Trends in pharmacotherapy for neonatal hypotension

Comparative efficacy of volume expansion, inotropes and vasopressors in preterm neonates with probable transitional circulatory instability in the first week of life: a systematic review and network meta-analysis

BACKGROUND

There exists limited agreement on the recommendations for the treatment of transitional circulatory instability (TCI) in preterm neonates OBJECTIVE: To compare the efficacy of various interventions used to treat TCI METHODS: Medline and Embase were searched from inception to 21st July 2023. Two authors extracted the data independently. A Bayesian random effects network meta-analysis was used. Recommendations were formulated using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) framework.

INTERVENTIONS

Dopamine, dobutamine, epinephrine, hydrocortisone, vasopressin, milrinone, volume and placebo.

MAIN OUTCOME MEASURES

Mortality, major brain injury (MBI) (intraventricular haemorrhage > grade 2 or cystic periventricular leukomalacia), necrotising enterocolitis (NEC) ≥stage 2 and treatment response (as defined by the author).

RESULTS

15 Randomized Controlled Trials (RCTs) were included from the 1365 titles and abstracts screened. Clinical benefit or harm could not be ruled out for the critical outcome of mortality. For the outcome of MBI, epinephrine possibly decreased the risk when compared to dobutamine and milrinone (very low certainty). Epinephrine was possibly associated with a lesser risk of NEC when compared with dopamine, dobutamine, hydrocortisone and milrinone (very low certainty). Dopamine was possibly associated with a lesser risk of NEC when compared with dobutamine (very low certainty). Vasopressin possibly decreased the risk of NEC compared with dopamine, dobutamine, hydrocortisone and milrinone (very low certainty). Clinical benefit or harm could not be ruled out for the outcome response to treatment.

CONCLUSIONS

Epinephrine may be used as the first-line drug in preterm neonates with TCI, the evidence certainty being very low. We suggest future trials evaluating the management of TCI with an emphasis on objective criteria to define it.

An Update on Pharmacologic Management of Neonatal Hypotension: When, Why, and Which Medication

Anti-hypotensive treatment, which includes dopamine, dobutamine, epinephrine, norepinephrine, milrinone, vasopressin, terlipressin, levosimendan, and glucocorticoids, is a long-established intervention in neonates with arterial hypotension (AH). However, there are still gaps in knowledge and issues that need clarification. The main questions and challenges that neonatologists face relate to the reference ranges of arterial blood pressure in presumably healthy neonates in relation to gestational and postnatal age; the arterial blood pressure level that potentially affects perfusion of critical organs; the incorporation of targeted echocardiography and near-infrared spectroscopy for assessing heart function and cerebral perfusion in clinical practice; the indication, timing, and choice of medication for each individual patient; the limited randomized clinical trials in neonates with sometimes conflicting results; and the sparse data regarding the potential effect of early hypotension or anti-hypotensive medications on long-term neurodevelopment. In this review, after a short review of AH definitions used in neonates and existing data on pathophysiology of AH, we discuss currently available data on pharmacokinetic and hemodynamic effects, as well as the effectiveness and safety of anti-hypotensive medications in neonates. In addition, data on the comparisons between anti-hypotensive medications and current suggestions for the main indications of each medication are discussed.

A Framework for Neonatal Prematurity Information System Development Based on a Systematic Review on Current Registries: An Original Research

Background

Registries are regarded as a just valuable fount of data on determining neonates suffering prematurity or low birth weight (LBW), ameliorating provided care, and developing studies.

Objective

This study aimed to probe the studies, including premature infants' registries, adapt the needed minimum data set, and provide an offered framework for premature infants' registries.

Material and Methods

For this descriptive study, electronic databases including PubMed, Scopus, Web of Science, ProQuest, and Embase/Medline were searched. In addition, a review of gray literature was undertaken to identify relevant studies in English on current registries and databases. Screening of titles, abstracts, and full texts was conducted independently based on PRISMA guidelines. The basic registry information, scope, registry type, data source, the purpose of the registry, and important variables were extracted and analyzed.

Results

Fifty-six papers were qualified and contained in the process that presented 51 systems and databases linked in prematurity at the popular and government levels in 34 countries from 1963 to 2017. As a central model of the information management system and knowledge management, a prematurity registry framework was offered based on data, information, and knowledge structure.

Conclusion

To the best of our knowledge, this is a comprehensive study that has systematically reviewed prematurity-related registries. Since there are international standards to develop new registries, the proposed framework in this article can be beneficial too. This framework is essential not only to facilitate the prematurity registry design but also to help the collection of high-value clinical data necessary for the acquisition of better clinical knowledge.

Corticosteroid use in neonatal hypotension: A survey of Canadian neonatologists

OBJECTIVE

To assess prescribing practices and perspectives regarding the use of corticosteroids in the management of neonatal hypotension.

METHODS

Cross-sectional questionnaire-based electronic survey of neonatologists (n = 206) practicing at tertiary neonatal intensive care units across 30 academic centres in Canada.

RESULTS

The overall response rate was 33% (72/206), with a completion rate was 94%. Most (48/72, 64%) worked in a unit that covered both inborn and outborn infants, and 53% (37/70) worked in units with >100 very low birth weight infants admitted annually. Among the 72 respondents, 39% use a loading dose, of whom most (57%) use 2 mg/kg. Dosing ranges were variable, most using either 0.5 mg/kg or 1 mg/kg, q6h. Among the 56% (40/72) of neonatologists who reported measuring cortisol before initiation of hydrocortisone, cut-offs for initiation of hydrocortisone varied from <100 to <500 nmol/L, most of whom (48%) used <100 nmol/L. Of 71 respondents, 92% (65) indicated that a randomized control trial examining the use of corticosteroids in neonatal hypotension is needed, of whom 52% (37) indicated that the intervention group should receiving hydrocortisone after one vasopressor/inotrope.

CONCLUSIONS

This survey provides insight into the prescribing practices of tertiary neonatologists with regards to the use of corticosteroids in neonatal hypotension. While corticosteroids are frequently prescribed, there is variability in the indication, dosing, and duration of corticosteroid use. The findings from this survey can be used to inform further research, including a clinical trial, regarding the practice in the management of neonatal hypotension.

