A 64-year-old man is evaluated in the hospital prior to the planned placement of a tunneled hemodialysis catheter. He has a history of end-stage renal disease secondary to diabetic nephropathy and currently receives hemodialysis via a temporary right internal jugular venous catheter. Over the past 48 hours, the nursing staff has noted persistent oozing of blood from the catheter insertion site. His current medications include amlodipine, sevelamer, and erythropoietin. Vital signs are within normal limits. Laboratory studies reveal the following:
| Test | Value |
|---|---|
| Hemoglobin | |
| Platelet count | |
| Blood urea nitrogen | |
| Serum creatinine | |
| Prothrombin time (PT) | |
| Partial thromboplastin time (aPTT) |
Which of the following is the most appropriate pharmacologic intervention to reduce this patient's bleeding risk before the upcoming procedure?
- Intravenous desmopressinCevap
- BPlatelet transfusion
- CFresh frozen plasma
- DVitamin K supplementation
- EProtamine sulfate
Cevap
Intravenous desmopressin
This patient is presenting with uremic platelet dysfunction, characterized by abnormal bleeding (e.g., oozing from catheter sites) in the setting of elevated blood urea nitrogen (BUN) and uremic toxins. In uremia, the circulating toxins interfere with platelet adhesion and aggregation, leading to a prolonged bleeding time despite a normal platelet count, normal prothrombin time (PT), and normal partial thromboplastin time (aPTT). Intravenous desmopressin (DDAVP) is the most appropriate pharmacologic intervention to rapidly improve hemostasis. Desmopressin stimulates the release of von Willebrand factor (vWF) and factor VIII from endothelial cell Weibel-Palade bodies, which facilitates platelet adhesion to the injured endothelium and transiently corrects the bleeding defect.
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Anahtar Kavram
Uremic platelet dysfunction causes abnormal bleeding with a normal platelet count, PT, and aPTT; it is acutely managed with desmopressin (DDAVP) prior to invasive procedures.