Pulmonary hypertension in late onset neonatal sepsis using functional echocardiography: a prospective study

Cardiopulmonary Physiology of Hypoxemic Respiratory Failure Among Preterm Infants with Septic Shock

OBJECTIVE

To examine cardiopulmonary physiological alterations associated with hypoxemic respiratory failure (HRF; fraction of inspired oxygen ≥0.60) among preterm neonates requiring vasopressors/inotropes during sepsis (septic shock).

STUDY DESIGN

We conducted a retrospective cohort study from 2015 through 2022 at a tertiary neonatal intensive care unit. Neonates <34 weeks gestational age who had septic shock and underwent a comprehensive targeted neonatal echocardiography (TNE) ≤72 hours of sepsis onset were included. TNE findings of patients with shock and HRF were compared with those with shock without HRF. Indices of pulmonary vascular resistance (PVR), right ventricular (RV) and left ventricular (LV) systolic and diastolic function, measured using conventional, tissue Doppler imaging and speckle-tracking echocardiography, were examined.

RESULTS

Of 52 included infants with septic shock, 19 (37%) also had HRF. Baseline characteristics were similar. On TNE, although the HRF group more frequently had bidirectional/right-to-left flow across the patent ductus arteriosus (67% vs 33%; P = .08), all indices of PVR and RV function were similar. However, the HRF group demonstrated reduced LV systolic function (ejection fraction, 51.8% ± 12.3% vs 62.6% ± 13.0%; global peak systolic longitudinal strain -15.2% ± 4.5% vs -18.6% ± 4.5%), diastolic function (early [2.3 ± 1.0/s vs 3.6 ± 1.2/s]) and late (2.4/s [IQR, 1.9-2.6/s] vs 2.8/s [2.3-3.5/s] diastolic strain rate), and higher frequency of LV output <150 mL/min/kg (44% vs 12%) (all P < .05).

CONCLUSIONS

Acute HRF occurring in preterm neonates with septic shock is associated with alterations in TNE measures of LV function, and not PVR or RV function. Future studies should evaluate the impact of supporting LV function in these patients.

A pilot randomized controlled trial comparing noradrenaline and adrenaline as a first-line vasopressor for fluid-refractory septic shock in neonates

Background and study design

Limited data exists on noradrenaline therapy in neonatal septic shock. We compared the efficacy of noradrenaline with adrenaline in neonatal septic shock. This single center, open label, pilot randomized controlled trial included neonates with clinical evidence of sepsis and shock.

Study outcomes

Primary outcomes were: 1) resolution of shock one hour after treatment, and 2) mortality during hospital stay. Secondary outcomes included: need for additional vasopressors; hemodynamic stability without further administration of vasopressors for ≥2 h; changes in blood pressure and heart rate after 1 h of vasopressor treatment; and morbidities during the hospital stay.

Results

Of 65 eligible neonates, 42 were randomized (21 each in adrenaline and noradrenaline treatment arms) between August 2020 and January 2022, at level III neonatal intensive care unit (NICU) of Bharati Vidyapeeth Deemed University Medical College and Hospital (BVDUMCH). The mean (SD) gestational age and mean (SD) birth weight were 36.1(4.2) weeks and 1.8 (0.2) kilograms birth weight for noradrenaline and 36.9 (4.1) weeks and 1.7 (0.7) kilograms for adrenaline. Shock resolved within 1 h of vasopressor therapy in 76.2% neonates in the noradrenaline arm and 61.9% in adrenaline arm (p value-0.53). Mortality during hospital stay was 28.6% (6/21) in noradrenaline group and 33.3% (7/21) in adrenaline group (p value- 0.58). Additional vasopressors were required in 23.8% neonates of the noradrenaline group compared to 38.1% neonates in adrenaline arm (p value-0.53). Median (SD) duration of intensive care stay was 6 (SD) days in the noradrenaline group and 10 (SD) days in the adrenaline group (p value-0.045).

Conclusion

Among neonates with septic shock, the efficacy of noradrenaline was comparable to adrenaline in resolving septic shock after one hour of infusion and on the mortality during hospital stay.

Clinical Trial Registration

https://ctri.nic.in/Clinicaltrials/pmaindet2.php?EncHid=NDI2NTc=&Enc=&userName=noradrenaline, Clinical Trials Registry - India with identifier CTRI/2020/08/027185 (17/08/2020).

Assessment of hemodynamic dysfunction in septic newborns by functional echocardiography: a systematic review

BACKGROUND

Neonatal sepsis remains a leading cause of mortality in neonatal units. Neonatologist-performed echocardiography (NPE) offers the potential for early detection of sepsis-associated cardiovascular dysfunction. This review examines available echocardiographic findings in septic neonates.

METHODS

Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we systematically reviewed prospective observational, cross-sectional, case control, and cohort studies on septic newborns with echocardiographic assessments from PubMed, Scopus and Embase. Quality assessment employed the Newcastle-Ottawa Scale, with results analyzed descriptively.

RESULTS

From an initial pool of 1663 papers, 12 studies met inclusion criteria after relevance screening and eliminating duplicates/excluded studies. The review encompassed 438 septic newborns and 232 controls. Septic neonates exhibited either increased risk of pulmonary hypertension or left ventricular diastolic dysfunction, and a warm shock physiology characterized by higher cardiac outputs.

