Compartment syndrome in an ELBW infant receiving low-molecular-weight heparins

Short term outcome of neonatal venous thromboembolism in anticoagulated versus observed patients

BACKGROUND

Advancements in the medical field and increased survival of premature infants have led to a rise of venous thromboembolism (VTE) in neonates. Neonatal hemostasis exists in a delicate balance with a propensity towards pro-coagulation. Current recommendations include careful observation, therapeutic anti-coagulation and in some cases thrombolysis. We hypothesize that a sub-group of neonates may not require anti-coagulation and could be safely observed thus reducing their risk of bleeding complications.

METHODS

We conducted a retrospective chart review of patients with VTE admitted to the neonatal intensive care unit at the Oklahoma University Children's Hospital from October 2009-October 2019. Patients were selected if they had an ICD-9 or ICD-10 code specific for a VTE or if screening with CPT codes for diagnostic imaging including echocardiogram, venous dopplers and computed topographic/magnetic resonance venogram revealed the word 'thrombus', 'clot' or 'venous thromboembolism'. Data were collected about demographics, medical history, co-morbidities, thrombosis characteristics, treatment and outcome.

RESULTS

A total of 211 patients were screened and 119 patients were eligible and included in the study. The majority of patients (85 %) had a central venous catheter (CVC) associated VTE. Two-thirds of patients (n = 81, 68 %) received therapeutic anti-coagulation while one-third (n = 38, 32 %) were observed. The group that received anticoagulation had a significantly older age at diagnosis and had a higher frequency of bacteremia, congenital heart disease and presence of symptoms. There was no difference in the odds of complete resolution between patients who were treated with therapeutic anti-coagulation and those that were observed (OR: 1.37, 95 % CI: 0.59-3.20, p-value: 0.47). Univariate analysis revealed maternal preeclampsia (OR: 0.2, 95 % CI: 0.05-0.82, p-value = 0.025), maternal history of chronic hypertension (OR: 0.17, 95 % CI: 0.04-0.68, p-value = 0.01), and presence of complete occlusion (OR = 0.37, 95 % CI: 0.15-0.91, p-value = 0.03) significantly reduced the odds of complete resolution. Furthermore, having a VTE related to a CVC in an extremity versus an ECMO cannula or cardiac catheterization significantly improved the odds of VTE resolution (OR = 5.94, 95 % CI: 1.30-27.20, p-value = 0.022). Using a stepwise regression model, maternal history of chronic hypertension remained significant for a reduced odds of VTE resolution (OR: 0.14, 95 % CI 0.025-0.73, p-value: 0.02).

CONCLUSIONS

The short-term outcome of neonatal VTE does not seem to differ between those that were anticoagulated and those that were observed with serial imaging.

Compartment syndrome associations with drugs: a pharmacovigilance study of the FDA adverse event reporting system (FAERS)

BACKGROUND

Compartment syndrome is an uncommon but life-threatening condition. No study has comprehensively compared compartment syndrome (CS) association with available drugs. The objective of this study was to estimate the association between CS and drugs using the FDA Adverse Event Report System (FAERS).

RESEARCH DESIGN AND METHODS

FAERS reports from the first quarter of 2004 to the third quarter of 2023 were analyzed. The Medical Dictionary for Regulatory Activities (MedDRA) was used to identify CS cases. Reporting odds ratio (ROR), corresponding to 95% confidence intervals (95% CI) were calculated to detect a positive signal.

RESULTS

A total of 2197 reports were considered in the study after the inclusion criteria were applied. Totally 100 drugs were found to be associated with CS. The median time for drug-associated CS was 45 days.

CONCLUSIONS

By analyzing the FAERS database, the study revealed that certain drugs are significantly associated with compartment syndrome. Further studies are needed to verify whether these drugs are associated with such a risk.

Severe hematoma following the use of low molecular weight heparin in preterm neonate

Objectives

With the increased survival of preterm neonates, thromboembolic (TE) events are increasingly being recognized due to the use of indwelling catheters. It is still debatable to treat TE with low molecular weight heparin (LMWH) or follow expectant management. Despite the safety and efficacy profile about using LMWH in adults, its use in extreme preterm neonates with TE events is limited. The therapeutic level and pharmacokinetics of LMWH in the preterm population are relatively variable.

