The Effect of Readmission for Phototherapy on Early Breast Milk Feeding.

OBJECTIVES: To estimate the effect of readmission for inpatient phototherapy on parent-reported exclusive and any breast milk feeding at 2-month well-child visits. METHODS: We performed a retrospective cohort study using electronic health record data. From births at 16 Kaiser Permanente Northern California hospitals (2013-2017), we identified a cohort of infants ≥35 weeks' gestation with outpatient total serum bilirubin levels ranging from 1 mg/dL below to 2.9 mg/dL above the American Academy of Pediatrics phototherapy threshold at <15 days of age. We compared breast milk feeding at 2-month well-child visits among those readmitted and not readmitted to the hospital for phototherapy, adjusting for bilirubin and other confounding variables. RESULTS: Approximately one-quarter (26.5%) of the cohort (n = 7729) were readmitted for phototherapy. Almost half (48.5%) of the infants who were not readmitted for phototherapy received exclusively breast milk at the 2-month visit compared with slightly fewer infants who were readmitted (42.9%). In both groups of infants, most (82.2% not readmitted and 81.2% readmitted) received any breast milk. Readmission for phototherapy was associated with a lower adjusted risk of exclusive breast milk feeding (adjusted risk ratio 0.90; 95% confidence interval [CI], 0.84 to 0.96), corresponding to a marginal absolute reduction in exclusive breast milk feeding of 5.0% (95% CI, -7.9% to -2.1%). It was not associated with a reduction in any breast milk feeding (adjusted risk ratio, 1.00; 95% CI, 0.97 to 1.02). CONCLUSIONS: Infants readmitted for phototherapy were more likely to receive any formula, but no less likely to receive any breast milk at 2-month well-child visits.

The effect of hospital phototherapy on early breastmilk feeding.

BACKGROUND: The effect of phototherapy on breastmilk feeding is unclear. OBJECTIVE: To estimate the effect of inpatient phototherapy on breastmilk feeding at 2-month well-child visits. METHODS: We performed a retrospective cohort study using electronic health record data. From births at 16 Kaiser Permanente Northern California hospitals (2013-2017), we identified a cohort of infants ≥ 35 weeks' gestation with total serum bilirubin levels close to the American Academy of Pediatrics 2004 phototherapy threshold during their birth hospitalisation. We compared self-reported breastmilk feeding at 2-month well-child visits among those who had and had not received birth hospitalisation phototherapy, adjusting for bilirubin levels and other confounding variables. We used multiple imputation (K = 200) to address missing data. RESULTS: Approximately a quarter of infants in the cohort (24.5%) received phototherapy during their birth hospitalisation. At the 2-month visit, exclusive breastmilk feeding was less common (RR 0.91, 95% interval [CI] 0.88, 0.95) among those who received phototherapy (41.3%) than those who did not (45.2%). However, no association remained after adjusting for potential confounders (RR 0.99, 95% CI 0.95, 1.04; average treatment effect on the treated [ATET] -0.2%, 95% CI -2.0%, 1.5%). In contrast, any breastmilk feeding was similar between infants who did (76.8%) and did not get phototherapy (77.9%). After adjusting for confounders, phototherapy had a slightly positive association with any breastmilk feeding at 2 months (RR 1.02, 95% CI 1.00, 1.04). Among infants who received phototherapy, the proportion being fed any breastmilk at the 2-month visit was an estimated 1.6 percentage points higher than it would have been if they had not received phototherapy (ATET 1.6%, 95% CI 0.1%, 3.1%). Multiple imputation results were similar. CONCLUSIONS: Birth hospitalisation phototherapy can be delivered in a way that does not adversely affect breastmilk feeding at 2 months.

Accuracy of international classification of diseases, ninth revision, codes for postpartum hemorrhage among women undergoing cesarean delivery.

