Johan Persson

Clinical experience with minimal flow xenon anesthesia

Xenon is a more potent anesthetic than nitrous oxide, and gives more profound analgesia. This investigation was performed to assess the potential of xenon for becoming an anesthetic inspite of its high manufacturing cost. Seven ASA I—‐II patients undergoing cholecystectomy (n = 4), hernia repair (n = 2), or mammoplasty (n=l) were studied. Denitrogenation by 15–20 min of oxygen breathing under propofol anesthesia was followed by fentanyl–supplemented xenon anesthesia administered via an automatic minimal flow system which held the oxygen concentration at 30%. Xenon anesthesia lasted 76–228 min and 8–14 1 of xenon (ATPD) was used, of which 5.6–8.1 1 was expended during the first 15 min. Anesthesia appeared to be satisfactory, and the patients woke up rapidly after xenon was discontinued. The automatic system made minimal flow xenon anesthesia easy to administer, but nitrogen accumulation is still a problem. Assuming a xenon price of 10 US

Plasma volume expansion and transcapillary fluid exchange in skeletal muscle of albumin, dextran, gelatin, hydroxyethyl starch, and saline after trauma in the cat*

per litre, the average cost for xenon was about 65 US

Patients with sepsis exhibit increased mitochondrial respiratory capacity in peripheral blood immune cells

for the first 15 min and then about 25 USS for each subsequent hour of anesthesia.

Importance of the Infusion Rate for the Plasma Expanding Effect of 5% Albumin, 6% HES 130/0.4, 4% Gelatin, and 0.9% NaCl in the Septic Rat.

Objective:To compare 5% albumin, 6% dextran 70, 3.5% gelatin, 6% hydroxyethyl starch 130/0.4, and saline regarding their plasma volume expanding effect after a surgical skeletal muscle trauma and their simultaneous effects on transvascular fluid exchange in skeletal muscle. Design:Controlled, prospective, randomized laboratory study. Setting:University research laboratory. Subjects:Thirty-six adult cats. Interventions:Systemic arterial pressure and tissue volume variations of and blood flow to a surgically isolated and autoperfused calf muscle placed in a plethysmograph were recorded. Arterial and venous pressures to the muscle were kept constant. After preparation, plasma volumes were determined by a 125I albumin tracer technique just before and 3 hrs after a bolus infusion of the plasma expander (25 mL/kg). Measurements and Main Results:Plasma volume was 20.9 ± 2.9 mL/kg (n = 36) just before infusion of the plasma expander (normal plasma volume for the cat is 34–37 mL/kg). The remaining volume expansion of the infusion after 3 hrs was 6.8 mL/kg for albumin, 11.2 mL/kg for dextran, 1.8 mL/kg for gelatin, 2.2 mL/kg for hydroxyethyl starch, and 0.9 mL/kg for saline. Plasma volume decreased by 1.1 mL/kg when no solution was given (n = 6 per group). Colloid osmotic pressure was better preserved with dextran and albumin than with the other solutions. Albumin and dextran reduced muscle volume by absorption after 3 hrs, whereas the initial absorption turned to net filtration in the gelatin and hydroxyethyl starch groups. Saline infusion increased muscle volume by filtration for about 20 mins, followed by an approximately constant volume. Conclusion:The relatively poor plasma expansion for all solutions analyzed can most likely be explained by increased transcapillary leakage due to increased microvascular permeability following trauma. Under such circumstances, for equal volumes, plasma expansion was better preserved with 6% dextran 70 than with 5% albumin, which was better than 3.5% gelatin, 6% hydroxyethyl starch 130/0.4, and saline.

Thoracic epidural anesthesia and epidural hematoma.

