Race-Neutral Equations and Pulmonary Function Test Interpretation in Two Pediatric Cohorts.

OBJECTIVE: To investigate the changes in predicted lung function measurements when using race-neutral equations in children, based upon the new Global Lung Initiative (GLI) reference equations, utilizing a race-neutral approach in interpreting spirometry results compared with the 2012 race-specific GLI equations. STUDY DESIGN: We analyzed data from 2 multicenter prospective cohorts comprised of healthy children and children with history of severe (requiring hospitalization) bronchiolitis. Spirometry testing was done at the 6-year physical exam, and 677 tests were analyzed using new GLI Global and 2012 GLI equations. We used multivariable logistic regression, adjusted for age, height, and sex, to examine the association of race with the development of new impairment or increased severity (forced expiratory volume in the first second (FEV1) z-score ≤ -1.645) as per 2022 American Thoracic Society (ATS) guidelines. RESULTS: Compared with the race-specific GLI, the race-neutral equation yielded increases in the median forced expiratory volume in the first second and forced vital capacity (FVC) percent predicted in White children but decreases in these two measures in Black children. The prevalence of obstruction increased in White children by 21%, and the prevalence of possible restriction increased in Black children by 222%. Compared with White race, Black race was associated with increased prevalence of new impairments (aOR 7.59; 95%CI, 3.00-19.67; P < .001) and increased severity (aOR 35.40; 95%CI, 4.70-266.40; P = .001). Results were similar across both cohorts. CONCLUSIONS: As there are no biological justifications for the inclusion of race in spirometry interpretation, use of race-neutral spirometry reference equations led to an increase in both the prevalence and severity of respiratory impairments among Black children.

Disparities in infant hospitalizations in Indigenous and non-Indigenous populations in Quebec, Canada.

BACKGROUND: Infant mortality is higher in Indigenous than non-Indigenous populations, but comparable data on infant morbidity are lacking in Canada. We evaluated disparities in infant morbidities experienced by Indigenous populations in Canada. METHODS: We used linked population-based birth and health administrative data from Quebec, Canada, to compare hospitalization rates, an indicator of severe morbidity, in First Nations, Inuit and non-Indigenous singleton infants (< 1 year) born between 1996 and 2010. RESULTS: Our cohort included 19 770 First Nations, 3930 Inuit and 225 380 non-Indigenous infants. Compared with non-Indigenous infants, all-cause hospitalization rates were higher in First Nations infants (unadjusted risk ratio [RR] 2.05, 95% confidence interval [CI] 1.99-2.11; fully adjusted RR 1.43, 95% CI 1.37-1.50) and in Inuit infants (unadjusted RR 1.96, 95% CI 1.87-2.05; fully adjusted RR 1.37, 95% CI 1.24-1.52). Higher risks of hospitalization (accounting for multiple comparisons) were observed for First Nations infants in 12 of 16 disease categories and for Inuit infants in 7 of 16 disease categories. Maternal characteristics (age, education, marital status, parity, rural residence and Northern residence) partly explained the risk elevations, but maternal chronic illnesses and gestational complications had negligible influence overall. Acute bronchiolitis (risk difference v. non-Indigenous infants, First Nations 37.0 per 1000, Inuit 39.6 per 1000) and pneumonia (risk difference v. non-Indigenous infants, First Nations 41.2 per 1000, Inuit 61.3 per 1000) were the 2 leading causes of excess hospitalizations in Indigenous infants. INTERPRETATION: First Nations and Inuit infants had substantially elevated burdens of hospitalizations as a result of diseases of multiple systems. The findings identify substantial unmet needs in disease prevention and medical care for Indigenous infants.

Trends in lower respiratory tract infection hospitalizations among American Indian/Alaska Native children and the general US child population.

