Review Question - QID 100920

Panic attacks typically lead to hyperventilation which leads to a decrease in blood flow and neurologic symptoms.

Panic attacks lead to hyperventilation through stimulation of the sympathetic nervous system. Hyperventilation is defined as the excessive expulsion of carbon dioxide which leads to hypocapnia. Carbon dioxide is a powerful cerebral vasodilator, and decreases in pCO2 cause cerebral vasoconstriction, decreased cerebral blood flow, reduced cerebral perfusion, and therefore neurologic symptoms.

Ham et al. detail the treatment of panic disorder. Both selective serotonin reuptake inhibitors and tricylic antidepressants are equally effective in the treatment of panic disorder and the choice of treatment should be made based on the patient's preference for side-effect profile. Cognitive behavioral therapy has also been shown to be effective. Benzodiazepines have been shown to be effective as well but not as much as the aforementioned therapies.

Meuret and Ritz detail hyperventilation in panic disorder and asthma. Findings from studies suggest that low carbon dioxide plays an important role in panic disorder and raising CO2 levels by therapeutic capnometry has proven beneficial effects in both asthma and panic disorder. Reversing hyperventilation has recently been found to be important for reducing panic symptoms and improving rates of remission.

Incorrect answers:
Answer 1: Oxygen toxicity is not a side effect of hyperventilation but rather of breathing higher concentrations of oxygen.
Answer 2: Hyperventilation results in a decrease in the arterial CO2.
Answer 4: Hyperventilation is typically accompanied by an increased respiratory rate.
Answer 5: Carotid artery obstruction is not a result of hyperventilation.