Cold air exposure for symptom relief in croup
Date First Published:
July 17, 2026
Last Updated:
July 17, 2026
Report by:
Dr James Manley, Paediatric teaching fellow (University Hospitals of Derby and Burton)
Search checked by:
Dr Graham Johnson, Paediatric emergency medicine consultant
Three-Part Question:
In [children with mild-to-moderate croup] does [exposure to outdoor cold air or low environmental temperature] improve [croup symptom severity]?
Clinical Scenario:
A 2-year-old child presents to the Emergency Department at 2 am with stridor at rest, mild-to-moderate intercostal recession, normal air entry on chest auscultation, normal oxygen saturations and a normal conscious level. You diagnose moderate croup. The parents report that the child's symptoms appeared to improve after being carried from the car park in the cool night air. You wonder whether there is evidence to support cold air exposure as a therapeutic intervention in children with croup.
Search Strategy:
Ovid MEDLINE (1946 to 16 June 2026) was searched on 16 June 2026 using the following strategy:
1. croup.mp. or exp Croup/
2. laryngotracheobronchitis.mp.
3. laryngotracheitis.mp.
4. 1 or 2 or 3
5. ((cold or cool or outdoor or night or fresh) adj3 (air or therap*)).mp.
6. cryotherapy.mp. or exp Cryotherapy/
7. exp Cold Temperature/
8. exp Hypothermia/
9. ("cold air" or "cool air" or "fresh air" or "night air").mp.
10. 5 or 6 or 7 or 8 or 9
11. (child* or paediatric* or pediatric* or infant* or toddler* or preschool*).mp.
12. exp child/ or exp infant/
13. 11 or 12
14. 4 and 10 and 13
1. croup.mp. or exp Croup/
2. laryngotracheobronchitis.mp.
3. laryngotracheitis.mp.
4. 1 or 2 or 3
5. ((cold or cool or outdoor or night or fresh) adj3 (air or therap*)).mp.
6. cryotherapy.mp. or exp Cryotherapy/
7. exp Cold Temperature/
8. exp Hypothermia/
9. ("cold air" or "cool air" or "fresh air" or "night air").mp.
10. 5 or 6 or 7 or 8 or 9
11. (child* or paediatric* or pediatric* or infant* or toddler* or preschool*).mp.
12. exp child/ or exp infant/
13. 11 or 12
14. 4 and 10 and 13
Search Details:
The search identified 209 records. Results were limited to journal articles, reviews and articles involving human paediatric populations, which identified 14 papers.
Outcome:
Titles and abstracts were screened for relevance to the clinical question. The references for these articles were then screened for any papers missed by the initial search. One randomised controlled trial directly evaluating inhaled outdoor cold air exposure in children with croup was identified and included in the evidence table (Siebert et al., 2023).
One additional randomised controlled trial evaluating cold fluid ingestion rather than inhaled cold air was identified but excluded from the primary evidence table as the intervention did not directly address the clinical question (Faraji-Goodarzi et al., 2018).
Observational literature describing prehospital management pathways incorporating environmental cold air exposure was reviewed and is discussed in the commentary but was not included in the primary evidence table owing to indirectness of the intervention and susceptibility to confounding (Cacchione et al., 2025).
One additional randomised controlled trial evaluating cold fluid ingestion rather than inhaled cold air was identified but excluded from the primary evidence table as the intervention did not directly address the clinical question (Faraji-Goodarzi et al., 2018).
Observational literature describing prehospital management pathways incorporating environmental cold air exposure was reviewed and is discussed in the commentary but was not included in the primary evidence table owing to indirectness of the intervention and susceptibility to confounding (Cacchione et al., 2025).
Relevant Paper(s):
| Study Title | Patient Group | Study type (level of evidence) | Outcomes | Key results | Study Weaknesses |
|---|---|---|---|---|---|
| Outdoor cold air versus room temperature exposure for croup symptoms: a randomized controlled trial Siebert, J.N., Salomon, C., Taddeo, I., Gervaix, A., Combescure, C. and Lacroix, L. 2023 Switzerland | 118 children aged 3 months to 10 years with croup (Westley Croup Score ≥2) | Randomised controlled trial (Level 1b) | Proportion achieving ≥2-point reduction in Westley Croup Score at 30 minutes | 49.2% (cold air) vs 23.7% (room temperature) achieved clinically significant improvement; greatest benefit seen in moderate croup (p < 0.001) | Open-label design; single-centre study; short follow-up period; uncertain duration of benefit; limited generalisability |
Author Commentary:
Evidence directly evaluating cold air exposure in croup remains limited. Although inhalation of cold air has been advocated for decades as a supportive treatment, it has rarely been formally evaluated (Moore and Little, 2007). The strongest available evidence comes from Siebert et al. (2023), a randomised controlled trial demonstrating a statistically and clinically significant short-term improvement in croup severity following brief exposure to outdoor cold air, particularly in children with moderate disease.
The study was open-label, single-centre and assessed only short-term outcomes, making the duration and generalisability of benefit uncertain. However, these limitations reflect some of the inherent challenges of studying environmental interventions, where standardising cold air exposure and blinding participants are difficult (Sibert er al., 2023).
Additional observational literature describes favourable outcomes associated with conservative prehospital management pathways incorporating environmental cold air exposure, although these studies are susceptible to confounding and do not isolate cold air as an intervention (Cacchione., et al 2025). Historical studies of cool mist and humidified air have also produced inconsistent findings (Neto et al., 2002; Moore and Little., 2007). As a simple, inexpensive and generally low-risk intervention, cold air exposure represents a reasonable target for future prospective study. Corticosteroids, particularly dexamethasone, remain the cornerstone of evidence-based treatment.
The study was open-label, single-centre and assessed only short-term outcomes, making the duration and generalisability of benefit uncertain. However, these limitations reflect some of the inherent challenges of studying environmental interventions, where standardising cold air exposure and blinding participants are difficult (Sibert er al., 2023).
Additional observational literature describes favourable outcomes associated with conservative prehospital management pathways incorporating environmental cold air exposure, although these studies are susceptible to confounding and do not isolate cold air as an intervention (Cacchione., et al 2025). Historical studies of cool mist and humidified air have also produced inconsistent findings (Neto et al., 2002; Moore and Little., 2007). As a simple, inexpensive and generally low-risk intervention, cold air exposure represents a reasonable target for future prospective study. Corticosteroids, particularly dexamethasone, remain the cornerstone of evidence-based treatment.
Bottom Line:
In children with mild-to-moderate croup, brief exposure to outdoor cold air may provide short-term improvement in symptoms, particularly in those with moderate disease, while awaiting the onset of corticosteroid effect (Siebert et al., 2023).
Cold air exposure is a reasonable, generally low-risk adjunct where practical and safe (for example, before hospital arrival or while awaiting assessment), but should not delay or replace treatment with dexamethasone.
Cold air exposure is a reasonable, generally low-risk adjunct where practical and safe (for example, before hospital arrival or while awaiting assessment), but should not delay or replace treatment with dexamethasone.
Level of Evidence:
Level 1: Recent well-done systematic review was considered or a study of high quality is available
References:
- Siebert, J.N., Salomon, C., Taddeo, I., Gervaix, A., Combescure, C. and Lacroix, L.. Outdoor cold air versus room temperature exposure for croup symptoms: a randomized controlled trial