Sudden Loss of Consciousness

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Syncope (a sudden loss of consciousness) is a common challenging and non-specific problem that may require medical intervention, especially in older individuals. Causes range from transient, benign, self-limited problems to life-threatening conditions. Patients who are evaluated in the emergency department for syncope are often admitted to the hospital. Nationally, about one percent of those evaluated in the ER are there for syncope, while up to about 35 percent of those patients are admitted. Patients admitted for syncope are usually placed on a cardiac monitoring unit and multiple tests are performed including MRIs, EKGs, EEGs, and cardiac catheterization. Despite all the testing, about 42 percent of those admitted for syncope have no cause found for their loss of consciousness by the time of discharge plus about 23 percent of those admitted for syncope are readmitted for the same diagnosis.

A recent study done in California looked at the medical records of those admitted for syncope. The mean age of these patients was 71 years. The main causes of primary (meaning no underlying disorder) syncope were rarely found. Those causes in descending order of frequency included hypokalemia (low potassium) at 0.24 percent, ventricular tachycardia (rapid heart rate), atrial fibrillation, dehydration, and hyponatremia (low sodium). The most common causes of secondary syncope were heart disease and cancer.

Fortunately, mortality from syncope is very low with mortality from primary syncope at 0.2 percent and secondary syncope at 1.4 percent. Higher mortality from secondary syncope was associated with congestive heart failure, interstitial lung disease, pulmonary hypertension, end-stage kidney disease, and metastatic cancer. Hospital costs associated with admissions for syncope have risen from $20,023 in 2005 to $28,175 in 2011 and the average admission is for two days. Higher costs were associated with implanted defibrillator and pacemaker placements, cardiac catheterization, and other expensive tests and procedures. In the study nearly a quarter of patients had multiple admissions for syncope with no diagnosis being found. The authors rightly point out that this constitutes an inefficient use of resources.

The study concludes with the authors’ opinion that the rising costs of hospital admissions for syncope and the rising number of admissions for syncope, especially multiple admissions for some patients, plus the fact that nearly half of those admitted for primary syncope have no cause found, should lead the medical community to question the wisdom of hospital admission for primary syncope. They question the need for admission especially after the emergency room work-up is normal.

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