Question 1

During spontaneous ventilation, the diaphragm and other respiratory muscles create gas flow by raising the pleural, alveolar, and airway pressures.

Accepted Answer

During spontaneous ventilation, the diaphragm and other respiratory muscles create gas flow by lowering the pleural pressure, which in turn lowers alveolar and airway pressures, allowing air to flow into the lungs due to the pressure gradient.

Question 2

Positive pressure ventilation causes an increase in intrathoracic pressure and compression of the pulmonary blood vessels leading to an overall decrease in ventricular output, stroke volume, and pressure readings.

Accepted Answer

Positive pressure ventilation increases intrathoracic pressure, which compresses the pulmonary vessels and the heart, leading to decreased venous return to the heart, reduced ventricular filling, and consequently, a decrease in cardiac output, stroke volume, and arterial blood pressure.

Question 3

Oliguria is defined as urine output < 400 mL in 24 hours (or <160 mL in 8 hours).

Accepted Answer

Oliguria is medically defined as a urine output that is less than 400 mL in 24 hours, which is a key indicator of reduced kidney function or fluid intake issues.

Question 4

The caloric cost of breathing for COPD patients is about 10 times that of normal individuals because of the increased work of breathing necessary to overcome the high airway resistance and V/Q abnormalities.

Accepted Answer

COPD patients experience increased work of breathing due to high airway resistance and ventilation/perfusion (V/Q) abnormalities, significantly raising their caloric expenditure for breathing compared to healthy individuals.

Question 5

Sustained hyperventilation of less than 24 hours causes respiratory alkalosis and increases cerebral blood flow and intracranial pressure.

Accepted Answer

Sustained hyperventilation causes respiratory alkalosis, which actually decreases cerebral blood flow and intracranial pressure due to vasoconstriction.

Question 6

Under normal conditions, the ____ and tidal volume are directly related in positive pressure ventilation.

Accepted Answer

The answer of Under normal conditions, the ____ and tidal...

Question 7

Positive pressure ventilation increases ____ and decreases cardiac output.

Accepted Answer

Positive pressure ventilation increases mean airway pressure (mPaw), which can lead to decreased venous return and subsequently reduced cardiac output.

Question 8

A decreased venous return (or filling of ventricles) leads to a reduction in ____.

Accepted Answer

A decreased venous return reduces the amount of blood filling the ventricles (preload), which directly decreases stroke volume. Since cardiac output is the product of stroke volume and heart rate, a decrease in stroke volume also reduces cardiac output.

Question 9

During mechanical ventilation, ____ is not affected to a great extent because of the capability of the systemic venous circulation to compensate or regulate changing blood pressure and volume.

Accepted Answer

Pulmonary capillary wedge pressure is primarily influenced by left atrial pressure and is not significantly affected by changes in systemic venous circulation during mechanical ventilation.

Question 10

Which of the following is important for eliminating wastes, clearance of certain drugs, and regulating fluid, electrolyte, and acid-base balance?

Accepted Answer

The kidneys play a crucial role in eliminating wastes from the body, clearing certain drugs, and regulating fluid, electrolyte, and acid-base balance. They filter blood, remove waste products, and adjust bodily fluids to maintain homeostasis.

Question 11

Which of the following is a drug that is eliminated by tubular secretion?

Accepted Answer

Furosemide is primarily eliminated by the kidneys through tubular secretion.

Question 12

____ dysfunction may be monitored by measuring the prothrombin time and bilirubin and albumin levels.

Accepted Answer

Liver dysfunction can be monitored by measuring the prothrombin time (which reflects the liver's ability to produce blood clotting factors) and the levels of bilirubin (a waste product processed by the liver) and albumin (a protein made by the liver). These tests help assess the liver's function in processing substances and producing essential proteins.

Question 13

Which of the following is an effect of PEEP and increased intra-abdominal pressure?

Accepted Answer

Increased intra-abdominal pressure decreases functional residual capacity by compressing the lungs.

Question 14

____ is an example of a nonmechanical cause of muscle fatigue that may lead to ventilatory failure.

Accepted Answer

Malnutrition is a nonmechanical cause of muscle fatigue because it leads to a lack of necessary nutrients for muscle function and energy production, potentially resulting in ventilatory failure due to weakened respiratory muscles.

Question 15

Energy requirements for critically ill patients are normally computed by using the Harris-Benedict equation. This equation estimates the resting energy expenditure (REE) based on weight, height, age, and ____.

Accepted Answer

The Harris-Benedict equation estimates the resting energy expenditure (REE) based on weight, height, age, and gender.

Question 16

When TPN is used, it is essential to keep the amount of dextrose, a(n) ____, to a minimum as it can cause lipogenesis and increase O₂ consumption and CO₂ production.

Accepted Answer

Dextrose is a type of carbohydrate. When used in Total Parenteral Nutrition (TPN), excessive amounts can lead to increased fat synthesis (lipogenesis) and higher oxygen consumption and carbon dioxide production in the body.

Question 17

Carbon dioxide acts as a vasodilator in ____ blood vessels.

Accepted Answer

Carbon dioxide acts as a vasodilator in cerebral blood vessels. This means that an increase in CO2 levels in the blood can lead to the dilation of blood vessels in the brain, enhancing blood flow to this vital organ. This mechanism is crucial for maintaining adequate blood flow and oxygen supply to the brain, especially under conditions where CO2 levels might be elevated.

Question 18

Which of the following is a neurologic change associated with hypoxemia?

Accepted Answer

Decreased mental and motor functions are neurologic changes associated with hypoxemia.

Question 19

During positive pressure ventilation, pressures measured in the ____, left atrium, pulmonary artery, and right atrium are slightly higher than those measured during spontaneous ventilation.

Accepted Answer

The answer of During positive pressure ventilation, pressures measured in...

Question 20

Which of the following is a pathophysiologic change associated with short-term (<24 hours) hyperventilation?

Accepted Answer

The answer of Which of the following is a pathophysiologic...

Quiz 2: Effects of Positive Pressure Ventilation