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Valsalva maneuver | |
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![]() A man performs the Valsalva maneuver while his ear is examined with an otoscope. |
The Valsalva maneuver is performed by a forceful attempt of exhalation against a closed airway, usually done by closing one's mouth and pinching one's nose shut while expelling air, as if blowing up a balloon. Variations of the maneuver can be used either in medical examination as a test of cardiac function and autonomic nervous control of the heart, or to clear the ears and sinuses (that is, to equalize pressure between them) when ambient pressure changes, as in scuba diving, hyperbaric oxygen therapy, or air travel. [1]
A modified version is done by expiring against a closed glottis. This will elicit the cardiovascular responses described below but will not force air into the Eustachian tubes.[ citation needed ]
The technique is named after Antonio Maria Valsalva, [2] [3] a 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 (openness).
The normal physiological response consists of four phases. [3] [4]
In summary, the maneuver increases intrathoracic pressure and, thus, a decrease in preload to the heart. This decreased preload leads to cardiovascular changes through the baroreflex and other compensatory reflex mechanisms. [3] Deviation from this response pattern signifies either abnormal heart function or abnormal autonomic nervous control of the heart. Dentists also use Valsalva following extraction of a maxillary molar tooth. The maneuver is performed to determine if there is a perforation or antral communication.
When rapid ambient pressure increase occurs, as in underwater diving or aircraft descent, this pressure tends to hold the Eustachian tubes closed, preventing pressure equalization across the eardrum and causing pain. [5] [6] [7] To avoid this painful situation, divers, caisson workers and people in pressurised aircraft attempt to open the Eustachian tubes by swallowing, which tends to open the tubes, allowing the ear to equalize itself.[ citation needed ]
If this fails, then the Valsalva maneuver may be used. This maneuver, when used as a tool to equalize middle ear pressure, carries with it the risk of auditory damage from over-pressurization of the middle ear. [1] [6] [8] The Valsalva maneuver generates about 20–40 mm of Hg pressure. [9] It is safer, if time permits, to attempt to open the Eustachian tubes by swallowing a few times, or yawning, or by using the Valsalva technique of breathing a minimal amount of air gently into nostrils held closed by the fingers as soon as mild pressure is felt before it increases to the point that its release would be painful. The effectiveness of the "yawning" method can be improved with practice; some people can achieve release or opening by moving their jaw forward or forward and down, rather than straight down as in a classical yawn, [6] and some can do so without moving their jaw at all by activating the tensor tympani muscle, which is heard by the individual as a deep, rumbling sound.
During swallowing or yawning, several muscles in the pharynx (throat) elevate the soft palate and open the throat. One of these muscles, the tensor veli palatini, also acts to open the Eustachian tube. This is why swallowing or yawning is successful in equalizing middle ear pressure. Contrary to popular belief, the jaw does not pinch the tubes shut when closed. The Eustachian tubes are not located close enough to the mandible to be pinched off. People often recommend chewing gum during ascent/descent in aircraft because chewing gum increases the rate of salivation, and swallowing the excess saliva opens the Eustachian tubes.
In a clinical setting, the Valsalva maneuver is commonly done against a closed glottis or an external pressure measuring device, thus eliminating or minimizing the pressure on the Eustachian tubes. Straining or 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.
The Valsalva maneuver is commonly believed to be the optimal breathing pattern for producing maximal force. It is frequently used in powerlifting to stabilize the trunk during exercises such as the squat, deadlift, and bench press, and in both lifts of Olympic weightlifting. [10]
The Valsalva maneuver can reduce pain during lumbar puncture. [11] [ how? ] According to Kumar, et al., performing the maneuver on an awake patient triggers predictable cardiovascular and autonomic responses that can be timed by a skilled surgeon to maximize anesthetic benefit for the patient.
