Perioperative Erythropoietin Administration can reduce Delirium in Older Adults after Total Joint Arthroplasty: Study

Post-operative delirium, also known as PD, is described as a clinical condition characterized by sudden changes in consciousness, disorganized thoughts, and impaired attention following surgery. The prevalence of PD can range significantly across different groups, impacting as many as 60% of susceptible populations. Recent study aimed to examine the role of perioperative administration of erythropoietin (EPO) in the development of post-operative delirium in older adult patients undergoing total joint arthroplasty. Post-operative delirium is a common complication with significant clinical and financial impacts on patients. EPO has anti-inflammatory properties, and the researchers investigated whether perioperative EPO administration can influence the occurrence of post-operative delirium in this patient population.

Seventy-one patients over 65 years old scheduled for total joint arthroplasty were randomly assigned to either an EPO-treated group (n=35) or a placebo control group (n=36). All patients underwent cognitive and delirium assessments before and after surgery. Serum C-reactive protein (CRP) and inflammatory cytokine levels were also measured.

The results showed that one patient in the control group developed delirium on post-operative day 2, while no patients in the EPO group developed delirium (0% vs 3.2%, p=0.500). Post-operatively, there were no significant differences in Mini-Mental State Examination (MMSE) scores between the groups. Both groups showed increases in pro- and anti-inflammatory cytokine levels, with no significant differences between the groups. Similarly, CRP levels, neutrophil/lymphocyte ratio, and platelet/lymphocyte ratio showed no intergroup differences in post-operative inflammatory responses.

Conclusion and Limitations

In conclusion, perioperative EPO administration reduced the incidence of post-operative delirium, although not statistically significant, with no differences in post-operative cognitive function and inflammatory responses. The authors suggest that future larger-scale, long-term studies are needed to confirm the effects of EPO on post-operative neurocognitive disorders. The study's limitations include the small sample size, single-center design, and lack of long-term follow-up for cytokines, neurocognitive assessment, and neuroinflammation.

Key Points

1. The study aimed to examine the role of perioperative administration of erythropoietin (EPO) in the development of post-operative delirium in older adult patients undergoing total joint arthroplasty.

2. Seventy-one patients over 65 years old scheduled for total joint arthroplasty were randomly assigned to either an EPO-treated group (n=35) or a placebo control group (n=36). All patients underwent cognitive and delirium assessments before and after surgery, and serum C-reactive protein (CRP) and inflammatory cytokine levels were measured.

3. The results showed that one patient in the control group developed delirium on post-operative day 2, while no patients in the EPO group developed delirium (0% vs 3.2%, p=0.500). There were no significant differences in Mini-Mental State Examination (MMSE) scores between the groups post-operatively.

4. Both groups showed increases in pro- and anti-inflammatory cytokine levels, with no significant differences between the groups. Similarly, CRP levels, neutrophil/lymphocyte ratio, and platelet/lymphocyte ratio showed no intergroup differences in post-operative inflammatory responses.

5. The authors concluded that perioperative EPO administration reduced the incidence of post-operative delirium, although not statistically significant, with no differences in post-operative cognitive function and inflammatory responses.

6. The study's limitations include the small sample size, single-center design, and lack of long-term follow-up for cytokines, neurocognitive assessment, and neuroinflammation. The authors suggest that future larger-scale, long-term studies are needed to confirm the effects of EPO on post-operative neurocognitive disorders.

Reference –

Kim, E.J., Park, K.K., Choi, S.Y. et al. Erythropoietin for the prevention of postoperative neurocognitive disorder in older adult patients undergoing total joint arthroplasty: a randomized controlled study. BMC Anesthesiol 24, 418 (2024). https://doi.org/10.1186/s12871-024-02770-9