Knowing these two major functions of calcium helps explain why people can get a tingling sensation in their fingers or cramps in the muscles of their hands when calcium levels drop below normal. A sudden drop in the calcium level (which can occur following a thyroid surgery) can cause patients to feel "foggy", "weird" or "confused like my brain isn't working correctly". The brain DEMANDS a normal steady-state calcium level, so any change in the
amount of calcium can cause the brain to feel un-loved and the patient to feel bad. Low calcium levels after thyroid surgery are also commonly associated with symptoms of tingling around the lips, hands, and/or feet. Cramping, facial twitching, or muscular spasms can also occur and may be more serious if not promptly treated. Although the four parathyroid glands are quite small, they have a very rich blood supply. This
suits them well since they are required to monitor the calcium level in the blood 24 hours a day. As the blood filters through the parathyroid glands, they detect the amount of calcium present in the blood and react by making more or less parathyroid hormone (PTH). When the calcium level in the blood is too low, the cells of the parathyroids sense it and make more parathyroid hormone. Once the parathyroid hormone is released into the blood, it circulates to act in a number of places to increase
the amount of calcium in the blood (like removing calcium from bones). When the calcium level in the blood is too high, the cells of the parathyroids make less parathyroid hormone (or stop making it altogether), thereby allowing calcium levels to decrease. This feed-back mechanism runs constantly, thereby maintaining calcium (and parathyroid hormone) in a very narrow "normal" range. In a normal person with normal parathyroid glands, their parathyroid glands will turn on and off dozens of times
per day...in an attempt to keep the calcium level in the normal range so our brain and muscles function properly. Normal parathyroid function maintains nearly constant calcium levels... with almost zero variability. If the normal parathyroid glands are severely damaged or removed, they will not produce parathyroid hormone and calcium levels will drop. They can drop rapidly and place patients at serious risk of low calcium complications. Normal parathyroid glands
have quite predictable locations. When they are not in those predictable locations, we also know where they are most commonly located. Most normal parathyroid glands are quite tiny in the 4-6 mm range. Even though we already told you that parathyroid glands have a rich blood supply, the parathyroid glands don’t like it very much when we touch them during the thyroid surgery or have to move them out of the way. The superior parathyroid glands are quite commonly tucked underneath the
superior pole (upper part) of the thyroid and quite intimately attached to the capsule of the thyroid gland. The inferior parathyroid glands are at greatest risk in thyroid cancer surgery when the lymph nodes of the central compartment are being removed. Parathyroid glands that are immediately adjacent to clearly cancerous lymph nodes should never be transplanted in thyroid cancer surgery. Parathyroid glands that don’t look healthy (they start looking brownish from decreased blood flow) following thyroidectomy or central compartment neck dissection should be transplanted whenever feasible. Any tissue that is being removed in thyroid cancer surgery should be closely examined for parathyroid tissue before it is sent to the pathologist for final analysis. Once tissue has left the operating room, it cannot be transplanted back into the patient! Immediately following completion of your thyroid cancer surgery, the blood level of your parathyroid hormone produced by these glands can be measured to verify that your parathyroid gland (s) are meeting your body’s calcium regulation needs. You actually don’t need all of your parathyroid glands. In fact, most individuals can function totally normally with just one normal functioning parathyroid gland. But every one of your parathyroid glands should be managed as your only functioning gland. Each one of these parathyroid glands is critically important especially in thyroid cancer patients. Become Our PatientFounded by Dr Gary Clayman, the Clayman Thyroid Center is widely known as America’s leading thyroid surgery center performing nearly 2000 thyroid operations annually. Our reputation as the best thyroid surgeons means patients from all over the US and many foreign countries travel to Tampa for their thyroid surgery. With same-day evaluation and surgery scheduling, we make traveling for thyroid surgery convenient for every patient. Become Our Patient Here BACKGROUND The most common cause of hypoparathyroidism is damage to the glands during thyroid surgery. There are usually 4 parathyroid glands in the neck and they located next to the thyroid, with 2 glands on each side. These glands frequently get bruised during surgery and mild hypoparathyroidism is rather common after surgery but usually resolves after a few days to weeks. While rare, permanent hypoparathyroidism continues to be a real, clinical problem after thyroid surgery. If it appears that the parathyroid gland(s) will not be able to recover, surgeons may autotransplant one or more parathyroid glands into the muscles of the neck during surgery. However, there remains considerable controversy and uncertainty among surgeons as to the best approach to reduce the risk of hypoparathyroidism when performing thyroidectomy. In the hands of an experienced surgeon that does a lot of thyroid surgeries (high volume thyroid surgeon), the risk of permanent hypoparathyroidism should be <5%. The incidence in children is higher than in adults, possibly related to the decreased incidence of thyroid surgery and therefore decreased experience among many pediatric thyroid surgeons. However, even in experienced surgical hands in adult patients, the risk of temporary hypoparathyroidism is high. Only a few studies have tried to report the risks of hypoparathyroidism. The first paper reports on post-surgical hypoparathyroidism in children, while the second paper focuses on adults. THE FULL ARTICLE TITLE: Gschwandtner E et al Hermann M 2018 How many parathyroid glands can be identified during thyroidectomy? Evidence-based data for medical experts. Eur Surg 50:14–21. Epub 2017 Dec 13. PMID: 29445392. SUMMARY OF THE STUDY In the second study, 350 adult patients > 18 years of age had a near-total, subtotal, or total thyroidectomy over an 8 year period by a single surgeon, mainly for benign disease (only 14% were for Graves’ disease). Almost 1/3 of patients developed temporary hypoparathyroidism, but only 4% had permanent hypoparathyroidism, all but one of which was not severe. An average of 2.28 parathyroid glands were identified by the surgeon at the time of thyroid surgery. No parathyroid glands were found in 20 patients, 1 in 16 patients, 2 in 126 patients, 3 in 114 patients, and 4 in 41 patients. Central node dissection for cancer and parathyroid autotransplantation increased the risk of temporary and permanent hypoparathyroidism. WHAT ARE THE IMPLICATIONS OF THIS STUDY? — Melanie Goldfarb, MD What happens if you remove all parathyroid glands?Only one half functioning parathyroid gland is needed for calcium control. If all four parathyroid glands were injured or removed during surgery, the blood calcium levels can become lower than normal.
Can you live without the parathyroid gland?Parathyroid glands control the amount of calcium in your blood. Parathyroid glands control the amount of calcium in your bones. You can easily live with one (or even 1/2) parathyroid gland. Removing all 4 parathyroid glands will cause very bad symptoms of too little calcium (hypOparathyroidism).
What does the absence of parathyroid hormone cause?Hypoparathyroidism is a rare endocrine disorder characterized by absent or inappropriately low concentrations of circulating parathyroid hormone (PTH), which leads to hypocalcemia, hyperphosphatemia and increased fractional excretion of calcium in the urine.
Does removal of parathyroid cause weight gain?Weight Gain Caused by Parathyroid Surgery: A Myth? There is no physiologic mechanism for parathyroid surgery to cause weight gain. There is no reason that removing a parathyroid tumor and re-establishing normal body hormone and calcium levels would cause weight gain.
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