Evidence-Based Guidelines for Acute Stabilization and Management of Neonates with Persistent Pulmonary Hypertension of the Newborn

Persistent pulmonary hypertension of the newborn, or PPHN, represents a challenging condition associated with high morbidity and mortality. Management is complicated by complex pathophysiology and limited neonatal specific evidence-based literature, leading to a lack of universal contemporary clinical guidelines for the care of these patients. To address this need and to provide consistent high-quality clinical care for this challenging population in our neonatal intensive care unit, we sought to develop a comprehensive clinical guideline for the acute stabilization and management of neonates with PPHN. Utilizing cross-disciplinary expertise and incorporating an extensive literature search to guide best practice, we present an approachable, pragmatic, and clinically relevant guide for the bedside management of acute PPHN. KEY POINTS: · PPHN is associated with several unique diagnoses; the associated pathophysiology is different for each unique diagnosis.. · PPHN is a challenging, dynamic, and labile process for which optimal care requires frequent reassessment.. · Key management goals are adequate tissue oxygen delivery, avoiding harm..

Use of norepinephrine in preterm neonates with dopamine-resistant shock: a retrospective single-centre cross-sectional study

BACKGROUND

Norepinephrine (NE) is recommended for children and full-term neonates (born at >37 gestational weeks) with septic shock. Meanwhile, data on the effectiveness of NE in preterm neonates are still limited. This study aimed to evaluate the clinical efficacy of NE in preterm neonates with dopamine-resistant shock compared with that in full-term neonates.

METHODS

This was a single-centre, retrospective (January 2010-December 2020) cohort study of neonates with persistent shock despite adequate fluid resuscitation and dopamine or dobutamine administration at ≥10 μg/kg/min. Medical records of neonates treated with NE were retrospectively reviewed to collect respiratory and haemodynamic parameters and results of arterial blood gas (ABG) tests before and 8 hours after NE infusion. The effectiveness of NE was assessed using changes in clinical parameters and multiple regression models for mortality among subgroups of preterm and full-term neonates.

RESULTS

Ninety-two neonates (76% preterm) who received NE infusion were included in the study. NE infusion was started after a median of 7 hours (IQR 2-19 hours) after shock onset. Among the preterm neonates, the maximum dose of NE infusion was 0.5 (IQR 0.3-1.0) µg/kg/min with a median duration of 45 (IQR 24.0-84.5) hours. Haemodynamic dysfunction was ameliorated with increased blood pressure, decreased heart rate and improved ABG results. Preterm neonates with septic shock tended to have a reduced response to NE; however, preterm neonates with persistent pulmonary hypertension of the newborn tended to have a better response. Thirty-four (37%) neonates died in our cohort. The timing, dose and duration of NE use were not associated with neonatal mortality.

CONCLUSIONS

Although using NE effectively improves clinical parameters in preterm neonates with dopamine-resistant shock, our study is underpowered to identify the association between NE infusion and mortality in preterm neonates with dopamine-resistant shock.

Vein of Galen aneurysmal malformation: rationalizing medical management of neonatal heart failure

Neonates who present in high output heart failure secondary to vein of Galen aneurysmal malformation can be difficult to manage medically due to the complex physiology that results from the large shunt through the malformation. Though the cardiac function is often normal, right ventricular dilation, severe pulmonary hypertension, and systemic steal can result in inadequate organ perfusion and shock. This report recommends medical management for stabilization of neonates prior to definitive management with endovascular embolization. IMPACT: Vein of Galen aneurysmal malformation (VGAM) is a rare intracranial arteriovenous malformation, which can present in the neonatal period with high output heart failure. Heart failure secondary to VGAM is often difficult to manage and is associated with high mortality and morbidity. Despite optimal medical management, many patients require urgent endovascular embolization for stabilization of their heart failure. This report offers discrete recommendations that can be used by clinicians as guidelines for the medical management of heart failure in newborns with VGAM.

Efficacy and Safety of Vasopressin and Terlipressin in Preterm Neonates: A Systematic Review

INTRODUCTION

The use of arginine vasopressin (AVP) and terlipressin to treat hypotension in preterm neonates is increasing. Our aim was to review the available evidence on the efficacy and safety of AVP and terlipressin for use in preterm neonates.

METHODS

MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, Web of Science, and Google Scholar from inception to September 2021 were searched for studies of AVP and terlipressin in the treatment of hypotension of any cause in preterm neonates. Primary outcomes were improvement in end-organ perfusion and mortality. The risk of bias assessment and certainty of the evidence were performed using appropriate tools.

RESULTS

Fifteen studies describing the use of AVP (n = 12) or terlipressin (n = 3) among 148 preterm neonates were included. Certainly, the available evidence for the primary outcome of end-organ perfusion rated as very low. AVP or terlipressin were used to treat 144 and 4 neonates, respectively. Improvement in markers of end-organ perfusion was reported in 143 (99%) neonates treated with AVP and 3 (75%) treated with terlipressin. The mortality rate was 41% (n = 59) and 50% (n = 2) for neonates who received AVP and terlipressin, respectively. Hyponatremia was the most frequently reported adverse event (n = 37, 25%).

CONCLUSION

AVP and terlipressin may improve measured blood pressure values and possibly end-organ perfusion among neonates with refractory hypotension. However, the efficacy-safety balance of these drugs should be assessed on an individual basis and as per the underlying cause. Studies on the optimal dosing, efficacy, and safety of AVP and terlipressin in preterm neonates with variable underlying conditions are critically needed.

Blood pressure values and hypotension management in extremely preterm infants: a multi-center study

OBJECTIVE

To describe high/low daily blood pressures (BP) and variability in BP management with vasoactive infusions (VI) and/or hydrocortisone (HC) in extremely preterm infants.

STUDY DESIGN

Analysis of data from 24-27 weeks' gestation infants in the Preterm Erythropoietin Neuroprotection (PENUT) Trial. Daily high/low BPs, the use of VI and/or HC, and adverse outcomes were compared descriptively and using regression models.

RESULTS

936 infants were included; 64% untreated, 20% VI, 3% HC, and 13% VI + HC. BP ranges are described for the 602 untreated infants. Considerable inter- and intra-center variability was demonstrated in the rate of VI and/or HC use and the lowest BP on the day of VI or HC initiation.