Case presentation

We present a case with a severe hematoma on the left thigh following the use of LMWH, which was surgically drained and had a successful skin graft.

Conclusions

This case highlights the importance of early and close monitoring of injection sites in patients treated with LMWH.

Entrapped peripherally inserted central catheter due to fibrin sheath in a neonate with noninvasive extraction and review of literature

Peripherally inserted central catheter line entrapment is a rare complication in the neonatal intensive care unit and only a small number of cases have been reported. While studies have suggested recommendations for removal, there is still a need for surgical intervention in some cases. This is a case of a premature infant with long term peripherally inserted central catheter line placement with fibrin sheath formation that required multiple attempts before successful noninvasive removal and a review of the cases with difficult peripherally inserted central catheter removal in newborns.

Effectiveness and Safety of Nadroparin Therapy in Preterm and Term Neonates with Venous Thromboembolism

INTRODUCTION

Optimal neonatal nadroparin dosages to treat venous thromboembolism (VTE) are unknown.

OBJECTIVE

To evaluate therapeutic nadroparin dosages to reach therapeutic target ranges (TTR: 0.5-1.0 International Unit (IU)/mL) and the effectiveness and safety of nadroparin in neonatal VTE.

METHODS

Retrospective study including neonates with VTE on nadroparin in a tertiary center between 2007 and 2018. Two groups were distinguished: neonates before (group 1) and after (group 2) switch to higher starting dosages in 2014.

RESULTS

Sixty-one neonates (44 preterm, 17 term) with 64 VTEs were included. TTR was reached in 32/64 (50%) VTEs (group 1: 35.7%; group 2: 61.1%). Median nadroparin dosage to reach TTR was 197 (97.9-330.3) IU/kg/12 h. No therapy-related deaths occurred. Recurrent VTE developed in 6 (9.8%) neonates. Complete clot resolution was observed in 31/41 (75.6%) VTEs. TTR was reached in 58.1% VTEs with complete clot resolution. No major bleeding occurred. Non-major clinically relevant bleedings occurred in 3/64 (4.7%) VTEs, consisting of large hematomas due to the use of subcutaneous catheters.

CONCLUSIONS

High nadroparin dosages are needed to reach TTR in neonates, which seem to be safe. Clot resolution may occur without reaching TTR. Subcutaneous catheters may cause important bleeding complications.

Heparin for the treatment of thrombosis in neonates

BACKGROUND

Among pediatric patients, newborns are at highest risk of developing thromboembolism. Neonatal thromboembolic (TE) events may consist of both venous and arterial thromboses and often iatrogenic complications (eg, central catheterization). Treatment guidelines for pediatric patients with TE events most often are extrapolated from the literature regarding adults. Options for the management of neonatal TE events include expectant management; nitroglycerin ointment; thrombolytic therapy or anticoagulant therapy, or a combination of the two; and surgery. Since the 1990s, low molecular weight heparin (LMWH) has become the neonatal anticoagulant of choice. Reasons for its appeal include predictable dose response, no need for venous access, and limited monitoring requirements. The overall major complication rate is around 5%. Whether preterm infants are at increased risk is unclear. No data are available on the frequency of osteoporosis, heparin-induced thrombocytopenia (HIT), or other hypersensitivity reactions in children and neonates exposed to LMWH.

OBJECTIVES

To assess whether heparin treatment (both unfractionated heparin [UFH] and LMWH) reduces mortality and morbidity rates in preterm and term newborn infants with diagnosed thrombosis. The intervention is compared with placebo or no treatment. Also, to assess the safety of heparin therapy (both UFH and LMWH) for potential harms.Subgroup analyses were planned to examine gestational age, birth weight, mode of thrombus diagnosis, presence of a central line, positive family history for genetic disorders (thrombophilia, deficiency of protein S and protein C, methylenetetrahydrofolate reductase [MTHFR] mutation), route of heparin administration, type of heparin used, and location of thrombus (see "Subgroup analysis and investigation of heterogeneity").

