Transcript Cardiovascular Surgery

Cardiovascular Surgery
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Coronary Artery Bypass Graft Surgery
Valvular Surgery
Aortic Aneurysms
Kim Uddo RN MSN CCRN
CABG Indications
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PTCA Failed
Unstable Angina unresponsive to meds
3 vessels
LAD > 75% stenosis
Failed thrombolysis
Ej fx < 35%
Valve disease / vent. aneurysm
Diagnostic Studies
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Cardiac Catheterization
Echocardiogram
Stress test
CXR
12-lead ECG
Blood: coags, CBC, CMP, Enzymes
Conduits
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Saphenous Vein Graft (SVG)
Internal Mammary Artery (IMA)
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LIMA
RIMA
Right Gastroepiploic
Radial
Saphenous Vein Grafts
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Easy to harvest from legs - lots of vessel
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Laproscopically vs surgically
Turn valve direction
10% occlusion in first weeks
Lasts 5 – 10 years
Must take ASA
Leg swelling
LIMA or RIMA
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85 – 95 % Patency at 10 years
Remains attached at origin
Artery can vasodilate
Difficult and timely to mobilize for
anastamosis
More post op pain
Right Gastroepiploic Artery
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Branch of gastroduodenal artery
Laporotomy
Abdominal wound
Timely and most difficult to harvest
Pulled up to the pericardial cavity
Origin intact and connected past blockage
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RCA and Post. descending
Radial Artery
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Artery dilates
MUST have good ulnar flow
Vasospasms (control with meds)
Forearm swelling
Stabilize Pre-op Condition
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Control dysrhythmias
Treat CHF
Relieve Angina
Maintain cardiac output
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CO=HR X SV (preload, afterload, contractility)
Drugs
Intra Aortic Balloon Pump (IABP)
Intra-Aortic Balloon Pump
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Provides Counterpulsation
Balloon inserted in aorta via fem. Art.
Inflates during diastole (AV valves open)
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Timed at dicrotic notch (aortic valve closes)
Increase perfusion forward to brain and ca’s and
backward to kidney
Deflates during systole (SL valves open)
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Decreases afterload when heart ejects blood thus
decreases workload
IABP Indications Pre and Post Op
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Recurrent / Unstable Angina
Cardiogenic Shock from AMI
High risk patient
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Elderly, low Ej Fx, diabetic, MI
LV Failure after surgery
Unable to ween from heart lung bypass
machine after surgery
IABP Complications
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Peripheral Ischemia
Aortic Dissection
Pseudoaneurysm at insertion site
Balloon Perforation
Bleeding and Infection
Peripheral Ischemia
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From emboli formation or the balloon
Hourly assessment of distal pulses,
extrimity color, temp, and capillary refill
Hourly documentation of assessment
May need doppler
Keep leg straight and log roll
HOB < 30 degrees
Balloon Perforation
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Gas leak alarm on pump console
Blood visible in IABP tubing
Turn off pump and call MD stat
Clots will form on nonmoving balloon
IABP Caused Bleeding
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Thrombocytopenia from constant pumping
(platelets are destroyed)
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Monitor platelets and CBC
Movement at insertion site (fem art)
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Monitor site at least hourly & document
Log roll
Pre op CABG Interventions
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Phisohex shower
Shave
Medications
IV antibiotics
Centeral Line / Pulmonary Artery Catheter
CABG: The Operation Sequence
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Patient to OR holding area
Central line or PA Catheter (Swan)
insertion
Harvest saph vein
Median sternotomy
Dissect vessels off of LIMA to mobilize
Heparinize - bolus
CABG continued
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Establish Cardioplegia
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Cold potassium aortic root injection regime
Heart is motionless and bloodless
Cross clamp the aorta
Insert Cardiopulmonary Bypass (CPB) Catheter
into Sup & Inf Vena Cava (directs venous return
to pump oxygenator) and an aortic catheter
(blood is returned to the body)
Establish extracorporeal circulation
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Diverts blood flow from heart and lungs
ABIOMEDS
BVS System 5000
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Decreased Cardiac Output related to alterations in preload
