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Encyclopedia > Valsalva maneuver

In medicine, the Valsalva maneuver is performed by forcibly exhaling against closed lips and pinched nose, forcing air into the middle ear if the Eustachian tube is open. This maneuver with slight modifications can be used as a test of cardiac function and autonomic nervous control of the heart or to ‘clear’ the ears (equalize pressure) when external pressure increases, as in diving or aviation. This article is about the field and science of medical practice and health care. ... The middle ear is the portion of the ear internal to the eardrum, and external to the oval window of the cochlea. ... Anatomy of the human ear. ... This article or section is in need of attention from an expert on the subject. ... The heart and lungs, from an older edition of Grays Anatomy. ... Bat ears come in different sizes and shapes The ear is the sense organ that detects sound. ... Diving refers to the sport of acrobatically jumping or falling into water. ... Aviation refers to flying using aircraft, machines designed by humans for atmospheric flight. ...


The technique is named for Antonio Maria Valsalva, the 17th Century physician and anatomist from Bologna, whose principal scientific interest was the human ear. He described the Eustachian tube and the maneuver to test its patency. This article needs to be cleaned up to conform to a higher standard of quality. ... Bologna (IPA , from Latin Bononia, Bulåggna in the local dialect) is the capital city of Emilia-Romagna in northern Italy, in the Pianura Padana, between the Po River and the Apennines, exactly, between Reno River and Sàvena River. ...


Physiological response

Blood pressure (systolic and diastolic) and pulse rate during a normal response to Valsalva’s manoeuvre. Forty millimeter mercury pressure is applied at 5 seconds and relieved at 20 seconds.
Blood pressure (systolic and diastolic) and pulse rate during a normal response to Valsalva’s manoeuvre. Forty millimeter mercury pressure is applied at 5 seconds and relieved at 20 seconds.

The normal physiological response consists of 4 phases, which are marked on the figure at right: Image File history File linksMetadata Valsalva3. ... Image File history File linksMetadata Valsalva3. ...

  1. Initial pressure rise: On application of expiratory force, pressure rises inside the chest forcing blood out. This causes a transient rise in blood pressure.
  2. Reduced venous return and compensation: Return of blood to the heart is impeded by the pressure inside the chest. The output of the heart is reduced, the blood pressure falls. This occurs from 5 to about 14 seconds in the illustration. The fall in blood pressure reflexly causes blood vessels to constrict with some rise in pressure(15 to 20 seconds. This compensation can be quite marked with pressure returning to near or even above normal, but the cardiac output and blood flow to the body remains low. During this time the pulse rate increases.
  3. Pressure release: The pressure on the chest is released, allowing the pulmonary vessels and the aorta to re-expand causing a further initial slight fall in pressure (20 to 23 seconds) due to decreased left ventricular return and increased aortic volume, respectively. Venous blood can once more enter the chest and the heart, cardiac output begins to increase.
  4. Return of cardiac output: Blood return to the heart is enhanced by the effect of entry of blood which had been dammed back, causing a rapid increase in cardiac output and of blood pressure (24 seconds on). The pressure usually rises above normal before returning to a normal level. With return of blood pressure, the pulse rate returns towards normal.

Deviation from this response pattern signifies either abnormal heart function or abnormal autonomic nervous control of the heart. Cardiac output is the volume of blood being pumped by the heart, in particular a ventricle in a minute. ... The largest artery in the human body, the aorta originates from the left ventricle of the heart and brings oxygenated blood to all parts of the body in the systemic circulation. ...


Outside medicine

When rapid ambient pressure increase occurs as in diving or aircraft descent, this pressure tends to hold the Eustachian tubes closed, preventing pressure equalization across the ear drum, with painful results. To prevent this, divers, caisson workers and pilots ‘equalize’ pressure by swallowing, which tends to open the tubes. If this fails, then by blowing hard against closed lips and nose while swallowing. This is another application of the Valsalva maneuver. Anatomy of the human ear. ...


Straining, blowing against resistance as in blowing up balloons has a Valsalva effect and the fall in blood pressure can result in dizziness and even fainting.


  Results from FactBites:
 
Valsalva Maneuver | AHealthyMe.com (0 words)
The Valsalva maneuver is used with patients who have suspected heart abnormalities, often in conjunction with echocardiography.
The maneuver is based on the fact that when a patient forcibly exhales against a closed nose and mouth while bearing down, as if having a bowel movement, specific changes occur in blood pressure and the rate and volume of blood returning to the heart.
The Valsalva maneuver should not be performed on patients who have severe coronary artery disease, have experienced recent heart attack, or where there is a moderate to severe reduction in blood volume.
Valsalva maneuver (0 words)
Valsalva's initial intention for the maneuver was as a method of expressing pus from the middle ear.
A Valsalva maneuver performed against a closed glottis results in a drastic increase in pressure in the thoracic cavity, the airtight section of the torso that houses the lungs and heart.
The Valsalva maneuver is used as a pressure equalization technique by scuba divers and airplane passengers to avoid barotrauma and discomfort inside their ears when they move to a higher pressure breathing environment.
  More results at FactBites »

 
 

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