SEARCH METHODS

We used the standard search strategy of the Cochrane Neonatal Review Group to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 4), MEDLINE via PubMed (1966 to May 9, 2016), Embase (1980 to May 9, 2016), and the Cumulative Index to Nursing and Allied Health Literature (CINAHL; 1982 to May 9, 2016). We searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomized controlled trials and quasi-randomized trials.

SELECTION CRITERIA

Randomized, quasi-randomized, and cluster-randomized controlled trials comparing heparin versus placebo or no treatment in preterm and term neonates with a diagnosis of thrombosis.

DATA COLLECTION AND ANALYSIS

We used the standard methods of the Cochrane Neonatal Review Group. Two review authors independently assessed studies identified by the search strategy for inclusion.

MAIN RESULTS

Our search strategy yielded 1160 references. Two review authors independently assessed all references for inclusion. We found no completed studies and no ongoing trials for inclusion.

AUTHORS' CONCLUSIONS

We found no studies that met our inclusion criteria and no evidence from randomized controlled trials to recommend or refute the use of heparin for treatment of neonates with thrombosis.

Thrombosis in the Neonatal Intensive Care Unit

Neonates have the highest risk for pathologic thrombosis among pediatric patients. A combination of genetic and acquired risk factors significantly contributes to this risk, with the most important risk factor being the use of central venous catheters. Proper imaging is critical for confirming the diagnosis. Despite a significant number of these events being life- and limb-threatening, there is limited evidence on what the appropriate management strategy should be. Evaluation and treatment of any neonate with a clinically significant thrombosis should occur at a tertiary referral center that has proper support.

A practical approach to the use of low molecular weight heparins in VTE treatment and prophylaxis in children and newborns

Low-molecular weight heparins are currently the most commonly used anticoagulants in children and newborns. However, since thrombotic complications rarely occur outside large children's hospitals, physicians often encounter some practical problems in managing these treatments when a pediatric thrombosis specialist is not available. The drug of choice is enoxaparin, due to its favorable FXa/FIIa ratio and the availability of pharmacokinetic and pharmacodynamic data. The treatment of acute thrombosis should be started with two daily injections but when compliance is an issue, a single daily administration schedule could be chosen for secondary prophylaxis ensuring careful measurement of the post 24-hour anti-FXa activity. Furthermore, a subcutaneous device may be a useful tool and a topical dermal anesthetic could be effective in controlling pain without affecting anti-FXa levels. In neonate and toddlers, where mini doses are frequently needed, the dead space of syringes and needles could represent an issue and therefore the use of insulin syringes without dead space is advisable, while a dilution of the drug is useful with other syringes. This article derives from a nonsystematic review of the available literature, with special attention to recent international guidelines and expert recommendations, combined to authors' clinical practice in large tertiary pediatric hospitals and will provide concise and practical information for the use of low-molecular weight heparin in childhood and infancy in a sort of "answering frequently asked questions."

Retrospective evaluation of enoxaparin dosing in patients 48 weeks' postmenstrual age or younger in a neonatal intensive care unit

BACKGROUND

Enoxaparin is the anticoagulant of choice in neonates because of the ease of administration, predictable pharmacokinetics, and reduced adverse effects when compared to heparin. The Chest guidelines recommend that therapy in patients younger than 2 months should be initiated with enoxaparin 1.5 mg/kg administered subcutaneously twice daily. This starting dosage may be inadequate, leading to a delay in achieving therapeutic anti-factor Xa plasma concentrations.

OBJECTIVE

To determine an enoxaparin dose for neonatal patients that achieves a therapeutic anti-factor Xa plasma concentration and compare that dose to the recommended enoxaparin dose per published guidelines for this patient population.

METHODS

The study was designed as a single-center chart review. Eligible patients were identified by pharmacy anticoagulation records or a search of the electronic medical record for enoxaparin orders. Patients must have received enoxaparin subcutaneously twice daily and have had a postmenstrual age of 48 weeks or younger. Patients diagnosed with renal failure and those receiving prophylactic doses of enoxaparin were excluded.

RESULTS

The mean (SD) initial dose of enoxaparin was 1.4 (0.3) mg/kg subcutaneously twice daily, resulting in 27 of 33 patients (81.8%) having a subtherapeutic anti-factor Xa concentration. A mean enoxaparin dose of 2.0 (0.5) mg/kg was required to achieve a therapeutic anti-factor Xa plasma concentration (p < 0.001). Patients born prematurely required a higher enoxaparin dose (2.2 [0.5] mg/kg) than did those born at full-term gestation (1.8 [0.4] mg/kg; p < 0.05).

