I met Mr. MK, a 63 year old Malay gentleman, on the 14th of March 2011 in Ward 3. He came in for chest pains characteristic of ischaemic origin. He has no known medical illnesses but smokes daily (a total of 32 pack years). A diagnosis of Acute Coronary Syndrome was made and after relevant investigations, it was revealed that he had experienced an anterolateral Non- ST Elevation Myocardial Infarction.
Along with aspirin, sublingual glyceryl trinitrate (GTN) and oxygen therapy, a stat dose of fondaparinux was givin in the Accident & Emergency Department. His pain was relieved.
In the ward, he was treated with aspirin, simvastatin, isosorbide dinitrate, enalapril and metoprolol with sublingual GTN to use when necessary. Fondaparinux was replaced with clexane on the 2nd day of admission.
He developed no complications during his stay and serial ECG taking showed no further ischaemia. He was discharged on the 4th day of admission, to be reviewed in a month's time. Medications prescribed were aspirin, simvastatin, isosorbide dinitrate, enalapril, metoprolol and sublingual GTN. He was also referred for an echocardiogram.
Queries:
1. Why was fondaparinux replaced with clexane? I have observed that this is done quite regularly in the medical ward. If cost is the reason fondaparinux was replaced with clexane, why begin with fondaparinux initially?
2. Can these two anticoagulants be used interchangeably?
Hellohello... If I'm not mistaken, Fondarinux is an synthetic unfractionated heparin (UFH) as compared to Clexane (Enoxparin) which is a porcine based Low Molecular Weight Heparin.
ReplyDeleteBoth drugs are used in treatment of cases of Unstable angina and NSTEMI's serving as an anti-coagulant. In these diagnosis's several trials have proven that Clexane has a better clinical outcome compared to UFH's in the acute setting and even during percutaneous intervention.
http://content.onlinejacc.org/cgi/content/abstract/41/4_Suppl_S/55S
There is also a significant difference in the incidence of side effects of these two medications. In one trial they compared the use of these two drugs in a patient with DVT as an ant-coagulation therapy. The study concluded that LMWH causes more episode of minor haemmorhages than UFH's. LMWH is also found to be financially more tolerable compared to the UFH's as anticoagulation therapy for Acute coronary syndromes.
http://content.onlinejacc.org/cgi/content/short/35/7/1699
I hope this gave some background information regarding these two drugs, As to why it was replaced in your patient, could be due to cost issues. It could also be due to Clexane being an porcine based drug, they wanted to get consent from the patient prior to administration, thus started with Fondaparinux and after the patient gave consent proceeded to Clexane. Just my two cents...