The evidence for high flow nasal cannula devices in infants.

High flow nasal cannula (HFNC) devices deliver an adjustable mixture of heated and humidified oxygen and air at a variable flow rate. Over recent years HFNC devices have become a frequently used method of non-invasive respiratory support in infants and preterm neonates that is generally popular amongst clinicians and nursing staff due to ease of use and being well tolerated by patients. Despite this rapid adoption relatively little is known about the exact mechanisms of action of HFNC however and only recently have data from randomised controlled trials started to become available. We describe the features of a modern HFNC device and discuss current knowledge about the mechanisms of action and results of clinical studies in preterm neonates and infants with bronchiolitis. We also highlight future areas of research that are likely to increase our understanding, inform best clinical practice and strengthen the evidence base for the use of HFNC.

Characteristics of children requiring admission to neonatal care and paediatric intensive care before the age of 2 years in England and Wales: a data linkage study.

OBJECTIVE: To quantify the characteristics of children admitted to neonatal units (NNUs) and paediatric intensive care units (PICUs) before the age of 2 years. DESIGN: A data linkage study of routinely collected data. SETTING: National Health Service NNUs and PICUs in England and Wales PATIENTS: Children born from 2013 to 2018. INTERVENTIONS: None. MAIN OUTCOME MEASURE: Admission to PICU before the age of 2 years. RESULTS: A total of 384 747 babies were admitted to an NNU and 4.8% (n=18 343) were also admitted to PICU before the age of 2 years. Approximately half of all children admitted to PICU under the age of 2 years born in the same time window (n=18 343/37 549) had previously been cared for in an NNU.The main reasons for first admission to PICU were cardiac (n=7138) and respiratory conditions (n=5386). Cardiac admissions were primarily from children born at term (n=5146), while respiratory admissions were primarily from children born preterm (<37 weeks' gestational age, n=3550). A third of children admitted to PICU had more than one admission. CONCLUSIONS: Healthcare professionals caring for babies and children in NNU and PICU see some of the same children in the first 2 years of life. While some children are following established care pathways (eg, staged cardiac surgery), the small proportion of children needing NNU care subsequently requiring PICU care account for a large proportion of the total PICU population. These differences may affect perceptions of risk for this group of children between NNU and PICU teams.

Tracking national neonatal transport activity and metrics using the UK Neonatal Transport Group dataset 2012-2021: a narrative review.

There are no internationally agreed descriptors for categories of neonatal transports which facilitate comparisons between settings. To continually review and enhance neonatal transport care we need robust categories to develop benchmarks. This review aimed to report on the development and application of key measures across a national neonatal transport service. The UK Neonatal Transport Group (UK-NTG) developed a core dataset and benchmarks for transported infants and collected annual national data. Data were reported back to teams to allow benchmarking and improvements. From 2012 to 2021, the rate of UK neonatal transfers increased from 18 to 22/1000 live births despite a falling birth rate. Neonatal transfers on nitric oxide increased until 2016 before plateauing. The proportion of transport services able to provide high frequency oscillation and servo-controlled therapeutic hypothermia increased over the study period. High-flow nasal cannula oxygen use increased, becoming the most frequently used non-invasive respiratory support mode. For infants <27 weeks of gestational age, transfers for uplift of care in the first 3 days of life have fallen from 420 (2016) to 288 (2020/2021) and for lack of neonatal capacity from 24 (2016) to 2 (2020/2021). The rate of ventilated infants completing transfer with CO2 out of the benchmark range varied from 9% to 13% with marked variation between transport services' rates of hypocapnia (0-10%) and hypercapnia with acidosis (0-9%). The development of the UK-NTG dataset supports national tracking of activity and clinical trends allowing comparison of patient-focused benchmarks across teams.

Diaphragm electrical activity during weaning of nasal high-flow therapy in preterm infants.

OBJECTIVE: To determine whether electrical activity of the diaphragm (Edi) changes with weaning nasal high-flow (HF) therapy in preterm infants according to a standardised protocol. DESIGN: Prospective observational cohort study. SETTING: Neonatal intensive care unit. PATIENTS: Preterm infants born at <32 weeks gestation, receiving nasal HF as part of routine clinical care. INTERVENTIONS: Infants recruited to the study had their HF weaned according to set clinical criteria. Edi was measured using a modified gastric feeding tube serially from baseline (pre-wean) to 24-hours post-wean. MAIN OUTCOME MEASURES: Change in Edi from baseline was measured at four time points up to 24 hours after weaning. Minimum Edi during expiration, maximum Edi during inspiration and amplitude of the Edi signal (Edidelta) were measured. Clinical parameters (heart rate, respiratory rate and fraction of inspired oxygen) were also recorded. RESULTS: Forty preterm infants were recruited at a mean corrected gestational age of 31.6 (±2.7) weeks. Data from 156 weaning steps were analysed, 91% of which were successful. Edi did not change significantly from baseline during flow reduction steps, but a significant increase in diaphragm activity was observed when discontinuing HF (median increase in Edidelta immediately post-discontinuation 1.7 µV (95% CI: 0.6 to 3.0)) and at 24 hours 1.9 µV (95% CI: 0.7 to 3.8)). No significant difference in diaphragm activity was observed between successful and unsuccessful weaning steps. CONCLUSIONS: A protocolised approach to weaning has a high probability of success. Edi does not change with reducing HF rate, but significantly increases with discontinuation of HF from 2 L/min.

