Hiccups can sometimes be amusing especially in children because they're totally involuntary and they produce a strange sound. Hiccups are caused when the diaphragm starts contracting involuntarily. The diaphragm is the layer of muscle found at the bottom of the lungs. It separates the abdominal region of the body from the thoracic cavity. This muscle plays an invaluable role in the mechanism of breathing. As it contracts, the volume of the thoracic cavity increases so that the lungs can inflate with air.

Why Do I Have Hiccups After Surgery? 

During surgical procedures, it's required to administer anesthetic drugs so that the patient feels no pain during the surgery. These general anesthetic drugs cause an irritation on the vagus nerve which works the diaphragm. The irritation translates to hiccups in the post-operative patient. This effect is not limited to general anesthesia, but can also occur in cases of local anesthesia that affects a large part of the body, such as spinal anesthesia or epidural anesthesia. 

Hiccups that are triggered by anesthesia drugs are usually chronic spasms. Normal hiccups can last from a few minutes up to a few hours. However, chronic hiccups can last for over 48 hours, or in some cases longer than a month. When the diaphragm contracts suddenly, you breathe in air quickly but opening to your vocal chords closes quickly as well. This creates the distinctive noise of a hiccup. 

Other Possible Causes of Hiccups

Apart from hiccups caused by anesthesia, other conditions can also lead to hiccups. If your hiccups are temporary, they may be triggered by:

• Certain emotional feelings, like excitement, fear or stress
• Smoking which causes too much air to be swallowed
• Alcohol
• Having a gassy tummy
• Some spicy foods which may irritate the diaphragm
• Eating too fast
• Fizzy drinks
• Hot beverages
• Sudden change in ambient temperature
• An abrupt change in temperature in your body, like eating something hot followed by a very cold beverage

If you have long-term hiccups after surgery, they can also be the results of: 

• Intestinal problems, like gastro-esophageal reflux disease (GORD), small intestine obstruction, inflammatory bowel disease (IBD)
• Certain breathing disorders, like pleurisy, pneumonia or asthma
• Any medical condition that affects the vagus nerve, like meningitis, goiter, pharyngitis, strokes and brain tumors
• Liver swelling or infections can also irritate the diaphragm.
• Metabolic disorders, like hyper- and hypo-glycaemia and diabetes

There are other medicines that can also trigger hiccups by causing acid reflux. Some of them are:

• Chemotherapy medications
• Hypertension medication called methyldopa (Aldomet®)
• Prescription pain medicines called opioids
• Sedatives called barbiturates
• Anxiety medicines called benzodiazepines, like diazepam, alprazolam and lorazepam
• Anti-inflammatories called corticosteroids

How to Manage Hiccups After Surgery

Hiccups usually stop on their own. They require no medical intervention in the form of medicines or other treatments. But if your hiccups are really serious and interrupting your daily life, you may try the following treatment options. 

1. Home Remedies

A few home remedies are said to resolve hiccups according to folklore:

• Bite into a lemon, take a sip of vinegar, sip very cold water or take some granulated sugar. These all involve stimulating the nasopharynx.
• Hold your breath for a few seconds, sneeze or breathe into a paper bag. These maneuvers all involve changing the normal breathing cycle.
• Laugh out loudly while watching your favorite comedy seems to be the most enjoyable method.
• Singing loudly is also believed to stop hiccups because you control your breathing unconsciously.
• Pull the knees up to the chest or compress the chest by leaning forward. These all serve to counter-irritate the diaphragm.
• A small piece of ginger, peeled and cleaned, should be chewed on slowly to ease your hiccups.
• Eating a spoonful of peanut butter is especially useful for children that won't tolerate the other home remedies.
• Boil cardamom powder in water, then strain and drink when it cools down. It is believed to relax the diaphragm, thus stopping the hiccups. One teaspoon of cardamom powder needs 375ml of water.
• Acupuncture or hypnotherapy show some promise in relieving hiccups.

2. Electrical Stimulation

Medical intervention techniques can be used, like electrical stimulation of the vagus nerve, radio-frequency stimulation of the vagus nerve with ultrasound, and in some rare cases, trans-esophageal diaphragmatic pacing.

3. Medications

Drug intervention to treat hiccups after surgery include:

• Chlorpromazine (most commonly used)
• Haloperidol
• Some anti-convulsant medications to control the spasms in the diaphragm, including phenytoin, sodium valproate, carbamazepine and gabapentin. However, phenytoin has been known to have hiccups as an adverse effect.
• Metoclopramide is used especially if the cause of the hiccups is gastric in nature, like distension of the stomach or bowels or if the cause is gastric stasis.
• Baclofen has been used with success but should be used with care in the elderly.
• Amitriptyline, dexamethasone and nifedipine have also been used successfully.
• In cancer patients with severe hiccups, ketamine, midazolam or lidocaine administered intravenously have been used with positive results.

4. Surgical Intervention

Interrupting the vagus nerve surgically is the last resort that doctors will use because of the risk of this type of surgery. Micro-vascular decompression is sometimes attempted when all other therapies have failed.