CONCLUSIONS

Despite published expert opinion guidance regarding BP management in extremely preterm infants, our results suggest a continued lack of consensus result in both inter- and intra-center variability in practice. Well-designed studies in the field are urgently needed.

Recognition and Management of Cardiovascular Insufficiency in the Very Low Birth Weight Newborn

The measurement of blood pressure in the very low birth weight newborn infant is not simple and may be erroneous because of numerous factors. Assessment of cardiovascular insufficiency in this population should be based on multiple parameters and not only on numeric blood pressure readings. The decision to treat cardiovascular insufficiency should be made after considering the potential complications of such treatment. There are numerous potential strategies to avoid or mitigate hypoperfusion states in the very low birth weight infant.

Effect of Vasopressin on Systemic and Pulmonary Hemodynamics in Neonates

OBJECTIVE

Despite its increasing use in neonates, the literature on the use of vasopressin (VP) in neonates is limited. The aim of this study is to evaluate the systemic and pulmonary effects of VP in neonates and to assess its safety among them.

STUDY DESIGN

This retrospective study enrolled all neonates in two level III neonatal intensive care units in Winnipeg, Manitoba, who had received VP therapy between 2011 and 2016. Infants with congenital malformations/chromosomal disorders were excluded. The changes in cardiovascular and pulmonary parameters were collected from patient charts. The primary outcome was the mean blood pressure (MBP) post-VP initiation. Secondary outcomes included systolic blood pressure (SBP) and diastolic blood pressure (DBP), vasoactive inotropic score (VIS), pH, urine output, lactate, base deficit (BD), mean airway pressure (MAP), and oxygen requirement.

RESULTS

A total of 33 episodes from 26 neonates were analyzed. The postnatal age at VP initiation was 14 days (interquartile range [IQR]: 4-25), and the median starting dose was 0.3 mU/kg/min (IQR: 0.2-0.5). MBP improved significantly after VP initiation from 28 to 39 mm Hg 24 hours after VP initiation (p < 0.001). Similar changes are observed with SBP and DBP. VIS declined from 15 to 6 at 24 hours, while pH, lactate, BD, and oxygen requirement improved significantly. While urine output marginally improved, there were no changes to MAP 24 hours post-VP initiation. Hyponatremia was observed in 21 episodes (64%) and severe hyponatremia in 7 episodes (33%).

CONCLUSION

VP appears to be a promising rescue therapy in catecholamine resistant shock or refractory pulmonary hypertension in neonates.

Vasoactive medications in extremely low gestational age neonates during the first postnatal week

OBJECTIVE

The management of early hypotension in extremely low gestational age neonates (ELGANs) varies greatly between centers. The objective of this study was to provide updated data on the use of vasoactive medications in ELGANs during the first postnatal week.

STUDY DESIGN

We identified ELGANs (22-27 weeks gestational age) cared for at Pediatrix neonatal intensive care units from 2009 to 2018. We evaluated the frequency of exposure to vasoactive medications by gestational age, and compared use of vasoactive medications between two epochs (2009-2013 and 2014-2018).

RESULTS

A total of 10,070/34,234 (29%) ELGANs received ≥1 vasoactive medication. Dopamine was the most frequently used vasoactive medication. The majority (83%) of treated ELGANs initiated therapy on postnatal days 0-1. Overall use of vasoactive medications was slightly lower in 2014-2018 than 2009-2013 (28 vs 31%, p < 0.001).

CONCLUSION

A substantial proportion of ELGANs were exposed to vasoactive medications during the first postnatal week.

Influence of innate immune activation on endocrine and metabolic pathways in infancy

Prematurity is the leading cause of neonatal morbidity and mortality worldwide. Premature infants often require extended hospital stays, with increased risk of developing infection compared with term infants. A picture is emerging of wide-ranging deleterious consequences resulting from innate immune system activation in the newborn infant. Those who survive infection have been exposed to a stimulus that can impose long-lasting alterations into later life. In this review, we discuss sepsis-driven alterations in integrated neuroendocrine and metabolic pathways and highlight current knowledge gaps in respect of neonatal sepsis. We review established biomarkers for sepsis and extend the discussion to examine emerging findings from human and animal models of neonatal sepsis that propose novel biomarkers for early identification of sepsis. Future research in this area is required to establish a greater understanding of the distinct neonatal signature of early and late-stage infection, to improve diagnosis, curtail inappropriate antibiotic use, and promote precision medicine through a biomarker-guided empirical and adjunctive treatment approach for neonatal sepsis. There is an unmet clinical need to decrease sepsis-induced morbidity in neonates, to limit and prevent adverse consequences in later life and decrease mortality.

Hemodynamic support of the micropreemie: Should hydrocortisone never be left out?

Hemodynamic support for a micropreemie is critically important for preventing mortality and morbidity. An essential consideration in hemodynamic support is insufficient transition from fetal to neonatal circulation and inadequate cortisol production. The first 72 h of life are the most critical, especially when myocardial function is immature and impaired. Therefore, there is a need to determine and adjust preload, myocardial contractility, and afterload appropriately using repeated functional echocardiography. In addition, if myocardial function is not responsive to these attempts at hemodynamic management, hydrocortisone must be used to minimize the suboptimal perfusion burden. Fetal cortisol production is supported by a supply of progesterone from the placenta, and postnatally, adrenal cortisol production in the extremely preterm infant may be inadequate if the infant is placed under excessive stress. This leads to relative adrenal insufficiency which may last for up to several weeks after birth and lead to late-onset circulatory collapse, necessitating treatment with physiological doses of hydrocortisone.

Intensity of Vasopressor Therapy and In-Hospital Mortality for Infants and Children: An Opportunity for Counseling Families

CONTEXT

Most pediatric deaths occur in an intensive care unit, and treatment specific predictors of mortality could help clinicians and families make informed decisions.

OBJECTIVE

To investigate whether the intensity of vasopressor therapy for pediatric patients, regardless of diagnosis, predicts in-hospital mortality.