Estimated neonatal survival of very preterm births across the care pathway: a UK cohort 2016-2020.

OBJECTIVE: Currently used estimates of survival are nearly 10 years old and relate to only those babies admitted for neonatal care. Due to ongoing improvements in neonatal care, here we update estimates of survival for singleton and multiple births at 22+0 to 31+6 weeks gestational age across the perinatal care pathway by gestational age and birth weight. DESIGN: Retrospective analysis of routinely collected data. SETTING: A national cohort from the UK and British Crown Dependencies. PATIENTS: Babies born at 22+0 to 31+6 weeks gestational age from 1 January 2016 to 31 December 2020. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Survival to 28 days. RESULTS: Estimates of neonatal survival are provided for babies: (1) alive at the onset of care during the birthing process (n=43 763); (2) babies where survival-focused care was initiated (n=42 004); and (3) babies admitted for neonatal care (n=41 158). We have produced easy-to-use survival charts for singleton and multiple births. Generally, survival increased with increasing gestational age at birth and with increasing birth weight. For all births with a birthweight over 1000 g, survival was 90% or higher at all three stages of care. CONCLUSIONS: Survival estimates are a vital tool to support and supplement clinical judgement within perinatal care. These up-to-date, national estimates of survival to 28 days are provided based on three stages of the perinatal care pathway to support ongoing clinical care. These novel results are a key resource for policy and practice including counselling parents and informing care provision.

Subspecialty neonatal trainees views on being prepared for the consultant role.

Higher specialist training offers an opportunity to focus on non-clinical skills as well as clinical issues. The authors wished to determine whether doctors who complete neonatal higher specialist training in the UK feel prepared for the consultant role with respect to management, research and teaching, as well as clinical activities. A questionnaire related to the preparedness of the consultant to carry out a range of activities was sent to all doctors who were appointed to the UK higher specialist training programme in neonatology from 2002 to 2008 who were currently working as consultants. Seventy-one of the 83 eligible participants completed the questionnaire. Roles that consultants felt extremely well prepared for related to clinical care, communication, team-working, prioritising tasks, teaching and audit. Trainees reported that roles that they had been not at all well prepared for were related to roles in management and service delivery, medicolegal issues and complaints, job planning and personal development, supporting doctors in difficulty and chairing meetings. Four key themes emerged from the analysis of free-text responses regarding specialty training: the influence of shift patterns/service provision, the lack of non-clinical preparation, learning on the job as a consultant later on and problems with grid training itself. This study showed that for neonatal paediatrics in the UK, new consultants feel confident about managing ill babies but are unprepared for other aspects of the consultant's role. Neonatal higher specialist training needs to allow opportunities for non-clinical training.

Understanding ethnic inequalities in stillbirth rates: a UK population-based cohort study.

OBJECTIVES: To investigate inequalities in stillbirth rates by ethnicity to facilitate development of initiatives to target those at highest risk. DESIGN: Population-based perinatal mortality surveillance linked to national birth and death registration (Mothers and Babies: Reducing Risk through Audits and Confidential Enquiries across the UK). SETTING: UK. PARTICIPANTS: 4 391 569 singleton births at ≥24+0 weeks gestation between 2014 and 2019. MAIN OUTCOME MEASURES: Stillbirth rate difference per 1000 total births by ethnicity. RESULTS: Adjusted absolute differences in stillbirth rates were higher for babies of black African (3.83, 95% CI 3.35 to 4.32), black Caribbean (3.60, 95% CI 2.65 to 4.55) and Pakistani (2.99, 95% CI 2.58 to 3.40) ethnicities compared with white ethnicities. Higher proportions of babies of Bangladeshi (42%), black African (39%), other black (39%) and black Caribbean (37%) ethnicities were from most deprived areas, which were associated with an additional risk of 1.50 stillbirths per 1000 births (95% CI 1.32 to 1.67). Exploring primary cause of death, higher stillbirth rates due to congenital anomalies were observed in babies of Pakistani, Bangladeshi and black African ethnicities (range 0.63-1.05 per 1000 births) and more placental causes in black ethnicities (range 1.97 to 2.24 per 1000 births). For the whole population, over 40% of stillbirths were of unknown cause; however, this was particularly high for babies of other Asian (60%), Bangladeshi (58%) and Indian (52%) ethnicities. CONCLUSIONS: Stillbirth rates declined in the UK, but substantial excess risk of stillbirth persists among babies of black and Asian ethnicities. The combined disadvantage for black, Pakistani and Bangladeshi ethnicities who are more likely to live in most deprived areas is associated with considerably higher rates. Key causes of death were congenital anomalies and placental causes. Improved strategies for investigation of stillbirth causes are needed to reduce unexplained deaths so that interventions can be targeted to reduce stillbirths.

