Critical Care in the Cardiac Patient
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Transcript Critical Care in the Cardiac Patient
Critical Care in the Cardiac
Patient
Mark Joseph, MD
Carilion Cardiothoracic Surgery
Objectives
• Identify indications for invasive
hemodynamic monitoring in the critically
ill cardiac patient
• Describe key heart failure risk factors
• Illustrate the rationale for mechanical
circulatory support for the
hemodynamically compromised critical
care patient
What is Critical Care
in the Cardiac
Patient?
The Heart
• Center of the being
• Directly and Indirectly Controls the input
and output of every organ in the body
• Ancient books/scriptures describe the
“heart” as the part of the body that
“controls” the being
• Reports of patient post cardiac
transplant having the same urges as
their donors
• Taking care of a cardiac patient by
default means taking care of every
system that is associated to the heart
• The entire patient
• A happy heart = happy organs (patient)
Challenges in Cardiac Patients
Diastolic
Dysfunction
Coronary
Disease
Immune
Disorders
HOCM
Pulmonary
Hypertension
MI/Injury
Valvular
Disease
Renal Failure
Heart
Failure
Nutrition
Invasive Monitoring
• What types of invasive monitoring
• Who needs it
• Non invasive monitoring
– Does it really exist?
Types of hemodynamic monitoring
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Swan Ganz catheter
Pulse Contour Analysis
Bioimpendance
Applied Fick
Echocardiography
Obituary: pulmonary artery catheter 1970
to 2013
“The birth of the conventional pulmonary artery catheter (fondly nicknamed
PAC) was proudly announced in the New England Journal of Medicine in 1970
by his parents HJ Swan and William Ganz. PAC grew rapidly, reaching
manhood in 1986 where, in the US, he was shown to influence the
management of over 40% of all ICU patients. His reputation, however, was
tarnished in 1996 when reports suggested that he harmed patients. This was
followed by randomized controlled trials demonstrating he was of little use.
Furthermore, reports surfaced suggesting that he was unreliable and
inaccurate. It also became clear that he was poorly understood and
misinterpreted. Pretty soon after that, a posse of rivals (bedside
echocardiography, pulse contour technology) moved into the neighborhood and
claimed they could assess cardiac output more easily, less invasively and no
less reliably. To make matter worse, dynamic assessment of fluid
responsiveness (pulse pressure variation, stroke volume variation and leg
raising) made a mockery of his ‘wedge’ pressure. While a handful of die-hard
followers continued to promote his mission, the last few years of his existence
were spent as a castaway until his death in 2013. His cousin (the continuous
cardiac output PAC) continues to eke a living mostly in cardiac surgery patients
who need central access anyway.”
Reasons for declining use of PAC
Increased risk of mortality (24%) with use of right heart
catheterization using PAC
•
Connors et al. JAMA. 1996 Sep 18;276(11).
Thermodilution data provided may not be accurate
•
Phillips et al. Crit Care Res Pract. 2012
Clinicians didn’t know how to interpret data and large
interobserver variability
•
Ilberti et al. JAMA. 1990 Dec 12;264(22).
ESCAPE trial
•
JAMA, October 5, 2005—Vol 294, No. 13
• Movement across all ICUs away from
invasive monitoring
• “Not helpful so we shouldn’t use it”
• Alternatives
• Unfortunately most ICUs/clinicians have
taken a “minimalist” approach
Swan Ganz Catheter
• PAC
– “Gold standard”
– operator dependent
– Tricuspid/mitral valve insufficiency, shunt or
misplacement may influence reliable cardiac
output assessment
– Some overcome by CCO PAC
Minimally invasive
• Pulse contour analysis,
– Calibrated
– uncalibrated
• pulsed Doppler technology,
• applied Fick principle,
• bioimpedance/bioreactance.
Minimally Invasive
• Pulse contour
– based on the principle that SV can be
continuously estimated by analyzing the arterial
pressure waveform.
– severe arrhythmias may reduce the accuracy of
cardiac output measurement, and that the use
of an intra-aortic balloon pump precludes
adequate performance of the device.
“Non-invasive” monitoring
• Pulse contour
• Pro/cons
• All “noninvasive” hemodynamic
monitoring devices are compared to
“Gold Standard”
• How good is something when compared
to something not so good?
Applied Fick Principle
• Partial CO2
rebreathing
• Intubation/vented pts.