BACKGROUND: Determining the accuracy of International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9) codes for postpartum hemorrhage (PPH) is vital for reaching valid conclusions about the epidemiology of PPH. Our primary objectives were to assess the performance characteristics of ICD-9 PPH codes against a reference standard using estimated blood loss (EBL) among a cohort undergoing Cesarean delivery. STUDY DESIGN AND METHODS: We analyzed maternal discharge and EBL data from women who underwent Cesarean delivery at Kaiser Permanente Northern California facilities between 2010 and 2013. We defined PPH as an EBL of at least 1000 mL. In a secondary analysis, ICD-9 performance characteristics were assessed using an EBL of at least 1500 mL to classify severe PPH. RESULTS: We identified 35,614 hospitalizations for Cesarean delivery. Using EBL of at least 1000 mL as the "gold standard," PPH codes had a sensitivity of 27.8%, specificity of 97%, positive predictive value (PPV) of 74.5%, and a negative predictive value (NPV) of 80.9%. The prevalence of a PPH code (9%) was lower than the prevalence using a blood loss of at least 1000 mL (24%). Using a reference standard of EBL of at least 1500 mL, PPH codes had a sensitivity of 61.7%, specificity of 93.8%, PPV of 34.2%, and NPV of 97.9%. CONCLUSION: PPH ICD-9 codes have high specificity, moderately high PPVs and NPVs, and low sensitivity. An EBL of at least 1500 mL as a reference standard has higher sensitivity. Our findings suggest that, for women undergoing Cesarean delivery, quality improvement efforts are needed to enhance PPH ICD-9 coding accuracy in administrative data sets.

Effectiveness of Respiratory Syncytial Virus Immunoprophylaxis in Reducing Bronchiolitis Hospitalizations Among High-Risk Infants.

We sought to determine the real-world effectiveness of respiratory syncytial virus (RSV) immunoprophylaxis in a population-based cohort to inform policy. The study population included infants born during 1996-2008 and enrolled in the Kaiser Permanente Northern California integrated health-care delivery system. During the RSV season (November-March), the date of RSV immunoprophylaxis administration and the following 30 days were defined as RSV immunoprophylaxis protected period(s), and all other days were defined as unprotected period(s). Numbers of bronchiolitis hospitalizations were determined using International Classification of Diseases, Ninth Revision, codes during RSV season. We used a proportional hazards model to estimate risk of bronchiolitis hospitalization when comparing infants' protected period(s) with unprotected period(s). Infants who had ever received RSV immunoprophylaxis had a 32% decreased risk of bronchiolitis hospitalization (adjusted hazard ratio = 0.68, 95% confidence interval: 0.46, 1.00) when protected periods were compared with unprotected periods. Infants with chronic lung disease (CLD) had a 52% decreased risk of bronchiolitis hospitalization (adjusted hazard ratio = 0.48, 95% confidence interval: 0.25, 0.94) when protected periods were compared with unprotected periods. Under the new 2014 American Academy of Pediatrics (AAP) guidelines, 48% of infants eligible for RSV immunoprophylaxis on the basis of AAP guidelines in place at birth would no longer be eligible, but nearly all infants with CLD would remain eligible. RSV immunoprophylaxis is effective in decreasing hospitalization. This association is greatest for infants with CLD, a group still recommended for receipt of RSV immunoprophylaxis under the new AAP guidelines.

Outcomes of Admissions for Preterm Labor.

Objective This study aims to quantitate the incidence of preterm labor (PTL) admissions and determine the frequency and predictors of preterm delivery (PTD) during these admissions. Study Design Retrospective cohort of singleton pregnancies within Kaiser Permanente Northern California, 2001 to 2011. PTL admissions were defined as inpatient encounters > 24 hours with an International Classification of Diseases, 9th Revision code for PTL. Results Total study population was 365,897 with PTL admission rate 11%. PTD occurred in 85% of pregnancies with PTL admission. Delivery occurred within 48 hours of admission in 96% ≥34 weeks, 67% 31 to 33 weeks, and 51.9% <31 weeks. Predictors of delivery during PTL admission included gestational age 34 to 36 weeks (adjusted odds ratio [aOR], 6.90), chorioamnionitis (aOR, 105.58), and preterm rupture of membranes (aOR 19.29). Conclusion We demonstrate a high rate of PTD per PTL admission in a highly integrated health care system. More work is needed to determine optimal practices for hospitalization and treatment of women diagnosed with PTL.

A Quantitative, Risk-Based Approach to the Management of Neonatal Early-Onset Sepsis.

