The Role of Terlipressin in Pediatric Septic Shock: A Review of the Literature and Personal Experience

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.

American College of Critical Care Medicine Clinical Practice Parameters for Hemodynamic Support of Pediatric and Neonatal Septic Shock

OBJECTIVES

The American College of Critical Care Medicine provided 2002 and 2007 guidelines for hemodynamic support of newborn and pediatric septic shock. Provide the 2014 update of the 2007 American College of Critical Care Medicine "Clinical Guidelines for Hemodynamic Support of Neonates and Children with Septic Shock."

DESIGN

Society of Critical Care Medicine members were identified from general solicitation at Society of Critical Care Medicine Educational and Scientific Symposia (2006-2014). The PubMed/Medline/Embase literature (2006-14) was searched by the Society of Critical Care Medicine librarian using the keywords: sepsis, septicemia, septic shock, endotoxemia, persistent pulmonary hypertension, nitric oxide, extracorporeal membrane oxygenation, and American College of Critical Care Medicine guidelines in the newborn and pediatric age groups.

MEASUREMENTS AND MAIN RESULTS

The 2002 and 2007 guidelines were widely disseminated, translated into Spanish and Portuguese, and incorporated into Society of Critical Care Medicine and American Heart Association/Pediatric Advanced Life Support sanctioned recommendations. The review of new literature highlights two tertiary pediatric centers that implemented quality improvement initiatives to improve early septic shock recognition and first-hour compliance to these guidelines. Improved compliance reduced hospital mortality from 4% to 2%. Analysis of Global Sepsis Initiative data in resource rich developed and developing nations further showed improved hospital mortality with compliance to first-hour and stabilization guideline recommendations.

CONCLUSIONS

The major new recommendation in the 2014 update is consideration of institution-specific use of 1) a "recognition bundle" containing a trigger tool for rapid identification of patients with septic shock, 2) a "resuscitation and stabilization bundle" to help adherence to best practice principles, and 3) a "performance bundle" to identify and overcome perceived barriers to the pursuit of best practice principles.

Therapeutic applications of vasopressin in pediatric patients

CONTEXT

Reports of successful use of vasopressin in various shock states and cardiac arrest has lead to the emergence of vasopressin therapy as a potentially major advancement in the management of critically ill children.

OBJECTIVE

To provide an overview of physiology of vasopressin, rationale of its use and dose schedule in different disease states with special focus on recent advances in the therapeutic applications of vasopressin.

DATA SOURCE

MEDLINE search (1966-September 2011) using terms vasopressin, terlipressin, arginine-vasopressin, shock, septic shock, vasodilatory shock, cardiac arrest, and resuscitation for reports on vasopressin/terlipressin use in children and manual review of article bibliographies. Search was restricted to human studies. Randomized controlled trials, cohort studies, evaluation studies, case series, and case reports on vasopressin/terlipressin use in children (preterm neonates to 21 years of age) were included. Outcome measures were analysed using following clinical questions: indication, dose and duration of vasopressin/terlipressin use, main effects especially on systemic blood pressure, catecholamine requirement, urine output, serum lactate, adverse effects, and mortality.

RESULTS

51 reports on vasopressin (30 reports) and terlipressin (21 reports) use in pediatric population were identified. A total of 602 patients received vasopressin/terlipressin as vasopressors in various catecholamine-resistant states (septic - 176, post-cardiotomy - 136, other vasodilatory/mixed shock - 199, and cardiac arrest - 101). Commonly reported responses include rapid improvement in systemic blood pressure, decline in concurrent catecholamine requirement, and increase in urine output; despite these effects, the mortality rates remained high.

CONCLUSION

In view of the limited clinical experience, and paucity of randomized controlled trials evaluating these drugs in pediatric population, currently no definitive recommendations on vasopressin/terlipressin use can be laid down. Nevertheless, available clinical data supports the use of vasopressin in critically ill children as a rescue therapy in refractory shock and cardiac arrest.

Continuous Terlipressin Infusion as Rescue Treatment in a Case Series of Children with Refractory Septic Shock

Background:

Despite intensive therapy, refractory pediatric septic shock has a high rate of morbidity and mortality. Additional treatments are needed to improve outcomes in such cases.

Objective:

To report the clinical effects of continuous terlipressin infusion as rescue treatment for children with septic shock refractory to high catecholamine doses.

Methods:

Sixteen episodes of catecholamine-resistant septic shock were recorded in 15 children (aged from newborn to 15 years) who received compassionate rescue treatment with terlipressin at 6 pediatric intensive care units. Terlipressin treatment consisted of a loading dose (20 μg/kg) followed by continuous infusion at a rate of 4–20 μg/kg/h. Terlipressin was titrated at increases of 1 μg/kg/h to maintain mean arterial pressure (MAP) in normal range for age and to reduce catecholamine dosage. The main outcome was survival of the episode. Secondary outcomes included hemodynamic effects, ischemia, and terlipressin-related adverse events.

