Table 3.
Association between In Utero Exposure to Maternal Smoking and Bronchiolitis Course∗
| Characteristic | No (n = 1863) | Yes (n = 334) | P |
|---|---|---|---|
| History and findings of physical examination | |||
| Presence of apnea (chart) | 7 | 9 | .07 |
| Respiratory rate, breaths per min, median (IQR) | 48 (40–60) | 48 (38–60) | .78 |
| Retractions, % | .01 | ||
| None | 22 | 22 | |
| Mild | 43 | 38 | |
| Moderate | 25 | 23 | |
| Severe | 4 | 5 | |
| Missing | 6 | 11 | |
| Air entry, % | .86 | ||
| Normal | 35 | 36 | |
| Mild | 34 | 31 | |
| Moderate | 13 | 14 | |
| Severe | 2 | 2 | |
| Missing | 15 | 16 | |
| RDSS, median (IQR) | 4 (3–6) | 4 (3–6) | .72 |
| Oxygen saturation by pulse oximeter or ABG, % | .03 | ||
| <90 | 12 | 12 | |
| 90–93.9 | 18 | 12 | |
| ≥94 | 71 | 77 | |
| Infectious etiology | |||
| RSV/HRV status, % | .003 | ||
| RSV alone | 50 | 42 | |
| HRV alone | 7 | 11 | |
| RSV + HRV | 12 | 16 | |
| RSV + any other non-HRV pathogen | 10 | 13 | |
| HRV + any other non-RSV pathogen | 5 | 3 | |
| Neither RSV nor HRV | 16 | 15 | |
| Resource utilization | |||
| High flow oxygen, % | 8 | 11 | .16 |
| CPAP, % | 5 | 3 | .30 |
| Intubation, % | 4 | 8 | .006 |
| ICU stay, % | 17 | 23 | .008 |
| Hospital length of stay, % | .10 | ||
| <3 days | 56 | 52 | |
| ≥3 days | 44 | 49 |
IQR indicates interquartile range; ABG, arterial blood gas; RDSS, respiratory distress severity score; CPAP, continuous positive airway pressure; ICU, intensive care unit; RSV, respiratory syncytial virus; and HRV, human rhinovirus.
∗
Slight discrepancies in row totals are the result of missing data.