RESUMO
OBJECTIVES: The purpose of this study was to determine the effects of hypothermia and normothermia on the isolated human saphenous vein (SV) and internal mammary artery (IMA) responses to dexmedetomidine. METHODS: The response of human IMA and SV strips with (E+) and without (E-) endothelium subjected to cumulative concentrations of (10-9, 0-6 M) dexmedetomidine were recorded at 37 °C and at 28 °C. OnE-way ANOVA was used for analysis. A p < 0.05 was considered significant. RESULTS: At 37ËC dexmedetomidine resulted in similar significant concentration-dependent contractions in both E+ and E- SV strips (p < 0.05). At 37 °C dexmedetomidine resulted in significant concentration-dependent contractions in E+ IMA strips, these contractions were significantly lower at all concentrations of dexmedetomidine in E- compared to E+ IMA strips (p < 0.05). When results between similar groups of SV and IMA strips were compared, the contractions were significantly higher in the IMA strips in E+ and E- at 37 °C and also E- 28 °C groups compared to SV (p < 0.05). CONCLUSION: In conclusion, dexmedetomidine causes in vitro vasoconstriction in human IMA and SV grafts. These contractions are greater in IMA compared to SV grafts. Endothelium-derived pathways are possibly involved in the contractile responses of IMA. Moderate hypothermia augments vasoconstriction in SV grafts (Fig. 3, Ref. 27).
Assuntos
Agonistas de Receptores Adrenérgicos alfa 2 , Dexmedetomidina , Hipotermia , Artéria Torácica Interna , Veia Safena , Agonistas de Receptores Adrenérgicos alfa 2/farmacologia , Dexmedetomidina/farmacologia , Humanos , Artéria Torácica Interna/diagnóstico por imagem , Veia Safena/transplante , VasoconstriçãoRESUMO
OBJECTIVE: We aimed to investigate the vasoactive effects of dexmedetomidine on isolated human umbilical arteries and possible mechanisms involved. METHODS: Human umbilical artery strips were suspended in Krebs-Henseleit solution and dose-response curves were obtained for cumulative dexmedetomidine before and after incubation with different agents; propranolol, atropine, yohimbine, prazosin, indomethacin, verapamil. Effects of calcium on cumulative dexmedetomidine-induced contractions were also studied. RESULTS: Cumulative dexmedetomidine resulted in dose dependent contraction responses. Incubation with propranolol (Emax: 93.3 ± 3.26 %), atropine (Emax: 92.0 ± 6.54 %), or indomethacin (Emax: 94.25 ± 2.62 %), did not attenuate dexmedetomidine-elicited contractions (p > 0.05). There were significant decreases in the contraction responses of cumulative dexmedetomidine with yohimbine (Emax: 12.1 ± 11.9 %), prazosin (Emax: 28.8 ± 4.6 %) and verapamil (Emax: 11.2 ± 13.6 %) (p < 0.05). In Ca+2 free medium contraction responses to cumulative dexmedetomidine was insignificant (Emax: 5.20 ± 3.42 %). Addition of cumulative calcium to the Ca+2 free medium resulted in concentration dependent increase in contractions (Emax: 64.83 ± 37.7 %) (p < 0.05). CONCLUSION: Dexmedetomidine induces vasoconstriction in endothelial-free umbilical arteries via both, α1- and α2-adrenergic receptors and also extracellular Ca+2 concentrations play a major role. ß-adrenergic receptors, muscarinic cholinergic receptors, and inhibition of cyclooxygenase enzyme are not involved in this vasoconstriction (Fig. 3, Ref. 36).
Assuntos
Analgésicos não Narcóticos , Dexmedetomidina , Vasoconstrição , Analgésicos não Narcóticos/farmacologia , Cálcio , Dexmedetomidina/farmacologia , Humanos , Técnicas In Vitro , Contração Muscular/efeitos dos fármacos , Músculo Liso Vascular , Artérias Umbilicais , Vasoconstrição/efeitos dos fármacosRESUMO
Pericardial mesothelioma is a rare and highly aggressive and lethal cardiac tumour. A 25-year-old male patient who was complaining of fever, night sweats, shortness of breath and palpitations after an upper respiratory system infection was admitted in May 2008. He had a history of 12 years exposure to asbestos. When the patient was referred to our hospital in June 2008, his complaints of palpitations and shortness of breath were continuing. He had oedema of legs and a venous swelling on his neck. The echocardiography showed pericardial effusion and pericardial thickening which were also found on the CT. Through median sternotomy a pericardectomy and tumor resection were performed. Histological and immunohistochemical findings lead to the diagnosis of malignant pericardial mesothelioma. In conclusion, there is still not a radical therapy for primary pericardial mesothelioma. Surgery is done to prevent cardiac tamponade and relieves constriction (Fig. 1, Ref. 12).
