European Journal of Cardiovascular Medicine

Acute bronchiolitis is one of the most frequent lower respiratory tract infections in infants and young children, particularly affecting those under two years of age, with a peak incidence in the first six months of life (1). It is predominantly caused by viral pathogens, with respiratory syncytial virus (RSV) being the leading etiological agent globally (2). Clinically, bronchiolitis is characterized by nasal congestion, cough, wheezing, increased respiratory effort, and in severe cases, hypoxia and dehydration (3).

Despite the significant burden it poses on pediatric healthcare systems, the management of acute bronchiolitis remains largely supportive. Current guidelines emphasize oxygen therapy, hydration, and minimal handling, while discouraging routine use of bronchodilators, corticosteroids, or antibiotics due to inconsistent efficacy (4,5). This lack of definitive pharmacologic therapy has prompted the exploration of alternative approaches that could potentially shorten illness duration and reduce hospitalization.

Nebulized hypertonic saline (usually 3%) has been proposed as a promising therapeutic option due to its ability to draw fluid into the airway lumen, reduce mucosal edema, and enhance mucociliary clearance (6). Some clinical trials and meta-analyses have suggested that hypertonic saline may lead to faster symptom resolution and decreased hospital stay in infants with bronchiolitis (7,8). However, its adoption into routine practice remains variable due to mixed results across studies and limited region-specific data, especially in low-resource settings.

This prospective study aims to evaluate the efficacy of 3% hypertonic saline nebulization compared to 0.9% normal saline in infants with acute bronchiolitis in a tertiary care hospital, focusing on clinical severity scores, oxygen requirement, and duration of hospitalization.

This prospective, randomized, controlled study was conducted in the Department of Pediatrics at a tertiary care teaching hospital over a period of six months.

Inclusion and Exclusion Criteria
Infants aged between 1 month and 12 months who presented with their first episode of clinically diagnosed acute bronchiolitis, based on symptoms such as cough, wheezing, chest retractions, and respiratory distress, were eligible for inclusion. Exclusion criteria included infants with underlying chronic lung disease, congenital heart anomalies, immunodeficiency, prior episodes of wheezing, or those requiring immediate intensive care.

Study Groups and Intervention
A total of 60 infants who fulfilled the inclusion criteria were randomly assigned into two groups using a computer-generated randomization sequence.

• Group A (Intervention Group) received nebulization with 3% hypertonic saline (3 ml) every 8 hours.
• Group B (Control Group) received nebulization with 0.9% normal saline (3 ml) at the same frequency.

Nebulizations were administered using a jet nebulizer with an oxygen flow rate of 6–8 L/min and a face mask. All patients were managed in accordance with standard supportive care protocols including oxygen therapy, hydration, and monitoring of vital signs.

Outcome Measures
The primary outcome was the change in the Clinical Severity Score (CSS), which included parameters such as respiratory rate, wheezing, use of accessory muscles, and oxygen saturation. Assessments were made at baseline, on day 3, and on day 5.

Secondary outcomes included:

• Duration of hospitalization
• Duration of supplemental oxygen requirement
• Any adverse effects during treatment

Data Analysis
Data were compiled using Microsoft Excel and analyzed using SPSS software version 25.0. Continuous variables were presented as mean ± standard deviation, and categorical variables as frequencies and percentages. Independent t-tests were used for comparison between groups, while repeated measures ANOVA was applied to assess changes in clinical severity scores over time. A p-value of less than 0.05 was considered statistically significant.

A total of 60 infants were enrolled and completed the study, with 30 participants in each group. The baseline demographic and clinical characteristics were comparable between Group A (hypertonic saline) and Group B (normal saline), indicating proper randomization.

Table 1 presents the baseline characteristics, including age, sex distribution, and initial clinical severity score (CSS). The mean age of infants in Group A was 5.4 ± 2.1 months, while in Group B it was 5.2 ± 2.4 months (p=0.74). The baseline CSS was similar between both groups (6.3 ± 1.1 in Group A vs. 6.1 ± 1.2 in Group B; p=0.52), suggesting homogeneity of clinical severity at presentation.

Table 1. Baseline Characteristics of Study Participants

On day 3 of treatment, Group A showed a more marked improvement in CSS (mean 3.7 ± 1.0) compared to Group B (4.5 ± 1.1; p=0.01). By day 5, the improvement was even more significant, with Group A having a mean CSS of 2.1 ± 0.9 compared to 3.3 ± 1.0 in Group B (p<0.001), as shown in Table 2.

Table 2. Clinical Outcomes between Groups on Day 3 and Day 5

The average duration of hospital stay was notably lower in Group A (3.2 ± 0.7 days) compared to Group B (4.4 ± 0.9 days; p=0.002). Similarly, oxygen therapy was required for a shorter duration in Group A (1.6 ± 0.5 days) than in Group B (2.5 ± 0.6 days; p=0.004) (Table 2).

No adverse events related to nebulization were reported in either group during the study period.

The findings of this study support the clinical efficacy of 3% hypertonic saline nebulization in improving outcomes in infants diagnosed with acute bronchiolitis. Infants treated with hypertonic saline demonstrated a significantly greater reduction in clinical severity scores by day 5, along with shorter hospital stays and reduced oxygen requirements compared to those who received normal saline. These results align with previous trials and systematic reviews indicating that hypertonic saline can enhance mucociliary clearance and reduce airway edema, leading to faster clinical improvement (1–3).

The rationale for using hypertonic saline is based on its ability to osmotically draw water into the airway lumen, thin mucus secretions, and facilitate more efficient airway clearance (4,5). In addition, hypertonic saline may reduce airway inflammation and enhance epithelial repair mechanisms, further contributing to clinical improvement (6,7). The observed reduction in hospital stay by over one day in the intervention group has both clinical and economic implications, especially in low-resource settings where hospitalization costs can impose a significant burden on healthcare systems (8,9).

Our findings are consistent with those of Luo et al. who reported faster symptom resolution and shorter hospital stays in infants treated with 3% saline (10). Similarly, Zhang et al., in a Cochrane review involving over 1000 infants, concluded that hypertonic saline nebulization significantly reduced hospital stay by nearly one day and improved overall clinical scores (2). Tal et al. also demonstrated comparable results in their randomized trial where hypertonic saline improved respiratory scores and reduced the length of hospitalization (11).

However, not all studies have shown consistent benefits. For example, a multicenter trial by Ralston et al. failed to find significant improvements in hospital stay duration, possibly due to variability in administration protocols and patient selection criteria (12). Furthermore, a study by Everard et al. suggested that the beneficial effects of hypertonic saline may be more pronounced in infants with moderate rather than severe disease (13). Our study excluded critically ill patients, which may explain the positive response observed in our cohort.

Importantly, none of the infants in our study experienced adverse reactions to nebulized hypertonic saline, which supports the safety profile reported in earlier literature (14,15). This reinforces the feasibility of incorporating hypertonic saline into routine bronchiolitis management, particularly when used alongside standard supportive care.

Limitations of this study include the relatively small sample size and single-center design, which may limit generalizability. Also, objective viral identification was not performed, though clinical diagnosis of bronchiolitis is typically sufficient for management. Future multicenter trials with larger populations and standardized protocols may help resolve existing discrepancies in the literature

In conclusion, our findings strengthen the growing body of evidence advocating the use of 3% hypertonic saline as an effective and safe adjunctive therapy in managing acute bronchiolitis in infants. It offers a practical and cost-effective option to improve clinical outcomes and reduce hospital resource utilization.

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