Table 3. Median red cell acetylcholinesterase activity (mU/µmol Hb) in patients surviving or dying, by study arm, at 1 and 24 h post-treatment.

Time Point	Characteristic	Placebo Arm	Pralidoxime Arm
Baseline, median (IQR)		28 (7 to 59)	44 (12 to 97)
1 h	n	101	103
	Dead, median (IQR)	6 (0 to 15)	40 (21 to 206)
	Alive, median (IQR)	31 (12 to 65)	286 (147 to 400)
	Difference, median (95% CI; p-value)	23 (12 to 34; p = 0.0003)	182 (97 to 249; p = 0.0001)
24 h	n	86	86
	Dead, median (IQR)	2 (0 to 8)	62 (0 to 287)
	Alive, median (IQR)	45 (12 to 84)	302 (115 to 407)
	Difference, median (95% CI; p-value)	40 (18 to 53; p = 0.002)	135 (27 to 251; p = 0.01)

This table shows that patients who were allocated pralidoxime and survived had substantially higher red cell acetylcholinesterase activity after treatment than patients receiving pralidoxime who died. Patients who survived without receiving pralidoxime had only a marginally higher acetylcholinesterase activity post-treatment than people who died. This indicates that reactivated red cell acetylcholinesterase may not be essential for survival. Normal mean (±SD) red cell acetylcholinesterase in the laboratory was 651±18 mU/µmol Hb [27].