• Assume CO
unchanged between
normal/rebreathing
states
• Stable pt. with no
pulmonary shunt
Minimally/Non-invasive Monitoring
• Echocardiography
– Non invasive
– Readily available
• Contractility
– TAPSE
• Volume Status
– E/e’
Echocardiography
• Cons
– Not real time
– Studies show unreliability of E/e’ in patients on
inotropic support/exercise/decompensated
HF/ischemia
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Tachycardia
MR or MVR
Annular calcification
MS/AI
Bioimpendence
• Electrical bioimpedance uses electric current
stimulation for identification of thoracic or body
impedance variations induced by cyclic changes in
blood flow caused by the heart beating.
• Cardiac output is continuously estimated using skin
electrodes or electrodes mounted on an
endotracheal tube
• Mathematical algorithms/modeling to measure CO.
• Conflicting results—may be promising based on
modifications.
Integrative Model
What can we use?
• Look at all the variables
• Sv02, urine output, acidosis (lactate)
– If 2 out of 3 are abnormal likely to be issue with
cardiac output
• CO/CI, Filling pressures (PAD, CVP),
SVR/SVRI
• PA pressures, oxygenation
• Echocardiography
Integrative Model
• Physical Exam
– Hypoperfused state
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Cool extremities
Low urine output
Increasing CR
Confusion
Nausea/Vomiting
Peripheral edema
Ascites
SOB
Integrative Model
• Labs
– Increasing BUN/CR ratio
– LFT
– Coagulation abnormalities
– BNP
– Hyponatremia
– Acidosis
Which patients need this type of
monitoring?
• Current guidelines suggest selective use
– Cardiogenic shock
– Acute on chronic heart failure
– Transplant/VAD patients
– Escalating Inotropic support
– Post procedure/MI with heart failure
– At risk for RV/LV failure
Key Factors Heart Failure
• Pulmonary Hypertension
– COPD
– OSA
– Morbid Obesity
• Congenital Cardiac
• Valvular abnormalities
– History of RF
– Endocarditis
• History of heart failure
Advances in Cardiac ICUs
• Improved understanding of blood
utilization
• Use of hypothermia in decreasing
metabolic demand
• Treatment strategies for heart failure
– Rematch Trial
Mechanical Circulatory Support
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Rationale
Indications
Contraindications
Timing
Devices
Rationale
• Based on concept of reversibility
– Minimize collateral damage
– Body/organ can recover minimal to moderate
damage as long as it is allowed to recover and
has reserve
Indications
• Cardiac- post heart TX, cardiac stun,
Cardiac Failure
• Massive PE, reperfusion lung injury
• Severe Sepsis with Shock
• Cardiac arrest
Mechanical Circulatory Support
Heart Failure
Respiratory Failure
Critically ill patient
Failed Maximal Medical or Ventilatory
Strategies
MCS
Types of Mechanical Circulatory Support
IABP
VAD
MCS
ECMO
Artificial
Heart
E xtra
C orporeal
M embrane
O xygenation
E
C
L
S
xtra
orporeal
ife
upport
What is ECMO?
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First from 1971
Oxygenation outside the body
Support heart and/or lung function
Similar to bypass used in the operating
room but can be used for longer periods
of time
How does ECMO Work?
• Artificial pump used to pump blood out of the
body; oxygen is added to the blood and
carbon dioxide is removed before it is
returned to the patient.
• As the patient improves, we may decrease the
work of artificial pump and let their heart and
lungs do more of the work.
• Physiologic goal
– Improve tissue oxygen delivery
– Remove CO2
– Allow normal aerobic metabolism
– Allow heart and/or lung rest
Traditional VA Cutdown Access
Percutaneous
www.nyp.org
www.nyp.org
First Successful Adult ECMO patient,
1971
Contraindications
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No likelihood of organ recovery
Irreversible organ damage
Disseminated malignancy
Severe brain injury
Unwitnessed cardiac arrest
Aortic dissection/aortic regurgitation
VAD (Ventricular Assist Devices)
REMATCH Trial
N Engl J Med. 2001 Nov15;345(20):1435-43.
Outcomes in Advanced Heart Failure Patients With Left
Ventricular Assist Devices for Destination Therapy
Soon J. Park et al. Circ Heart Fail. 2012;5:241-248
Future Devices
Conclusion
• Cardiac patients most challenging ICU
patients
• Selective use of invasive hemodynamic
monitoring should be employed for
patients with identifiable risk factors for
heart failure in a integrative model
• As this patient population grows,
treatment options improving