Lecture 2.1b - Interpreting Wiggers Diagram.pdf

Patient monitor: Arterial lines: ◦Continuous monitoring of blood pressure ◦Access sites: radial, brachial, femoral, tibial arteries (radial and femoral most common due to their easy accessibility) ◦Allows continuous monitoring of: ‣ Blood pressure (real-time readings)...

Patient monitor: Arterial lines: ◦Continuous monitoring of blood pressure ◦Access sites: radial, brachial, femoral, tibial arteries (radial and femoral most common due to their easy accessibility) ◦Allows continuous monitoring of: ‣ Blood pressure (real-time readings) ‣ Pulse rate and rhythm ‣ Effects of dysrhythmia on perfusion ‣ Measurement of cardiac output, SV ‣ Specific wave form morphologies might be diagnostic Central venous lines: ◦Swan-Ganz catheters ◦Access sites: right jugular vein (or left), subclavian vein, femoral vein ◦Allows continuous monitoring of: ‣ Right atrial pressure (and right-sided preload) ‣ Central venous pressure ‣ Infuse fluids of medicines (chemotherapy) ‣ Specific wave form morphologies might be diagnostic Wiggers diagram: ◦QRS complex shows ventricular contraction - atrial repolarisation is masked by the QRS wave. ◦T wave shows ventricular repolarisation.  Wiggers diagram: Atrial systole: Wiggers diagram: Isovolumetric contraction: Mid-to-late ventricular systole: Rapid ejection: Mid-to-late ventricular systole: reduced ejection: Early ventricular diastole/isovolumetric relaxation:  Arterial waveform: ◦Aortic valve closes shut; induces pressure on aortic valve more, causing the dicrotic notch ◦Mean arterial pressure (area under the curve) - 2/3 diastole + 1/3 systole ◦Pulse pressure - difference between systolic and diastolic blood pressure (usually about 40 mmHg) - gives the right amount of perfusion ◦Aortic regurgitation - increase in stroke volume, systolic blood pressure increases and so pulse pressure widens ◦Narrow pulse pressure occurs in heart failure, or stenosis Central venous pressure waveform: ◦A wave - atrial contraction ◦C wave - tricuspid valve closure - creates a backward push into the vena cava ◦X descent - atrial relaxation - pressure decreases ◦V wave - venous filling ◦Y descent - emptying of right atrium