Hemodynamic management of congenital diaphragmatic hernia: the role of targeted neonatal echocardiography

Congenital diaphragmatic hernia (CDH) is a major congenital anomaly, resulting from the herniation of abdominal contents into the thoracic cavity, thereby impeding the proper development of the lungs and pulmonary vasculature. CDH severity correlates with a spectrum of pulmonary hypoplasia, pulmonary hypertension (PHT), and cardiac dysfunction, constituting the pathophysiological triad of this complex condition. The accurate diagnosis and effective management of PHT and cardiac dysfunction is pivotal to optimizing patient outcomes. Targeted neonatal echocardiography is instrumental in delivering real-time data crucial for the bespoke, pathophysiology-targeted hemodynamic management of CDH-associated PHT.

COVID-19 Pandemic-Related Changes in Rates of Neonatal Abstinence Syndrome

This cross-sectional study examines COVID-19 pandemic–related changes in rates of neonatal abstinence syndrome (NAS) and whether infants in urban or rural areas and those with low socioeconomic status were disproportionately affected.

The impact of a care bundle with an emphasis on hemodynamic assessment on the short-term outcomes in neonates with congenital diaphragmatic hernia

OBJECTIVE

To evaluate the short-term outcomes of implementing a care bundle emphasizing frequent hemodynamic assessments by echocardiography in neonates with congenital diaphragmatic hernia (CDH).

STUDY DESIGN

This was a retrospective cohort study of infants with CDH admitted to a quaternary perinatal unit from January 2013 to March 2021. The primary composite outcome was defined as mortality or use of extracorporeal membrane oxygenation or need for respiratory support at discharge.

RESULTS

We identified 37 and 20 CDH infants in Epoch I and II, respectively. More patch repairs (50% vs. 21.9%, p = 0.035) and echocardiograms (6[4-8] vs. 1[0-5], p = 0.003) were performed in Epoch II. While there were no differences in the primary outcome, there was a reduction in mortality in Epoch II (0% vs. 27%, p = 0.01).

CONCLUSION

With the implementation of a CDH care bundle with an emphasis on hemodynamic assessment, we demonstrated a significant reduction in mortality.

Should we "eliminate" PDA shunt in preterm infants? A narrative review

The patent ductus arteriosus frequently poses a significant morbidity in preterm infants, subjecting their immature pulmonary vascular bed to substantial volume overload. This, in turn, results in concurrent hypoperfusion to post-ductal organs, and subsequently alters cerebral blood flow. In addition, treatment has not demonstrated definitive improvements in patient outcomes. Currently, the optimal approach remains a subject of considerable debate with ongoing research controversy regarding the best approach. This article provides a comprehensive review of existing literature.

Maternal-fetal-neonatal microbiome and outcomes associated with prematurity

Our understanding of the premature gut microbiome has increased rapidly in recent years. However, to advance this important topic we must further explore various aspects of the maternal microbiome, neonatal microbiota, and the opportunities for microbiome modulation. We invite authors to contribute research and clinical papers to the Collection "Maternal-fetal-neonatal microbiome and outcomes associated with prematurity".

Antibiotic use in Canadian neonatal intensive care units: a national survey for developing antimicrobial stewardship targets

A survey was conducted among Canadian tertiary neonatal intensive care units. Of the 27 sites who responded, 9 did not have any form of antimicrobial stewardship, and 11 used vancomycin for empirical coverage in late-onset-sepsis evaluations. We detected significant variations in the diagnostic criteria for urinary tract infection and ventilator-associated pneumonia.

Fluid overload in newborns undergoing abdominal surgery: a retrospective study

BACKGROUND

Fluid management in newborns undergoing surgery can be challenging due to difficulties in accurately assessing volume status in context of high fluid needs perioperatively and postoperative third-space fluid loss. Fluid overload can be associated with an increase in neonatal morbidity and mortality.

OBJECTIVE

Our objective was to determine the burden of fluid overload and to evaluate their associations with adverse effects among infants undergoing abdominal surgery at a tertiary perinatal center.

METHODS

Patients from our Neonatal Intensive Care Unit who underwent abdominal surgery from January 2017 to June 2019 were included in this retrospective cohort study. Fluid balance was assessed based on the maximum percentage change in body weight at 3- and 7-postoperative days.

RESULTS

Sixty infants were included, with a median [interquartile range] gestational age (GA) of 29 [25-36] weeks and birth weight of 1240 [721-2871] grams. The median daily actual fluid intake was significantly higher than the prescribed fluid intake in the first 7 postoperative days (163 vs. 145 mL/kg, p < .01). The median maximum change of body weight by postoperative days 3 and 7 were 6% [3-13] and 11% [5-17], respectively. A 1% increase in weight within the first 3 postoperative days was associated with a 0.6-day increase for invasive ventilatory support (p = .012). The correlation was still significant after adjusting for GA (p = .033).

CONCLUSION

Fluid overload within the first 3 postoperative days was associated with an increase in ventilator support among infants. Careful attention to fluid management may affect the optimization of outcomes for newborns undergoing abdominal surgery.

Long-Term Neurodevelopmental Impairment among Very Preterm Infants with Sepsis, Meningitis, and Intraventricular Hemorrhage

INTRODUCTION

Sepsis and intraventricular hemorrhage (IVH) are associated with poorer long-term neurodevelopmental outcomes in very preterm infants (VPIs), but less is known about the long-term effect of meningitis and the combined impact of both meningitis and IVH. Our objective was to examine the long-term neurodevelopmental outcomes of VPIs with late onset sepsis and meningitis, with and without IVH, in Canada.

METHODS

We conducted a retrospective cohort study of all infants <29 weeks GA who were admitted to 26 tertiary-level neonatal intensive care units in the Canadian Neonatal Network (CNN) and Canadian Neonatal Follow-Up Network (CNFUN) databases, from January 1, 2010, to December 31, 2016.

RESULTS

Of the 6,322 infants in the cohort, 4,575 had no infection, 1,590 had late onset culture-positive bloodstream infection (CPBSI) only, and 157 had late onset meningitis. There was a significant (p < 0.05) trend of increasing rates of significant neurodevelopmental delay (sNDI) when comparing infants with no infection (sNDI rate 15.0%), late onset CPBSI (sNDI rate 22.9%), and late onset meningitis (sNDI rate 32.0%), even after adjustment for infant characteristics. Similar trends were observed for neurodevelopmental impairment, cerebral palsy, and individual Bayley-III scores <85 for cognitive, language, and motor development. There was an additive effect of IVH in all infant categories, but there was no multiplicative effect between IVH and late onset meningitis.

CONCLUSION

There was an increasing trend of adverse neurodevelopmental outcomes when infants with no infection, late onset CPBSI and late onset meningitis are compared. IVH had an additive effect.

Blood culture collection practices in NICU; A national survey

Background

Sepsis is the leading cause of mortality and morbidity in neonates. Blood cultures are the gold standard in diagnosing neonatal sepsis; however, there are currently no consensus guidelines for blood culture collection in neonates and significant practice variation exists in Neonatal Intensive Care Units (NICUs) globally.

Objective

To examine current practices in obtaining blood cultures in the evaluation of neonatal sepsis in NICUs across Canada.

Methods

A nine-item electronic survey was sent to each of the 29 level-3 NICUs in Canada, which are equipped to provide highly specialized care for newborns.