OBJECTIVE: To describe trends in the rate of hospitalization for lower respiratory tract infection (LRTI) among American Indian/Alaska Native (AI/AN) children and the general US population of children aged <5 years. STUDY DESIGN: This was a retrospective analysis of trends and hospitalization rates for LRTI-associated hospitalizations in 1998-2008 among AI/AN children aged <5 years using the Indian Health Service direct/contract inpatient data, and also among the general population of US children aged <5 years using the Nationwide Inpatient Sample. RESULTS: The 2006-2008 LRTI-associated hospitalization rate for AI/AN children aged <5 years (21.8 per 1000/year) was 32% lower than the 1998-1999 rate, and 1.6-fold higher than the general US children rate (13.8 per 1000/year; 95% CI, 12.8-14.8). Higher rates were seen in AI/AN children aged <5 years in the Alaska and the Southwest regions of the United States (41.2 and 28.0 per 1000/year, respectively). In infants, these rates were 136.4 and 82.4 per 1000/year, respectively, exceeding the rate in the general US infant population (37.1 per 1000/year; 95% CI, 34.3-40.0). The greatest disparity in the LRTI-associated hospitalization rate between AI/AN infants and the general US infant population was seen for pneumonia, with a 3-fold higher rate in AI/AN infants (36.2 per 1000/year vs 12.7 per 1000/year; 95% CI, 11.8-13.6). CONCLUSION: The LRTI-associated hospitalization rate is higher in AI/AN children, particularly infants from Alaska and the American Southwest, compared with the general US child population. Closing this gap will require addressing housing and sanitation inequities and ensuring high immunization rates and access to care.

Frequency, duration and predictors of bronchiolitis episodes of care among infants ≥32 weeks gestation in a large integrated healthcare system: a retrospective cohort study.

BACKGROUND: Bronchiolitis is common in the first two years of life and is the most frequent cause of hospitalization in this age group. No previous studies have used an episode-of-care analysis to describe the frequency, duration, and predictors of bronchiolitis episodes of care during the first two years. METHODS: We conducted a retrospective cohort study of 123,264 infants ≥32 weeks gestation born at 6 Northern California Kaiser Permanente hospitals between 1996 and 2002. We used electronic medical records to concatenate hospital, emergency department and outpatient health care encounters for bronchiolitis into discrete episodes of care. We used descriptive statistics to report frequency and duration of bronchiolitis episodes and used logistic regression to assess the effect of gestational age and other clinical and demographic predictors on the outcome of bronchiolitis episodes. RESULTS: Among all infants, the rate of bronchiolitis episodes was 162 per 1000 children during the first 2 years of life; approximately 40% required >1 day of medical attention with a mean duration of 7.0 ± 5.9 days. Prematurity was associated with increased risk of bronchiolitis episodes and longer duration. Bronchiolitis episodes rates per 1000 infants were 246 for 32-33 weeks gestational age, 204 for 34-36 weeks, and 148-178 for >36 weeks. Male gender, African-American and Hispanic race/ethnicity, and parental history of asthma were associated with an increased risk of having a bronchiolitis episode and/or longer duration. CONCLUSIONS: Bronchiolitis episodes of care are frequent during the first two years of life and the duration ranges from 1 to 27 days. Prematurity was associated with more frequent and longer duration of bronchiolitis episodes of care, which may reflect illness severity and/or perceived vulnerability.

Deprivation, ethnicity and prematurity in infant respiratory failure in PICU in the UK.

AIM: To describe the epidemiology of infants admitted to Paediatric Intensive Care (PIC) with acute respiratory failure including bronchiolitis. METHODS: Data from all consecutive admissions from 2004 to 2007 in all 29 designated Paediatric Intensive Care Units (PICUs) in England and Wales were collected. Admission rates, risk-adjusted mortality, length of stay, ventilation status, preterm birth, deprivation and ethnicity were studied. RESULTS: A total of 4641 infants under 1 year of age had an unplanned admission to PIC with acute respiratory failure (ARF), an admission rate of 1.80 per 1000 infants per year. There was a reduced rate of admission with bronchiolitis in South Asian children admitted to PICU, which is not explained by case-mix. Children born preterm had a higher rate of admission and longer stay, but a similar low mortality. Risk-adjusted mortality was higher in South Asian infants and the highest in those with ARF (OR 1.76, 95% CI 1.20-2.57) compared with the rest of the PICU population. CONCLUSION: Acute respiratory failure in infants causes most of the seasonal variation in unplanned admission to intensive care. Socioeconomic deprivation and prematurity are additional risk factors for admission. Fewer South Asian infants are admitted to PICU with a diagnosis of bronchiolitis, but risk-adjusted mortality is higher in South Asian infants overall.

Idiopathic bronchiolitis with features of diffuse panbronchiolitis in an African-American patient with hepatitis C virus infection.

