicine & Surgery
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

British Medical Bulletin 61:189-202 (2002)
© 2002 Oxford University Press

The management of croup

Julie C Brown

Divisions of General Academic Pediatrics, Department of Pediatrics, University of Washington School of Medicine, and Children's Hospital and Regional Medical Center, Seattle, Washington, USA


   Abstract
Top
 Footnotes
 Abstract
Introduction
 Evaluating therapies for croup
 Therapies for croup
 Future research
 Key points for clinical...
 Acknowledgements
 References
 
Croup is a common paediatric respiratory illness involving inflammation and narrowing of the subglottic region of the larynx, frequently precipitated by viral infections. Treatment is aimed at decreasing symptoms and reducing inflammation. Glucocorticoids are effective by oral, parenteral or nebulized routes, and continue to provide the mainstay of therapy. The common oral dexamethasone dose (0.6 mg/kg) may exceed the dose required for good clinical efficacy. Nebulized epinephrine provides effective additional therapy for more severe cases. L-epinephrine appears to be comparable to racemic epinephrine, although further study is warranted. Limited data suggest that heliox is also effective in the short-term management of refractory croup. The use of humidified oxygen remains controversial, as good data are lacking.


   Introduction
Top
 Footnotes
 Abstract
 Introduction
Evaluating therapies for croup
 Therapies for croup
 Future research
 Key points for clinical...
 Acknowledgements
 References
 
Croup is an acute respiratory illness caused by inflammation and narrowing of the subglottic region of the larynx. It manifests variously as a barking cough, hoarseness, stridor and respiratory distress, with or without concomitant symptoms of viral upper respiratory infection. Parainfluenza viruses account for most cases of viral croup, with types 1, 2 and 3 identified in three-quarters of all isolates1Go. Other aetiological agents include respiratory syncytial virus, influenza viruses A and B, and Mycoplasma pneumoniae. In general, the symptoms and signs of croup can be differentiated clinically from those of epiglottitis, foreign body aspiration and anatomical upper airway obstruction. When the diagnosis is uncertain, croup should be considered a diagnosis of exclusion, after appropriate evaluation for these alternate diagnoses.

Croup is a common childhood illness, resulting in 30 primary care visits per 1000 children per year in the US1Go. Fewer than 2% of cases are admitted to hospital and only 0.5–1.5% of these require intubation. Death from croup is rare, with mortality rates in intubated patients of less than 0.5%2Go. The total economic cost of croup is difficult to quantify. In the US, emergency visits and hospitalizations resulting from parainfluenza virus types 1 and 2 alone result in annual costs of $20 million and $56 million, respectively, and about 25% of these visits are due to croup3Go.

Traditionally, researchers emphasized differences between spasmodic (recurrent) croup and laryngotracheitis (viral croup). Some argued that spasmodic croup might be due to an allergic reaction to viral antigens rather than a direct result of a viral infection4Go. However, viral and spasmodic croup are poorly differentiated clinically, can both be associated with recent viral infections, and can have similar clinical presentations. The pathology of the two entities is the same5Go. For these reasons, most authors currently consider these two entities as part of a continual spectrum of disease6Go. Few clinical trials have differentiated between viral and spasmodic croup, so differences in treatment responsiveness by croup type are impossible to determine.

The management of croup has changed over the years, particularly with the development of new pharmacological therapies and increased evidence regarding treatment effectiveness. Pharmacological therapies generally aim to improve oxygenation, reduce airway narrowing and/or reverse the inflammatory process.


   Evaluating therapies for croup
Top
 Footnotes
 Abstract
 Introduction
 Evaluating therapies for croup
Therapies for croup
 Future research
 Key points for clinical...
 Acknowledgements
 References
 
Clinical studies of therapies for croup must have some measure of treatment efficacy. There is no single parameter that can be used as an accurate marker of clinical improvement. Researchers have developed croup scores, summarizing numerous symptoms and signs, as objective measures of clinical symptoms. A variety of croup scores have been devised, the most commonly used being the Westley and the modified Westley croup scores (Table 1).