Results

Responses were received from 90% (26/29) of sites. Sixty-five percent (17/26) of sites have blood culture collection guidelines for the investigation of neonatal sepsis. Forty-eight percent (12/25) of sites routinely target 1.0 mL per culture bottle. In late-onset sepsis (LOS), 58% (15/26) of sites process one aerobic culture bottle, whereas four sites routinely add anaerobic culture bottles. In early-onset sepsis (EOS) in very low birth weight infants (BW <1.5 kg), 73% (19/26) of sites use umbilical cord blood, and 72% (18/25) use peripheral venipuncture. Two sites routinely collect cord blood for culture in EOS. Only one site applies the concept of differential time-to-positivity to diagnose central-line-associated bloodstream infection.

Conclusions

There is significant practice variation in methods used to obtain blood cultures in level-3 NICUs across Canada. Standardization of blood culture collection practices can provide reliable estimates of the true incidence of neonatal sepsis and help to develop appropriate antimicrobial stewardship strategies.

Targeted neonatal echocardiography for patent ductus arteriosus in neonates reduces the surgical ligation rate without affecting healthcare outcomes

BACKGROUND

Surgical ligation of patent ductus arteriosus (PDA) can be associated with long-term morbidity and adverse outcomes in neonates. Targeted neonatal echocardiography (TNE) has been increasingly used to improve the hemodynamic management. We aimed to evaluate the preoperative assessment impacts of the hemodynamic significance of PDA using TNE on PDA ligation rates and neonatal outcomes.

METHODS

This observational study included preterm infants who underwent PDA ligation during two epochs (Epoch I: January 2013 to December 2014; Epoch II: January 2015 to June 2016). During Epoch II, a comprehensive TNE assessment was performed preoperatively to evaluate the hemodynamic significance of PDA. Primary outcome was the incidence of PDA ligation. Secondary outcomes included the incidence of postoperative cardiorespiratory instabilities, individual morbidities, and the composite outcome of death.

RESULTS

A total of 69 neonates underwent PDA ligation. No difference in baseline demographics was found between the epochs. The incidence of PDA ligation in very low birth weight (VLBW) infants was lower during Epoch II than Epoch I [7.5% vs. 14.6%, rate ratio =0.51 (95% confidence interval =0.30-0.88)]. No differences were observed between epochs in the proportion of VLBW infants who developed post-operative hypotension or oxygenation failure. The composite outcome of death or major morbidity did not significantly differ between Epoch I and Epoch II (91.1% vs. 94.1%, P=1.000).

CONCLUSIONS

Incorporating TNE into a standardized hemodynamic assessment program, we demonstrated a 49% reduction in PDA ligation rate without any increase in postoperative cardiopulmonary instability or short-term neonatal morbidities in a cohort of VLBW infants.

Effectiveness of a neonatal intensive care unit-specific antimicrobial stewardship program: A ten-year review

OBJECTIVE

To evaluate the change in consumption of specific antibiotics in a neonatal intensive care unit after the implementation of an antimicrobial stewardship program (ASP).

DESIGN

Retrospective cohort study between January 1, 2010, and December 31,2019.

SETTING

The neonatal intensive care unit at British Columbia Women's Hospital (Vancouver Canada), a tertiary-care center.

PATIENTS

Admitted neonates prescribed antibiotics.

METHODS

We implemented an ASP with an early implementation phase starting in January 2014 (period 2) and a later phase starting in January 2017 (period 3). Patient demographics were collected, including birth weight, gestational age, history of necrotizing enterocolitis (NEC), and surgical operations from existing databases. Interrupted time-series analysis was used, and comparison of antibiotic days of therapy (DOT) averages were conducted across the preimplementation period (period 1), period 2, and period 3 regarding total patients and subgroups.

RESULTS

We identified 4,512 infants. There was a significant decrease in DOT from 472 (95% confidence interval [CI], 431-517) in period 1 to 405 (95% CI, 367-446) in period 2 to 313 (95% CI, 280-350) in period 3. We detected a significant decrease in the use of ampicillin, aminoglycosides, cloxacillin, and linezolid but not in vancomycin or cefotaxime. Subgroup analyses of infants <1,500 g and those without NEC or surgery showed decreases in the use of cloxacillin, aminoglycosides, and linezolid.

CONCLUSIONS

The implementation of an ASP was associated with a significant decrease in the overall DOT and use of certain antibiotics. This study presents important targets for ongoing ASP work.

Left ventricular dysfunction in the immediate post-natal period

BACKGROUND

Our objective was to examine the clinical presentation, echocardiographic findings, and outcomes of newborns presenting with left ventricle (LV) dysfunction in the first 48 hours of life without perinatal asphyxia or structural heart disease. We hypothesize that LV dysfunction may occur due to maladaptation to extrauterine life.

METHODS

This is a retrospective cohort analysis including infants born in a quaternary perinatal centre. Late preterm and term neonates who were diagnosed with left ventricular dysfunction at less than 48 hours of life were identified using an echocardiography clinical laboratory's database and extracorporeal life support database. LV dysfunction was defined as m-mode fractional shortening (FS) <28% or ejection fraction (EF) <50% on echocardiography or reduced function reported by a cardiologist. Data extracted included patient & maternal demographics, echocardiogram parameters, clinical status, and medications. The primary outcome measure was time to recovery of LV function based on echocardiography.

RESULTS

Of the 69 patients identified, 19 patients were included in the final analysis. The mean gestational age was 38 weeks. Thirteen (68%) infants did not have an underlying cause identified despite extensive work-up. Four (21%) infants had exposure to maternal illicit drug use during pregnancy. Three infants died, and all infants without identifiable etiologies had recovery of LV function within 14 days of life.

CONCLUSIONS

LV dysfunction can occur during the abrupt transition from fetal to neonatal circulation and can be associated with maternal illicit drug use.

Impact of Perinatal Exposure to SARS-CoV-2 Infection on Early Health Outcomes among Infants Born from 2020 to 2021 in British Columbia, Canada

Background

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has impacted healthcare services and outcomes. We aimed to investigate healthcare resource utilization and early health outcomes of infants born to mothers with perinatal SARS-CoV-2 infection.

Methods

The study included all infants born alive between February 1, 2020, and April 30, 2021, in British Columbia. We used linked provincial population-based databases including data on COVID-19 testing, birth, and health information for up to one year from birth. Perinatal COVID-19 exposure for infants was defined being born to mothers with a positive test for SARS-CoV-2 infection during pregnancy or at delivery. Cases of COVID-19-exposed infants were matched with up to four non-exposed infants by birth month, sex, birthplace, and gestational age in weeks. Outcomes included hospitalizations, emergency department visits, and in-/outpatient diagnoses. Outcomes were compared between groups using conditional logistic regression and linear mixed effects models including effect modification by maternal residence.

Results

Among 52,711 live births, 484 infants had perinatal exposure to SARS-CoV-2, an incidence rate of 9.18 per 1000 live births. Exposed infants (54.6% male) had a mean gestational age of 38.5 weeks, and 99% were born in hospital. Proportions of infants requiring at least one hospitalization (8.1% vs. 5.1%) and at least one emergency department visit (16.9% vs. 12.9%) were higher among the exposed vs. unexposed infants, respectively. Among infants from the urban area, those with exposure were more likely to have respiratory infectious diseases (odds ratio: 1.74; 95% confidence intervals: 1.07, 2.84), compared with those without exposure. Interpretation. In our cohort, infants born to mothers with SARS-CoV-2 infection have increased healthcare demands in their early infancy, which warrants further investigation.

