hyperventilation syndrome (HVS)



OVERVIEW

  • A group of syndromes caused by hyperventilation in excess of physiological metabolic requirements.
  • Main manifestations include chest tightness, dyspnea, palpitation, chest pain, anxiety, depression, dizziness, etc.
  • The etiology is unknown and may be related to psychological factors.
  • Abdominal breathing training, drug therapy, cognitive behavioral therapy are mainly used.
  • Definition

  • Hyperventilation syndrome is a group of syndromes caused by hyperventilation in excess of physiologic and metabolic needs, and its clinical symptoms can be induced by hyperventilation provocation test [1].
  • Hyperventilation syndrome may present with clinical manifestations such as chest tightness and breath-holding, dyspnea, palpitations, chest pain, anxiety, depression, dizziness, lightheadedness, and fainting.
  • Morbidity

  • The disease is prevalent in females, and women account for the majority of cases with onset under 25 years of age [2].
  • Hyperventilation syndrome accounts for 10% of outpatients in our country [1].
  • Etiology

    Causes

    The etiology of hyperventilation syndrome is unknown, and it may be related to psychological factors such as history of trauma, excessive fatigue, mental stress, and excessive psychological pressure.

    Pathogenesis

  • Hypoxia, low cardiac output caused by cardiopulmonary disorders, fever, drugs and other adverse stimuli and other neurological and psychiatric factors can increase respiratory drive through negative feedback regulation of peripheral chemoreceptors or stimulation of brainstem respiratory nerves by cortical structures, which may manifest as hyperventilation.
  • Abnormalities in partial pressure of carbon dioxide (PaCO2), partial pressure of oxygen (PO2), and pH can act on brainstem respiratory centers through peripheral and central chemoreceptors, causing corresponding changes in ventilation.
  • Patients with hyperventilation syndrome have abnormalities in the pre-feedback regulation of the higher central nervous system, and hyperventilation in excess of physiologic metabolic needs can occur when induced by factors such as anxiety and stress.
  • Hyperventilation exhales large amounts of carbon dioxide, PaCO2 decreases rapidly, plasma bicarbonate decreases relatively, and the body compensates by two pathways to maintain constant pH, the buffering system of extracellular fluid and renal compensation. Buffering regulation by extracellular fluid is very limited, and renal compensation takes several days, so that hypocapnia and respiratory alkalosis occur almost immediately.
  • The most immediate and serious danger of hypocapnia is cerebral vasoconstriction, resulting in decreased cerebral blood flow and cerebral hypoxia. Cerebral hypoxia triggers neurologic symptoms such as dizziness, blurred vision and even fainting. Alkalemia secondary to decreased serum free calcium can result in numbness, spasms and convulsions of the hands, feet and upper and lower extremities. Severe alkalemia may cause myocardial hypoxia and cardiac arrhythmia.
  • Symptoms

    Main Symptoms

    Hyperventilation syndrome may present with respiratory symptoms, cardiovascular symptoms, and psychoneurologic symptoms.

    Respiratory symptoms

  • Chest tightness and breath-holding: manifested by labored breathing or insufficient air.
  • Dyspnea: a feeling of insufficient air or labored breathing. Showing changes in respiratory rate, rhythm and depth.
  • Foreign body sensation in the throat: a foreign body sensation in the throat, such as a feeling of obstruction, constriction and itching.
  • Cardiovascular System Symptoms

  • Palpitations: Feeling of enhanced and accelerated heartbeat, sometimes even the sensation of hitting the chest wall, or feeling empty inside.
  • Chest pain: mostly manifested as dull pain in the precordial region, or instantaneous sharp knife-cutting pain in the precordial region or the left rib arch edge, and often radiating to the neck and back, which may last for several minutes to several hours.
  • Psychiatric Symptoms

  • Nervousness, anxiety, depression.
  • Fear, near-death feeling, etc.
  • Nervous system symptoms

  • Darkening of the eyes and blurred vision;
  • Fainting, but conscious;
  • Abnormal sensation in limbs, numbness, pins and needles;
  • Shivering and trembling of the limbs, etc.
  • Other manifestations

    Insomnia, decreased concentration, fatigue, cold hands and feet, etc.