View this table:
[in this window]
[in a new window]
  		Table 1 Croup scores

 
Ideally, croup scores should be consistent between different examiners (good inter-rater reliability), comparable to other measures of disease severity (good construct validity), and able to demonstrate anticipated decreases with effective therapy (good responsiveness to change). The validation of croup scores has been considered in four studies7GoGoGo–10Go. The Geelhoed score was twice assessed for inter-rater reliability. In the first study, triage nurse versus researcher assessments for 17 randomly selected patients were retrospectively compared. The weighted kappa was 0.85, indicating reasonable inter-observer agreement7Go. In the second study, two workers prospectively assigned croup scores to 15 children not in the clinical trial. The weighted kappa statistic was 0.878Go. The Syracuse croup score was tested prospectively on 165 croup patients in an intensive therapy unit (ITU) to assess how well scores below 6 predicted suitability of transfer from the ITU to the general wards (responsiveness to change).10Go The authors found that this score had 80% sensitivity and 100% specificity for testing suitability for transfer. The Westley croup score was evaluated with respect to inter-rater reliability, construct validity and responsiveness to change, using 54 patients with croup, none of whom had cyanosis or changes in level of consciousness.9Go It performed well in all areas of assessment. Inter-rater reliability between three research assistants was assessed prospectively. The weighted kappa was 0.90 for the total croup score, 0.47 for air entry, 0.93 for stridor and 0.87 for retractions. Construct validity was assessed by correlating the change in croup score during the course of treatment with other measures, including a parental global assessment of change (correlation coefficient, r = 0.51), the treating physician's global assessment of change (r = 0.51), the research assistant's global assessment of change (r = 0.76), length of time spent in the emergency department (r = 0.44), change in heart rate (r = 0.19) and change in respiratory rate (r = 0.32). Responsiveness to change was assessed by testing the sensitivity of the change in croup score to final patient disposition (mean [SD]) change in croup score was 1.7 (1.7) in patients discharged and 0.3 (1.0) in patients admitted, P = 0.006).


   Therapies for croup
Top
 Footnotes
 Abstract
 Introduction
 Evaluating therapies for croup
 Therapies for croup
Future research
 Key points for clinical...
 Acknowledgements
 References
 
Glucocorticoids – effectiveness

A systematic review published by the Cochrane collaboration11Go,12Go summarizes the numerous studies that have evaluated the effectiveness of glucocorticoids in attenuating the clinical course of croup. This systematic review is high quality evidence, level 1a, based on the Centre for Evidence Based Medicine's Levels of Evidence and Grades of Recommendations (http://cebm.jr2.ox.ac.uk/docs/levels.html). An update of this systematic review is expected within the next year.

Of the 29 trials included, 17 studied dexamethasone, 9 studied budesonide and 3 studied methylprednisolone. Patients ranged from 4 months to 12 years, with mean ages of 13–45 months. Fourteen trials involved in-patients and 10 trials involved out-patients. Most of the studies were small with a median of 40 (inter-quartile range 36, 60) patients. Overall, glucocorticoids were associated with a significant improvement in the croup score with an effect size of –1.0 (95% confidence interval [CI] –1.5, –0.6) at 6 h and –1.0 (95% CI, –1.6, –0.4), at 12 h (see Fig. 1). By 24 h, this improvement was no longer statistically significant, effect size –1.0 (95% CI, –2.0, 0.1). Compared with placebo-treated children, children treated with glucocorticoids were also statistically less likely to need epinephrine compared to those who did not receive glucocorticoids, with a decrease of 9% (95% CI, 2%, 16%) in the budesonide group and 12% (95% CI, 4%, 20%) in the dexamethasone group. Children receiving glucocorticoids also had significantly shorter stay in both in the emergency department, where stay was reduced by 11 (–18, –4) h and in the in-patient setting, where stay was reduced by 16 (–31, –1) h.



View larger version (13K):
[in this window]
[in a new window]
  		Fig. 1 Meta-analysis of randomized controlled trials according to type of corticosteroids and time of assessment. The pooled effect sizes of corticosteroids versus placebo (derived from the change in croup score using random effect models) are given with their 95% confidence intervals. Pooled estimates with significant heterogeneity among trials are marked with asterisks. Reprinted with permission from BMJ Publishing Group.

 
The authors of the meta-analysis assessed publication bias by a combination of graphical methods including funnel plots and a rank correlation test13Go. A funnel plot indicated the presence of publication bias, suggesting that smaller, statistically negative studies were not identified and subsequently included in this systematic review. The effect size of the primary outcome croup score varied by study size, with the largest effect size of –1.4 (95% CI, –2.3, –0.4) for the smallest trials (≤ 38 patients), and the smallest effect size of –0.5 (95% CI, –0.8, –0.2) for the largest trials (> 62 patients). However, there was still evidence of benefit in the largest trials that were the least vulnerable to publication bias.

This meta-analysis supports the use of corticosteroids in both the in-patient and the out-patient setting. These conclusions are supported by additional outcomes research: in a hospital that established a policy of mandatory dexamethasone therapy for all children admitted with croup, transfer rates to the intensive care unit dropped from 12% to 3%14Go.

