Journal of Hematology, ISSN 1927-1212 print, 1927-1220 online, Open Access
Article copyright, the authors; Journal compilation copyright, J Hematol and Elmer Press Inc
Journal website http://www.thejh.org

Original Article

Volume 2, Number 2, October 2013, pages 55-63


Experience Always Wins the Day: Measure of Warfarin Anticoagulation Efficiency in the Internal Medicine Clinic

Figures

Figure 1.
Figure 1. During the 2 weeks follow-up, when using linear interpolation, patient A remains in the therapeutic index (2.0 - 3.0) during 80% of the time (11.2 days) vs patient B who only remains 21% of the time (3 days). Comparatively when using the proportional method, both patients stay in the therapeutic index 67% of the time (2/3 values within 2.0 - 3.0).
Figure 2.
Figure 2. Median proportion of the time at target INR.

Tables

Table 1. Causes of Exclusion From the Study (n = 110)
 
Number of patients (n)
APLS: Antiphospholipid syndrome; HIT: Heparin-induced thrombocytopenia; INR: International normalized ratio; LWMH: Low weight molecular heparine.
Less than 3 INR values25
Auricular fibrillation17
Superficial venous thrombosis11
Use of LWMH11
Lack of data10
Arterial embolic/thrombotic event/APLS7
Outside the study period5
Follow-up done by another service3
No anticoagulation3
Cerebrovascular event3
Retinal thrombosis3
Jugular venous thrombosis2
Portal vein thrombosis2
Digital ischemia1
Sagital sinus thrombosis1
Superior vena cava syndrome1
Mesenteric vein thrombosis1
Warfarin allergy1
HIT1
Surgical repair of patent foramen ovale1
Not present at follow-up1

 

Table 2. Baseline Characteristics of Patients (n = 237)
 
Total n (%)
All data are no. (%) of patients unless otherwise indicated; * Defined by a hemoglobin value < 120 for women and < 140 for men; ** Defined by an elevation any liver function test (LFT) at three times the upper normal limit.
Age mean (range)61 (21 - 97)
Gender (male)112 (47)
Weight mean in kg (range)82.7 (44.4 - 185)
Excessive alcohol consumption8 (3.4)
Chronic kidney disease - GFR < 60 mL/min28 (11.8)
Hepathopathy*6 (2.5)
Hypertension96 (40.5)
Anemia**88 (37.1)
Past medical history of bleeding12 (5.0)
Concomitant use of antiplatelet drugs22 (9.3)
Past history of stroke9 (3.8)
Past history of DVT/PE90 (38)
Active cancer24 (10.1)

 

Table 3. Median Proportion of Time at Target INR Data According to Patient’s Characteristics (n = 237)
 
No of patients (n)No of INR (n)Median follow-up (days)Median proportion of time at target INR 2.0 - 3.0 (%)95% CIP-value
All data are no. of patients unless otherwise indicated; * Defined by a Glomerular Function Rate (GFR) > 60 mL/min; ** Defined by a GFR < 60 mL/min; y.o: Years old.
Overall2372,553250.568.963.1- 69.1NA
Gender
  Women12514232296547 -81
  Men11211303357050 -860.153
Chronic kidney disease
  No*1982,155250.56548 - 83
  Yes**28398356.58072 - 900.048
Age
  < 40 y.o252371015542 -83
  40 - 60 y.o1111,1982496648 -81
  > 60 y.o1011,1182517350 -870.186

 

Table 4. Thrombotic and Haemorrhagic Complications During Follow-Up (n = 17)
 
Type of eventINR at complicationIntervention necessary
AcO: Anticoagulation; ATB: Antibiotics; ENT: Ear-nose-throat; FFP: Fresh frozen plasma; GI: Gastrointestinal; HD: Hemodynamic; IVCF: Inferior vena cava filter; OGD: Oesophageal-gastro-duodenoscopy; PE: Pulmonary embolism; PRBC: Packed red blood cell; UK: unknown.
Thrombotic event
  F87PE2.1None
Minor haemorrhagic event
  F55Macroscopic hematuria2.9Cystoscopy/ureteroscopy/pyelography
  F57EpistaxisUKNone
  M68Hematochezia (anal fissure)2.0None
  F49Iron-deficiency anemia (menorrhagia)UKIntravenous iron repletion
  F52ENT bleeding2.4ENT consultation
  F87EpistaxisUKNone
Major haemorrhagic event
  F59Lower GI bleeding> 9Transfusion/colonoscopy/AcO termination
  F66Upper GI bleeding (H. pylori gastritis)4.1Transfusion (1PRBC)/OGD/ATB/AcO termination
  F79Knee hemarthrosis3.8Vitamin K/surgical drainage/AcO suspension
  M63Upper GI bleeding (gastric cancer)1.1OGD/AcO termination
  M66Lower GI bleedingUKOGD/colonoscopy/arteriography/IVCF/AcO termination
  F87Thigh hematoma with HD instability2.6Transfusion (3PRBC)/AcO termination
  M83Lower GI bleeding (angiodysplasia)2.7Transfusion (2PRBC)/AcO termination
  M64Lower GI bleeding (angiodysplasia)6.3Transfusion (2PRBC and 3FFP)/AcO termination
  F52Lower GI bleeding (haemorrhoid)1.4Vitamin K/colonoscopy/AcO suspension
  M77Post-traumatic leg hematoma4.1Vitamin K/AcO termination at the patient demand