title: Increased serum nitrite and nitrate concentrations in children with the sepsis syndrome.
abstract: OBJECTIVE
  To measure total serum nitrite and nitrate concentrations in children with the sepsis syndrome as an indicator of endogenous nitric oxide production. To determine if there is an association between total serum nitrite and nitrate concentrations and vascular responsiveness to norepinephrine.
  
  
  METHODS
  A prospective, clinical study.
  
  
  METHODS
  Tertiary, multidisciplinary, pediatric intensive care unit.
  
  
  METHODS
  Thirty-one children with the sepsis syndrome, 18 of whom were also hypotensive. Sixteen critically ill children without signs of the sepsis syndrome served as controls.
  
  
  METHODS
  Blood samples were obtained from indwelling catheters. The norepinephrine dose to reach the age appropriate, 50th percentile mean arterial blood pressure was determined in patients receiving norepinephrine.
  
  
  RESULTS
  Total serum nitrite and nitrate concentrations were measured on the first three days after the recognition of the sepsis syndrome. Patients with the sepsis syndrome had increased mean total serum nitrite and nitrate concentrations (day 1, 118 +/- 93 microM; day 2, 112 +/- 94 microM; day 3, 112 +/- 93 microM) vs. controls (43 +/- 24 microM, p < .05) on all 3 days. When sepsis syndrome patients were separated into nonhypotensive and hypotensive groups, only the patients with hypotension had increased concentrations vs. controls on all three days (p < .05). Sepsis syndrome patients with hypotension also had higher total serum nitrite and nitrate concentrations (145 +/- 97 microM) than sepsis syndrome patients without hypotension (82 +/- 76 microM, p < .05) on day 1. In five patients receiving norepinephrine infusions, increased total serum nitrite and nitrate concentrations were associated with higher norepinephrine requirements to maintain an age-appropriate, 50th percentile mean arterial blood pressure on each of the three study days (day 1, rs = 0.821, p < .05; day 2, rs = 0.900, p < .05; day 3, rs = 0.872, p < .05).
  
  
  CONCLUSIONS
  Children with the sepsis syndrome, particularly those patients with hypotension, have increased total serum nitrite and nitrate concentrations that likely reflect increased endogenous production of nitric oxide. Vascular hyporesponsiveness to norepinephrine during the sepsis syndrome may be, in part, a nitric oxide-mediated process.
authors.affiliation: Department of Anesthesiology, University of Pittsburgh School of Medicine, PA, USA.
authors.forename: H R
authors.initials: HR
authors.lastname: Wong
authors.forename: J A
authors.initials: JA
authors.lastname: Carcillo
authors.forename: G
authors.initials: G
authors.lastname: Burckart
authors.forename: N
authors.initials: N
authors.lastname: Shah
authors.forename: J E
authors.initials: JE
authors.lastname: Janosky
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007022:Hypotension / Q000097:blood / Q000188:drug therapy; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009566:Nitrates / Q000097:blood*; D009569:Nitric Oxide / Q000097:blood; D009573:Nitrites / Q000097:blood*; D009638:Norepinephrine / Q000008:administration & dosage; D011446:Prospective Studies; D018709:Statistics, Nonparametric; D018746:Systemic Inflammatory Response Syndrome / Q000097:blood* / Q000188:drug therapy; D013997:Time Factors
chemical_list: D009566:Nitrates; D009573:Nitrites; D009569:Nitric Oxide; D009638:Norepinephrine