Central venous catheter-related blood stream infections in patients receiving intravenous iloprost for pulmonary hypertension

Incidence of Bloodstream Infection in Patients with Pulmonary Hypertension under Intravenous Epoprostenol or Iloprost—A Multicentre, Retrospective Study

Intravenous synthetic prostacyclin analogs (iPCAs), such as epoprostenol, treprostinil and iloprost have been widely used for the treatment of pulmonary arterial hypertension (PAH). Despite having good outcomes, continuous infusion of iPCAs has been associated with some adverse effects. Bloodstream infection (BSI) is one of the most severe complications, although poorly recognized, especially under iloprost administration, which few studies have addressed. This study aimed to compare the BSI incidence rates between intravenous iloprost and epoprostenol administration. Patients with pulmonary hypertension (PH) functional class III or IV receiving intravenous iloprost or epoprostenol through Hickman catheter, between 2004 and 2019, were retrospectively selected from two PH treatment centers. From a total of 36 patients (13 for iloprost and 23 for epoprostenol), 75% (n = 27) fulfilled the PAH criteria, mainly belonging to the idiopathic group. Overall BSI rate was 1.5/1000 days of treatment (3.38 and 0.09/1000 days for iloprost and epoprostenol, respectively). Patients receiving iloprost were at a higher risk of developing BSI than those receiving epoprostenol (HR: 12.5; 95% CI: 1.569–99.092). A higher mortality rate from BSI was also identified in the iloprost group (p = 0.04). Twenty-seven patients developed BSI, with 92% of them requiring hospitalization. A total of 29 agents were found, 10 Gram-positive (mainly Staphylococcus aureus; n = 5) and 19 Gram-negative (mainly Pseudomonas aeruginosa; n = 6) bacteria. Iloprost administration was linked to a significantly higher incidence of BSI, worse prognosis, and more BSI-related deaths than epoprostenol. BSI due to Gram-negative, commensal, low-virulence bacteria was also higher in the iloprost group. In short, physicians should be aware when prescribing iPCA to guarantee their patients’ safety and best medical care.

Complications associated with peripherally inserted central catheters and Hickman™ in patients with advanced pulmonary hypertension treated with intravenous prostanoids

BACKGROUND

Epoprostenol requires continuous infusion and may lead to catheter-related complications. Evidence regarding the comparison between peripherally inserted central catheters (PICC) or tunneled central catheters in Pulmonary Hypertension (PH) is scarce. We sought to study the incidence of mechanical and infectious complications associated with PICC and Hickman catheters in patients with PH under epoprostenol treatment.

METHODS

This is a single-center retrospective study of patients with PH who received continuous treatment with intravenous epoprostenol for at least 24 h between January 2010 and July 2020. Mechanical and infectious complications were analyzed according to the catheter type: PICC and Hickman. The incidence of catheter-related complications was calculated per 1000 exposure-days of risk.

RESULTS

175 catheters were implanted in 109 patients, of which 100 (57.1%) were Hickman and 75 (42.9%) were PICC. After a median follow-up of 334 [130-798] days, there were no differences in the rates of local (0.22 vs 0.21; p = 0.904) or blood-stream infections (0.13 vs 0.21; p = 0.405). Mechanical complications were more frequent in the PICC group (0.98 vs 0.23 p=<0.001), including venous thrombosis (0.16 vs 0.00 p = 0.003) and catheter occlusion (0.66 vs 0.04 p=<0.001). These complications were associated with a greater need for hospitalization (1.48 vs 0.50; p=<0.001), without differences in mortality during follow-up (0.33 vs 0.21; p = 0.288).

CONCLUSION

In patients with PH treated with intravenous epoprostenol, both Hickman and PICC catheters were associated with high rate of complications. Although there were no differences in the frequency of infectious-related complications, PICC was associated with a higher frequency of catheter occlusion and deep venous thrombosis.

Successful use of intravenous treprostinil as a bridge to pulmonary thromboendarterectomy

Chronic thromboembolic pulmonary hypertension (CTEPH) involves non-resolving thromboemboli in the pulmonary arteries. Treatment for CTEPH includes lifelong anticoagulation and determination of patients who have disease which is operable versus inoperable. Pulmonary arterial hypertension (PAH) targeted therapies are oftentimes used as a bridge to pulmonary thromboendarterectomy (PTE), though riociguat is the only Food and Drug Administration (FDA)-approved therapy for CTEPH. There is a paucity of data regarding the efficacy of other PAH therapies, particularly as a bridge to PTE. Here, we present a case report of severe CTEPH related to ventriculoatrial shunt in which intravenous treprostinil was used as a bridge to PTE.

Intravenous prostacyclin-analogue therapy in pulmonary arterial hypertension - A review of the past, present and future

Therapy with intravenous prostacyclin analogues in patients with pulmonary arterial hypertension (PAH) has been established for decades and is an integral component of the current guidelines for the treatment of pulmonary hypertension. Initially, these drugs were infused by external pump systems via tunnelled right atrial catheters with the need for cooling and frequent exchange of drug reservoirs. Associated complications included, among others, catheter-related infections. More recently, fully implantable pump systems have been developed with drug reservoirs that are filled transcutaneously, allowing intervals between refills of several weeks. This technique results in a low rate of infections. Epoprostenol, iloprost and treprostinil have all been used intravenously in PAH, but titration, dosing and dose escalation in long-term therapy are not standardized. Intravenous prostacyclin analogues are still under-used, despite available data suggesting that early and broad application of these therapies as part of risk-oriented, guideline-directed combination therapy for patients with PAH may lead to a survival benefit. This review provides a detailed overview of the drugs, infusion systems and dosing strategies used for intravenous therapy in patients with PAH.