Glucocorticoids – route of administration

Most studies involving corticosteroids used dexamethasone, which has the advantages of a long biological half-life (36–54 h)15Go. Traditionally, dexamethasone was given by intramuscular injection at a dose of 0.6 mg/kg. More recently, oral dexamethasone and nebulized budesonide have been evaluated as alternative routes of corticosteroid administration.

Six clinical trials have compared oral corticosteroids with placebo for the treatment of croup. All of these studies showed a positive effect of oral corticosteroids7Go,8Go,16GoGoGo–19Go. To compare directly oral and intramuscular administration of dexamethasone, Rittichier and Ledwith studied all children between 3 months and 12 years of age seen in the emergency department with moderate croup symptoms and less than 48 h of illness. Moderate croup was defined as a clinical syndrome of hoarseness or barky cough combined with a history of or presence of stridor at rest, and/or retractions. Enrolled children were randomized to receive dexamethasone 0.6 mg/kg by either the intramuscular or the oral route. There was allocation concealment at the time of randomization, although nurses and parents were subsequently aware of the medication route used. The physicians remained blinded, and parents were advised not to indicate how the medication was delivered. The primary outcome was the need for further therapy based on telephone follow-up at 48–72 h. Secondary outcomes were caretaker reports of improvement in or resolution of symptoms.

The researchers enrolled 277 children with a median age of 2.1 ± 1.8 years. All patients received telephone follow-up. Rates of unscheduled return visits in those who received an intramuscular injection (32%) and oral administration (25%) of dexamethasone were not statistically different: RR 0.78 (95% CI, 0.54–1.14). Rates of treatment failure (need for additional steroids, racemic epinephrine and/or hospitalization) were also similar between those who received intramuscular injection (8%) and oral (9%) administration.

Caretakers reported resolution of symptoms in 56% and 48% of patients who received intramuscular and oral administration of dexamethasone, respectively. Symptoms were improved in 42% and 47% of patients who received intramuscular and oral administration of dexamethasone, respectively. Oral administration of dexamethasone appears to be as effective for the treatment of croup as intramuscular administration, and is easier and cheaper to administer.

Glucocorticoids – nebulized

Numerous studies have compared nebulized budesonide with other routes of glucocorticoid administration. Geelhoed and Macdonald evaluated 80 patients over 3 months of age admitted to hospital with croup7Go. Patients were randomized to receive oral dexamethasone 0.6 mg/kg with nebulized saline placebo, nebulized budesonide 2 mg with oral placebo, or double placebo. The Geelhoed croup score was measured at 0, 1, 2, 3, 4, 8, 16, 20 and 24 h from study entry. Duration of admission, duration of croup score greater than 1, and use of racemic epinephrine were also measured. Although corticosteroid-treated children had improved outcomes over placebo treated children for all measured outcomes, there were no statistically significant differences in any outcomes for children in the oral dexamethasone and nebulized budesonide arms of the study.

Johnson et al20Go randomized 144 children aged 3 months to 9 years and with a Westley croup score of 3–6 to receive i.m. dexamethasone 0.6 mg/kg, nebulized budesonide 4 mg or nebulized placebo. All patients received nebulized racemic epinephrine. Hospitalization rates were measured, as well as changes in Westley croup score and need for additional racemic epinephrine. Rates of hospitalization after treatment were highest in the placebo group (67%), intermediate in the budesonide group (35%) and lowest in the dexamethasone group (17%). Unadjusted rates of hospitalization were not significantly different between the dexamethasone and budesonide groups (P = 0.18).

Klassen et al21Go evaluated 198 children aged 3 months to 5 years presenting to the emergency department with croup. Patients who had a croup score of 2 or greater following 15 min of mist therapy were randomized to receive oral dexamethasone 0.6 mg/kg with nebulized saline placebo, nebulized budesonide 2 mg with oral placebo, or both oral dexamethasone 0.6 mg/kg and nebulized budesonide 2 mg. The Westley croup score was measured at baseline and hourly until the patient received racemic epinephrine, had a croup score less than 2, had been discharged or had been observed for 4 h, whichever occurred first. All three therapies were equally effective in reducing the croup score from baseline. The estimated treatment difference between dexamethasone and budesonide was –0.12 (95% CI, –0.53, 0.29). There was no statistical difference in median time to discharge from the emergency department (127.5 min in the dexamethasone group versus 155 min in the budesonide group, P = 0.65). Co-intervention with racemic epinephrine was evenly distributed amongst the three groups. Physician follow-up for croup symptoms after discharge occurred in 27% of patients treated with dexamethasone, 60% of the patients treated with budesonide, and 38% of patients treated with both (P = 0.06). Only one patient, from the dexamethasone group, was subsequently hospitalized.

