A patient has a long history of smoking. He has blood studies done because he is very tired, short of breath, and does not feel well. His blood gases reveal the following findings: pH 7.3, HCO3- 25 mEq/L, PaCO2 48 mmHg. What is the interpretation of these gases?

Select all that apply:

Normal range:

• pH: 7.35-7.45
• PaCO2: 36-44 mmHg
• HCO3-: 22-26 mEq/L

Choice A: Decreased Respirations

Decreased respirations, or a slower breathing rate, are not typically associated with acute stress. In fact, acute stress often leads to an increase in respiratory rate as part of the body’s “fight or flight” response. This response is mediated by the autonomic nervous system, which prepares the body to respond to a perceived threat by increasing heart rate, respiratory rate, and blood pressure.

Choice B: Tachycardia

Tachycardia, or an increased heart rate, is a common indicator of acute stress. When an individual experiences acute stress, the body releases stress hormones such as adrenaline and cortisol. These hormones stimulate the heart to beat faster, providing more oxygen and nutrients to the muscles and brain to prepare for a rapid response to the stressor. Tachycardia is a hallmark of the acute stress response and can be easily measured by checking the pulse.

Choice C: Hair Loss

Hair loss is generally associated with chronic stress rather than acute stress. Chronic stress can lead to conditions such as telogen effluvium, where hair follicles enter a resting phase and hair falls out more easily. However, this process takes time and is not an immediate response to acute stress. Therefore, hair loss is not a reliable indicator of acute stress.

Choice D: Pupil Constriction

Pupil constriction, or miosis, is not typically associated with acute stress. In fact, acute stress usually causes pupil dilation (mydriasis) as part of the “fight or flight” response. Dilated pupils allow more light to enter the eyes, improving vision and awareness of the surroundings. Pupil constriction is more commonly associated with relaxation or the body’s “rest and digest” state, mediated by the parasympathetic nervous system.

Choice A: Beta 2 Agonist Decreases Blood Pressure

Beta 2 agonists primarily cause bronchodilation and vasodilation, which can lead to a decrease in blood pressure. However, this is not their primary function, and they are more commonly associated with the relaxation of smooth muscles in the airways.

Choice B: Beta 1 Agonist Increases Blood Pressure

Beta 1 receptors are primarily located in the heart. Activation of these receptors increases heart rate and contractility, which in turn increases cardiac output and blood pressure. Therefore, beta 1 agonists are known to increase blood pressure.

Choice C: Beta 2 Agonist Reduces Blood Pressure

Similar to choice A, beta 2 agonists can cause vasodilation, which may reduce blood pressure. However, this is not their primary therapeutic use, and they are mainly used for their bronchodilatory effects.

Choice D: Beta 1 Agonist Reduces Blood Pressure

Beta 1 agonists increase heart rate and contractility, leading to an increase in blood pressure. Therefore, this statement is incorrect as beta 1 agonists do not reduce blood pressure.