Hemodynamics Notes
Hemodynamic Monitoring
o Used to evaluate if oxygen supply is meeting oxygen demand
Can use in diagnosis and evaluation of medical conditions and used to evaluate
patient response to treatment
o
circulatory status
o Goal: accurately assess the patient and provide therapies to optimize oxygen delivery
and tissue perfusion
o Modalities
Noninvasive
NIBP
JVD assessment
Urine output
Pulses
Assessment of labs (lactic acid level)
Invasive
Arterial Line (Arterial blood pressure- ABP)
Central Venous Catheter (can be used to monitor CVP)
Pulmonary Artery Catheter (Swan Ganz catheter)
o Important Terms
Preload
Amount of stretch at end diastole- tells us about the volume in the
heart
Increased preload=fluid overload (treat with vasodilators, diuretics)
Decreased preload=dehydrated or vasodilated (treat with
volume/fluids, vasopressors)
CVP
Afterload
Resistance that the ventricles must push against with systolic ejection
o Affected by vascular resistance
Increased=HTN, vasoconstriction (treat with afterload reducers: ACE
inhibitors, vasodilators)
Decreased=vasodilation (treat with vasopressors)
Contractility
Inotropy=contractility of the heart
Stroke Volume
Amount of blood in one pump of the heart
Affected by preload, afterload, and contractility
Cardiac output
HR x SV = CO
Amount of blood the heart pumps in 1 minute
Arterial Catheter
o Direct measure of blood pressure from catheter placed in artery
o
o
Common sites are radial or femoral artery
Nursing management
Frequent assessment of the site
Neurovascular assessment
o Assess for pain, pulses, pallor, paralysis, paresthesia
o Assess for bleeding
Monitor pressures
SBP, DBP
MAP= mean arterial pressure (70-100)
o Tells us how well vital organs are being perfused
Monitor waveform
Zeroing the system
Done to negate the influence of external pressures such as atmospheric
pressure (ensures that only pressures measured are coming from the
arterial system)
Leveling the transducer
Phlebostatic Axis
Minimize complications
Bleeding
Thrombosis
Air embolism
Systemic infection
Arterial spasm
Catheter removal
Manual pressure held until hemostasis achieved
Pressure dressing applied after catheter removal
CVP Monitoring
o Central venous catheter (central line)
Tip is placed at the junction of the superior vena cava and right atrium
Connected to a transducer and monitor, the pressure recorded is the RAP (right
atrial pressure) or CVP (central venous pressure)
o CVP
Normal 2-6 mmHg
Estimate blood volume and right heart function
Measurement of preload
Pulmonary Artery Catheter
o PA catheter or Swan-Ganz catheter
Specialized catheter placed into the heart
Measures CVP, CO, PAP, PAWP, Sv02, Blood temp
CVP
o Normal 2-6 mm Hg
o Preload
PAP
o Normal 15-25/8-15 mm Hg
o Pressure in the pulmonary artery
PAWP
o Normal 8-12 mm HG
o Wedge pressure (PAWP or PAOP)=indirect measurement of the
left side of the heart
o Balloon inflates and wedges
Do not inflate balloon for more than 15 seconds
Only perform if ordered by physician
CO
o Normal 4-6 L/min
SVR (Systemic Vascular Resistance)
o Normal 770-1500 dynes/sec/cm5
o Calculated with a specific formula (uses ABP, CO, CVP)
o Resistance the left ventricle must pump against to move blood
through the circulation
o Afterload
Increased=HTN, vasoconstriction (treat with afterload
reducers: ACE inhibitors, vasodilators, fluid restriction)
Decreased=vasodilation (treat with vasopressors, fluid
bolus)
Sv02
o Normal 60-80%
o Mixed venous oxygen saturation (amount of oxygen returning
to the heart)
o High=anethesia, paralysis, hypothermia, sedation
o Low=shock, decreased CO, hyperthermia, seizures, etc
Nursing management
Post placement
o Obtain xray to confirm placement
o Monitor EKG rhythm
If PA catheter is pushed too far in- can occlude
pulmonary artery
If PA catheter is pulled out partially, can irritate the
Level transducer
o Phlebostatic Axis
4th intercostal space, midaxillary
Prevent infection
o CLABSI bundle
Chlorhexidine bath
Tubing change q72-96h
Aseptic treatment of ports
Maintain system
o Keep pressure of flush bag >300mmHg
o
o
Monitor waveforms
Keep balloon tip deflated