The evidence from these three studies suggests that aerosolized budesonide is an effective alternative to oral or i.m. dexamethasone for the management of croup. In additional research, Geelhoed noted that the oral medication was easier to administer to children with croup than the nebulized treatment, and that many children found the nebulized treatment distressing in its own right22Go. For this reason, he advocated the use of oral dexamethasone rather than inhaled budesonide.

Glucocorticoids – dosing

Regardless of administration route, the most commonly studied dexamethasone dose is 0.6 mg/kg, with a maximum dose of 10 mg. This dose is equal to a typical daily dose of dexamethasone for the treatment of meningitis, which is usually given as four divided doses23Go. It has equivalent glucocorticoid activity to approximately 6 mg/kg of prednisolone, and is arguably a larger dose than is needed for adequate treatment of croup15Go. Recently, the effectiveness of lower doses of oral dexamethasone have been evaluated. Two clinical trials by Geelhoed show that lower doses of dexamethasone are effective in the treatment of croup8Go,22Go. In his first randomized trial, Geelhoed evaluated 120 children greater than 3 months of age admitted for croup, over two separate study periods22Go. He compared dexamethasone 0.6 mg/kg with dexamethasone 0.3 mg/kg during the first study period (n = 60) and dexamethasone 0.3 mg/kg with dexamethasone 0.15 mg/kg during the second study period (n = 60). In both study periods, there were no differences and no trends towards differences in a six-point croup score at 1, 2, 3, 4 or 8 h post-treatment, nor were there differences or trends towards differences in duration of hospitalization or need for racemic epinephrine. These studies may have been too small to detect a clinically important difference in efficacy between the higher and lower dose groups.

Geelhoed also performed a randomized trial of 100 children over 3 months of age who were evaluated in an emergency department and treated as out-patients for croup with placebo or oral dexamethasone 0.15 mg/kg;8Go 96 children completed follow-up. None of the 48 children treated with dexamethasone and eight of the 48 children treated with placebo returned to care with continuing symptoms of croup (P < 0.01). Even if the 2 patients in the treatment group who were lost to follow-up had both sought further treatment, and the two in the placebo group had not, the relative risk of returning to care would be 4.0 times higher for the placebo-treated children compared with the dexamethasone treated children (95% CI, 0.89, 17.91).

Finally, Geelhoed published an observational study reporting adverse events in a hospital that switched from 0.6 to 0.15 mg/kg of oral dexamethasone for all croup patients other than those in intensive care14Go. In 1993, this hospital established a routine policy of administering a single oral dose of dexamethasone, 0.6 mg/kg, to all children admitted to the hospital with croup. This dose was decreased to 0.3 mg/kg and then 0.15 mg/kg after 1994. The intensive care admission and intubation rates fell dramatically after the introduction of steroids, but did not show an increase when the steroid dose was subsequently decreased. The number of children presenting with croup did not change during this time, and many came from other parts of the country where corticosteroids were not used. In summary, these three studies suggest that lower doses of dexamethasone are equally effective in reducing acute symptoms of croup.

Humidification

Treatment with moist air probably stems from the late 19th century, when parents used steam from tea kettles or hot tubs to treat croup in their children. Hospitals adopted the practice of ‘croup kettles’ long before clinical trials were routine6Go. The use of hot steam at home has never been studied, and there are case reports of scald injury resulting from this therapy24Go. Cool mist and humidified oxygen are used by some hospitals, although there are limited data to support their use. The only published randomized, controlled trial evaluating mist therapy in croup was a study of 16 children that compared delivery of 87–95% relative humidity for 12 h via a perspex covered cot, with no treatment25Go. The two groups were compared using the Westley croup score, plus pulse rate, respiratory rate, transcutaneous oxygen and transcutaneous carbon dioxide, at 0, 1, 2, 3, 4, 5, 6, and 12 h. The study failed to demonstrate statistically significant associations between the method of treatment and the above measurements. However, the study size was small, increasing the chance of missing a true difference between the two groups (beta error). In addition, the initial croup scores were low (means 3.75 and 3.00 for the humidity and control groups, respectively, out of a possible 17 points), limiting the potential for improvement with therapy.