Factors Associated with Umbilical Venous Catheter Malposition in Newborns: A Tertiary Center Experience

OBJECTIVE

Umbilical venous catheters (UVC) are widely used in neonatal intensive care (NICU). Noncentral catheter position is known to be associated with multiple adverse complications; however, risk factors for catheter malposition are unclear. This work aimed to identify clinical risk factors and complications associated with UVC malposition in neonates admitted in an NICU.

STUDY DESIGN

A retrospective chart review was performed of inborn babies admitted to BC Women's Hospital NICU with UVC inserted in their first 7 days between July 2016 and June 2018. Infant and maternal demographic, radiograph, UVC-related data, and complications were reviewed.

RESULTS

A total of 257 infants had UVC placed; 158 (61%) and 99 (39%) were in central and noncentral positions after initial placement, respectively. Of initially central-placed UVCs, a further 35 (22%) were pulled back or migrated to malposition on follow-up X-ray. Multivariable logistic regression analysis revealed the use of larger UV (5 Fr) catheter (odds ratio [OR]: 2.5, 95% confidence interval [CI]: 1.1-5.6, p = 0.026) and escalation of respiratory support mode (OR: 1.7, 95% CI: 1.0-2.8, p = 0.049) as significant predictors of catheter malposition.

CONCLUSION

Noncentral UVC position as well as migration were common after initial placement in this cohort. The use of larger size UV catheters and increasingly invasive respiratory support were risk factors associated with higher incidence of UVC malposition. Ongoing surveillance of UVC position is thus recommended.

KEY POINTS

· More than one-third of UV catheters were not in central position after the initial placement.. · Large size UV catheters and increasingly invasive respiratory support were risk factors for UV malposition.. · High incidence of UVC migration was found after initial central placement, warranting surveillance..

Acute kidney injury among preterm infants receiving nonsteroidal anti-inflammatory drugs: A pilot study

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs) are a frequently prescribed class of medications in the neonatal intensive care unit (NICU). We aimed to reveal acute kidney injury (AKI) epidemiology in NSAID-exposed premature infants admitted to the NICU using a standardized definition and determine the percentage of NSAID-exposed patients with adequate serum creatinine (SCr) monitoring.

METHODS

This retrospective study compared infants born at ≤34 weeks gestational age who received NSAID for intraventricular hemorrhage prophylaxis (prophylaxis group) or symptomatic treatment for patent ductus arteriosus (PDA; treatment group) between January and December 2014 at a tertiary NICU. All available SCr and 12-h urine output (UO) values were recorded from admission until day seven post-NSAID exposure. AKI incidence was determined using the neonatal modified Kidney Disease Improving Global Outcomes classification, defined as an increase in SCr (i.e., 1.5 fold rise from previous SCr measurement within seven days or 26.5 mmol/L increase within 48 h) or UO < 1 mL/kg/hour, excluding the first 24 h of life.

RESULTS

We identified 70 eligible subjects; 32 received prophylactic NSAIDs, and 38 received indomethacin or ibuprofen for treating symptomatic PDA. AKI incidence for the entire cohort was 23% (16/70). The prophylaxis group had a significantly lower AKI rate than the treatment group (9% vs. 34%; p = 0.014). The treatment group had a higher proportion of infants with adequate SCr monitoring during NSAID treatment than the prophylaxis group (87% vs. 13%, p < 0.001).

CONCLUSION

NSAID-associated AKI occurred in approximately one-quarter of premature infants overall, and the AKI incidence was higher in infants treated with NSAIDs for the symptomatic treatment of PDA than in those receiving prophylactic treatment during the first day of life. Standardized protocols for monitoring daily SCr and UO after exposure should be implemented for all neonates with NSAID exposure to improve early AKI recognition and management.

Antimicrobial utilization in very-low-birth-weight infants: association with probiotic use

OBJECTIVE

To examine the association between probiotic use and antimicrobial utilization.

STUDY DESIGN

We retrospectively evaluated very-low-birth-weight (VLBW) infants admitted to tertiary neonatal intensive care units in Canada between 2014 and 2019. Our outcome was antimicrobial utilization rate (AUR) defined as number of days of antimicrobial exposure per 1000 patient-days.

RESULT

Of 16,223 eligible infants, 7279 (45%) received probiotics. Probiotic use rate increased from 10% in 2014 to 68% in 2019. The AUR was significantly lower in infants who received probiotics vs those who did not (107 vs 129 per 1000 patient-days, aRR = 0.89, 95% CI [0.81, 0.98]). Among 13,305 infants without culture-proven sepsis or necrotizing enterocolitis ≥Stage 2, 5931 (45%) received probiotics. Median AUR was significantly lower in the probiotic vs the no-probiotic group (78 vs 97 per 1000 patient-days, aRR = 0.85, 95% CI [0.74, 0.97]).

CONCLUSION

Probiotic use was associated with a significant reduction in AUR among VLBW infants.

Antenatal corticosteroid administration and attention-deficit/hyperactivity disorder in childhood: a regression discontinuity study

Background:

Antenatal corticosteroids reduce respiratory morbidity in preterm infants, but their use during late preterm gestation (34–36 weeks) is limited because their safety for longer-term child neurodevelopment is unclear. We sought to determine if fetuses with higher probability of exposure to antenatal corticosteroids had increased rates of prescriptions for attention-deficit/hyperactivity disorder (ADHD) medication in childhood, using a quasiexperimental design that better controls for confounding than existing observational studies.

Methods:

We identified 16 358 children whose birthing parents were admitted for delivery between 31 + 0 (31 weeks, 0 days) and 36 + 6 weeks’ gestation in 2000–2013, using a perinatal data registry from British Columbia, Canada, and linked their records with population-based child ADHD medication data (2000–2018). We used a regression discontinuity design to capitalize on the fact that pregnancies presenting for delivery immediately before and immediately after the clinical cut-off for antenatal corticosteroid administration of 34 + 0 weeks’ gestation have very different levels of exposure to corticosteroids, but are otherwise similar with respect to confounders.

Results:

Over a median follow-up period of 9 years, 892 (5.5%) children had 1 or more dispensations of ADHD medication. Children whose birthing parents were admitted for delivery just before the corticosteroid clinical cut-off of 34 + 0 weeks’ gestation did not appear to be more likely to be prescribed ADHD medication than those admitted just after the cut-off (rate ratio 1.1, 95% confidence interval [CI] 0.8 to 1.6; 1.3 excess cases per 100 children, 95% CI −2.5 to 5.7).

Interpretation:

We found little evidence that children with higher probability of exposure to antenatal corticosteroids have higher rates of ADHD prescriptions in childhood, supporting the safety of antenatal corticosteroids for this neurodevelopmental outcome.

Maternal and neonatal trauma following operative vaginal delivery

Background:

Operative vaginal delivery (OVD) is considered safe if carried out by trained personnel. However, opportunities for training in OVD have declined and, given these shifts in practice, the safety of OVD is unknown. We estimated incidence rates of trauma following OVD in Canada, and quantified variation in trauma rates by instrument, region, level of obstetric care and institutional OVD volume.

Methods:

We conducted a cohort study of all singleton, term deliveries in Canada between April 2013 and March 2019, excluding Quebec. Our main outcome measures were maternal trauma (e.g., obstetric anal sphincter injury, high vaginal lacerations) and neonatal trauma (e.g., subgaleal hemorrhage, brachial plexus injury). We calculated adjusted and stabilized rates of trauma using mixed-effects logistic regression.