Decreased Cardiac Output related to alterations in afterload
Decreased Cardiac Output related to alterations in
contractility
Decreased Cardiac Output related to alterations in heart
rate or rhythm
Activity Intolerance related to cardiopulmonary dysfunction
Ineffective Cardiopulmonary Tissue Perfusion related to
acute myocardial ischemia
Risk for Infection: invasive procedures
Disturbed Sleep Pattern related to circadian
desynchronization
Disturbed Body Image related to functional dependence on
life-sustaining technology
CABG : Hypothermia
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Establish hypothermia: irrigate topical iced
saline slush across pericardial sac
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This decreases ischemia to heart and organs (28 –
36 degrees C) by reducing tissue requirements 50%
OR is cold and chest is open to cold air
Hypothermia induced Vasoconstriction
Will warm blood prior to ending CPB but pt temp
drops once off the pump & can show HTN and
shivering for first two hours post op
May need Nipride until warm
Induced Hypothermia
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Shivering leads to increased heart
workload
This increased CO2 and L. acid prod.
Chemoreceptors respond
Vasoconstriction occurs
Use warm blankets to reduce shivering .
Take care not to overwarm – vasodilationKeep MAP > 60
CABG: Hemodilution
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Blood diluted with isotonic crystalloid
solution that is used to prime the bypass
machine.
Lowers the colloidal oncotic pressure
Stress promotes ADH production
Come to ICU post op with facial and hand
swelling. Can be ahead by liters of
fluid.Check OR I&O.
CABG: Anticoagulation
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Establish anticoagulation
Heparin bolus
Prevents coagulation in the bypass
machine once blood comes in contact with
the machine’s surface
Stress promotes clotting
CABG continued
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Perform graft anastamosis from aorta to
past the obstructed coronary artery.
Place chest tubes in mediastinal cavity
above and below the heart. Can place in
the pericardial sac.
Place CT in intrapleural space if violated
Loosely stitch on epicardial pacing
electrodes to atrial and ventricular wall.
CABG: continued
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Jump start the heart: shock
Disconnect from CPB
Use IABP if difficulty coming off CPB
Pull out pacing electrode wires through the
chest before closing sternum with wires.
Skin stapled or sutured
Transport to ICU
CPB: Results / Complications
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Hemodilution (interstitial / pulm edema) third
spacing edema and wt gain due to  plasma
protein conc &  capillary permeability.
Platelets damages & vasoactives subs released
in blood (capillary permeability).
Alteration in fluid & electrolyte balance
Alteration in cardiac function (dysrhythmias and
cardioplegia causes ischemia, acidosis,
necrosis, and decreased cardiac output)
CPB cont
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Coagulopathies (bleeding) damaged plts,
heparin, hypothermia induced  clotting factors
in liver.
Catecholamine / renin release (HTN – watch out
for bleeds at suture sites)
Supressed insulin release & epi stimulated
glycogenolysis (hyperglycemia)
Alteration in central nervous system (cerebral
ischemia, plaque, or embolic events)
CPB cont
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Blood sitting in pulmonary capillaries and
mesentary for length of time on CPB so capillary
walls break down ( pulmonary edema,
atelectasis, bowel ischemia, microemboli).
Impaired gas exchange from  surfactant prod.
Increased renin, angiotensin, aldosterone, and
ADH ( sodium & water retention, potassium
excretion)
Serum dilution (Low K, Na, Cl, Mag)
Hemolysis ( RBC’s damaged in CPB )
CPB cont
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Hypothermia (increased SVR, decrease in
contractility & HR & CO thus decreased
perfusion pressure thus decreased urine
output)
Hypothermia causes impaired release of
insulin and low perfusion pressure, lytes
are diluted so altered glucose transport
(hyperglycemia)
Off Pump Normothermic Trend
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Minimally invasive approach/ thoracotomy
Less complications (no CPB)
Higher technician difficulty suturing on
beating heart
Poor visualization
Some aspects of heart unreachable
ICU : Equipment
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Turn on ECG, vent settings, 12 lead, CXR
2 wall suctions (NG, ET)
Brackets on IV poles, thermometer, doppler
Multiple infusion pumps
Autotransfusion set up with CPD
External pacmaker generator with battery
60cc cath tip syringe
Admit into ICU
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Hook to vent
Hook to ECG, NIBP, Pulse Ox,
transducers
Assess ET for placement (may dislodge)
Connect pacer wires to generator
Zero and calibrate pressure lines (Radial,
CVP, Pulmonary Artery)
Admit continued
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Connect CT to autotransfusion