There is a currently unpublished, blinded, randomized controlled pilot study of 27 patients comparing treatment with a Mist stick (humidified oxygen) to no treatment26Go. The groups were comparable at baseline, and both received 0.6 mg/kg (maximum 10 mg) of dexamethasone at the onset of mist therapy. Two patients in each group received racemic epinephrine. The two groups were compared using the Westley croup score, pulse rate, respiratory rate, transcutaneous oxygen at 0, 0.5, 1, 1.5 and 2 h. The study failed to demonstrate statistically significant associations between the method of treatment and croup score at any of the time intervals, or overall (P = 0.27). However, there was a consistent trend towards a decrease in croup score in the mist treated group (n = 13) compared with the no mist group (n = 14). Given the small numbers studied and the low initial croup scores (means 4 out of 17 points in each group), a true difference in effect may have been missed (beta error). The role of humidification remains unclear. Further study is in progress to evaluate this subject further.

Racemic epinephrine

There are four randomized trials comparing racemic epinephrine with either placebo27GoGo–29Go or no treatment30Go for the management of croup. Two additional studies include treatment arms where inhaled racemic epinephrine is compared to placebo31Go,32Go. A meta-analysis of these studies has not been done, and it would be difficult to combine the results since they all measured effectiveness at different times using different croup scores and allowing for different co-interventions. In some cases30GoGo–32Go, repeated epinephrine treatments were permitted as needed for continued symptoms. However, all seven studies showed significant improvements in croup score in the treated patients versus the controls, at one or more measured times during the course of the trials.

Traditionally, children with croup who were symptomatic enough to require racemic epinephrine treatment in addition to glucocorticoids were admitted to the hospital for observation, for concerns that their symptoms would relapse as the effect of epinephrine waned. In a randomized trial of nebulized racemic epinephrine administration, 35% of patients who received racemic epinephrine had a relapse of symptoms within 2 h of treatment33Go. Glucocorticoids were not given in this trial. No child was clinically worse 2 h after treatment than before treatment. More recently, out-patient management is being considered for a subset of emergency department patients who receive racemic epinephrine and dexamethasone and are asymptomatic following a period of observation. The optimal duration of observation following epinephrine treatment, to ensure that symptoms will not return, is uncertain, and the data are limited to two observational studies.

One prospective cohort study evaluated 174 children less than 13 years of age treated in an emergency department for moderate or severe croup34Go. Patients met study criteria if they were discharged from the emergency department after receiving a single dose of racemic epinephrine and dexamethasone 0.6 mg/kg (maximum 10 mg). Among 82 eligible discharged patients, 11 required follow-up within 48 h of discharge, 6 for croup and 5 for either asthma or bronchiolitis. One patient was lost to follow-up. Four patients required admission to hospital within 48 h, 2 for croup and 2 for bronchiolitis. The authors used their own croup score, and did not comment on the initial or discharge croup scores for those patients who returned to care.

In an additional prospective cohort study of 60 children aged 3 months to 6 years presenting to the emergency department with viral croup35Go, all eligible children received mist and intramuscular dexamethasone. Children with continued symptoms after 30 min received racemic epinephrine and were followed. Sixty children received racemic epinephrine, and 20 had continued symptoms and were admitted. All admitted patients who did not receive further racemic epinephrine treatments within 2 h (16/20) had modified Westley croup scores ≥ 2 at 2 h. Forty patients were discharged, 32 with a croup score of 0 or 1 and only 1 with a croup score of 3 (the remaining 7 presumably had a croup score of 2). Thirty-eight patients were followed-up. Two patients returned 32–36 h following racemic epinephrine treatment with worsening symptoms of croup and were admitted. The croup scores of these two patients at discharge were not mentioned. The sensitivity and specificity of the croup score at 2 h for predicting admission after observation for 4 h could not be determined from the data provided.

Although these studies are not conclusive, it appears that roughly 5% of patients discharged from the emergency department after receiving dexamethasone and racemic epinephrine for symptomatic croup will return to care. Relapse within 24 h is unlikely in patients with minimal symptoms (croup score 0–1) 2 h after racemic epinephrine treatment.

-epinephrine

The use of -epinephrine has been proposed as a less expensive and more readily available treatment for croup. Many practitioners who do not routinely stock racemic epinephrine have -epinephrine available as a resuscitation medication. One randomized controlled trial has compared -epinephrine, 5 mg of a 1:1000 dilution in normal saline with racemic epinephrine 0.5 cc of 2.25% (5 mg) in normal saline36Go. All patients aged 6 months to 6 years presenting with croup were evaluated and those with a Downes and Raphaely croup score of ≥ 6 after 20–25 min of mist therapy were included. Patients with a croup score > 8 or oxygen saturation < 95% also received i.m. dexamethasone. Sixteen patients were treated with racemic epinephrine and 15 with -epinephrine. Both groups had an initial improvement in croup score following treatment, but repeated measures ANOVA revealed no statistical differences in improvement between the two groups at 5, 15, 30, 60, 90 or 120 min following treatment. -epinephrine thus appears to be as efficacious as racemic epinephrine in the out-patient management of severe croup, although the number of patients studied is small and clinically important differences between the two groups could have been missed.