Results:

Of 1 326 191 deliveries, 38 500 (2.9%) were attempted forceps deliveries and 110 987 (8.4%) were attempted vacuum deliveries. The maternal trauma rate following forceps delivery was 25.3% (95% confidence interval [CI] 24.8%–25.7%) and the neonatal trauma rate was 9.6 (95% CI 8.6–10.6) per 1000 live births. Maternal and neonatal trauma rates following vacuum delivery were 13.2% (95% CI 13.0%–13.4%) and 9.6 (95% CI 9.0–10.2) per 1000 live births, respectively. Maternal trauma rates remained higher with forceps than with vacuum after adjustment for confounders (adjusted rate ratio 1.70, 95% CI 1.65–1.75) and varied by region, but not by level of obstetric care.

Interpretation:

In Canada, rates of trauma following OVD are higher than previously reported, irrespective of region, level of obstetric care and volume of OVD among hospitals. These results support a reassessment of OVD safety in Canada.

Practice Summary of Antimicrobial Therapy for Commonly Encountered Conditions in the Neonatal Intensive Care Unit: A Canadian Perspective

Neonates are highly susceptible to infections owing to their immature cellular and humoral immune functions, as well the need for invasive devices. There is a wide practice variation in the choice and duration of antimicrobial treatment, even for relatively common conditions in the NICU, attributed to the lack of evidence-based guidelines. Early decisive treatment with broad-spectrum antimicrobials is the preferred clinical choice for treating sick infants with possible bacterial infection. Prolonged antimicrobial exposure among infants without clear indications has been associated with adverse neonatal outcomes and increased drug resistance. Herein, we review and summarize the best practices from the existing literature regarding antimicrobial use in commonly encountered conditions in neonates.

Infants Born to Mothers Who Were SARS-CoV-2 Positive during Pregnancy and Admitted to Neonatal Intensive Care Unit

INTRODUCTION

Our objective was to compare neonatal outcomes and resource use of neonates born to mothers with SARS-CoV-2 positivity during pregnancy with neonates born to mothers without SARS-CoV-2 positivity.

METHODS

We conducted a two-country cohort study of neonates admitted between January 1, 2020, and September 15, 2021, to tertiary neonatal intensive care unit (NICU) in Canada and Sweden. Neonates from mothers who were SARS-CoV-2 positive during pregnancy were compared with three randomly selected NICU neonates of mothers who were not test-positive, matched on gestational age, sex, and birth weight (±0.25 SD). Subgroup analyses were conducted for neonates born <33 weeks' gestation and mothers who were SARS-CoV-2 positive ≤10 days prior to birth. Primary outcome was duration of respiratory support. Secondary outcomes were in-hospital mortality, neonatal morbidity, late-onset sepsis, receipt of breast milk at discharge, and length of stay.

RESULTS

There were 163 exposed and 468 matched neonates in Canada, and 303 exposed and 903 matched neonates in Sweden. There was no statistically significant difference in invasive or noninvasive respiratory support durations, mortality, respiratory and other neonatal morbidities, or resource utilizations between two groups in both countries in entire cohort and in subgroup analyses. Receipt of breast milk at discharge was lower in the Canadian neonates of mothers who were SARS-CoV-2 positive ≤10 days before birth (risk ratio 0.68, 95% CI: 0.57-0.82).

CONCLUSION

Maternal SARS-CoV-2 positivity was not associated with increased durations of respiratory support, morbidities, mortality, or length of hospital stay in Canada and Sweden among neonates admitted to tertiary NICU.

Decreasing Trend in Incidence of Late Onset Culture Positive Bloodstream Infections but Not Late Onset Meningitis in Preterm Infants <33 Weeks Gestation in Canadian Neonatal Intensive Care Unit

INTRODUCTION

Recent studies reported decreased incidence of late onset sepsis in the neonatal intensive care unit (NICU), but it is unclear whether this is also true for late onset meningitis. Recent reports that both meningitis and intraventricular hemorrhage (IVH) are associated with systemic inflammation also raise questions about an association between the 2.

METHODS

All preterm infants <33 weeks gestational age admitted to CNN NICUs from 2010 to 2018 were included. We compared incidence trends of late onset culture positive bloodstream infection (CPBSI) and late onset meningitis, and examined the association of meningitis and IVH (exposure), after adjustment for potential confounders.

RESULTS

Of 36,573 infants included, 32,198 had no infection, 3,977 had only late onset CPBSI and 398 had late onset meningitis. There was significant decrease in incidence of late onset CPBSI (14%-10%; adjusted odds ratio (AOR) = 0.93; 95% confidence interval [CI] 0.92, 0.95) but not late onset meningitis (1.6%-1.2%; AOR = 0.98; 95% CI 0.94, 1.01). Compared to infants with no IVH grade 3 or above, infants with IVH grade 3, or above had higher odds of late onset meningitis versus no infection (AOR 4.16; 95% CI 3.17, 5.44), and higher odds of late onset meningitis versus late onset CPBSI (AOR 4.11; 95% CI 3.08, 5.50).

CONCLUSIONS

There was a decreasing trend of late onset CPBSI but not late onset meningitis. An association between late onset meningitis and IVH grade 3 or above was observed. Late onset CPBSI and meningitis may have different risk factors and require different prevention strategies.

Quantifying Proximal Collecting Tubule Deficiency in Angiotensin-Converting Enzyme Inhibitor and Angiotensin II Receptor Blocker Fetopathy

INTRODUCTION

Angiotensin-Converting Enzyme Inhibitors and Angiotensin II Receptor Blockers (AAs) are used for several indications, with cessation recommended in pregnancy due to toxic effects. AA fetopathy phenotype is similar to renal tubular dysgenesis including reduced proximal convoluted tubules (PCTs). Our study aimed to quantify the reduction of PCTs in fetuses and infants with prenatal exposure to AAs.

MATERIALS AND METHODS

We identified 5 fetal AA exposure cases that underwent autopsy at our institution between 2011 and 2018 and compared with 5 gestational age-matched controls. Immunohistochemistry with CD10 and epithelial membrane antigen (EMA) was utilized.

RESULTS

CD10 and EMA identified a median PCT density of 19.0% ± 12.3% in AA fetopathy patients, significantly less than controls (52.8% ± 4.4%; p < 0.0001). One case with in utero cessation had a PCT density of 34.2% ± 0.2%. Among other AA fetopathy findings, 1 case demonstrated unilateral renal vein thrombosis and 4 had hypocalvaria.

CONCLUSIONS

We have quantified the reduction in AA fetopathy PCT density, and demonstrated in utero cessation may recover PCT differentiation. Future studies may benefit from calculating PCT percentage as a potential biomarker to correlate with post-natal renal function and maternal factors including medication type, dosage, duration, and time from medication cessation.

Relative effectiveness and safety of pharmacotherapeutic agents for patent ductus arteriosus (PDA) in preterm infants: a protocol for a multicentre comparative effectiveness study (CANRxPDA)

INTRODUCTION

Patent ductus arteriosus (PDA) is the most common cardiovascular problem that develops in preterm infants and evidence regarding the best treatment approach is lacking. Currently available medical options to treat a PDA include indomethacin, ibuprofen or acetaminophen. Wide variation exists in PDA treatment practices across Canada. In view of this large practice variation across Canadian neonatal intensive care units (NICUs), we plan to conduct a comparative effectiveness study of the different pharmacotherapeutic agents used to treat the PDA in preterm infants.

