question: Why does holding your breath get rid of hiccups?
comment: Hiccups are the vagus nerve getting irritated and over stimulated by some reason (like alcohol, allergenics, etc) and then messing up movements in your diaphragm. The vagus nerve is also responsible for the autonomous coordination of your respiratory function. When you hold your breath (or hyperventilate, or drink a lot of water non stop) you are getting more CO2 in your blood, which tells the bulb (the nerve center that commands the vagus nerve) that you really should breath more. The bulb then overrides all sort of signals in the vagus nerve (such as the signals that were giving your hiccups) because it needs the diaphragm to move properly so you can get that nasty CO2 out of your bloodstream. True ELI5: imagine you are making a phone call to your grandma. Now imagine everyone in your house decides at the same time to call your grandma as well. She can't pick up all those phone calls, but she also doesn't want to let anyone fell ignored, so she rushes back and forth to try and answer everyone. Eventually, something important happens, and you yell to everyone THAT YOU REALLY NEED to speak you grandma, so everyone stops calling, and you can finally talk to her normally.
passages: Bryan R. Payne, a neurosurgeon at the Louisiana State University Health Sciences Center in New Orleans, has had some success with an experimental procedure in which a vagus nerve stimulator is implanted in the upper chest of patients with an intractable case of hiccups. "It sends rhythmic bursts of electricity to the brain by way of the vagus nerve, which passes through the neck. The Food and Drug Administration approved the vagus nerve stimulator in 1997 as a way to control seizures in some patients with epilepsy."
   A simple treatment involves increasing the partial pressure of CO and inhibiting diaphragm activity by holding one’s breath or rebreathing into a paper bag. Other potential remedies suggested by NHS Choices include pulling your knees up to your chest and leaning forward, sipping ice-cold water and swallowing some granulated sugar. 
  
  Since an orgasm results in incredible stimulation of the vagus nerve, masturbation or sex - culminating in an orgasm - can also be used as a highly effective treatment.
   The administration of intranasal vinegar was found to ease the chronic and severe hiccups of a three-year-old Japanese girl. Vinegar may stimulate the dorsal wall of the nasopharynx, where the pharyngeal branch of the glossopharyngeal nerve (the afferent of the hiccup reflex arc) is located.
   Self-induced hypocapnia through hyperventilation is the basis for the dangerous schoolyard fainting game. Deliberate hyperventilation has been used by underwater breath-hold divers for the purpose of extending dive time as it effectively reduces respiratory drive due to low levels allowing one to break one's standard limit of breath holding at the risk of shallow water blackout (which is a significant cause of drowning) as while air hunger is reduced the oxygen levels are not increased, in fact hypocapnia reduces the oxygen levels available to the brain due to the elevated affinity of oxygen to hemoglobin (Bohr effect) hence highly increasing the chances of blackout.
   Generally, there are two ways to carry out hypoventilation: at high lung volume or at low lung volume. At high lung volume, breath holdings are performed with the lungs full of air (inhalation then breath hold). Conversely, during hypoventilation at low lung volume, breath holdings are performed with the lung half full of air. To do so, one has to first exhale normally, without forcing, then hold one’s breath. This is called the exhale-hold technique.
   The breathing reflex in the human body is weakly related to the amount of oxygen in the blood but strongly related to the amount of carbon dioxide (see Hypercapnia). During apnea, the oxygen in the body is used by the cells, and excreted as carbon dioxide. Thus, the level of oxygen in the blood decreases, and the level of carbon dioxide increases. Increasing carbon dioxide levels lead to a stronger and stronger breathing reflex, up to the "breath-hold breakpoint", at which the person can no longer voluntarily hold his or her breath. This typically occurs at an arterial partial pressure of carbon dioxide of 55 mm Hg, but may differ significantly between people.
   Because the brain stem regulates breathing by monitoring the level of blood CO instead of O, hypocapnia can suppress breathing to the point of blackout from cerebral hypoxia, as exhibited in shallow water blackout.
   For the treatment of epilepsy generally the left vagus nerve is stimulated at mid-cervical region. The adverse effects of this stimulation include cardiac arrest, bradycardia, voice alteration and hoarseness, cough, shortness of breath, pain, a tingling sensation, nausea, and headache; difficulty swallowing has also been reported as common, as well as sleepiness.
  