Tape CT connections and check for clots
Empty urometer every hour
Record admit vitals and hemodynamics
HOB 30 degrees
Stat labs and ABG’s CMP, CBC, Plts,
PT/PTT, Enzymes, Troponin
Admit continued
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12 lead ECG and CXR
Hang necessary hemodynamic drugs and
do calculations
Connect NG to suction
Suction ETT
Soft wrist restraints
Monitor and Record
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Vital signs every 15 min for first 4 hours
Then every 30 min for 4 hours
Then hourly
Monitor CT drainage every 15 min for first
few hours then every hour
Breath sounds, peripheral pulses,
hemodynamics and neuro checks every
hour X 4, then every 4 hrs.
Hemodynamics
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Intraarterial Line -usually radial (BP /MAP)
Central Venous Pressure (CVP)
Pulmonary Artery Catheter with balloon
forward flow (Swan-Ganz Catheter)
All have waveforms and pressure readings
(numerical values). Need pressure tubing,
transducer, flush system, & monitor
Arterial Pressure
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Keep patient normotensive!
Low BP / MAP
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Can cause graft closure. Keep MAP > 60.
HR will increase to maintain CO, this increases
oxygen demands on the heart .
High BP / MAP
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Can cause bleeding at graft sites due to increased
pressure.
Increases afterload so L heart works harder.
CVP
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Preload to the Right side of the Heart
Pressure created by volume in the RIGHT side
of the heart. When the tricuspid valve is open,
the CVP reflects RVEDP – right ventricular end
diastolic pressure. Guides fluid volume replacmt.
Not good indicator of L side of heart since the
pressure must go through the lungs (by the time
CVP gets high readings the L side : full failure).
Normal value: 2 – 6 mm Hg
Low CVP
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Hypovolemia / insufficient blood volume
HR will increase to maintain CO.
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CVP falls before MAP
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Increases myocardial oxygen demand
Peripheral vasoconstriction keeps MAP up
CVP excellent warning for bleeding,
vasodilation, diuretics, & rewarming after
cardiac surgery
CVP High
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Fluid Overload
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Heart must increase contractility to move the
larger volume of blood
This increases cardiac workload
Also increases cardiac oxygen consumption
Follow CVP TRENDS to manage volume
replacement or diuretic use
Pulmonary Artery Catheter
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Similar to TLC but longer / has a balloon.
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Flow directional catheter/ 4-5 ports.
Advance to R Atrium (RAP : 4-6)
Inflate Balloon 1 1/2 cc air into balloon port.
Advance to RV (20-30S)
Advance to PA ( PAS: 20-30/ PAD: 8-15)
Advance to wedge position into a small
pulmonary vessel (PCWP: 6-12). Deflate within
10 seconds. Floats back to PA.
PCWP: Preload to the L Heart
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While balloon is inflated, only pressures
on the Left side of the heart are seen.
Diastole: Mitral valve is open
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No valves obstructing between cath tip and
left ventricle.
Pressure exerted by the volume in the LV is
reflected back to the pulmonary capillaries.
“Preload” (L heart) = LVEDP = PCWP
PCWP Low
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Volume Loss (bleeding or third spacing)
Tachydysrhythmias (afib)
Increased intrathoracic pressure (vent)
Increased intracardiac pressures (cardiac
tamponade)
Give volume replacement (autotransfusion
best) or control dysrhythmias or tx
problem.
PCWP High
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Volume Overload.
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Venous Constriction.
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Hypothermia.
Left Ventricular Failure (The Pump).
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Excessive fluid administration.
Acute Myocaridal Infarction.
Give: Tridil drip (this decreases preload and
afterload due to dilation and v. pooling).Or can
try Nipride drip or diuretics.
Afterload
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Pressure the ventricle has to generate to
overcome the resistance to ejection by the
arteries. Systemic Vascular Resistance.
SVR = 900 – 1200 dynes ( L heart )
PVR = pulmonary vascular resistance (R)
Low= hyperthermia or shock
High= hypothermia or shock/constriction
Afterload Drugs
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Elevated afterload give:
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Dilators: Nipride (Nitroprusside), Tridil
(Nitroglycerine), Calcium Blockers, IAPB
Lowered afterload give:
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Pressors: Dopamine, Epinepherine, Norepi,
