Oxygen supplementation and adrenaline nebulization were started in view of possibility of bronchiolitis. Hemogram, serum electrolytes and renal function tests were normal. Chest X-ray revealed bilateral hyperinflation. After marginal improvement for two 2 days, his respiratory distress worsened. Salbutamol nebulization with oral prednisolone were started due to poor response to adrenaline nebulization. The respiratory distress did not respond and he was shifted to pediatric intensive care unit (PICU) for further management. In PICU, child continued to worsen (increasing respiratory distress and wheezing, oxygen saturation between 88-93%) and was treated with ipratropium nebulisation, intravenous (IV) hydrocortisone, terbutaline infusion, magnesium sulfate and aminophylline sequentially over 2 days. He was empirically administered IV antibiotic (amoxycilin-clavulanic acid), which was stopped after 3 days once blood culture was sterile. Arterial blood gas examination revealed compensated respiratory acidosis. On repeat chest X-ray, the hyperinflation persisted. The condition continued to deteriorate and on day three of PICU stay, IV ketamine was used as last measure before ventilation. It was given as 1 mg/kg bolus followed by continuous infusion at the rate of 10 µg/kg/min. The use of ketamine was not preceded by atropine. There was mild improvement. The ketamine infusion rate was increased to 15 µg/kg/min. At this dose he improved further; respiratory distress and wheezing decreased and oxygen saturation increased. The aminophylline, terbutaline and ketamine infusions were tapered off gradually in 48 hours. He did not require intubation and mechanical ventilation. No side effects of ketamine were noted during the course of therapy. He was shifted out of PICU after eight days of stay and was discharged from hospital after another two days.

The differential diagnoses of first-time wheezing in a 2-month old infant include: viral (bronchiolitis) or Chlamydial infection, congenital airway and heart anomalies, mediastinal masses and foreign body aspiration. There are no definite guidelines for the treatment of acutely wheezing infants. Betts, et al. [3] first reported use of ketamine in an asthmatic child in 1971. Since then, there are case reports/series and a few observational studies and randomised control trial (RCT) related to use of ketamine for acute exacerbation of asthma in pediatric age group (Web Table I). In these studies ketamine had been used for both nonventilated [3-6] and ventilated [7-9] children with benefits and there were either no or minor side effects. Ketamine has been used mostly for acute exacerbation of asthma, for patients who failed standard therapy except for study by Youssef-Ahmed, et al. [8] where it was also used for ventilated patients with severe bronchospasm due to Respiratory Syncytial Virus bronchiolitis (n=4) and bacterial pneumonia (n=2) (Web Table I). Ketamine, when used in nonventilated patients, obviated the need for mechanical ventilation [3-6], as seen in index case also. The present case is probably the youngest non-ventilated infant where ketamine was used successfully for bronchospasm. Earlier, ketamine was used for 8 months old ventilated infant for bronchospasm [8]. Ketamine had been used safely and effectively successfully for sedation in infants e.g. an 11 week old infant and infants with mean age of 6.1±3.1 months, range 8 days to 11 months [11]. One limitation of was the inability to test infant’s nasopharyngeal secretions for any viruses, especially respiratory syncytial virus, as this facility was not available at our centre.

To summarize, the use of ketamine in an infant with refractory wheezing due to bronchiolitis was successful and obviated need for intubation and mechanical ventilation. Well designed large randomized control trials are needed before recommending ketamine routinely for moderate to severe bronchospasm refractory to standard treatment in pediatric patients.

Contributors: KRJ had concept and design of manuscript. He will act as guarantor of the study. KRJ, CA and VG acquired data. KRJ reviewed the literature and drafted the article. CA and VG revised it critically for important intellectual content.

Funding: None; Competing interests: None stated.

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