The Valsalva maneuver may be used to arrest episodes of supraventricular tachycardia. [12] [13] Blood pressure (BP) rises at onset of straining-because the increased intrathoracic pressure (ITP) is added to the pressure in the aorta. It then falls because the ITP compresses the veins, decreasing the venous return and cardiac output. This inhibits the baroreceptors, causing tachycardia and a rise in peripheral vascular resistance (PVR). When the glottis is opened and the ITP returns to normal, cardiac output is restored, but the peripheral vessels are constricted. The blood pressure therefore rises above normal, and this stimulates the baroreceptors, causing bradycardia and a drop in BP to a normal level. [14]
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The maneuver can sometimes be used to diagnose heart abnormalities, especially when used in conjunction with an echocardiogram. [15] [ unreliable medical source? ] For example, the Valsalva maneuver (phase II) increases the intensity of hypertrophic cardiomyopathy murmurs, namely those of dynamic subvalvular left ventricular outflow obstruction. This is due to the decreased preload in this phase, worsening the obstruction and thus accentuating the murmur. [3] At the same time, the Valsalva maneuver (phase II) decreases the intensity of most other murmurs, including those resulting from aortic stenosis and atrial septal defect. The decrease in murmur intensity occurs from a smaller preload, which reduces the amount of blood ejected through the stenotic aortic valve, thereby decreasing murmur intensity. [3]
Effect of Valsalva (phase II) | Cardiac finding |
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Decreases murmur | |
Aortic stenosis | |
Pulmonic stenosis | |
Tricuspid regurgitation | |
Increases murmur | Hypertrophic cardiomyopathy |
Mitral valve prolapse | |
Earlier onset of murmur | |
Mitral valve prolapse |
The Valsalva maneuver is used to aid in the clinical diagnosis of problems or injuries in the nerves of the cervical spine. [16] Upon performing the Valsalva maneuver, intraspinal pressure slightly increases. Thus, neuropathies or radicular pain may be felt or exacerbated, which may indicate nerve impingement by an intervertebral disc or other part of the anatomy. Headache and pain upon performing the Valsalva maneuver are also one of the main symptoms in Arnold–Chiari malformation. The Valsalva maneuver may help check for a dural tear following certain spinal operations, such as a microdiscectomy. An increase in intra-spinal pressure will cause cerebral spinal fluid (CSF) to leak out of the dura, causing a headache.[ citation needed ]
The Valsalva maneuver has been associated with transient global amnesia. [17] [18] [19] [20] [21]
As the lymph nodes may be buried, asking the patient to perform the Valsalva maneuver can push the cupola of the lung upward, bringing deep-seated nodes to a more accessible position for palpation. [22] Palpation may identify an enlargement of the supraclavicular lymph nodes, a diagnostic indicator of cancer. The prevalence of malignancy in the presence of supraclavicular lymphadenopathy is reported to be in the range of 54% to 85%. [23]
A variant of the Valsalva maneuver is used to aid diagnosis of oral–antral communication, i.e., the existence of a connection between the oral cavity and the maxillary sinus. [24]
The Valsalva maneuver is used to aid in the diagnosis of intrinsic sphincteric deficiency (ISD) in urodynamic tests. Valsalva leak point pressure is the minimum vesicular pressure associated with urine leakage. Although there is no consensus on the threshold value, values > 60 cm H2O are commonly considered to indicate hypermobility of the bladder neck and normal sphincter function. [25] Also, when examining women with pelvic organ prolapse, asking the patient to perform the Valsalva maneuver is used to demonstrate maximum pelvic organ descent. [26]
The Valsalva maneuver is relatively safe, and side effects are rare. Yet, complications include Valsalva retinopathy in susceptible patients. There are also reports of syncope, chest pain, and arrhythmias due to the performance of the maneuver, so caution is necessary for patients with preexisting coronary artery disease, valvular heart disease, or congenital heart defects. [3]
Valsalva retinopathy is pathological syndrome associated with the Valsalva maneuver. [27] [28] [3] It presents as preretinal hemorrhage (bleeding in front of the retina) in people with a history of transient increase in the intrathoracic pressure and may be associated with heavy lifting, forceful coughing, straining on the toilet, or vomiting. The bleeding may cause visual loss if it obstructs the visual axis, and patients may note floaters in their visual field. Usually, this causes no permanent visual impairments, and sight is fully restored.
