Cardio Flashcards
Function of pulmonary artery catheter (3)
detect heart failure or sepsis, monitor therapy, and evaluate the effects of drugs
Indications for Swan-Ganz (8 general)
Management of complicated myocardial infarction
Hypovolemia vs cardiogenic shock
Ventricular septal rupture (VSR) vs acute mitral regurgitation
Severe left ventricular failure
Right ventricular infarction
Unstable angina
Refractory ventricular tachycardia
Assessment of respiratory distress
Cardiogenic vs non-cardiogenic pulmonary edema
Primary vs secondary pulmonary hypertension
Assessment of type of shock
Assessment of therapy
Afterload reduction
Vasopressors
Beta blockers
Intra-aortic balloon counter-pulsation
Assessment of fluid requirement in critically ill patients
Hemorrhage
Sepsis
Acute renal failure aka Acute Kidney Injury
Burns
Management of postoperative open heart surgical patients
Assessment of valvular heart disease
Assessment of cardiac tamponade/constriction
For which patients are you most likely checking K and Mg? (2) How frequently?
For patients at risk for arrythmias (post MI, low EF) and those being actively diuresed, you will likely be checking K and Mg twice daily.
Preferred method of repleting electrolytes? Which is not absorbed well PO?
If the patient has a central line, write “mix for central line”.
If they only have a peripheral, try to give replacement PO, but be cautious on an empty stomach. Magnesium is not absorbed well PO.
Rule to adjust electrolyte need for kidney fnc
The general rule of thumb is to divide the patient’s required electrolyte need by their creatinine (in mg/dL). For creat, 1 mg/dL = 88.4 uM
Example:
Patient’s K is 3.0 and Cr 141 –> 100 mEq*88.4/141 –> give the patient 60 mEq.
For decreased renal function:
Always error on the side of UNDER replacement. Calculate and round downward if indicated. Patients on hemodialysis should rarely require electrolyte repletion as they tend to increase. If dangerously low, be cautious in repletion.
K target for repletion
K (goal ≥ 4.0)
What dose of K gives what rise in plasma K?
Usually 10 mEq will give you a rise of 0.1 mEq/L
Examples:
- 0 – 100mEq
- 8 – 20mEq
K: difference between IV and PO administration
IV and PO have an equivalent effect.
Fastest K infusion times (periph vs central line)
Fastest infusion time is 10 mEq/hr through a peripheral line, or 20 mEq/hr for a central line if on a monitored bed.
Mg target for repletion
Mg (goal ≥ 2.0)
What dose of Mg gives what rise in plasma Mg?
Usually 1 gm for each 0.1 mEq/L.
Examples:
- 6 – 4 gm IV
- 8 – 2gm IV
Mg oral dose?
Magnesium oxide can be used PO (4 tabs being equal to 1 gm) but it is not absorbed well.
Phosphate target for repletion
Phos (goal ≥ 3.0)
Formulations for phosphate replacement (2) and doses
KPhos or NaPhos.
> 2.0 – oral neutraphos 2 tabs po TID x 3 doses
1.5- 2.0 – 0.08 mmol/kg IV over 6 hrs
0-1.5 – 0.16 mmol/kg IV over 6 hrs
If the patient needs K as well, they will get 4.4 mEq of K for every 3 mmol of Kphos.
Phosphate replacement: be careful in the setting of ______
hypercalcemia
Septal territory: Which leads and vessel(s)?
-Septal (V1, V2) - LAD
Anterior territory: Which leads and vessel(s)?
-Anterior (V3, V4) - LAD
Lateral territory: Which leads and vessel(s)?
-Lateral (V5,V6, I, aVL) - left circumflex territory or LAD (diagonal)
Inferior territory: Which leads and vessel(s)?
-Inferior (II, III, aVF) - RCA (85%), Circumflex (15%), or sometimes wrap-around LAD; one hint is to look at lead I. If the ST segment is elevated it suggests circumflex, if the ST segment is depressed it suggests RCA.
Posterior territory: Which leads and vessel(s)?
-Posterior (V1-V3) - high R, ST depression, and tall T waves in V1-V3 suggests infarct and not ischemia. Turn the ECG over and V1-V3 looks like an ST elevation. Will almost always have concurrent inferior infarct (II, III, aVF).
Absolute contraindications to ALL stress testing (6)
acute PE, MI within 48 hours, aortic dissection, uncontrolled BP (usually SBP >180), uncontrolled arrhythmias, uncontrolled CHF.
Options to “stress” (3) and options for evaluating the heart’s response (3)
stress: treadmill, pharmacologic, and vasodilator
response: ECG, echo, nuclear
When to choose exercise stress test over others?
If patient can exercise and functional status is adequate (can walk two blocks without stopping), always choose exercise.
When to choose treadmill (ECG-monitored) exercise stress test versus other monitoring in exercise stress test? (6)
Does ECG show: LBBB, WPW, paced rhythm, on digoxin, major ST/TW changes at baseline, LVH?
- If NO, exercise ECG (treadmill) test.
- If YES, can choose exercise echo or exercise with nuclear imaging. These two have similar sensitivities/specificities, but stress echo is technically more difficult to organize and perform. For this reason nuclear stress tests are most commonly done under these circumstances.
If patient cannot exercise, which stress test to do? (2)
Dobutamine (pharmacologic stress) + echo OR regadenoson (next generation adenosine - vasodilator) + nuclear.
Dobutamine is a positive inotrope with mainly β1 activity used to simulate exercise and increase myocardial workload. Regadenoson (Lexiscan) is a single bolus, selective adenosine receptor agonist (vasodilator stress) which vasodilates the coronary arteries, and must be combined with nuclear imaging.
