New Guideline about anaemia in perioperative patients

Professor Scarlett McNally

CPOC Deputy Director 

An important new guideline about anaemia in people having surgery aims to change how healthcare is delivered. Anaemia means having a low Haemoglobin (Hb) which reduces the oxygen carrying capacity of blood. It is very common and simple interventions for the anaemia or its confounding conditions can be effective. The biology of anaemia is complex. This new guideline liberates knowledge and provides a clear structure for every member of healthcare staff.

The new guideline is the work of the Centre for Perioperative Care (CPOC), a partnership between ten major organisations of healthcare professionals. CPOC was born out of frustration at the inefficiencies, duplications and missed opportunities that occur too often in the care of people having operations. CPOC’s anaemia writing group included representatives from over 20 organisations alongside patients, lay members, healthcare staff and doctors in postgraduate training. An extensive literature review was undertaken to create algorithms and standardised pathways and to provide a solid evidence base for the recommendations. The recommendations are for patients, healthcare staff in different areas and for managers organising services.

This is not just another set of standards requiring hard-working NHS staff to achieve impossible targets in an overwhelmed system. It incorporates existing excellent guidelines that are not readily used because they tend to be specialty-specific.

One third of people having major surgery are anaemic before the operation. This is often diagnosed late. The blood loss of surgery or trauma can cause or worsen anaemia. People with anaemia are two to three times more likely to have a major complication after surgery (including poorer wound healing, slower mobilisation and an increased risk of death). Anaemia is responsible for around 20% of the difference in outcomes, with most resulting from the co-existing conditions.

The fundamental issue is that anaemia is not merely an abnormal laboratory value to be documented, but part of a person’s wider health and optimising anaemia can be effective.

The biology of anaemia is complex. Algorithms and explanations in this new guideline allow all staff to understand the types of anaemia, the rationale for testing and how to advise on simple optimisation (eg diet) that can improve recovery and future life. A generalised pathway including testing is recommended and care should then be individualised, especially when test results are available.

The commonest cause of anaemia is low iron (‘iron deficiency’). The guideline explains how to establish the type and cause of anaemia. Types include: iron deficiency, functional iron deficiency from long-term conditions such as kidney disease, B12 or folate deficiency or a genetic cause. Iron deficiency is usually from: excess blood loss from menstruation or other bleeding; insufficient intake in the diet; poor absorption in the gut (such as with coeliac disease); or a combination of these factors. The British Society of Gastroenterology welcomes referral of men and post-menopausal women with iron deficiency anaemia for investigation since one-third are found to have a gastrointestinal cause, for example a bowel cancer. B12 deficiency is very common, affecting 20% of the UK population over the age of 65 and is increasingly recognised as a problem resulting from plant-based diets.

The guideline encourages a Patient Blood Management (PBM) approach. This has three pillars – assessing and managing anaemia, reducing blood loss and maximising the patient’s physiological tolerance of anaemia. Intervention studies show that a PBM approach leads to reduced blood transfusion, length of stay, complications and hospital costs. Standardised pathways across the whole perioperative journey should anticipate problems. Anaemia should be diagnosed early and its cause investigated, treatment should be given, intra-operative blood loss minimised and the patient’s physiological response optimised. Where abnormalities are detected, an individualised Shared Decision Making (SDM) discussion should occur between a senior clinician and the patient. SDM involves balancing risks of delaying surgery and the different options for treating anaemia and optimisation. SDM includes considering Benefits, Risks, Alternatives and what happens if Nothing is done, with the acronym ‘BRAN’. Half the patients undergoing surgery that requires an anaesthetist are over the age of 65, an age when half the population have multiple co-morbidities, so individualisation is needed. Intravenous iron can be useful in selected patients. Blood transfusion itself carries risks, particularly affecting immunity and exposure to multiple donors. Even in emergency patients where preparation time is limited, Tranexamic acid is recommended to reduce blood loss in surgery.

Patients were heavily involved and CPOC insists that patients should not be passive. For example, doses of oral iron should not be taken too frequently as this leads to feedback with Herceptin reducing how much iron is absorbed.

CPOC has already written cross-organisational guidance on Diabetes, Frailty, Day surgery and optimisation for people undergoing surgery. There are seven types of intervention that help optimise patients for surgery. These are: nutrition, exercise, smoking cessation, medication review, psychological input and empowerment, alcohol moderation and preparation for post-operative practicalities. These reduce complications by 1/3 to ½, reduce length of stay and increase day surgery rates. These impacts on patient flow could be useful in a time of lengthy waiting lists and a shortage of NHS beds. Specifically in anaemia, people who are fitter can withstand the impact of anaemia better.

The guideline covers all ages from neonates to elderly patients who may be undergoing surgery for hip fracture or emergency abdominal surgery. Anaemia in pregnancy is included because 31% of babies are delivered by Caesarean section in the UK, of which 56% are as an emergency, 12% of births have an instrumental delivery and 30% are anaemic after birth.

Standards listed in the guideline include: use of pathways, early diagnosis of anaemia including in children, testing for type and cause of anaemia and deciding on clear plans for management; patient information should be available; education for all staff and collection of data and auditing are to be monitored.

The CPOC approach is a radical demand for better care. It acknowledges the different way that people think, work and act. General pathways with clear algorithms can be followed by all staff, including non-registered staff and managers. The waiting list should be a preparation list including optimisation for surgery. Patients should not be passive and need good information. The pathway should identify points where individualisation with a senior clinician is required. This approach values and empowers each member of the team with knowledge and skills backed up by multiple specialty-specific guidelines and a vast literature. It provides a clear grounding of knowledge whilst acknowledging controversies, such as whether the decades-old sex difference in definition of anaemia is misogynistic, expecting menstruating women to live with a Hb of 120mg/L, whereas they may be healthier with 130 mg/L.

The seven types of optimisation are the same interventions as improve health in general and reduce health inequalities. If we can get this right for these complex patients undergoing major surgery, we can get it right for future health.

The NHS workforce is under huge pressure. Previous guidelines were mainly written for doctors or within specific specialties. This new anaemia guideline is for all registered professional staff including doctors, nurses and Allied Health Professionals, but it is also for patients, non-registered clinical staff and managerial and administrative staff. This should truly allow team-working building on everyone’s strengths and getting the best possible results for patients.