Of course, Scotch is a colloid

In discussing blood pressures, and fluid resuscitation, my current precept asked a simple question, “When would you use crystalloids over colloids, assuming both were available?”.  Further discussion led to a narrowing of the question to, “When would you use crystalloids and pressors, rather than simply switching to colloids?” Since there are a variety of reasons to use any fluid resuscitation, let’s make this a trauma patient.  Mr. Smith was using his chainsaw to remove a fallen tree on his property when – whoops! – chainsaw slips and he has a deep cut on his anterior thigh.  EMS arrives, bleeding is controlled to an oozing wound.  Mr. Smith is ashen, tachycardic and hypotensive.  The nearest ED is a 20-minute response. Now, to understand why the precept posed this question, you need to know that it takes far less of a colloid solution to produce the same effect on blood pressure as lots of crystalloid.  Generally, 250ml of colloid has the same BP effect as 4 liters of crystalloid.  That is, 1/16th the amount of colloids does the work of crystalloids. “What!”  you exclaim.  “DTs, this means that…  hmmm, 4/4 = 1 liter, therefore 250/4 = 62.5… this means that instead of hanging a liter of saline wide open to raise a blood pressure, I can draw up a 50ml syringe of this ‘colloid’ of which you speak and bolus a nice big systolic BP almost immediately!  Why, this revolutionizes EMS!  A ...
Source: DTsEMT - Category: Ambulance Crew Authors: Tags: Learning Curve Source Type: blogs