What is venesection (phlebotomy)?

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From the Guidelines

Venesection, also known as phlebotomy, is a medical procedure that involves removing blood from a patient's vein to treat conditions like hemochromatosis or polycythemia vera, with the goal of reducing iron overload or excess red blood cells. The procedure is commonly performed by inserting a needle into a vein, usually in the arm, and withdrawing a specific amount of blood, typically 400-500ml per session, as recommended by the EASL clinical practice guidelines on haemochromatosis 1. The frequency of phlebotomy varies from weekly to every few months, depending on the condition being treated and the patient's response, with the target serum ferritin level ranging from 50-100 lg/L during the maintenance phase, as suggested by the American College of Gastroenterology and other expert groups 1. Some key points to consider when performing venesection include:

  • Monitoring serum ferritin levels to ensure the target value is achieved and maintained, and to avoid overtreatment or iron deficiency 1
  • Measuring serum haemoglobin levels before each phlebotomy session to avoid reducing the haematocrit or haemoglobin to unsafe levels 1
  • Adjusting the frequency and volume of phlebotomies based on the patient's iron status and response to treatment, with the goal of preventing complications like organ damage or blood clots 1
  • Considering the potential risks and benefits of venesection, including the risk of iron deficiency or anaemia, and the benefits of reducing iron overload or excess red blood cells 1. Overall, venesection is a safe and effective treatment for conditions like hemochromatosis or polycythemia vera, when performed properly and with careful monitoring of the patient's response.

From the Research

Definition of Venesection

  • Venesection, also known as phlebotomy, is a medical procedure that involves the removal of blood from the body, typically to reduce the amount of iron in the blood [ 2 ].
  • This procedure is often used to treat conditions such as hereditary hemochromatosis, where the body absorbs too much iron from food [ 3 ].

Purpose of Venesection

  • The primary purpose of venesection is to remove excess iron from the body, which can help to prevent damage to organs such as the liver, heart, and pancreas [ 4 ].
  • Venesection can also be used to reduce the risk of complications associated with iron overload, such as cardiac and liver damage [ 3 ].

Procedure and Frequency

  • The procedure typically involves the removal of a certain amount of blood from a vein in the arm, usually on a regular basis, such as weekly or monthly [ 2 ].
  • The frequency and amount of blood removed during venesection can vary depending on the individual's condition and the severity of their iron overload [ 5 ].
  • In some cases, venesection may be used in combination with other treatments, such as iron chelation therapy, to help manage iron overload [ 5 ].

Monitoring and Guidance

  • The effectiveness of venesection can be monitored using various laboratory tests, including measurements of hemoglobin, mean corpuscular volume (MCV), and transferrin saturation [ 6 ].
  • The MCV can be used as a guide to determine the pace of phlebotomy therapy, with the goal of maintaining the MCV at a certain level to ensure adequate iron availability for erythropoiesis [ 6 ].

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Chelation therapy for iron overload.

Current gastroenterology reports, 2007

Research

Iron mobilization using chelation and phlebotomy.

Journal of trace elements in medicine and biology : organ of the Society for Minerals and Trace Elements (GMS), 2012

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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