DISCUSSION

The included studies exhibited heterogeneity in sepsis definitions, sepsis severity scores, echocardiographic evaluations, and demographic data of newborns. Limited sample sizes compromised analytical interpretability. Nonetheless, this work establishes a foundation for future high-quality echocardiographic studies.

CONCLUSION

Our review confirms that septic neonates show significant hemodynamic changes that can be identified using NPE. These findings underscore the need for wider NPE use to tailor hemodynamics-based strategies within this population.

IMPACT

1. Our study emphasizes the value of neonatologist-performed echocardiography (NPE) as a feasible tool for identifying significant hemodynamic changes in septic neonates. 2. Our study underscores the importance of standardized echocardiographic protocols and frequent monitoring of cardiac function in septic neonates. 3. The impact of the study lies in its potential to increase researchers' awareness for the need for more high-quality echocardiographic data in future studies. By promoting wider use of NPE, neonatologists can more accurately assess the hemodynamic status of septic newborns and tailor treatment approaches, potentially improving patient outcomes.

Neonatal sepsis and cardiovascular dysfunction I: mechanisms and pathophysiology

The highest incidence of sepsis across all age groups occurs in neonates leading to substantial mortality and morbidity. Cardiovascular dysfunction frequently complicates neonatal sepsis including biventricular systolic and/or diastolic dysfunction, vasoregulatory failure, and pulmonary arterial hypertension. The haemodynamic response in neonatal sepsis can be hyperdynamic or hypodynamic and the underlying pathophysiological mechanisms are heterogeneous. The diagnosis and definition of both neonatal sepsis and cardiovascular dysfunction complicating neonatal sepsis are challenging and not consensus-based. Future developments in neonatal sepsis management will be facilitated by common definitions and datasets especially in neonatal cardiovascular optimisation. IMPACT: Cardiovascular dysfunction is common in neonatal sepsis but there is no consensus-based definition, making calculating the incidence and designing clinical trials challenging. Neonatal cardiovascular dysfunction is related to the inflammatory response, which can directly target myocyte function and systemic haemodynamics.

Neonatal Sepsis Caused by Streptococcus gallolyticus Complicated with Pulmonary Hypertension: A Case-Report and a Systematic Literature Review

Streptococcus gallolyticus (S. gallolyticus) has been linked to the development of infections in adults; however, in neonates S. gallolyticus sepsis is very rare and resembles Group B Streptococcal infections. In this case report, we present the case of a full-term neonate who developed early-onset sepsis due to S. gallolyticus. A systematic review of the literature was also conducted. The neonate had good APGAR scores at 1' and 5'. At 5 h postnatally, the neonate developed poor feeding and respiratory distress. She received oxygen in a head box, and a complete blood count and biochemistry, blood, CSF and body surface cultures were obtained. Empiric intravenous antibiotics (ampicillin and tobramycin) were initiated, and she was transferred to a tertiary NICU for further treatment. The neonate was mechanically ventilated and received dopamine and colloid fluids for circulatory support. A cardiology consultation revealed pulmonary hypertension on day one. S. gallolyticus was isolated in the blood culture. Central nervous system ultrasonography, brainstem auditory evoked potentials, and a second cardiology evaluation were normal on day three. Clinical and laboratory improvement was noted on day three, and the baby was discharged after a 12-day hospitalization. Follow-up visits were scheduled for reevaluation.

The role of bedside functional echocardiography in the assessment and management of pulmonary hypertension

Pulmonary hypertension is an emergency in neonatal intensive care units with high morbidity and mortality. Its timely assessment and management is crucial for intact survival. Over the last couple of decades, there have been significant advances in management and techniques, which have resulted in improved survival. The use of neonatologist-performed echocardiography (NPE) is now increasingly utilized on neonatal intensive care units to understand the pathophysiology of the disease and to direct the treatment to the underlying cause. Its use is now established not only in cases of congenital diaphragmatic hernia and in the newborn with refractory hypoxemia, but also in other conditions such as bronchopulmonary dysplasia and the premature infant with difficulty in oxygenation. The use of NPE, however, requires the availability of trained personnel, equipment, and a close working relationship with pediatric cardiology.

Hemodynamic dysfunction in neonatal sepsis

Cardiovascular disturbances are a frequent occurrence in neonatal sepsis. Preterm and term infants are particularly vulnerable due to the unique features of their cardiovascular function and reserve, compared to older children and adults. The clinical manifestations of neonatal sepsis are a product of the variable inflammatory pathways involved (warm vs. cold shock physiology), developmental state of the cardiovascular system, and hormonal responses. Targeted neonatal echocardiography has played an important role in advancing our knowledge, may help delineate specific hemodynamic phenotypes in real-time, and supports an individualized physiology-based management of sepsis-associated cardiovascular dysfunction. IMPACT: Cardiovascular dysfunction is a common sequela of sepsis. This review aims to highlight the pathophysiological mechanisms involved in hemodynamic disturbance in neonatal sepsis, provide insights from targeted neonatal echocardiography-based clinical studies, and suggest its potential incorporation in day-to-day management.