IntroductionIn sepsis, mitochondria have been associated with both initial dysfunction and subsequent upregulation (biogenesis). However, the evolvement of mitochondrial function in sepsis over time is largely unknown, and we therefore investigated mitochondrial respiration in peripheral blood immune cells (PBICs) in sepsis patients during the first week after admission to the intensive care unit (ICU).MethodsPBICs from 20 patients with severe sepsis or septic shock were analyzed with high-resolution respirometry 3 times after admission to the ICU (within 48 hours, days 3 to 4 and days 6 to 7). Mitochondrial DNA (mtDNA), cytochrome c (Cyt c), and citrate synthase (CS) were measured as indicators of cellular mitochondrial content.ResultsIn intact PBICs with endogenous substrates, a gradual increase in cellular respiration reached 173% of controls after 1 week (P = 0.001). In permeabilized cells, respiration using substrates of complex I, II, and IV were significantly increased days 1 to 2, reaching 137%, 130%, and 173% of controls, respectively. In parallel, higher levels of CS activity, mtDNA, and Cyt c content in PBICs (211%, 243%, and 331% of controls for the respective indicators were found at days 6 to 7; P < 0.0001). No differences in respiratory capacities were noted between survivors and nonsurvivors at any of the time points measured.ConclusionsPBICs from patients with sepsis displayed higher mitochondrial respiratory capacities compared with controls, due to an increased mitochondrial content, as indicated by increased mitochondrial DNA, protein content, and enzyme activity. The results argue against mitochondrial respiratory dysfunction in this type of cells in sepsis.

The Effect and Duration of Prophylactic Platelet Transfusions Before Insertion of a Central Venous Catheter in Patients with Bone Marrow Failure Evaluated with Point-of-Care Methods and Flow Cytometry

Objectives:To compare the plasma volume (PV) expanding effect of a fast infusion rate with that of a slow infusion rate of a fixed volume of 5% albumin, of the synthetic colloids, 6% hydroxyethyl starch 130/0.4 and 4% gelatin, and of 0.9% NaCl in a rat sepsis model and to compare the plasma-expanding effect among these fluids. Design:Prospective, randomized animal study. Setting:University hospital laboratory. Subjects:One hundred and twelve adult male rats. Interventions:Sepsis was induced by cecal ligation and incision followed by closure of the abdomen. After 3 hrs, an infusion of the PV expander under study was started at a volume of 12mL/kg for the colloids and of 48mL/kg for 0.9% NaCl, either for 15 mins or for 3 hrs. A control group underwent the same experimental procedure but no fluid was given. Measurements and Main Results:Three hours after start of the infusion (end of experiment), the plasma-expanding effect was better with a slow than a fast infusion rate for the colloids, especially albumin, but the NaCl groups did not differ significantly from the control group. The PV for the control group was 28.7±3mL/kg. In the slow and the fast infusion groups, it was 38.9±4.3 and 32.6±4.2mL/kg for albumin (p < 0.001), 32.9±4.3 and 29.5±4.4mL/kg for hydroxyethyl starch 130/0.4 (p < 0.05), 31.8±3.9 and 28.2±4.1mL/kg for gelatin (p < 0.05), and 31.8±5.3 and 30.7±6.6mL/kg for NaCl (n.s), respectively. Conclusions:The study showed that the PV expansion by a colloid was greater when given at a slow than at a fast infusion rate, an effect more pronounced for albumin. This difference was not seen for NaCl. The PV-expanding effect was poor for NaCl and better for albumin than for the other colloids.

Effect of pancreatic phospholipase A2 and gastric lipase on the action of pancreatic carboxyl ester lipase against lipid substrates in vitro

This report involves a 74‐year‐old‐male who developed a thoracic epidural hematoma with paraparesis on the second postoperative day in conjunction with thoracic epidural anesthesia established before surgery for acute abdominal aortic dissection.

Comparison of the plasma volume-expanding effects of 6% dextran 70, 5% albumin, and 6% HES 130/0.4 after hemorrhage in the guinea pig.