Diffuse panbronchiolitis (DPB) is an idiopathic inflammatory process involving respiratory bronchioles, largely restricted to Japanese people and associated with HLA Bw54. We report a case of idiopathic bronchiolitis with DPB features in an African American with hepatitis C virus infection, correlated with postmortem anatomic findings. The 53-year-old patient presented with shortness of breath and productive cough. Examination revealed hypercapnic respiratory failure. Lung computed tomography showed diffuse centrilobular nodules and branching linear opacities, whereas lung biopsy demonstrated diffuse peribronchiolar fibrosis and chronic inflammation with bronchiolectasis. He died 37 days postadmission. Autopsy revealed numerous bronchiolocentric nodules with bronchiolectasis and sheets of foamy macrophages in alveolar septa and spaces. This is a rare example of idiopathic bronchiolitis with features of DPB in an hepatitis C virus-infected African-American patient. Hepatitis C virus infection is known to be associated with extrahepatic pulmonary manifestations, and DPB may be one of these. Early diagnosis will allow appropriate treatment and may slow the disease progression.

Risks of severity and readmission of Indigenous and non-Indigenous children hospitalised for bronchiolitis.

OBJECTIVE: To describe the characteristics of children admitted to Royal Darwin Hospital with bronchiolitis, and to compare the severity of illness and incidence of subsequent readmission in Indigenous and non-Indigenous children. DESIGN, SETTING AND PARTICIPANTS: Retrospective study of 101 children (aged

Human T-Lymphotropic Virus type 1c subtype proviral loads, chronic lung disease and survival in a prospective cohort of Indigenous Australians.

BACKGROUND: The Human T-Lymphotropic Virus type 1c subtype (HTLV-1c) is highly endemic to central Australia where the most frequent complication of HTLV-1 infection in Indigenous Australians is bronchiectasis. We carried out a prospective study to quantify the prognosis of HTLV-1c infection and chronic lung disease and the risk of death according to the HTLV-1c proviral load (pVL). METHODOLOGY/PRINCIPAL FINDINGS: 840 Indigenous adults (discharge diagnosis of bronchiectasis, 154) were recruited to a hospital-based prospective cohort. Baseline HTLV-1c pVL were determined and the results of chest computed tomography and clinical details reviewed. The odds of an association between HTLV-1 infection and bronchiectasis or bronchitis/bronchiolitis were calculated, and the impact of HTLV-1c pVL on the risk of death was measured. Radiologically defined bronchiectasis and bronchitis/bronchiolitis were significantly more common among HTLV-1-infected subjects (adjusted odds ratio = 2.9; 95% CI, 2.0, 4.3). Median HTLV-1c pVL for subjects with airways inflammation was 16-fold higher than that of asymptomatic subjects. There were 151 deaths during 2,140 person-years of follow-up (maximum follow-up 8.13 years). Mortality rates were higher among subjects with HTLV-1c pVL ≥1000 copies per 105 peripheral blood leukocytes (log-rank χ2 (2df) = 6.63, p = 0.036) compared to those with lower HTLV-1c pVL or uninfected subjects. Excess mortality was largely due to bronchiectasis-related deaths (adjusted HR 4.31; 95% CI, 1.78, 10.42 versus uninfected). CONCLUSION/SIGNIFICANCE: Higher HTLV-1c pVL was strongly associated with radiologically defined airways inflammation and with death due to complications of bronchiectasis. An increased risk of death due to an HTLV-1 associated inflammatory disease has not been demonstrated previously. Our findings indicate that mortality associated with HTLV-1c infection may be higher than has been previously appreciated. Further prospective studies are needed to determine whether these results can be generalized to other HTLV-1 endemic areas.

Predictors of successful telephone follow-up in a multicenter study of infants with severe bronchiolitis.

PURPOSE: To identify the characteristics that predict successful telephone follow-up with parents of infants with severe bronchiolitis. METHODS: We analyzed data from a 17-center, prospective cohort study of infants (age <1 year) hospitalized with bronchiolitis during three consecutive fall/winter seasons. Participant contact information and clinical data were collected during the index hospitalization. Parents were called at 6-month intervals (based on the child's age) after discharge to assess respiratory problems. The primary outcome was age 12-month telephone interview status. Participants were classified as unreachable after 28 days of unsuccessful attempts. RESULTS: 798 of 916 children (87%) completed the age 12-month telephone interview. In unadjusted analyses, factors associated with successful follow-up included: private health insurance, annual household income $60,000 or more, and residing in the Northeast, Midwest, or West. Follow-up was less common among non-Hispanic blacks, Hispanics, and households with 3 or more children. In multivariable analyses, follow-up was more likely among parents of females, and, compared with the South, in the Northeast and Midwest (all P < .05). Compared with non-Hispanic whites, non-Hispanic blacks and Hispanics remained less likely to complete the interview as did households with 3 or more children (all P < .05). CONCLUSION: Sociodemographic and geographic factors predict successful telephone follow-up, even among parents of infants with severe illness.

