…is in. The three phases following a sudden cardiac arrest were described by Weisfeldt and Becker (2002). Drawing on physiology, observational and experimental studies, they…

…because the vibrations in the piezoelectric crystals, and thus the electric current they send back to the machine, vary with the amplitude of the reflected…

…incorporated in modern ECG machines) are to be preferred. QTc duration is calculated automatically in all modern ECG machines. Most machines present the longest QTc…

…is referred to as left axis deviation. The axis is calculated (to the nearest degree) by the ECG machine. The axis can also be approximated…

…is referred to as left axis deviation. The axis is calculated (to the nearest degree) by the ECG machine. The axis can also be approximated…

…metabolic disorders, hypoxemia, antiarrhythmic drugs, or electromagnetic disturbance caused by other machines/devices. Below follows ECG tracings demonstrating each type of failure. Figure 1. Failure…

…by a repolarization (recovery). The action potential occurs in all cardiac cells but its appearance varies depending on cell type. During de and repolarization ions…

…more complicated, indexes that are utilized in modern ECG machines but the sensitivity and specificity are only negligibly better than the old indexes. Figure 2…

…the investigator performs simple measurements and Doppler recordings, which the ultrasound machine uses to calculate various hemodynamic parameters. The Doppler effect The central principle to…

…pulsed wave Doppler sends and analyses sound waves sequentially. The ultrasound machine is programmed to ignore all signals, except those reflected from a certain depth…

…reflected back to the transducer. By analyzing the reflected sound waves, the ultrasound machine creates an image of the tissues. Thus, the principle of ultrasound…

…shift. To analyze reflections from the myocardium, the ultrasound machine filters out all other reflected sound waves, such that only those representing myocardium are recorded…

…incompatible infusions. Haemodialysis, plasmapheresis or other extracorporeal therapy (requires a large bore dialysis catheter, not an ordinary triple lumen catheter). Measurement of central venous pressure…

…or aberrancy. Narrow complex tachycardia where the P waves cannot be discerned on the surface ECG and the RP interval decides between AVNRT, orthodromic AVRT…

…decades but carries several limitations, most notably its reliance on ST segment elevation as the key trigger for emergent reperfusion therapy. This approach fails to…

…indicate turbulent flow; the ultrasound machine is programmed to depict such flows with green color to indicate that the flow is turbulent. Figure 1 displays…

…The Doppler principle, however, remains unchanged: when the sound source and reflectors move towards each other, sound waves are compressed and vice versa . Erythrocytes reflect…

…interval induces ventricular arrhythmias. Figure 1. The QT interval on the ECG. The QT interval is inversely related to heart rate. As the heart rate…

…TGC) . Figure 1. TGC (time gain compensation) and gain control on the ultrasound machine. Gain control: overall gain Gain control regulates the global (overall) gain …

…due to the gel. One or two fingers may be placed gently on the skin to fix the position of the transducer. The ultrasound gel…

…aorta can be regarded as a cylinder, and the same assumption can be made for the other valves. The area is calculated by measuring the…

…have probably noticed that the chest leads (V1 through V6) are displayed on the ECG paper in their anatomically contiguous order from right anterior (V1…

…leads, as the diagnosis can often be established by examining fewer leads. On the other hand, for the purpose of diagnosing morphological changes (e.g…

…Frame rate depends on several factors. The elapsed time for all ultrasound waves to be emitted, reflected and processed in the machine determines the frame…