Figure 1 - The Hillingdon Hospitals NHS Foundation Trust
Pre-operative anaemia optimisation protocol for elective total hip and
total knee arthroplasties. THR: Total Hip Replacement; TKR: Total Knee
Replacement; Hb: Haemoglobin; RBC: Red Blood Cells; GP: General
Practitioner; FBC: Full Blood Count; IV: Intravenous.
Upon the decision to proceed for surgery, patients are referred to the
pre-operative assessment clinic, where they undergo routine
investigations (full blood count, urea and electrolytes, group and save,
ECG) and an assessment of their medical co-morbidities. A protocol,
based on the NATA guidelines previously discussed, was created
specifically for patients undergoing elective primary hip or knee
replacement surgery. This would be initiated at the pre-operative
assessment clinic.
The haemoglobin and ferritin levels were evaluated, and patients who
were identified as anaemic (as defined by the WHO criteria of Hb
<12g/dL in non-pregnant women and Hb<13g/dL in men)
and have a serum ferritin level of <100ng/ml receive oral iron
therapy for four weeks through their GP. Where there is less than four
weeks before the date of surgery, patients received intravenous iron,
ferric carboxymaltose, instead.
These patients are then re-assessed to see if their anaemia has been
optimised. If there has been no response to oral therapy, patients are
then given intravenous iron therapy, provided that there are no
contra-indications. In patients with a serum ferritin level of more than
100 ng/mL and a Haemoglobin of less than 12 g/dL, discussion with the
haematology team is recommended to further investigate and address the
cause of anaemia.
We conducted a retrospective audit of patients who had undergone
elective primary total hip or total knee arthroplasty in 2016. A patient
database was obtained from the clinical coding department. We initially
analysed all patients’ blood results using the Trust’s electronic blood
test reporting system. Once the anaemic patients were identified from
their initial pre-operative assessment bloods, we used their inpatient
clinical notes, electronic discharge summaries and electronic GP records
to determine which patients received pre-operative anaemia correction
treatment.
683 patients were included in the audit from the database that had
undergone surgery between January 1st 2016 and December 31st 2016. From
the same database, 21 patients were excluded for a variety of reasons -
18 patients had revision arthroplasty surgeries, 1 patient had bilateral
joint replacement surgery, 1 patient was receiving blood transfusions on
a regular basis prior to surgery for a complex haematological condition,
and 1 patient had no discharge summary. From this, we established that
138 patients were identified as being anaemic at pre-operative
assessment clinic (20.2% of the cohort population).
Only 25 of the 138 anaemic patients were correctly identified and
managed with regards to their anaemia and the pre-operative assessment
protocol (18.1%).
Following on from the results of the audit, we decided to examine what
impact anaemia and the subsequent management protocol had on hospital
length of stay and blood transfusion requirement. This was done by 2
methods: For hospital length of stay we obtained the information from
patients’ electronic discharge summaries. For blood transfusions, we
used the Trust’s electronic blood test and investigation reporting
system to determine how many units of blood were issued for each patient
(if any) and cross referenced with their electronic discharge summaries.
The length of stay and blood transfusion rates were calculated for both
anaemic and non-anaemic patients.