Comparison of three point-of-care testing devices to detect hemostatic changes in adult elective cardiac surgery: a prospective observational study

Table 1 Nomenclature, variable definitions and reference ranges of the TEG, RoTEM and Sonoclot instruments

	TEG	RoTEM	Sonoclot
Clot time	R (Reaction time)	CT (Clotting time)	-
Time to 2 mm amplitude	(4–8 min.)	-EXTEM CT (42–74 sec)*
Time to 2 mm amplitude	(4–8 min.)	-INTEM CT (137–246 sec)
Clot kinetics	K (kinetics)	CFT (Clot formation time)	-
Time from 2 to 20 mm clot firmness	(1–4 min.)	-EXTEM CFT (46–148 sec)
Time from 2 to 20 mm clot firmness	(1–4 min.)	-INTEM CFT (40–100 sec)
Clot kinetics	Alpha angle	Alpha angle	-
Alpha angle	(53–67 deg)	-EXTEM angle (63–81 deg)
Alpha angle	(53–67 deg)	-INTEM angle (71–82 deg)
Clot strength	MA (Maximum amplitude)	MCF (Maximum Clot Firmness)	-
	MA (Maximum amplitude)	-EXTEM MCF ( 49–71 mm)
	(55–73 mm)	-INTEM MCF (52–72 mm)
	(55–73 mm)	-FIBTEM MCF (9–25 mm).
Clot elasticity	G (4.6-10.9 dynes/cm²)	-	-
Time until the beginning of fibrin formation	-	-	Son Act (85–145 sec)
Rate of fibrin formation	-	-	Clot Rate R1 (15–45 clot signal units/min)
Completion of fibrin formation	-	-	Peak (mm)
Index of fibrinogen conversion to fibrin	-	-	Time to Peak (540–600 sec)
Platelet-induced clot retraction	-	-	R3 (>2 mm/min)

*EXTEM reagent contains tissue factor, INTEM reagent contains ellagic acid, FIBTEM reagent contains platelet inhibitor.

ISSN: 1471-2253