6. Treatment for hypotension.

study	preload	treatment criteria
Alahuhta	1000 ml balanced electrolyte solution + 10 ml/kg preload	Ephedrine when systolic blood pressure < 100 mmHg or > 30% control
Ledan	All patients received 1000 ml of Ringer‐lactate solution and 30 mg subcutaneous ephedrine before having regional anaesthesia	Hypotension (systolic blood pressure < 100 mmHg or a fall of 30% from pre‐anaesthetic level) was treated with 10 mg ephedrine and infusion of Ringer‐lactate solution
Lertakyamanee	All patients received 1 litre of Ringer lactate as preload before the blocks were performed, and had a small pillow under the right buttock to prevent supine hypotension	Ephedrine was given if systolic blood pressure decreased more than 20% of baseline
Mahajan	750‐1000 ml of balanced salt solution within 5‐10 minutes after injection of LA	Ephedrine when systolic blood pressure decreased > 25% from pre‐anaesthetic values
Saito	IV fluids given "as necessary to maintain normal hemodynamic values" but "patients in both groups were given comparable amounts of intravenous fluids"	Ephedrine (5 mg boluses) was administered to maintain systolic arterial pressure > 90 mmHg
Vegfors	All patients received a preload of 1000 ml Ringer lactate and Macrodex 500 ml 25‐30 minutes before institution of blockade	Hypotension (systolic blood pressure < 100 mmHg) was treated with volume infusion and 5‐10 mg ephedrine iv
DATA NOT USED
Erbay	Reported as higher ephedrine requirement in spinal group, but no numbers reported
Helbo‐Hansen	Reported as doses given but not number of patients treated
Jani	More ephedrine used in spinal group ‐ but no numbers reported
Olofsson	All patients received an iv fluid preload but prophylaxis against hypotension was not standardised ie. timing of ephedrine injection different between groups