A Newborn Is Evaluated for Cyanosis Immediately After Birth

question 165

Multiple Choice

A newborn is evaluated for cyanosis immediately after birth.  On examination, oxygen saturation is 70% in all 4 extremities and does not change despite 100% oxygen administration.  The patient's lungs are clear to auscultation, and there are no heart murmurs or gallops.  Peripheral pulses are normal.  A chest radiograph reveals clear lungs and a normal cardiac silhouette but a narrowed mediastinal shadow.  Which of the following is the most likely cause of cyanosis in this patient?

• A)Impaired alveolar-capillary diffusion
• B)Impaired left ventricular contractility
• C)Inability of hemoglobin to bind oxygen
• D)Right-to-left cardiac shunting
• E)Ventilation-perfusion mismatch

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Definitions:

Trade-In Allowance

The credit a buyer receives for a used item when exchanging it towards the purchase of a new item.

Fixed Asset Turnover Ratio

A financial metric that measures how efficiently a company uses its fixed assets to generate sales, calculated as sales divided by the average net fixed assets.

Book Value

The net value of a company's assets found on its balance sheet, and is calculated by subtracting liabilities from the total value of assets.

Trade-In Allowance

The amount credited to a customer for the trade-in of a used item towards the purchase of a new item.