Norepinephrine infusion for prophylaxis against spinal-induced hypotension in elderly patients undergoing hip surgery: a randomized controlled comparison of two doses.
Wahib M, Mostafa M, et al. • BMC anesthesiology • 2026
A norepinephrine infusion rate of 0.07 mcg/kg/min was not inferior to 0.1 mcg/kg/min in maintaining post-spinal mean arterial pressure in elderly patients undergoing hip surgery under spinal anesthesia.
Key Findings
Results
The 0.07 mcg/kg/min norepinephrine infusion rate was non-inferior to 0.1 mcg/kg/min for maintaining average intraoperative MAP after spinal anesthesia in elderly hip surgery patients.
Average intraoperative MAP was 87.9 ± 9.5 mmHg in the 0.1-mcg group and 84.5 ± 8.5 mmHg in the 0.07-mcg group.
The mean difference was -3.5 mmHg (95% CI: -7.4 to 0.4 mmHg).
Non-inferiority was declared because the lower bound of the 95% CI (-7.4 mmHg) did not cross the prespecified non-inferiority margin of 8 mmHg.
84 patients were analyzed in this randomized controlled trial.
MAP was recorded every 2 minutes for 46 minutes after spinal anesthesia.
Results
The incidence of post-spinal hypotension was comparable between the two norepinephrine dose groups.
Post-spinal hypotension was defined as MAP < 70% of baseline or < 65 mmHg.
The hypotension incidence was assessed as a secondary superiority outcome.
No statistically significant difference was found between the 0.1-mcg and 0.07-mcg groups for hypotension incidence.
Results
The incidence of reactive hypertension and bradycardia were comparable between the two norepinephrine dose groups.
Hypertension and bradycardia were assessed as secondary outcomes with a superiority framework.
Neither adverse event differed significantly between the 0.1-mcg/kg/min and 0.07-mcg/kg/min groups.
The authors concluded that 'both infusion rates had comparable profile regarding adverse events, namely reactive hypertension and bradycardia.'
Methods
The study was designed as a randomized non-inferiority clinical trial in elderly patients scheduled for hip surgery under spinal anesthesia.
Patients were randomized to receive norepinephrine at either 0.1 mcg/kg/min or 0.07 mcg/kg/min immediately after spinal anesthesia.
The primary outcome was the noninferiority comparison of average post-spinal MAP readings between the two groups.
The prespecified non-inferiority margin was 8 mmHg.
84 patients were included in the final analysis.
The trial was registered at ClinicalTrials.gov (NCT07077265).
What This Means
This research suggests that a lower dose of norepinephrine (0.07 micrograms per kilogram per minute) works just as well as the higher standard dose (0.1 micrograms per kilogram per minute) at preventing dangerous drops in blood pressure in elderly patients receiving spinal anesthesia for hip surgery. Spinal anesthesia commonly causes blood pressure to fall, which can be especially risky in older patients. Norepinephrine is a medication used to counteract this effect, and identifying the lowest effective dose is important for patient safety.
In this study of 84 elderly patients, blood pressure was monitored every two minutes for nearly an hour after spinal anesthesia was given. The average blood pressures in both groups were close enough that the lower dose was considered 'non-inferior,' meaning it performed within an acceptable range compared to the higher dose. Importantly, side effects such as blood pressure rising too high (reactive hypertension) and heart rate dropping too low (bradycardia) occurred at similar rates in both groups.
This research suggests that using the lower norepinephrine dose of 0.07 mcg/kg/min could be a viable option for managing blood pressure in elderly patients during hip surgery under spinal anesthesia, potentially offering an equivalent safety and efficacy profile to the higher dose. This finding could be relevant for clinical practice where fine-tuning drug dosing in vulnerable elderly populations is important, though further research in broader populations may be needed to confirm these results.
Wahib M, Mostafa M, Hasanin A, Alashmawy E, Mustafa M, Taha M, et al.. (2026). Norepinephrine infusion for prophylaxis against spinal-induced hypotension in elderly patients undergoing hip surgery: a randomized controlled comparison of two doses.. BMC anesthesiology. https://doi.org/10.1186/s12871-026-04174-3