Download 081013.HEMODYNAMICS

HEMODYNAMICS
Carol Peyton Bryant,
RN, MSN, ACNP, CCRN
Priority Care, St. Mary’s
Objectives:
• The participant will be able to discuss
hemodynamic definitons
(cvp,pa,pcwp,co,ci,svr and pvr) and how
they relate to the respiratory patient.
• The participant will use critical thinking
skills in assessing changes in respiratory
status/ventilation with changes in
hemodynamic status.
• INDICATIONS FOR HEMODYNAMIC
MONITORING
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Shock
Pulmonary edema of uncertain etiology
Postcardiac surgery
Cardiac tamponade
Acute respiratory failure
Need to evaluate for fluid status/guideline for fluid
resuscitation
– Need to evaluate hemodynamic response to potent
pharmacologic agents
– MI
• especially with an acute right or left ventricular failure
• Refractory pain
• Significant hypotension or hypertension
Blood pressure
• Blood pressure=CO X SVR
– Changes in blood pressure are caused by either a
change in cardiac output or by systemic vascular
resistance
– MAP
Mean arterial pressure=
SBP + (DBP x 2) = 70-105 mm Hg
3
– The average blood pressure occurring in the aorta
and its major branches during the cardiac cycle
Stroke volume: CO ÷ HR
The amount of blood ejected by the left
ventricle during systole. N= 60-120 ml/beat
Stroke Index: SV ÷ BSA
The SV indexed for differences in body size
by dividing by BSA. N= 30-65 ml/m2/beat
Ejection Fraction:
% of blood in the ventricle that is ejected
during systole. Normally, greater than 50%.
Right Atrial Pressure-RAP
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Normal Value 2-8 mm Hg
Clinical Significance: Equivalent to central venous pressure.
Abnormalities:
Increased
– Right ventricular failure, tricuspid valve abnormalities (stenosis or
regurgitation), cardiac tamponade, right ventricular infarct, VSD with
a left to right shunt.
– Pulmonary stenosis, Postive Pressure ventilation
– Pulmonary Hypertension
• Active: hypoxemic pulmonary vasoconstriction
• Pa02 < 60 mm Hg.
– Pulmonary Embolus
– COPD
– ARDS
• Passive:
– Mitral valve dysfunction either stenosis or regurgitation
Right Atrial Pressure-RAP
• Decreased:
– Hypovolemia
– Anything that vasodilates the body;
• Endogendous systemic vasodilation
– Septic Shock,
– Neurogenic Shock,
– Anaphylactic Shock
• Venous vasodilation
– Nitroglycerin or Morphine
Pulmonary Artery Pressure
PAP or PAS/D
• Systolic: 15-30 mm Hg
• Diastolic: 5-12 mm Hg
• Mean: 10-20 mm Hg
• Clinical Significance: PAP is equal to right
ventricular pressure during systole while the
pulmonary valve is open.
• IF the pulmonary vascular resistance is normal,
the PADP is 1-4 mm Hg greater than PCWP and
can be substituted for it in following the patient’s
hemodynamic measurements.
• Abnormalities:
Increased:
– Hypervolemia, VSD with left to right shunt, Pulmonary
HTN, Positive pressure ventilation, Mitral valve
dysfunction (both), Tamponade,
– Left ventricular failure
Decreased:
– Hypovolemia
– Excessive vasodilation
• If the PADP is 5mm Hg > PCWP, consider acute
respiratory distress syndrome, pulmonary emboli,
or chronic obstructive pulmonary disease.
Pulmonary capillary wedge
pressure PCWP or PAOP
• Normal value 5-12 mm Hg
• Clinical Significance: pcwp is normally
equal to left atrial presure; ~sensitive
indicator of pulmonary congestion or left
sided CHF.
• PCWP is not equal to LVEDP in the
following situations:
• PCWP >LVEDP: Mitral Stenosis, patients
receiving PEEP, Left atrial myxoma,
pulmonary venous obstruction
• PCWP< LVEDP:Stiff ventricle or
Increased LVEDP (>25 mm Hg).
• Abnormalities:
• Increased
– Left ventricular failure with resultant
pulmonary congestions, acute mitral
insufficiency, tamponade, decreased left
ventricular compliance (hypertropy,
infarction).
• Decreased
– Hypovolemia
– Vasodilation
Cardiac Output
CO
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Normal Value 4-8 L/min.
Clinical Significance: CO=SV x heart rate/1000
Abnormalities:
Increased
– Sympathetic nervous system innervation
(endogenous catecholamines ie. stress/exercise)
– Exogenous catecholamines (ie. epinephrine,
dobutrex, dopamine, isuprel)
– Other positive inotropes ie. digitalis
– Infection, early sepsis
– Hyperthyroidism
– Anemia
Cardiac Output-CO
• Decreased
– Cardiac dysrhythmias, decreased contracting
muscle mass (myocardial infarction, ischemia)
mitral insufficiency, VSD.
– Increased SVR (afterload)- systemic or
Pulmonary HTN, Aortic or Pulmonic stenosis
or polycythemia
– Significantly increased or decreased heart
rate.
– Either hyper or hypovolemia
Cardiac Index
CI
• Normal Value: 2.5-4 L/min.
• Clinical Significance: CI= CO/BSA
• Abnormalities:
• Increased: high output failure secondary to fluid
overload, hepatocellular failure, renal disease, septic
shock
• Decreased: hypovolemia, cardiogenic shock,
pulmonary embolism, hypothyroidism, CHF with
failing ventricle.
Systemic Vascular resistance
SVR
• Normal Value 900-1300 dyne/sec/cm-5.
• SVR= (MAP-RAP) x 80 /CO
• Clinical Significance: Resistance against which the
left ventricle must work to eject its stroke volume.
• Abnormalities:
• Increased: hypervolemic vasoconstrictive states
(hypertension, cardiogenic shock, traumatic shock).
• Decreased: septic shock, acute renal failure,
pregnancy.
Remember
• There is a inverse relationship with CI and
SVR.
• If the CI is UP, the SVR will be DOWN.
• If the CI is DOWN, the SVR will be UP.
Pulmonary Vascular Resistance
PVR
• Normal Value: 150-250 dyne/sec/cm-5.
• Clinical Significance: PVR=(mPAP-PCWP) x
80/CO.
• Abnormalities:
• Increased: cor pulmonale, pulmonary embolism,
valvular heart disease, CHF.
• Decreased: hypervolemic states, pregnancy.
Scenario
• 65 year old woman admitted with a fractured hip.
She had surgery 2 weeks ago. Earlier today she
complained about chest pain, shortness of
breath, and a feeling of doom. ABG’s revealed
respiratory alkalosis and hypoxemia. A RRT was
called and she was transferred to ICU, the
physician inserted a PA catheter into her right
subclavian vein. He told the nurse it was placed
so he could better diagnose and evaluate her
thearpy. Her body surface area (BSA) is 1.6 m2.
Parameter
Bp:112/84
MAP: 93 mm
Hg
HR: 110
RAP: 18
PAS/D: 55/32
mPA: 40
PAOP: 6
CO: 4.4
CI: 2.75
↑ ↓ or normal
Why?
Parameter
SaO2: 85%
SV: 40
SVR: 1356
PVR: 618
Svo2: 58%
↑ ↓ or normal
Why?
Dx: ______________ _________________
Considering her history, you would suspect
____________.
You know that means we gotta travel to have
_____________________(test) done.
Goals for this patient
____________________
____________________
____________________