title: Cumulative radiation exposure from diagnostic imaging in intensive care unit patients.
abstract: OBJECTIVE
  To quantify cumulative effective dose of intensive care unit (ICU) patients attributable to diagnostic imaging.
  
  
  METHODS
  This was a prospective, interdisciplinary study conducted in the ICU of a large tertiary referral and level 1 trauma center. Demographic and clinical data including age, gender, date of ICU admission, primary reason for ICU admission, APACHE II score, length of stay, number of days intubated, date of death or discharge, and re-admission data was collected on all patients admitted over a 1-year period. The overall radiation exposure was quantified by the cumulative effective radiation dose (CED) in millisieverts (mSv) and calculated using reference effective doses published by the United Kingdom National Radiation Protection Board. Pediatric patients were selected for subgroup-analysis.
  
  
  RESULTS
  A total of 2737 studies were performed in 421 patients. The total CED was 1704 mSv with a median CED of 1.5 mSv (IQR 0.04-6.6 mSv). Total CED in pediatric patients was 74.6 mSv with a median CED of 0.07 mSv (IQR 0.01-4.7 mSv). Chest radiography was the most commonly performed examination accounting for 83% of all studies but only 2.7% of total CED. Computed tomography (CT) accounted for 16% of all studies performed and contributed 97% of total CED. Trauma patients received a statistically significant higher dose [median CED 7.7 mSv (IQR 3.5-13.8 mSv)] than medical [median CED 1.4 mSv (IQR 0.05-5.4 mSv)] and surgical [median CED 1.6 mSv (IQR 0.04-7.5 mSv)] patients. Length of stay in ICU [OR = 1.12 (95%CI: 1.079-1.157)] was identified as an independent predictor of receiving a CED greater than 15 mSv.
  
  
  CONCLUSIONS
  Trauma patients and patients with extended ICU admission times are at increased risk of higher CEDs. CED should be minimized where feasible, especially in young patients.
authors.affiliation: Fiachra Moloney, Daniel Fama, Maria Twomey, Kevin P Murphy, Siobhan B O'Neill, Owen J O'Connor, Michael M Maher, Department of Radiology, Cork University Hospital, Wilton, 014 Cork, Ireland.
authors.forename: Fiachra
authors.initials: F
authors.lastname: Moloney
authors.affiliation: Fiachra Moloney, Daniel Fama, Maria Twomey, Kevin P Murphy, Siobhan B O'Neill, Owen J O'Connor, Michael M Maher, Department of Radiology, Cork University Hospital, Wilton, 014 Cork, Ireland.
authors.forename: Daniel
authors.initials: D
authors.lastname: Fama
authors.affiliation: Fiachra Moloney, Daniel Fama, Maria Twomey, Kevin P Murphy, Siobhan B O'Neill, Owen J O'Connor, Michael M Maher, Department of Radiology, Cork University Hospital, Wilton, 014 Cork, Ireland.
authors.forename: Maria
authors.initials: M
authors.lastname: Twomey
authors.affiliation: Fiachra Moloney, Daniel Fama, Maria Twomey, Kevin P Murphy, Siobhan B O'Neill, Owen J O'Connor, Michael M Maher, Department of Radiology, Cork University Hospital, Wilton, 014 Cork, Ireland.
authors.forename: Ruth
authors.initials: R
authors.lastname: O'Leary
authors.affiliation: Fiachra Moloney, Daniel Fama, Maria Twomey, Kevin P Murphy, Siobhan B O'Neill, Owen J O'Connor, Michael M Maher, Department of Radiology, Cork University Hospital, Wilton, 014 Cork, Ireland.
authors.forename: Conor
authors.initials: C
authors.lastname: Houlihane
authors.affiliation: Fiachra Moloney, Daniel Fama, Maria Twomey, Kevin P Murphy, Siobhan B O'Neill, Owen J O'Connor, Michael M Maher, Department of Radiology, Cork University Hospital, Wilton, 014 Cork, Ireland.
authors.forename: Kevin P
authors.initials: KP
authors.lastname: Murphy
authors.affiliation: Fiachra Moloney, Daniel Fama, Maria Twomey, Kevin P Murphy, Siobhan B O'Neill, Owen J O'Connor, Michael M Maher, Department of Radiology, Cork University Hospital, Wilton, 014 Cork, Ireland.
authors.forename: Siobhan B
authors.initials: SB
authors.lastname: O'Neill
authors.affiliation: Fiachra Moloney, Daniel Fama, Maria Twomey, Kevin P Murphy, Siobhan B O'Neill, Owen J O'Connor, Michael M Maher, Department of Radiology, Cork University Hospital, Wilton, 014 Cork, Ireland.
authors.forename: Owen J
authors.initials: OJ
authors.lastname: O'Connor
authors.affiliation: Fiachra Moloney, Daniel Fama, Maria Twomey, Kevin P Murphy, Siobhan B O'Neill, Owen J O'Connor, Michael M Maher, Department of Radiology, Cork University Hospital, Wilton, 014 Cork, Ireland.
authors.forename: Dorothy
authors.initials: D
authors.lastname: Breen
authors.affiliation: Fiachra Moloney, Daniel Fama, Maria Twomey, Kevin P Murphy, Siobhan B O'Neill, Owen J O'Connor, Michael M Maher, Department of Radiology, Cork University Hospital, Wilton, 014 Cork, Ireland.
authors.forename: Michael M
authors.initials: MM
authors.lastname: Maher
keywords: Computed tomography; Cumulative effective dose; Intensive care unit; Pediatric patients; Radiation dose