Question

R.B. is a 65-year-old female who presented to the emergency department (ED) via ambulance for acute shortness of breath. Her daughter called an ambulance after finding her mother with an increased respiratory rate and shortness of breath. Upon arrival to the ED, R.B.’s respirations were 40 and shallow with wheezing in the lower lobes and rhonchi in the upper lobes bilaterally. She had positive jugular vein distention and a heart rate of 128. After treatment with albuterol nebulizer via mask, her vital signs were temperature 96.8˚ F, pulse 98, respirations 18, blood pressure 148/84, and O₂ saturation 94% with 15 LPM via mask. Arterial blood gasses showed her pH 7.19, pCO₂ 90, PO₂ 92%, HCO₃ 38. R.B. was intubated for hypercapnia. After an echocardiogram showed an ejection fraction less than 50%, she had an emergency left heart catheterization done with two stent placements into the left anterior descending artery. A pulmonary artery catheter was placed and the initial hemodynamic readings show elevated left ventricular preload. R.B. is now being transferred to the ICU.

5.   You obtain a set of hemodynamic monitoring values. Interpret these results.

Heart Rate	110	Blood Pressure	142/58
Cardiac Output (CO)	4.06 L/min	Pulmonary Artery	52/32 mm Hg
Central Venous Pressure (CVP)	10 mmHg	Systemic Vascular Resistance (SVR)	1499 dynes/sec/cm-5
Pulmonary Artery Wedge Pressure (PAWP)	16 mmHg	Pulmonary Vascular Resistance (SVR)	549 dynes/sec/cm-5
Cardiac Index (CI)	2.25 L/min/m2	Mixed Venous Oxygen Saturation	SvO2 62%

6. Describe each of R.B.'s ventilator settings and the rationale for the selection of each.

7. How does PEEP lower cardiac output?

    

8. R.B. is started on intravenous dobutamine and sodium nitroprusside. How will these medications affect her hemodynamic status?

Answer 1

1,

The ventilator setting for patient shows that heart rate set into higher than 100 to avoid the clopse iccurs due to sudden decrease in the heart rate.

Cardiac output and cardiac index limited to minimum to reduce the working load of heart.

Administration oxygen is to maintain the normal oxygen saturation and also to remove excess carbon dioxide from the body.

7,

PEEP increases the pressure inside the thoracic cage where the heart is situated. Due to this the venous return decreases and this will affect the preload, afterload and ventricular compliance. So the cardiac output decreases.

8,

Dobutamine produced a dose-dependent increase in left ventricular performance, primarily by increasing heart rate, because stroke volume index decreased dobutamine dose. So this will help to decrease the cardiac index. Sodium nitroprusside increases the systemic and pulmonary blood pressure and this will help in maintaining cardiac out put.