    Complications

    Respiratory alkalosis

  • In patients with hyperventilation syndrome, respiratory alkalosis can be caused by hyperventilation of the lungs.
  • Patients may experience neurological symptoms such as dizziness, visual impairment, fainting, and convulsive behavior. Hand and foot spasms, sensory abnormalities, sweating, and muscle weakness may also occur. Severe alkalosis can present with cardiac arrhythmias and myocardial ischemia.
  • Hypocapnia

  • Hyperventilation syndrome patients can suffer from hyperventilation of the lungs, which can lead to a decrease in the concentration of plasma carbonic acid, thus causing cerebral vasoconstriction and resulting in hypoxia of brain tissue.
  • Patients may have clinical manifestations such as dizziness and blurred vision.
  • Respiratory failure

  • Patients with hyperventilation syndrome develop respiratory alkalosis, which can cause respiratory failure if not treated in time.
  • Patients may present with altered respiratory rate, rhythm and amplitude, cyanosis, tachycardia and other hypoxic symptoms. Symptoms such as agitation, confusion, and coma may also occur.
  • Renal Failure.

  • Patients with hyperventilation syndrome develop respiratory alkalosis, which can lead to renal failure if not treated promptly.
  • Patients may have little or no urine, and may also have symptoms such as loss of appetite, nausea, vomiting, dyspnea, and cardiac arrhythmias.
  • Consultation

    Department of Medicine

    Respiratory Medicine

    If symptoms such as chest tightness and dyspnea occur, it is recommended to consult the Department of Respiratory Medicine promptly.

    Emergency Department

    If you experience severe symptoms such as chest tightness, dyspnea, chest pain, palpitations, fainting, or twitching of limbs, it is recommended that you consult the Department of Emergency Medicine in a timely manner.

    Psychiatry

    If you experience symptoms such as nervousness, anxiety, fear, etc. that cannot be relieved for a long period of time, it is recommended that you consult the Department of Psychiatry in a timely manner.

    Preparation

    Preparation for consultation: registration, preparation of documents, common problems

    Tips for medical treatment

  • Take rest and relax before going to the doctor.
  • For patients with severe symptoms, it is recommended that they be accompanied by their family members.
  • Preparation List

    Symptom list

    Pay particular attention to the time of onset of symptoms, special manifestations, etc.

  • Are there symptoms such as chest tightness, dyspnea, etc.?
  • Are there symptoms such as chest pain, palpitations, etc.?
  • Are there any symptoms such as nervousness, anxiety, etc.?
  • Are there any symptoms such as dizziness, headache, fainting, etc.?
  • How long have these symptoms been present? Are there any factors that can aggravate or relieve them?
  • Medical History Checklist
  • Has there been any recent trauma, such as death of a loved one, loss of love, job loss, etc.?
  • Have you recently been overworked or stressed?
  • Have you always felt stressed recently?
  • Checklist

    Test results from the last six months, which can be brought to the doctor’s office

  • Laboratory tests: blood gas analysis, electrolyte tests.
  • Nijmegen symptomology volume.
  • Specialized tests: hyperventilation provocation test, pulmonary function tests.
  • Other tests: chest X-ray, electrocardiogram, echocardiogram, etc.
  • Diagnosis

    Diagnosis is based on

    Medical history

    The patient may have a history of mental trauma, and the onset of the disease may be preceded by overexertion, nervousness, and stress.

    Clinical manifestations

    Symptoms

    There are symptoms such as chest tightness, chest pain, palpitations, dyspnea, dizziness and headache.

    Physical signs

    The respiratory rate is accelerated and sigh-like breathing occurs.