Physiological effects of high-flow nasal cannula therapy in preterm infants.

OBJECTIVE: High-flow nasal cannula (HFNC) therapy is increasingly used in preterm infants despite a paucity of physiological studies. We aimed to investigate the effects of HFNC on respiratory physiology. STUDY DESIGN: A prospective randomised crossover study was performed enrolling clinically stable preterm infants receiving either HFNC or nasal continuous positive airway pressure (nCPAP). Infants in three current weight groups were studied: <1000 g, 1000-1500 g and >1500 g. Infants were randomised to either first receive HFNC flows 8-2 L/min and then nCPAP 6 cm H2O or nCPAP first and then HFNC flows 8-2 L/min. Nasopharyngeal end-expiratory airway pressure (pEEP), tidal volume, dead space washout by nasopharyngeal end-expiratory CO2 (pEECO2), oxygen saturation and vital signs were measured. RESULTS: A total of 44 preterm infants, birth weights 500-1900 g, were studied. Increasing flows from 2 to 8 L/min significantly increased pEEP (mean 2.3-6.1 cm H2O) and reduced pEECO2 (mean 2.3%-0.9%). Tidal volume and transcutaneous CO2 were unchanged. Significant differences were seen between pEEP generated in open and closed mouth states across all HFNC flows (difference 0.6-2.3 cm H2O). Infants weighing <1000 g received higher pEEP at the same HFNC flow than infants weighing >1000 g. Variability of pEEP generated at HFNC flows of 6-8 L/min was greater than nCPAP (2.4-13.5 vs 3.5-9.9 cm H2O). CONCLUSIONS: HFNC therapy produces clinically significant pEEP with large variability at higher flow rates. Highest pressures were observed in infants weighing <1000 g. Flow, weight and mouth position are all important determinants of pressures generated. Reductions in pEECO2 support HFNC's role in dead space washout.

Variability in Very Preterm Stillbirth and In-Hospital Mortality Across Europe.

BACKGROUND AND OBJECTIVE: Stillbirth and in-hospital mortality rates associated with very preterm births (VPT) vary widely across Europe. International comparisons are complicated by a lack of standardized data collection and differences in definitions, registration, and reporting. This study aims to determine what proportion of the variation in stillbirth and in-hospital VPT mortality rates persists after adjusting for population demographics, case-mix, and timing of death. METHODS: Standardized data collection for a geographically defined prospective cohort of VPTs (22+0-31+6 weeks gestation) across 16 regions in Europe. Crude and adjusted stillbirth and in-hospital mortality rates for VPT infants were calculated by time of death by using multinomial logistic regression models. RESULTS: The stillbirth and in-hospital mortality rate for VPTs was 27.7% (range, 19.9%-35.9% by region). Adjusting for maternal and pregnancy characteristics had little impact on the variation. The addition of infant characteristics reduced the variation of mortality rates by approximately one-fifth (4.8% to 3.9%). The SD for deaths <12 hours after birth was reduced by one-quarter, but did not change after risk adjustment for deaths ≥12 hours after birth. CONCLUSIONS: In terms of the regional variation in overall VPT mortality, over four-fifths of the variation could not be accounted for by maternal, pregnancy, and infant characteristics. Investigation of the timing of death showed that these characteristics only accounted for a small proportion of the variation in VPT deaths. These findings suggest that there may be an inequity in the quality of care provision and treatment of VPT infants across Europe.

The state of neonatal transport services in the UK.

Neonatal transfer services across the UK have evolved at different rates, using a variety of approaches. Scotland, Northern Ireland and most recently Wales have adopted a more centralised approach than in England, where due to comparative population size transport services have developed alongside neonatal network boundaries. Despite considerable investment, transport provision remains variable in some areas and there are continuing issues common to most regions, including service provision and configuration, training, competencies and audit. Further development is required to optimise the use of available resources and develop benchmarking to ensure a high quality sustainable service.

