Link to the by Nick Mark MD onepagericu.com ARTERIAL LINE ONE most current @nickmmark UTILITY PULSE PRESSURE VARIATION (PPV) version → Arterial lines permit continuous invasive blood Pulse pressure is proportional to stroke volume. Pulse CARDIAC ARREST pressure measurement, frequent arterial blood Pressure Variation (PPV) represents an interaction During cardiac arrest, an arterial line can be used to gauge sampling, and analysis of the waveform can be between lungs and heart. Ventilation (either spontaneous adequacy of CPR (e.g. DBP > 25mmg on waveform), to used to estimate cardiac output, predict volume or mechanical) alters the intrathoracic pressure and identify ROSC, and to differentiate PEA from pseudo-PEA. responsiveness, and identify specific pathologies. causes stroke volume to vary. Greater variability in stoke See Cardiac Arrest OnePager for more. Systolic BP volume (increased PPV) may suggest fluid responsiveness. Dicrotic PRINCIPLE Low PPV High PPV notch A continuous column of fluid between indwelling Diastolic BP catheter and a pressure Arterial MAP calculated pressure transduce allows arterial Systole Diastole from the AUC pressure measurement. Airway For patients on pressors, SQUARE WAVE TEST pressure femoral MAP may be The arterial line can measure BP inaccurately �����"����� IV fluid in PPV = slightly higher than radial unless properly calibrated. Rapidly flushing the pressure bag ������ MAP measurements. line (by pulling the release on the flush device) Specifically, a PPV > 12% is suggestive that there will be an at 300 mmHg generates a square wave. Counting oscillations increase in stroke volume with fluid challenge. However in after the square wave indicates if the arterial line order to interpret PPV 3 conditions must be met: Pressure is working properly. 1. Sinus rhythm (consistent filling time) transducer Normal = accurate BP 2. Mechanically ventilated w/o spontaneous respirations; Flush 1.5 - 2 oscillations TV= 8 cc/kg (consistent effect of ventilator) device 3. Must not have an open chest (heart/lungs interacting) ‘Zero’ defined by the phlebostatic th In contrast to an increase in BP with respiration causing high axis (mid-axillary line at the 4 IC PPV, pulsus pardoxus is the decrease in SBP > 10 mmHg with approximating the aortic root) Square wave respiration, associated with tamponade & other conditions. OVERdamped = falsely LOW BP Absence SPECIFIC ARTERIAL WAVEFORM PATTERNS <1.5 oscillations of dicrotic notch Pulsus alternans - alternating strong and weak pulses; Arterial Fix: Remove extra tubing & any air bubbles. seen in low cardiac output shock states catheter UNDERdamped = falsely HIGH BP Additional Closed blood Sampling >2 oscillations artifactual sampling port spikes Pulsus bisfirens - double Pulsus tardus - late peaking system peaked pulse in severe AR ± AS pulse; seen in severe AS Closed blood sampling systems enable blood draws 14) with minimal waste. They are associated with lower - CARDIAC OUTPUT ESTIMATION 09 Several techniques can be used to estimate cardiac output risk of bacterial contamination and when combined - using an algorithm to analyze the waveform. There are two with smaller size sample tubes and decreased lab Fix: Adjust filter settings on monitor types: uncalibrated and calibrated. None is proven superior. frequency they can reduce blood transfusions. v1.0 (2020 v1.0.