Frequency of respiratory deterioration after immunisation in preterm infants

A Improving Birth-dose Hepatitis-B Vaccination in a Tertiary Level IV Neonatal Intensive Care Unit

Background

Perinatal hepatitis B is a global public health concern. To reduce perinatal hepatitis B and its complications, the Hepatitis B vaccine (HBV) is recommended by the New York State Department of Health and Advisory Committee on Immunization Practices within 24 hours of life for infants born with a birth weight ≥2000 g. Infants admitted to the neonatal intensive care unit (NICU) weighing over 2000 g missed their birth dose HBV frequently, which prompted the implementation of a quality improvement initiative to increase birth dose HBV immunization in a level IV NICU in New York.

Methods

May 2019 to April 2021 baseline data showed the birth dose HBV rate of infants born ≥2000 g at 24% and 31% within 12 and 24 hours, respectively. The multidisciplinary QI team identified barriers using an Ishikawa cause-and-effect diagram. Our interventions included multidisciplinary collaboration, electronic medical record reminders, education, posters, and improved communication between staff and parents. We aimed to achieve a 25% improvement from the baseline.

Results

After 19 months of QI interventions (four Plan-Do-Study-Act cycles), the rate of administering birth dose HBV within 12 hours of life increased from 24% to 56% and within 24 hours from 31% to 64%. Process measure compliance improved, exceeding the 25% target, and showed sustained improvement.

Conclusion

This QI initiative improved the rate of eligible infants receiving HBV within the first 24 hours of life in the NICU. This work can serve as a model for other healthcare institutions to improve HBV immunization rates in NICUs.

Hexavalent vaccines in preterm infants: an update by Italian Society of Pediatric Allergy and Immunology jointly with the Italian Society of Neonatology

Hexavalent vaccines, protecting against six diseases (diphtheria, tetanus, pertussis [DTaP], poliovirus, hepatitis B virus [HBV], and Haemophilus influenzae type b [Hib], are routinely the standard of care in Europe. The use of combined vaccines allows the reduction of number of injections and side effects, the reduction of costs, and the increase in adherence of the family to the vaccination schedule both in terms of the number of doses and timing. The safety profile, efficacy and effectiveness of hexavalent vaccines have been extensively documented in infants and children born at term, and data are accumulating in preterm infants. Hexavalent vaccines are particularly important for preterm infants, who are at increased risk for severe forms of vaccine preventable diseases. However, immunization delay has been commonly reported in this age group. All the three hexavalent vaccines currently marketed in Italy can be used in preterm infants, and recent data confirm that hexavalent vaccines have a similar or lower incidence of adverse events in preterm compared to full-term infants; this is likely due to a weaker immune system response and reduced ability to induce an inflammatory response in preterm infants. Apnoea episodes are the adverse events that can occur in the most severe preterm infants and / or with history of respiratory distress. The risk of apnoea after vaccination seems to be related to a lower gestational age and a lower birth weight, supporting the hypothesis that it represents an unspecific response of the preterm infant to different procedures. High seroprotection rates have been reported in preterm infants vaccinated with hexavalent vaccine. However, a lower gestational age seems to be associated with lower antibody titres against some vaccine antigens (e.g. HBV, Hib, poliovirus serotype 1, and pertussis), regardless of the type of hexavalent vaccine used. Waiting for large effectiveness studies, hexavalent vaccines should be administered in preterm infants according to the same schedule recommended for infants born at term, considering their chronological age and providing an adequate monitoring for cardio-respiratory events in the 48–72 h after vaccination, especially for infants at risk of recurrence of apnoea.

Timeliness of immunisations in preterm infants in the Netherlands

BACKGROUND

In the Netherlands, preterm infants receive the immunisations at the same chronological age as recommended for term infants without correction for gestational age (GA). The aim of this paper was to describe the timeliness of the routine Dutch national immunisation schedule in preterm infants in their first year of life and to evaluate possible determinants of delay.

METHODS

Preterm infants were prospectively recruited between October 2015 and October 2017 and stratified according to GA (<28, 28-32 and 32-36 weeks). Data from the baseline parental questionnaire, monthly parental questionnaires and medical records were used to determine the immunisation age and proportion of infants timely receiving the first immunisations (between 42 and 63 days). Results were compared between the GA and birth weight (BW) groups. Determinants associated with timeliness of immunisation were studied by multivariate logistic regression analysis.

