Volumutvidelse

Volumutvidelse, or volume expansion, is the medical term for increasing the volume of body fluids or a body compartment, most commonly the intravascular space (plasma). It is a central component of fluid therapy aimed at restoring tissue perfusion and oxygen delivery after fluid loss due to injury, surgery, dehydration, or sepsis.

Volume expansion is achieved with intravenous fluids or blood products. Crystalloids such as isotonic saline or balanced solutions (for example lactated Ringer’s) rapidly expand the extracellular fluid and intravascular volume. Colloids (such as albumin, gelatin, or dextrans) are designed to remain in the vascular space longer but carry specific risks and may not always be superior. Transfusion of red blood cells or plasma is used when volume needs to be increased alongside oxygen-carrying capacity or coagulation factors.

Indications include hypovolemia, hemorrhagic shock, severe dehydration, septic shock, major surgery, and other states of reduced effective circulating volume. Administration is typically started with small boluses, followed by reassessment to reach hemodynamic targets and ensure adequate organ perfusion.

Monitoring and risks: Response is monitored by blood pressure, heart rate, urine output, mental status, capillary refill, and dynamic assessments such as stroke volume variation or echocardiography. Risks include fluid overload leading to edema or pulmonary edema, electrolyte disturbances, and, for certain colloids or blood products, transfusion reactions or kidney injury.

Practical approach: Modern practice prioritizes balanced crystalloids, careful assessment of fluid responsiveness, and avoidance of unnecessary overload, with choices tailored to patient condition and comorbidities.

See also: fluid therapy, resuscitation, hypovolemia.