Use of Treprostinil in Pediatric Pulmonary Hypertension: Case Reports and Review of the Literature

BACKGROUND

Add-on therapy with prostacyclin in pediatric refractory pulmonary hypertension (PH) poses a challenge, especially when considering continuous intravenous administration in younger children. A search for alternate routes of drug delivery has led to the clinical investigation of stable and long-acting prostacyclin analogues, such as subcutaneous treprostinil. We reported 2 pediatric cases of PH treated with subcutaneous treprostinil and reviewed the literature on treprostinil use in children.

METHOD

The literature review used 3 electronic databases and a combination of terms (treprostinil, pediatric, PH, prostanoid, etc). We also searched for pediatric clinical trials on treprostinil registered on international clinical trial registries.

RESULTS

The reported cases highlighted the multifactorial nature of PH in pediatrics: a female child with a giant omphalocele, and intracardiac and extracardiac shunts; and a male premature child with a congenital diaphragmatic hernia and long-term PH. The literature review identified 19 studies reporting treprostinil use in 421 children with various types of PH (groups 1 and 3). Subcutaneous treprostinil was the most administered formulation, at a mean dose of 40 ng/kg/min. Overall, 12 clinical trials on treprostinil for children with PH were registered on the clinical trial registries. Most authors concluded that subcutaneous treprostinil was effective, well tolerated, and represented an alternative to intravenous epoprostenol.

CONCLUSIONS

Subcutaneous treprostinil may be a useful adjunct in the therapeutic algorithm for children with severe PH, refractory to oral drugs, and after a complete check-up for all PH etiologies.

[Tunnelled central venous catheter infection during treatment with epoprostenol]

INTRODUCTION

Pulmonary arterial hypertension is a pulmonary vascular disease with a poor prognosis. Continuous intravenous treatment with prostacyclin analogues requires the placement of a tunnelled catheter. The occurrence of catheter-related infections in this context is unusual due to the alkaline pH of the prostacyclin analogue solutions.

OBSERVATION

A 50-year-old patient with inherited pulmonary artery hypertension, treated with bosentan, sildenafil and epoprostenol, experienced generalized malaise associated with a weight loss of 9kg over a 12-month period without evidence of a source of infection or malignancy. There was no evidence of hemodynamic disturbance. The diagnosis was made after 1 year of follow-up, when the patient presented with a 38° fever and a biological inflammatory syndrome. Repeated peripheral blood cultures were positive for Dietzia, an alkalophilic coryneform bacillus. The patient's condition responded favourably to antibiotic therapy.

CONCLUSION

Infection of a tunneled intravenous catheter should be considered in the case of non-specific symptoms or where there is evidence of sepsis, in patients treated with intravenous prostacyclin analogues administered intravenously. In this context, the laboratory should be warned to search for slow-growing organisms.

Central line replacement following infection does not improve reinfection rates in pediatric pulmonary hypertension patients receiving intravenous prostanoid therapy

Treatment of pediatric pulmonary hypertension (PH) with IV prostanoids has greatly improved outcomes but requires a central line, posing inherent infection risk. This study examines the types of infections, infection rates, and importantly the effect of line management strategies on reinfection in children receiving IV prostanoids for PH. This study is a retrospective review of all pediatric PH patients receiving intravenous epoprostenol (EPO) or treprostinil (TRE) at one academic tertiary care center between 2000 and 2014. No patients declined participation in the study or were otherwise excluded. Infectious complications were characterized by organism(s), infection rates, time to next infection, and line management decisions (salvage vs. replace). Of the 40 patients followed, 13 sustained 38 infections involving 49 pathogens, with a predominance of gram-positive (GP) organisms (n = 35). The pooled infection rate was 1.06 per 1000 prostanoid days with no difference between EPO and TRE. No significant difference in reinfection rate was observed when comparing line salvage to replacement, regardless of organism type. Both overall and organism-type comparisons suggest longer time between line infections following line salvage compared with line replacement (732 vs. 410 days overall; 793 vs. 363 days for GP; 611 vs. 581 days for gram-negative [GN]; P > 0.05 for all comparisons). Central line replacement following blood stream infections in pediatric PH patients does not improve subsequent infection rates or time to next infection, and may lead to unnecessary risks associated with line replacement, including potential loss of vascular access. A revised approach to central line infections in pediatric PH is proposed.

Incidence and risk of respiratory tract infection associated with specific drug therapy in pulmonary arterial hypertension: a systematic review

Specific drug therapy has been proven to improve functional capacity and slow disease progression in pulmonary arterial hypertension (PAH), regretfully with the data on the risk of respiratory tract infection (RTI) associated with specific drug therapy being limited. Databases of Medline, Embase, Cochrane Library and the ClinicalTrials.gov Website were searched for randomized controlled trials (RCTs) that reported the RTI data of PAH-specific drug therapy in patients. The primacy outcome was assessed by employing a fixed-effects model. Totally, 24 trials involving 6307 patients were included in the analysis. PAH-specific drug therapy was not significantly associated with the increased risk of both RTI (19.4% vs. 21.1% RR 1.02, 95%CI 0.92-1.14, P = 0.69) and serious RTI (4.3% vs. 5.0% RR 0.99, 95%CI 0.77-1.26, P = 0.93) compared to placebo. The results were consistent across the key subgroups. No heterogeneity between the studies (I2 = 35.8% for RTI, and I2 = 0.0% for serious RTI) and no publication bias was identified. In conclusion, no significant increase in RTI had been found in PAH-specific drug therapy when compared with placebo. Whereas, RTI in PAH patients is still worthy of clinical attention.

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.