Dr.
Thank you for answering my previous question about heparin and G.I. bleeding. Youre providing a great service to people out there. I have a follow up question - In Japan and Korea, they seem to be using nafamostat mesylate (a serine protease inhibitor) as an alternative to Heparin for patients prone to bleeding. It doesnt seem to be in use in the western countries. Do you know anything about this option and why it isn`t used outside of Asia? Thanks.
[QUOTE=muraiken;19115]Dr.
Thank you for answering my previous question about heparin and G.I. bleeding. Youre providing a great service to people out there. I have a follow up question - In Japan and Korea, they seem to be using nafamostat mesylate (a serine protease inhibitor) as an alternative to Heparin for patients prone to bleeding. It doesnt seem to be in use in the western countries. Do you know anything about this option and why it isn`t used outside of Asia? Thanks.[/QUOTE]
I think the short answer to nafamostat is that in severe renal insufficiency … and this applies, too, to chronic maintenance dialysis patients with some residual renal function, nafamostat blocks aldosterone and can precitiate problematic hyperkalaemia (a rising potassium) … and this can occur in dialysis as well as in pre-dialysis patients.
The use of nafamostat in Korea and Japan is - to my understanding … and I may be mistaken here - in the extracorporeal circuits of situations such as ECMO (extracorporeal membrane oxygenation … an artificial oxygen delivery machine [like the so-called heart-lung machine]) as it is used in ICUs rather than for maintenance haemodialysis for patients with CKD.
The two clinical situations - acute ICU and chronic outpatient haemodialysis - are really chalk and cheese, and something that works well for one doesn’t always apply well to the other. In ICU, there is commonly CRRT (continuous renal replacement therapy … like haemodiafiltration) running in the background. If so, this would provide an easy control mechanism for side-effects like hyperkalaemia. In contrast, in outpaient chronic dialysis, there may be 2-3 non-dialysis days between treatments when the potassium can (does) rise and any agent that may give additional impetus to a high K+ is risky. Further, in someone ‘given’ to gut bleeding - eg: a watermelon tummy - the risk of potassium release from digesting blood in the intestine might be an additional concern. Finally (see below) there are country-specific regulatory issues. I think these may be the simplest explanations here.
As for international differences in drug and equipment use, patterns of use do vary - sometimes quite markedly - from country to country. For example: some agents that are available to you are not available to us here due to (licencing) restrictions from our(Australian) TGA while we, in Australia, have access to a number of therapeutic agents unavailable to you the US due to your FDA retrictions.
Similar variations in availability (and usage) apply as a result of individual country ‘quirks’, right across and around the world, as individual country FDA-equivalents apply their own regulations. We do not (I am pleased to say) all follow the US FDA decisions.
There are often good reasons (for and against) in these TGA/FDA rulings … and we live within them. I am not sure if nafamostat has been approved/disallowed by the FDA but it may be another factor in the mix.
John Agar