Who should staff neonatal transport teams?

Neonatal transport is variously staffed by diverse combinations of nurses, doctors and paramedical staff. There is no evidence that neonatal transport undertaken with staff from any particular professional background results in improved outcomes for infants; instead, it appears that beneficial outcomes result from using staff who are specifically trained in transport practice, regardless of their professional background. Core transport competencies that are transferrable should be a routine part of the training of transport team members.

Reduced anti-PRP antibody response to Hib immunisation in preterm (<32 weeks) UK infants who received inactivated polio (eIPV).

A vaccine containing inactivated polio (eIPV) (Pediacel) is now used in the UK. The effect of the eIPV on other components is not well understood. We studied Haemophilus influenzae type b (Hib) and tetanus responses in preterm infants, <32 weeks gestation at birth, immunised with the (then) standard UK primary vaccines and either oral polio vaccine (OPV) or eIPV and analysed the effect showing reduced Hib responses with eIPV.

Haemophilus influenzae type b immunization in infants in the United Kingdom: effects of diphtheria/tetanus/acellular pertussis/Hib combination vaccine, significant prematurity, and a fourth dose.

OBJECTIVE: To measure anti-polyribosylribitolphosphate (PRP) antibody and anti-tetanus toxoid (TT) antibody responses in UK infants to explore the effects of (1) immunization with an acellular diphtheria/tetanus/pertussis/Haemophilus influenzae type b (DTPHib) combination vaccine, (2) significant preterm delivery, and (3) a fourth dose of conjugated Hib vaccine (PRP-T) in those with a low anti-PRP antibody (<1.0 microg/mL) after primary immunization. METHODS: A prospective study was conducted in 4 tertiary neonatal units at a time when 2 types of DTPHib vaccines were used interchangeably in the United Kingdom for primary immunization: acellular (DTPaHib) and whole cell. Timing and type of all vaccine doses were as per standard UK practice. Blood was taken before and after immunization. A total of 166 preterm and 45 term infants completed the study; 97 (15 term) infants who had anti-PRP antibody <1.0 microg/mL were offered a fourth dose of PRP-T; 61 (55 preterm) then had repeat antibody measurements. Anti-PRP and anti-TT antibody after primary immunization relative to gestation and number of whole cell vaccine doses received was measured, as well as anti-PRP antibody after a fourth dose of PRP-T. RESULTS: A total of 49% of preterm and 33% of term infants had anti-PRP antibody <1.0 microg/mL after full primary immunization. Receipt of 1 or more acellular vaccine doses was associated with lower anti-PRP antibody, a dose response effect being observed. Preterm infants were less likely to have anti-PRP antibody >1.0 microg/mL compared with term infants. A total of 93% of infants who were given a fourth dose had anti-PRP antibody >1.0 microg/mL. Anti-TT antibody responses were satisfactory for all infants but also reduced by each DTPaHib dose received. CONCLUSION: Infants who receive DTPaHib, are significantly preterm, or who do not receive a fourth dose of conjugated Hib vaccine may be at increased risk for Hib disease.

Population-based outcomes after acute antenatal transfer.

Acute antenatal transfer to specialist centres is an accepted practice but few or no regular data are collected regarding the numbers of transfers performed or subsequent pregnancy outcome. We wished to determine the numbers, and the maternal and fetal outcomes following acute antenatal transfer between consultant obstetric units in the former Northern Region of the UK over a 12-month period (1 January-31 December 99). This is a geographically defined population in terms of provision of perinatal services. All acute antenatal transfers were notified centrally. Data pertaining to each transfer were collected at the time of transfer. Subsequent maternal and fetal outcomes were determined from patient records and neonatal databases. The regional annual acute antenatal transfer rate was 3.7 per 1000 deliveries. Most were for fetal reasons, although transfer rates varied between hospitals. The decision to transfer was influenced by distance and availability of paediatric staff. Even units that have similar characteristics show considerable variation in their transfer rates. No adverse incidents occurred during transfer and no major changes in maternal management occurred following transfer. Twenty-four per cent of women remained undelivered following transfer. Women with preterm labour in the absence of ruptured membranes were less likely to deliver than those transferred for other reasons and if they did deliver, their infants were also less likely to need intensive care. We believe audit of acute antenatal transfers should be routinely undertaken. Numbers of transfers might be reduced if delivery and the need for neonatal intensive care could be predicted with greater accuracy. The psychological and financial costs of transfer to women and healthcare providers need to be addressed.