Table 1

Comparison of the devices, with flow rates and pressures. Devices and pressures that did not produce flow rate above the clinically useful minimum 30 mL/min, or where the pressures were over 150 mmHg, have been greyed out

				Flow rates for given Pressures (mL/min) Whole Milk				Pressure for given flows (mm Hg) (access/return) Equine blood
		Length (mm)	Manufacturer	50 mm Hg	100 mm Hg	150 mm Hg	200 mm Hg	20 mL/min	30 mL/min	40 mL/min	50 mL/min
Intravenous access devices	8Fr haemodialysis catheter	125	Gambro	33	85	128	149	−43/21	−61/36	−81/55	−96/76
	6.5Fr haemodialysis catheter	75	Gambro	33	78	101	129	−51/18	−68/38	−89/60	−108/80
	18G cannula	45	Jelco (Smiths)	23	60	82	100	−53/32	−76/44	−100/68	−123/97
	20G cannula	32	Jelco (Smiths)	21	47	64	77	−63/38	−94/57	−121/86	−146/120
	5Fr central line	50	Cook	10	26	39	47	−132/111	−168/169	−198/237	−223/309
	5Fr haemodialysis catheter	650	Baxter	9	27	39	44	−114/157	−157/220	−195/323	−240/352
	5Fr umbilical line	400	Vygon	12	22	30	36	−205/184	−238/295
	4Fr umbilical line	400	Vygon	8	15	20	25	Maximal pressure exceeded for all runs
Connectors	Three-way tap			51	89	168	224	−31/5	−43/13	−53/26	−64/35
	20G + needle-free valve			22	55	75	90
	15 cm lectrocath	150	Vygon					−79/52	−114/79	−148/117	−178/145