Some spacesuits contain a device called the Valsalva device to enable the wearer to block their nose to perform the Valsalva maneuver when wearing the suit. Astronaut Drew Feustel describes it as "a spongy device called a Valsalva that is typically used to block the nose in case a pressure readjustment is needed". [29] One use of the device is to equalize pressure during suit pressurization. [30]
Tachycardia, also called tachyarrhythmia, is a heart rate that exceeds the normal resting rate. In general, a resting heart rate over 100 beats per minute is accepted as tachycardia in adults. Heart rates above the resting rate may be normal or abnormal.
The Eustachian tube, also called the auditory tube or pharyngotympanic tube, is a tube that links the nasopharynx to the middle ear, of which it is also a part. In adult humans, the Eustachian tube is approximately 35 mm (1.4 in) long and 3 mm (0.12 in) in diameter. It is named after the sixteenth-century Italian anatomist Bartolomeo Eustachi.
Heart sounds are the noises generated by the beating heart and the resultant flow of blood through it. Specifically, the sounds reflect the turbulence created when the heart valves snap shut. In cardiac auscultation, an examiner may use a stethoscope to listen for these unique and distinct sounds that provide important auditory data regarding the condition of the heart.
Heart murmurs are unique heart sounds produced when blood flows across a heart valve or blood vessel. This occurs when turbulent blood flow creates a sound loud enough to hear with a stethoscope. The sound differs from normal heart sounds by their characteristics. For example, heart murmurs may have a distinct pitch, duration and timing. The major way health care providers examine the heart on physical exam is heart auscultation; another clinical technique is palpation, which can detect by touch when such turbulence causes the vibrations called cardiac thrill. A murmur is a sign found during the cardiac exam. Murmurs are of various types and are important in the detection of cardiac and valvular pathologies.
In cardiovascular physiology, stroke volume (SV) is the volume of blood pumped from the ventricle per beat. Stroke volume is calculated using measurements of ventricle volumes from an echocardiogram and subtracting the volume of the blood in the ventricle at the end of a beat from the volume of blood just prior to the beat. The term stroke volume can apply to each of the two ventricles of the heart, although when not explicitly stated it refers to the left ventricle and should therefore be referred to as left stroke volume (LSV). The stroke volumes for each ventricle are generally equal, both being approximately 90 mL in a healthy 70-kg man. Any persistent difference between the two stroke volumes, no matter how small, would inevitably lead to venous congestion of and/or shunt between the systemic and the pulmonary circulation.
Palpitations are perceived abnormalities of the heartbeat characterized by awareness of cardiac muscle contractions in the chest, which is further characterized by the hard, fast and/or irregular beatings of the heart.
Antonio Maria Valsalva, was an Italian anatomist born in Imola. His research focused on the anatomy of the ears. He coined the term Eustachian tube and he described the aortic sinuses of Valsalva in his writings, published posthumously in 1740. His name is associated with the Valsalva antrum of the ear and the Valsalva maneuver, which is used as a test of circulatory function. Anatomical structures bearing his name are Valsalva’s muscle and taeniae Valsalvae. He observed that when weakness of one side of the body is caused by a lesion in the brain, the culprit lesion tends to be on the side opposite (contralateral) to the weak side; this finding is named the "Valsalva doctrine" in his honor.
In cardiac physiology, preload is the amount of sarcomere stretch experienced by cardiac muscle cells, called cardiomyocytes, at the end of ventricular filling during diastole. Preload is directly related to ventricular filling. As the relaxed ventricle fills during diastole, the walls are stretched and the length of sarcomeres increases. Sarcomere length can be approximated by the volume of the ventricle because each shape has a conserved surface-area-to-volume ratio. This is useful clinically because measuring the sarcomere length is destructive to heart tissue. It requires cutting out a piece of cardiac muscle to look at the sarcomeres under a microscope. It is currently not possible to directly measure preload in the beating heart of a living animal. Preload is estimated from end-diastolic ventricular pressure and is measured in millimeters of mercury (mmHg).
Pulsus paradoxus, also paradoxic pulse or paradoxical pulse, is an abnormally large decrease in stroke volume, systolic blood pressure and pulse wave amplitude during inspiration. Pulsus paradoxus is not related to pulse rate or heart rate, and it is not a paradoxical rise in systolic pressure. Normally, blood pressure drops less precipitously than 10 mmHg during inhalation. Pulsus paradoxus is a sign that is indicative of several conditions, most commonly pericardial effusion.
