Parathyroidectomy. Removal of the Parathyroid Glands of the Neck due to Renal Hyperparathyroidism. Produced by the Renal Directorate

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1 Parathyroidectomy Removal of the Parathyroid Glands of the Neck due to Renal Hyperparathyroidism Produced by the Renal Directorate Produced: January 2008 Reviewed: May 2012 Review date: January 2014

2 What is a parathyroidectomy? A parathyroidectomy is an operation performed to remove parathyroid glands that are producing too much parathyroid hormone (PTH). The parathyroid glands are small glands usually situated behind the thyroid gland at the base of the neck. They produce PTH, which controls the level of calcium in the blood. Good control of blood calcium levels is important for the proper functioning of the brain and nervous tissue and the maintenance of healthy bones. Why is a parathyroidectomy performed? In some patients with kidney disease, a complex sequence of events can cause the parathyroid glands to become overactive and produce too much parathyroid hormone. This leads to high calcium levels in the blood and over a period of time this can cause damage to the bones, blood vessels and heart. The sequence of events is known as renal hyperparathyroidism (RHPT). Why do I need a parathyroidectomy? There are normally four parathyroid glands, each one the size of a pinhead (0.1cm), usually situated close to the thyroid gland. Their function is completely unrelated to that of the thyroid. In people with kidney failure requiring a parathyroidectomy the parathyroid glands are enlarged sometimes to the size of a small pea (0.5cm). The operation is intended to cure or reduce symptoms that are caused by the RHPT. The renal physician will discuss the reasons why you have been referred for this surgery and the expectation of improvement in your symptoms. The procedure and the risks involved will be explained to you when you see the surgeon. 2

3 What tests are needed before the operation? You will have already had a number of blood tests to measure the PTH level, to confirm that your PTH level is high and there is a need for the operation. The surgeons also ask for two scans of the parathyroid glands as their position can be variable and the scans will help them to locate the glands. One of the scans normally requested is a radio-isotope (nuclear) scan for which you will attend the Nuclear Medicine Department at the Royal Preston Hospital where the scan can take up to 5 hours. The second scan is an ultrasound scan of the neck which will be performed in the X-ray department either at the Royal Preston Hospital or your local hospital. Also prior to your operation an ear, nose and throat surgeon will perform an examination of your vocal cords. This involves the surgeon looking at the back of the throat with a mirror or a flexible telescopic instrument without a general anaesthetic. You may be given an infusion of a drug called methylthioninium chloride (methylene blue) just before you go to theatre. This stains the parathyroid gland and helps the surgeon to locate the glands during the operation. Common side effects include headache, nausea and vomiting. Following the infusion your skin, urine, saliva and stools may temporarily turn a blue / green colour, this usually resolves within 24 hours, let the doctor or nurse looking after you know if you experience any side effects as you may need painkillers or anti-sickness medication. How long does the operation take? The operation is performed under a general anaesthetic. The operation takes up to 2 hours. The surgeon needs to make a cut in the skin about 10cm (4 inches) long. This is made in one of the skin folds in the lower neck. The scar normally heals very well. Although the scar is in an area that is clearly visible the scar itself becomes virtually invisible and most patients who have had the operation do not find the scar causes them any problem or embarrassment. Recovery from the operation is usually fast, with people being out of bed the next day and walking about the day after. How long will I stay in hospital? Following the operation you will need frequent blood tests to monitor the level of calcium in your blood, as it is normal for the level to be low after the operation. You will be required to take oral calcium supplements, usually in tablet form, to raise the calcium levels in your blood. If your calcium level falls very low you may need intravenous calcium as a drip into a vein via a small cannula or tube. To allow the doctors to stabilise your calcium levels you therefore need to be in hospital for about 5 days. Are there any tablets that I should stop taking before admission for my parathyroidectomy? You should usually continue all your tablets and bring them with you to hospital. 3

