Cerebral Oximetry and Cognitive Dysfunction in Elderly Patients Undergoing Surgery for Hip Fractures: A Prospective Observational Study
George Papadopoulos1, Menelaos Karanikolas*, 2, Antonia Liarmakopoulou1, George Papathanakos1, Marianna Korre1, Alexander Beris3
1 Department of Anaesthesiology and Postoperative Intensive Care, University of Ioannina School of Medicine, Ioannina, Greece
2 Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri, USA
3 Department of Orthopaedic Surgery, University of Ioannina School of Medicine, Ioannina, Greece
This study was conducted to examine perioperative cerebral oximetry changes in elderly patients undergoing hip fracture repair and evaluate the correlation between regional oxygen saturation (rSO2) values, postoperative cognitive dysfunction (POCD) and hospital stay.
Materials and Methods:
This prospective observational study included 69 patients. Data recorded included demographic information, rSO2 values from baseline until the second postoperative hour and Mini Mental State Examination (MMSE) scores preoperatively and on postoperative day 7. MMSE score ≤23 was considered evidence of cognitive dysfunction. Postoperative confusion or agitation, medications administered for postoperative agitation, and hospital length of stay were also recorded. Data were analyzed with Student’s t-test, Pearson’s correlation or multiple regression analysis as appropriate.
Patient age was 74±13 years. Baseline left sided rSO2 values were 60±10 and increased significantly after intubation. Baseline rSO2 L<50 and <45 was observed in 11.6% and 10.1% of patients respectively. Perioperative cerebral desaturation occurred in 40% of patients. MMSE score was 26.23 ± 2.77 before surgery and 25.94 ± 2.52 on postoperative day 7 (p=0.326). MMSE scores ≤ 23 were observed preoperatively in 6 and postoperatively in 9 patients. Patients with cognitive dysfunction had lower preoperative hematocrit, hemoglobin, SpO2 and rSO2 values at all times, compared to patients who did not. There was no correlation between rSO2 or POCD and hospital stay. Patients with baseline rSO2 <5 required more medications for postoperative agitation.
Cognitive dysfunction occurs preoperatively and postoperatively in elderly patients with hip fractures, and is associated with low cerebral rSO2 values.
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* Address correspondence to this author at the Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri, USA; Tel: +1-314-3622340; Fax: +1-314-7472118; E-mails: email@example.com, firstname.lastname@example.org