Cheyne-stokes respiration

Cheyne-Stokes respiration (CSR) is a pattern of breathing characterized by a gradual increase in the depth and sometimes speed of breaths followed by a decrease, resulting in a temporary stop in breathing called an apnea. This pattern repeats cyclically. Named after John Cheyne and William Stokes, the two physicians who first described it in the 19th century, Cheyne-Stokes respiration is often associated with severe illness, particularly heart failure, but can also be seen in cases of brain injury or as a normal variant during sleep at high altitude.

Causes

Cheyne-Stokes respiration is primarily observed in patients with congestive heart failure, where it is a marker of poor prognosis. It can also occur in those with stroke, traumatic brain injury, or brain tumors, reflecting its association with central nervous system disturbances. Conditions that lead to a reduced blood carbon dioxide level can also precipitate CSR.

Pathophysiology

The underlying mechanism of Cheyne-Stokes respiration involves fluctuations in the control of breathing. In heart failure, for example, delayed circulation time means that blood takes longer to circulate between the heart and the brain. This delay disrupts the normal feedback loop that regulates breathing, leading to periods of hyperventilation (overbreathing) and hypoventilation (underbreathing). The brain's response to carbon dioxide levels in the blood is also thought to be more sensitive in individuals exhibiting CSR, contributing to the cycle of deep and shallow breathing.

Clinical Presentation

Patients with Cheyne-Stokes respiration exhibit a distinctive pattern of breathing that starts with shallow breaths that gradually increase in depth and frequency before decreasing and leading to a period of apnea. This cycle typically lasts from 30 seconds to 2 minutes. While CSR is often asymptomatic, it can disturb sleep, leading to daytime sleepiness, and in severe cases, it can contribute to cardiovascular instability.

Diagnosis

Diagnosis of Cheyne-Stokes respiration is primarily based on the observation of its characteristic breathing pattern, often during sleep studies in patients with suspected sleep-disordered breathing or heart failure. Polysomnography can be used to confirm the diagnosis by providing a detailed analysis of sleep stages and breathing patterns.

Treatment

Treatment of Cheyne-Stokes respiration focuses on managing the underlying condition. In patients with heart failure, optimizing heart failure management can reduce the severity of CSR. Adaptive servo-ventilation (ASV), a type of non-invasive ventilation, has shown promise in treating CSR in heart failure patients by stabilizing breathing patterns and improving sleep quality. However, treatment must be tailored to the individual, taking into account the underlying cause and the patient's overall health status.

Prognosis

The presence of Cheyne-Stokes respiration in patients with heart failure is associated with a worse prognosis. However, with appropriate management of the underlying condition and specific treatments aimed at stabilizing breathing patterns, symptoms can be managed, and quality of life can be improved.