Cardiac asthma is the medical condition of intermittent wheezing, coughing, and shortness of breath that is associated with underlying congestive heart failure (CHF). Symptoms of cardiac asthma are related to the heart's inability to effectively and efficiently pump blood in a CHF patient. This can lead to accumulation of fluid in and around the lungs, disrupting the lung's ability to oxygenate blood.
Central venous pressure (CVP) is the blood pressure in the venae cavae, near the right atrium of the heart. CVP reflects the amount of blood returning to the heart and the ability of the heart to pump the blood back into the arterial system. CVP is often a good approximation of right atrial pressure (RAP), although the two terms are not identical, as a pressure differential can sometimes exist between the venae cavae and the right atrium. CVP and RAP can differ when arterial tone is altered. This can be graphically depicted as changes in the slope of the venous return plotted against right atrial pressure.
An embolus, is described as a free-floating mass, located inside blood vessels that can travel from one site in the blood stream to another. An embolus can be made up of solid, liquid, or gas. Once these masses get "stuck" in a different blood vessel, it is then known as an "embolism." An embolism can cause ischemia—damage to an organ from lack of oxygen. A paradoxical embolism is a specific type of embolism in which the embolus travels from the right side of the heart to the left side of the heart and lodges itself in a blood vessel known as an artery. Thus, it is termed "paradoxical" because the embolus lands in an artery, rather than a vein.
Ear clearing, clearing the ears or equalization is any of various maneuvers to equalize the pressure in the middle ear with the outside pressure, by letting air enter along the Eustachian tubes, as this does not always happen automatically when the pressure in the middle ear is lower than the outside pressure. This need can arise in scuba diving, freediving/spearfishing, skydiving, fast descent in an aircraft, fast descent in a mine cage, and being put into pressure in a caisson or similar internally pressurised enclosure, or sometimes even simply travelling at fast speeds in an automobile.
Venous return is the rate of blood flow back to the heart. It normally limits cardiac output.
The Frenzel Maneuver is named after Hermann Frenzel. The maneuver was developed in 1938 and originally was taught to dive bomber pilots during World War II. The maneuver is used to equalize pressure in the middle ear. Today, the maneuver is also performed by scuba divers, free divers and by passengers on aircraft as they descend.
Obstructive shock is one of the four types of shock, caused by a physical obstruction in the flow of blood. Obstruction can occur at the level of the great vessels or the heart itself. Causes include pulmonary embolism, cardiac tamponade, and tension pneumothorax. These are all life-threatening. Symptoms may include shortness of breath, weakness, or altered mental status. Low blood pressure and tachycardia are often seen in shock. Other symptoms depend on the underlying cause.
Hypertrophic cardiomyopathy screening is an assessment and testing to detect hypertrophic cardiomyopathy (HCM).
The handgrip maneuver is performed by clenching one's fist forcefully for a sustained time until fatigued. Variations include squeezing an item such as a rolled up washcloth.
Eustachian tube dysfunction (ETD) is a disorder where pressure abnormalities in the middle ear result in symptoms.
Middle ear barotrauma (MEBT), also known to underwater divers as ear squeeze and reverse ear squeeze, is an injury caused by a difference in pressure between the external ear canal and the middle ear. It is common in underwater divers and usually occurs when the diver does not equalise sufficiently during descent or, less commonly, on ascent. Failure to equalise may be due to inexperience or eustachian tube dysfunction, which can have many possible causes. Unequalised ambient pressure increase during descent causes a pressure imbalance between the middle ear air space and the external auditory canal over the eardrum, referred to by divers as ear squeeze, causing inward stretching, serous effusion and haemorrhage, and eventual rupture. During ascent internal over-pressure is normally passively released through the eustachian tube, but if this does not happen the volume expansion of middle ear gas will cause outward bulging, stretching and eventual rupture of the eardrum known to divers as reverse ear squeeze. This damage causes local pain and hearing loss. Tympanic rupture during a dive can allow water into the middle ear, which can cause severe vertigo from caloric stimulation. This may cause nausea and vomiting underwater, which has a high risk of aspiration of vomit or water, with possibly fatal consequences.
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