Importance and Aims of Patient Blood Management

For patients with severe anaemia or haemorrhage, blood transfusions have been shown to be life-saving.1 However, the default use of allogeneic blood transfusions for the treatment of anaemia may not be the optimal use of this valuable and limited resource.1

Evidence to support the benefit of blood transfusions is lacking, particularly in haemodynamically stable patients undergoing elective surgery.1 There is also mounting evidence that receiving a blood transfusion is an independent risk factor for adverse events.1,9,10 In observational studies, blood transfusions have been associated with an increased risk of:1,9,10

  • Morbidity and mortality
  • Postoperative infection
  • Acute respiratory distress syndrome and multi-organ failure
  • Prolongation of intensive care admission and/ or length of hospital stay

In addition to uncertainty over efficacy and safety concerns, blood transfusions are also costly and their costs are rising.1,9,10 Patients themselves may be increasingly reluctant to receive a blood transfusion due to increasing awareness and concern over the possible transmission of viral diseases.1,9,10

Patient blood management is multimodal, multidisciplinary, patient-centric care that aims to improve patient outcomes by minimizing the unnecessary use of allogeneic blood transfusions, thereby preserving the allogeneic blood resource for situations when truly indicated.2 This is achieved by addressing anaemia, blood loss and hypoxia as modifiable risk factors for blood transfusion, long before transfusion would even be considered.3

Optimizing Patient Blood Management


Patient blood management is implemented via three pillars:4

  1. Optimizing erythropoiesis
  2. Minimizing blood loss
  3. Harnessing and optimizing the patient-specific reserve of anaemia

In elective surgery, these three pillars are implemented pre-, intra-, and post-operatively via methods such as those described in Figure 1 below. In the emergency or trauma setting, there is little time to optimize the patient pre-operatively, so intra- and post-operative patient optimization is intensively employed.4

Figure 1: Implementing the three pillars of Patient Blood Management in the pre-, intra-, and post-operative settings4

 

  1st Pillar
Optimising erythropoiesis
2nd Pillar
Minimising blood loss
3rd Pillar
Harnessing and optimising the patient-specific reserve of anaemia
Preoperative Detect anaemia

Identify underlying disorder causing anaemia

Manage disorder

Appropriately treat anaemia and any haematinic deficiencies e.g. iron deficiency
Identify and manage bleeding risks

Minimise iatrogenic blood loss

Plan and rehearse operative procedures

Preoperative autologous blood donation (in certain patients and dependent on patient choice)
Assess/optimise patient's physiological reserve and risk factors

Compare estimated blood loss with patient-specific tolerable blood loss

Formulate patient-specific management plan using appropriate blood conservation modalities

Use restrictive transfusion thresholds
Intraoperative Time surgery to coincide with haematological optimisation Meticulous haemostasis and surgical techniques

Blood-sparing surgical techniques

Blood-conserving anaesthetic techniques

Autologous blood options

Pharmacological/haemostatic agents
Optimise cardiac output

Optimise ventilation and oxygenation

Use restrictive transfusion thresholds
Postoperative Stimulate erythropoiesis

Be aware of drug interactions that can cause or exacerbate anaemia
Vigilant monitoring and management of post-operative bleeding

Avoid secondary haemorrhage

Rapid warming/ maintain normothermia (unless hypothermia specifically indicated)

Autologous blood salvage

Minimise iatrogenic blood loss

Haemostasis/anticoagulation management

Prophylaxis of upper gastrointestinal haemorrhage

Avoid/treat infections promptly

Be aware of bleeding-related adverse effects of medication
Optimize anaemia reserve

Maximise oxygen delivery

Minimise oxygen consumption

Avoid/treat infections promptly

Use restrictive transfusion thresholds

 

 

Benefits of Patient Blood Management Programs


Numerous studies have proven the benefits of patient blood management strategies in terms of reducing the need for allogeneic blood transfusions.5 Specifically, use of iron therapy and/or recombinant human erythropoietin (rHuEPO) to correct preoperative anaemia has been shown to significantly reduce the rate of allogeneic blood transfusions in orthopaedic surgery.5 Preoperative iron therapy also significantly reduced postoperative infection rates,5 while preoperative rHuEPO significantly improved a quality of life score.5

Use of cell salvage measures where a patient’s perioperative shed blood is re-transfused, or preoperative autologous blood donation also reduces the rate of allogeneic blood transfusion.5 In addition, cell salvage measures have been shown to significantly reduce the mean length of a patient’s hospital stay.5

Studies have also compared the effectiveness of holistic patient blood management programs with usual care. A Canadian cluster-randomized trial found that use of a blood conservation algorithm in patients undergoing total hip-joint arthroplasty reduced the rate of allogeneic blood transfusions in comparison with usual care, however there were no significant differences in length of hospital stay.5 Similarly, in a US case-control study, use of a blood-conservation program during cardiac surgery successfully reduced the need for transfusions, but also reduced the risk of death and serious complications.6

In addition to improving patient outcomes, in the Netherlands implementation of patient blood management is estimated to have saved €100 million nationwide every year by reducing the number of allogeneic blood transfusions by 12% over the period 2000 to 2009.2

A focus on anaemia in elective surgery


Prevalence and consequences of preoperative anaemia

A number of studies have shown that the prevalence of preoperative anaemia is in the range of 24% to 44%,2 however up to 75% of patients undergoing colorectal surgery have been observed as being anaemic.2

In elective orthopaedic surgery such as total hip arthroplasty where mean blood loss is estimated at 1500ml 2, the incidence of anaemia rose from a preoperative level of 31% to a postoperative level of 51% in one study.5

Preoperative anaemia is associated with a number of adverse postoperative outcomes such as the following:

  • Increased risk of allogeneic blood transfusion7
  • Increased risk of mortality2
  • Increased morbidity including infectious complications2,7
  • Longer hospital stay and increased associated costs2,7

Screening for and treating preoperative anaemia

Although there are multiple possible causes of anaemia in preoperative patients, iron deficiency has been shown to be the predominant cause in elective surgery patients.7 Consequently, hospitals in a number of European countries routinely test a patient’s haemoglobin levels and iron status approximately 4 weeks before an elective surgery.2

It may be particularly pertinent to screen for low haemoglobin levels in patients at a higher risk for perioperative anaemia.

Evidence suggests that treating preoperative anaemia can reduce the need for allogeneic blood transfusions, reduce infection rates and increase quality of life.5 In a number of European countries, an attempt is therefore made to correct preoperative anaemia prior to surgery with rHuEPO, iron therapy and/or vitamin B12 supplementation.2

Figure 2 below shows an example of an algorithm advocated by Kotzé et al. in the UK for the screening and treatment of preoperative anaemia in primary hip replacement.8

Figure 2: Example preoperative blood management algorithm for primary hip replacement8

 

Avoiding transfusions chart