Sleep Apnea: Causes, Symptoms, and Treatment

Ideal Body Weight 

Ideal body weight is height (in meters square) times 22, where 22 is the ideal body mass index (BMI), normal BMI ranges from 18·5–25 kg/m 2 ( Bhaskaran et al., 2014 ). 

Signs, Symptoms and Physical Findings 

Severe morning headaches suggests that the patient has uncontrolled hypertension. Loud snoring in the context of his obesity suggests sleep apnea. Cyanosis suggests that his oxygen saturation is very low and his COPD is worsening or not well controlled. Height of 5 ft 11 in and weight of more than 355 lbs gives a BMI above 49kg/m2 suggesting that he is morbidly obese. Distended neck veins suggests that he is developing pulmonary hypertension and there is impaired venous return to the heart. Edema of 4 plus suggests that he is going into congestive cardiac failure and there is poor venous return to the heart causing fluid extravasation from the vascular compartment into interstitial space. 

ABG Findings 

Partially compensated metabolic alkalosis; pH is higher than the normal upper limit (pH 7.45), HCO 3 levels are way higher than upper normal reference range of 26mEq/L, PaCO 2 is elevated above normal (normal upper limit is 45mmHg) in an attempt to correct the alkalosis, full compensation not yet achieved. 

X-Ray Findings 

Lung hyperinflation, prominent pulmonary vasculature, cardiomegaly, and left sided pleural effusion with obliteration of the left costo-phrenic angle. 

Orders Recommended 

Inhalation respiratory therapy using bronchodilators, inhaled corticosteroids and oxygen therapy 

Change in Patients Condition 

The change will be negligible, oxygen saturation is set at a low level below 90% and the FIO2 at 0.25 instead of 1.0 recommended in COPD 

Interpretation of ABG 

Fully compensated respiratory acidosis; the pH is within the normal reference range (pH 7.35-7.45), PaCO 2 is markedly elevated at 81mmHg and the HCO 3 have skyrocketed above the upper limit of 26mEq/L to correct the respiratory acidosis caused by obstructive sleep apnea. 

Changes in Patient’s Therapy 

Mechanical hyperventilation to lower the levels of PaCO 2 with a Ventilator settings: tidal volume of 6ml/kg, RR of 5-8, I/E ratio of 1:4, PEEP of 4, and FIO 2 of 1.0 

Protocols 

Oral appliance therapy (OAs) as an alternative ( Sutherland et al., 2014 ) to continuous positive airway pressure (CPAP)/ bilevel positive airway pressure (BiPAP) or ensuring tolerance to CPAP ( McEvoy et al., 2016 ). Surgical intervention (upper airway (UA) corrective surgery) maybe an option if the obstructive sleep apnea is not controlled on CPAP ( Zaghi et al., 2016 ). Medications like statins to help with weight reduction is recommended ( Chirinos et al., 2014 ). 

References 

Bhaskaran, K., Douglas, I., Forbes, H., dos-Santos-Silva, I., Leon, D. A., & Smeeth, L. (2014). Body-mass index and risk of 22 specific cancers: a population-based cohort study of 5· 24 million UK adults. The Lancet , 384 (9945), 755-765. 

Chirinos, J. A., Gurubhagavatula, I., Teff, K., Rader, D. J., Wadden, T. A., Townsend, R., ... & Chittams, J. (2014). CPAP, weight loss, or both for obstructive sleep apnea. New England Journal of Medicine , 370 (24), 2265-2275. 

McEvoy, R. D., Antic, N. A., Heeley, E., Luo, Y., Ou, Q., Zhang, X., ... & Chen, G. (2016). CPAP for prevention of cardiovascular events in obstructive sleep apnea. New England Journal of Medicine , 375 (10), 919-931. 

Sutherland, K., Vanderveken, O. M., Tsuda, H., Marklund, M., Gagnadoux, F., Kushida, C. A., & Cistulli, P. A. (2014). Oral appliance treatment for obstructive sleep apnea: an update. Journal of Clinical Sleep Medicine , 10 (02), 215-227. 

Zaghi, S., Holty, J. E. C., Certal, V., Abdullatif, J., Guilleminault, C., Powell, N. B., ... & Camacho, M. (2016). Maxillomandibular advancement for treatment of obstructive sleep apnea: a meta-analysis. JAMA Otolaryngology–Head & Neck Surgery , 142 (1), 58-66.