title: Re-admission to Level 2 unit after hip-fracture surgery - Risk factors, reasons and outcome.
abstract: BACKGROUND
  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.
  
  
  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 (β=2.09, OR=8.07, 95% CI=2.44-26.75, p=0.001), an increase in hospital stay (β=7.0, 95% CI 5.2-8.7, p<0.001) and a lower functional outcome (BI, β=-17, 95% CI=-23 to -10, p<0.001).
  
  
  CONCLUSIONS
  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 life-threatening illnesses, they had a substantial negative impact on patients' outcome. This emphasises the importance of careful handling of this frail patient population.
authors.affiliation: Department of Trauma, Hand and Reconstructive Surgery, University of Giessen and Marburg, Baldingerstrasse, 35043 Marburg, Germany. Electronic address: buecking@med.uni-marburg.de.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Buecking
authors.forename: Daphne
authors.initials: D
authors.lastname: Eschbach
authors.forename: Christos
authors.initials: C
authors.lastname: Koutras
authors.forename: Thomas
authors.initials: T
authors.lastname: Kratz
authors.forename: Monika
authors.initials: M
authors.lastname: Balzer-Geldsetzer
authors.forename: Richard
authors.initials: R
authors.lastname: Dodel
authors.forename: Steffen
authors.initials: S
authors.lastname: Ruchholtz
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003422:Critical Care / Q000706:statistics & numerical data*; D005260:Female; D005265:Femoral Neck Fractures / Q000401:mortality / Q000503:physiopathology / Q000601:surgery*; D016330:Frail Elderly / Q000706:statistics & numerical data; D005858:Germany / Q000453:epidemiology; D006620:Hip Fractures / Q000401:mortality / Q000503:physiopathology / Q000601:surgery*; D017052:Hospital Mortality; D006801:Humans; D016015:Logistic Models; D008297:Male; D010359:Patient Readmission / Q000706:statistics & numerical data; D011184:Postoperative Period; D011379:Prognosis; D011446:Prospective Studies; D012307:Risk Factors
keywords: Complication; Function; Geriatric fracture; Higher level of care; Hip fracture; Intensive care; Mortality; Outcome