Table 1

Description of the medical intensive care unit of Besançon hospital, June 1999 to May 2003
Parameter
 Period 1 (June 1999 to May 2001)
 Period 2 (June 2001 to May 2003)
 P
No. of patients admitted
 912
 987
Patients screened for MRSA (% of patients admitted)
 775 (84.5%)
 819 (83.0%)
 0.26
Mean length of stay, days
 11.44
 9.73
 0.02
Mean gravity score, SAPS II
 46.32
 46.44
 0.91
Rate of death, %
 32.73
 28.43
 0.07
MRSA cases
 46
 55
 0.59e
     Carriers of MRSAa (then infected)
 38 (1)
 49 (11)
 0.35g
     Infected with MRSAb
 9
 17
 0.24e
          Imported MRSAc
 6
 4
 0.66e
          Exogenous acquired MRSAc,d
 2
 2
 1.00f
          Endogenous acquired MRSAc,d
 1
 11
 0.006g

aPatients from whom methicillin-resistant Staphylococcus aureus (MRSA) was recovered from screening samples or from clinical samples without signs of infection. bPatients from whom MRSA was recovered from clinical samples with signs of infection in accordance with the definitions of the Centers for Disease Control and Prevention. cDefined as imported if they tested positive within 48 hours of admission, and as acquired if they tested negative for the first 48 hours after admission. dDefined as endogenous if a screening sample was positive before the clinical sample, and as exogenous otherwise. eIn comparison with admitted patients. fIn comparison with screened patients. gIn comparison with carriers of MRSA. SAPS II, Simplified Acute Physiology Score, SAPS II.

Muller et al. Critical Care 2005 9:R246   doi:10.1186/cc3512