title: Can venous base excess replace arterial base excess as a marker of early shock and a predictor of survival in trauma?
abstract: BACKGROUND
  Arterial base excess is an established marker of shock and predictor of survival in trauma patients. However, venous blood is more quickly and easily obtained. This study aimed to determine if venous base excess could replace arterial base excess as a marker in trauma patients at presentation and if venous base excess is predictive of survival at 24 hours and one week.
  
  
  METHODS
  This was a prospective study of 394 trauma patients presenting to the emergency department of a tertiary hospital over a 17-month period. Data on base excess at presentation, vital signs, shock index (SI), injury severity score (ISS), and mortality at 24 hours and one week was collected and analysed.
  
  
  RESULTS
  Arterial and venous blood gas tests were performed on 260 and 134 patients, respectively. Patients were stratified into groups based on their SI and ISS for analysis. There was no statistical difference between mean venous blood gas and arterial blood gas levels at presentation when SI > 0.7, regardless of ISS (p > 0.05). The mortality rate was 4.57%. Both venous and arterial base excess was lower in nonsurvivors compared to survivors (p < 0.05). However, at 24 hours and one week, the difference in base excess values at presentation between survivors and nonsurvivors was greater when using venous base excess compared to arterial base excess (11.53 vs. 4.28 and 11.41 vs. 2.66, respectively).
  
  
  CONCLUSIONS
  In conclusion, venous base excess can replace arterial base excess in trauma patients as a means of identifying and prognosticating early shock.
authors.affiliation: Department of General Surgery, Changi General Hospital, Singapore.
authors.forename: Ramesh
authors.initials: R
authors.lastname: Wijaya
authors.affiliation: Department of Otolaryngology, SingHealth, Singapore.
authors.forename: Jia Hui
authors.initials: JH
authors.lastname: Ng
authors.affiliation: Department of General Surgery, SingHealth, Singapore.
authors.forename: Lester
authors.initials: L
authors.lastname: Ong
authors.affiliation: Department of General Surgery, Changi General Hospital, Singapore.
authors.forename: Andrew Siang Yih
authors.initials: AS
authors.lastname: Wong
mesh_terms: D000137:Acid-Base Imbalance / Q000097:blood* / Q000209:etiology / Q000401:mortality; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001158:Arteries; D015415:Biomarkers / Q000097:blood*; D001774:Blood Chemical Analysis; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015601:Injury Severity Score; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012774:Shock, Traumatic / Q000097:blood* / Q000150:complications / Q000453:epidemiology; D012846:Singapore / Q000453:epidemiology; D015996:Survival Rate / Q000639:trends; D013997:Time Factors; D014193:Trauma Centers; D014680:Veins; D014947:Wounds and Injuries / Q000097:blood* / Q000150:complications / Q000175:diagnosis; D055815:Young Adult
chemical_list: D015415:Biomarkers
keywords: arterial; base excess; survival; trauma; venous