Results:

Terlipressin increased median MAP from 48 (range 42–63) to 68 (45–115) mm Hg 30 minutes after terlipressin administration (p < 0.01). MAP was subsequently sustained, which allowed for the reduction of norepinephrine infusion from 2 μg/kg/min (1–4) at baseline to 1.5 μg/kg/min (0.4–4) at 1 hour, 1.3 μg/kg/min (0–8) at 4 hours, 1 μg/kg/min (0–2) at 12 hours, 0.45 μg/kg/min (0–1.4) at 24 hours, and 0 μg/kg/min (0–0.6) at 48 hours (p < 0.05 vs baseline in all cases). In 8 (50%) of the 16 septic shock episodes the patients survived, 7 (44%) without sequelae. One patient survived with sequelae (minor amputation and mild cutaneous ischemia). Eight patients had signs of ischemia at admission; terlipressin induced reversible ischemia in another 4 patients. Meningococcal infection, prior ischemia, and MAP were risk factors for mortality.

Conclusions:

Continuous terlipressin infusion may improve hemodynamics and survival in some children with refractory septic shock. Terlipressin could contribute to tissue ischemia.

Vasopressin in pediatric shock and cardiac arrest

OBJECTIVE

To review the physiology and the published literature on the role of vasopressin in shock in children.

DATA SOURCE

We searched MEDLINE (1966-2007), EMBASE (1980-2007), and the Cochrane Library, using the terms vasopressin, terlipressin, and shock and synonyms or related terms for relevant studies in pediatrics. We searched the online ISRCTN-Current Controlled Trials registry for ongoing trials. We reviewed the reference lists of all identified studies and reviews as well as personal files to identify other published studies.

RESULTS

Beneficial effects have been reported in vasodilatory shock and asystolic cardiac arrest in adults. Solid evidence for vasopressin use in children is scant. Observational studies have reported an improvement in blood pressure and rapid weaning off catecholamines during administration of low-dose vasopressin. Dosing in children is extrapolated from adult studies.

CONCLUSIONS

Vasopressin offers promise in shock and cardiac arrest in children. However, in view of the limited experience with vasopressin, it should be used with caution. Results of a double-blind, randomized controlled trial in children with vasodilatory shock will be available soon.

Substance P: An Inflammatory Peptide

Substance P (SP) is involved in neurogenic inflammation and in the pathogenesis of several inflammatory diseases, demonstrating that there is a narrow interrelationship between the nervous system and immunity. Macrophage functions are altered in stress, therefore, since SP is a macrophage activator, its biological effect has been intimately linked to stress. In fact, SP enhances LPS-induced macrophage TNFα production from stressed animals and stimulates the production of IL-8 CXC chemokine response in a mast cell line in vitro. The stress-induced cytokines from macrophage also alter and contribute to inflammation. Understanding the pathophysiology of inflammation and the role of the chemical mediator SP may improve inflammation management.

The Effect of Porcine Orexin a on C-Peptide Plasma Concentrations in Pigs

The hypothalamus and the neuropeptides that are produced and act within its neuronal circuits constitute an area of extensive laboratory research. In 1998, the neuropeptide, Orexin A, was discovered and isolated from the hypothalamus of the rat. An i.c.v. injection of Orexin A into the lateral ventricle of the rat's brain causes an increase in the consumption of food, and, apart from appetite, it also seems to be regulating many other normal functions of the organism, whose regulatory and metabolic mechanisms remain unknown to date. The neuropeptide is produced by a small cluster located in and round the lateral hypothalamic area. It has been known for decades that this area is involved in the regulation of feeding and energy homeostasis in mammals. The intravenous, subcutaneous, or i.c.v. injection of Orexin A causes changes in insulin and glucagon concentrations. The same effect is also seen under in vitro experimental conditions. In this study, we investigated the potential effects of i.c.v. administration of porcine Orexin A on c-peptide concentrations in the peripheral blood of pigs, and tested whether these changes are associated with the potential effect of the neuropeptide on the function of the pancreas.

Hypertonic Saline Solution in Children with Adenoidal Hyperytrophy: Preliminary Evidence

Adenoidal hypertrophy (AH) is a frequent problem in children. A preliminary study evidenced that intranasal hypertonic solutions may exert an anti-inflammatory activity. The aim of the study is to evaluate the effect of intranasal hypertonic or isotonic solutions in children affected with AH. For this purpose, 78 children with AH were evaluated in a randomised and controlled study. Inclusion criteria for the study required that each patient had to have a III or IV degree of AH on the initial endoscopic examination. Children were treated with intranasal hypertonic or isotonic saline solution for 8 weeks. After treatment, endoscopy was performed to evaluate AH degree. Hypertonic treatment was associated with significant (p<0.05) reduction of AH degree. There was a consistent reduction of children with III degree of AH. No adverse events were reported. This preliminary study demonstrates that an 8-week treatment with intranasal hypertonic solution is associated with significant reduction of AH. Therefore, this study evidences that hypertonic solution may exert an anti-inflammatory activity and is safe.