    Laboratory Tests

    Blood gas analysis
  • Purpose: To determine whether there is an imbalance of acid-base balance in the body as well as hypoxia.
  • Significance: pH is elevated, PaCO2 is markedly decreased, PO2 is normal, and oxygen saturation is normal or slightly elevated.
  • Electrolyte test
  • Find out the serum calcium ion level.
  • Serum calcium ion levels are decreased and below 2.03 mmol/L.
  • Nijmegen Symptom Learning Volume

    A commonly used diagnostic tool, 16 common symptoms of hyperventilation syndrome are listed in this questionnaire. Points are scored according to the frequency of the symptoms, 0=never, 1=occasionally, 2=sometimes, 3=frequently, 4=frequently.

    Questionnaire content
  • Chest pain, nervousness, blurred vision, dizziness, confusion or complete inattention to surroundings.
  • Deep and rapid breathing, shortness of breath, tightness or discomfort in the chest, bloating, numbness or pins and needles in the fingers, difficulty breathing.
  • Tightness of the fingers or upper extremities, tightness around the mouth and lips, cold hands and feet, palpitations, and anxiety.
  • Analysis of results
  • A total score of 23 points or more for the 16 symptoms was used as the diagnostic criterion for symptomatology.
  • For acute episodes, the scoring method was as follows: 0 to 3 episodes/month was recorded as 1 point, 1 to 2 episodes/week as 2 points, 3 to 6 episodes/week as 3 points, and 1 or more frequent episodes per day as 4 points.
  • Hyperventilation provocation test

  • Used to determine the presence of hyperventilation.
  • Breathe hard at a rate of 60 breaths per minute and resume normal breathing after 3 minutes of continuous ventilation. If the patient’s major symptoms, especially respiratory, circulatory, and anxiety symptoms, are partially or completely induced during the hyperventilation provocation test, it is called a positive provocation test and is one of the important diagnostic criteria.
  • Diagnostic criteria

  • Typical symptoms with a total Nijmegen Symptomology Score of 23 or more on the Nijmegen Symptomology Scroll.
  • Positive hyperventilation excitation test.
  • History of trauma or overwork, stress, or psychological triggers such as stress prior to onset.
  • Fulfillment of all 3 of these conditions results in the diagnosis of classic hyperventilation syndrome; fulfillment of the third and only partial fulfillment of the first 2 results in the diagnosis of suspected hyperventilation syndrome; and none of the 3 conditions can exclude hyperventilation syndrome.

    Differential Diagnosis

    Hyperventilation syndrome needs to be differentiated from pulmonary embolism, pneumonia, interstitial fibrosis, panic disorder, and heart failure.

    Pulmonary embolism

  • Similarities: both may present with clinical manifestations such as dyspnea and chest pain.
  • Differences:
  • Patients with pulmonary embolism have elevated D-dimer on laboratory tests, thinning of lung texture and increased lung field translucency on X-ray.
  • Patients with hyperventilation syndrome can be diagnosed with the aid of blood gas analysis, hyperventilation provocation test and other tests.
  • Pneumonia

  • Similarities: both may present with symptoms such as chest tightness and chest pain.
  • Differences:
  • Patients with pneumonia often have coughing and sputum, and inflammatory lesions in the lungs can be seen on X-ray.
  • Patients with hyperventilation syndrome have normal X-rays and the diagnosis can be confirmed by hyperventilation provocation test.
  • Interstitial fibrosis

  • Similarities: both may present with dyspnea and fatigue.
  • Differences:
  • Patients with interstitial fibrosis may have “ground-glass” shadows on X-ray.
  • Patients with hyperventilation syndrome have normal X-rays and the diagnosis can be confirmed with a hyperventilation provocation test.
  • Panic disorder

  • Similarities: Both may present with palpitations, anxiety, and a sense of near death.
  • Differences:
  • The clinical presentation of patients with panic disorder is very similar to that of patients with hyperventilation syndrome and can be differentiated by a negative hyperventilation provocation test.
  • Patients with hyperventilation syndrome have a positive hyperventilation test.
  • Heart failure

  • Similarities: both may present with symptoms such as dyspnea and fatigue.
  • Differences:
  • Patients with heart failure may present with clinical manifestations such as telangiectasia and edema. ECG and echocardiography suggest myocardial damage.
  • Patients with hyperventilation syndrome have a normal ECG and a positive hyperventilation provocation test.
  • Treatment

  • Treatment aims: alleviate symptoms, control disease progression, prevent and reduce complications.
  • Treatment principle: Mild symptoms are mainly treated with abdominal breathing training, if the symptoms persistently cannot be relieved or the condition is more serious, medication and cognitive-behavioral therapy are also needed.
  • General treatment

    The main treatment is abdominal breathing training.