METHODS

Single-center, retrospective medical chart review of children aged 0-17 who were admitted between 2005 and 2015 at a pediatric tertiary care center in the U.S. and received any vasopressor medication-dopamine, dobutamine, epinephrine, vasopressin, norepinephrine, or hydrocortisone.

RESULTS

During the 10-year period, 1654 patients received at least one vasopressor medication during a hospitalization. Median age at the time of hospitalization was three months, and the median duration of hospitalization was 23 days; 8% of patients had two to five hospitalizations in which they received vasopressors. There were 176 total patients who died while receiving vasopressors; most (93%) died during their first hospitalization. The most common diagnosis was sepsis (34%), followed by congenital heart disease (17%). Dopamine was the most commonly prescribed first-line vasopressor (70%), and hydrocortisone was the most commonly prescribed second-line vasopressor (49%) for all pediatric patients. The incidence of mortality rose sequentially with escalating vasopressor support, increasing from under 10% with the first vasopressor to 48% at the maximum number of agents. The odds of death almost doubled with the addition of each new vasopressor.

CONCLUSIONS

The intensity of vasopressor therapy for pediatric patients, regardless of diagnosis, is associated with in-hospital mortality; vasopressor escalation should trigger intensive palliative care supports.

Recognition and management of neonatal hemodynamic compromise

Hemodynamic compromise of the neonate can occur in various clinical situations, including but not limited to maladaptation during the early transitional period, sepsis, congenital heart anomalies, hemodynamically significant patent ductus arteriosus, persistent pulmonary hypertension of the newborn, systemic inflammatory diseases such as necrotizing enterocolitis, and dehydration. Despite the handful of advances in neonatal care through ground-breaking clinical trials, the management of neonatal shock is often dependent on the bedside clinician's experience and training without the aid of high-level evidence. However, the recognition for the importance of comprehensive and serial hemodynamic assessment is growing. There is now a wealth of literature investigating the use of functional echocardiography, near-infrared spectroscopy, and noninvasive impedance-based cardiometry to complement common bedside hemodynamic measures such as blood pressure and heart rate measurement. In this review article, the pathophysiology of neonatal hemodynamic compromise is outlined, and concomitant best-evidence management for hemodynamic compromise in the neonate is proposed.

Efficacy of Low-Dose Epinephrine Continuous Infusion in Neonatal Intensive Care Unit Patients

OBJECTIVES

Although epinephrine is used in the neonatal intensive care unit, few data exist on efficacy of doses <0.05 mcg/kg/min. This study evaluates the efficacy and safety of low-dose epinephrine continuous infusion at doses <0.05 mcg/kg/min in infants.

METHODS

Single-center, retrospective review of hypotensive infants from 2011-2018. Charts were reviewed for initial and maximum epinephrine doses, additional vasoactive agents, short-term efficacy, and adverse effects. The primary outcome was percentage of patients initiated on low-dose epinephrine whose dose did not require titration to ≥0.05 mcg/kg/min.

RESULTS

A total of 115 patients met study criteria with 131 distinct occurrences of low-dose epinephrine initiation. Most patients were unresponsive to other vasopressors at the time of epinephrine initiation. The median (IQR) starting dose of low-dose epinephrine was 0.01 (0.01-0.04) mcg/kg/min and median (IQR) maximum dose was 0.04 (0.02-0.08) mcg/kg/min. Fifty-five percent were responders. Patients in this cohort demonstrated significant improvement of blood pressure and urine output (p < 0.001) without adverse effects.

CONCLUSIONS

Low-dose epinephrine infusion may be considered as an alternative treatment to standard starting doses in hypotensive neonatal intensive care unit patients.

Efficacy and safety of vasopressin and terlipressin in preterm neonates: a protocol for a systematic review

BACKGROUND

The use of vasoactive agents like arginine vasopressin (AVP) and terlipressin to treat hypotension or persistent pulmonary hypertension in critically ill preterm neonates is increasing. Therefore, a systematic review of the available data on dosing, efficacy and safety of AVP and terlipressin in this patient population appears beneficial.

METHODS

We will conduct a systematic review of the available evidence on the use of AVP and terlipressin for the treatment of hypotension or persistent pulmonary hypertension in preterm neonates. We will search Ovid MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, Web of Science and Google Scholar from inception to March 2021. Two reviewers will independently screen titles and abstracts, review the full text of eligible studies, extract data, assess the risk of bias and judge the certainty of the evidence. Our primary outcome will be an (1) improvement of end-organ perfusion after initiation of AVP or terlipressin and (2) mortality prior to discharge. Our secondary outcomes will include (1) major neurosensory abnormality and (2) the occurrence of adverse events.

DISCUSSION

The currently available evidence on the efficacy and safety of AVP and terlipressin in preterm neonates is limited. Yet, evidence on the pharmacology of these drugs and the pathophysiology of vasoplegic shock support the biological plausibility for their clinical effectiveness in this population. Therefore, we aim to address this gap concerning the use of vasopressin and terlipressin among critically ill preterm neonates.

TRIAL REGISTRATION

This protocol has been submitted for registration to the international database of prospectively registered systematic reviews (PROSPERO, awaiting registration number).

Cardiovascular Pharmacological Support Among Preterm Infants in Chinese Referral Center Neonatal Intensive Care Units

