Failure to tolerate continuous subcutaneous treprostinil in pediatric pulmonary hypertension patients.

Continuous subcutaneous (SubQ) treprostinil is an effective therapy for pediatric patients diagnosed with pulmonary hypertension (PH). To date, the clinical characteristics and factors associated with failure to tolerate this therapy have not been described. The purpose was to describe patient-reported factors contributing to SubQ treprostinil intolerance in pediatric patients with PH. A retrospective descriptive study was performed at 11 participating sites in the United States and Canada for patients younger than 21 years of age diagnosed with PH who failed treatment to tolerate SubQ treprostinil between January 1, 2009, and December 31, 2019. All data were summarized using descriptive statistics. Forty-one patients met the inclusion criteria. The average age at SQ treprostinil initiation, and length of treatment, was 8.6 years and 22.6 months, respectively. The average maximum dose, concentration, and rate were 95.8 ng/kg/min, 6.06 mg/mL, and 0.040 mL/h, respectively. The reasons for failure to tolerate SubQ treprostinil included intractable site pain (73.2%), frequent site changes (56.1%), severe site reactions (53.7%), infections (26.8%), and noncompliance/depression/anxiety (17.1%). Thirty-nine (95.1%) patients transitioned to a prostacyclin therapy with 23 patients transitioning to intravenous prostacyclin, 5 to inhaled prostacyclin, 5 to oral prostacyclin, and 7 to a prostacyclin receptor agonist. A subset of pediatric PH patients failed to tolerate SubQ treprostinil infusions despite advances in SubQ site maintenance and pain management strategies. Intractable site pain, frequent SubQ site changes, and severe localized skin reactions were the most common reasons for failure.

Factors determining change in treatment for ambulatory children with pulmonary arterial hypertension: Implications for monitoring.

While care models adapt to the COVID-19 pandemic with virtual and hybrid visits, clinical factors associated with treatment changes among ambulatory pediatric pulmonary arterial hypertension (PAH) patients are not well characterized. To understand which data critically altered treatment recommendations, we conducted a retrospective review among ambulatory children with Group 1 PAH to determine optimal visit and diagnostic strategies. Changes in management included: unplanned new treatments, dose modifications of vasodilators or diuretics, unscheduled hospitalizations, or changes to activity recommendations, catheterization schedule, or other testing. Factors prompting management changes were classified as symptoms, exam findings, or diagnostic tests. Across 398 ambulatory visits by 48 patients, 38 patients (79%) at 88 visits (22%) required change in management, most commonly in targeted PH medication. Changes were driven by symptoms alone (15%), diagnostic testing alone (47%), exam only (2%), symptoms and exam (2%), combination of testing and symptoms or testing and exam (25%), and other reasons (9%). Patients with World Health Organization functional Class IV (odds ratio [OR] 9.04 vs. Class I, p = 0.014) or Class III (OR 2.08 vs. Class I, p = 0.050) were more likely to undergo change in management. However, among Class I patients, 18% of visits generated changes in management because of test findings. While multiple factors affect management in ambulatory pediatric PH, neither symptoms nor exam was sufficient for identifying patients warranting clinical change in management. Testing accounted for most changes. Thus, in-person or hybrid surveillance including history, exam, and diagnostic testing remains essential for optimal management of pediatric PAH.

Pediatric subcutaneous treprostinil site maintenance and pain control strategies from the Pediatric Pulmonary Hypertension Network.

Pulmonary arterial hypertension is a chronic, progressive, and life-threatening disease in children with diverse causes of pulmonary arterial hypertension. The most severe cases of pulmonary arterial hypertension require aggressive treatments with systemic administration of continuous prostacyclin therapy, including treprostinil and epoprostenol. The successful use of continuous subcutaneous treprostinil therapy eliminates the need for an indwelling central venous catheter and its associated risks. However, pain at the subcutaneous infusion site, an expected side effect of this therapy, is often a deterrent to its widespread use. Effective subcutaneous treprostinil site maintenance and pain management is essential to achieve success with this therapy, but strategies surrounding site maintenance and pain control vary significantly between pediatric pulmonary hypertension treatment centers. In an attempt to standardize practice, a survey on the use of subcutaneous treprostinil and site maintenance and pain management strategies, as well as its perceived effectiveness, was disseminated to 13 pediatric pulmonary hypertension centers of the Pediatric Pulmonary Hypertension Network. Responses to the survey were collected and analyzed and were developed into a set of formalized strategies to facilitate knowledge sharing and standardization of practice.