RESULTS

Timely start of immunisation occurs in 60.5% of preterm infants in the Netherlands. The proportion of infants receiving the first immunisation on time was lowest for the group with GA <28 weeks (37%). The mean age of the first immunisation across all GA groups was 62.7 days (range 33-118) and differed significantly between GA group <28 weeks and the other two GA groups of 28-32 and 32-36 weeks (p < 0.001). Similar results were seen when stratified by BW. Multivariate analysis showed that low socioeconomic status (SES) and prolonged hospitalisation beyond 37 weeks each negatively influenced timeliness of the first immunisation.

CONCLUSION

These findings indicate that start of immunisations was often delayed in prematures and differs for different GA groups, being lowest (37%) in infants <28 weeks GA. Lower SES and prolonged hospital stay beyond 37 weeks GA are important determinants of timeliness. Efforts to improve timeliness should focus most on counselling parents in lower SES.

Update on vaccination of preterm infants: a systematic review about safety and efficacy/effectiveness. Proposal for a position statement by Italian Society of Pediatric Allergology and Immunology jointly with the Italian Society of Neonatology

INTRODUCTION

Preterm infants (PIs) are at increased risk of vaccine-preventable diseases (VPDs). However, delayed vaccination start and low vaccine coverage are still reported. Areas covered: This systematic review includes 37 articles on preterm vaccination published in 2008-2018 in PubMed. Both live attenuated and inactivated vaccines are safe and well tolerated in PIs. Local reactions, apnea, and reactivity changes are the most frequently reported adverse events. Lower gestational age and birth weight, preimmunization apnea, longer use of continuous positive airway pressure (CPAP) are risk factors for apnea. The proportion of PIs who develop protective humoral and cellular immunity is generally similar to full terms although later gestational age is associated with increased antibody IgG concentrations (i.e. against certain pneumococcal serotypes, influenza, hepatitis B virus and poliovirus 1) and increased mononuclear cells proliferation (i.e. after inactivated poliovirus). Expert opinion: PIs can be safely and adequately protected by available vaccines with the same schedule used for full terms. Data at this regard have been retrieved by studies using a 3-dose primary series for pneumococcal and hexavalent vaccines. Further studies are needed regarding the 2 + 1 schedule. Apnea represents a nonspecific stress response in PIs, thus those hospitalized at 2 months should have cardio-respiratory monitoring after their first vaccination.

Randomized Controlled Trial on the Effects of Morning versus Evening Primary Vaccination on Episodes of Hypoxemia and Bradycardia in Very Preterm Infants

BACKGROUND

Hypoxemia and bradycardia occur frequently in preterm infants, but are incompletely understood. They are more prevalent during infections and following immunization. Data on adults suggested an increased immune response if subjects slept following vaccination, suggesting an interaction between circadian rhythm and the immune system. Whether this holds true for preterm infants with their less well-established circadian rhythm is unclear.

OBJECTIVE

Do infants born at 26-30 weeks' gestation and having received their first routine hexavalent vaccination in the morning have a lower cardiorespiratory event rate (CER) after vaccination than those receiving it in the evening?

METHODS

Twenty-six infants were randomized to an evening versus morning vaccination group in a pilot and main study with 10 and 16 participants, respectively. Pulse oximeter saturation, actigraphy, and rectal temperature were obtained for 24 h before and after vaccination. Blood samples for vaccination titers were taken before vaccination and during a follow-up examination in our outpatient clinic; another blood sample was taken 24 h after vaccination to determine inflammatory markers.

RESULTS

Vaccination led to an increase in CER in both groups, but there was no difference in CER between the morning and evening groups. Vaccination titers for Bordetella pertussis were increased in both groups, with no difference in inflammatory markers 24 h after vaccination. Body temperature increased in both groups after vaccination. Participants in the evening group slept longer after vaccination.

CONCLUSIONS

We did not identify a difference in CER between morning and evening vaccination but could confirm increased body temperatures and vaccination titers following vaccination.