Neo-Synephrine
Decreased Contractility
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Excessive preload or afterload.
Drugs (negative inotropes).
Myocardial Damage.
Ionic Environment Changes (acidosis ,
electrolyte disturbance, hypoxia).
Give Positive Inotropes:
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Dobutamine, Dopamine, Digoxin
Elevated Contractility
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Drugs (positive inotropes)
Hyperthyroidism
Give:
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Beta Blockers
Calcium Channel Blockers
Reduce inotrope therapy
Thermodilution Cardiac Output
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10cc saline injected in RA port at end of
expiration
Fluid passes temperature sensor
(thermistor) to catheter tip.
Thermistor is already connected to
monitor. Measures core temp change.
Obtain 3 readings and average
Normal CO = 4 – 7 liters/ minute
Cardiac Index
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Individualized Cardiac Output.
CO divided by Body Surface Area
Normal Cardiac Index: 2.5 – 4 liters/ min.
Cardiogenic Shock: < 1.5 liters/min
PA Catheter Risks
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Air Emboli. Pneumothorax. Hemothorax.
Arterial Puncture. PA Art Rupture.
Balloon Rupture. Pulmonary Infarction.
Clots. Emboli. Thrombosis.
Exsanguination. Bleeding.
Infection.
Hypothermia
CABG Post Op Problems
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Low CO Syndrome
Cardiac Tamponade
Dysrhythmias (lethal)
Pulmonary Emboli (3rd Day Post Op)
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Esp if saphenous vein used
MI
Bleeding / Coagulopathies
HTN
Post op problems continued
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Fever
Endocarditis
Organ/ peripheral emboli
Organ Failure (lungs, neuro, renal)
Paralytic Ilieus
Pain/ Pychosis
Electrolyte Disturbance
Low Cardiac Output Syndrome
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Blood Loss
Vascular Dilation
LV impaired
Low Contractility
High Afterload
Hypothermia induced
hypertension
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Active Bleeding at
anastamosis
Intraoperative MI
Increased preload
Decreased preload
Hypovolemia
Decreased CO Secondary to:
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Decreased contractility
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Increased Afterload (hypothermia)
Increased Preload
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CHF, volume excess
Decreased Preload
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from hypothermia and cardioplegia
AMI
Bleed, permeability, hypovolemia
Dysrhythmias (afib common: no atrial kick)
Decreased CO: Bradycardia
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Connect epicardial pacing wires to
external generator if not already
connected.
Turn on generator or increase rate of
pacemaker.
Atropine only used if no pacer wires or
pacer malfunction
Usually need HR of 80 beats/ minute
Cardiac Tamponade
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Clots forming in
mediastinal tubes
Decreased SBP,narrow
pulse pressure
Sudden decrease in CT
drainage
Quiet heart sounds
Low amplitude ECG
Pulsus paradox >10
Wide mediastinum
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Call MD stat
Break up clot in CT or
aspirate clot
MD insert new CT
Pericardiocentesis at
bedside
Rush back to OR to
reopen the chest
Other Diagnoses
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Altered Safety: High
risk for Bleeding
Safety: Risk for
Dysrhythmias/MI
Intravascular fluid
deficit due to third
spacing from CPB,
post op diuresis or
bleeding, rewarming
dilation.
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Decreased gas
exchange sec to low
CO, hypothermia,
altered breathing,
decreased surfactant
production from CPB.
Potential for altered
LOC (emboli)
Stress from Surgery
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Activates ADH
Hold onto water to
keep from going into
shock
Cells swell and third
spacing occurs from
CPB
Edema noted
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IV Fluid Post Op:
D5 ½ Normal Saline
Hypertonic
Pulls water from
swollen cells into the
intravascular space
Increases iv volume
Increases urine
output
Progression
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Extubated by next morning, hopefully
sooner and up in chair. Lung exercises.
1 –2 nights in ICU if no complications.
D/C PA and art lines, CT’s, pacer wires.
Transfer to telemetry.
Cardiac Rehab inpatient.
Cardiac Rehab outpaitent.
Pre-Op Teaching
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No Smoking
Lung exercises : IS
CTDB
ICU Visit
Sensory Preparation
ETT and restraints
Ankle Rotation
Cardiac Rehab
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ICU Routines
Visiting Schedules
Assure Pain
Measures Done
Pain Scale Used
Post op expectations
Explain surgery
TED Hose (2 pair)
Post Op Teaching
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Low Na, Low
cholesterol diet
Medications
Gradual increase in
activities
