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What is venesection

Taking blood – called venesection or phlebotomy in medical language – reduces red blood cell counts in people with polycythaemia vera (PV). It has very few risks.

If you have polycythaemia vera (PV) you have too many red blood cells. One way to reduce your red cell count that does not require any medication at all is to use a procedure called venesection or phlebotomy.

It’s a simple procedure done just like having a blood draw or making a blood donation – a doctor or nurse inserts a needle into your vein and collects some blood. Patients with PV usually have about anywhere from 350 ml to 500 ml of blood removed during venesection. The amount depends on your height and weight as well as your haematocrit, (blood thickness or packed cell volume level) and your general state of health.

How it works

Phlebotomy (or venesection) is a standard treatment for PV and helps bring your red cell count closer to normal. Your haematologist will ask you to come to hospital to have some blood removed. It works in the short-term since you make up the liquid part of your blood (plasma) quicker than red cells and in the long-term iron stores are reduced slowing down the production of red cells. For this reason it is very important not to take iron if you are a patient with PV.

You may need regular venesections every few weeks or months until you reach an acceptable blood thickness level. Your target blood thickness (haematocrit) depends on your risk factors, how well you tolerate the procedure and whether you’ve had any previous complications such as a blood clot.

Why try this treatment

Phlebotomy has some real advantages for people with PV:

  • It works quickly
  • It doesn’t require any medications
  • It has minimal side effects
  • It is effective at reducing red cell counts (and thus risks)

With regular venesections, your haematocrit (or packed cell volume) can reach a normal level, allowing your heart to pump blood more efficiently. However phlebotomy does not reduce white cells or platelet levels.

Together with medication

You may need low dose aspirin therapy and/or a cytoreductive treatment such as hydroxycarbamide (Hydroxyurea), interferon or anagrelide in addition to regular phlebotomies. Your haematologist will work with you to find the best combination for your individual condition.

Common side effects

You may feel tired after giving blood, and you may have some local soreness or bruising, but serious side effects are very uncommon. Some people faint after giving blood, if you feel dizzy or unwell in the 24 hours afterwards tell your team and they may give you some fluid (salt water) to replace the volume lost in the blood. This is more likely to happen if you are taking tablets for blood pressure and if you have not eaten before attending the hospital.

Tips for Coping with Venesection

Day prior to venesection: Drink plenty of fluids the day before to stay hydrated.

Are you hydrated:

  • Very pale yellow to clear urine – well hydrated
  • Pale yellow urine – somewhat dehydrated – drink a glass of water
  • Pale honey urine – dehydrated – drink 2-3 glass of water
  • Bright yellow – very dehydrated – drink a large bottle of water,

12 hours prior: Eat something salty in the 12 hours before. You lose about 3 grams of salt with each donation

3 hours prior:

  • Drink 3 large glasses of water or juice
  • Eat something. Go for savoury and salty foods

In the 2 hours following, avoid smoking

In the 6 hours following:

  • drink at least 3 good size glasses of juice or water
  • avoid strenuous exercise
  • don’t stand for long periods
  • try not overheat (avoid hot showers, being in the sun, hot drinks)

In the 8 hours following, avoid alcohol.

These are some other tips for coping with phlebotomy shared by people with PV.

  • Take it easy Plan a restful time after your venesection. You may feel a bit tired so you don’t want to schedule too much.
  • Let others know Tell family members and others you trust that you are having a venesection so you may need a little extra help, for instance if you are caring for young children.
  • Arrange transport You may be too tired to drive or travel by public transport right after a venesection, in particular if you are feeling fatigued for other reasons, for instance as a side effect of your MPN.
  • For women It is best (although not essential) to schedule venesections for a time of the month when you are not menstruating. This will prevent you from feeling excessively tired after venesection.

Venesection FAQs

Can I eat and drink normally?

Yes. We recommend that you eat a normal, healthy diet and drink plenty of water.

Can I drink alcohol?

While it is usually safe to drink alcohol in moderation, Australian NHMRC guidelines state that for healthy women and men drinking no more than two standard drinks on any day reduces your risk of harm from alcohol-related disease. Alcohol can cause dehydration and it is important to avoid becoming dehydrated if you have an MPN. You are advised to discuss any alcohol consumption with your doctor.

What if I want to have a child?

Venesection or removal of blood is a safe treatment if you are pregnant or planning to father a child. If you are pregnant, you may need fewer phlebotomies during your pregnancy. Please see our pregnancy section for more information on pregnancy in MPNs.

Who will do my venesection?

Your doctor or a specially trained nurse will take blood. Your haematologist will give you instructions about where to obtain this service. The Australian Red Cross in many cases is able to do the venesections for you.  Your GP is required to complete the form to submit to the Red Cross.

Can I drive?

You may feel faint or fatigued after venesection. If you are feeling drowsy or fatigued for any reason do not drive.

Do I need to take any special precautions?

Please make the nurse performing your venesections aware if you have any of the following conditions or are taking any of these medications:

  • If you are taking warfarin.
  • If you are taking beta-blockers (drugs which control blood pressure).
  • If you weigh less than 49kg.
  • If you have previously fainted or felt unwell after a blood test or venesection.
  • If you are frightened of needles.
  • If you have a serious heart condition.

If any of the above applies to you, your medical team may need to take special precautions to ensure that venesection can be carried out safely.

What can I do to help myself?

If you have an MPN, it’s important to take good care of yourself. There are many things you can do to feel better.

  • Good nutrition is important. Eat a balanced diet including lots of fresh fruit and vegetables, lean protein and whole grains.
  • Drink plenty of water and prevent dehydration by avoiding excessive alcohol and caffeinated drinks.
  • Maintain a normal weight and maintain your muscle mass to help keep your cholesterol and blood sugar within normal limits.
  • Exercise is very beneficial for people with MPNs and helps to fight fatigue. Before starting on any new programme, check with your GP or haematologist and start slowly and gently.
  • Stop smoking. Ask your GP if you need help.
  • Consider wellness activities such as yoga, aerobic activity, strength training, meditation, massages, support groups, improved nutrition etc – an international study of hundreds of MPN patients showed wellness activities had a pattern of decreased levels of symptom burden, fatigue, depression, and a higher quality of life for MPN patients. (Survey of integrative medicine in myeloproliferative neoplasms – the SIMM study).

More information on living well with an MPN is available at www.mpnallianceaustralia.org.au.

General advice

This is intended as general information about venesections. It is important that in addition to this information, you discuss any concerns with your general practitioner or haematologist.

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