title: Vasopressor administration during liver transplant surgery and its effect on endotracheal reintubation rate in the postoperative period: a prospective, randomized, double-blind, placebo-controlled trial.
abstract: BACKGROUND
  End-stage liver disease (ESLD) is associated with a low systemic vascular resistance due to peripheral vasodilatation. This phenomenon is aggravated by general anesthesia (GA) administered during liver transplantation, resulting in precipitous decreases in blood pressure. The excessive amounts (>3 mL/1 mL blood loss) of IV fluid administered to maintain hemodynamic stability during surgery promotes a fluid shift in the lung, which may lead to hypoxia in the immediate postoperative period. This pathophysiologic state may necessitate endotracheal reintubation and mechanical ventilation of the lungs, thus exposing the patient to a risk for morbidities related to laryngoscopy and endotracheal intubation, including deleterious cardiovascular responses to laryngoscopy, endotracheal damage due to laryngoscopic instrumentation, alteration in pulmonary mechanics secondary to controlled mechanical ventilation of the lungs, and delayed recovery associated with the sedation needed to perform these maneuvers.
  
  
  OBJECTIVE
  The aim of this study was to determine whether the use of a vasopressor to antagonize the vasodilatory effect of GA would reduce the amount of IV fluids administered during liver transplantation, and whether the subsequent amelioration of fluid shift in the postoperative period would reduce the need for ventilatory support and endotracheal reintubation.
  
  
  METHODS
  This prospective, randomized, double-blind, placebo-controlled study was conducted at the University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey. Patients aged > or =18 years scheduled to undergo orthotopic liver transplantation for ESLD were enrolled. The effect of use of an adjuvant vasopressor, together with controlled fluid administration (ie, the volume of IV fluid needed to maintain hemodynamic parameters at > or =80% of preoperative levels) (vasopressor group), was compared with that of fluid administration only (placebo group). We determined various postoperative outcome measures, primarily the amount of fluid administered and the need for endotracheal reintubation.
  
  
  RESULTS
  Sixty-five patients were enrolled (44 men, 21 women; vasopressor, 33 patients; placebo, 32 patients). Sex distribution showed 19 men and 14 women in the vasopressor group and 25 men and 7 women in the placebo group (both, P < 0.05). The 2 treatment groups were statistically similar with regard to the rest of the baseline demographic and clinical characteristics and duration of surgery. The vasopressor group had a significantly lower prevalence of endotracheal reintubation compared with the placebo group (RR, 1:6; P < 0.05). The other postoperative parameters were statistically similar between the 2 groups.
  
  
  CONCLUSIONS
  In this study of adults undergoing orthotopic liver transplantation for ESLD, use of an adjuvant vasopressor, together with controlled fluid administration, to maintain a stable hemodynamic status during GA reduced the need for endotracheal reintubation and its associated morbidities in the postoperative period compared with placebo.
authors.affiliation: Department of Anesthesiology, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey 07103, USA. Ponnudrn@umdnj.edu
authors.forename: Rex N
authors.initials: RN
authors.lastname: Ponnudurai
authors.forename: Baburao
authors.initials: B
authors.lastname: Koneru
authors.forename: Shuaib A
authors.initials: SA
authors.lastname: Akhtar
authors.forename: Ronald H
authors.initials: RH
authors.lastname: Wachsberg
authors.forename: Adrian
authors.initials: A
authors.lastname: Fisher
authors.forename: Dorian J
authors.initials: DJ
authors.lastname: Wilson
authors.forename: Andrew N
authors.initials: AN
authors.lastname: de la Torre
mesh_terms: D000768:Anesthesia, General / Q000009:adverse effects; D004311:Double-Blind Method; D005260:Female; D005440:Fluid Therapy; D006801:Humans; D007442:Intubation, Intratracheal; D016031:Liver Transplantation; D008297:Male; D008875:Middle Aged; D009638:Norepinephrine / Q000627:therapeutic use*; D011184:Postoperative Period; D012121:Respiration, Artificial; D014662:Vasoconstrictor Agents / Q000627:therapeutic use*; D014664:Vasodilation / Q000187:drug effects
chemical_list: D014662:Vasoconstrictor Agents; D009638:Norepinephrine