Risk factors for adverse outcomes of Indigenous infants hospitalized with bronchiolitis.

BACKGROUND: Hospitalized bronchiolitis imposes a significant burden among infants, particularly among Indigenous children. Traditional or known risk factors for severe disease are well described, but there are limited data on risks for prolonged hospitalization and persistent symptoms. Our aims were to determine factors (clinical and microbiological) associated with (i) prolonged length of stay (LOS); (ii) persistent respiratory symptoms at 3 weeks; (iii) bronchiectasis up to ∼24 months post-hospitalisation; and (iv) risk of respiratory readmissions within 6 months. METHODS: Indigenous infants hospitalized with bronchiolitis were enrolled at Royal Darwin Hospital between 2008 and 2013. Standardized forms were used to record clinical data. A nasopharyngeal swab was collected at enrolment to identify respiratory viruses and bacteria. RESULTS: The median age of 232 infants was 5 months (interquartile range 3-9); 65% male. On multivariate regression, our 12 point severity score (including accessory muscle use) was the only factor associated with prolonged LOS but the effect was modest (+3.0 hr per point, 95%CI: 0.7, 5.1, P = 0.01). Presence of cough at 3 weeks increased the odds of bronchiectasis (OR 3.0, 95%CI: 1.1, 7.0, P = 0.03). Factors associated with respiratory readmissions were: previous respiratory hospitalization (OR 2.3, 95%CI: 1.0, 5.4, P = 0.05) and household smoke (OR 2.6, 95%CI: 1.0, 6.3, P = 0.04). CONCLUSION: Increased severity score is associated with prolonged LOS in Indigenous children hospitalized with bronchiolitis. As persistent symptoms at 3 weeks post-hospitalization are associated with future diagnosis of bronchiectasis, optimising clinical care beyond hospitalization is needed to improve long-term respiratory outcomes for infants at risk of respiratory disease. Pediatr Pulmonol. 2016;51:613-623. © 2015 Wiley Periodicals, Inc.

Lower respiratory tract infections among american Indian and Alaska Native children and the general population of U.S. Children.

BACKGROUND AND OBJECTIVE: Lower respiratory tract infections (LRTIs) cause substantial childhood morbidity. This study characterizes and compares LRTI-associated morbidity among American Indian/Alaska Native (AI/AN) children and the general population of U.S. children. METHODS: Hospitalization and outpatient records with a diagnosis indicating LRTIs were evaluated for children aged younger than 5 years during 1990-2001. RESULTS: For 1999-2001, the LRTI-associated hospitalization rate was significantly higher for AI/AN children than for U.S. children (116.1 versus 63.2/1000, respectively), with the disparity being greater for infants than for 1- to 4-year-old children. Also the rate of LRTI-associated outpatient visits among AI/AN infants was higher than that for all U.S. infants (737.7 versus 207.2/1000, respectively). LRTI hospitalization and outpatient visit rates were highest in the Alaska and Southwest Indian Health Service regions. During 1990-2001, the LRTI hospitalization rate among AI/AN infants in the Alaska region and among the general U.S. infant population increased. Bronchiolitis-associated hospitalization rates increased for AI/AN and U.S. infants, whereas the pneumonia-associated hospitalization rate decreased among AI/AN infants and remained stable among U.S. infants. CONCLUSIONS: LRTIs continue to be an important cause of morbidity in children, especially among AI/AN infants in the Alaska and Southwest regions. Strategies to reduce LRTI hospitalizations and outpatient visits are warranted for all infants, but the greatest potential impact would be among AI/AN infants.

Diffuse panbronchiolitis in a Hispanic man with travel history to Japan.

Diffuse panbronchiolitis is a chronic airflow disorder of obscure origin, which has been reported infrequently outside of Japan and never with any long-term follow-up. We report such a case in a Hispanic man. Furthermore, this patient had an extensive travel history to the Far East, including Japan. This case raises the possibility of a poorly transmissible infectious agent responsible for the disease.