CONCLUSIONS

For patients 48 weeks' postmenstrual age or younger who are treated in a neonatal intensive care unit, a higher initial dose of enoxaparin than that suggested by the Chest guidelines is required to attain a therapeutic antifactor Xa plasma concentration. Premature neonates require a larger starting dose of enoxaparin than do infants born at full-term gestation.

Management of neonatal thrombosis

Neonates have one of the highest risks for thromboembolism among pediatric patients. This risk is attributable to a combination of multiple genetic and acquired risk factors. Despite a significant number of these events being either life threatening or limb threatening, there is limited evidence on appropriate management strategy. Most of what is recommended is based on uncontrolled studies, case series, or expert opinion. This review begins with a discussion of the neonatal hemostatic system, focusing on the common sites and imaging modalities for the detection of neonatal thrombosis. Perinatal and postnatal risk factors are presented and management options discussed.

Management and outcome in 32 neonates with thrombotic events

Objective. To determine the incidence, management, complications, and outcome in neonates with thrombotic events. Study Design. We performed a retrospective study of all neonates with thrombotic events admitted to our neonatal intensive care unit from January 2004 to July 2010. Results. Thrombotic events were identified in 32 of 4734 neonates (0.7%). Seven neonates were managed expectantly and 25 neonates received anticoagulant treatment. Complete resolution of the clot within 3 months of age was found in 68% (17/25) of the treated and in 86% (6/7) of the nontreated neonates. Major complications due to anticoagulant therapy occurred in 3/25 cases (12%) and included severe hemorrhage (n = 2) and abscess at the injection site (n = 1). Conclusion. Complete or partial clot resolution in neonatal thrombosis occurred in both the treated group and nontreated group. Randomized controlled trials are warranted to determine the optimal management in neonatal thrombosis.

Aspects of anticoagulation in children

The number of children receiving anticoagulation is increasing. Thromboembolic events are associated with significant risk of morbidity and mortality although the optimal management of asymptomatic events remains unclear. Specific challenges in paediatrics include the diagnosis of thrombosis, delivery and monitoring of anticoagulation in a wide range of ages from neonates through to adolescents. The development of the haemostatic system as children age results in changing pathophysiology of thrombosis and response to anticoagulation agents. Although registry and observational studies have provided vital information, specific paediatric, prospective anticoagulation studies have been few and limited in design. The result is that much of current practice is extrapolated from adult studies. Traditional anticoagulants have significant limitations. Both heparin and warfarin are in widespread use but many fundamental questions regarding dose, therapeutic range, efficacy and optimum duration have not been fully answered. Alternative agents, such as direct thrombin inhibitors and the selective anti-factor Xa inhibitor fondaparinux, may have advantages for children. Clinical trials in adults and preliminary data in children are promising but caution should be applied until specific paediatric studies have demonstrated safety and efficacy.

Outcome of cardiac thrombi in infants

Use of central lines in the neonatal intensive care unit (NICU) has led to the formation of intracardiac thrombi. A paucity of data exists on the management of neonatal cardiac thrombi, with the few reported cases focusing on outcomes following thrombolytic therapy. This study was undertaken to evaluate the outcome of cardiac thrombi in neonates who do not receive thrombolytic therapy. Nineteen patients younger than 3 months of age diagnosed with cardiac thrombi were included. All 19 patients had a central line. Management consisted of a combination of antibiotics and low-molecular-weight heparin (n = 16) or surgical removal (n = 2). In one case, no treatment was instituted. One patient was lost to follow-up after partial resolution of the thrombus. Complete thrombus resolution occurred in 18 patients, 9 with negative blood cultures and 9 with positive blood cultures. It took longer for resolution of thrombi associated with positive blood cultures than for sterile thrombi. No patient had evidence of thrombus embolization. From these data we concluded that the natural history of cardiac thrombi is resolution. Infected thrombi require more prolonged therapy. Surgery is seldom required and thrombolytics are not usually necessary for clot resolution.