Objective: To describe cardiovascular pharmacological support in infants born at <34 weeks' gestation within the first postnatal week in Chinese neonatal intensive care units (NICUs). Design: A secondary analysis of data from a multicenter randomized controlled study (REIN-EPIQ). A questionnaire regarding cardiovascular support practices was also completed by all participating NICUs. Setting: Twenty-five tertiary hospitals from 19 provinces in China. Patients: All infants born at <34 weeks' gestation and admitted to participating NICUs within the first postnatal week from May 2015 to April 2018 were included. Infants who were discharged against medical advice were excluded. Measures and Main Results: Among the 26,212 preterm infants <34 weeks, 16.1% received cardiovascular pharmacological support. The use rates increased with decreasing gestational age and birth weight, with 32.5% among infants <28 weeks and 35.9% among infants <1,000 g. Cardiovascular pharmacological support was independently associated with higher risks of death (aOR 2.8; 95% CI 2.4-3.3), severe intraventricular hemorrhage (IVH) (aOR 2.1; 95% CI 1.8-2.5) and bronchopulmonary dysplasia (BPD) (aOR 2.2; 95% CI 2.0-2.5). Overall 63.1% courses of cardiovascular pharmacological support were >3 days. Prolonged cardiovascular pharmacological support (>3 days) was independently associated with lower rates of survival without morbidity in very-low-birth-weight infants, compared with infants with shorter durations. Dopamine was the most commonly used cardiovascular agent. The cardiovascular pharmacological support rates varied from 1.9 to 65.8% among the participating NICUs. Conclusions: The rate of cardiovascular pharmacological support within the first postnatal week was high with prolonged durations in Chinese NICUs. Marked variation in cardiovascular support existed among participating NICUs. Cardiovascular pharmacological support during the early postnatal period, especially prolonged, may be associated with adverse neonatal outcomes. Clinical Trial Registration: The original trial was registered as "Reduction of Infection in Neonatal Intensive Care Units using the Evidence-based Practice for Improving Quality" (ID: NCT02600195) on clinicaltrials.gov. https://clinicaltrials.gov/ct2/show/NCT02600195?term=NCT02600195&draw=2&rank=1.

What Inotrope and Why?

Primary function of cardiovascular system is to meet body's metabolic demands. The aim of inotrope therapy is to minimise adverse impact of cardiovascular compromise. Current use of inotropes is primarily guided by the pathophysiology of cardiovascular compromise and anticipated actions of inotropes. Lack of significant reduction in morbidity and mortality associated with cardiovascular compromise despite inotrope use, highlights major gaps in our understanding of circulatory targets, thresholds and choices of inotrope therapy. Thus far, prevention of cardiovascular compromise remains the most effective strategy to optimize outcomes. Studies of alternative design are needed for further advancement in cardiovascular therapy in neonates.

Corticosteroids for Neonatal Hypotension

Several limitations and controversies surround the definition of hypotension; however, it remains one of the most common problems faced by neonates. Approximately 15% to 30% of neonates with hypotension fail to respond to volume and/or vasopressor or inotropes. They are considered to have refractory hypotension. Although it is thought to have multiple causes, absolute and relative adrenal insufficiency is considered as the main reason for refractory hypotension. This article focuses on the role of adrenal insufficiency in causing refractory hypotension in preterm and term infants, the different options of corticosteroids available, and their risk/benefit profiles.

Neonatal adrenal insufficiency: Turkish Neonatal and Pediatric Endocrinology and Diabetes Societies consensus report

It is difficult to make a diagnosis of adrenal insufficiency in the newborn, because the clinical findings are not specific and the normal serum cortisol level is far lower compared to children and adults. However, dehydratation, hyperpigmentation, hypoglycemia, hyponatremia, hyperkalemia and metabolic acidosis should suggest the diagnosis of adrenal insufficiency. Hypotension which does not respond to vasopressors should especially be considered a warning. If the adrenocorticotropin hormone level measured simultaneously with a low serum cortisol level is 2-fold higher than the upper normal limit of the reference range, a diagnosis of primary adrenal insufficiency is definite. Even if the serum cortisol level is normal, a diagnosis of relative adrenal insufficiency can be made with clinical findings, if the patient is under heavy stress. The serum cortisol level should be measured using the method of ‘high pressure liquid chromatography’ or ‘LC mass spectrometry’. Adrenal steroid biosynthesis can be evaluated more specifically and sensitively with ‘steroid profiling’. Rennin and aldosterone levels may be measured in addition to serum electrolytes for the diagnosis of mineralocorticoid insufficiency. Adrenocorticotropic hormone stimulation test may be used to confirm the diagnosis and elucidate the etiology. In suspicious cases, treatment can be initiated without waiting for the adrenocorticotropic hormone stimulation test. In schock which does not respond to vasopressors, intravenous hydrocortisone at a dose of 50-100 mg/m² or a glucocorticoid drug at an equivalent dose should be initiated. In maintanence treatment, the physiological secretion rate of hydrocortisone is 6 mg/m²/day (15 mg/m²/day in the newborn). The replacement dose should be adjusted with clinical follow-up and by monitoring growth rate, weight gain and blood pressure. Fludrocortisone (0,1 mg tablet) is given for mineralocorticoid treatment (2x0,5-1 tablets). A higher dose may be needed in the neonatal period and in patients with aldosterone resistance. If hyponatremia persists, oral NACl may be added to treatment. In the long-term follow-up, patients should carry an identification card and the glucocorticoid dose should be increased 3-10-fold in cases of stress.

The Use of Cardiotonic Drugs in Neonates

There is a distinct lack of age-appropriate cardiotonic drugs, and adult derived formulations continue to be administered, without evidence-based knowledge on their dosing, safety, efficacy, and long-term effects. Dopamine remains the most commonly studied and prescribed cardiotonic drug in the neonatal intensive care unit (NICU), but evidence of its effect on endorgan perfusion still remains. Unlike adult and pediatric critical care, there are significant gaps in our knowledge on the use of various cardiotonic drugs in various forms of circulatory failure in the NICU.

The Association of Hydrocortisone Dosage on Mortality in Infants Born Extremely Premature

OBJECTIVE

To characterize common dosing strategies and to investigate the association between hydrocortisone dosage and in-hospital mortality in infants born extremely premature.

STUDY DESIGN

We performed a retrospective review of a cohort of infants born ≤30 weeks' gestational age from 2010 to 2016 from the Pediatrix Clinical Data Warehouse who received hydrocortisone in the first 14 postnatal days. Infants were divided by initial hydrocortisone dosage (high: >2 mg/kg/d vs low: ≤2 mg/kg/d). Baseline characteristics and medication coexposures were compared and mortality was evaluated in a multivariable analysis.

RESULTS

A total of 1427 infants were included, 733 with high dosage (51%) and 694 with low dosage (49%). The groups were similar with regard to baseline characteristics. Infants in the high-dosage group had significantly more exposure to any vasopressors (89% vs 84%, P < .001) and greater mortality (50% vs 23%, P < .001) vs the low-dosage group. High dosage of hydrocortisone was associated independently with death (aOR 3.27, 95% CI 2.47-4.34, P < .001) in a multivariable regression analysis including propensity scoring for dosage and other covariates. When the cohort was split into quartiles by dosage, mortality was lower in the lower-dosage quartiles compared with the higher quartiles (mortality range 13%-50%).