Heliox

Heliox is a metabolically inert, non-toxic gas that combines helium with oxygen. It has low viscosity and low specific gravity, which allows for greater laminar airflow through the respiratory tract37Go. It was first described by Barach for use in ameliorating airway obstruction associated with asthma, chronic obstructive pulmonary disease and upper airway disorders38Go. It has more recently been evaluated for use in the paediatric setting, for post-extubation stridor and croup. In a pilot study, Terregino et al randomized 15 children aged 6 months to 4 years with signs and/or symptoms of croup to receive either 30% humidified oxygen or heliox in a 70% helium/30% oxygen ratio39Go. Heliox was well tolerated and croup scores were similarly reduced in both groups (P = 0.32). The study may have been underpowered to detect important differences in efficacy between the two groups. Nelson et al followed 14 children between 3–21 months of age who were admitted to the ICU with severe croup and treated with heliox after failing to improve with racemic epinephrine. Glucocorticoids are not mentioned in the report. Rapid improvement in clinical symptoms was noted in 11 of the 14 patients immediately following heliox treatment40Go. Additional studies have shown benefit using heliox for post-extubation stridor41Go,42Go.

Heliox is commercially available in an 80% helium/20% oxygen ratio or a 70% helium/30% oxygen ratio, and is administered with a tight-fitting mask. The benefits improved laminar flow are lost if the gas holds more than 40% oxygen. The improvements in air exchange appear to outweigh this limitation. More studies are needed to determine better the indications for heliox therapy.


   Future research
Top
 Footnotes
 Abstract
 Introduction
 Evaluating therapies for croup
 Therapies for croup
 Future research
Key points for clinical...
 Acknowledgements
 References
 
There is limited evidence in many areas of croup therapy. In particular, studies have not clearly established the roles of humidified oxygen and lower doses of dexamethasone, or the optimal duration of observation following treatment with epinephrine. Further research is also needed to determine the efficacy of prednisolone versus dexamethasone for acute croup and the efficacy and safety of repeated doses of dexamethasone after 24 or 48 h, for patients with continued symptoms. Although we are likely to continue to manage croup for years to come, early intervention with corticosteroids and new therapies for severe disease will likely continue to lower morbidity and mortality due to this common childhood illness.


   Key points for clinical practice
Top
 Footnotes
 Abstract
 Introduction
 Evaluating therapies for croup
 Therapies for croup
 Future research
 Key points for clinical...
Acknowledgements
 References
 

  • • Glucocorticoids are the mainstay of therapy for croup
  • • Glucocorticoids can be given orally, parenterally or as nebulized medications
  • • Oral dexamethasone 0.6 mg/kg (maximum dose 10 mg) is commonly prescribed. Lower doses of oral dexamethasone, 0.3 mg/kg and 0.15 mg/kg appear to be equally effective
  • • There are insufficient data to evaluate the efficacy of humidification for the treatment of croup
  • • Nebulized epinephrine is an effective adjunctive therapy for the short-term treatment of respiratory distress due to croup
  • • -epinephrine appears to be as efficacious as racemic epinephrine
  • • Heliox appears to be an effective short-term treatment for refractive respiratory distress due to croup. It should be used in conjunction with glucocorticoids.


   Acknowledgements
Top
 Footnotes
 Abstract
 Introduction
 Evaluating therapies for croup
 Therapies for croup
 Future research
 Key points for clinical...
 Acknowledgements
References
 
This chapter summarizes and updates work presented previously in Moyer VA. (ed) Evidence Based Pediatrics and Child Health. London: BMJ Books, 2000.