Hospitalization of Jewish and Bedouin infants in southern Israel for bronchiolitis caused by respiratory syncytial virus.

We conducted a prospective study to determine the clinical picture and impact of respiratory syncytial virus (RSV) on hospitalization for acute bronchiolitis of pediatric patients less than 2 years of age belonging to two different ethnic groups in Southern Israel: Jews and Bedouins. All patients younger than 2 years of age hospitalized for bronchiolitis during a typical RSV season were enrolled. During the study period 120 patients with bronchiolitis were hospitalized, and 83 (69%) were RSV-positive. Their age ranged from 20 days to 9 months. Fifty-five percent of all patients with RSV bronchiolitis were < or = 3 months old and 92% were < or = 6 months old. Patients with RSV bronchiolitis represented 18% of all hospitalized infants < or = 9 months old and 35% of all hospitalizations for respiratory problems of infants < or = 9 months old. The yearly incidence of hospitalization for RSV bronchiolitis was 5.4/1000 live births for Jews and 18/1000 live births for Bedouins. The total number of hospitalization days calculated for 1000 births was 32.1 for the Jews and 86.7 for the Bedouins. RSV has a serious impact on infant morbidity in Southern Israel.

Bronchiolitis-associated hospitalizations among American Indian and Alaska Native children.

BACKGROUND: Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract illness among infants and young children. Respiratory system diseases account for a large proportion of hospitalizations in American Indian and Alaska Native (AI/AN) children; however, aggregate estimates of RSV-associated hospitalizations among AI/AN children have not been made. METHODS: We used Indian Health Service hospitalization data from 1990 through 1995 to describe hospitalizations associated with bronchiolitis, the most characteristic clinical manifestation of RSV infection, among AI/AN children <5 years old. RESULTS: The overall bronchiolitis-associated hospitalization rate among AI/AN infants < 1 year old was considerably higher (61.8 per 1,000) than the 1995 estimated bronchiolitis hospitalization rate among all US infants (34.2 per 1,000). Hospitalization rates were higher among male infants (72.2 per 1,000) than among females infants (51.1 per 1,000). The highest infant hospitalization rate was noted in the Navajo Area (96.3 per 1,000). Hospitalizations peaked annually in January or February, consistent with national peaks for RSV detection. Bronchiolitis hospitalizations accounted for an increasing proportion of hospitalizations for lower respiratory tract illnesses. CONCLUSIONS: Bronchiolitis-associated hospitalization rates are substantially greater for AI/AN infants than those for all US infants. This difference may reflect an increased likelihood of severe RSV-associated disease or a decreased threshold for hospitalization among AI/AN infants with bronchiolitis compared with all US infants. AI/AN children would receive considerable benefit from lower respiratory tract illness prevention programs, including an RSV vaccine, if and when one becomes available.

Asthma and bronchiolitis hospitalizations among American Indian children.

OBJECTIVE: To compare asthma and bronchiolitis hospitalization rates in American Indian and Alaskan native (AI/AN) children and all children in Washington State. METHODS: A retrospective data analysis using Washington State hospitalization data for 1987 through 1996. Patients were included if asthma or bronchiolitis was the first-listed diagnosis. American Indian and Alaskan native children were identified by linking state hospitalization data with Indian Health Service enrollment data. RESULTS: Similar rates of asthma hospitalization were found for AI/AN children older than 1 year compared with all children. In AI/AN children younger than 1 year, hospitalization rates for asthma (528 per 100,000 population; 95% confidence interval [CI], 346-761) and bronchiolitis (2954 per 100,000 population; 95% CI, 2501-3456) were 2 to 3 times higher than the rates in all children (232 per 100,000 population [95% CI, 215-251] and 1190 per 100,000 population [95% CI, 1149-1232], respectively). Hospitalization rates for asthma and bronchiolitis increased 50% between 1987 and 1996 for all children younger than 1 year and almost doubled for AI/AN children younger than 1 year. CONCLUSIONS: American Indian and Alaskan native children have significantly higher rates of hospitalization for wheezing illnesses during the first year of life compared with children of other age groups and races. Furthermore, the disparities in rates have increased significantly over time. Future public health measures directed at managing asthma and bronchiolitis should target AI/AN infants.

Bronchiolitis-associated outpatient visits and hospitalizations among American Indian and Alaska Native children--United States, 1990-2000.

