Shock means tissues are starving for blood flow
Circulatory shock is not emotional jolt—it is insufficient blood reaching body tissues. Early signs can be weakness, racing pulse, fast breathing, sweat, anxiety, and thirst. Untreated, confusion, unconsciousness, or cardiac arrest may follow. Clinicians sort it into four cause-based types.
Shock is defined as inadequate blood flow to tissues from circulatory failure. Diagnosis blends symptoms, exam, and labs; narrowed pulse pressure or tachycardia raises concern. Presentation varies: some people show mainly confusion and weakness, and low blood pressure, low urine output, or confusion are not always present. Heart rate is often fast, yet beta-blockers, athletic conditioning, or about 30 percent of intra-abdominal bleeding cases can keep it normal or slow. Early clues include dry mucous membranes, poor skin turgor, delayed capillary refill, weak peripheral pulses, and cold extremities. Sources describe it as a medical emergency needing urgent care.
Four main types track the underlying problem. Hypovolemic, or low-volume, shock is the most common, often from hemorrhage; in children, vomiting and diarrhea lead. Burns and excess urine loss in diabetic ketoacidosis or diabetes insipidus also deplete volume. Cardiogenic shock follows pump failure—commonly a large myocardial infarction, but also arrhythmias, myocarditis, heart failure, contusion, or valve disease. Obstructive shock stems from physical blockage of great vessels: cardiac tamponade, tension pneumothorax, pulmonary embolism, severe aortic stenosis, or abdominal compartment syndrome with pressure over 20 mmHg plus organ dysfunction. Distributive shock dilates vessels widely via sepsis, anaphylaxis, or high spinal injury.
Septic shock is the leading distributive form, with infection-driven vasodilation and hypotension; a 1992 consensus defined sepsis-induced low pressure that persists despite fluids plus perfusion problems such as lactic acidosis, oliguria, or mental change. Anaphylactic shock follows allergen exposure with histamine-driven vessel leak and signs like hives and swelling. Neurogenic shock after high spinal injury classically pairs slow heart rate with warm skin from lost sympathetic tone—distinct from spinal shock's temporary cord dysfunction. Hypovolemic pictures often include a rapid thready pulse, cool mottled skin, shallow rapid breathing, and thirst. Shock index—heart rate divided by systolic pressure—can outpredict rate or pressure alone for blood-loss impact, though pregnancy-related bleeding is less well studied.
Source: Shock (circulatory)