   Footnotes
Top
 Footnotes
Abstract
 Introduction
 Evaluating therapies for croup
 Therapies for croup
 Future research
 Key points for clinical...
 Acknowledgements
 References
 
Correspondence to: Julie C Brown MD, Children's Hospital and Regional Medical Center, 4800 Sand Point Way NE, PO Box 5371/CH-04, Seattle, WA 98105-0371, USA


   References
Top
 Footnotes
 Abstract
 Introduction
 Evaluating therapies for croup
 Therapies for croup
 Future research
 Key points for clinical...
 Acknowledgements
 References
 

  1. Denny FW, Murphy TF, Clyde Jr WA, Collier AM, Henderson FW. Croup: an 11-year study in a pediatric practice. Pediatrics 1983; 71: 871–6[Abstract/Free Full Text]
  2. McEniery J, Gillis J, Kilham H, Benjamin B. Review of intubation in severe laryngotracheobronchitis. Pediatrics 1991; 87: 847–53[Abstract/Free Full Text]
  3. Henrickson KJ, Kuhn SM, Savatski LL. Epidemiology and cost of infection with human parainfluenza virus types 1 and 2 in young children. Clin Infect Dis 1994; 18: 770–9[Web of Science][Medline]
  4. Couriel JM. Management of croup. Arch Dis Child 1988; 63: 1305–8[Free Full Text]
  5. Cherry JD. The treatment of croup: continued controversy due to failure of recognition of historic, ecologic, etiologic and clinical perspectives [Editorial]. J Pediatr 1979; 94: 352–4[Web of Science][Medline]
  6. Skolnik N. Treatment of croup: a critical review. Am J Dis Child 1989; 143: 1045–9[Abstract/Free Full Text]
  7. Geelhoed G, Macdonald W. Oral and inhaled steroids in croup: a randomized, placebo-controlled trial. Pediatr Pulmonol 1995; 20: 355–61[Web of Science][Medline]
  8. Geelhoed GC, Turner J, Macdonald WB. Efficacy of a small single dose of oral dexamethasone for outpatient croup: a double blind placebo controlled clinical trial [see comments]. BMJ 1996; 313: 140–2[Abstract/Free Full Text]
  9. Klassen TP, Rowe PC. The croup score as an evaluative instrument in clinical trials. Arch Pediatr Adolesc Med 1995; 149: 60–1[Abstract/Free Full Text]
  10. Jacobs S, Shortland G, Warner J, Dearden A, Gataure PS, Tarpey J. Validation of a croup score and its use in triaging children with croup. Anaesthesia 1994; 49: 903–6[Web of Science][Medline]
  11. Ausejo MP, Saenz AM, Pham BM et al. Glucocorticoids for croup (Cochrane Review). In: The Cochrane Library, Issue 2, 2001. Oxford: Update Software
  12. Ausejo MP, Saenz AM, Pham BM et al. The effectiveness of glucocorticoids in treating croup: meta-analysis. BMJ 1999; 319: 595–600[Abstract/Free Full Text]
  13. Begg CB, Mazumdar M. Operating characteristics of a rank correlation test for publication bias. Biometrics 1994; 50: 1088–101[Web of Science][Medline]
  14. Geelhoed GC. Sixteen years of croup in a Western Australian teaching hospital: effects of routine steroid treatment. Ann Emerg Med 1996; 28: 621–6[Web of Science][Medline]
  15. Threlkeld DS. (ed) Drug Facts and Comparisons, 51st edn. 1997
  16. Tibballs J, Shann F, Landau L. Placebo-controlled trial of prednisolone in children intubated for croup. Lancet 1992; 340: 745–8[Web of Science][Medline]
  17. Novick A. Corticosteroid treatment of non-diphtheritic croup. Acta Otolaryngol 1960; 158 (Suppl): 20
  18. Muhlendahl K, Kahn D, Spohr H. Steroid treatment in pseudo-croup. Helv Paediatr Acta 1982; 37: 431[Web of Science][Medline]
  19. Martensson B, Nilson G, Torbjar J. The effect of corticosteroids in the treatment of pseudo-croup. Acta Otolaryngol 1960; 158 (Suppl): 20
  20. Johnson DW, Jacobson S, Edney PC, Hadfield P, Mundy ME, Schuh S. A comparison of nebulized budesonide, intramuscular dexamethasone, and placebo for moderately severe croup [see comments]. N Engl J Med 1998; 339: 498–503[Abstract/Free Full Text]
  21. Klassen TP, Craig WR, Moher D et al. Nebulized budesonide and oral dexamethasone for treatment of croup: a randomized controlled trial. JAMA 1998; 279: 1629–32[Abstract/Free Full Text]
  22. Geelhoed GC, Macdonald WB. Oral dexamethasone in the treatment of croup: 0.15 mg/kg versus 0.3 mg/kg versus 0.6 mg/kg. Pediatr Pulmonol 1995; 20: 362–8[Web of Science][Medline]