  In randomized controlled trials for epilepsy conducted in the United States, one-third of the subjects had some type of an increase in seizures, with 17 percent having greater than a 25 percent increase, some had 100 percent increase or more.
  
  Section::::Mechanism of action.
   Lockhart stated that hiccups can sometimes be cured by pinching the skin that covers the surface of the deltoid muscles, which is supplied by the axillary nerve which shares the c5 nerve root with the phrenic nerve.
  
  Section::::Treatment.:Self-care and folk remedies.
  
  There are many superstitious and folk remedies for hiccups, including headstanding, drinking a glass of water upside-down, being frightened by someone, breathing into a bag, and eating a large spoonful of peanut butter. Placing sugar on or under the tongue has also been used.
   The partial pressure of oxygen and carbon dioxide in the arterial blood is monitored by the peripheral chemoreceptors (PNS) in the carotid artery and aortic arch. A change in the partial pressure of carbon dioxide is detected as altered pH in the cerebrospinal fluid by central chemoreceptors (CNS) in the medulla oblongata of the brainstem. Information from these sets of sensors is sent to the respiratory center which activates the effector organs – the diaphragm and other muscles of respiration. An increased level of carbon dioxide in the blood, or a decreased level of oxygen, will result in a deeper breathing pattern and increased respiratory rate to bring the blood gases back to equilibrium.
   According to the University of Texas Counseling and Mental Health Center, "Diaphragmatic breathing allows one to take normal breaths while maximizing the amount of oxygen that goes into the bloodstream. It is a way of interrupting the 'Fight or Flight' response and triggering the body's normal relaxation response." They provide a video demonstration.
  
  Section::::In complementary and alternative medicine.
  
  Some practitioners of complementary and alternative medicine believe that particular kinds of breathing they identify as diaphragm breathing can be used to bring about health benefits.
   Section::::Mechanisms of effect.:Increased breathing.
  
  The second mechanism requires hyperventilation (forced overbreathing) until symptoms of hypocapnia such as tingling, light-headedness or dizziness are felt, followed by a breath-hold. This alone is enough to cause a blackout, but it is widely believed that the effect is enhanced if lung air pressure is increased by holding the breath "hard" or "bearing down" (tightening the diaphragm as in a forced exhalation while allowing no air to escape or having an assistant apply a bear-hug). These latter actions may augment the effects of hypoxia by approximating the Valsalva maneuver, causing vagal stimulation.
   There appears to be a connection between pulmonary edema and increased pulmonary blood flow and pressure which results in capillary engorgement. This may occur during higher intensity exercise while immersed or submersed.
  
  Facial immersion at the time of initiating breath-hold is a necessary factor for maximising the mammalian diving reflex in humans.
  
  Section::::Physiological response.:Thermal balance responses.
   In Plato's "Symposium", Aristophanes has a case of the hiccups and is advised by Eryximachus, a physician, to cure them by holding his breath, or, failing that, by gargling or provoking sneezing. This ancient recommendation can be compared with the vagus nerve stimulation techniques mentioned previously.
  
  Section::::Society and culture.
  