Prostanoids in pediatric pulmonary hypertension: clinical response, time-to-effect, and dose-response.

For pediatric pulmonary arterial hypertension (PAH) patients treated with parenteral prostanoids, response predictors, and the dose-effect relationship are ill defined. We determined the following: (1) which pulmonary vascular hemodynamic variable, after initiating prostanoids, best correlates with a significant clinical response; (2) the time interval after treatment when if no pulmonary hemodynamic improvement has occurred, none is ever likely to; and (3) the relationship between the prostanoid dose and its hemodynamic effects. This is a retrospective cohort study of 31 pediatric patients with Group 1 PAH treated with parenteral prostanoids. We found the following: (1) A fall in mean pulmonary arterial pressure (mPAP) of ≥25% predicted freedom from adverse clinical events with 80.7% accuracy and was also associated with improved functional class. (2) Thirty-three percent of patients who avoided an adverse clinical event demonstrated a ≥25% reduction in mPAP after 1 year of treatment, and 65% by 2 years. (3) Lower mPAP was seldom seen with doses of epoprostenol >60 ng/kg/min (100 ng/kg/min for treprostinil). Cardiac index was positively correlated with the dose of epoprostenol but not treprostinil; cardiac index >4 l/min/m2 was seen at modest as well as high doses. We conclude that a ≥25% fall in mPAP on prostanoids indicates a positive clinical response which, if validated in other studies, may be useful for patient management or clinical trials. Some patients take more than 2 years for this change. Exceptionally high doses were generally not more effective than lower, although we could not determine whether lower doses would have been as effective.

Improving Safety of Intravenous Prostacyclin Administration to Pediatric Patients With Pulmonary Hypertension.

BACKGROUND: Pulmonary hypertension is a rare, life-threatening disease with limited therapeutic options and no definitive cure. Continuous intravenous prostacyclin therapy is indicated for treatment of severe disease. These medications have a narrow therapeutic index and a brief half-life; therefore, administration errors can be lethal. OBJECTIVE: To reduce medication errors through an inpatient program to improve, standardize, and disseminate continuous intravenous prostacyclin therapy practice guidelines. METHODS: Data were collected from the electronic safety reporting system of a single hospital to determine the number and types of continuous intravenous prostacyclin therapy errors that were reported over an 8-year period. A clinical database and hospital pharmacy records were used to determine the number of days on which hospitalized pediatric patients received the therapy. INTERVENTIONS: A nursing-directed quality improvement initiative to enhance the safety of continuous intravenous prostacyclin therapy for pediatric patients was begun in January 2009. Efforts to improve safety fell into 4 domains: policy, process, education, and hospital-wide safety initiatives. RESULTS: The number of therapy errors per 1000 patient days fell from 19.28 in 2009 to 5.95 in 2016. Chi-square analysis was used to compare the result for 2009 with that for each subsequent year, with P values of .66, .35, .16, .09, .03, .12, and .25 found for 2010 through 2016, respectively. CONCLUSIONS: The trend in reduction of continuous intravenous prostacyclin therapy errors suggests that proactive processes to standardize its administration, emphasizing both policy and education, reduce medication errors and increase patient safety.

Pulmonary Artery Banding in Post-tricuspid Congenital Cardiac Shunting Defects with High Pulmonary Vascular Resistance.

