PERIOPERATIVE HAEMOGLOBIN AND REHABILITATION AFTER TOTAL HIP OR KNEE ARTHROPLASTY: WHEN SHOULD BLOOD TRANSFUSION BE GIVEN?

Abstract

Introduction: Blood management in the perioperative period of the total joint arthroplasty procedure has evolved over the last 3 decades. We performed two separate studies:

1. 1) observational study to analyse surgeon’s and anaesthetist’s attitude to transfusion

2. 2) prospective study to analyse the influence of perioperative haemoglobin concentration (Hb) on post-operative fatigue, hand grip strength, duration of in-patient physiotherapy and post-operative morbidity score (POMS) and also the prognostic factors to predict functional recovery.

Method: 500 orthopaedic surgeons and 336 anaesthetists were surveyed to assess current UK attitudes towards transfusion practice following arthroplasty.

200 patients (88 THR, 99 TKR, 13 hip resurfacing) were evaluated. Blood Hb, hand grip strength and vigour scores using fatigue questionnaire were estimated both preoperatively and at 3 days following surgery. POMS and the required duration of in-patient physiotherapy were also noted. The protocol for blood transfusion was for those with Hb less than 8 g/dL and/or post-operative symptoms attributable to anaemia.

Results: In an uncomplicated patient following total hip arthroplasty, 53.2% of surgeons and 63.1% of anaesthetists would transfuse at or below Hb of 8g/dL. Mean transfusion threshold in surgeons was 8.3g/dL compared to 7.9g/dL for anaesthetists (p< 0.01). 97% of surgeons transfused two or more units compared to 78% anaesthetists (p< 0.01). This threshold Hb increased if patient was symptomatic (surgeons 9.3g/dL, anaesthetists 8.8g/dL, p< 0.05), or if known to have pre-existing ischaemic heart disease (surgeons 9.0g/dL, anaesthetists 9.2g/dL, p< 0.05).

A greater fall in postoperative Hb correlated significantly with a greater reduction in post-operative vigour score (p=0.02). Also a greater fall in vigour score was found to correlate significantly with the duration of in-patient physiotherapy (p< 0.001). A reduction in Hb of > 4g/dL from the pre-operative Hb predicted a significantly higher reduction in vigour score (p=0.03). A weak correlation was seen between a fall in Hb and POMS (p=0.09).

A higher pre-operative Hb did not reduce the required duration of in-patient physiotherapy (p=0.72). There was no correlation between post-operative Hb and POMS (p=0.21) or duration of in-patient physiotherapy (p=0.20).

A higher pre-operative grip strength predicted an early date of discharge by the physiotherapists (p=0.02).

Conclusion: Haemoglobin level below 9g/dL is the most common ‘trigger’ for blood transfusion. Surgeons tend to be more aggressive in their attitude to transfusion. A fall in Hb of more than 4 g/dL has a detrimental effect on post-operative rehabilitation. Pre-operative grip strength measurements are valuable in predicting the rehabilitation potential of patients undergoing lower limb arthroplasty.