Stair climb / walk: get
up to 60 min a day,
climb 2 flts before sex
Shower is ok
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No tub baths
No heavy lifting>10lbs
No driving X 6wks:
may be a passenger
No smoking
No fatty diet
Support groups
available & rehab
Valvular Surgery
Diagnosis
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Echocardiogram.
Cardiac
catheterization
detects pressure
changes across a
faulty valve.
ECG show
hypertrophy.
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CXR show
calcification on valves
and increased heart
size
Transesophageal
Echocardiogram
(TEE) and Doppler
Study show color flow
imaging of faulty
valve
Three Methods of Valve REPAIR
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Mitral commisurotomy
Valvuloplasty
Annuloplasty
Mitral Commisurotomy
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To correct mitral stenosis
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Open Method
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Incise fused leaflets, debride calcium
deposits, suture torn leaflets to increase
mobility of valve.
Used in USA on CPB
Closed Method
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Used in Third World Countries off pump
Valvuloplasty
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Percutaneous Transleuminal Balloon
Valvuloplasty (PTBV) (valvotomy)
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Developed after PTCA, balloon inserted in valve and
inflated, works well on MV, only short tem effect on AV
– stabelize for surgery.
Inflations separate fused commisures, cracked
calcified leaflets, stretches valve structures.
Open Surgical Repair
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Suture torn leaflets, papillary muscle, cordae
tendenae
Annuloplasty
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Annulus
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Anatomical ring in which the valve sits.
Surgical Repair
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Good for Mitral Regurgitation
Suture a prostetic ring to the dilated annulus
to increase leaflet coaption or reconstruct
annulus without a ring
Valve Replacement
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Most Common
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Article: When to go to Surgery?
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AVR for stenosis or regurgitation
MVR for stenosis or regurgitation
Before LV dysfunctions or Ej Fx < 55% or
Symptomatic even with good Ej Fx
True open heart surgery
Pre Op Care
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Try to give 48 hours of antibiotics
Begin on Nipride drip to decrease preload
and afterload
Emergency AVR due to acute endocarditis
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Body hasn’t compensated yet = emergency
Give antibiotics on call to OR
Valves Used for Replacement
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Biological: Tissue Valves
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Porcine (pig)
Bovine (calf)
Homograft (human cadaver)
Mechanical: Metal and Dacron
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Caged ball
Tilting disc
Bi-Leaflet: mechanical central flow disc/ most
Young Recipients
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If a patient is young, they will probably
receive a mechanical valve since they last
much longer.
If conditions exist that prevent taking
coumadin such as pregnancy, they will
receive a biological valve.
Biological Valves
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Chance of Rejection
Virchow’s Triad activated
Less Durable (lasts 7 years)
Tendency to calcify
Endocarditis: early and late (p 60 days)
Low thrombogenicity (less emboli)
Only 12 wks of anticoagulants if no a fib
Mechanical Valves
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High chance of clot formation
Long term anticoagulation therapy
Mechanical malfunction
Hemolytic anemia
Early and late endocarditis
Virchow’s triad
Last longer (20 years)
Virchow’s Triad
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1. Stasis of Blood Flow (pooling)
2. Tissue Damage
3. Hypercoagulability
Valves are foreign. Susceptable to fibrin
and platlet aggregation. Suture material
and endothelial damage agrivate this.
Give Heparin post op
Post Op Anticoagulation
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Heparin 80u/ kg bolus
18u/kg/hour gtt
Follow PTT or aPTT every 6 hours
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Activated partial thromboplastin time
Therapeutic range : 46- 70 seconds
Get blood thin quickly and keep thin,
subtherapeutic PTT allow clots to form
and are dislodged when thin again.
Discharge Teaching
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Anticoagulation tx
(INR 2.5 – 3.5)
Prophylactic
antibiotics
Incision care
Exercise
Avoid fatigue
endocarditis
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Call MD: S&S of
infection, CHF,
bleeding, planned
invasive or dental
procedures.
Monitor I&O, weight,
and temp.
Diet
Meds
Aneurysms
Definition