CONCLUSIONS

In this retrospective analysis of a large sample of infants born premature, increased initial hydrocortisone dosage was associated independently with increased mortality. Trials to assess the impact of hydrocortisone dosage in this population are needed.

Dobutamine treatment reduces inflammation in the preterm fetal sheep brain exposed to acute hypoxia

BACKGROUND

Impaired cerebral autoregulation in preterm infants makes circulatory management important to avoid cerebral hypoxic-ischemic injury. Dobutamine is frequently used as inotropic treatment in preterm neonates, but its effects on the brain exposed to cerebral hypoxia are unknown. We hypothesized that dobutamine would protect the immature brain from cerebral hypoxic injury.

METHODS

In preterm (0.6 gestation) fetal sheep, dobutamine (Dob, 10 μg/kg/min) or saline (Sal) was infused intravenously for 74 h. Two hours after the beginning of the infusion, umbilical cord occlusion (UCO) was performed to produce fetal asphyxia (Sal+UCO: n = 9, Dob+UCO: n = 7), or sham occlusion (Sal+sham: n = 7, Dob+sham: n = 6) was performed. Brains were collected 72 h later for neuropathology.

RESULTS

Dobutamine did not induce cerebral changes in the sham UCO group. UCO increased apoptosis and microglia density in white matter, hippocampus, and caudate nucleus, and astrocyte density in the caudate nucleus. Dobutamine commenced before UCO reduced microglia infiltration in the white matter, and microglial and astrocyte density in the caudate.

CONCLUSION

In preterm hypoxia-induced brain injury, dobutamine decreases neuroinflammation in the white matter and caudate, and reduces astrogliosis in the caudate. Early administration of dobutamine in preterm infants for cardiovascular stabilization appears safe and may be neuroprotective against unforeseeable cerebral hypoxic injury.

Dopamine plasma clearance is increased in piglets compared to neonates during continuous dopamine infusion

AIM

Piglets models have often been used to study the effects of dopamine infusion on hypotension in neonates. However, piglets need higher doses of dopamine than neonates to increase blood pressure. We investigated whether this difference was due to interspecific difference in dopamine pharmacokinetics.

METHODS

Arterial blood samples were drawn from six neonates admitted to the neonatal intensive care unit of Copenhagen University Hospital and 20 newborn piglets during continuous dopamine infusion. Furthermore, to estimate the piglet plasma dopamine half-life, blood samples were drawn at 2.5-minute intervals after the dopamine infusion was discontinued. The plasma dopamine content was analysed by high-performance liquid chromatography with electrochemical detection.

RESULTS

The dopamine displayed first-order kinetics in piglets and had a half-life of 2.5 minutes, while the median plasma clearance was 627.9 mL/kg/minute (interquartile range 452.6-1914.4). Both piglets and neonates showed large interindividual variations in plasma clearance, but the median tended to be lower in neonates (384.9, interquartile range 114.2-480.2 mL/kg/minute).

CONCLUSION

Our results suggest that pharmacokinetic differences may explain the interspecific difference in required doses of dopamine infusion to increase blood pressure. This is important when translating the results obtained in piglet models to treating neonatal hypotension with dopamine.

Treating Hypotension in Preterm Neonates With Vasoactive Medications

Preterm neonates often have hypotension which may be due to various etiologies. While it is controversial to define hypotension in preterm neonates, various vasoactive medications are commonly used to provide the cardiovascular support to improve the blood pressure, cardiac output, or to treat shock. However, the literature on the systemic and regional hemodynamic effects of these antihypotensive medications in neonates is deficient and incomplete, and cautious translation of findings from other clinical populations and animal studies is required. Based on a literature search on published reports, meta-analytic reviews, and selected abstracts, this review discusses the current available information on pharmacologic actions, clinical effects, and side effects of commonly used antihypotensive medications including dopamine, dobutamine, epinephrine, norepinephrine, vasopressin, and milrinone in preterm neonates.

Inotropes for Preterm Infants: 50 Years on Are We Any Wiser?

For almost half a century, inotropes have been administered to preterm infants with the ultimate goal of increasing their blood pressure. A number of trials, the majority of which focused on dopamine administration, have demonstrated increased blood pressure following inotrope administration in preterm infants and have led to continued use of inotropes in our neonatal units. We have also seen an increase in the number of potential agents available to the clinician. However, we now know that hypotension is a much broader concept than blood pressure alone, and our aim should instead be focused on improving end organ perfusion, specifically cerebral perfusion. Only a limited number of studies have incorporated the organ-relevant hemodynamic changes and long-term outcomes when assessing inotropic effects in neonates, the majority of which are observational studies or have a small sample size. In addition, important considerations, including the developing/maturing adrenergic receptors, polymorphisms of these receptors, and other differences in the pharmacokinetics and pharmacodynamics of preterm infants, are only recently being recognized. Certainly, there remains huge variation in practice. The lack of well-conducted randomized controlled trials addressing these relevant outcomes, along with the difficulty executing such RCTs, leaves us with more questions than answers. This review provides an overview of the various inotropic agents currently being used in the care of preterm infants, with a particular focus on their organ/cerebral hemodynamic effects both during and after transition.

Cardiovascular Supportive Therapies for Neonates With Asphyxia - A Literature Review of Pre-clinical and Clinical Studies

Asphyxiated neonates often have hypotension, shock, and poor tissue perfusion. Various "inotropic" medications are used to provide cardiovascular support to improve the blood pressure and to treat shock. However, there is incomplete literature on the examination of hemodynamic effects of these medications in asphyxiated neonates, especially in the realm of clinical studies (mostly in late preterm or term populations). Although the extrapolation of findings from animal studies and other clinical populations such as children and adults require caution, it seems appropriate that findings from carefully conducted pre-clinical studies are important in answering some of the fundamental knowledge gaps. Based on a literature search, this review discusses the current available information, from both clinical studies and animal models of neonatal asphyxia, on common medications used to provide hemodynamic support including dopamine, dobutamine, epinephrine, milrinone, norepinephrine, vasopressin, levosimendan, and hydrocortisone.

