Pulseless electrical activity (PEA) refers to cardiac arrest in which the electrocardiogram shows a heart rhythm that should produce a pulse, but does not. Pulseless electrical activity is found initially in about 55% of people in cardiac arrest.Under normal circumstances, electrical activation of muscle cells precedes mechanical contraction of the heart (known as electromechanical coupling). In PEA, there is electrical activity but insufficient cardiac output to generate a pulse and supply blood to the organs, whether the heart itself is failing to contract or otherwise. While PEA is classified as a form of cardiac arrest, significant cardiac output may still be present, which may be determined and best visualized by bedside ultrasound (echocardiography). Cardiopulmonary resuscitation (CPR) is the first treatment for PEA, while potential underlying causes are identified and treated. The medication epinephrine (aka adrenaline) may be administered. Survival is about 20%. Signs and symptoms
Pulseless electrical activity leads to a loss of cardiac output, and the blood supply to the brain is interrupted. As a result, PEA is usually noticed when a person loses consciousness and stops breathing spontaneously. This is confirmed by examining the airway for obstruction, observing the chest for respiratory movement, and feeling the pulse (usually at the carotid artery) for a period of 10 seconds. Causes
These possible causes are remembered as the 6 Hs and the 6 Ts.
Xanthelasma is a sharply demarcated yellowish deposit of cholesterol underneath the skin. It usually occurs on or around the eyelids (xanthelasma palpebrarum, abbreviated XP). While they are neither harmful to the skin nor painful, these minor growths may be disfiguring and can be removed. There is a growing body of evidence for the association between xanthelasma deposits and blood low-density lipoprotein levels and increased risk of atherosclerosis.A xanthelasma may be referred to as a xanthoma when becoming larger and nodular, assuming tumorous proportions. Xanthelasma is often classified simply as a subtype of xanthoma. Diagnosis
Xanthelasma in the form of XP can be diagnosed from clinical impression, although in some cases it may need to be distinguished (differential diagnosis) from other conditions, especially necrobiotic xanthogranuloma, syringoma, palpebral sarcoidosis, sebaceous hyperplasia, Erdheim–Chester disease, lipoid proteinosis (Urbach–Wiethe disease), and the syndrome of adult-onset asthma and periocular xanthogranuloma (AAPOX). Differential diagnosis can be accomplished by surgical excision followed by microscopic examination by a pathologist (biopsy to determine histopathology). The typical clinical impression of XP is soft, yellowish papules, plaques, or nodules, symmetrically distributed on the medial side of the upper eyelids; sometimes the lower eyelids are affected as well. Treatment
Xanthelasmata can be removed with a trichloroacetic acid peel, surgery, lasers or cryotherapy. Removal may cause, although uncommon, scarring and pigment changes. Prognosis
Recurrence is common: 40% of patients with XP had recurrence after primary surgical excision, 60% after secondary excision, and 80% when all four eyelids were involved. A possible cause might be insufficiently deep excisions.