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An outpouching or sac (dilitation) of the
arterial wall commonly occuring in the
aorta at the weak spot.
½ of all aneurysms >6cm rupture in 1 yr
Dangerous
Thrombi like to deposit here
3 layers of Arterial Wall
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Adventitia : outer layer
Media : middle layer
Intima : inner layer
Segments of the Aorta
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Ascending thoracic aorta
Aortic arch which includes the decending
thoracic aorta
Abdominal aorta
Terminal aorta
Four types of Aneurysms
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Fusiform (true)
Sacculated (true)
Dissecting
Pseudoaneurysm (false)
True aneurysm

Has at least one vessel layer intact
Fusiform

Circumferencial and uniform in shape
Saccular

Pouch like buldge connecting to one side
of the aneurysm. Narrow neck.
Pseudoaneurysm


Disruption of all 3 layers of arterial wall
resulting in a leak of blood that is
contained in surrounding sutures.
Examples:


Post PTCA femoral insertion site
D/C of the IABP
Causes

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Athlerosclerosis : plaques and fibrin
deposits weaken wall, loose elasticity
Infection
Congenital disorders
Trauma
HTN, men
Smoking
How Discovered

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By Accident :ruling out something else
Routine physical
CXR
US
ECG
Aortagraph done when surgery
contemplated
Diagnostic Tests

Ultra sound

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CT scan

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accuratley detects cross section size
Abdominal aortography


gen location & size
exact position
ECG
MRI
Thoracic Aneurysms
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
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Asymptomatic usually
Deep difuse chest pain
Hoarseness (laryngeal nerve pressure)
Dysphasia (esophageal pressure)
Distended neck veins (SVC pressure)
Dyspnea, cough, airway obstruction
Abdominal Aneurysms
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
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Pulsitile mass : periumbilical
Audible bruits over aneurysm
Asymptomatic or
Back, flank, abd pain (lumbar pressure)
Epigastric discomfort (bowel compression)
Bloody stools, post prandial pain
Blue toe syndrome: plaque breaks off
Repair criterion
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Aneurysm > 6.0 cm (text says 6.5).
If it is 2 times > normal artery diameter.
Not repaired if small or poor surgical risk.
Traditional Surgery vs.
Endovascular Graft Surgery
Traditional Surgery:
Aneurysmectomy


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Midline incision xyphoid to pubis
Cross clamp aorta above and below site.
Heparinize first. If clamp above renals,
check for acute tubular necrosis :ATN.
Incize diseased aorta.
Insert synthetic graft
Suture native aortic wall around graft.
Endovascular graft surgery
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Percutaneous approach
Femoral arteries in each leg
Synthetic graft deployed anchored c hooks
Graft inside vessel prevents bowel erosion
Less pain & blood loss (500cc vs 1-3
liters), no scar, fast to heal
Extubated in OR, to PACU, then to floor
on telemetry vs ICU overnight.
Pre-op care
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Fix carotid or coronary arteries first
Get baseline vitals & mark pulses
Abdominal girth
Assess all systems
Teaching
Titrate Nipride or Tridil to Keep MAP 60-90
Most serious pre-op complication

Rupture, Bleeding , Shock
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
High HR, Low BP, LOC, urine output, clammy
May have Turner’s Sign

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Severe back pain, flank eccymosis
A clot could dislodge
Post op goals
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Normal tissue perfusion
Intact neurological / motor function
Prevent post op complications
Tissue perfusion
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Titrate Nipride or Tridil to keep MAP 60-90
May use lasix
Keep systolic 95-160, warm if hypothermic
Give fluids, blood, & meds to keep
adequate BP to keep graft open
Prevent low BP to keep graft patent.
Palpate pulses q 15 X4, q1hr x 4, q4 hrs.
MEDICATION SHEET FOR CONTINUOUS INFUSION
Drug:________________________________________
tual Drug in Solution: ___________mg in __________cc of ____________
_____________________________________________________________
Current Infusion Rate:_________________cc/hour
ne. Mcg/kg/min___? Mcg/min___? Mg/min___? cc/hr___? Mcg/hour___?
Patient Weight:__________________________kg
lculate the current infusion dose being delivered at the current rate. Show ca
tting the pump: cc’s per hour = ( mcg/kg/min ordered ) x (kg) x (60 minut
(concentration of solution in mcg pe
Calculating the dose being infused based on set rate on the infusion pump
Mcg/kg/min = (set pump rate cc/hr)x (concentration mcg/cc)
(kg body weight) x ( 60 minutes)
Your calculation:
Continuous Medication Sheet