Assuntos
Tamponamento Cardíaco/etiologia , Neoplasias Cardíacas/diagnóstico , Mesotelioma/diagnóstico , Pericárdio , Adulto , Neoplasias Cardíacas/complicações , Humanos , Masculino , Mesotelioma/complicações , Derrame Pericárdico/etiologiaRESUMO
Aneurysmal dilatation of coronary arteries is characterized by abnormal dilatation of a localized or diffuse segment of the coronary arterial tree. Left main coronary artery aneurysms are rare coronary anatomic abnormalities. They rarely involve the left main coronary artery. Different strategies have been adopted, where the coronary artery aneurysms have been left as such, resected partially, isolated, reconstructed, ligated with a simultaneous bypass with internal mammary artery, or treated with vein grafts. We report a case of a successful ligation of aneurysm of the left main coronary artery and three simultaneous coronary artery bypass procedures (Fig. 1, Ref. 15).
Assuntos
Aneurisma Coronário/cirurgia , Aneurisma Coronário/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , RadiografiaRESUMO
OBJECTIVE: Postoperative new-onset atrial fibrillation (POAF) commonly occurs after coronary artery bypass graft (CABG) surgery. This study aimed to determine the utility of the preoperative netrin-1 and galectin-3 levels for predicting POAF following CABG surgery, as well as that of postoperative serial measurement for assessing these markers' patterns of expression. PATIENTS AND METHODS: This prospective cohort study included 50 patients that underwent CABG surgery. The plasma netrin-1 and galectin-3 levels were measured via enzyme-linked immunosorbent assay (ELISA) before surgery (baseline) and at 6, 12, and 24 h after surgery. The patients were divided into two groups according to the occurrence of POAF; the POAF (+) group and the POAF (-) group. RESULTS: In total, 26 patients developed POAF, whereas 24 remained in sinus rhythm. Baseline galectin-3 levels were higher in the POAF (+) group than in the POAF (-) group (30.7 ± 10.1 pg mL-1 and 15.7 ± 3.6 pg mL-1, respectively). The post-CABG surgery galectin-3 level increased in both the POAF (+) and POAF (-) groups at 6 h (46.2 ± 26.3 pg mL-1 and 24.9 ± 5.9 pg mL-1, respectively), 12 h (45.2 ± 24.1 pg mL-1 and 26.6 ± 9.3 pg mL-1, respectively), and 24 h (54.2 ± 33.5 pg mL-1and 28.6 ± 7.7 pg mL-1, respectively). The plasma netrin-1 level did not differ between groups at baseline or at 6, 12, and 24 h post CABG surgery. CONCLUSIONS: Whereas netrin-1 does not appear to have any utility as a marker for the development of POAF in CABG surgery patients, the plasma galectin-3 level has high specificity and sensitivity for predicting POAF following CABG surgery and could be considered a marker for predicting POAF.
Assuntos
Fibrilação Atrial , Ponte de Artéria Coronária , Galectina 3 , Humanos , Fibrilação Atrial/sangue , Fibrilação Atrial/etiologia , Fibrilação Atrial/genética , Ponte de Artéria Coronária/efeitos adversos , Galectina 3/genética , Galectina 3/metabolismo , Netrina-1/genética , Netrina-1/metabolismo , Complicações Pós-Operatórias , Estudos Prospectivos , Fatores de RiscoRESUMO
BACKGROUND: Post-anaesthetic shivering is one of the most common complications, occurring in 5-65% of patients recovering from general anaesthesia and 33% of patients receiving epidural anaesthesia. Our objective was to investigate the efficacy of intraoperative dexmedetomidine infusion on postoperative shivering. METHODS: Ninety female patients, ASA I-II, 35-60 yr old, scheduled for elective total abdominal hysterectomy with or without bilateral salpingo-oophorectomy were randomized into two groups. After endotracheal intubation one group received normal saline infusion and the other received dexmedetomidine as a loading dose of 1 microg kg(-1) for 10 min followed by a maintenance infusion of 0.4 microg kg(-1) h(-1). In the recovery room, pain was assessed using a 100 mm visual analogue scale and those patients who had a pain score of more than 40 mm were administered 1 mg kg(-1) intramuscular diclofenac sodium. Patients with shivering grades more than 2 were administered 25 mg intravenous meperidine. Patients were protected with passive insulation covers. RESULTS: Post-anaesthetic shivering was observed in 21 patients in the saline group and in seven patients in the dexmedetomidine group (P = 0.001). Shivering occurred more often in the saline group. The Ramsay Sedation Scores were higher in the dexmedetomidine group during the first postoperative hour. Pain scores were higher in the saline group for 30 min after the operation. The need for intraoperative atropine was higher in the dexmedetomidine group. Intraoperative fentanyl use was higher in the saline group. Perioperative tympanic temperatures were not different between the groups whereas postoperative measurements were lower in the dexmedetomidine group (P < 0.05). CONCLUSION: Intraoperative dexmedetomidine infusion may be effective in the prevention of post-anaesthetic shivering.
