Sobredosis accidental de enoxaparina en un recién nacido / Enoxaparin overdose in a newborn

La enoxaparina es una heparina de bajo peso molecular utilizada en el período neonatal. Requiere menor monitoreo que la heparina estándar o no fraccionada, si bien es escaso el conocimiento actual acerca de su dosis y de los niveles terapéuticos en los neonatos. Además, existe una información muy limitada respecto del manejo de su sobredosificación en este grupo de edad. Se presenta el primer caso publicado en castellano de un neonato que recibió una dosis de enoxaparina diez veces superior a la terapéutica de forma accidental y en el que se administró una dosis aislada de protamina para revertir su efecto.

Enoxaparin is a low molecular weight heparin used in the neonatal period. It requires less monitoring than standard or unfractionated heparin, although current knowledge about its dose and therapeutic levels in neonates is scarce. In addition, there is very limited information about the management of overdose in this age group. We present the first case published in Spanish of a neonate who accidentally received a dose of enoxaparin ten times higher than the therapeutic one and an isolated dose of protamine to reverse its effect.

[Enoxaparin overdose in a newborn]. / Sobredosis accidental de enoxaparina en un recién nacido.

Enoxaparin is a low molecular weight heparin used in the neonatal period. It requires less monitoring than standard or unfractionated heparin, although current knowledge about its dose and therapeutic levels in neonates is scarce. In addition, there is very limited information about the management of overdose in this age group. We present the first case published in Spanish of a neonate who accidentally received a dose of enoxaparin ten times higher than the therapeutic one and an isolated dose of protamine to reverse its effect.

La enoxaparina es una heparina de bajo peso molecular utilizada en el período neonatal. Requiere menor monitoreo que la heparina estándar o no fraccionada, si bien es escaso el conocimiento actual acerca de su dosis y de los niveles terapéuticos en los neonatos. Además, existe una información muy limitada respecto del manejo de su sobredosificación en este grupo de edad. Se presenta el primer caso publicado en castellano de un neonato que recibió una dosis de enoxaparina diez veces superior a la terapéutica de forma accidental y en el que se administró una dosis aislada de protamina para revertir su efecto.

Low-molecular-weight heparin overdose: management by observation.

OBJECTIVE: To describe 3 episodes of low-molecular-weight heparin (LMWH) overdose in 2 patients and discuss the clinical presentations, outcomes, and therapeutic options. CASE SUMMARIES: The first patient, a 35-year-old female, presented after an intentional overdose of 72,000 units of dalteparin. The peak measured anti-Xa activity was 6.2 U/mL at 7.5 hours postinjection. No interventions were performed and there were no bleeding complications. The patient presented 20 days later following another overdose of 72,000 units. Anti-Xa activity was 4.5 U/mL 2 hours postinjection. No treatment was given and the patient was discharged with plans for follow-up the next day. There was no evidence of bleeding complications on follow-up. The second patient, a 29-year-old male, presented after an intentional overdose of 480 mg of enoxaparin. The anti-Xa activity was 1.9 U/mL measured 2 hours postinjection. The patient was observed without intervention. There were no bleeding complications. DISCUSSION: To our knowledge, there is only one previous report of an LMWH overdose in the literature, an iatrogenic overdose in an infant treated with protamine. In our 3 presented episodes of LMWH overdose, no therapeutic interventions were performed and there were no bleeding complications. Review of the literature regarding the efficacy of protamine and recombinant factor VIIa for reversal of LMWH coagulopathy revealed that protamine is only partially effective and recombinant factor VIIa is effective in in vitro studies and case reports. CONCLUSIONS: In cases of LMWH overdose, observation seems to be appropriate in the absence of clinically significant bleeding. Prolonged monitoring may be necessary for patients with renal failure. Use of protamine or recombinant factor VIIa is not supported by this case series in patients without significant bleeding. There is a lack of data regarding how to treat patients with significant bleeding.

Case files of the Medical Toxicology Fellowship at Banner Good Samaritan Medical Center in Phoenix, AZ: a non-warfarin anticoagulant overdose.

A 50-year-old man presented to the emergency department (ED) following an overdose of his "blood thinners." The patient had become increasingly depressed over financial concerns, prompting a suicide attempt. He declined to provide any details regarding his current medications or his past medical history. A review of the computerized medical record, however, revealed he had a Factor V Leiden mutation with multiple venothromboembolic events. He previously had an inferior vena cava filter placed, and had received tissue plasminogen activator (tPA) for a cerebrovascular accident. A toxicology consult was obtained in the ED.

Bleeding the system: a case of feigned enoxaparin overdose.

BACKGROUND: Low-molecular-weight heparins (LMWHs) have become ubiquitously used as anticoagulants because of their comparative safety and ease of use; however they may be fatal if taken in overdose, and lack of familiarity with their pharmacology may hinder appropriate care. OBJECTIVE: The author reports a case of feigned LMWH overdose so as to alert practitioners to this diagnostic possibility. METHOD: This is a case report of a 49-year-old homeless man who reported a deliberate overdose of an injectable LMWH. The author reviews the mechanism of action and monitoring of LMWHs. RESULTS: On the basis of his unusual presentation and previously documented history and medical work-up, he was ultimately diagnosed with malingering. DISCUSSION: Feigned LMWH overdose is ideally suited to the purposes of malingering, since it represents a medical emergency that requires inpatient medical hospitalization and testing at outside laboratory facilities to verify the overdose.

Incomplete reversal of enoxaparin toxicity by protamine: implications of renal insufficiency, obesity, and low molecular weight heparin sulfate content.

The use of low molecular weight heparin (LMWH) is increasing throughout North America and Europe for a number of reasons: 1). ease of use; 2). predictable dose response; 3). less heparin associated thrombocytopenia. However, aside from increased costs, LMWH has significant potential drawbacks: 1). poor reversibility; 2). tendency to accumulate in renal insufficiency; 3). less experience in subset patient groups such as morbid obesity. We report a case of a postoperative morbidly obese patient who developed enoxaparin toxicity secondary to acute renal failure that did not reverse with protamine sulfate infusion. In addition, we review the use of LMWH in renal insufficiency, dosing in obese patients,and the importance of sulfate content in the efficacy of protamine sulfate as a reversing agent for LMWH.