Importance: Current algorithms for management of neonatal early-onset sepsis (EOS) result in medical intervention for large numbers of uninfected infants. We developed multivariable prediction models for estimating the risk of EOS among late preterm and term infants based on objective data available at birth and the newborn's clinical status. Objectives: To examine the effect of neonatal EOS risk prediction models on sepsis evaluations and antibiotic use and assess their safety in a large integrated health care system. Design, Setting, and Participants: The study cohort includes 204 485 infants born at 35 weeks' gestation or later at a Kaiser Permanente Northern California hospital from January 1, 2010, through December 31, 2015. The study compared 3 periods when EOS management was based on (1) national recommended guidelines (baseline period [January 1, 2010, through November 31, 2012]), (2) multivariable estimates of sepsis risk at birth (learning period [December 1, 2012, through June 30, 2014]), and (3) the multivariable risk estimate combined with the infant's clinical condition in the first 24 hours after birth (EOS calculator period [July 1, 2014, through December 31, 2015]). Main Outcomes and Measures: The primary outcome was antibiotic administration in the first 24 hours. Secondary outcomes included blood culture use, antibiotic administration between 24 and 72 hours, clinical outcomes, and readmissions for EOS. Results: The study cohort included 204 485 infants born at 35 weeks' gestation or later: 95 343 in the baseline period (mean [SD] age, 39.4 [1.3] weeks; 46 651 male [51.0%]; 37 007 white, non-Hispanic [38.8%]), 52 881 in the learning period (mean [SD] age, 39.3 [1.3] weeks; 27 067 male [51.2%]; 20 175 white, non-Hispanic [38.2%]), and 56 261 in the EOS calculator period (mean [SD] age, 39.4 [1.3] weeks; 28 575 male [50.8%]; 20 484 white, non-Hispanic [36.4%]). In a comparison of the baseline period with the EOS calculator period, blood culture use decreased from 14.5% to 4.9% (adjusted difference, -7.7%; 95% CI, -13.1% to -2.4%). Empirical antibiotic administration in the first 24 hours decreased from 5.0% to 2.6% (adjusted difference, -1.8; 95% CI, -2.4% to -1.3%). No increase in antibiotic use occurred between 24 and 72 hours after birth; use decreased from 0.5% to 0.4% (adjusted difference, 0.0%; 95% CI, -0.1% to 0.2%). The incidence of culture-confirmed EOS was similar during the 3 periods (0.03% in the baseline period, 0.03% in the learning period, and 0.02% in the EOS calculator period). Readmissions for EOS (within 7 days of birth) were rare in all periods (5.2 per 100 000 births in the baseline period, 1.9 per 100 000 births in the learning period, and 5.3 per 100 000 births in the EOS calculator period) and did not differ statistically (P = .70). Incidence of adverse clinical outcomes, including need for inotropes, mechanical ventilation, meningitis, and death, was unchanged after introduction of the EOS calculator. Conclusions and Relevance: Clinical care algorithms based on individual infant estimates of EOS risk derived from a multivariable risk prediction model reduced the proportion of newborns undergoing laboratory testing and receiving empirical antibiotic treatment without apparent adverse effects.

Persistent recurring wheezing in the fifth year of life after laboratory-confirmed, medically attended respiratory syncytial virus infection in infancy.

BACKGROUND: Respiratory syncytial virus (RSV) infection in infancy is associated with subsequent recurrent wheezing. METHODS: A retrospective cohort study examined children born at ≥32 weeks gestation between 1996-2004. All children were enrolled in an integrated health care delivery system in Northern California and were followed through the fifth year of life. The primary endpoint was recurrent wheezing in the fifth year of life and its association with laboratory-confirmed, medically-attended RSV infection during the first year, prematurity, and supplemental oxygen during birth hospitalization. Other outcomes measured were recurrent wheezing quantified through outpatient visits, inpatient hospital stays, and asthma prescriptions. RESULTS: The study sample included 72,602 children. The rate of recurrent wheezing in the second year was 5.6% and fell to 4.7% by the fifth year. Recurrent wheezing rates varied by risk status: the rate was 12.5% among infants with RSV hospitalization, 8% among infants 32-33 weeks gestation, and 18% in infants with bronchopulmonary dysplasia. In multivariate analyses, increasing severity of respiratory syncytial virus infection was significantly associated with recurrent wheezing in year 5; compared with children without RSV infection in infancy, children who only had an outpatient RSV encounter had an adjusted odds ratio of 1.38 (95% CI,1.03-1.85), while children with a prolonged RSV hospitalization had an adjusted odds ratio of 2.59 (95% CI, 1.49-4.50). CONCLUSIONS: Laboratory-confirmed, medically attended RSV infection, prematurity, and neonatal exposure to supplemental oxygen have independent associations with development of recurrent wheezing in the fifth year of life.

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.

Recurrent wheezing in the third year of life among children born at 32 weeks' gestation or later: relationship to laboratory-confirmed, medically attended infection with respiratory syncytial virus during the first year of life.