METHODS AND ANALYSIS

A multicentre prospective observational comparative-effectiveness research study of extremely preterm infants born <29 weeks gestational age with an echocardiography confirmed PDA will be conducted. All participating sites will self-select and adhere to one of the following primary pharmacotherapy protocols for all preterm babies who are deemed to require treatment.Standard dose ibuprofen (10 mg/kg followed by two doses of 5 mg/kg at 24 hours intervals) irrespective of postnatal age (oral/intravenous).Adjustable dose ibuprofen (oral/intravenous) (10 mg/kg followed by two doses of 5 mg/kg at 24 hours intervals if treated within the first 7 days after birth. Higher doses of ibuprofen up to 20 mg/kg followed by two doses of 10 mg/kg at 24 hours intervals if treated after the postnatal age cut-off for lower dose as per the local centre policy).Acetaminophen (oral/intravenous) (15 mg/kg every 6 hours) for 3-7 days.Intravenous indomethacin (0.1-0.3 mg/kg intravenous every 12-24 hours for a total of three doses).

OUTCOMES

The primary outcome is failure of primary pharmacotherapy (defined as need for further medical and/or surgical/interventional treatment following an initial course of pharmacotherapy). The secondary outcomes include components of the primary outcome as well as clinical outcomes related to response to treatment or adverse effects of treatment.

SITES AND SAMPLE SIZE

The study will be conducted in 22 NICUs across Canada with an anticipated enrollment of 1350 extremely preterm infants over 3 years.

ANALYSIS

To examine the relative effectiveness of the four treatment strategies, the primary outcome will be compared pairwise between the treatment groups using χ² test. Secondary outcomes will be compared pairwise between the treatment groups using χ² test, Student's t-test or Wilcoxon rank sum test as appropriate. To further examine differences in the primary and secondary outcomes between the four groups, multiple logistic or linear regression models will be applied for each outcome on the treatment groups, adjusted for potential confounders using generalised estimating equations to account for within-unit-clustering. As a sensitivity analysis, the difference in the primary and secondary outcomes between the treatment groups will also be examined using propensity score method with inverse probability weighting approach.

ETHICS AND DISSEMINATION

The study has been approved by the IWK Research Ethics Board (#1025627) as well as the respective institutional review boards of the participating centres.

TRIAL REGISTRATION NUMBER

NCT04347720.

Comparison of Multivariable Logistic Regression and Machine Learning Models for Predicting Bronchopulmonary Dysplasia or Death in Very Preterm Infants

Bronchopulmonary dysplasia (BPD) is the most prevalent and clinically significant complication of prematurity. Accurate identification of at-risk infants would enable ongoing intervention to improve outcomes. Although postnatal exposures are known to affect an infant's likelihood of developing BPD, most existing BPD prediction models do not allow risk to be evaluated at different time points, and/or are not suitable for use in ethno-diverse populations. A comprehensive approach to developing clinical prediction models avoids assumptions as to which method will yield the optimal results by testing multiple algorithms/models. We compared the performance of machine learning and logistic regression models in predicting BPD/death. Our main cohort included infants <33 weeks' gestational age (GA) admitted to a Canadian Neonatal Network site from 2016 to 2018 (n = 9,006) with all analyses repeated for the <29 weeks' GA subcohort (n = 4,246). Models were developed to predict, on days 1, 7, and 14 of admission to neonatal intensive care, the composite outcome of BPD/death prior to discharge. Ten-fold cross-validation and a 20% hold-out sample were used to measure area under the curve (AUC). Calibration intercepts and slopes were estimated by regressing the outcome on the log-odds of the predicted probabilities. The model AUCs ranged from 0.811 to 0.886. Model discrimination was lower in the <29 weeks' GA subcohort (AUCs 0.699-0.790). Several machine learning models had a suboptimal calibration intercept and/or slope (k-nearest neighbor, random forest, artificial neural network, stacking neural network ensemble). The top-performing algorithms will be used to develop multinomial models and an online risk estimator for predicting BPD severity and death that does not require information on ethnicity.

Development of a national neonatal intensive care unit-specific antimicrobial stewardship programme in Canada: protocol for a cohort study

INTRODUCTION

Early empiric treatment with broad-spectrum antimicrobials is common in neonatal intensive care units (NICU) due to the non-specific clinical presentation of infection. However, excessive and inappropriate antimicrobial use can lead to the emergence of drug-resistant organisms and adverse neonatal outcomes. This study aims to develop and implement a nationwide NICU-specific antimicrobial stewardship programme (ASP) to promote judicious antimicrobial use and control the emergence of multidrug-resistant organisms (MDROs) in Canada.

METHODS AND ANALYSIS

Our study population will include all very low-birth-weight neonates admitted to participating tertiary NICU in Canada. Based on the existing limited literature, we will develop consensus on NICU antimicrobial stewardship interventions to enhance best practices. Using an expanded Canadian Neonatal Network (CNN) platform, we will collect data on antimicrobial use and the susceptibility of organisms identified in clinical samples from blood and cerebrospinal fluid over a period of 2 years. These data will be used to provide all NICU stakeholders with benchmarked centre-adjusted antimicrobial use and MDRO prevalence reports. An ASP plan will be developed at both individual unit and national levels in the subsequent years. Knowledge translation strategies will be implemented through the well-established Evidence-based Practice for Improving Quality methodology.

ETHICS AND DISSEMINATION

Ethics for the study has been granted by the University of British Columbia Children's & Women's Research Ethics Board (H19-02490) and supported by CNN Executive Committee. The study results will be disseminated through national organisations and open access peer-reviewed publications.

TRIAL REGISTRATION NUMBER

NCT04388293.

Gastrointestinal hemodynamic changes during therapeutic hypothermia and after rewarming in neonatal hypoxic-Ischemic encephalopathy

BACKGROUND

Hypoxic-ischemic encephalopathy (HIE) is associated with disturbances in visceral blood flow velocities. Therapeutic Hypothermia (TH) is a standard of care; however, its impact on gastrointestinal blood flow in infants with HIE is unknown. The objective of this study was to assess gastrointestinal (GI) blood flow and left ventricle output (LVO) in infants with hypoxic-ischemic encephalopathy during whole body TH and after rewarming.

METHODS

Serial echocardiography and Doppler evaluation of intestinal blood flow (celiac (CA) and superior mesenteric (SMA) arteries) were prospectively performed in a cohort of 20 newborn infants with HIE at 4 time points during hypothermia and after rewarming. Demographic, clinical and biochemical data were collected and analyzed for their relevance.

RESULTS

Median gestational age and birth weight was 40 weeks (37-41) and 3410 g (2190-4950) respectively. Celiac and mesenteric artery flow remained low during hypothermia and rose significantly after rewarming [peak systolic velocity in CA (0.63 m/s to 0.77 m/s, p = 0.004) and SMA (0.43 m/s to 0.55 m/s, p = 0.001)]. This increase was temporally associated with increased left ventricular output (106 ml/kg/min to 149 ml/kg/min, p < 0.0001). Median age to reach 25% of the feeds was 5 days (1-7 days). All patients survived.

CONCLUSIONS

CA and SMA blood flow velocity and LVO did not vary during hypothermia but rose after rewarming. This may suggest protective effect of therapeutic hypothermia on gastrointestinal system. The association of these physiological changes with neonatal outcome needs further assessment.

