Therapeutic applications of vasopressin in pediatric patients

Development and validation of a novel reverse-phase high-performance liquid chromatography (RP-HPLC) method for the quantification of related substances of vasopressin injection: A characterization and comparative analysis of vasopressin formulation samples against vasostrict (RLD) in various diluents

In the present study, we developed and validated a sensitive, accurate, robust and simple RP-HPLC method for quantification of related substances of vasopressin (VPS) injection. The development phase prioritized the optimization of wavelength, mobile phase composition and column selection to enhance separation and sensitivity for the analytical evaluation of VPS injection. By considering peak symmetry, resolution and retention time, chromatographic conditions of VPS injection were established. The YMC PACK ODS AM (100×4.6) mm, 3μm was employed in the study. Mobile phase A was prepared with 0.113M NaH2PO4.H2O (pH 3.0) while mobile phase B was a 50:50 (v/v) ratio of acetonitrile and water, pumped through a flow rate of 1.0mL/min. VPS injection was exposed to thermal, photolytic, acid, base and peroxide degradation conditions and these were analysed by the current method. The method was validated following the guidelines set by the International Council for Harmonization guideline (ICH). The linearity studies demonstrating that a correlation coefficient value is more than 0.999 for VPS and its related substances. The detection and quantification limits for all related substances were found to be 0.01% and 0.05%, respectively. All the impurities exhibited consistent recoveries ranging from 85 to 105%. The unknown impurities were eluting at RRT 1.23 and RRT 1.25 in the RS methodology (HPLC-UV) of VPS injection are identified and assessed the impurity levels. Furthermore, aggregate profiles and secondary structure analysis studies were carried out using FTIR and LC-HRMS, comparing the VPS formulation samples with the reference listed drug (RLD) (Vasostrict) samples across various diluents.

Vasopressin associated hyponatremia in critically ill children: A cross-sectional study

Background

The association of hyponatremia with vasopressin therapy in children is controversial. We aimed to evaluate the incidence and severity of hyponatremia associated with the administration of vasopressin in critically ill pediatric patients.

Methods

This retrospective cross-sectional study included children younger than 14 years who were admitted to the pediatric or pediatric cardiac intensive care units and received vasopressin for at least 24 h.

Results

In total, 176 critically ill pediatric patients were enrolled, with a median age of 22 days (7.3–146). The mean sodium level was notably decreased from 143.5 mEq/L ± 7.15 at the baseline to 134.3 mEq/L ± 7.7 at the 72-hour measurement after the initiation of vasopressin and varied significantly at all intervals from the baseline measurement (P < 0.001). Twenty-four hours after the discontinuation of vasopressin, more than half of the patients had hyponatremia. The highest proportion had mild hyponatremia (32.8%), followed by moderate hyponatremia (13.1%), and profound hyponatremia (7.5%). The incidence of hyponatremia was independent of gender (P = 0.94) or age group (P = 0.087). However, more than two-thirds of the moderate-profound cases and more than one-third of mild cases were observed in the neonate group (P = 0.043). The vasopressin dose did not affect the incidence (P = 0.25) or the severity of the hyponatremia (P = 0.56). Notably, all laboratory and hemodynamic parameters varied significantly at the end of therapy, compared to the baseline.

Conclusions

Continuous monitoring for hyponatremia when children are placed on vasopressin is essential to protect against more severe complications.

Successful treatment of severe arterial hypotension and anuria in a preterm infant with renal tubular dysgenesis- a case report

Background

Oligohydramnios sequence can be caused by renal tubular dysgenesis (RTD), a rare condition resulting in pulmonary and renal morbidity. Besides typical features of Potter-sequence, the infants present with severe arterial hypotension and anuria as main symptoms. Establishing an adequate arterial blood pressure and sufficient renal perfusion is crucial for the survival of these infants.

