Cardiac Axis Deviation

right way wrong way sign

At some point or another, we have all heard someone mumble the terms “ECG axis”, “cardiac axis” or “cardiac axis deviation” when looking at a 12 lead ECG. But what does axis mean? I’ll let you in on a little secret, but you have to promise to tell EVERYONE! Here goes: cardiac axis is just a fancy way to discuss the flow of electrical conduction within the heart. And the kicker? It’s actually a relatively easy concept to understand.  Continue reading

How to Diagnose ANY Cardiac Rhythm Systematically

ecg heart flatline

Narrow complex tachycardia…hmm, but isn’t that supraventricular tachycardia?

Broad complex tachycardia…VT…no wait, it’s VF…hang on, asystole (oh, oh!)

It’s atrial fibrillation…wait, what about atrial flutter?

Regular, no wait…is that irregular?

Let’s not forget all those different heart blocks…

What happened to a good ol’ run of straight forward sinus rhythm?

With so many cardiac rhythms to remember, wouldn’t it be nice to be able to get to the correct diagnosis each and every time? The beauty about cardiac rhythms are that they are all fairly predictable. If you ask the right questions in a systematic manner, it will get you to diagnosing the right cardiac rhythm pretty much every time! Don’t believe me? Why not give it a shot by using this flowchart I have designed to do just that:

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Understanding How Anticoagulants Work

warfarin anticoagulation stop the clot

As discussed in the article “The Clotting Cascade Made Easy”, a blood clot is formed when activated platelets are trapped in stabilised cross linked fibrin. The process of fibrin formation is controlled by procoagulation factors (factors that promote blood clotting) and anticoagulation factors (factors that inhibit blood clotting). If the ability of the body to maintain this equilibrium is disrupted, we could either bleed to death or become one big blood clot! Continue reading

The Third International Consensus Definitions for Sepsis and Septic Shock

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!

breathing hypoxic drive

We’ve all heard it at some point or another: “Don’t give that COPD patient too much oxygen”. It has led us to believe that oxygen is a REALLY bad thing in patients with chronic obstructive pulmonary disease (COPD). This has caused nurses to be afraid to put oxygen on a COPD patient with low oxygen saturations (SpO2); yes, even in patients with SEVERE hypoxia! Why? Because of a little something known as the hypoxic drive… Continue reading

Removing the Road Blocks: Understanding Heart Blocks

cardiac conduction pathway

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 kidney injury aki

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!

chest xray analysis

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!

ecg dot application hair removal image

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