Vaccination timeliness in preterm infants: An integrative review of the literature

AIMS AND OBJECTIVES

To take a systematic approach to reviewing the scientific literature examining the timeliness of vaccination in preterm infants and to identify any factors associated with timeliness.

BACKGROUND

Preterm infants are vulnerable to infection and guidance advocates they are vaccinated in accordance with their full-term peers. Vaccination is well tolerated and protective immune responses are observed, yet some early enquiries suggest that preterm infants experience unwarranted delays. The recent surge in pertussis cases and the increase in vaccinations administered make this a topic requiring further exploration.

DESIGN

An integrative review of the empirical literature.

METHODS

Studies were identified following a search of Medline, Academic Search Premier, Cochrane Database of Systematic Reviews and the Cumulative Index to Nursing and Allied Health Literature. The review methods used were influenced by a narrative synthesis approach. The retrieval of papers adhered to recognised reporting standards.

RESULTS

Fourteen studies were identified, which indicated that infants with the lowest gestational ages and birthweights experience the greatest delays. Vaccination timeliness is influenced by hospitalisation and increased postdischarge follow-up. There was a lack of consensus to indicate that parental socio-economic status and level of education were indicators for a delay. The studies propose that many delays are unjustified and not according to genuine contraindications.

CONCLUSION

This review indicates that preterm infants are not vaccinated in a timely manner. Those involved in vaccinating preterm infants must be informed of the genuine contraindications to avoid unnecessary delays putting preterm infants at an increased risk of infection.

RELEVANCE TO CLINICAL PRACTICE

Care providers should acknowledge the risk of a delay in preterm infants and actively promote vaccination in this population. Regular training should help to negate the occurrence of inappropriate delays, and careful discharge planning is needed to ensure that preterm infants are vaccinated on time.

Adverse Events After Routine Immunization of Extremely Low-Birth-Weight Infants

IMPORTANCE

Immunization of extremely low-birth-weight (ELBW) infants in the neonatal intensive care unit (NICU) is associated with adverse events, including fever and apnea or bradycardia, in the immediate postimmunization period. These adverse events present a diagnostic dilemma for physicians, leading to the potential for immunization delay and sepsis evaluations.

OBJECTIVE

To compare the incidence of sepsis evaluations, need for increased respiratory support, intubation, seizures, and death among immunized ELBW infants in the 3 days before and after immunization.

DESIGN, SETTING, AND PARTICIPANTS

In this multicenter retrospective cohort study, we studied 13,926 ELBW infants born at 28 weeks' gestation or less who were discharged from January 1, 2007, through December 31, 2012, from 348 NICUs managed by the Pediatrix Medical Group.

EXPOSURES

At least one immunization between the ages of 53 and 110 days.

MAIN OUTCOMES AND MEASURES

Incidence of sepsis evaluations, need for increased respiratory support, intubation, seizures, and death.

RESULTS

Most of the 13,926 infants (91.2%) received 3 or more immunizations. The incidence of sepsis evaluations increased from 5.4 per 1000 patient-days in the preimmunization period to 19.3 per 1000 patient-days in the postimmunization period (adjusted rate ratio [ARR], 3.7; 95% CI, 3.2-4.4). The need for increased respiratory support increased from 6.6 per 1000 patient-days in the preimmunization period to 14.0 per 1000 patient-days in the postimmunization period (ARR, 2.1; 95% CI, 1.9-2.5), and intubation increased from 2.0 per 1000 patient-days to 3.6 per 1000 patient-days (ARR, 1.7; 95% CI, 1.3-2.2). The postimmunization incidence of adverse events was similar across immunization types, including combination vaccines when compared with single-dose vaccines. Infants who were born at 23 to 24 weeks' gestation had a higher risk of sepsis evaluation and intubation after immunization. A prior history of sepsis was associated with higher risk of sepsis evaluation after immunization.

CONCLUSIONS AND RELEVANCE

All ELBW infants in the NICU had an increased incidence of sepsis evaluations and increased respiratory support and intubation after routine immunization. Our findings provide no evidence to suggest that physicians should not use combination vaccines in ELBW infants. Further studies are needed to determine whether timing or spacing of immunization administrations confers risk for the developing adverse events and whether a prior history of sepsis confers risk for an altered immune response in ELBW infants.