title: Norepinephrine Dosing in Obese and Nonobese Patients With Septic Shock.
abstract: BACKGROUND
  Whether or not norepinephrine infusions for support of hemodynamic status in patients with septic shock should be weight based is unknown. This situation is particularly pertinent in patients who are extremely overweight or obese.
  
  
  OBJECTIVE
  To compare dosing requirements and effect of norepinephrine on blood pressure in obese and nonobese patients with septic shock.
  
  
  METHODS
  In a retrospective cohort study, data on adult patients with septic shock who received norepinephrine infusion for support of hemodynamic status in a tertiary care, academic medical center were analyzed. Patients were categorized as obese (body mass index ≥ 30) or nonobese (body mass index < 30). The primary outcome was dosing requirements of norepinephrine at 60 minutes after the start of the infusion. The secondary outcome was the log-transformed ratio of mean arterial pressure to norepinephrine.
  
  
  RESULTS
  The final cohort consisted of 100 obese and 100 nonobese patients. Mean norepinephrine infusion rate at 60 minutes was 0.09 (SD, 0.08) μg/kg per minute in the obese group and 0.13 (SD, 0.14) μg/kg per minute in the nonobese group (P = .006). The non-weight-based dose at 60 minutes was 9 μg/min in obese patients and 8 μg/min in nonobese patients (P = .72). The log transformed mean arterial pressure to norepinephrine ratio at 60 minutes was 2.5 (SD, 0.9) in obese patients and 2.5 (SD, 0.8) in nonobese patients (P = .54) CONCLUSIONS: Compared with nonobese patients, obese patients with septic shock require lower weight-based doses of norepinephrine and similar total norepinephrine doses.
authors.affiliation: John J. Radosevich is a clinical pharmacist, critical care, Pharmacy Department, St Joseph's Hospital and Medical Center, Phoenix, Arizona. Asad E. Patanwala is an associate professor and Brian L. Erstad is a professor and department head, Pharmacy Practice and Science, College of Pharmacy, University of Arizona, Tucson, Arizona.
authors.forename: John J
authors.initials: JJ
authors.lastname: Radosevich
authors.affiliation: John J. Radosevich is a clinical pharmacist, critical care, Pharmacy Department, St Joseph's Hospital and Medical Center, Phoenix, Arizona. Asad E. Patanwala is an associate professor and Brian L. Erstad is a professor and department head, Pharmacy Practice and Science, College of Pharmacy, University of Arizona, Tucson, Arizona. patanwala@pharmacy.arizona.edu.
authors.forename: Asad E
authors.initials: AE
authors.lastname: Patanwala
authors.affiliation: John J. Radosevich is a clinical pharmacist, critical care, Pharmacy Department, St Joseph's Hospital and Medical Center, Phoenix, Arizona. Asad E. Patanwala is an associate professor and Brian L. Erstad is a professor and department head, Pharmacy Practice and Science, College of Pharmacy, University of Arizona, Tucson, Arizona.
authors.forename: Brian L
authors.initials: BL
authors.lastname: Erstad
mesh_terms: D000368:Aged; D062186:Arterial Pressure / Q000187:drug effects*; D001835:Body Weight; D005260:Female; D005440:Fluid Therapy; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D009638:Norepinephrine / Q000008:administration & dosage*; D009765:Obesity / Q000150:complications*; D012189:Retrospective Studies; D012772:Shock, Septic / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology; D014662:Vasoconstrictor Agents / Q000008:administration & dosage*
chemical_list: D014662:Vasoconstrictor Agents; D009638:Norepinephrine