Advanced | Cardiac Diseases and Anesthesia Flashcards
(38 cards)
A 62-year-old man is undergoing elective coronary artery bypass grafting and aortic valve replacement for three-vessel coronary artery disease and aortic stenosis. Shortly after intubation, heart rate increases from 75 to 100 bpm and blood pressure decreases from 130/70 to 70/40 mmHg with acute, severe ST-segment depression in lead V5. Which of the following is the most appropriate management?
(A) Crystalloid
(B) Ephedrine
(C) Esmolol
(D) Nitroglycerin
(E) Phenylephrine
(E) Phenylephrine
Keyword:
Aortic Stenosis = Phenylephrine
Aortic Insufficiency = Ephedrine
Nitroprusside therapy for hypertension should be discontinued in the presence of:
(A) acute myocardial infarction
(B) increasing metabolic acidosis
(C) methemoglobinemia
(D) mitral regurgitation
(E) renal failure
(B) increasing metabolic acidosis
During protamine administration following separation from cardiopulmonary bypass, blood pressure decreases from 100/70 to 60/30 mmHg and peak inspiratory pressure increases from 26 to 60 cm H2O. The most appropriate next step in management is administration of
(A) diphenhydramine
(B) dopamine
(C) epinephrine
(D) methylprednisolone
(E) terbutaline
(C) epinephrine
Hemodynamic goal in the anesthetic management of coronary artery disease is best described with which of the following:
A. Maintaining afterload
B. Hypotension is better than hypertension
C. Increase in preload
D. Increase contractility
A. Maintaining afterload
Which of the following is the MOST sensitive indicator of left ventricular myocardial ischemia?
A. Wall-motion abnormalities on the echocardiogram
B. ST segment changes in lead V5 of the electrocardiogram (ECG)
C. Appearance of V waves on the pulmonary capillary wedge
pressure tracing
D. Decrease in cardiac output as measured by the thermodilution
technique
A. Wall-motion abnormalities on the echocardiogram
Oxygen consumption (Vo 2 ) is measured in a 70-kg subject on a treadmill at
2500 mL per minute. This corresponds to:
A. 1 metabolic equivalent (MET)
B. 5 METs
C. 10 METs
D. 15 METs
C. 10 METs
(C) One MET is equal to the amount of energy expended during 1 minute at rest, which is roughly 3.5 mL of oxygen per kilogram of body weight per minute (3.5 mL/kg/min).
- For a 70-kg (150 lb) person, one MET would equal 250 mL O2 per minute, so 2500 mL would correspond to 10 METs
(Miller: Basics of Anesthesia, ed 7, p 190)
At less than 1 MAC, which of the following inhalation agent will display the greatest degree of coronary vasodilation?
A. Desflurane
B. Isoflurane
C. Sevoflurane
D. Enflurane
B. Isoflurane
The three main volatile agents used in clinical practice today are
desflurane, isoflurane, and sevoflurane.
- Isoflurane has the greatest degree of coronary vasodilation, however this effect is clinically insignificant in doses less than 1 MAC.
Which of the following is the BEST treatment option to resolve an elevated PCWP(Pulmonary Capillary Wedge Pressure) in the setting of intraoperative ischemia?
A. NTG
B. Phenylephrine
C. Labetalol
D. Furosemide
A. NTG
A patient with Mitral stenosis suddenly presented with atrial fibrillation. In less than 10 minutes, hemodynamic instability occurred with a palpatory BP. At this point, the most appropriate step in the management is:
A. Direct current cardioversion
B. Amiodarone with max dose of 15mg/kg
C. Verapamil 2mg IV
D. Digoxin 500mcg LD
A. Direct current cardioversion
All of the following are valid treatment option in the setting of atrial fibrillation. However, with a patient that is hemodynamically unstable, the primary option is EARLY cardioversion.
A 40 year old patient with mitral stenosis came in for elective hernia surgery. At the ER, the intern called your attention for what seem to be an abnormal ECG finding. The most likely arrythmia in this patient is:
A. Atrial fibrillation
B. Nodal AV block
C. PVC
D. Torsades de pointes
A. Atrial fibrillation
1). The increasing left atrial pressures (LAPs) result in: (i) increased risk of pulmonary hypertension which will leads to compensatory RV hypertrophy, dilation, and then eventual RV failure with associated tricuspid regurgitation (TR), and (ii) increased LAP, LA dilation, and increased risk of atrial arrhythmias (atrial fibrillation is present in about 40% of patients with MS).
Ultimately, there is decreased LV stroke volume due to poor LV filling in diastole.
The medical therapy for MS should aim to slow the heart rate (with β- or calcium channel blockers)
to promote diastolic LV filling.
- If patients with MS develop acute AF, immediate rate control is paramount with pharmacologic measures, followed by synchronized cardioversion if needed.
A 40 year old patient with mitral stenosis came in for elective hernia surgery. Which of the following anesthetic hemodynamic goal should be aimed in the management of this patient?
A. Avoid hypercarbia
B. Decrease preload
C. Decrease RV contractility
D. Permissive hypercapnia
A. Avoid hypercarbia
- Maintain preload in these patients.
AVOID the following:
Hypercarbia
Hypovolemia
Hypoxia
Acidosis
- These conditions can constrict the pulmonary vasculature thus compromising the preload.
