Question

Please answer these question on this case study

Case study

Your patient, 58-year-old K.Z., has a significant cardiac history. He has long-standing coronary artery disease (CAD) with occasional episodes of heart failure (HF). One year ago, he had an anterior wall myocardial infarction (MI). In addition, he has chronic anemia, hypertension, chronic renal insufficiency, and a recently diagnosed 4-cm suprarenal abdominal aortic aneurysm. Because of his severe CAD, he had to retire from his job as a railroad engineer about 6 months ago. This morning, he is being admitted to your telemetry unit for a same-day cardiac catheterization. As you take his health history, you note that his wife died a year ago (about the same time that he had his MI) and that he does not have any children.

He is a current cigarette smoker with a 50-pack-year smoking history. His vital signs (VS) are 158/94, 88, 20, and 97.2° F (36.2° C). As you talk with him, you realize that he has only minimal understanding of the catheterization procedure.

Several hours later, K.Z. returns from his catheterization. The catheterization report shows 90% occlusion of the proximal left anterior descending (LAD) coronary artery, 90% occlusion of the distal LAD, 70% to 80% occlusion of the distal right coronary artery (RCA), an old apical infarct, and an ejection fraction (EF) of 37%. About an hour after the procedure was finished, you perform a brief physical assessment and note a grade III/VI systolic ejection murmur at the cardiac apex, crackles bilaterally in the lung bases, and trace pitting edema of his feet and ankles. Except for the soft systolic murmur, these findings were not present before the catheterization.

After assessing K.Z., the physician admits him (with a diagnosis of CAD and HF) for CABG surgery. Significant laboratory results drawn at this time are Hct 25.3%, Hgb 8.8 g/dL, BUN 33 mg/dL, and creatinine 3.1 mg/dL. K.Z. is given furosemide (Lasix) and 2 units of packed RBCs (PRBCs).

Five days later, after his condition is stabilized, K.Z. is taken to surgery for a three-vessel coronary artery bypass graft (CABG × 3 V). When he arrives in the surgical intensive care unit (SICU), he has a Swan-Ganz catheter in place for hemodynamic monitoring and is intubated. He is put on a ventilator at FiO2 0.70 and positive end-expiratory pressure (PEEP) at 5 cm H2O . His latest hemoglobin (Hgb) is 10.3 mg/dL. You review his first hemodynamic readings and arterial blood gases.

ABG:

pH = 7.37

PaCO2 = 46 mmHg

PaO2 = 61 mmHg

SaO2 = 85%

6. What is your interpretation of his arterial blood gases on 70% oxygen?

7. what is your evaluation of K.Z's hemodynamic status, base on the results displayed?

8. Do you think the hemodynamic values reported previously reflect poor left ventricular function or fluid overload, and why?

9. K.Z is receiving continues IV infusions of norepinephrine (Levophed) and dobutamine. Why is K.Z receiving these medication.

10. What are your responsibilities when administering norepinephrine and dobutamine to K.Z?

After 3 days in the SICU, K.Z.'s condition is stable, and he is returned to your telemetry floor. Now, 5 days later, he is ready to go home, and you are preparing him for discharge.

11. List at least four general areas related to his CABG surgery in which he should receive instruction before he goes home.

Answer 1

6. He has no sufficient oxygenation, even though he has a normal acid-base balance. He also has low Sao₂ and Pao₂ but it should be elevated on 70% saturation and PEEP. His low Hgb level shows that his blood has a low oxygen-carrying capacity.

7. Low CI  (normal - 2.8-4.2 L/min/mm²)

High PAP (normal - 15- 28 mm Hg systolic / 5-16 mm Hg diastolic)

High PCWP (normal - 6-15 mm Hg)

Increased CVP (normal - 2 -14 mmHg)

It shows that his heart has trouble pumping blood, maybe because of fluid overload. Strict monitoring of his condition is needed.

8. Poor left ventricular function because of low CI and high PAP, PCWP, and CVP.

9. These medications increase the Cardiac Output.