Use of sildenafil in an infant with persistent pulmonary hypertension secondary to lung and renal hypoplasia - a case report

Background

Premature preterm rupture of membranes (PPROM) is reported to be associated with high rates of neonatal mortality and morbidity. Sildenafil has been used in infants with persistent pulmonary hypertension of newborn (PPHN) due to congenital diaphragmatic hernia (CDH) and bronchopulmonary dysplasia (BPD). Recently, Sildenafil has been evaluated as an alternative or adjunctive pulmonary vasodilator. This case report illustrates the use of early sildenafil for PPHN and right ventricular dysfunction in an unusual setting of lung and renal hypoplasia.

Case presentation

A male infant was born at 37 weeks with a birth weight of 2840 g. Rupture of membranes developed at approximately 24 weeks of gestational age (GA). Bilateral small kidneys (< 2 standard deviations below average) were detected on ultrasound (US) examination at 30 weeks of gestation. The baby developed pneumothorax and pulmonary hypertensive crisis towards the end of the first day. An echocardiogram showed a dilated right ventricle, moderate right ventricular systolic dysfunction, hypoplastic pulmonary arteries and a large patent ductus arteriosus with bidirectional flow. The patient was sedated, paralyzed, and inhaled nitric oxide was administered to decrease the pulmonary resistance. In anticipation of persistent pulmonary hypertension due to the hypoplastic lungs and small calibre of pulmonary arteries, sildenafil was started on day of life (DOL) 5 at a dosage of 0.25 mg/kg/dose Q8H and gradually increased to 2 mg/kg/dose Q8H on DOL 9. The patient was finally extubated on DOL 7 and weaned off of non-invasive respiratory support on DOL 26. Sildenafil was gradually weaned beginning on DOL 21 and discontinued on DOL 48. Repeat echocardiogram assessment at 3 months showed complete resolution of PHT and right ventricular dilatation.

Conclusions

We describe the early use of sildenafil in treating pulmonary hypertension associated with lung and renal hypoplasia in a non-CDH patient. Following this treatment the patient made a full recovery from right ventricular dysfunction.

Prevalence and clinical impact of methicillin-resistant Staphylococcus aureus colonization among infants at a level III neonatal intensive care unit

BACKGROUND

Methicillin-resistant Staphylococcus aureus (MRSA) is a well-known nosocomial pathogen in neonatal intensive care unit (NICU) patients. Studies on the impact of MRSA colonization on neonatal morbidities are scarce.

METHODS

We conducted a 1:3 matched cohort study among infants with and without MRSA colonization, born between January 2010 and June 2014, in a tertiary NICU to review their demographic characteristics and outcomes.

RESULTS

During the study period, rates of MRSA colonization and bacteremia were found to be 0.68% and 0.10%, respectively. No differences in demographic characteristics, mortality, and major morbidities were identified among infants with and without MRSA colonization.

CONCLUSIONS

We reported a low rate of MRSA colonization in infants admitted to our NICU, without impact on mortality and inhospital morbidity. Further large-scale studies are needed to understand the implications and cost-effectiveness of active MRSA surveillance.

A national survey of the enteral feeding practices in Canadian neonatal intensive care units

Aim

Nutrition affects the growth and neurodevelopmental outcomes of preterm infants, yet controversies exist about the optimal enteral feeding regime. The objective of this study was to compare enteral feeding guidelines in Canadian neonatal intensive care units (NICUs).

Method

The research team identified key enteral feeding practices of interest. Canadian Neonatal Network site investigators at 30 Level 3 NICUs were contacted to obtain a copy of their 2016 to 2017 feeding guidelines for infants who weighed less than 1,500 g at birth. Each guideline was reviewed to compare recommendations around the selected feeding practices.

Results

Five of the 30 NICUs did not have a feeding guideline. The other 25 NICUs used 22 different enteral feeding guidelines. The guidelines in 40% of those NICUs recommend commencing minimal enteral nutrition (MEN) within 24 hours of birth and maintaining that same feeding volume for 24 to 96 hours. In 40% of NICUs, the guideline recommended that MEN be initiated at a volume of 5 to 10 mL/kg/day for infants born at <1,000 g. Guidelines in all 25 NICUs recommend the use of bovine-based human milk fortifier (HMF), and in 56% of NICUs, it is recommended that HMF be initiated at a total fluid intake of 100 mL/kg/day. Guidelines in only 16% of NICUs recommended routine gastric residual checks. Donor milk and probiotics are used in 76% and 72% of the 25 NICUs, respectively.

Conclusion

This study revealed substantial variability in recommended feeding practices for very low birth weight infants, underscoring the need to establish a national feeding guideline for this vulnerable group.

Duration of Initial Empirical Antibiotic Therapy and Outcomes in Very Low Birth Weight Infants

: media-1vid110.1542/5984244681001PEDS-VA_2018-2286Video Abstract BACKGROUND: Overuse of antibiotics can facilitate antibiotic resistance and is associated with adverse neonatal outcomes. We studied the association between duration of antibiotic therapy and short-term outcomes of very low birth weight (VLBW) (<1500 g) infants without culture-proven sepsis.

METHODS

We included VLBW infants admitted to NICUs in the Canadian Neonatal Network between 2010-2016 who were exposed to antibiotics but did not have culture-proven sepsis in the first week. Antibiotic exposure was calculated as the number of days an infant received antibiotics in the first week of life. Composite primary outcome was defined as mortality or any major morbidity (severe neurologic injury, retinopathy of prematurity, necrotizing enterocolitis, chronic lung disease, or hospital-acquired infection).

RESULTS

Of the 14 207 included infants, 21% (n = 2950), 38% (n = 5401), and 41% (n = 5856) received 0, 1 to 3, and 4 to 7 days of antibiotics, respectively. Antibiotic exposure for 4 to 7 days was associated with higher odds of the composite outcome (adjusted odds ratio 1.24; 95% confidence interval [CI] 1.09-1.41). Each additional day of antibiotic use was associated with 4.7% (95% CI 2.6%-6.8%) increased odds of composite outcome and 7.3% (95% CI 3.3%-11.4%) increased odds in VLBW infants at low risk of early-onset sepsis (born via cesarean delivery, without labor and without chorioamnionitis).

CONCLUSIONS

Prolonged empirical antibiotic exposure within the first week after birth in VLBW infants is associated with increased odds of the composite outcome. This practice is a potential target for antimicrobial stewardship.

Comparing the Quality of Cardiopulmonary Resuscitation Performed at the Over-the-Head Position and Lateral Position of Neonatal Manikin

Background: Recent neonatal resuscitation guidelines suggest to perform chest compression (CC) at over-the-head (OTH) position instead of lateral position when further interventions including umbilical venous access are needed. Little information is available regarding the quality of cardiopulmonary resuscitation at different positions. Our study compared the quality of CC and ventilation at OTH position vs. lateral position in simulated neonatal resuscitation. Methods: Thirty-nine neonatal practitioners who attended the NRP®-based Provider renewal course workshop participated this study. Laerdal QCPR infant model were used to collect the data (2-miutes continuous recording) on quality of CC and ventilation of all participants at OTH position and lateral position in randomized order, both coordinated with mask ventilation or endotracheal ventilation through a Neopuff^© T-piece system. The quality of CC and ventilation were compared. Participants also reported their demographics and opinions in anonymous questionnaires after the session. Results: The quality of CC and ventilation was not different when CPR was performed at OTH position and lateral position, in both mask and endotracheal ventilation. When CPR was performed with endotracheal ventilation, there were small faster frequencies of CC and ventilation at OTH position, compared with those at lateral position (p = 0.004). Most participants (87%) liked the CC performed at OTH position and had no adverse feedback. Conclusions: Performing CC at OTH position was generally well-received in simulated resuscitation; the quality of CC and ventilation at OTH position was not significantly different from that at lateral position, irrespective of mask or endotracheal ventilation.

