Valsalva maneuver

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Valsalva maneuver
Valsalva maneuver.jpg
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]

Contents

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 ]

History

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).

Physiological response

Blood pressure (systolic) and pulse rate during a normal response to a Valsalva maneuver. Forty-millimeter mercury pressure is applied at 5 seconds and relieved at 20 seconds. Valsalva3.jpg
Blood pressure (systolic) and pulse rate during a normal response to a Valsalva maneuver. Forty-millimeter mercury pressure is applied at 5 seconds and relieved at 20 seconds.

The normal physiological response consists of four phases. [3] [4]

  1. Initial pressure rise
    On application of expiratory force, pressure rises inside the chest forcing blood out of the pulmonary circulation into the left atrium. This causes a mild rise in stroke volume during the first few seconds of the maneuver.
  2. Reduced venous return and compensation
    Return of systemic blood to the heart is impeded by the pressure inside the chest. The output of the heart is reduced, and stroke volume falls. This occurs from 5 to about 14 seconds in the illustration. The fall in stroke volume reflexively causes blood vessels to constrict with some rise in pressure (15 to 20 seconds). This compensation can be marked with pressure returning to near or above normal, but the cardiac output and blood flow to the body remain low. During this time, the pulse rate increases (compensatory tachycardia).
  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 stroke volume (20 to 23 seconds) due to decreased left atrial return and increased aortic volume, respectively. Venous blood can once more enter the chest and the heart; cardiac output increases.
  4. Return of cardiac output
    Blood return to the heart is enhanced by the effect of the entry of blood that has been dammed back, causing a rapid increase in cardiac output (24 seconds on). The stroke volume usually rises above normal before returning to a normal level. With the return of blood pressure, the pulse rate returns to normal.

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.

Applications

Normalizing middle-ear pressures

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.

Strength training

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]

Pain management

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.

Regulation of heart rhythm

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]

Medical diagnostics

Cardiology

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
Decreases murmur
Aortic stenosis
Pulmonic stenosis
Tricuspid regurgitation
Increases murmur Hypertrophic cardiomyopathy
Mitral valve prolapse
Earlier onset of murmur
Mitral valve prolapse

Neurology

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]

Palpation of supraclavicular lymph nodes

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]

Oral–antral communication

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]

Urogenital medicine

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]

Complications

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]

Preretinal

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.

Valsalva device in spacesuits

Astronaut showing the use of the "Valsalva" Samantha Cristoforetti demonstrating Valsalva device.jpg
Astronaut showing the use of the "Valsalva"

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]

See also

Related Research Articles

<span class="mw-page-title-main">Tachycardia</span> Heart rate exceeding normal resting rate

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.

<span class="mw-page-title-main">Eustachian tube</span> Tube connecting middle ear to throat

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.

<span class="mw-page-title-main">Heart sounds</span> Noise generated by the beating heart

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.

<span class="mw-page-title-main">Heart murmur</span> Medical condition

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 either the systemic or the pulmonary circulation, with a corresponding state of hypotension in the other circulatory system. A shunt between the two systems will ensue if possible to reestablish the equilibrium.

<span class="mw-page-title-main">Palpitations</span> Perceived cardiac abnormality in which ones heartbeat can be felt

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<span class="mw-page-title-main">Hypovolemic shock</span> Medical emergency due to low blood volume

Hypovolemic shock is a form of shock caused by severe hypovolemia. It can be caused by severe dehydration or blood loss. Hypovolemic shock is a medical emergency; if left untreated, the insufficient blood flow can cause damage to organs, leading to multiple organ failure.

<span class="mw-page-title-main">Preload (cardiology)</span> Heart muscle stretch at rest

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.

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<span class="mw-page-title-main">Central venous pressure</span> Blood pressure in vein near the heart

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.

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<span class="mw-page-title-main">Ear clearing</span> Equalising of pressure in the middle ears

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.

