Continuation Of Therapy - Day 5 Forward
-
Target INR for patient who have completed Day 1 - 4 of the initiation protocol:
-
2.5 - 3.5 for patients with mechanical /prosthetic valves or recurrent thrombotic events
-
2 - 3 for all other patients
-
-
Adjust warfarin dose from day 5 forward based on INR response:
-
Medically stable patients without mechanical mitral valves or recurrent thrombotic events target 2 - 3 (see Table 4):
Table 4. Adjusting Warfarin Dose for Days 5 forward for Medically Stable Patients Without Mechanical Mitral Valves or Recurrent Thrombotic Events
|
INR |
Warfarin Adjustment |
|
1.1-1.4 |
Increase dose by 20% |
|
1.5-1.9 |
Increase dose by 10% |
|
2-3 |
No change |
|
3.1-3.5 |
Decrease dose by 10% |
|
>3.5 |
Hold until INR <3.5; restart at 20% less than the previous dose |
-
Mechanical /prosthetic mitral valves or recurrent thrombotic events - target 2.5 - 3.5 (see Table 5):
Table 5. Adjusting Warfarin Dose for Days 5 forward for Mechanical/Prosthetic Mitral Valves or Recurrent Thrombotic Events
|
INR |
Warfarin Adjustment |
|
1.1-1.4 |
Increase dose by 20% |
|
1.5-2.4 |
Increase dose by 10% |
|
2.5-3.5 |
No change |
|
>3.5 |
Hold until INR <3.5; restart at 20% less than the previous dose |
References
Ansell, J., Hirsh, J., Hylek, E., Jacobson, A., Crowther, M., & Palareti, G. (2008). Pharmacology and management of the vitamin K antagonists: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Chest, 133(6 Suppl), 160s-198s. https://doi.org/10.1378/chest.08-0670
Bolton-Maggs, P., & Brook, L. (2002). The use of vitamin K for reversal of over-warfarinization in children. Br J Haematol, 118(3), 924. https://doi.org/10.1046/j.1365-2141.2002.03631_5.x
David, M., et al. (2004, May). Warfarin Therapy in Children. Thrombosis Interest Group of Canada. Retrieved Oct 21, 2008 from http://www.tigc.org/eguidelines/warfarinchildren04.htm.
Horton, J. D., & Bushwick, B. M. (1999). Warfarin therapy: evolving strategies in anticoagulation. Am Fam Physician, 59(3), 635-646.
Lexicomp Online, Pediatric and Neonatal Lexi-Drugs. Warfarin. Retrieved Oct 2008, from https:online.lexi.com.
Monagle, P., Chan, A. K. C., Goldenberg, N. A., Ichord, R. N., Journeycake, J. M., Nowak-Göttl, U., & Vesely, S. K. (2012). Antithrombotic therapy in neonates and children: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Chest, 141(2 Suppl), e737S-e801S. https://doi.org/10.1378/chest.11-2308
Monagle, P., Cuello, C. A., Augustine, C., Bonduel, M., Brandão, L. R., Capman, T., Chan, A. K. C., Hanson, S., Male, C., Meerpohl, J., Newall, F., O'Brien, S. H., Raffini, L., van Ommen, H., Wiernikowski, J., Williams, S., Bhatt, M., Riva, J. J., Roldan, Y., . . . Vesely, S. K. (2018). American Society of Hematology 2018 Guidelines for management of venous thromboembolism: treatment of pediatric venous thromboembolism. Blood Adv, 2(22), 3292-3316. https://doi.org/10.1182/bloodadvances.2018024786
Roach, E. S., Golomb, M. R., Adams, R., Biller, J., Daniels, S., Deveber, G., Ferriero, D., Jones, B. V., Kirkham, F. J., Scott, R. M., & Smith, E. R. (2008). Management of stroke in infants and children: a scientific statement from a Special Writing Group of the American Heart Association Stroke Council and the Council on Cardiovascular Disease in the Young. Stroke, 39(9), 2644-2691. https://doi.org/10.1161/strokeaha.108.189696
These pathways do not establish a standard of care to be followed in every case. It is recognized that each case is different, and those individuals involved in providing health care are expected to use their judgment in determining what is in the best interests of the patient based on the circumstances existing at the time. It is impossible to anticipate all possible situations that may exist and to prepare a pathway for each. Accordingly, these pathways should guide care with the understanding that departures from them may be required at times.