OBJECTIVE: To quantify the relationship between recurrent wheezing (RW) in the third year of life and respiratory syncytial virus (RSV) infection, prematurity, and neonatal oxygen exposure. DESIGN: Retrospective cohort study linking inpatient, outpatient, and laboratory databases for cohort assembly and logistic regression analysis. SETTING: Integrated health care delivery system in Northern California. PARTICIPANTS: A total of 71,102 children born from 1996 to 2002 at 32 weeks' gestational age or later who were health plan members for 9 or more months in their first and third years. MAIN EXPOSURES: Laboratory-confirmed, medically attended RSV infection during first year and supplemental oxygen during birth hospitalization. OUTCOME MEASURES: Recurrent wheezing, quantified through outpatient visits, inpatient hospital stays, and asthma prescriptions. RESULTS: The rate of RW in the third year of life was 16.23% among premature infants with RSV and 6.22% among those without RSV. The risk of RW increased among infants who had an RSV outpatient encounter (adjusted odds ratio [AOR], 2.07; 95% CI, 1.61-2.67), uncomplicated RSV hospitalization (AOR, 4.66; 95% CI, 3.55-6.12), or prolonged RSV hospitalization (AOR, 3.42; 95% CI, 2.01-5.82) compared with infants without RSV encounters. Gestational age of 34 to 36 weeks was associated with increased risk of RW (AOR, 1.23; 95% CI 1.07-1.41) compared with 38 to 40 weeks, while a gestational age of 41 weeks or more was protective (AOR, 0.90; 95% CI, 0.81-0.99). Supplemental oxygen exposure was associated with increased risk at all levels. CONCLUSION: Laboratory-confirmed, medically attended RSV infection, prematurity, and exposure to supplemental oxygen during the neonatal period have independent associations with the development of RW in the third year of life.

Respiratory syncytial virus testing during bronchiolitis episodes of care in an integrated health care delivery system: a retrospective cohort study.

BACKGROUND: Bronchiolitis has the highest incidence rate of any lower respiratory infection among infants and children <2 years of age. Respiratory syncytial virus (RSV) is the most common etiology of bronchiolitis. The American Academy of Pediatrics does not recommend routine RSV testing for infants and children with bronchiolitis. The clinical predictors of RSV testing are unknown. OBJECTIVES: The aims of this study were to identify the rates and predictors of RSV testing during bronchiolitis and to explore the relationship between RSV test results and antibiotic treatment among infants and children aged <2 years. METHODS: A retrospective study was conducted of 123,264 infants ≥32 weeks' gestational age (GA) who were born at 1 of 6 Northern California Kaiser Permanente Medical Center Program hospitals between 1996 and 2004. A bronchiolitis episode of care (EOC) was defined as ≥1 medical encounters with a bronchiolitis diagnosis code followed by 14 clear days without a bronchiolitis-related medical encounter. Descriptive statistics were used to report the frequency of tests, and logistic regression was used to assess the effect of hospitalization, chronologic age, gestational age, and season on the frequency of testing for RSV. Rapid direct fluorescent antibody testing was performed during the study. RESULTS: The birth cohort was 51.2% male and 42.7% white, 20.8% Hispanic, 20.3% Asian, 8.4% African American, and 7.9% other. Of 23,748 bronchiolitis EOCs, 4969 (20.9%) had ≥1 test for RSV. Overall, 44.2% of all tests were positive for RSV. Physicians ordered RSV tests in 30.4% and 26.7% of bronchiolitis EOCs for infants born at 32 to 33 and 34 to 36 weeks' GA, respectively, compared with 17.9% of bronchiolitis EOCs for infants born at ≥41 weeks' GA. Bronchiolitis hospitalization, younger chronologic age, prematurity, and RSV season were associated with RSV testing in a multivariate model controlling for other variables, with an adjusted odds ratio (AOR) of 28.55 (95% CI, 24.99-36.62) for hospitalization status; AOR of 6.89 (95% CI, 5.19-9.15) for chronologic age <1 month; AOR of 0.85 (95% CI, 0.76-0.95) for GA >41 weeks; and AOR of 2.48 (95% CI, 2.24-2.74) for RSV season (December-March). Among hospitalized infants who were tested and had a diagnostic code suggesting treatment with antibiotics, use of antibiotics was significantly lower among those with a positive RSV test (63.4%) than those with a negative RSV test (75.5%) (χ(2) test; P < 0.001). CONCLUSIONS: Approximately 20% of these children with bronchiolitis EOCs were tested for RSV; of those tested, about half were positive. In this integrated health care system, hospitalization with bronchiolitis, chronologic age, gestational age <37 weeks, neonatal oxygen exposure, and bronchiolitis EOC during the RSV season were the factors associated with testing for RSV.