BACKGROUND:Patients with bone marrow failure and severe thrombocytopenia are frequently given prophylactic platelet transfusion before interventions. The clinical effects of such transfusions, however, are poorly defined. We performed a prospective observational study on patients with bone marrow failure scheduled for prophylactic platelet transfusion before the insertion of a central venous catheter. The objectives were to evaluate the effect and duration of prophylactic platelet transfusions on central venous catheter insertion in thrombocytopenic patients with bone marrow failure. METHODS:Thirty-nine adult patients with bone marrow failure and platelet counts below 50 × 109/L were consecutively enrolled before prophylactic platelet transfusion for subclavian central venous catheter insertion. Blood samples were drawn from the patients before platelet transfusion, 1 hour, and 4 hours after completion of the transfusion. The coagulation profile was assessed by conventional hematological tests, thromboelastometry (ROTEM®) assays (EXTEM® and FIBTEM®), multiple electrode aggregometry (Multiplate®) assays including adenosine diphosphate, collagen, and thrombin receptor agonist peptide, and by flow cytometry for the platelet expression of P-selectin (CD62P) and activated glycoprotein IIb–IIIa (PAC-1). Bleeding complications were classified with a 5-grade scale, according to the Common Terminology Criteria for Adverse Events. RESULTS:Seventeen women and 22 men were included in the study. Platelet count was increased from 24 × 109/L (18–32) before to 42 × 109/L (31–50) 1 hour after transfusion (P < 0.0001) and was not significantly different 4 hours after transfusion (40 × 109/L (29–50), P = 0.047). Maximal clot firmness EXTEM was increased from 38 mm (32–45) before to 46 mm (41–52) 1 hour after transfusion (P < 0.0001) and did not change 4 hours after transfusion. Clotting time EXTEM was decreased from 58.5 seconds (50–78) beforehand to 53 seconds (45–61) 1 hour after transfusion (P = 0.0006) and was not significantly different 4 hours after transfusion (57 seconds (52–70, P = 0.025). FIBTEM results were all unchanged after transfusion. All Multiplate analyses were significantly increased after 1 hour and were not diminished 4 hours after transfusion. Four grade 1 bleeding episodes occurred, but no grade 2 to 5 bleeding could be detected. Flow cytometry analyses showed mixed results with no overall trend. CONCLUSIONS:Prophylactic platelet transfusions in thrombocytopenic patients with bone marrow failure improve hemostatic parameters on ROTEM and Multiplate by increasing the number of platelets, and not through enhancement of platelet function. Improved clotting parameters on ROTEM and platelet aggregation on Multiplate appear to persist between 1 and 4 hours after transfusion.

Nitric oxide and prostacyclin play a role in the regulation of microvascular protein and hydraulic permeability in cat skeletal muscle.

Preincubation of a triolein/phospholipid/cholesteryl oleate-emulsion in vitro with either pancreatic phospholipase A2 (PLA2) or gastric lipase (GL) resulted in hydrolysis (measured by pH-stat-titration) of cholesteryl [3H]oleate only after human pancreatic carboxyl ester lipase (CEL) was added to the system. No appreciable hydrolysis was observed when CEL was added alone. Consequently, a concerted action either of PLA2 and CEL or of GL and CEL made the substrate cholesteryl oleate available for hydrolysis by CEL. This was the case when cholesteryl oleate was solubilised in a phospholipid-stabilised triglyceride emulsion, which is the physico-chemical form in which the major part of dietary cholesteryl esters are presented to the gastro-intestinal tract of man.

Endogenous Nitric Oxide Reduces Microvascular Permeability and Tissue Oedema during Exercise in Cat Skeletal Muscle

BACKGROUND We still lack comparing data of the plasma volume (PV)-expanding effect of the most commonly used colloids including dextran 70. This study compares the PV-expanding effects of 6% dextran 70, 5% albumin, and 6% hydroxyethylstarch (HES) 130/0.4 after a standardized hemorrhage. METHODS The prospective and randomized study on 33 anesthetized adult male guinea pigs involved three groups (n = 11 each); the dextran group, the albumin group, and the HES group. The left carotis artery was cannulated for blood pressure measurements and blood samples, and the right jugular vein was cannulated for infusions. After hemorrhage of 20 mL/kg for 8 minutes, the animals were transfused with 20 mL/kg of the colloid for 10 minutes. PV was determined with a I-albumin tracer dilution technique at baseline and 3 hours after the colloid infusion. The PV just after hemorrhage was calculated as the baseline value minus bled PV. Blood gases were measured at baseline, after hemorrhage, just after the colloid infusion and at the end of the experiment. RESULTS The increase in PV 3 hours after the colloid infusion, including the 20 mL infused, was 36.3 mL/kg +/- 2.3 mL/kg in the dextran group, 26.4 mL/kg +/- 4.7 mL/kg in the albumin group, and 17.6 mL/kg +/- 3.5 mL/kg in the HES group. At the end of the experiment, hematocrit was lower in the dextran group than in the albumin and the HES groups. Urine production was higher in the HES group than in the dextran and the albumin groups. CONCLUSION After hemorrhage, the PV-expanding capacity of 6% dextran 70 was better than that of 5% albumin, which was in turn better than that of HES 130/0.4 given in equal volumes.