Discussion
hypotension
HYPOTENSIVE EPISODE
We found that infusing norepinephrine under SA with propofol sedation during hip surgery in patients aged ≥ 70 years was effective in decreasing the number of hypotensive episodes per patient and the incidence of hypotension during SA with intravenous propofol infusion.Lower extremity surgery represents 24% of all interventions among patients aged ≥ 75 yearsAs the degree of hypotension is proportional to the height of the sympathetic nerve blockSeveral strategies, including intravenous fluid administration and vasopressors, have been considered to prevent the occurrence of hypotension after SA induction. Prophylactic administration of crystalloid before SA is effective at preventing hypotension, at least in some patientsThe use of alpha-agonists to treat hypotension associated with SA has been extensively studied in the field of obstetrics. Phenylephrine, a pure alpha1-adrenergic receptor agonist that has no direct effect on HR, showed a beneficial effect during SA for cesarean deliveryAlthough more than 100 definitions of hypotension are mentioned in the literature, Salmasi et al. found that there was no advantage to using relative over absolute thresholdsThis study had several limitations. First, PVi values were measured during spontaneous breathing. PVi is a measure of the variations in the pulse oximeter waveform over respiratory cycles in non-invasive and continuous manner. When mechanical ventilation is employed, PVi can be considered reliableIn conclusion, the present study showed that prophylactic norepinephrine continuous intravenous infusion prevented hypotensive episodes, reduced the occurrence of hypotension and the requirement of fluid, and increased the urine output in older patients undergoing unilateral hip surgery under SA with propofol sedation.