Parathyroid surgery: Risks
What are the risks of parathyroid surgery?
Complications are dependent on a surgeon's experience
Complications after parathyroid surgery are rare when the surgery is performed by an experienced surgeon. Research has proven that the chance of being cured and of not having a complication after parathyroid surgery depends on the experience of the surgeon. 62 In general, a surgeon should do more than 50 parathyroid operations a year to be considered an expert. Therefore, the patient should discuss the surgeon's personal experience with parathyroid surgery and rates of complications described below. In general, the risk of complications are increased for patients having re-operative surgery (i.e. the patient has had prior thyroid, parathyroid, or other neck surgery like anterior spine fusion). 69 The three main complications that can occur after parathyroid surgery are hoarseness, low calcium levels in the blood, and bleeding in the neck.
Hoarseness (i.e. recurrent laryngeal nerve injury)
The recurrent laryngeal nerves lie on either side of the windpipe (trachea) right in the area where the parathyroid glands are found. These nerves control the vocal cords. Injury to one of the nerves may cause hoarseness or a whispering quality to the voice. Occasionally, the nerve becomes irritated while removing the parathyroid gland and causes a temporary hoarseness. In experienced hands, temporary hoarsenesss occurs in only 3 to 5% of cases and the voice typically recovers within a few days to a few weeks. However, in unusual cases, it may take up to 6 months for the voice to fully recover. Very rarely, the nerve may be cut or permanently injured. In experienced hands this occurs in less than 1% of cases.
If hoarseness does not resolve after 6 months, then the vocal cords will be examined through a direct laryngoscopy. Direct laryngoscopy is a quick, office-based procedure in which the vocal cords are examined using a camera or mirror. To help with voice recovery, speech therapy can be employed, as well as referral to a specialist. Fortunately, there are treatments that can improve and fix the voice in cases of permanent injury.
Low calcium levels in the blood (i.e. hypocalcemia or hypoparathyroidismHypoparathyroidism - When the blood calcium levels are too low because the PTH levels are too low.)
Low calcium levels in the blood can occur after parathyroidectomy because either the remaining parathyroid glands are "stunned" after the operation or too much parathyroid tissue was removed. In patients who have one or more very hyperactive glands, the remaining parathyroid glands sometimes have become much less active and need time to "wake up." In cases of subtotal or total parathyroidectomy with autotransplantationAutotransplantation - When a piece of parathyroid tissue is re-implanted in the muscle of the forearm or neck. This is usually done in cases of secondary hyperparathyroidism or re-operative parathyroid surgery., a temporary hypocalcemia is expected to occur. (see Surgical Options For Four Gland Hyperplasia) Low calcium levels in the blood can cause symptoms that include numbness or tingling in the fingertips, toes, hands, and around the mouth. In more severe cases, patients may notice involuntary twitching or cramping of muscles. In experienced hands, temporary hypocalcemia occurs in up to 5% of cases and the calcium levels typically go back to normal within a few days to a few weeks. However, in some cases, it may take up to 6 months for this temporary hypocalcemia to resolve. Very rarely, a patient may have a permanent hypocalcemia. In experienced hands, this occurs in less than 1% of cases.
If hypocalcemia occurs, the patient will require calcium supplements and potentially vitamin D pills. Vitamin D helps the body absorb more calcium from the intestines. Typically, the symptoms should get better within 30 minutes of taking the supplemental calcium. If the symptoms do not resolve with these interventions, it may be necessary to be evaluated in the clinic or an emergency room to have the blood calcium levels measured. Occasionally, in cases of very low blood calcium levels, intravenous (IV) calcium is needed to raise the blood levels. Some surgeons routinely prescribe calcium supplements after the operation to help the patient avoid having symptoms as well as to help begin the process of rebuilding bone strength. In cases of permanent hypocalcemia, the patient will require parathyroid autotransplantation if cryopreservationCryopreservation - When a piece of parathyroid tissue is frozen and stored for future use. was done or potentially will need to enroll in a trial of artificial parathyroid hormone (PTH) supplementation.
Bleeding in the neck (i.e. hematoma)
Bleeding in the neck after surgery is an extremely rare but potentially serious problem. If the hematoma increases in size, it can cause difficulty breathing. Avoidance of aspirin, blood thinners like Coumadin (warfarin), Plavix (clopidogrel), or heparin before and after surgery can reduce this risk. If a patient is on any of these medicines prior to surgery, they should be discussed with the surgeon. In addition, avoiding certain vitamin and mineral supplements, and green tea, among others herbal remedies can help to reduce the risk of bleeding. Although most hematomas occur within the first 6 hours of surgery, bleeding can happen up to a week later in patients with a bleeding disorder or who are taking blood thinners. In experienced hands, bleeding in the neck occurs in fewer than 0.5 to 1% of cases. If swelling after surgery rapidly develops in the front of the neck, the patient should immediately contact the surgical team, as it might be necessary to urgently go to the office or the emergency room for evaluation.
Infections in the neck after surgery are extremely rare and may happen only once in every 1,000 patients. For this reason, antibiotics are generally not required before or after surgery. If a fever, redness, or swelling of the wound develops, the patient should be seen by the surgical team for evaluation.