Intrapartum magnesium sulfate is associated with neuroprotection in growth-restricted fetuses

BACKGROUND

Intrapartum magnesium sulfate administration is recommended for fetal neuroprotection in women with imminent very preterm birth. However, previous studies have not included or separately analyzed the outcomes of pregnancies with fetal growth restriction that were treated with intrapartum magnesium sulfate.

OBJECTIVE

We sought to evaluate the neonatal and neurodevelopmental outcomes of growth-restricted fetuses born <29 weeks' gestation and exposed to maternal intrapartum magnesium sulfate.

STUDY DESIGN

We conducted a retrospective cohort study of infants born <29 weeks' gestation from 2010 through 2011, admitted to participating Canadian Neonatal Network units, and followed by the Canadian Neonatal Follow-up Network centers. Growth restriction was defined either as estimated fetal or actual neonatal birthweight <10th percentile according to fetal or neonatal growth standards for gestational age and sex, respectively. Infants exposed to intrapartum magnesium sulfate were compared with unexposed infants. The primary outcome was composite of death or significant neurodevelopmental impairment at 18-36 months' corrected age. Secondary outcomes were death or any neurodevelopmental impairment at 18-36 months' corrected age. Neonatal morbidities were also compared.

RESULTS

Of the 336 growth-restricted fetuses, 112 (33%) received magnesium sulfate and of the 177 growth-restricted infants, 61 (34%) received magnesium sulfate. Administration of magnesium sulfate was at the discretion of the treating physician. Intrapartum magnesium sulfate was associated with reduced odds of composite of death or significant neurodevelopmental impairment for infants classified according to both fetal standards (adjusted odds ratio, 0.42; 95% confidence interval, 0.22-0.80) and neonatal standards (adjusted odds ratio, 0.44; 95% confidence interval, 0.20-0.98).

CONCLUSION

Intrapartum administration of magnesium sulfate to women with growth-restricted fetuses born <29 weeks' gestation was associated with reduced odds of composite of death or significant neurodevelopmental impairment.

Association of Antibiotic Utilization and Neurodevelopmental Outcomes among Extremely Low Gestational Age Neonates without Proven Sepsis or Necrotizing Enterocolitis

OBJECTIVE

The objective is to evaluate the association between antibiotic utilization and neurodevelopmental outcomes at 18 to 21 months' corrected age among extremely low gestational age neonates without culture-proven sepsis or necrotizing enterocolitis (NEC).

STUDY DESIGN

We conducted a retrospective cohort study of infants born between April 2009 and September 2011 at <29 weeks' gestation and admitted to the neonatal intensive care units contributing data to the Canadian Neonatal Network. Multivariable analysis was performed to examine the primary composite outcome of death or significant neurodevelopmental impairment (sNDI) in infants with various antibiotic utilization rates (AURs).

RESULT

There were 1,373 infants who fulfilled our inclusion criteria. Compared with infants in the lowest AUR quartile (Q1), those in the highest quartile (Q4) had higher odds of death or sNDI (adjusted odds ratio [AOR] = 7.44; 95% confidence interval [CI]: 4.55, 12.2) and death (AOR = 39.3; 95% CI: 16.1, 95.9).

CONCLUSION

Our results indicate an association between high AUR and a composite outcome of death or adverse neurodevelopmental outcomes at 18 to 21 months' corrected age.

Cardiovascular Associations with Abnormal Brain Magnetic Resonance Imaging in Neonates with Hypoxic Ischemic Encephalopathy Undergoing Therapeutic Hypothermia and Rewarming

OBJECTIVE

This article compares hemodynamic characteristics of neonates with hypoxic ischemic encephalopathy (HIE) receiving therapeutic hypothermia (TH) with normal versus abnormal brain magnetic resonance imaging (MRI).

METHODS

Serial echocardiography (echo) was performed within 24 hours, after 48 to 72 hours of cooling, within 24 hours of normothermia, and after starting feeds. Pulmonary hemodynamics, cardiac output, and ventricular function were evaluated. All neonates underwent brain MRI (day 4-5), per clinical standard of care. Clinical cardiovascular and echocardiography characteristics were compared between patients with normal versus abnormal MRI. Cardiovascular changes during TH and after rewarming were identified.

RESULTS

Twenty neonates at median gestation and birth weight of 40 weeks (interquartile range [IQR]: 39, 41) and 3,410 g (IQR: 2,885, 4,093), respectively, were enrolled. Increased median left ventricular output (LVO) (106-159 mL/kg/min, p < 0.001) and reduced isovolumic relaxation time (IVRT) (48-42 ms, p < 0.001) were seen after rewarming. Echocardiography evidence of pulmonary hypertension (PH) was identified in five neonates. Eight neonates (40%) had brain injury identified on MRI (watershed [n = 4], basal ganglia [n = 4]); this subgroup were more likely to have echo evidence of PH at 24 hours.

CONCLUSION

Longitudinal changes in cardiac output were noted in neonates with HIE during TH and rewarming. Echocardiography evidence of PH, however, was associated with abnormal MRI brain. The prognostic relevance of these physiologic changes requires more comprehensive delineation.

Association Between Antibiotic Use and Neonatal Mortality and Morbidities in Very Low-Birth-Weight Infants Without Culture-Proven Sepsis or Necrotizing Enterocolitis

IMPORTANCE

Excessive antibiotic use has been associated with altered bacterial colonization and may result in antibiotic resistance, fungemia, necrotizing enterocolitis (NEC), and mortality. Exploring the association between antibiotic exposure and neonatal outcomes other than infection-related morbidities may provide insight on the importance of rational antibiotic use, especially in the setting of culture-negative neonatal sepsis.

OBJECTIVE

To evaluate the trend of antibiotic use among all hospitalized very low-birth-weight (VLBW) infants across Canada and the association between antibiotic use rates (AURs) and mortality and morbidity among neonates without culture-proven sepsis or NEC.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective cohort study was conducted among VLBW infants (<1500 g) admitted to level III neonatal intensive care units between January 1, 2010, and December 31, 2014, using data obtained from the Canadian Neonatal Network database.

EXPOSURE

Duration of antibiotic use during the hospitalization period.

MAIN OUTCOMES AND MEASURES

The AUR was defined as the number of days an infant was exposed to 1 or more antimicrobial agents divided by the total length of hospital stay. The composite primary outcome was defined as mortality or major morbidity, including any of the following: persistent periventricular echogenicity or echolucency on neuroimaging, chronic lung disease, and stage 3 or higher retinopathy of prematurity. Multivariable regression analysis was used to calculate adjusted odds ratios (aORs) and 95% CIs for the association between AURs and outcomes.

