Re-admission to Level 2 unit after hip-fracture surgery - Risk factors, reasons and outcome

Introduction: Hip fractures are common geriatric fractures with increasing incidence. Treatment of these fractures is still associated with high rates of complications and poor outcome. Data concerning unexpected re-admission to a Level 2 unit after an initial inconspicuous postoperative course are limited. We aimed to identify causes and associated risk factors for admission as well as impact of re-admission on acute care and short-term outcome. Patients and methods: Patients over 60 years of age with hip fractures were included in this prospective single-centre observational study. Patients with polytrauma or malignancy-associated fractures were excluded. Age, gender, fracture type, pre-fracture residential, physical and cognitive status, recording to the American Society of Anesthesiologists (ASA) score, Barthel Index (BI) and Mini-Mental State Examination (MMSE) were recorded on admission. Date, type of surgery and operation time were evaluated. Postoperatively, the prevalence of and reasons for unexpected re-admission to the Level 2 unit and patients' outcome were measured. Parameters were hospital mortality, BI at discharge, length of stay in hospital and type of discharge. Univariate and multivariate analyses were performed to identify risk factors for admission to the Level 2 unit and influence on patients' outcome. Results: Out of 402 included patients, 48 (12%) were re-admitted to the Level 2 unit. The most frequent reasons were non-surgical (n = 38), such as respiratory failure (n = 12), cardiovascular diseases (n = 8) and acute renal failure (n = 5). Ten patients were re-admitted due to a revision surgery of the hip. We identified two independent risk factors for readmission: male gender (odds ratio (OR) = 2.38, confidence interval (95% CI) = 1.10-5.15, p = 0.027) and type of fracture, especially femoral neck fracture (OR = 7.40, 95% CI = 2.39-23.26, p = 0.001). Patients who were re-admitted to the Level 2 unit had a higher mortality (b = 2.09, OR = 8.07, 95% CI = 2.44-26.75, p = 0.001), an increase in hospital stay (b = 7.0, 95% CI 5.2-8.7, p < 0.001) and a lower functional outcome (BI, b = -17, 95% CI = -23 to -10, p < 0.001). Conclusion: Unexpected admission to the Level 2 unit in the post-surgical period is a frequent phenomenon in geriatric hip-fracture patients. Males and femoral neck fracture patients seem to be especially endangered. Although the majority of reasons for admissions were not immediately lifethreatening illnesses, they had a substantial negative impact on patients' outcome. This emphasises the importance of careful handling of this frail patient population. (C) 2013 Elsevier Ltd. All rights reserved.