Use of Vasopressin in Neonatal Intensive Care Unit Patients With Hypotension

OBJECTIVE

To evaluate the safety and efficacy of vasopressin for the treatment of hypotension in patients admitted to neonatal intensive care units (NICUs).

METHODS

Vasopressin use in 69 infants admitted to our NICU between 2011 and 2014 was examined. Data evaluated included demographics; serum creatinine, sodium, and lactate concentrations; urine output; and systolic, diastolic, and mean blood pressures (BPs). Parameters prior to vasopressin use were compared to those at maximum dose.

RESULTS

Vasopressin use was associated with increased urine output (p < 0.05), and increased systolic (p < 0.0005), diastolic (p < 0.01), and mean (p < 0.001) BP. There were no differences in sodium or lactate concentrations before vs during infusion; vasopressin use was not associated with hyponatremia (sodium < 130 mEq/L) at the maximum dose.

CONCLUSIONS

Vasopressin for the treatment of neonatal hypotension appears safe and was efficacious in raising BP. These data suggest that vasopressin could be considered a viable option in the treatment regimen in hypotensive infants in the NICU.

Neurodevelopmental outcomes of neonates undergoing surgery under general anesthesia for malrotation of intestines

BACKGROUND

It is difficult to differentiate between the potential adverse effects of general anesthesia (GA) on the developing brain and the role of associated co-morbidities and syndromes that can adversely affect neurodevelopmental outcomes in neonates undergoing GA. Neonates with malrotation of the intestines without volvulus usually do not have co-morbidities or syndromes. In addition, majority of them recover very well after surgery and are discharged home within a few days. Neonates with malrotation are a clean cohort of babies to study the role of a single episode of GA on the developing brain.

AIMS

The study aimed to evaluate the neurodevelopmental outcomes of neonates undergoing GA for malrotation surgery.

STUDY DESIGN

Retrospective review of neonates born at gestational age of ≥32weeks undergoing laparotomy for malrotation.

OUTCOME MEASURES

Neurodevelopment in the study cohort at the age of one year.

RESULTS

33 eligible infants were identified from the departmental database. All 33 survived and were assessed using the Griffiths Mental Development Scales (GMDS) at one year. Mean general quotient (GQ) of the study population was 98 (SD 7.33) which was similar to the population norms (100.2, SD 12.8); p value 0.10. None of the infants developed cerebral palsy, tone abnormality, sensorineural deafness or blindness. There was no significant difference in the centiles at birth versus one year for weight and length (p values 0.454 and 0.178 respectively). Reassuringly, the head circumference centiles at one year showed a trend towards higher values (p value: 0.0735).

CONCLUSION

One year developmental outcomes of neonates undergoing surgery under GA for malrotation were similar to population norms.

Dopamine therapy does not affect cerebral autoregulation during hypotension in newborn piglets

Background

Hypotensive neonates who have been treated with dopamine have poorer neurodevelopmental outcome than those who have not been treated with dopamine. We speculate that dopamine stimulates adrenoceptors on cerebral arteries causing cerebral vasoconstriction. This vasoconstriction might lead to a rightward shift of the cerebral autoregulatory curve; consequently, infants treated with dopamine would have a higher risk of low cerebral blood flow at a blood pressure that is otherwise considered “safe”.

Methods

In anaesthetized piglets, perfusion of the brain, monitored with laser-doppler flowmetry, and cerebral venous saturation was measured at different levels of hypotension. Each piglet was studied in two phases: a phase with stepwise decreases in MAP and a phase with stepwise increases in MAP. We randomized the order of the two phases, whether dopamine was given in the first or second phase, and the infusion rate of dopamine (10, 25, or 40 μg/kg/min). In/deflation of a balloon catheter, placed in vena cava, induced different levels of hypotension. At each level of hypotension, fluctuations in MAP were induced by in/deflations of a balloon catheter in descending aorta.

Results

During measurements, PaCO₂ and arterial saturation were stable. MAP levels ranged between 14 and 82 mmHg. Cerebral autoregulation (CA) capacity was calculated as the ratio between %-change in cerebrovascular resistance and %-change in MAP induced by the in/deflation of the arterial balloon. A breakpoint in CA capacity was identified at a MAP of 38±18 mmHg without dopamine and at 44±18, 31±14, and 24±14 mmHg with dopamine infusion rates of 10, 25, and 40 μg/kg/min (p = 0.057). Neither the index of steady-state cerebral perfusion nor cerebral venous saturation were affected by dopamine infusion.

Conclusion

Dopamine infusion tended to improve CA capacity at low blood pressures while an index of steady-state cerebral blood flow and cerebral venous saturation were unaffected by dopamine infusion. Thus, dopamine does not appear to impair CA in newborn piglets.

Hydrocortisone for Treatment of Hypotension in the Newborn

Newborns, and especially premature newborns, are at significant risk for developing hypotension in the first week or two after birth. The etiology of hypotension in the newborn may vary, but the very low birth weight and extremely low birth weight preterm infants are less likely to respond to conventional cardiovascular support when they develop hypotension. This article reviews the least conventional treatment using hydrocortisone for hypotension that is refractory to conventional volume replacement and/or vasopressor medications with the underlying assumption that sick and premature newborns have a relative or measured adrenal insufficiency. The addition of hydrocortisone in the treatment of hypotension in the newborn is becoming more common but is not universally advocated. However, the supportive evidence is growing, and, as reviewed, use of hydrocortisone requires judicious and cautious regard.

Adrenocortical insufficiency and refractory hypotension in preterm infants

Preterm, very low birthweight (VLBW) infants are prone to life-threatening hypotension secondary to hypothalamic-pituitary-adrenal axis immaturity, resulting in adrenocortical insufficiency. Clinical presentations of inotrope-resistant refractory hypotension are usually evident, but interpretation of serum cortisol may pose much difficulty to front-line neonatologists. This review examines the salient pathophysiology of adrenocortical insufficiency in the immediate postnatal period, characterises its endocrinological abnormalities, and describes the typical and variant clinical presentations. Based on existing evidence, a practical scheme is proposed for logical interpretation of circulating cortisol levels and management of inotrope-resistant refractory hypotension in VLBW infants.

