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

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.

Dopamine or norepinephrine for sepsis-related hypotension in preterm infants: a retrospective cohort study

The purpose of this study is to compare the clinical effectiveness of dopamine (DA) versus norepinephrine (NE) as first-line therapy for sepsis-related hypotension in preterm infants. This is a retrospective cohort study over 10 years at two tertiary neonatal units. Preterm infants born < 35 weeks post-menstrual age (PMA), who received DA or NE as primary therapy for hypotension during sepsis, defined as culture-positive or culture-negative infections or necrotizing enterocolitis (NEC), were included. Episode-related mortality (< 7 days from treatment), pre-discharge mortality, and major morbidities among survivors were compared between two groups. Analyses were adjusted using the inverse probability of treatment weighting estimated by propensity score (PS). A total of 156 infants were included, 113 received DA and 43 NE. The mean ± SD PMA at birth and at treatment for the DA and NE groups were 25.8 ± 2.3 vs. 25.2 ± 2.0 weeks and 27.7 ± 3.0 vs. 27.1 ± 2.6 weeks, respectively (p > 0.05). Pre-treatment, the NE group had higher mean airway pressure (14 ± 4 vs. 12 ± 4 cmH₂O), heart rate (185 ± 17 vs. 175 ± 17 beats per minute), and median (IQR) fraction of inspired oxygen [0.67 (0.42, 1.0) vs. 0.52 (0.32, 0.82)] (p < 0.05 for all). After PS adjustment, NE was associated with lower episode-related mortality [adjusted odds ratio (95% CI) 0.55 (0.33, 0.92)], pre-discharge mortality [0.60 (0.37, 0.97)], post-illness new diagnosis of significant neurologic injury [0.32 (0.13, 0.82)], and subsequent occurrence of NEC/sepsis among the survivors [0.34, (0.18, 0.65)].

CONCLUSION

NE may be more effective than DA for management of sepsis-related hypotension among preterm infants. These data provide a rationale for prospective evaluation of these commonly used agents.

WHAT IS KNOWN

•Dopamine is the commonest vasoactive agent used to support blood pressure among preterm infants. •For adult patients, norepinephrine is recommended as the preferred therapy over dopamine for septic shock.

WHAT IS NEW

•This is the first study examining the relative clinical effectiveness of dopamine and norepinephrine as first-line pharmacotherapy for sepsis-related hypotension among preterm infants. •Norepinephrine use may be associated with lower mortality and morbidity than dopamine in preterm infants with sepsis.

Neonatal fluid overload-ignorance is no longer bliss

Excessive accumulation of fluid may result in interstitial edema and multiorgan dysfunction. Over the past few decades, the detrimental impact of fluid overload has been further defined in adult and pediatric populations. Growing evidence highlights the importance of monitoring, preventing, managing, and treating fluid overload appropriately. Translating this knowledge to neonates is difficult as they have different disease pathophysiologies, and because neonatal physiology changes rapidly postnatally in many of the organ systems (i.e., skin, kidneys, and cardiovascular, pulmonary, and gastrointestinal). Thus, evaluations of the optimal targets for fluid balance need to consider the disease state as well as the gestational and postmenstrual age of the infant. Integration of what is known about neonatal fluid overload with individual alterations in physiology is imperative in clinical management. This comprehensive review will address what is known about the epidemiology and pathophysiology of neonatal fluid overload and highlight the known knowledge gaps. Finally, we provide clinical recommendations for monitoring, prevention, and treatment of fluid overload.

Systematic Review and Meta-Analysis of Cardiovascular Medications in Neonatal Hypotension

Background

Comparative studies among the various cardiovascular medications used for the treatment of neonatal hypotension are lacking.

Methods

This systematic review and pairwise meta-analysis of the anti-hypotensive treatments in preterm and term infants was conducted to evaluate efficacy and impact on outcome. Electronic databases were searched up to February 2021 for relevant articles. As an extension of the current approach for study selection, a machine learning technique was used. Only randomized controlled trials (RCTs) of inotropes, pressors, volume therapy, and corticosteroids were included. Response to treatment was the primary outcome while secondary outcomes included mortality and common morbidities.

