title: Effects of acute bleeding followed by hydroxyethyl starch 130/0.4 or a crystalloid on propofol concentrations, cerebral oxygenation, and electroencephalographic and haemodynamic variables in pigs.
abstract: Bleeding changes the haemodynamics, compromising organ perfusion. In this study, the effects of bleeding followed by replacement with hydroxyethyl starch 130/0.4 (HES) or lactated Ringer's (LR) on cerebral oxygenation and electroencephalogram-derived parameters were investigated. Twelve young pigs under propofol-remifentanil anaesthesia were bled 30 mL/kg and, after a 20-minute waiting period, volume replacement was performed with HES (GHES; N = 6) or LR (GRL; N = 6). Bleeding caused a decrease of more than 50% in mean arterial pressure (P < 0.01) and a decrease in cerebral oximetry (P = 0.039), bispectral index, and electroencephalogram total power (P = 0.04 and P < 0.01, resp.), while propofol plasma concentrations increased (P < 0.01). Both solutions restored the haemodynamics and cerebral oxygenation similarly and were accompanied by an increase in electroencephalogram total power. No differences between groups were found. However, one hour after the end of the volume replacement, the cardiac output (P = 0.03) and the cerebral oxygenation (P = 0.008) decreased in the GLR and were significantly lower than in GHES (P = 0.02). Volume replacement with HES 130/0.4 was capable of maintaining the cardiac output and cerebral oxygenation during a longer period than LR and caused a decrease in the propofol plasma concentrations.
authors: Toxicology Department, REQUIMTE, Faculdade de Farmacia, Universidade do Porto, Rua de Jorge Viterbo Ferreira, No. 228, 4050-313 Porto, Portugal.
authors: Aura
authors: 0000-0002-2044-6320
authors: A
authors: Silva
authors: Universidad de Leon, Avenida Facultad de Veterinaria, No. 25, 24004 León, Spain.
authors: Ana Liza
authors: 0000-0001-6317-9237
authors: AL
authors: Ortiz
authors: Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), Animal Science Department, University of Tras-os-Montes and Alto Douro, Quinta de Prados, 5000-801 Vila Real, Portugal.
authors: Carlos
authors: C
authors: Venâncio
authors: Unidade Academica de Medicina Veterinária, Universidade Federal de Campina Grande, Patos, Rua Sinfrônio Nazaré, 1 Centro, 58800-240 Sousa, PB, Brazil.
authors: Almir P
authors: AP
authors: Souza
authors: Chemistry Department, Faculdade de Ciencias e Tecnologia, Universidade Nova de Lisboa, EQUIMTE/CBQF, Quinta da Torre, 2829-516 Caparica, Portugal.
authors: Luísa Maria
authors: LM
authors: Ferreira
authors: Chemistry Department, Faculdade de Ciencias e Tecnologia, Universidade Nova de Lisboa, EQUIMTE/CBQF, Quinta da Torre, 2829-516 Caparica, Portugal.
authors: Paula Sério
authors: PS
authors: Branco
authors: Toxicology Department, REQUIMTE, Faculdade de Farmacia, Universidade do Porto, Rua de Jorge Viterbo Ferreira, No. 228, 4050-313 Porto, Portugal.
authors: Paula Guedes
authors: PG
authors: de Pinho
authors: Anaesthesiology Department, Hospital Geral de Santo Antonio, 4099-001 Porto, Portugal.
authors: Pedro
authors: P
authors: Amorim
authors: Veterinary Sciences Research Center (CICV), Faculdade de Medicina Veterinaria, Universidade Lusófona de Humanidades e Tecnologias, Campo Grande 376, 1749-024 Lisboa, Portugal.
authors: David A
authors: DA
authors: Ferreira