The Nicoladoni–Branham sign is named after Carl Nicoladoni, who first noticed the phenomenon of the pulse slowing in a patient with right arm phlebarteriectasia when the brachialis artery proximal to it was compressed. In modern medicine, the sign is elicited when pressure is applied to an artery proximal to an arteriovenous fistula and said to be positive if the following occurs:

<span class="mw-page-title-main">Hypertrophic cardiomyopathy screening</span> Procedure for detecting a form of heart disease

Hypertrophic cardiomyopathy screening is an assessment and testing to detect hypertrophic cardiomyopathy (HCM).

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.

References

  1. 1 2 Taylor D (1996). "The Valsalva Manoeuvre: A critical review". South Pacific Underwater Medicine Society Journal. 26 (1). ISSN   0813-1988. OCLC   16986801. Archived from the original on May 8, 2008. Retrieved 14 March 2016.{{cite journal}}: CS1 maint: unfit URL (link)
  2. ↑ synd/2316 at Who Named It?
  3. 1 2 3 4 5 6 7 Srivastav S, Jamil RT, Zeltser R (2023), "Valsalva Maneuver", StatPearls, Treasure Island (FL): StatPearls Publishing, PMID   30725933 , retrieved 2023-10-25
  4. ↑ Luster EA, Baumgartner N, Adams WC, Convertino VA (1996). "Effects of hypovolemia and posture on responses to the Valsalva maneuver". Aviation, Space, and Environmental Medicine . 67 (4): 308–13. PMID   8900980.
  5. ↑ Brubakk A, Neuman T, eds. (2003). Bennett and Elliott's physiology and medicine of diving (5th Rev ed.). United States: Saunders Ltd. ISBN   978-0-7020-2571-6.[ page needed ]
  6. 1 2 3 Kay, E. "Prevention of middle ear barotrauma". Archived from the original on 27 April 2012. Retrieved 11 June 2008.
  7. ↑ Kay, E. "The Diver's Ear – Under Pressure". Archived from the original (Flash video) on 31 May 2012. Retrieved 11 June 2008.
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  16. ↑ Johnson RH, Smith AC, Spalding JM (1969). "Blood pressure response to standing and to Valsalva's manoeuvre: Independence of the two mechanisms in neurological diseases including cervical cord lesions". Clinical Science . 36 (1): 77–86. PMID   5783806.
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  24. ↑ "How Do I Manage Oroantral Communication? Key Points". 19 March 2013. Retrieved 13 October 2015.
  25. ↑ Cystoscopy and Urethroscopy in the Assessment of Urinary Incontinence at eMedicine
  26. ↑ Bump RC, Mattiasson A, Bø K, Brubaker LP, Delancey JO, Klarskov P, Shull BL, Smith AR (1996). "The standardization of terminology of female pelvic organ prolapse and pelvic floor dysfunction". American Journal of Obstetrics and Gynecology . 175 (1): 10–17. CiteSeerX   10.1.1.472.9918 . doi:10.1016/S0002-9378(96)70243-0. PMID   8694033.
  27. ↑ Gibran SK, Kenawy N, Wong D, Hiscott P (2007). "Changes in the retinal inner limiting membrane associated with Valsalva retinopathy". British Journal of Ophthalmology . 91 (5): 701–702. doi:10.1136/bjo.2006.104935. PMC   1954736 . PMID   17446519.
  28. ↑ Connor AJ (2010). "Valsalva-related retinal venous dilation caused by defaecation". Acta Ophthalmologica . 88 (4): e149. doi: 10.1111/j.1755-3768.2009.01624.x . PMID   19747224. S2CID   26590048.
  29. ↑ "US astronaut grapples with 'tears in space'". spacedaily.com. 25 May 2011. Retrieved 27 May 2011.
  30. ↑ Sam Cristoforetti [@AstroSamantha] (22 November 2011). "It's a Valsalva device, to equalize ears as the pressure in suit increases" (Tweet). Retrieved 22 November 2012– via Twitter.
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