Reports of "treat and repair" of cardiac shunting lesions with inoperably high pulmonary vascular resistance (PVR) mostly concern pre-tricuspid defects; post-tricuspid lesions are different. We report our experience with pulmonary artery (PA) banding ± targeted pulmonary hypertension medications in five patients with a large VSD and inoperably high PVR, and review previous reports of PA banding with post-tricuspid defects. Three of our 5 patients had mean PAP > 50 mmHg after banding and no or only a transient fall in PVR. Two patients had mean PAP < 50 mmHg and lower PVR after banding; they had closure of their VSDs but have since had a progressive increase in PVR (follow-up after closure, 3.5 and 7.7 years). Previous reports have also documented difficulty in achieving sufficient band gradient. Of previously reported patients, only one became operable only after banding and targeted therapy, and was repaired; follow-up after repair was short-term (16 months). Our and previous experience demonstrate the difficulty in placing a PA band sufficiently tight to substantially reduce PA pressure. Reported attempts to "treat and repair" post-tricuspid defects are few and have met with limited success, and we found that PVR may increase significantly over time after repair. But more information is needed. Accurate interpretation of experience with "treat and repair" requires: careful characterization of the pulmonary circulation prior to "treating"; considering spontaneously reversible factors at pre-treatment catheterization before ascribing reduction in PVR to medical therapy; and long-term observation of PVR in patients who have had defect closure.

The impact of right ventricular pressure and function on survival in patients with pulmonary vein stenosis.

Pulmonary vein stenosis (PVS) is associated with pulmonary hypertension (PH), but there is little information regarding the impact of PH on right ventricular (RV) systolic function and survival. We conducted a retrospective cohort study of our patients to explore this and other aspects of pulmonary hemodynamics with PVS. RV function was assessed using qualitative two-dimensional echocardiography. The ratio of systolic pulmonary artery (PA) and aortic pressures (PA:Ao) at cardiac catheterization reflected pulmonary hemodynamics. Reactivity testing employed inhaled nitric oxide + 100% fiO2, or 100% fiO2 only; "reactivity" was a ≥ 20% decrease in PA:Ao. There were 105 PVS patients, although not all had data at every time point. (1) The mean PA:Ao at first cardiac catheterization (n = 77) was 0.79 ± 0.36; at last catheterization (n = 54), PA:Ao = 0.69 ± 0.30; 90% had systolic PAP > one-half systemic. Survival was shorter with PA:Ao > 0.5. (2) Differences in survival relative to RV dysfunction on the first echocardiogram were not significant, although they were using the last echocardiogram. (3) The magnitude of RV dysfunction was positively correlated with PA:Ao. (4) Balloon dilation of PV acutely decreased PA:Ao (-0.13 ± 0.37, P = 0.03 [n = 40 patients]). 5. Of 20 patients tested, 13 were acutely reactive to vasodilators. PH is a major feature of PVS. Reduced RV function and PA:Ao appear to be predictors of survival. Given the importance of PH in this disease, clinical studies of PVS treatments should include measures of PAP and RV function as important variables of interest.

Pediatric Cardiac Intensive Care Society 2014 Consensus Statement: Pharmacotherapies in Cardiac Critical Care Pulmonary Hypertension.

OBJECTIVE: To review the pharmacologic treatment options for pulmonary arterial hypertension in the cardiac intensive care setting and summarize the most-recent literature supporting these therapies. DATA SOURCES AND STUDY SELECTION: Literature search for prospective studies, retrospective analyses, and case reports evaluating the safety and efficacy of pulmonary arterial hypertension therapies. DATA EXTRACTION: Mechanisms of action and pharmacokinetics, treatment recommendations, safety considerations, and outcomes for specific medical therapies. DATA SYNTHESIS: Specific targeted therapies developed for the treatment of adult patients with pulmonary arterial hypertension have been applied for the benefit of children with pulmonary arterial hypertension. With the exception of inhaled nitric oxide, there are no pulmonary arterial hypertension medications approved for children in the United States by the Food and Drug Administration. Unfortunately, data on treatment strategies in children with pulmonary arterial hypertension are limited by the small number of randomized controlled clinical trials evaluating the safety and efficacy of specific treatments. The treatment options for pulmonary arterial hypertension in children focus on endothelial-based pathways. Calcium channel blockers are recommended for use in a very small, select group of children who are responsive to vasoreactivity testing at cardiac catheterization. Phosphodiesterase type 5 inhibitor therapy is the most-commonly recommended oral treatment option in children with pulmonary arterial hypertension. Prostacyclins provide adjunctive therapy for the treatment of pulmonary arterial hypertension as infusions (IV and subcutaneous) and inhalation agents. Inhaled nitric oxide is the first-line vasodilator therapy in persistent pulmonary hypertension of the newborn and is commonly used in the treatment of pulmonary arterial hypertension in the ICU. Endothelin receptor antagonists have been shown to improve exercise tolerance and survival in adult patients with pulmonary arterial hypertension. Soluble guanylate cyclase stimulators are the first drug class to be Food and Drug Administration approved for the treatment of chronic thromboembolic pulmonary hypertension. CONCLUSIONS: Literature and data supporting the safe and effective use of pulmonary arterial hypertension therapies in children in the cardiac intensive care are limited. Extrapolation of adult data has afforded safe medical treatment of pulmonary hypertension in children. Large multicenter trials are needed in the search for safe and effective therapy of pulmonary hypertension in children.

