Supraventricular Tachycardia (SVT)

For the treatment of stable supraventricular tachycardia (SVT) amiodarone is recommended in a dose of 150 mg IV. What differentiates stable from unstabel SVT? Blood pressure for one. If your patient has a systolic blood pressure of less than 80 mmHg that would be considered unstable. Also the presence of chest pain would be another unstable factor. If your patient has unstable SVT, remember the treatment is elctrocardioversion. A common pitfall is that once you have cardioverted your patient people often fail to bolus and start the patient on an anti-arrhythmic drug. What often will happen then is the heart rhythm will then degenerate back to the original arrhythmia.

Beta blockers and hypoglycemia

One of the warnings of beta blockers is something called hypoglycemic unawareness. When a person has a low blood sugar they will exhibit symptoms such as tachycardia, diaphoresis, and restlessness. These symptoms are adrenergic mediated. That means that they are due to increases in the adrenergic hormone epinephrine. Beta blockers block the adrenergic receptor. Therefore, if a patient with diabetes has a low blood sugar the symptoms of hypoglycemia may not appear due to the presence of beta blockers. The danger is that the patient will have a dangerously low blood sugar and will not be aware of the problem due to the absence of symptoms.

Intraosseous lines are just not for kids

It is is tremendous misperception that IO lines are only for kids. IO lines were developed by the military during World War II for use in ADULT combat victims. After the war, the application fell out of favor and was picked up for the use in the resuscitation of infants and children in PALS. If is a skill that easily learned, has good skill retention, and in the scope of practice of many EMTs. I have a full podcast on the topic on the ICU rounds podcast (www.icurounds.com)

Sodium bicarbonate after cardiac arrest?

It used to be taught in versions of ACLS long past, the sodium bicarbonate should be administered as part of ACLS for the treatment of cardiac arrest. This is no longer the practice, but why? The principle academic answer is that there has not been any demonstrable improvement in outcomes. The practical explantation is that in an arrest situation, if an acidosis is present it is most likely from a respiratory cause--- respiratory acidosis. Therefore, the appropriate treatment would be to support the airway and provide mechanical ventilation.

How does acidosis affect pharmacology

Drugs interact wit various tissues through receptors. The interaction of a drug and a receptor are a complex relationship like a lock and key. A lock and key have a complex three dimension structure, and if the structure of either the lock or key change, then they are not capable of interacting.

When a person is in shock they have may have a low blood pH or acidosis. Acidosis causes the structure of the receptors to change shape. When the shape of a lock changes, then a key will not work. This is the problem often with acidosis. When a person has a low plasma pH, some drugs will not be able to bind with receptors and produce the desired physiological response. This is a problem, because if you administer an adrenergic drug like norepinephrine (Levophed) to an acidotic patient you will not see the desired response of an increase in blood pressure.

Norepinephrine (Levophed) is an adreneric agent used to increase blood pressure. It binds with adrenergic receptors.

Negligence

Administration of medications can be dangerous and result in injury to a patient. You need to know the four elements of negligence and what are those definitions. Listen to the latest podcast at www.prehospitalpharmacology.com

Welcome.  This is a blog that will serve as a companion to one of my textbook, "Pharmacology for the Prehospital Professional."   This is a book that is published and will be scheduled for release in February 2009.   

I am of the opinion that pharmacology is a hard topic to learn.   So many names that are hard to remember and so many difficult thing to remember.   I doesn't need to be so hard for the student or experienced paramedic.   I spent a great deal of effort to try to make this topic understandable for everyone.  We have also set up a podcast that is available for download. With the podcast, I provide a 15 minute lecture that is free to download.  This way you can study your pharmacology while driving, exercising, or working in the yard.

With this blog, I hope to connect the students and the author.  This way we can have a really real time discussion regarding topics and questions that you might have regarding prehospital drug therapy.