4 If you are taking Aspirin you should stop taking this 7 days before your operation. If you are taking Clopidogrel you should stop taking this 10 days before your operation. If you are taking warfarin, arrangements for stopping this should be discussed with your Consultant before your operation. What are the complications of a parathyroidectomy? As with any operation, there are possible complications. Your surgeon or a member of the surgical team should discuss these with you before the operation. Complications of any operation Any general anaesthetic or surgical operation carries risks such as infection or bleeding. These risks vary from person to person. For someone who is young and fit even if they have kidney problems the risk is very small. However if someone is older with a history of heart or chest problems there is a greater risk of complications or death. It is advisable to discuss with your doctor/consultant about risks in your case. Bleeding in the first couple of hours after surgery Surgeons take great care to make sure there is no bleeding at the end of an operation on the neck. However, bleeding can occur. If excessive bleeding has occurred, a large bruise could develop and could compress the windpipe, making it difficult to breathe. In the unlikely event of this happening a tracheostomy would be required. This is a surgical procedure to create an opening into the windpipe (trachea) to enable you to breathe more effectively. For this reason, the cut is normally closed with metal clips, which are easier to remove than stitches if there is bleeding. Fortunately excessive bleeding is exceptionally rare (less than 1 in 100 operations), and there is a very careful watch kept on all parathyroidectomy patients for several hours after the operation. Will it affect my voice? The parathyroid glands lie close to the voice box (larynx) and the nerves to the voice box. Following your surgery you may find that your voice may sound hoarse and weak and your singing voice may be slightly altered, but this generally recovers quite quickly. In a very small number of cases this can be permanent (about 1 in 500 cases). Low calcium levels When excess PTH is suddenly removed from the blood stream, blood calcium levels can fall. This can be especially severe in people with kidney disease where the bones have been starved of calcium by the high levels of PTH. Following a parathyroidectomy your bones can soak up large amounts of calcium. Very low blood calcium levels can cause pins and needles or muscle spasms. It is usually necessary to give large numbers of calcium tablets after a parathyroidectomy and sometimes to give calcium through a drip into a vein. Failure of surgery to reduce calcium and PTH levels adequately Sometimes the operation does not work completely. This may be because there are more parathyroid glands than expected, or one is in an unusual place (even the upper chest), or because a gland in its normal position is missed. These problems can occur with the most careful and expert of surgeons. It is therefore possible you would need further blood tests, a scan and possibly surgery. 4

5 What treatment is needed afterwards? Most people with kidney disease who have had parathyroidectomy have to take calcium and vitamin D tablets for some time after the operation. This is because bones will be replacing the calcium they have lost during the time that parathyroid glands have been overactive. You will be required to have frequent blood tests so that the calcium levels in your blood can be monitored. Initially you will probably need to take a large number of tablets to control your calcium levels. It is therefore sensible not to plan a holiday or go abroad for a few weeks after the operation. However over time as your bones soak up the calcium, this number will reduce. Long term monitoring of calcium, phosphate and PTH is always necessary, even after successful surgery. You should be given an early outpatient appointment upon discharge from hospital. If you do not receive this please contact the Dialysis Adequacy Practitioner Can the parathyroid glands enlarge again after surgery? In people with kidney failure even after a parathyroidectomy glands are under constant stimulation and regrowth can occur. Even when the surgeon knows all visible parathyroid tissue has been removed, there is a chance that many years later a gland will appear and more surgery will be needed. It is important that calcium and phosphate levels are controlled to help prevent excess production of PTH. What are the benefits of having a parathyroidectomy? A parathyroidectomy is usually a very effective operation; it is intended to cure or reduce the symptoms that are caused by the RHPT with medication alone. It returns calcium and parathyroid hormone levels to normal and therefore prevents the complications associated with abnormal levels. Following a parathyroidectomy patients generally enjoy an improved quality of life due to a reduction in the symptoms they had prior to their operation. What is the alternative? The doctor has recommended a parathyroidectomy to treat your RHPT. If you decide against having this operation an alternative would be to continue on your current medication. Unfortunately it is often extremely difficult to treat RHPT with medication alone. A parathyroidectomy would be recommended to you at this point. However if you decide against this your bones will become progressively weaker, your risk of fractures would increase considerably and high calcium levels would continue to harm your blood vessels and heart. Another way to treat RHPT is with a medication called Cinacalcet. Cinacalcet is not generally recommended to treat RHPT due to kidney disease. The National Institute for Health and Clinical Excellence (NICE) reviewed this treatment and provided guidance about it s use. NICE produces guidance to the NHS about preventing, diagnosing and treating different medical conditions. It found that there was not enough reliable evidence to show that Cinacalcet was more effective than existing treatments. It is therefore only used in people, who due to their poor health cannot have a parathyroidectomy because of the risks involved. There is more information available on the NICE website, 5

6 Sources of further information: If you require further information please contact the Dialysis Adequacy Practitioner on the Dialysis Unit at Royal Preston Hospital Lancashire Teaching Hospitals NHS Foundation Trust is not responsible for the content of external internet sites.