ACUTE FEBRILE ILLNESS

DURING THE COURSE OF ORAL ANTICOAGULATION WARRANTS IMMEDIATE INR CHECK

Abstract

Oral anticoagulation is needed in many patients like after prosthetic valves
insertion, in atrial fibrillation, clots in LA, clots in LV and DVT etc. It is mainly achieved by warfarin
sodium which has many interactions with multiple other drugs and its action varies in different
other chronic diseased states. Objectives: to see the response of acute febrile illness on the
chronic stable state of INR on a fixed dose of oral warfarin sodium. Methods: All the patients
with acutely deranged INR who had a stable and controlled INR previously and a fixed dose
of warfarin sodium were admitted in the cardiac surgical ward at FIC and their history was
explored and recorded. A total of 966 patients were admitted in (CSW) during the period of
April, 2012 to April, 2014 with deranged INR. INR was checked twice or sometimes thrice to
rule out the laboratory error. 504 patients were female & 462 patients were male, 56 patients
had repeated admission for their INR control, most of them were callous regarding taking dose
of warfarin so they were excluded from the study. Result: A total of 631 patients had low INR
due to missed dose of warfarin sodium. Out of them 13 patients got stuck valve for which
emergency redo prosthetic valve replacement was done. 06 patients died in emergency due
to late presentation after the prosthetic valve got stuck. Only 279 patients had high INR on
the previous dose of warfarin sodium, out of them 216 patients had out of range INR. They
were treated by FFP transfusion and holding the Warfarin sodium dose for certain period of
time.76% of the patients give H/o acute febrile states 101-103 with rigor & chills (Malaria, enteric
fever, pharangitis, cellulitis, boils and UTI etc. etc.) since last 3-4 days for which they had got
treatment from some local Gen. practitioners and gave the H/o bleeding gums, general body
malaise, bruising, joint aches & pains. 24% of patients denied any acute febrile illness before
their INR got out of range 2 patients died in emergency due to intra cerebral bleed after INR
got uncontrolled. Conclusions: Any acute febrile illness even of short duration may cause
sudden derangement of previously controlled INR on certain fixed dose of warfarin sodium
which can create a life threatening situation like intra-cerebral bleed, haem-arthrosis, excessive
menstrual blood loss leading to severe anemia. Other less dangerous situation are gum bleed,
bruising, joint aches & pains and general malaise. So, it is always advisable and logical to get
INR check when ever any acute febrile illness even of short duration is encountered to avoid
grave situations.