A note about pre-requisite learning: A clear understanding of human acid-base physiology is necessary before you begin this learning activity An introduction to acid-base imbalances will facilitate your understanding of the contents within this tutorial. Upon completion of this learning activity, you will be able to orecognize clinical manifestations associated with acid-base imbalances. omatch pH values with acid-base imbalances. oselect the correct answer following the review of each case study. ocompare and contrast the step-wise assessment of determining the acid-base balance of the blood. oidentify the appropriate etiology of metabolic acidosis/alkalosis and respiratory acidosis/alkalosis. odifferentiate between compensatory and non-compensatory ABG changes. Sometimes reading and deciphering Arterial Blood Gases (ABGs) can be a challenge! I have provided an interactive online tutorial for your review. Arterial blood gas values reflect ventilation and acid-base balance. The results include the arterial blood pH (concentration of hydrogen ions in the blood) , partial pressure of carbon dioxide (PaCO2) dissolved in the arterial plasma, and the concentration of sodium bicarbonate (HCO3-) in the blood. Our bodies regulate an acid-base balance through a "buffer system." This buffer system neutralizes acids. There are three buffer systems that exist for the maintenance of our acid-base equilibrium: a buffer system … Continue reading →

In 2003 there was a cardiac arrest on a patient 4 hours post cardiac surgery. Over the following four hours his chest was re-opened three times and eventually the patient was re-grafted in his ICU bed on bypass. Many of the nursing and junior medical staff reported they felt disorganised and of little help to the situation and would have performed much better if they had a defined and well practised role. In response to this we created the Cardiac Surgery Advanced Life Support Course. We have devised a set of protocols that address the patient suffering a cardiac arrest and all common serious complications in ICU or on the ward. Our aim was to create a common language for all cardiothoracic practitioners. This protocol has grown and has been accepted as the European Association of Cardiothoracic Surgery's official protocol and has been accepted by the European Resuscitation Council.The Society of Thoracic Surgery also created an expert consensus statement which is published in the Annals of Thoracic surgery (Feb 2017) which sets these protocols as the standard of care in the USA. We hope this course will empower all practitioners to act with confidence to better treat our critically ill … Continue reading →

Ventricular and Atrial Hypertrophy Ventricular hypertrophy is an increase in the size and mass of the involved ventricle. This can be a normal response to cardiovascular conditioning as occurs in athletes and enables the heart to pump more effectively. This type of hypertrophy is physiological, not abnormal, and is reversible. In contrast, other forms of hypertrophy are caused by the ventricle adapting to increased stress, such as chronically increased volume load (preload) or increased pressure load (afterload). This hypertrophy is an adaptation to the stress; however, prolonged stress-induced hypertrophy can lead the ventricular failure. Hypertrophy can also result from disease of the heart (valve disease, cardiomyopathies), genetic abnormalities (e.g., hypertrophic cardiomyopathy), and as a consequence of coronary artery disease. In the case of chronic pressure overload as occurs with chronic hypertension or aortic valve stenosis, the ventricular chamber radius may not change; however, the wall thickness greatly increases as new sarcomeres are added in-parallel to existing sarcomeres. This is termed concentric hypertrophy. This type of ventricle is capable of generating greater forces and higher pressures, while the increased wall thickness maintains normal wall stress. This type of ventricle becomes "stiff" (i.e., compliance is reduced), which can impair filling and lead … Continue reading →