The Third International Consensus Definitions for Sepsis and Septic Shock

Sepsis is the most common pathway to death following an infection…and it can be avoided! How? With early recognition and timely intervention! Earlier this year, the Sepsis Definitions Task Force members released the Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). But in order to appreciate the need for a new definition, we must first understand the issues with the old definition.  Continue reading

The Hypoxic Drive Theory…DEBUNKED!

We’ve all heard it at some point or another: “Don’t give that COAD patient too much oxygen”. It has led us to believe that oxygen is a REALLY bad thing in patients with chronic obstructive airways disease (COAD). This has caused nurses to be afraid to put oxygen on a COAD patient with low oxygen saturations; yes, even with the REALLY low oxygen saturations! Why? Because of a little something known as the hypoxic drive… Continue reading

Removing the Road Blocks: Understanding Heart Blocks

Ever wondered about the differences between a first, second and third degree atrioventricular (AV) heart block? And not to mention that second degree AV blocks can be further differentiated into type 1 or type 2? You know, because it wasn’t confusing enough as it was! This article is going to explain it all to you! But before we start making heart blocks something that is easy to understand, we should start with a bit of normal electrophysiology through the heart. After all, we can’t understand what is abnormal until we truly understand what is normal! Continue reading

CVVHDF What?! Renal Replacement Therapy Simplified…

Acute renal failure (ARF) is a new onset of the partial or complete reduction of normal kidney function which is characterised by the inability to remove excess water and metabolic wastes from the body. Continuous Renal Replacement Therapy (CRRT) is often indicated in ARF as well as some other conditions, with the decision to commence CRRT on a patient based on the following:  Continue reading

Chest X-Ray Interpretation in 7 Easy Steps!

It is important to understand that when a chest x-ray is taken, light is absorbed according to the density of what it passes. We have different densities within our bodies ranging from bone, to tissue, to fluid, to air. This results in a monochrome display ranging between white to black. There are three distinct things you should look for on a chest x-ray and they all rhyme: Continue reading

ST What?! Recognising Myocardial Ischaemic ECG Changes!

Acute Coronary Syndrome (ACS) does not refer to an adorable coronary artery too cute for it’s own good; it refers to a group of conditions that result in decreased coronary blood flow to the myocardial tissue. With a decreased coronary blood flow, there is a decreased supply of oxygen to the myocardial tissue. And nothing is as bad to the myocardial tissue than a lack of oxygen! If you are the superstitious type, you will believe that all bad things come in threes. No truer words have ever been spoken, with the 3 issues that result from a lack of oxygen to the myocardial tissue all starting with a capital “I”…
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Demystifying the 12 Lead ECG!

Whether you work within a coronary care unit or a general surgical unit, we have all performed a 12 lead electrocardiogram (ECG) on one of our patients at some point or another. We’ve prepped the chest of a patient that could rival some of the sheep shearing competitions that occur in New Zealand. We’ve tried untangling the mess of leads while secretly imagining the face of the colleague that left the ECG machine in such disarray on the dart board of our local bar. We’ve all had to deal with that ONE patient who cannot comprehend what it means to “lie still and quietly”. And after all of that effort to get that perfect print out of an ECG, wouldn’t it be nice to understand what those 12 leads are actually telling you?  Continue reading

Massive Blood Transfusions and Making the Blood Clot!

Blood Transfusion Negative

Ouch! I’ve just given myself a paper cut!

*Utters a string of expletives that would make a pirate blush*

As I apply pressure to my haemorrhaging war wound, I notice that the bleeding slows down to a stop. That is because my body is able to clot at the site of this small injury according to the physiology of the clotting cascade. However, it would be a different situation if I was in a horror movie and had my arm chewed off by zombies! I would now be experiencing a massive loss of blood that would result in the need for a massive blood transfusion. The internal processes of the body to clot may not be sufficient in the setting of a massive haemorrhage, and so it will need the help of some friends in the form of other blood products to help stop the bleeding.

*Cue the Rocky theme song as I battle through a horde of zombies with one arm to find an abandoned hospital, with a fully functional blood fridge, to initiate a massive blood transfusion protocol* Continue reading

The Clotting Cascade Made Easy!

At some point or another, there is a strong probability that we have all seen that dreaded flow chart. You know, the one with all the roman numerals that looks like it was created with the sole intent of confusing us. The one that we try to memorise but secretly hope that no one ever asks us about it. Do you know the one I’m talking about? That’s right; the dreaded coagulation or clotting cascade! And this article is going to simplify it to a point that you not only get it, but remember it as well! Continue reading

Oxygen Flow Rate and FiO2: Understand the Relationship!

Oxygen, we all need it! We do not need a lot of it under normal circumstances, with 21% being the fraction of inspired oxygen (FiO2) of room air. FiO2 is defined as the percentage or concentration of oxygen that a person inhales.  The air that we inhale on a day to day basis is made up of 21% of oxygen, 78% of nitrogen and 1% of trace elements such as argon, carbon dioxide, neon, helium and methane.

Sometimes, 21% of oxygen may not be enough to maintain adequate oxygen saturations. Continue reading