title: Intravenous clonidine administration and its ability to reduce pulmonary arterial pressure in patients undergoing heart surgery.
abstract: OBJECTIVE
  Evaluate the ability of clonidine to reduce pulmonary arterial pressure in patients with pulmonary hypertension undergoing heart surgery, either by reducing the pressure values from the direct measurement of pulmonary arterial pressure or by reducing or eliminating the need for intraoperative dobutamine and nitroprusside.
  
  
  METHODS
  Randomized, double-blind, placebo-controlled, comparative study conducted in 30 patients with pulmonary arterial hypertension type 2 undergoing cardiac surgery. Mean pulmonary arterial pressure and dosage of dobutamine and sodium nitroprusside were assessed four times: before intravenous administration of clonidine (2 μg/kg) or placebo (T0), 30 min after tested treatment and before cardiopulmonary bypass (T1), immediately after CPB (T2), 10 min after protamine injection (T3).
  
  
  RESULTS
  There were no significant differences regarding mean pulmonary arterial pressure at any time of evaluation. There was no significant difference between groups regarding other variables, such as mean systemic arterial pressure, heart rate, total dose of dobutamine, total dose of sodium nitroprusside, and need for fentanyl.
  
  
  CONCLUSIONS
  Data analysis from patients included in this study allows us to conclude that intravenous clonidine (2 μg/kg) was not able to reduce the mean pulmonary arterial pressure in patients with pulmonary hypertension in group 2 (pulmonary venous hypertension), undergoing heart surgery, or reduce or eliminate the need for intraoperative administration of dobutamine and sodium nitroprusside.
authors.affiliation: Hospital São Paulo, Universidade Federal de São Paulo, São Paulo, SP, Brazil; Hospital Beneficência Portuguesa, São Paulo, SP, Brazil. Electronic address: beneditobj@uol.com.br.
authors.forename: Benedito Barbosa
authors.initials: BB
authors.lastname: João
authors.affiliation: Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: José Luis Gomes
authors.initials: JL
authors.lastname: do Amaral
authors.affiliation: Hospital Beneficência Portuguesa, São Paulo, SP, Brazil.
authors.forename: Ronaldo Machado
authors.initials: RM
authors.lastname: Bueno
authors.affiliation: Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: David
authors.initials: D
authors.lastname: Ferez
authors.affiliation: Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: Luiz Fernando dos Reis
authors.initials: LF
authors.lastname: Falcão
authors.affiliation: Hospital São Paulo, Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: Marcelo Vaz
authors.initials: MV
authors.lastname: Perez
authors.affiliation: Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: Itamar Souza
authors.initials: IS
authors.lastname: de Oliveira-Júnior
mesh_terms: D000328:Adult; D000368:Aged; D062186:Arterial Pressure / Q000187:drug effects; D006348:Cardiac Surgical Procedures; D003000:Clonidine / Q000494:pharmacology / Q000627:therapeutic use*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000188:drug therapy* / Q000503:physiopathology; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged
chemical_list: D003000:Clonidine
keywords: Clonidine; Heart surgery; Pulmonary hypertension