RESULTS

Among 13 738 eligible VLBW infants, 11 669 (84.9%) (mean [SD] gestational age, 27.7 [2.5] weeks; 47.4% female) received antibiotics during their hospital course and were included in the study. The annual AUR decreased from 0.29 in 2010 to 0.25 in 2014 (slope for the best-fit line, -0.011; 95% CI, -0.016 to -0.006; P < .01), which occurred in parallel with a reduction in the rate of late-onset sepsis from 19.0% in 2010 to 13.8% in 2014 during the same period. Of the 11 669 infants who were treated with antibiotics of varying duration during their hospital stay, 2845 were diagnosed as having sepsis-related complications. Among the remaining 8824 infants without early-onset sepsis, late-onset sepsis, or NEC, a 10% increase in the AUR was associated with an increased odds of the primary composite outcome (aOR, 1.18; 95% CI, 1.13-1.23), mortality (aOR, 2.04; 95% CI, 1.87-2.21), and stage 3 or higher retinopathy of prematurity (aOR, 1.18; 95% CI, 1.06-1.32).

CONCLUSIONS AND RELEVANCE

Antibiotic use in VLBW infants decreased between 2010 and 2014 in Canada. However, among infants without culture-proven sepsis or without NEC, higher AURs were associated with adverse neonatal outcomes.

Percutaneously Inserted Central Catheter-Related Pleural Effusion in a Level III Neonatal Intensive Care Unit: A 5-Year Review (2008-2012)

BACKGROUND

Although peripherally inserted central catheters (PICCs) provide vascular access in newborns who require parenteral nutrition and medications, they can be associated with complications that lead to significant morbidity and mortality.

OBJECTIVES

To describe the characteristics of pleural effusion (PLE) associated with PICC use in a large level III neonatal intensive care unit.

DESIGN/METHODS

A retrospective review of PICC-related PLE in newborns was conducted over a 5-year period, from 2008-2012.

RESULTS

A total of 926 PICCs were inserted, accounting for 17,606 catheter days. PICC-related PLE was identified in 7 infants, with an incidence of 0.4 per 1000 catheter days. Infants who developed PLE had a median gestational age of 28 weeks (range, 24-38 weeks) and birth weight of 735 g (range, 500-2975 g). PICCs were inserted at a median age of 4 days (range, 3-11 days). The median time from catheter insertion to the development of PLE was 16 days (range, 7-75 days). In all cases, the catheter tips were centrally located at the time of insertion but migrated to the subclavian veins or tributaries at the time of the events.

CONCLUSION

PICC-related PLE can be associated with the migration of PICC tips to noncentral locations, despite optimal positioning of the tip at the time of insertion. Attention should be paid to migration of catheter tips on subsequent x-ray films. For PICCs inserted via upper limb or scalp, serial follow-up x-rays, beginning 1 week after insertion, may be helpful to detect migration of catheter tips and identify patients at risk.

Use of peripherally inserted central catheters (PICC) via scalp veins in neonates

OBJECTIVE

The objective of this study is to describe the use and complications of peripherally inserted central catheters (PICC) via scalp veins in neonates.

METHODS

A retrospective review of neonates who had PICCs inserted, between January 2010 and June 2013, in the NICU at Children's and Women's Health Center of British Columbia.

RESULTS

During the study period, 689 PICCs were inserted over a total of 46 728 NICU patient days. The PICC insertion sites were scalp veins (69), upper limb veins (471), and lower limb veins (149). The mean catheter durations were 17 d, 19 d, and 18 d for PICCs inserted through scalp, upper limb, and lower limb veins, respectively. The complication rates were 23%, 23%, and 15% for insertion via scalp, upper, and lower limb veins, respectively. Centrally placed PICCs at the time of insertion were more likely to remain in situ for longer than one week (p < 0.001). The incidence of central line-associated blood stream infection was 4.4, 6.4, and 3.4 per 1000 catheter days, respectively, for scalp, upper, and lower limb PICCs.

CONCLUSIONS

Insertion of PICC via the scalp veins are feasible and not associated with higher complication rates compared with insertions via other sites.

A Patent Ductus Arteriosus Severity Score Predicts Chronic Lung Disease or Death before Discharge

OBJECTIVES

To test the hypothesis that a patent ductus arteriosus (PDA) severity score (PDAsc) incorporating markers of pulmonary overcirculation and left ventricular (LV) diastolic function can predict chronic lung disease or death before discharge (CLD/death).

STUDY DESIGN

A multicenter prospective observational study was conducted for infants <29 weeks gestation. An echocardiogram was carried out on day 2 to measure PDA diameter and maximum flow velocity, LV output, diastolic flow in the descending aorta and celiac trunk, and variables of LV function using tissue Doppler imaging. Predictors of CLD/death were identified using logistic regression methods. A PDAsc was created and a receiver operating characteristic curve was constructed to assess its ability to predict CLD/death.

RESULTS

We studied 141 infants at a mean (SD) gestation and birthweight of 26 (1.4) weeks and 952 (235) g, respectively. Five variables were identified that were independently associated with CLD/death (gestation at birth, PDA diameter, maximum flow velocity, LV output, and LV a' wave). The PDAsc had a range from 0 (low risk) to 13 (high risk). Infants who developed CLD/death had a higher score than those who did not (7.3 [1.8] vs 3.8 [2.0], P < .001). PDAsc had an area under the curve of 0.92 (95% CI 0.86-0.97, P < .001) for the ability to predict CLD/death. A PDAsc cut-off of 5 has sensitivity and specificity of 92% and 87%, and positive and negative predictive values of 92% and 82%, respectively.

CONCLUSIONS

A PDAsc on day 2 can predict the later occurrence of CLD/death further highlighting the association between PDA significance and morbidity.

Ion recombination corrections of ionization chambers in flattening filter-free photon radiation

The flattening filter free (FFF) X-rays can provide much higher dose rate at the treatment target compared to the conventional flattened X-rays. However, the substantial increase of dose rate for FFF beams may affect the ion recombination correction factor, which is required for accurate measurements using ionization chambers in clinical dosimetry. The purpose of this work is to investigate the ion recombination of three types of commonly used ion chambers (Farmer, PinPoint and plane-parallel) in the FFF photon radiation. Both 6 MV and 10 MV flattened and FFF beams were fully commissioned on a Varian TrueBeam linear accelerator. The ion recombination correction factor, P(ion), was determined using the two-voltage technique for a 0.6 cc Farmer chamber, a 0.015 cc PinPoint chamber, and a 0.02 cc parallel-plate chamber at different source-to-axis distances (SAD) in a solid water phantom or water tank phantom at a depth of 10 cm in a 10 × 10 cm(2) field. Good repeatability of measurements was demonstrated. Less than 1% difference in P(ion) between the flattened and FFF photons for all three ion chambers was observed. At a SAD of 100 cm and a depth of 10 cm for a 10 × 10 cm(2) field, P(ion) for the Farmer chamber was 1.004 and 1.008 for the 6 MV flattened and FFF beams, respectively. At the same setup using the Farmer chamber, P(ion) was 1.002 and 1.015 for the 10MV flattened and FFF beams, respectively. All P(ion) results for the Farmer, PinPoint, or parallel plate chamber in the 6 MV and 10 MV flattened and FFF beams were within 2% from the unity (1 ≤ P(ion) < 1.02). The P(ion) ratio of the FFF to flattened beams was 0.99~1.01 for both 6 MV and 10 MV photons. The ion recombination effect of the Farmer, PinPoint, and plane-parallel chamber in the FFF beams is not substantially different from that in the conventional flattened beams.