Which of the following procedures is hypotension MOST likely expected during cardiac surgery utilizing cardiopulmonary bypass (CPB):
A. Insertion of venous cannula
B. Insertion of aortic cannula
C. Sternal splitting
D. Harvesting of grafts
A. Insertion of venous cannula
- During insertion of the venous cannulas, preload is significantly decreased by physical obstruction. Aortic cannula insertion typically results in far less hemodynamic derangements.
Sternal splitting is an expected time of stimulation with associated hypertension.
Harvesting the grafts is a time of low level stimulation where hypotension can be problematic, but not as predictable as during venous cannula insertion.
Which of the following is accurate in terms of the effect PPV(positive pressure ventilation) on the cardiac hemodynamics?
A. Increased preload only
B. Increased afterload only
C. Increased in both preload and afterload
D. Decreased in both preload and afterload
C. Increased in both preload and afterload
Which of the following hemodynamic goals in a patient with MITRAL REGURGITATION is accurate?
A. Avoid bradycardia
B. Decreased in preload
C. Increased in afterload
D. Maintain low HR
A. Avoid bradycardia
TRUE or FALSE
Spinal anesthesia in the setting of hemodynamically stable mitral regurgitation is an acceptable anesthetic plan.
TRUE
The effect of sympathetic blockade in the afterload may actually improve the regurgitation in MR patients.
Yup, it is OK.
If GA-GETA is planned, avoid drugs that can increase PVR.
Inhaled anesthetic will DECREASE preload so YUP, it is also beneficial.
- Regurgitation = AVOID BRADYCARDIA
- Stenosis = Maintain HR!
TRUE or FALSE
Spinal anesthesia in the setting of hemodynamically stable mitral stenosis is an acceptable anesthetic plan.
FALSE!
Dictum:
Avoid the following in the setting of MS(Mitral Stenosis)
AVOID Hypovolemia
AVOID hypoxia
AVOID Hypercarbia
AVOID Acidosis
Increased PVR = Worsening of RV failure
An 18-month-old child with tetralogy of Fallot is anesthetized with halothane and nitrous oxide. Following intubation, oxygen saturation decreases abruptly from 85% to 45%. The most effective treatment is
(A) discontinuation of halothane
(B) hyperventilation
(C) intravenous epinephrine
(D) intravenous phenylephrine
(E) positive end-expiratory pressure
(D) intravenous phenylephrine
In patients who have undergone cardiopulmonary bypass, administration of milrinone is most likely to result in an increase in which of the following?
(A) Arterial blood pressure
(B) Heart rate
(C) Pulmonary capillary wedge pressure
(D) Stroke volume
(E) Systemic vascular resistance
(D) Stroke volume
- Reduces LV afterload and INCREASES cardiac output.
- less increase in HR than catecholamines
- arterial and venous vasodilation by blocking cGMP metabolism.
A patient has a heart rate of 110 bpm one year after heart transplantation. His tachycardia is most likely the result of:
(A) altered baroreceptor sensitivity
(B) cardiac denervation
(C) compensation for a fixed stroke volume
(D) cyclosporine
(E) prednisone
(B) cardiac denervation
Which of the following statements concerning isolated mitral stenosis is true?
(A) Afterload reduction increases cardiac output
(B) Pulmonary artery occlusion pressure overestimates left ventricular filling pressure
(C) Pulmonary hypertension is irreversible
(D) Tachycardia decreases the mitral transvalvular gradient
(E) Thermodilution cardiac output measurements are unreliable
(B) Pulmonary artery occlusion pressure overestimates left ventricular filling pressure
Which of the following is ACCURATE pertaining to the hemodynamic GOAL in a patient with HOCM(Hypertrophic cardiomyopathy?
A. Sinus bradycardia
B. Increase the contractility
C. Decrease in afterload
D. Maintain preload
D. Maintain preload
An aortic valve area of 1.0 cm2 is considered:
A. Mild aortic stenosis
B. Moderate aortic stenosis
C. Severe aortic stenosis
D. Very severe aortic stenosis
B. Moderate aortic stenosis
Magic number is <1.0 cm2 which is the indicator for SEVERE AORTIC STENOSIS
Mechanical obstruction to LV ejection is one of the key pathologic problem in patients with Aortic stenosis. In early stage of the disease, which of the following is LEAST likely expected to happen?
A. Mitral regurgitation
B. Abnormal stroke volume
C. Normal contractility
D. Atrial fibrillation
B. Abnormal stroke volume
In the early stage, normal stroke volume and normal contractility is still possible.
In AS LV afterload is determined by the stenotic AV, and stroke volume depends upon preload;
- AS is considered a “preload dependent” state. Providing adequate volume to fill
the left atrium is necessary to facilitate diastolic LV filling.
With progressive diastolic dysfunction the probability of atrial fibrillation increases. The
“atrial kick” of sinus rhythm remains critical to preserved LV diastolic filling and cardiac output.
Which of the following patients with aortic stenosis is MOST likely to have the shortest life expectancy if treatment is delayed?
A. Aortic stenosis with symptom of ‘angina’
B. Aortic stenosis with symptom of ‘syncope’
C. Aortic stenosis with symptom of ‘dyspnea’
D. Aortic stenosis with symptom of ‘orthopnea’
C. Aortic stenosis with symptom of ‘dyspnea’
Recent guidelines recommend aggressive treatment of AS.
- Life expectancy, following the development of specific symptoms, is 5 years for angina, 3 years for syncope, and 2 years for dyspnea.
5 years - Angina
3 years - syncope
2 years - dyspnea*
Barash | 9th edit