  The word "hiccup" itself was created through imitation. The alternative spelling of "hiccough" results from the incorrect assumption that it originates from the word cough.
   Through respiratory control reflexes, any small transient fall in ventilation (A) leads to a corresponding small rise (A') in alveolar CO concentration which is sensed by the respiratory control system so that there is a subsequent small compensatory rise in ventilation (B) above its steady state level (S) that helps restore CO back to its steady state value. In general, transient or persistent disturbances in ventilation, CO or oxygen levels can be counteracted by the respiratory control system in this way.
   Section::::Applications.:Therapeutic recompression.
   VNS may also be achieved by one of the "vagal maneuvers": holding the breath for a few seconds, dipping the face in cold water, coughing, or tensing the stomach muscles as if to bear down to have a bowel movement. Patients with supraventricular tachycardia, atrial fibrillation, and other illnesses may be trained to perform vagal maneuvers (or find one or more on their own).
   The resulting arterial partial pressures of oxygen and carbon dioxide are homeostatically controlled. A rise in the arterial partial pressure of CO and, to a lesser extent, a fall in the arterial partial pressure of O, will reflexly cause deeper and faster breathing till the blood gas tensions in the lungs, and therefore the arterial blood, return to normal. The converse happens when the carbon dioxide tension falls, or, again to a lesser extent, the oxygen tension rises: the rate and depth of breathing are reduced till blood gas normality is restored.
   The respiratory centers try to maintain an arterial CO pressure of 40 mm Hg. With intentional hyperventilation, the CO content of arterial blood may be lowered to 10–20 mm Hg (the oxygen content of the blood is little affected), and the respiratory drive is diminished. This is why one can hold one's breath longer after hyperventilating than without hyperventilating. This carries the risk that unconsciousness may result before the need to breathe becomes overwhelming, which is why hyperventilation is particularly dangerous before free diving.
  
  Section::::Nitric oxide.
   In this scene, JoJo and her friend Skeebo were looking for Goliath the Lion who was hiding. With the audience's help, JoJo eventually found Goliath inside a cannon. After being reunited, JoJo realizes that Goliath had the hiccups. Skeebo then suggested that they surprise Goliath to get rid of the hiccups, and the audience was told to stand up and yell as loud as they could. When the whole audience yelled together, Goliath's hiccups disappeared. JoJo then taught everyone (including the audience) how to bow. Jamie then asked JoJo what she learned today, to which she replied, "some things are more fun if you have good friends," ending the scene. Tutter then reappeared, agreeing that it was fun when friends laughed and sang together.
   The Valsalva maneuver should be the first vagal maneuver tried and works by increasing intra-thoracic pressure and affecting baroreceptors (pressure sensors) within the arch of the aorta. It is carried out by asking the patient to hold his/her breath while trying to exhale forcibly as if straining during a bowel movement. Holding the nose and exhaling against the obstruction has a similar effect.
   The key to real core stabilization is to maintain the increased IAP while going through normal breathing cycles. […] The diaphragm then performs its breathing function at a lower position to facilitate a higher IAP.
  
  Therefore, if a person's diaphragm position is lower in general, through deep breathing, then this assists the strengthening of their core during that period. This can be an aid in strength training and other forms of athletic endeavour. For this reason, taking a deep breath or adopting a deeper breathing pattern is typically recommended when lifting heavy weights.
  
  Section::::Other animals.
   Persistent digital rectal massage has also been proven effective in terminating intractable hiccups. It is notable that an Ig Nobel Prize has been awarded for this discovery. Later in an interview the laureate Francis Fesmire explained another, probably more popular, treatment for hiccups: "An orgasm results in incredible stimulation of the vagus nerve. From now on, I will be recommending sex – culminating with orgasm – as the cure-all for intractable hiccups." 
   Pressing is a form of torture or execution that works through asphyxia e.g. burking.
  
  Section::::Cause.:Perinatal asphyxia.
   BULLET::::- Side effects
  
  Temporary paresis (impairment of the function) of the thoracic diaphragm occurs in virtually all people who have undergone interscalene or supraclavicular brachial plexus block. Significant respiratory impairment can be demonstrated in these people by pulmonary function testing. In certain people — such as those with severe chronic obstructive pulmonary disease — this can result in respiratory failure requiring tracheal intubation and mechanical ventilation until the block dissipates.
  