Results

Nineteen RCTs involving 758 preterm and term neonates were found, and 8 treatments were evaluated. Most studies involved subjects with early hypotension associated with prematurity. Pairwise meta-analysis among treatments showed that dopamine was more effective than dobutamine regarding the response to treatment (restoration of normotension or normalization of blood pressure) (7 trials, 286 neonates, odds ratio, 3.06 [95% CI = 1.06–8.87]; I² = 49%, very low quality of the evidence per GRADE). Comparisons of other treatments were not significant. No differences were found among regimens regarding survival and other secondary outcomes.

Conclusion

In this systematic review and pairwise meta-analysis, only the comparison of dopamine versus dobutamine provided evidence for efficacy of treatment and favored dopamine. No safe conclusions could be reached in regard to other treatments. Data regarding the management of arterial hypotension in conditions other than transition after birth in preterm newborns are sparse both in preterm and term infants.

Association between amount of dopamine and infections in extremely preterm infants

This study aimed to assess the effect of dopamine on the development of infections after birth in extremely preterm infants. We retrospectively identified 258 extremely preterm infants (born at < 28 gestational weeks) between July 2009 and December 2018 in a tertiary neonatal intensive care unit (NICU). We extracted data on potential risk factors for infection, total amount of dopamine, and infection history during NICU stay for each infant. We compared the infection group with the non-infection group, and used the Cox proportional hazard regression analysis to identify risk factors for infection during NICU stay. After adjustment for all potential risk factors, factors that significantly affected development of infection were gestational age (hazard ratio [HR], 0.70; 95% confidence interval [CI] 0.55-0.89; p = 0.004) and total amount of dopamine (HR, 1.04; 95% CI 1.02-1.07; p = 0.002). The receiver operating characteristic curve of total amount of dopamine for infection suggested that total amount of dopamine greater than 7.271 mg/kg predicted infection development with 80.4% sensitivity and 41.7% specificity.Conclusion: A large amount of dopamine can increase infections in extremely preterm infants. We should avoid using a large amount of dopamine and remain aware of the potential development of infections in extremely preterm infants. What is Known: • Inotropes are often used for extremely preterm infants and dopamine is the most commonly used inotrope. • However, it is suggested that dopamine affects the immune system and related infections. What is New: • This is the first study of the association between the amount of dopamine and infection in extremely preterm infants. • We should avoid using a large amount of dopamine in extremely preterm infants.

Complications associated with the current sequential pharmacological management of early postnatal hypotension in extremely premature infants

Early postnatal hypotension in premature infants is treated with escalating doses of vasopressor-inotropes (VI), followed by hydrocortisone if VI therapy fails. The adverse effects of this standard clinical practice have not been well reported. In a retrospective case-control study, we compared the complications associated with VI and hydrocortisone (HCVI) treatments in extremely low-birth-weight infants (≤1000 g) with contemporaneous normotensive medication-naïve controls via standard univariate and multivariate analyses. Birth weight, gestational age, and receipt of antenatal steroids did not differ between VI (n = 74) and control (n = 124) groups, while the occurrence of gestational diabetes mellitus and risks for patent ductus arteriosus, intraventricular-periventricular hemorrhage, spontaneous intestinal perforation, ventriculomegaly, and bronchopulmonary dsyplasia were higher in VI. Infants in the HCVI group (n = 69) had lower birth weight, gestational age, and receipt of antenatal steroids and higher risks for intraventricular-periventricular hemorrhage, bronchopulmonary dysplasia, air leaks, and patent ductus arteriosus than controls. Whereas the occurrences of spontaneous intestinal perforation, ventriculomegaly, and maternal diabetes mellitus did not differ, that of maternal hypertension trended to be lower in HCVI recipients (P = 0.06). In conclusion, hypotensive extremely low-birth-weight infants treated with VI or with HCVI are susceptible to intraventricular-periventricular hemorrhage, bronchopulmonary dysplasia, and patent ductus arteriosus. Furthermore, those who receive inotropes are at risk for spontaneous intestinal perforation and ventriculomegaly. Maternal diabetes mellitus increases the occurrence of hypotension, which responds to VI. Maternal hypertension does not contribute to VI responsive and tends to decrease the occurrence of VI-refractory hypotension.

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.