A contemporary description of patients’ estimated blood losses from diagnostic phlebotomy in a census of hospital episodes from a Canadian tertiary care center

Abstract

BACKGROUND: Phlebotomy for diagnostic testing is among the commonest hospital procedures, but hospitalwide surveys of all inpatients characterizing blood draw volumes have not been published. The objectives were to characterize the daily blood volumes drawn for diagnostic testing from patients discharged from a Canadian tertiary care center, describe the daily distributions of phlebotomy volumes across service locations, and describe changes in hemoglobin (Hb) and transfusion across service locations. STUDY DESIGN AND METHODS: Data wereobtained on all patients discharged between 2012 and 2014 using linked discharge abstract and laboratory data. Cumulative daily blood volume and draw frequency were reported by service and days since admission. Changes in Hb and red blood cell (RBC) transfusion rates were reported for nontransfused and transfused patients.RESULTS: Data were included on 59,715 subjects.Mean daily estimated blood loss varied from 8.5 AE 6.5 mL/day onward to 27.2 AE 20.0 mL/day in the intensive care unit (ICU; p < 0.001). Phlebotomy volumes were highest on the first day of admission and declined thereafter (p < 0.001). For nontransfused individuals in the first week of admission, Hb levels decreased by the highest percentage in the ICU. The rate of RBC unit transfusion was highest in the ICU (232.4 units/1000 patient-days; 95% confidence interval, 225.8-239.2; p < 0.0001 compared with all other locations). CONCLUSION:Considerable variation was observed in estimated blood loss due to diagnostic phlebotomy across different services within one teaching hospital. Thi information is foundational for planning interventions to minimize estimated blood loss from phlebotomy.ABBREVIATIONS: AMI = acute myocardial infarction; ICU = intensive care unit; IMCU(s) = medical intermediate care unit(s);

Avoidable Blood Loss in Critical Care and Patient Blood Management: Scoping Review of Diagnostic Blood Loss

“…In patients receiving intensive care for more than 7 days, hemoglobin decreased by −0.6 ± 0.6 g/dL during the first three days [11]. The median Hb decreased by about −10.2 ± 15% during the first week on ICU [33].…”

“…The volume of blood typically needed for BGA is approximately 2 mL, for serum chemistries it is 7.5 mL, for citrate tubes it is 4.3 mL, for EDTA it is 2.7 mL, and it is up to 6 × 10-20 mL for blood cultures. A systematic review by Siegal et al pointed out that only 10% of collected 3: General ICU [1,9,10,46,49,50,60]; Medical ICU [27,29,47,48,51,54]; Medical/surgical ICU [11,56,57,62]; Surgical ICU [33,64]; other ICU [32,52,53,55,59,61,63,65].…”

“…The authors also revealed an independent correlation between the increased use of phlebotomy and the risk to develop hospital acquired anemia [29]. 3: General ICU [1,9,10,46,49,50,60]; Medical ICU [27,29,47,48,51,54]; Medical/surgical ICU [11,56,57,62]; Surgical ICU [33,64]; other ICU [32,52,53,55,59,61,63,65].…”

“…Depending on the study design, PETAL network recommended a maximal research blood volume of 120 mL/d [31]. The estimated blood loss is much higher in ICU patients than in a surgical ward (up to 10 mL/day) or in renal inpatients [32,33]. Particularly on the day of ICU admission, the volume of daily blood collected for diagnostic purposes is the highest and decreases during the ICU stay [1,33].…”

“…Vincent et al found in >1000 patients in Western European ICUs an average blood loss for diagnostics of up to 41.1 mL/d [52]. Quinn et al and Chornenki et al revealed comparable amounts of blood loss in North American ICU patients and in Canada [33,57]. Most of the studies included data from either surgical or general ICUs.…”