The feasibility and impact of midnight routine blood draws on laboratory orders and processing time

To evaluate the feasibility of midnight routine blood draws and assess their impact on test result availability and stat laboratory orders.

We changed the timing of routine blood draws from early morning to midnight on five inpatient wards during the period November 16 to 30, 2011.

For the entire institution, of all orders placed each day, laboratory test orders placed from 4:00 to 8:00 am decreased from 55% to 39%, and those placed from 12:00 to 4:00 am increased from 12% to 30%. Stat orders per day decreased during the intervention period (301 ± 53 vs 344 ± 55, P = .04). Morning specimens were more likely to be available by 9:00am (78.1% vs 58.9%, P < .001), and their turnaround time improved by 25.8 minutes (158 vs 184 minutes, P < .001). Patient survey revealed potential preference for midnight blood draws.

Midnight is a feasible alternative for the timing of routine blood draws. Redesigning inflow of laboratory orders improved efficiency of laboratory processing and reduced stat orders.