Hepatic blood flow in humans during isoflurane-N2O and halothane-N2O anesthesia.

Hepatic blood flow (HBF) (assessed by plasma clearance and hepatic extraction of indocyanine green), cardiac index, and hepatic venous oxygen saturation were measured in patients before and after induction of anesthesia with thiopental, fentanyl, and N2O, and again during halothane (1 MAC)-N2O (n = 5) or isoflurane (1 MAC)-N2O (n = 6) anesthesia before the start of surgery. Induction of anesthesia decreased HBF and cardiac index. Before administration of volatile anesthetics, both groups had similar values of HBF, cardiac index, and hepatic venous oxygen saturation. During anesthesia cardiac index remained stable in both groups, whereas HBF increased significantly with isoflurane but did not change significantly with halothane. Hepatic venous oxygen saturation was also significantly greater during isoflurane than during halothane anesthesia. We conclude that isoflurane increases HBF in anesthetized patients and is associated with a higher hepatic venous oxygen saturation than is halothane.

Effects of ketamine, halothane, enflurane, and isoflurane on systemic and splanchnic hemodynamics in normovolemic and hypovolemic cirrhotic rats.

The effects of ketamine, halothane, enflurane, and isoflurane on systemic and splanchnic hemodynamics in cirrhotic rats that were either normovolemic or hypovolemic following hemorrhage were characterized. Rats received at random either ketamine (30 mg/kg iv, 1.5 mg.kg-1.min-1 iv), halothane, enflurane, or isoflurane (1 MAC). Conscious rats were considered the control group. Four weeks before hemodynamic studies bile duct ligation was performed in all rats to induce cirrhosis. Hemodynamic measurements were performed using the radioactive microsphere method 1 h after the onset of anesthesia and 30 min after hemorrhage. Anesthetized rat lungs were mechanically ventilated with room air. Before hemorrhage cardiac index was higher in conscious rats and in rats receiving isoflurane than in the other groups (P less than 0.001). Hepatic arterial blood flow was similar in conscious rats and in those receiving isoflurane or halothane and was higher than in those receiving ketamine or enflurane. The lowest splanchnic and portal venous tributary blood flows were observed in rats receiving enflurane. After hemorrhage cardiac index was significantly less than before hemorrhage in all groups, except in rats receiving enflurane. After hemorrhage portal venous tributary blood flow decreased significantly in all groups except in enflurane group. During halothane and enflurane anesthesia hepatic arterial blood flow and hepatic arterial fraction of cardiac output decreased (P less than 0.01) and they were maintained in the other groups. After hemorrhage hepatic arterial fraction of cardiac output in conscious rats was higher than in those receiving ketamine, halothane, or enflurane (P less than 0.05) and was similar to those receiving isoflurane.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparative effects of halothane and isoflurane anesthesia on the ultrastructure of human hepatic cells.

The effects of halothane and isoflurane on the ultrastructure of the liver cells in adult patients with normal liver-function tests were compared. After induction of anesthesia with thiopental, fentanyl, and pancuronium, 18 patients were randomly divided into three groups of six each. Anesthesia was maintained with droperidol (droperidol group), with halothane (1.7 MAC, halothane group), or with isoflurane (1.7 MAC, isoflurane group). During the surgical procedure, 1 hr after the induction, a liver biopsy was performed in each patient and processed for light and electron microscopy. All biopsies were normal on light microscopy. On electron microscopy, no mitochondrial abnormalities were found. In all three groups, irregular nuclear membranes, dilation of the rough endoplasmic reticulum, and vesiculation of the smooth endoplasmic reticulum were seen, without any significant differences between the groups. There were significantly more lysosomes in the hepatocytes of patients receiving halothane than in the hepatocytes of patients receiving isoflurane or droperidol. This study shows that halothane can induce ultrastructure abnormalities very early after the beginning of its administration while, under the same conditions, isoflurane does not.

[Postoperative analgesia: epidural injection of dexamethasone sodium phosphate]. / Analgésie postopératoire: injection péridurale de phosphate sodique de dexaméthasone.

Epidural administration of steroids has been suggested for the prevention of postoperative epidural fibrosis after lumbar lamino-arthrectomy. In order to assess the efficacy of this technique on pain occurring after such surgery, the demand of pentazocine during the first 24 postoperative hours was studied in 39 patients randomly assigned to two groups. Pain intensity was assessed by a five-point verbal scale (0: none; 1: poor; 2: moderate; 3: severe; 4: very severe) at five intervals (0-4, 5-8, 9-12, 13-16 and 17-24 h). The patients in group T (n = 20) did not receive any steroid, whereas those in group C (n = 19) were given, just after the end of surgery, a single dose of dexamethasone (4 mg) via an epidural lumbar catheter previously inserted by the surgeon. In group T, 18 patients required one or several intramuscular injections of pentazocine, whereas only three patients of group C (p less than 0.001) did so. Patients in group T expressed more severe pain (4 moderate, 12 severe, 3 unbearable) than those patients who had received steroids (1 moderate, 1 severe, 1 unbearable). As a consequence, they requested more pain killer (30 injections vs 8 injections, respectively; p less than 0.001) and sooner than patients of the steroid group (8 h vs 12 h; p less than 0.05). It was concluded that epidural administration of dexamethasone was helpful in preventing postoperative pain after lumbar lamino-arthrectomy.

[Clinical study of massive transfusions (108 cases)]. / Etude clinique des transfusions massives (108 cas).

Amongst 108 surgical patients receiving massive transfusions, 60 died. Study of the aetiology of the haemorrhage, the circumstances of the transfusion, and the role of massive transfusions in the transmission of infectious diseases, disturbances in haemostasis, immunological, respiratory and metabolic complications led to the determination of certain simple criteria of gravity which may restrict their use:age over 60 years; the number of units used, if it exceeds 30; the existence of cirrhosis, of an acute lesion as the source of bleeding, or of peroperative haemorrhage. By contrast, the transmission of hepatitis, coagulation disturbances, immediate or delayed incompatibility accidents and variations in pH, blood potassium and calcium levels and arterial pO2 had little influence on mortality.