Friday 23 June, 2006

Index: Anticoagulation

Posted in Best Topics, Michael Tam at 18:37 by Michael Tam

Original article by: Michael Tam

Our nemesis…
…the clot

This is an index page linking a series of articles on anticoagulation.

The delicate balance rages within the human body. At any one time, we are simultaneously at risk from both bleeding to death and transforming into one huge blood clot. The fact that we manage to stay alive at all is quite remarkable.

Anticoagulation with a number of different agents and dealing with the subsequent side-effects of our ministrations is neither simple nor done particularly well by many junior medical staff. In particular, warfarin regimens and adjustments of doses are often based more on voodoo and prayer to the warfarin god, than on any basis in evidence.

Hopefully, this series of articles will help bring some light to this murky field. More so than many of my other articles, I’ve tried to reference the evidence base for therapy.

Monday 15 May, 2006

Index: Alternatives to venepuncture

Posted in Best Topics, Michael Tam at 17:46 by Michael Tam

Original article by: Michael Tam

The most skilled phlebotomist of them all

This is an index page linking a series of articles on alternatives to venepuncture.

Blood collection is the bane of every intern. However, there are many tricks that you can utilise and once you become skilled at it, believe it or not, you may find yourself enjoying the challenge of a difficult venepuncture.

Now, just about anyone can stick a needle into a vein and draw back some blood. The question is what you do when you cannot see a single reasonable vein on any accessible limb? This occurs with alarming regularity in hospital, especially with oncology and renal patients who happen to require regular blood tests.

What you need to do is to break the mindset that the only way you can get blood is by sticking a needle into the lumen of a vein. Arguably, this is the best option for the majority of your patients, but chasing a non-existent vein is not a game that you or your patient finds entertaining.

You have options!

I now have a mix of pity and sense of superiority when I see an intern stressed over a very difficult venepuncture. The books talk about complicated ritualistic techniques such as using a sphygmomanometer cuff to cut circulation to the limb for a few minutes and then taking advantage of the vasodilatation on release. My opinion is that this is mostly nonsense. If an experienced hospital phlebotomist (who literally takes dozens of blood tests each day for a living) cannot get venous blood, it is unlikely that you will either (unless you go for veins he or she dare not touch like the femoral vein or external jugular vein).


The following are a collection of methods outside the realms of “normal” blood collecting. They are all pretty safe and effective.

Monday 8 May, 2006

Index: Intravenous fluid therapy

Posted in Best Topics, Michael Tam at 21:45 by Michael Tam

Original article by: Michael Tam

This is an index page linking a series of articles on intravenous fluids.

Intravenous fluid therapy is the most common “prescription” written by a junior doctor. Paradoxically, however, it is a relatively poorly taught subject with most interns (very quickly) learning on the job. It is common to see the practice of simply “copying the last order”.

When I went through medical school, fluid management was taught – but from a physiological point of view and then by a renal physician. The first was enlightening though not easily translated into clinical practice. The second was simply above my level. And thus in clinical practice, I noticed initially in both myself and my peers that we had a reasonable grounding in fluid physiology but when it came to writing fluid orders on the run, they were based more on art than science… “my gut tells me that the next bag needs to run faster”. Sometimes we were right. Other times it did not matter. At times we were very wrong.

The following is a list of articles that give a practical overview on how to order and use intravenous fluids in most common settings.