  • Explain to the patient the connection between the symptoms and hyperventilation, and that the symptoms are caused by hyperventilation. Relieve the patient’s mental burden and eliminate fear.
  • Patients need to learn the correct breathing method, i.e. abdominal breathing, slow breathing. Eliminate the tendency to hyperventilate by slowing down the respiratory rate or.
  • Patients need to undergo 20 sessions of breathing training, to be completed within 2 to 3 months.
  • Medication

    Benzodiazepines.

  • May be effective in reducing panic attacks.
  • Common drugs include alprazolam, diazepam, and eszopiclone.
  • Adverse effects such as drowsiness, dizziness and fatigue can occur after use. Long-term continuous use of the drug can produce dependence and addiction, withdrawal symptoms may occur when the drug is discontinued, such as agitation or depression.
  • Selective 5-hydroxytryptamine reuptake inhibitors

  • May improve symptoms such as anxiety and depression.
  • Common drugs include paroxetine and fluoxetine.
  • Paroxetine has a faster onset of action, is well tolerated, and can have adverse effects such as loss of appetite, drowsiness, insomnia, and euphoria.
  • Fluoxetine has obvious efficacy on depression and anxiety, with less side effects and good safety, adverse reactions such as palpitations, arrhythmia and chills may occur.
  • Other treatments

    The main treatment is cognitive-behavioral therapy.

  • It has been used to treat hyperventilation syndrome. Most studies have shown that relapses are less frequent after intermediate treatment.
  • Cognitive-behavioral therapy involves systematic education of the patient about the disease, followed by gradual exposure of the patient to actual scenarios that cause anxiety and learning self-control.
  • Prognosis

    Cure

  • The overall prognosis of hyperventilation syndrome is good, and it usually does not affect the natural life span of the patient.
  • After 2 to 3 months of treatment, 75% of patients experience relief of symptoms.
  • Follow-up after 1 to 2 years shows a very stable long-term outcome with a low recurrence rate.
  • Harmfulness

  • Impact on normal life: Prolonged chest tightness and breath-holding, dyspnea, palpitations, chest pain, anxiety, depression, and dizziness may affect daily life.
  • Mental health: Hyperventilation syndrome has a long course and patients are prone to depression, anxiety and other adverse emotions.
  • Daily

    Daily Management

    Dietary management

  • A light diet is recommended, avoiding stimulating foods such as chili peppers and ginger.
  • Eat more vitamin-rich foods, such as spinach and oranges.
  • Life Habits

  • Live a regular life, pay attention to rest and avoid exertion.
  • Exercise moderately and keep a good mood.
  • Follow-up

  • Importance of follow-up: Regular follow-up helps to detect recurrence and aggravation of the disease in time and adjust the treatment plan in time.
  • Follow-up time: It is recommended to follow the doctor’s instructions for follow-up.
  • Tests to be done during follow-up: Hyperventilation excitation test.
  • Prevention

    Measures to prevent hyperventilation syndrome include lifestyle changes and learning about hyperventilation syndrome.

    Lifestyle changes

  • Eat a healthy diet, take rest, exercise regularly, and avoid overexertion.
  • Learn to manage emotions and stress.
  • Reduce the intake of tea, coffee and alcoholic beverages.
  • Learn about Hyperventilation Syndrome

  • Learn about the early symptoms of hyperventilation syndrome.
  • If symptoms of hyperventilation syndrome occur, it is recommended to relax and slow down your breathing.
  • If symptoms of hyperventilation syndrome occur, it is recommended to go to the hospital as soon as possible.