Norepinephrine (4mg/4ml)
Max concentration: 1.28 mg/ml
Solution: D5W only
Dosing instruction: Infusion rate: 0.02 - 3 µg/kg/min or 0.5-30 µg/min
Titrate dose by 0.05 µg/kg/min q 3mins to achieve MAP of 65 mmHg
Calculate ideal body weight
Height
cm.
Sex
Ideal Body Weight
kg.
Ideal body weight (IBW) (men) = 50 kg + 2.3 kg x (height, in - 60)
Ideal body weight (IBW) (women) = 45.5 kg + 2.3 kg x (height, in - 60)
This formula mainly applies to individuals 60 inches (5 feet) tall or taller. For those under 5 feet, subtract 2 to 5 pounds for each inch below 60 inches.
Body Weight
kg.
Norepinephrine 4 mg+D5W 100 ml
(40 mcg/ml)
Rate (ml/hr)
Norepinephrine 8 mg+D5W 100 ml
Rate (ml/hr)
Norepinephrine 4 mg+D5W 250 ml
Rate (ml/hr)
Norepinephrine 8 mg+D5W 250 ml
Rate (ml/hr)
Dose (µg/kg/min)
Weight descriptors for dose adjustment of ICU drugs in obese patients
Group | Drug | Recommended Dosing |
|---|---|---|
Analgesic | Fentanyl | LBW [1] |
Morphine | LBW [1] | |
Sedative | Dexmedetomidine | LBW [2] |
Midazolam | LD: TBW, MD: LBW [3] | |
Propofol | LD: LBW, MD: TBW [1] | |
Vasopressor & Inotropic | Dobutamine | IBW [7] |
Dopamine | IBW [7] | |
Epinephrine | IBW [7] | |
Levosimendan | TBW [8] | |
Milrinone | TBW [7] | |
Norepinephrine | IBW [7] | |
Beta-blocker | Esmolol | TBW [4] |
Labetalol | IBW [6] | |
Anti-arrhythmic | Lidocaine | LBW [5] |
Neuromuscular Blocking agent | Atracurium | IBW [1] |
Cisatracurium | IBW [1] | |
Anticoagulant | Enoxaparin | TBW [7] |
TBW: True body weight, LBW: Lean body weight, IBW: Ideal body weight, LD: loading dose, MD: maintenance dose
References
1) Ingrande J, Lemmens HJ. Dose adjustment of anaesthetics in the morbidly obese. Br J Anaesth. 2010 Dec;105 Suppl 1:i16-23. doi: 10.1093/bja/aeq312. PMID: 21148651.
2) Rolle A, Paredes S, Cortínez LI, Anderson BJ, Quezada N, Solari S, Allende F, Torres J, Cabrera D, Contreras V, Carmona J, Ramírez C, Oliveros AM, Ibacache M. Dexmedetomidine metabolic clearance is not affected by fat mass in obese patients. Br J Anaesth. 2018 May;120(5):969-977. doi: 10.1016/j.bja.2018.01.040. Epub 2018 Mar 28. PMID: 29661414.
3) Bian L. Critical Care Pharmacotherapy. 1 st ed. the United States of America: American College of Clinical Pharmacy; 2016.
4) Kane-Gill S, Dasta J, editors. High-Risk IV Medications in Special Patient Populations [Internet]. London: Springer London 2011 [cited 2025 May 8] Available from: https://link.springer.com/book/10.1007/978-0-85729-606-1
5) Tognolini AR, Liu X, Pandey S, Roberts JA, Wallis SC, Jackson D, Eley VA. Dosing optimisation of intravenous lidocaine in patients with class 1-3 obesity by population pharmacokinetic analysis. Anaesthesia. 2025 May;80(5):511-521. doi: 10.1111/anae.16531. Epub 2025 Jan 2. PMID: 39745506.
6) Cheymol G, Poirier JM, Carrupt PA, Testa B, Weissenburger J, Levron JC, Snoeck E. Pharmacokinetics of beta-adrenoceptor blockers in obese and normal volunteers. Br J Clin Pharmacol. 1997 Jun;43(6):563-70. doi: 10.1046/j.1365-2125.1997.00609.x. PMID: 9205815; PMCID: PMC2042788.
7) Erstad BL, Barletta JF. Drug dosing in the critically ill obese patient: a focus on medications for hemodynamic support and prophylaxis. Crit Care. 2021 Feb 23;25(1):77. doi: 10.1186/s13054-021-03495-8. PMID: 33622380; PMCID: PMC7901103.
8) Simdax. Simdax SPC [Internet] 2021 [Cited 08 May 2025]. Available from: https://www.simdax.com/siteassets/simdax-spc.pdf