Respiratory syncytial virus (RSV) is the most common cause of lower respiratory tract infection (LRTI) in young children worldwide. Approximately half of all LRTI-associated hospitalizations are caused by bronchiolitis, with RSV accounting for 50%-80% of all bronchiolitis cases. Bronchiolitis is an infection of the bronchial and bronchiolar epithelial cells, with subsequent inflammation and edema resulting in airway obstruction. This process manifests clinically as cough, wheezing, tachypnea, and respiratory distress. Because of the association between bronchiolitis and RSV infection, bronchiolitis is a good indicator of RSV disease; therefore, prevention strategies for RSV should reduce the rate of bronchiolitis. Rates of bronchiolitis-associated hospitalization for American Indian/Alaska Native (AI/AN) children are approximately twice that for the general population of U.S. children. This report describes the first estimate of rates of outpatient bronchiolitis-associated visits and updates rates of bronchiolitis-associated hospitalizations in these populations. Rates of bronchiolitis-associated outpatient visits and hospitalizations were higher for AI/AN children than for other U.S. children, and hospitalization rates for both groups increased during 1990-2000. This report underscores the high burden of bronchiolitis and the need for effective prevention programs for AI/AN communities.

Diffuse panbronchiolitis.

Diffuse panbronchiolitis is a type of chronic bronchiolitis associated with chronic sinusitis and infection of the lower respiratory tract. The cause of this disease is unknown, and it is being seen with increasing prevalence among the Japanese population. This article discusses treatment in light of recent studies.

Diffuse panbronchiolitis in a Caucasian man in Canada.

Diffuse panbronchiolitis (DPB) is a rare, chronic bronchiolar disease in non-Asian populations and is therefore commonly overlooked in Western countries. It usually affects nonsmokers and manifests as persistent air flow obstruction, chronic cough and interstitial nodular opacities. Untreated, the prognosis is poor. In this report the authors describe a Caucasian man of Canadian descent who presented with progressive clinical and lung function impairment despite three years of bronchodilator and corticosteroid treatment with presumed asthma. His chest computed tomography scan showed diffuse centrilobular opacities. Lung biopsy revealed chronic bronchiolitis characterized by infiltration of lymphocytes, plasma cells and foam cells in respiratory and terminal bronchioles, compatible with a diagnosis of DPB. After two months of therapy with clarithromycin, the patient had already shown improvement. Physicians should be aware that DPB may occur in Western countries, and that DPB should be considered in the differential diagnosis of patients with persistent air flow obstruction and nodular shadows on chest radiograms.

Management of severe bronchiolitis: indications for ventilator support.

AIM: Bronchiolitis is a common respiratory illness in children. We reviewed our experience of children under one year presenting to an intensive care unit with a clinical diagnosis of bronchiolitis in order to determine if ethnicity, prematurity, arterial carbon dioxide tension or nasopharyngeal aspirates positive for respiratory syncytial virus were related to the need for ventilator assistance. METHOD: A review of the charts of all infants with bronchiolitis admitted to the paediatric intensive care unit from December 1991 to February 1994 was undertaken. RESULTS: There were 94 infants. Ventilator assistance was given to 24 children--nine children had nasopharyngeal continuous positive airway pressure and 15 children required intermittent positive pressure ventilation. There was no difference in ethnic mix between the respiratory support group (Maori 45%, Pacific Islands 30%, other 25%) and those children managed conservatively (Maori 40%, Pacific Islands 36%, other 24%). Fifteen of the 24 infants who needed ventilator support were born prematurely. The mean (corrected) age of infants who required respiratory support was 1.79 (SD2.98) months compared to 3.32 (SD2.58) months for those infants who did not (p < 0.01). We were able to match 19 of the 24 infants who required ventilator support by age, sex and ethnicity with a nonventilated child. There was no significant difference in admission PaCO2 between groups (7.7 SD 1.5 vs 8.1 SD 1.5 kPa) or highest PaCO2 in the first 24 hours for nonventilated children and preintubation PaCO2 in ventilated children (8.6 SD1.3 vs 8.9 SD 1.9kPa). Nasopharyngeal aspirates were positive for respiratory syncytial virus in 39 patients. Respiratory support was required for 13 children who had positive RSV aspirates and for nine children who were not RSV positive (NS). CONCLUSION: Infants with bronchiolitis that were premature were not likely to need respiratory support. Ethnicity, arterial PaCO2 and positivity for RSV were not related to the need for ventilator assistance.