Passive leg raising test
Encyclopedia
In medicine
, the passive leg raising test is a bedside test to evaluate the need for further fluid resuscitation in critically ill
patients.
The test involves raising the legs of a patient (without his active participation), which causes gravity to pull blood
from the legs, thus increasing circulatory volume
available to the heart
(cardiac preload) by around 500 milliliters. The real-time effects of this manoeuvre on haemodynamic parameters such as blood pressure
and heart rate
are used to guide the decision whether or not more fluid will be beneficial. The assessment is easier when invasive monitoring is present (such as an arterial catheter).
The manoeuvre might be reinforced in a clinical setting by moving the patient's bed from a semi-recumbent position to a recumbent position with the legs raised. This is theorised to cause an additional mobilisation of blood from the gastrointestinal circulation.
Several studies showed that this measure is a better predictor of response to rapid fluid loading than other tests such as respiratory variation in pulse pressure or echocardiographic
markers.
Medicine
Medicine is the science and art of healing. It encompasses a variety of health care practices evolved to maintain and restore health by the prevention and treatment of illness....
, the passive leg raising test is a bedside test to evaluate the need for further fluid resuscitation in critically ill
Intensive care medicine
Intensive-care medicine or critical-care medicine is a branch of medicine concerned with the diagnosis and management of life threatening conditions requiring sophisticated organ support and invasive monitoring.- Overview :...
patients.
The test involves raising the legs of a patient (without his active participation), which causes gravity to pull blood
Blood
Blood is a specialized bodily fluid in animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells....
from the legs, thus increasing circulatory volume
Volume status
In medicine, intravascular volume status refers to the volume of blood in a patient's circulatory system, and is essentially the blood plasma component of the overall volume status of the body, which otherwise includes both intracellular fluid and extracellular fluid...
available to the heart
Heart
The heart is a myogenic muscular organ found in all animals with a circulatory system , that is responsible for pumping blood throughout the blood vessels by repeated, rhythmic contractions...
(cardiac preload) by around 500 milliliters. The real-time effects of this manoeuvre on haemodynamic parameters such as blood pressure
Blood pressure
Blood pressure is the pressure exerted by circulating blood upon the walls of blood vessels, and is one of the principal vital signs. When used without further specification, "blood pressure" usually refers to the arterial pressure of the systemic circulation. During each heartbeat, BP varies...
and heart rate
Heart rate
Heart rate is the number of heartbeats per unit of time, typically expressed as beats per minute . Heart rate can vary as the body's need to absorb oxygen and excrete carbon dioxide changes, such as during exercise or sleep....
are used to guide the decision whether or not more fluid will be beneficial. The assessment is easier when invasive monitoring is present (such as an arterial catheter).
The manoeuvre might be reinforced in a clinical setting by moving the patient's bed from a semi-recumbent position to a recumbent position with the legs raised. This is theorised to cause an additional mobilisation of blood from the gastrointestinal circulation.
Several studies showed that this measure is a better predictor of response to rapid fluid loading than other tests such as respiratory variation in pulse pressure or echocardiographic
Echocardiography
An echocardiogram, often referred to in the medical community as a cardiac ECHO or simply an ECHO, is a sonogram of the heart . Also known as a cardiac ultrasound, it uses standard ultrasound techniques to image two-dimensional slices of the heart...
markers.