318 Disorders of Ventilation Flashcards
arterial level of carbon dioxide (PaCO2)?
37 and 43 mmHg
PaCO2 formula
nao da para passar, ver no livro
three variables that determine PaCO2?
altered CO2 production, minute ventilation, or dead space fraction
Which regions of the brainstem control spontaneous breathing?
the dorsal respiratory group (DRG) and the ventral respiratory column (VRC)
what is the preBötzinger complex?
is responsible for the generation of various forms of inspiratory activity, and lesioning of the preBötzinger
complex leads to the complete cessation of breathing.
four major categories of hypoventilation?
parenchymal lung and chest wall disease, sleepdisordered breathing, neuromuscular disease, and respiratory drive disorders
1st signs of neuromuscular disease?
extremity weakness or bulbar symptoms
What are the changes in blood gases in chronic hypoventilation?
Elevated plasma bicarbonate in the absence of volume depletion is suggestive of hypoventilation. An arterial
blood gas demonstrating elevated PaCO2 with a normal pH confirms chronic alveolar hypoventilation.
1st line of treatment in hypoventilation syndromes?
Nocturnal noninvasive positivepressure ventilation (NIPPV)
Pharmacologic agents that stimulate respiration
medroxyprogesterone and acetazolamide
What therapy can be used in patients with hypoventilation from high cervical spinal cord lesions or respiratory drive disorders?
Phrenic nerve or diaphragm pacing
Criteria for OHS?
body mass index (BMI) more or equal to 30 kg/m and chronic daytime alveolar hypoventilation,
defined as Pa more or equal to 45 mmHg at sea level in the absence of other known causes of hypercapnia.
% of cases that the sleepdisordered breathing is in the form of OSA?
90%
overall prevalence of OSA syndrome
3–4% in middleaged men and 2% in middleaged women
nr. of people in the states with OHS?
as many as 500,000 individuals with OHS in the United States
