Obstructive Sleep Apnea Flashcards
Pulmonary hypertension benchmark
Pulmonary arterial pressure is higher than 20 mmHg at rest (normal is 10-14 mmHg)
Symptoms of Obstructive sleep apnea
Shortness of breath
- most common
Chest pains
Palpitations
RHF signs
Syncope with exertion
Malaise
Cough/hemoptysis
Voice hoarseness due to impingement of the recurrent laryngeal nerve from pulmonary artery (super rare)
Signs:
- S2 split w/ S3/4 heart sound
- tricuspid regurgitation murmur
- JVD
- hepatomegaly w/ elevated liver enzymes
- Ascites
- similar to COPD on flow volume loops
What benchmark of DLCO is required to start really thinking about pulmonary hypertension?
< 40% DLCO
Pathophysiology of PH
Causes are not completely understood
- thought to be possible narrowing of pulmonary arteries leading to increase pulmonary resistance
Important to diagnosis ASAP since untreated/diagnosed PH = cor pulmonale
- poor prognosis at this point; 5yr survival = 30%
remember to think massive PE as diagnosis If acute rapid PH is present and signs of cor pulmonale occur
Classes of pulmonary artery hypertension
Group 1: idiopathic (this is PAH) - 85% is familial genetics with 75% of the 85% is due to loss of BMPR2 receptors Other causes in group 1 * drugs * connective tissue disorders * autoimmune infections (especially HIV) * portal HTN * left-right congenital shunting
Group 2: LHF (PH)
- MOST COMMON CLASS OF PH
- diagnosed with symptoms of LHF and ECG showing sings of RBBB, CHF and LVH
- current data suggests OSA is here
Group 3: hypoxic vasoconstriction (PH)
- WHO says THIS IS WHERE OSA IS LOCATED
- COPD and altitude changes also occur here
- this is also the group where cor pulmonale is most likely to occur
Group 4: chronic microemboli (PH)
- VQ mismatches with VQ scan usually diagnosises this
- perfusion portion = left side
- ventilation portion = right side
Group 5: everything else (PH)
- most common are
- hemolytic anemia
- systemic diseases such as sarcoidosis
- metabolic disorders
- all other congenital heart diseases other than left-right shunting
Definition of sleep apnea
Recurrent nocturnal cessation of breathing for at least 10 seconds
Lab finds of OSA
- neck circumference > 17 inches = OSA
- elevation RBCs and hematocrit w/ normal WBCs and platelets
- ABG shows low O2 and possibly high CO2 (not always though)
Sequelae of OSA
2nd polycythemia
Systemic HTN
Cardiac arrhythmias
Sudden death
Two types of sleep apnea
Obstructive (OSA)
- excessive parapharyngeal tissue
- being obese
- adenotonsillar hypertrophy
- chronic hypoxia/ hypercapneic
Central
- toxins
- trauma
- infections
- stroke/ bleeding
- advanced Heart failure
Treatment for obstructive sleep apnea
1st is always lifestyle choices
- lose weight and change diet
- modify sleeping position
- avoid alcohol and sedatives
2nd is BiPAPor CPAP
- BiPAP = use if pneumonia/HF or central causes are present w/ minimal CO2 retention
- CPAP = use if retaining CO2
Alternative treatments (is 1st and 2nd dont work)
- surgery
- oral appliances
Treatment of PAH/PH
must determine primary cause 1st and treat that