Assuntos
Analgésicos não Narcóticos/administração & dosagem , Anestesia Geral/efeitos adversos , Dexmedetomidina/administração & dosagem , Histerectomia/efeitos adversos , Complicações Pós-Operatórias/prevenção & controle , Estremecimento/efeitos dos fármacos , Adulto , Analgésicos Opioides/uso terapêutico , Análise de Variância , Período de Recuperação da Anestesia , Temperatura Corporal/efeitos dos fármacos , Procedimentos Cirúrgicos Eletivos , Feminino , Fentanila/uso terapêutico , Humanos , Histerectomia/métodos , Infusões Intravenosas , Pessoa de Meia-Idade , Medição da Dor/métodosRESUMO
BACKGROUND: The main metabolic pathway for defluorination of sevoflurane in the liver produces inorganic fluoride (Fl). The metabolism and effect of sevoflurane on the kidney is not clear during anhepatic phase in liver transplantation. The goal of the present study was to investigate the metabolism and renal effect of sevoflurane by measuring plasma and urine inorganic fluoride, urinary N-acetyl-glucosaminidase (NAG), and plasma creatinine levels in patients undergoing liver transplantations. METHODS: After institutional approval and informed consent, we studied nine cases of orthotopic liver transplantation after anesthesia was induced with 5 mg . kg(-1) thiopental, 1 mug . kg(-1) fentanyl intravenously, the trachea was intubated after vecuronium bromide 0.1 mg . kg(-1). Anesthesia was maintained with sevoflurane (2%), O(2), and N(2)O at a total gas flow of 6 L . min(-1) using a semiclosed circle system with a sodalime canister. Blood and urine samples were obtained to measure plasma and urine fluoride concentrations and urinary NAG excretions before induction (P0), hourly during resection (P1, P2, P3), every 15 minutes during anhepatic phase (A1, A2, A3), hourly after reperfusion (neohepatic phase) (N1, N2, N3), and postoperative first hour (Po1). Preoperative (T0) and postoperative day 1 (T1), 3 (T3), 7 (T7) plasma blood urea nitrogen (BUN) and creatinine (Cr) levels were also recorded. RESULTS: Mean duration of surgery was 9:06 +/- 0:09 hours. Mean inorganic fluoride concentrations in plasma were in the range of 0.71 +/- 0.30 to 28.73 +/- 3.31 mumole . L(-1). In P3, N1, N2, N3, increases in plasma inorganic fluoride concentrations were significant (P < .05) and reached a peak value at Po1. The mean urine inorganic fluoride concentrations were 12.49 +/- 2.04 to 256.7 +/- 49.62 mumole . L(-1). In A2, A3, N1, N2, and N3, mean urine inorganic fluoride concentrations were significantly increased (P < .05) and the peak value was observed at Po1. Mean NAG concentrations in urine varied (5.6 +/- 1.6 IU . L(-1) to 12.5 +/- 1.14 IU . L(-1)) and peak level was observed at 30 minutes of the anhepatic phase (A2), which did not exceed the normal values for urine NAG levels (1.5 to 6.1 U . L(-1)). No impairment was observed in serum BUN and creatinine levels at any time. While there was only a slight increase in NAG during anhepatic phase, there was no change in plasma F1. CONCLUSIONS: Sevoflurane seemed to have minimal effect on kidney functions of BUN and Cr levels during liver transplantation. Although urine F1 and NAG levels increased during the anhepatic phase plasma F1, BUN, and Cr levels did not, suggesting that renal F1 production may occur in the absence of hepatic function. The renal effect of sevoflurane in chronic liver disease is controversial and must be investigated in further studies.
Assuntos
Anestésicos Inalatórios/farmacocinética , Transplante de Fígado/fisiologia , Éteres Metílicos/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Acetilglucosamina/urina , Adolescente , Adulto , Anestesia/métodos , Biotransformação , Criança , Fluoretos/sangue , Fluoretos/urina , Humanos , Transplante de Fígado/métodos , Pessoa de Meia-Idade , Segurança , SevofluranoRESUMO
OBJECTIVE: Gynaecological oncological surgery (GOS) includes a wide variety of surgical procedures and postoperative pain is a major concern. This study compared the impact of intrathecal morphine (ITM) plus patient-controlled analgesia (PCA) with PCA alone on morphine consumption, pain relief and patient satisfaction after GOS. METHODS: Sixty women undergoing GOS under general anaesthesia were randomized to receive either 0.3 mg ITM or placebo. On arrival at the postanaesthesia care unit each patient received a morphine PCA pump. The three primary outcome measures were pain, patient satisfaction scores evaluated using a 100-mm visual analogue scale and cumulative PCA morphine consumption. RESULTS: No significant differences were observed in the demographic data. Cumulative PCA morphine consumption was significantly lower in the ITM group compared with the control group. Fatigue scores were lower in the ITM group compared with the control group but did not reach statistical significance. Pain, sedation and patient satisfaction scores, and the rate of side-effects were similar for the two groups. CONCLUSIONS: Administering ITM in GOS could improve postoperative analgesia and reduce morphine consumption without serious side-effects.