Hypovolemia forms

In sinus bradycardia or incomplete heart block, lidocaine administration for the elimination of ventricular ectopy without prior acceleration in heart rate (eg, by atropine, isoproterenol or electric pacing) may promote more frequent and serious ventricular arrhythmias or complete heart block. Use with caution in patients with hypovolemia and shock, and all forms of heart block. 

Shock is a complex acute cardiovascular syndrome that results in a critical reduction in perfusion of vital tissues and a wide range of systemic effects. Shock is usually associated with hypotension, an altered mental state, oliguria, and metabolic acidosis. If untreated, shock usually progresses to a refractory deteriorating state and death. The three major mechanisms responsible for shock are hypovolemia, cardiac insufficiency, and altered vascular resistance. Volume replacement and treatment of the underlying disease are the mainstays of the treatment of shock. Although sympathomimetic drugs have been used in the treatment of virtually all forms of shock, their efficacy is unclear. 

Hydrolyzes in mucous membrane water to form hydrochloric acid, damaging respiratory tract epithelial cells and eyes and also causing hemoconcentration, hypovolemia, hypoxia, liver necrosis, pulmonary necrosis, and renal necrosis... 

In dehydration, fluid volume is also decreased, but there is an increase in the osmolality of the blood because an equivalent amount of sodium was not lost. This form of hypovolemia occurs when fluid is lost but not replaced because the individual is unable to drink (e.g., an infant, an unconscious child or adult, or someone stranded without access to drinkable water) or did not experience the normal thirst impulse (e.g., elderly persons). The result would be a loss of water without replacement and without an equal loss of sodium, resulting in an elevation in sodium concentration in the blood and increased serum osmolality. Dehydration can occur through such mechanisms as profuse sweating, diuresis (e.g., in diabetes insipidus [deficient ADH] or diabetes mellitus and osmotic fluid loss), or excessive diuretic use. 2... 

Depending on the type of fluid loss and replacement of fluids, hypovolemia can be one of three forms (relative to the sodium loss) ... 

Symptoms of overt beriberi are usually abrupt with presentation of left ventricular cardiac and peripheral vascular failure yielding water retention due to stimulation of the renin-angiotensin-aldosterone axis by hypovolemia, as well as striated and smooth muscles weakness in the wet form of the disease. At this stage of the disease, the clinical diagnosis is usually apparent but outcome of the supplementary treatment with thiamine may be poor, due to irreversible alterations in muscles and the central nervous system (CNS). 

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