Inotropic Therapy in Newborns, A Population-Based National Registry Study

OBJECTIVE

To describe the use of inotropic drugs and the characteristics of neonates receiving such treatment in a national cohort of patients admitted to neonatal ICUs in Norway.

DESIGN

A national registry study of patients included in the Norwegian Neonatal Network database 2009-2014. Demographic and treatment data, including the use of inotropic drugs (dopamine, dobutamine, epinephrine, norepinephrine, milrinone, and levosimendan) and outcomes, were retrieved and analyzed.

SETTING

Neonatal ICUs in Norway.

PATIENTS

All patients admitted to Norwegian neonatal ICUs 2009-2014 with a postmenstrual age of less than 310 days at admission, corresponding to a postnatal age of less than 28 days for a child born at term (n = 36 397).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Inotropic drugs were administered to 974 of 361,803 live born infants (0.27%) in the study period, representing 2.7% of the neonatal ICU patient population. The relative proportion of neonatal ICU patients receiving inotropes decreased with increasing gestational age, yet 41% of the patients receiving inotropes were born at term. Of note, 89.8% of treated patients received dopamine. Use of inotropes was particularly prevalent in patients with necrotizing enterocolitis (72.4%) and pulmonary hypertension (42.1%) and in patients with gestational age less than 28 weeks (28.2%). Inotropic treatment initiated in the first week of life (84.2%) was associated with birth asphyxia and pulmonary hypertension, whereas treatment initiated after the first week of life was associated with extremely preterm birth, neonatal surgery, neonatal sepsis, cardiac disease, and necrotizing enterocolitis.

CONCLUSIONS

This comprehensive epidemiologic study indicates that less than 0.3% of newborns receive inotropic support in the neonatal period. Dopamine was the most commonly used drug. Relating inotrope use to clinical condition, gestational age, and postnatal age may be useful for clinicians and helpful in delineating relevant patient populations for future clinical trials.

Should dopamine be the first line inotrope in the treatment of neonatal hypotension? Review of the evidence

AIM: To determine if dopamine is effective in treating neonatal hypotension and safe to use comparing to other inotropes.

METHODS: This is a review of evidence on inotropic treatment of neonatal hypotension. Databases searched were MEDLINE and the Cochrane Library, a total of 134 studies were identified. Only studies with high quality evidence (level 1a and b and 2a) were included. After review, only eight studies were included in the final analysis. Pooled risk ratios derived for each outcome [Mantel-Haenzel (M-H) fixed effect] with CI, as reported in the Cochrane reviews were plotted in forest plot form.

RESULTS: Eight articles met inclusion criteria, which all included treatment in preterm infants. Dopamine increased mean arterial blood pressure (BP) (n = 163; r = 0.88, 95%CI: 0.76 to 0.94) and systolic BP (n = 142; r = 0.81, 95%CI: 0.42 to 0.94) comparing to placebo. Dopamine has been shown overall to be statistically more effective in increasing BP than dobutamine (n = 251, r = 0.26, 95%CI: 0.20-0.32). However there were no differences in short term outcomes (periventricular leucomalacia, periventricular haemorrhage) and mortality between both drugs. There is no statistical evidence of dopamine being more effective than adrenaline or corticosteroids. There was no difference in morbidity and mortality outcomes when dopamine was compared to hydrocortisone (RR 1.81, 95%CI: 0.18 to 18.39) or adrenaline.

CONCLUSION: In preterms, dopamine is the most studied drug, and we suggest it could be used as first line treatment in hypotension.

Secondary Increase of Lactate Levels in Asphyxiated Newborns during Hypothermia Treatment: Reflect of Suboptimal Hemodynamics (A Case Series and Review of the Literature)

Objective To evaluate whether a secondary increase of serum lactate levels in asphyxiated newborns during hypothermia treatment may reflect suboptimal dynamics. Methods-Retrospective case series and review of the literature. We present the clinical course of four asphyxiated newborns treated with hypothermia who presented with hypotension requiring inotropic support, and who displayed a secondary increase of serum lactate levels during hypothermia treatment. Serial serum lactate levels are correlated with blood pressure and inotropic support within the first 96 hours of life. Results Lactate levels initially decreased in the four patients. However, each of them started to present lower blood pressure, and lactate levels started to increase again. Inotropic support was started to raise blood pressure. The introduction of an epinephrine drip consistently worsened the increase of lactate levels in these newborns, whereas dopamine and dobutamine enabled the clearance of lactate in addition to raising the blood pressure. Rewarming was associated with hemodynamics perturbations (a decrease of blood pressure and/or an increase of lactate levels) in the three newborns who survived. Conclusions Lactate levels during the first 4 days of life should be followed as a potential marker for suboptimal hemodynamic status in term asphyxiated newborns treated with hypothermia, for whom the maintenance of homeostasis during hypothermia treatment is of utmost importance to alleviate brain injury.

Vasopressin versus dopamine for treatment of hypotension in extremely low birth weight infants: a randomized, blinded pilot study

OBJECTIVE

To evaluate vasopressin vs dopamine as initial therapy in extremely low birth weight (ELBW) infants with hypotension during the first 24 hours of life.

STUDY DESIGN

ELBW infants with hypertension ≤ 30 weeks' gestation and ≤ 24 hours old randomly received treatment with vasopressin or dopamine in a blinded fashion. Normotensive infants not receiving vasopressor support served as a comparison group.

RESULTS

Twenty ELBW infants with hypertension received vasopressin (n = 10) or dopamine (n = 10), and 50 were enrolled for comparison. Mean gestational age was 25.6 ± 1.4 weeks and birth weight 705 ± 154 g. Response to vasopressin paralleled that of dopamine in time to adequate mean blood pressure (Kaplan-Meier curve, P = .986); 90% of infants in each treatment group responded with adequate blood pressure. The vasopressin group received fewer doses of surfactant (P < .05), had lower PaCO2 values (P < .05), and were not tachycardic (P < .001) during vasopressin administration, compared with the dopamine group.

CONCLUSIONS

Vasopressin in ELBW infants as the initial agent for early hypotension appeared safe. This pilot study supports a larger randomized controlled trial of vasopressin vs dopamine therapy in ELBW infants with hypotension.