Case presentation - asja

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CASE PRESENTATION
Dr. Amr Marzouk
Assistant lecturer of anesthesia
Faculty of medicine
Ain shams university
• A 68-year-old female, 231 lbs and 5′1″ tall, with a history
of hypertension (HTN), diabetes mellitus, and large joint
chronic
arthritis,
is
scheduled
for
a
laparoscopic
cholecystectomy.
• The patient is non-compliant with her treatment: atenolol
and glyburide.
• On the morning of the surgery, the patient’s blood
pressure (BP) was 145/86 mm Hg, heart rate (HR) 88,
respiratory rate (RR) 20, oxygen saturation 97% on room
air, and temperature 36.8 °C. Her blood glucose was 186
mg/dL.
• Physical examination revealed no abnormalities and the
airway was assessed as a Mallampati class II.
• After
a smooth induction of general anesthesia with
midazolam, fentanyl, propofol, and rocuronium, a #7.0
endotracheal tube was placed atraumatically. Anesthesia
was maintained with mechanical ventilation, isoflurane,
oxygen, air, fentanyl boluses, and rocuronium
• About 30 minutes after the incision, the patient’s HR
increased to 112 beats/minute and her BP became 184/99
mm Hg. The anesthesiologist also noticed a depression of
the ST segment in the monitored V5 cardiac lead.
Questions
 What would you do?
 What treatment would you give?
 Could this event have been prevented?
 Would you extubate this patient?
 What is your plan for the post-operative
care of this patient?
What would you do?
 Risk factors in this patient:
•
•
•
•
68 years old.
Morbid obese (BMI = 45.6) wt: 104kg, height :155cm.
Diabetic.
Hypertensive on atenolol (pulse rate 88 b/min).
 Intraoperative events :
• Blood pressure 184/99.
• Heart rate 112b/min.
• Depression of the ST segment in the monitored V5 cardiac
lead.
(Lead V5 is the most sensitive single lead for intraoperative myocardial
ischemia).
 To be sure of diagnosis:
 Lead II is the best compliment to lead V5 because it




significantly improves the sensitivity for ischemia.
Reliable automated ST segment analysis has arrived and
been incorporated into many monitors.
12 lead ECG
Cardiac enzymes.
TEE.: To see SWMA.
Management
• As
myocardial ischemia can be a
inappropriate anesthetic management so:
manifestation
of
 Evaluate the adequacy of ventilation, oxygenation, and
anesthetic depth.
 Control of hemodynamics.
 Antianginal agents.
 Finally institution of invasive measures such as; intra-
aortic balloon counter-pulsation or angioplasty.
Control of Hemodynamics & Anti-anginal
Agents
Management of Heart Rate Takes Priority.
• Increases in heart rate not only increase myocardial
oxygen demand, but also decrease myocardial oxygen
supply because the duration of diastole is shortened by
increases in heart rate and it is during diastole that
coronary blood flow occurs
Control of Hemodynamics & Anti-anginal Agents
• Heart rate can be controlled by addition of a small dose of
narcotic such as fentanyl but may also require the use of
a β blocker.
• Esmolol is a cardioselective β-adrenergic antagonist. It is
rapidly metabolized in blood and liver by hydrolysis and
has a much shorter duration of action than other available
β blockers
•
Next, IV nitroglycerin Is easily titrated because of its
very rapid onset and short duration of action. It produces
marked venodilation with limited arterial dilation.
•
Thus, left ventricular filling volume and pressure are
usually reduced to a much greater degree than arterial
blood pressure.
•
Obviously, this is of a substantial advantage in
enhancing
effective
coronary
perfusion
pressure.In
addition, nitroglycerin dilates larger coronary arteries and
even the residual lumen within coronary constrictions.
•
Because of these facts, IV nitroglycerin is
usually the first pharmacologic agent chosen for
control of intraoperative myocardial ischemia
after
basic
anesthetic
management
hemodynamics have been optimized.
and
Institution of Invasive Measures
•
If myocardial ischemia still persists or is accompanied
by left ventricular failure, we will request the placement of
an intra-aortic balloon pump, coronary angioplasty, and/or
coronary thrombolysis.
•
An interventional cardiologist will be needed for such
endeavors, but failure to treat persistent myocardial
ischemia or delay in its treatment may result in
unnecessary loss of myocardium, cardiac reserve, or
viable cardiac function
Could this event have been prevented?
• Yes, this event might have been prevented by adequate
preoperative preparation.
ACC/AHA guidelines for the sample case
a. Intermediate risk surgery
b. Minor clinical risk secondary to her uncontrolled
hypertension
These guideline require no further cardiac work-up
unless patient had symptoms of cardiac ischemia (i.e.,
chest pain).
Perioperative Cardiac Risk
Reduction Therapy
What is your plan for the post-operative
care of this patient?
1. Hemodynamically stable
a. Resolution of patient’s ST-depression
b. Extubate
i. Closely monitor the patient and treat any hypertension and
tachycardia.
ii. Be prepared to abort the extubation if the patient develops
ST-changes.
c. Maintain hemodynamics.
d. Send the patient to a cardiac-monitored floor.
e. Cardiology consult
2. Hemodyanmically unstable
a. Keep intubated.
b. Coronary care unit (CCU)
c. Cardiology consult
 ICU admission
•
Factors that may increase the likelihood of postoperative
myocardial ischemia that we can control include tachycardia,
anemia, hypothermia, shivering, hypoxemia, endotracheal
suctioning, and less-than-optimal analgesia.
 Coronary angioplasty:
•
Immediate
coronary
angioplasty
has
been
favorably
compared with thrombolytic therapy in the treatment of acute
MI, but of greater importance is that the risk of bleeding at the
surgical site is believed to be less with direct angioplasty than
with thrombolytic therapy.
•In addition, these reperfusion procedures should not be
performed routinely on an emergency basis in postoperative
patients in whom MI is not related to an acute coronary
occlusion.
•For instance, in cases of increased myocardial demand in a
patient with postoperative tachycardia or hypertension,
lowering the heart rate or blood pressure is likely to be of
greater benefit, and certainly less risk.
MEDICAL TREATMENT:
Therapy with aspirin, a beta blocker, and an ACE
inhibitor, particularly for patients with low ejection
fractions or anterior infarctions, may be beneficial,
whether or not the patients are rapidly taken to the
catheterization
laboratory.
Although
not
intended
specifically for patients who have a postoperative MI,
they are nonetheless appropriate for these high-risk
patients
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