Transcript Hemodynamic

HEMODYNAMIC MONITORING
NUR 351/352
PROFESSOR DIANE E. WHITE RN MS CCRN PhD (c)
Equipment Needed for Hemodynamic Monitoring
•Transducer: an instrument that senses physiological events &
transforms them into electrical signs
•Amplifier: connects to transducer and an electrical cable;filters out
interference so signal can be displayed
•Monitors: provides display of original signal
•Catheter, tubing flush system (single or double): pressure bag is
500cc Normal Saline with 10cc of 100u/ml of heparin; delivers
continuous cc/hr to keep line open; catheter may be arterial or
venous
Monitoring Hemodynamic Measurements
•Arterial – used for unstable BP or frequent ABG’s or labs
•Controversial regarding accuracy
•Inserted by MD, RT, or Anesthesia
•Inserted into any artery
•Waveform: peak represents SBP and Ventricular contraction,
lowest point reflects peripheral resistance & diacrotic notch is on
the downward stroke & results from aortic valve closure
•MAP – mean arterial pressure represents perfusion pressure in
aorta and branches; SBP-DBP/3 + DBP = MAP
•Nursing considerations
•Central Venous Pressure – represents blood return to the heart;
abnormalities usually secondary to altered venous tone and / or blood
volume
•Inserted by MD under sterile conditions
•Normal value is 0-8 mm Hg
•Increase in blood volume = increase in CVP (vice versa)
•Triple Lumen Catheter (TLC); distal port on TCL and proximal on
Swan Ganz catheter
•Measured at end of expiration: ventilated patients lowest part of
waveform and vice versa for spontaneous breathing
•Pulmonary Artery Catheter or Swan Ganz Catheter – allows monitoring
of Left Ventricular function
•Various ports – proximal (cardiac output), distal (PA), balloon
(wedge or PCWP), RV (pacer port) & temp (core blood temp)
•Inserted by MD under sterile conditions at the brachial, subclavian,
internal jugular or external jugular veins
•All measurements done at end of expiration
What can we monitor with the Swan Ganz Catheter?
•PAP – pulmonary artery pressure; @ 25/10 with average 15
•PCWP – pulmonary catheter wedge pressure; @ 6-12; use of
DPAP if balloon not working
•Cardiac Output – can be measured intermittently or continuously
•-- injectate is D5W or NS @ 10cc
•--errors in CO
•-- 3 values averaged (within 10%) of each other
•-- CO = 4-8 L/min
•-- CI or cardiac index = CO/BSA usually greater than 2
•Mixed Venous Oxygenation (SVO2) – allows clinician to look at
overall picture of O2 used by the body organs
•CVP – central venous pressure 0-8mmHg
•SVR – systemic vascular resistance- measures the opposition to
blood flow exerted by blood vessels; 800-1200 normal value
•Formula: SVR= MAP-CVP x 80/ CO
•PVR – pulmonary vascular resistance
•Formula: PVR= MAP-PCWP x 80/CO
Volume Effects on Hemodynamic Monitoring
•
What is the difference between intracellular and
extracellular volume?
1. Arterial Pressure
2. Central Venous Pressure
3. PAP/PCWP
4. Cardiac Output
5. SVR
Pharmacological Agents Used in Hemodynamic Monitoring
1. Arterial Pressure
•
Dopamine > or= 5 mcg/kg/min up to 20mcg/kg
•
Epinephrine mcg/min
•
Neosenephrine mcg/min
•
Levophed or norepinephrine mcg/min
2. CVP
•
Volume controlled
3. PCWP/PAP –increase CO by decreasing PAP and PCWP
•
Dobutamine 5-20 mcg/kg/min
5. Cardiac Output
•
Dobutamine and Natrecor
•
Must be sure enough volume on board to gain desired effect
6. SVR
•
Nipride mcg/kg/min used to decrease SVR and increase CO
•
Cardene 5-10mg/hr
Inotropic Agent Calculations
 Difference
between positive and negative inotropic
drugs?
 Dosing charts: CONCENTRATION of drug must
match in order to use charts
 Pharmacy directions for drug adminstration:
always DOUBLE-CHECK!
 Fudge Factors: a way of calculating dosages and
rates
Fudge Factors
 Know
the concentration of drug ordered
 Know the patient’s weight in kilograms
 Know the volume of dilution
 Know correct dosage administration for drug
ordered
 Remember constants
Fudge Factor Formula
How is the drug run? mcg/min, mcg/kg/min,
mcg/kg/hour, mg/min
 Fill in the necessary formula components

mg x 1000
volume x kg x 60
mg x 1000
volume x kg
mg x 1000
volume x 60
mg
volume x 60