The OHS is characterized by hypersomnolence, hypoxia, polycytemia, headache and edema. Polysomnography is the gold standard diagnostic test. Overnight oximetry with significant oxyhemoglobin desaturation is reasonable to begin treatment. Weight reduction and Non invasive positive pressure ventilation (NIPPV) has evolved as the mainstay of treatment.

 Obesity is a risk factor for deep vein thrombosis (DVT). Heparin and warfarin are the drugs that used for treatment of DVT. HIT typically appears as a 50% or greater reduction in the platelet count after the first exposure to heparin. This case is a obese man with extreme DVT that diagnosed by duplex sonography and symptoms of obesity hypoventilation syndrom.

 In overnight pulseoximetry oxyhemoglobin desaturation was occurred more than 15 times per hours and treatment begins with NIPPV. Patients thrombosis were treated with heparin and warfarin. Heparin induced thrombocytopenia (HIT) and cutaneous necrosis was occurred and drug therapy withdrawn. After healing of cutaneous necrosis low dose warfarin was started.

 NIPPV promote airway occlusion and improve hypercapnia.hypoxia and quality of life and reduced cardiovascular complications.