  23. McIntyre PB, Berkey CS, King SM et al. Dexamethasone as adjunctive therapy in bacterial meningitis. A meta-analysis of randomized clinical trials since 1988. JAMA 1997; 278: 925–31[Abstract/Free Full Text]
  24. Greally P, Cheng K, Tanner MS, Field DJ. Children with croup presenting with scalds. BMJ 1990; 301: 113[Free Full Text]
  25. Bourchier D, Dawson KP, Fergusson DM. Humidification in viral croup: a controlled trial. Aust Paediatr J 1984; 20: 289–91[Web of Science][Medline]
  26. Kentab O, Osmond M, Klassen T. A randomized controlled trial assessing the efficacy of mist sticks in the acute treatment of mild to moderate croup. 1999; Unpublished
  27. Gardner HG, Powell KR, Roden VJ, Cherry JD. The evaluation of racemic epinephrine in the treatment of infectious croup. Pediatrics 1973; 52: 52–5[Abstract/Free Full Text]
  28. Kristjansson S, Berg-Kelly K, Winso E. Inhalation of racemic adrenaline in the treatment of mild and moderately severe croup. Clinical symptom score and oxygen saturation measurements for evaluation of treatment effects. Acta Paediatr 1994; 83: 1156–60[Web of Science][Medline]
  29. Westley C, Cotton E, Brooks J. Nebulized racemic epinephrine by IPPB for the treatment of croup. Am J Dis Child 1978; 132: 484–7[Abstract/Free Full Text]
  30. Taussig LM, Castro O, Beaudry PH, Fox WW, Bureau M. Treatment of laryngotracheobronchitis (croup). Use of intermittent positive-pressure breathing and racemic epinephrine. Am J Dis Child 1975; 129: 790–3[Abstract/Free Full Text]
  31. Martinez Fernandez A, Sanchez Gonzalez E, Rica Etxebarria I et al. Estudio randomizado doble ciego del tratamiento del crup en la infancia con adrenalina y/o dexametasona. An Esp Pediatr 1993; 38: 29–32[Medline]
  32. Kuusela A, Vesikari T. A randomized, double-blind, placebo-controlled trial of dexamethasone and racemic epinephrine in the treatment of croup. Acta Paediatr Scand 1988; 77: 99–104[Web of Science][Medline]
  33. Fogel JM, Berg IJ, Gerber MA, Sherter CB. Racemic epinephrine in the treatment of croup: nebulization alone versus nebulization with intermittent positive pressure breathing. J Pediatr 1982; 101: 1028–31[Web of Science][Medline]
  34. Rizos JD, DiGravio BE, Sehl MJ, Tallon JM. The disposition of children with croup treated with racemic epinephrine and dexamethasone in the emergency department. J Emerg Med 1998; 16: 535–9[Medline]
  35. Kunkel NC, Baker MD. Use of racemic epinephrine, dexamethasone, and mist in the outpatient management of croup. Pediatr Emerg Care 1996; 12: 156–9[Web of Science][Medline]
  36. Waisman Y, Klein B, Boenning D et al. Prospective randomized double-blind study comparing L-epinephrine and racemic epinephrine aerosols in the treatment of laryngotracheitis (croup). Pediatrics 1992; 89: 302–6[Abstract/Free Full Text]
  37. McGee DL, Wald DA, Hinchliffe S. Helium-oxygen therapy in the emergency department. J Emerg Med 1997; 15: 291–6[Medline]
  38. Barach A. Use of helium in the treatment of asthma and obstructive lesions in the larynx and trachea. Ann Intern Med 1935; 9: 953–6
  39. Terregino CA, Nairn SJ, Chansky ME, Kass JE. The effect of heliox on croup: a pilot study. Acad Emerg Med 1998; 5: 1130–3[Web of Science][Medline]
  40. Nelson DS, McClellan L. Helium-oxygen mixtures as adjunctive support for refractory viral croup. Ohio State Med J 1982; 78: 729–30[Medline]
  41. Kemper KJ, Ritz RH, Benson MS, Bishop MS. Helium-oxygen mixture in the treatment of postextubation stridor in pediatric trauma patients. Crit Care Med 1991; 19: 356–9[Web of Science][Medline]
  42. Duncan PG. Efficacy of helium-oxygen mixtures in the management of severe viral and post-intubation croup. Can Anaesth Soc J 1979; 26: 206–12[Web of Science][Medline]

Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?



This Article
Right arrow Abstract Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrow Search for citing articles in:
ISI Web of Science (14)
Right arrowRequest Permissions
Right arrow Disclaimer
Google Scholar
Right arrow Articles by Brown, J. C
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Brown, J. C
Related Collections
Right arrow Respiratory Medicine
Right arrow Paediatric Medicine & Surgery
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?