Bleedings caused by warfarin overdose

Abstract

Objectives: Warfarin is used in prophylaxis and treatment of many diseases. Low doses of warfarin increase risk of thrombosis and high doses increase risk of bleeding. In this study, we evaluated patients having warfarin-related bleedings in aspect of demographic data, duration of hospitalization, morbidity and mortality. Materials and methods: Between dates of January 2010 and December 2010, patients with history of using warfarin and complaint of bleeding, whose international normalized ratio (INR) values 6 or above, were evaluated retrospectively. Results: Twenty-three patients (64%) were female, and thirteen (36%) were male with a total number of 36 patients. The mean age is 67.5 years (range 43-84 year). Mean duration of drug use was 37.2 ± 49.7 months with a median value of 24 months. In six patients (16.7%), warfarin use was initiated for the first time, three (8.3%) was going to change a new dose. INR checks on a regular basis in 18 patients (50%) were achieved. Hematuria and hematemesis/melena were the most common forms of admission. Eleven patients (30%) had both erythrocyte (mean 3.8 units) and fresh frozen plasma transfusions. Thirty (83%) patients had fresh frozen plasma transfusions (mean 2.53 units), 19 of them had only fresh frozen plasma. Rate of mortality due to bleeding was 5,5%. The average of length of hospital stay was 3.28 days (range 1-8 days). Conclusions: Warfarin users need careful INR monitoring. Patients should be informed about importance of INR monitoring and potential complications.

Keywords

• Warfarin, overdose, complication, hemorrhage

Bleedings caused by warfarin overdose

Abstract

Amaç: Warfarin birçok hastalık tedavi ve profilaksisinde kullanılmaktadır. Düşük değerlerde tromboz, yüksek değerlerde ise kanama riski artmaktadır. Bu yazıda warfarin doz aşımına bağlı kanamalı olguların demografik verileri, yatış süreleri, morbidite ve mortalite oranlarının değerlendirilmesi amaçlandı. Gereç ve yöntem: Ocak 2010- Aralık 2010 tarihleri arasında kanama şikayeti ile başvuran, INR değeri 6 veya üzeri, warfarin kullanım öyküsü olan hastalar retrospektif olarak değerlendirildi. Bulgular: Hastaların 23'ü (%64) kadın, 13'ü (%36) erkek olmak üzere toplam 36 hasta vardı. Yaş ortalaması 67,5 yıl (değer aralığı 43-84 yıl) idi. Ortalama ilaç kullanım süresi 37.2 ± 49.7 ay olup, ortanca değer 24 ay idi. Hastaların altısında (%16.7) warfarin kullanımına ilk defa başlanılmış iken, üçünde (%8.3) yeni doz değişikliğine gidilmişti. INR kontrolleri düzenli olarak hastaların 18‘inde (%50) gerçekleştirilmişti. Hematüri ve hematemez / melena en sık görülen başvuru şekli idi. On bir hastaya (%30) eritrosit (ortalama 3,8 ünite) ve taze donmuş plazma transfüzyonu, 19 hastaya (%53) sadece taze donmuş plazma olmak üzere toplam 30 hastaya (%83) taze donmuş plazma transfüzyonu (ortalama 2,53 ünite) yapıldı. Kanamaya bağlı mortalite oranı ise % 5,5 olarak saptandı. Ortalama yatış süresi 3,3 gün (değer aralığı 1-8 gün) olarak gerçekleşti. Sonuç: Warfarin kullanan hastalarda INR monitorizasyon dikkatli bir şekilde yapılmalıdır. Hastalara potansiyel komplikasyonlar ve INR takibinin önemi açısından yeterli bilgiler verilmelidir.

Keywords

• Warfarin, doz aşımı, komplikasyon, kanama

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