Enoxaparin Use in the Neonatal Intensive Care Unit: Experience Over 8 Years

STUDY OBJECTIVE

To evaluate the effectiveness and safety of enoxaparin therapy in a neonatal intensive care unit (NICU).

DESIGN

Retrospective chart review.

SETTING

Level III NICU in a Canadian academic center.

PATIENTS

All neonates treated with enoxaparin while in the NICU between January 1, 1998, and June 1, 2006.

MEASUREMENTS AND MAIN RESULTS

Data abstracted included patient demographics, diagnosis of thrombosis and its progression, enoxaparin dosages with corresponding antifactor Xa levels, and adverse events. Sixteen neonates (four term, 12 preterm) were treated with enoxaparin at a mean +/- SD initial subcutaneous dose of 1.41 +/- 0.15 mg/kg every 12 hours. The target therapeutic range (antifactor Xa level 0.5-1.0 U/ml) was achieved by 12 infants at a mean +/- SD dose of 1.92 +/- 0.43 mg/kg every 12 hours, after a mean of 5.6 days (range 1-15 days). Preterm infants required a higher dose (per kilogram) compared with term infants to maintain therapeutic antifactor Xa levels (mean +/- SD 1.94 +/- 0.39 vs 1.65 +/- 0.14 mg/kg every 12 hrs, p<0.001). Enoxaparin doses were more strongly correlated to antifactor Xa levels in term infants (r(2)=0.51, p<0.001) compared with preterm infants (r(2)=0.20, p<0.001). Ten (71%) of 14 thromboembolic events resolved, either partially or completely, at a mean of 39 days (range 8-61 days) of enoxaparin therapy. Nine infants (56%) experienced minor local adverse effects at the site of the indwelling subcutaneous catheter (induration, bruises, hematomas, or leakage). Systemic adverse events that were possibly related to enoxaparin therapy included osteopenia (one infant), scleral hemorrhage (one), and minor gastrointestinal tract bleeding (three) found in gastric feeding tubes. No adverse effects were associated with antifactor Xa levels greater than 1.0 U/ml.

CONCLUSION

Enoxaparin may be effective in the treatment of neonatal thrombosis. An initial dosage of 1.5 mg/kg every 12 hours is likely inadequate to obtain therapeutic antifactor Xa levels rapidly and differs for term and preterm neonates. Therapeutic levels in preterm infants may be more variable, and the pharmacokinetics of this drug in preterm infants requires further evaluation. Future studies in neonates should prospectively evaluate a higher starting dose of enoxaparin to document effectiveness, acceptance, compliance with treatment guidelines, and adverse effects.

Retained central venous lines in the newborn: report of one case and systematic review of the literature

The use of percutaneously inserted central catheters (PICCs) is an established practice in most NICUs. With the widespread use of these catheters, an increasing number of PICC complications has been reported in neonates. We present one case of a PICC retained and tethered in the vein in a very low birth weight infant, as well as a systematic review of PICC retention cases. Ten previous cases of PICC retention in neonates were found. Among those cases, the most common associated factors were coagulase-negative staphylococcus catheter colonization/bactcremia and long duration of catheterization. Occlusion was not a usefiul sign for predicting catheter retention. Once retention was established, heparin or urokinase instillations were ineffective. Although surgical exploration was sometimes required, firm, continuous traction applied to the catheter over several hours or intermittent, moderately strong pulling maneuvers were successful in 44.4 percent of the cases in which they were performed. Traction did not show major side effects. Our case provides additional support for use of traction as the initial approach in the management of this rare complication.

A spontaneous intramural hematoma of the bowel presenting as obstruction in a child receiving low-molecular-weight heparin

Low-molecular-weight heparin (LMWH) is a safe and effective alternative to unfractionated heparin and coumadin in the treatment and prophylaxis of thrombosis in children. When compared with these more established anticoagulants, it is easier to achieve therapeutic levels and the incidence of hemorrhagic complications is equivalent or lower. In children there is less published experience than in adults, but the low frequency of significant bleeding appears to be similar. The authors describe a child on therapeutic doses of LMWH for a deep vein thrombosis who spontaneously developed an intramural hemorrhage in his small bowel, leading to infarction and a partial bowel resection.