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
Nipride 50mg in 250cc D5W
50mg:250cc=xmg:1cc
250x=50
X=50/250
x= o.2mg per cc or 200mcg per cc
This is the concentration of the solution.
Book says begin at 0.3 mcg/kg/min
Computation of Nipride

ml’s per hour=

(0.3mcg)(100kg)(60min/hr)
__________________________________
(200 mcg/cc concentration)

1800/200= 9cc hour

(Patient Weight is 100kg)

Now the Pump : 300 ml’s/hr

Mcg/kg/min =

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
(300ml/hr)(200mcg/ml concentration)
_____________________________
(100kg body weight)(60 min/hr)
= 10mcg/kg/min
Text says not to exceed this dose
Tissue Perfusion: Renal



Complications of surgery: hypotension,
dehydration, prolonged cross clamped
aorta, blood loss.
Nursing: Mointor : BUN,Creat, CBC, Na,
Osmolality,I&O, signs of shock, back pain,
& pulsating mass in abdomen.
Nursing: Give: Autotransfusion, fluids,
heparin to decrease clots.
Tissue Perfusion: Bleeding



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Observe for falling trend in CVP (earlier
sign then BP)
Monitor labs: coagulation studies, CBC
Hourly: CVP, PA Pressures, vitals
Every 4 hours: H&H, abdominal girth
Tissue Perfusion: Mesentary



Paralytic ileus common. Intestines
become swollen and bruised from
manipulation.
Observe for: absent bowel sounds and
passing of flatus, distended abdomen,
N&V.
Encourage early ambulation. Connect NG
to low cont. suction & irrigate for patency.
Tissue Perfusion: Fluids/ Lytes

Monitor: daily weights, I&O, wound & NG
drainage, abnormal labs.

Give: autotransfusion, blood transfusion –
PRBC’S, colloids, intravascular fluids.
Tissue Perfusion: Cerebral


Neuro checks hourly X 4, then every 4
hours.
Motor checks hourly X 4, then every 4
hours.
Other Post Op Complications

Impaired resp function from vent and abdominal
pain.

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NGT to decr. gastric distention and aspiration
Dysrhythmias from hypothermia, hypoxia, lytes
disturbed.
Infection: Wound and invasive lines
HTN: graft bleed
Hypotension: graft collapse
Pain: scale, comfort, possible dissection
Aortic Dissection


Results from a small tear in the intimal
lining of the artery, allowing blood to track
between the intima and the media –
creating a false leumen.
Most Common: thoracic aorta: 90%mort.



Ascending aorta or aortic arch
Longitudinal splitting of medial layer
Each pulse=dissection continues=Emergency
Risks

Cystic medial necrosis



HTN
Marfan’s Syndrome


Destruction of medial layer of elastic fibers
Connective tissue disease
Pregnancy
Symptoms




Sudden pain in back, chest, or abdomen
Ripping or Tearing pain
Dyspnea possibly
Possible murmur

Ascending aortic dissection usually produces
aortic valve insufficiency.
Complications of Dissection


Cardiac Tamponade
Blood escapes form dissection into the
pericardial sac.
Pre Op Management

 BP and contractility to pulsitile force.

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Vasodilators (Nipride) and beta blockers (olol)
ECG r/o MI, echocardiogram, aortography.
CXR may show wide mediastinum.
Manage CHF and Pain.
Blood replacement.
Stat Surgery: ascending aortic dissection.
Descending a.: try meds first if possible.
Post op Care: Synthetic Graft Rpr


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 BP: semifowlers bedrest, quiet, pain
control, antihypertensive meds.
Monitor: ECG, A-line BP, LOC (clots)
Observe for: widening pulse pressureaortic valve insufficiency.
Pulse checks .
CPB and vent complications.
Discharge Teaching






Same as CABG
No lifting of >5lbs for 4-6wks
Sex dysfunction possible due to clamping
of aorta. This  flow to penis.
Observe feet for color, warmth, swelling.
Antihypertensives and neg inotropes.
Antibiotics prior to invasive procedures.
c