Physiological inability to close the eyelids during sleep (nocturnal lagophthalmos) may also cause exposure keratopathy. Mechanical causes
Chemical or thermal burns to eyelids or conjunctiva, ocular cicatricial pemphigoid, or symblepharon may cause incomplete or inadequate eyelid closure. Exophthalmos
Exophthalmos  is the unilateral or bilateral bulging of the eye anteriorly out of the orbit causing increased exposure of cornea. It may be seen in many conditions like Graves ophthalmopathy, Orbital cellulitis, Orbital pseudotumor etc. Surgical
A weak bell phenomenon may result in exposure keratopathy after ptosis surgery. Postoperative lagophthalmos following blepharoplasty is another common cause of secondary exposure keratopathy. Diagnosis
Fluorescein staining may be used to detect for epithelial defects, corneal infection or perforation of the cornea. Tear break-up time and ocular protection index assessment can be done to reveal dry eye. Exophthalmometry can be used to measure degree of exophthalmos. Prevention
If increased corneal exposure is detected, several preventive measures can be done to prevent keratitis. Aritificial eye drops and eye ointments may be used to keep the eyes moist. Since frequent use of eye drops with preservatives can promote inflammation, it is better to choose preservative free artificial tear drops and lubricating eye drops. Bandage silicone hydrogel or scleral contact lens may be used to protect cornea. But, risk of infection is more  with bandage contact lens use. Moisture goggles may also be used to protect cornea. Temporary or permanent tarsorrhaphy may be indicated to treat lagophthalmos. Gold weights can be inserted into the upper eyelid to treat fasial nerve palsy.
Intrathoracic space competition from heart enlargement and pulmonary edema (complications of CHF) that compress airway construction and bronchioles. Bronchial obstruction secondary to intraluminal edema. Bronchial mucosa edema. Diagnosis
The diagnosis of cardiac asthma is accomplished through workup of congestive heart failure, complete with:

Evaluation of current symptoms with specific consideration of chronological progression or worsening. Past Medical History screen with consideration for conditions that predispose to heart failure, such as prior heart attack, history of coronary revascularization, high blood pressure, or diabetes (heart). Physical Exam with emphasis on listening for abnormalities of heart sound, abnormalities of lung sound, or presence of increased fluid retention in neck or in extremities. Laboratory Evaluation with specific interest in B-type natriuretic peptide levels. Electrocardiography to evaluate for irregularities in heart rhythm. Chest Radiograph to evaluate for presence of lung congestion or increased heart size. Echocardiography to evaluate heart function. Echocardiography is the preferred choice for diagnosis of heart failure in patients.As well as evaluation of lung function via:

Pulmonary function testing (PFT) complete with bronchoprovocation testing. PFTs represent the preferred method for evaluating for bronchial asthma. Management
Treatment of asthma symptoms in CHF patients is directed towards optimizing the patients cardiovascular status and correcting potential oxygen deficit. Current recommendations in acute asthma symptoms are utilization of diuretics such as furosemide, venodilators such as nitroglycerin, and morphine. The initial strategy should focus on decreasing patient fluid retention with diuretic therapy, thereby decreasing cardiac preload and overall fluid load in pulmonary circuit (pulmonary congestion).