Case presentation

We describe a male preterm infant of 34 + 0 weeks of gestation. Prenatally oligohydramnios of unknown cause was detected. After uneventful delivery and good adaptation the infant developed respiratory distress due to a spontaneous right-sided pneumothorax and required thoracocentesis and placement of a chest tube; he showed no major respiratory concerns thereafter and needed only minimal ventilatory support. Echocardiography revealed no abnormalities, especially no pulmonary hypertension. However, he suffered from severe arterial hypotension and anuria refractory to catecholamine therapy (dobutamine, epinephrine and noradrenaline). After 36 h of life, vasopressin therapy was initiated resulting in an almost immediate stabilization of arterial blood pressure and subsequent onset of diuresis. Therapy with vasopressin was necessary for three weeks to maintain adequate arterial blood pressure levels and diuresis. Sepsis and adrenal insufficiency were ruled out as inflammation markers, microbiological tests and cortisol level were normal. At two weeks of age, our patient developed electrolyte disturbances which were successfully treated with fludrocortisone. He did not need renal replacement therapy. Genetic analyses revealed a novel compound hyterozygous mutation of RTD. Now 17 months of age, the patient is in clinically stable condition with treatment of fludrocortisone and sodium bicarbonate. He suffers from stage 2 chronic kidney disease; blood pressure, motor and cognitive development are normal.

Conclusions

RTD is a rare cause of oligohydramnios sequence. Next to pulmonary hypoplasia, severe arterial hypotension is responsible for poor survival. We present the only second surviving infant with RTD, who did not require renal replacement therapy during the neonatal period. It can be speculated whether the use of vasopressin prevents renal replacement therapy as vasopressin increases urinary output by improving renal blood flow.

Safety and Efficacy of Terlipressin in Pediatric Distributive Shock: A Retrospective Analysis in 20 Children

INTRODUCTION

Data are still lacking about the use of terlipressin or vasopressin in the treatment of pediatric patients who are in a state of therapy-refractory shock.

OBJECTIVE

The aim of this study was to evaluate the effect of terlipressin on hemodynamics in children with distributive shock and to describe any severe side effects.

METHODS

Consecutive patients (n = 20) with catecholamine-resistant distributive shock who were treated with terlipressin were retrospectively enrolled in this study. We analyzed response in terms of mean arterial blood pressure, heart rate, vasoactive inotropic score (VIS), urinary output, and serum lactate.

RESULTS

The hemodynamics of 12 children significantly improved within 6 h of commencing terlipressin (mean blood pressure increase of ≥20 % without VIS increase, or mean blood pressure increase of ≥10 % with VIS decrease of ≥10 %). The hemodynamics of eight patients did not improve, regardless of treatment dosage or duration. More children died in the responders group (n = 7 [58.3 %]) than in the non-responders group (n = 2 [25.0 %]), but this was not statistically significant. Two patients (one in each group) who received high dosages of terlipressin developed rhabdomyolysis. One case of Takotsubo cardiomyopathy was observed, which could be related to terlipressin.

CONCLUSIONS

Although treatment with terlipressin resulted in rapid positive hemodynamic responses in some children, it did not seem to have a positive effect in other pediatric patients. Therefore, the possible benefits of terlipressin should be always weighed against potential severe adverse effects.

Selepressin and Arginine Vasopressin Do Not Display Cardiovascular Risk in Atherosclerotic Rabbit

BACKGROUND

Septic shock remains associated with significant mortality rates. Arginine vasopressin (AVP) and analogs with V1A receptor agonist activity are increasingly used to treat fluid-resistant vasodilatory hypotension, including catecholamine-refractory septic shock. Clinical studies have been restricted to healthy volunteers and catecholamine-refractory septic shock patients excluding subjects with cardiac co-morbidities because of presumed safety issues. The novel selective V1A receptor agonist selepressin, with short half-life, has been designed to avoid V2 receptor-related complications and long-term V1A receptor activation. Cardiovascular safety of selepressin, AVP, and the septic shock standard of care norepinephrine was investigated in a rabbit model of early-stage atherosclerosis.

METHODS

Atherosclerosis was established in New Zealand White rabbits using a 1% cholesterol-containing diet. Selepressin, AVP, or norepinephrine was administered as cumulative intravenous infusion rates to atherosclerotic and non-atherosclerotic animals.

