Table 3.

Resistances to flow for the spinal needles and time constants calculated for P = 12 cmH₂O (From data of the reference paper [15])

Needle type	R (cm s/ml)	τ (s)
Sprotte 24G Atraumatic	2413.41	142.9
Spinocan 22G Quincke	1421.05	66.7
BD 22G Quincke	1064.04	55.6
BD 22G Whitacre	907.56	38.5
Sprotte 22G Atraumatic	667.7	25