Central venous line complications with chronic ambulatory infusion of prostacyclin analogues in pediatric patients with pulmonary arterial hypertension.

Chronic infusion of prostacyclin (PGI2) via a Broviac central venous line (CVL) is attended by risk of CVL-related complications, but we know of only one report regarding CVL-associated bloodstream infection (BSI) with PGI2 in children and none regarding other complications. We conducted a retrospective cohort study involving pediatric patients with pulmonary hypertension treated with chronic intravenous infusion of PGI2 at Boston Children's Hospital and determined the rate (per 1,000 line-days) of various CVL-related complications. We also determined how often complications necessitated line replacement and hospitalization, time to replacement of CVLs, and interpatient variability in the incidence of complications. From 1999 until 2014, 26 patients meeting follow-up criteria had PGI2 infusion, representing 43,855 line-days; mean follow-up was 56 months (range, 1.4-161 months). The CVL complication rates (per 1,000 line-days) were as follows: CVL-BSI, 0.25; superficial line infection, 0.48; impaired integrity, 0.59; occlusion, 0.09; and malposition, 0.32. The total complication rate was 1.73 cases per 1,000 line-days. All CVL-BSI and malposition cases were treated with CVL removal and replacement. Of CVLs with impaired integrity, 23 could be repaired and 3 required replacement. Six of 21 superficial CVL infections required replacement of the CVL. Three of 4 occluded CVLs were replaced. CVL complications occasioned 65 hospitalizations. There was marked interpatient variability in the rate of complications, much but not all of which appeared to be related to duration of CVL placement. We conclude that non-BSI complications are very significant and that efforts to teach and emphasize other aspects of line care are therefore very important.

Quality of life and parental adjustment in pediatric pulmonary hypertension.

BACKGROUND: This study examines the impact of pulmonary hypertension (PH) on the quality of life (QoL) of affected youth, as well as the relationships among PH disease severity, parental adjustment variables, and family relational functioning. METHODS: Subjects were 47 eligible parents of children with PH aged 2 to 18 years who were evaluated at Boston Children's Hospital. Measures of patient QoL and of parental stress, coping, and adjustment were administered to the caregivers. Clinicians rated illness severity and family relational functioning. RESULTS: Youth with PH scored significantly lower than healthy norms on a measure of parent-reported QoL (total, psychosocial, and physical QoL, each P < .0001). The parents reported encountering stressful events more frequently than published norms of parents of children with cancer (P < .0001). Thirty-four percent of parents of children with PH met criteria for presumed psychiatric diagnosis, and they reported using psychologic coping strategies significantly more often than a normative sample. A summary parental stress measure correlated inversely with child QoL, an effect that held true even after controlling for disease severity (P = .03). CONCLUSIONS: PH takes a major toll on children and their families. Decreased QoL among youth with PH was significantly associated with high levels of parental stress, over and above the effect of illness severity. These findings suggest that interventions to better support the caretakers of affected children and adolescents should accompany medical treatment advances so as to improve QoL for patients facing pediatric PH.

"Nocturnal seizures" in idiopathic pulmonary arterial hypertension.

The usual differential diagnoses of nocturnal events in children include parasomnias, nocturnal seizures, nocturnal reflux (Sandifer syndrome), hypnic jerks, periodic limb movements of sleep, and sleep disordered breathing. We report a previously healthy young girl who presented to the sleep clinic for evaluation of nocturnal events which were diagnosed as medically refractory nocturnal seizures. It was not until a syncopal event occurred in the daytime, which prompted referral for cardiac evaluation, the diagnosis of idiopathic pulmonary arterial hyper-tension (IPAH) was made. Sleep physicians should consider IPAH in the differential diagnosis of nocturnal events in children.