RESULTS

Selepressin and AVP induced a slight dose-dependent increase in arterial pressure (AP) associated with a moderate decrease in heart rate, no change in stroke volume, and a moderate decrease in aortic blood flow (ABF). In contrast, norepinephrine induced a marked dose-dependent increase in AP associated with a lesser decrease in the heart rate, an increase in stroke volume, and a moderate increase in ABF. For all three vasopressors, there was no difference in responses between atherosclerotic and non-atherosclerotic animals.

CONCLUSION

Further studies should be considered using more advanced atherosclerosis models, including with septic shock, before considering septic shock clinical trials of patients with comorbidities. Here, selepressin and AVP treatments did not display relevant cardiovascular risk in early-stage rabbit atherosclerosis.

[Septic shock in intensive care units. Current focus on treatment]

Essential therapeutic principles in children with septic shock persist over time, although some new concepts have been recently incorporated, and fully awareness of pediatricians and intensivists is essential. Fluid resuscitation is a fundamental intervention, but the kind of ideal fluid has not been established yet, as each of these interventions has specific limitations and there is no evidence supportive of the superiority of one type of fluid. Should septic shock persists despite adequate fluid resuscitation, the use of inotropic medication and/or vasopressors is indicated. New vasoactive drugs can be used in refractory septic shock caused by vasopressors, and the use of hydrocortisone should be considered in children with suspected adrenal insufficiency, as it reduces the need for vasopressors. The indications for red blood cells transfusion or the optimal level of glycemia are still controversial, with no consensus on the threshold value for the use of these blood products or the initiation of insulin administration, respectively. Likewise, the use of high-volume hemofiltration is a controversial issue and further study is needed on the routine recommendation in the course of septic shock. Nutritional support is crucial, as malnutrition is a serious complication that should be properly prevented and treated. The aim of this paper is to provide update on the most recent advances as concerns the treatment of septic shock in the pediatric population.

Vasopressin improves hemodynamic status in infants with congenital diaphragmatic hernia

OBJECTIVE

To assess the ability of vasopressin to stabilize hemodynamics in infants with systemic hypotension secondary to congenital diaphragmatic hernia (CDH).

STUDY DESIGN

A retrospective chart review was performed to identify 13 patients with CDH treated with vasopressin for refractory hypotension to assess the effect of vasopressin on pulmonary and systemic hemodynamics and gas exchange in this setting. Data collected included demographics, respiratory support, inotropic agents, pulmonary and systemic hemodynamics, urine output, and serum and urine sodium levels during vasopressin therapy.

RESULTS

Vasopressin therapy increased mean arterial pressure and decreased pulmonary/systemic pressure ratio, heart rate, and fraction of inspired oxygen. In 6 of 13 patients, extracorporeal membrane oxygenation therapy was no longer indicated after treatment with vasopressin. Improvement in left ventricular function and oxygenation index after vasopressin initiation was associated with a decreased need for extracorporeal membrane oxygenation therapy. Prolonged vasopressin treatment was associated with hyponatremia, increased urine output, and increased urine sodium.

CONCLUSIONS

Vasopressin stabilized systemic hemodynamics without adverse effects on pulmonary hemodynamics in a subset of infants with CDH. Our results suggest a potential role for vasopressin therapy in patients with CDH with catecholamine-resistant refractory hypotension.

Vasopressin for the treatment of neonatal hypotension

Vasopressin (pitressin), also known as arginine vasopressin (AVP), is an antidiuretic hormone formed in the hypothalamus and secreted from the posterior pituitary gland. Various forms of exogenous vasopressin exist and have been used in neonates to treat conditions such as diabetes insipidus. Vasopressin has also been studied on a limited basis for use in the treatment of catecholamine-resistant hypotension in vasodilatory shock. Hypotension is a significant problem resulting in increased morbidity in preterm, septic, and postsurgical neonates. This article will discuss the role of vasopressin and its use as a therapeutic agent in the treatment of hypotension in the neonate.