ABSTRACT
PURPOSE: We evaluated the feasibility and robustness of three methods for propofol-to-bispectral index (BIS) post-operative intensive care sedation, a manually-adapted target controlled infusion protocol (HUMAN), a computer-controlled predictive control strategy (EPSAC) and a computer-controlled Bayesian rule-based optimized control strategy (BAYES). METHODS: Thirty-six patients undergoing short lasting sedation following cardiac surgery were included to receive propofol to maintain a BIS between 40 and 60. Robustness of control for all groups was analysed using prediction error and spectrographic analysis. RESULTS: Although similar time courses of measured BIS were obtained in all groups, a higher median propofol effect-site concentration (CePROP) was required in the HUMAN group compared to the BAYES and EPSAC groups. The time course analysis of the remifentanil effect-site concentration (CeREMI) revealed a significant increase in CeREMI in the EPSAC group compared to BAYES and HUMAN during the case. Although similar bias and divergence in control was found in all groups, larger control inaccuracy was observed in HUMAN versus EPSAC and BAYES. Spectrographic analysis of the system behavior shows that BAYES covers the largest spectrum of frequencies, followed by EPSAC and HUMAN. CONCLUSIONS: Both computer-based control systems are feasible to be used during ICU sedation with overall tighter control than HUMAN and even with lower required CePROP. EPSAC control required higher CeREMI than BAYES or HUMAN to maintain stable control. Clinical trial number: NCT00735631.
Subject(s)
Critical Care/methods , Deep Sedation/methods , Monitoring, Physiologic/methods , Propofol/administration & dosage , Aged , Algorithms , Anesthesia, Intravenous/methods , Anesthetics, Intravenous/therapeutic use , Bayes Theorem , Electroencephalography , Female , Humans , Infusions, Intravenous , Intensive Care Units , Male , Middle Aged , Pilot Projects , Postoperative Period , Reproducibility of Results , Signal Processing, Computer-Assisted , SoftwareABSTRACT
PURPOSE: The use of glue as mesh fixation in laparoscopic ventral hernia repair (LVHR) significantly reduces fixation associated morbidity. This experiment evaluates the intraperitoneal use of synthetic glue as single mesh fixation. METHODS: A total of 21 sheep were operated using a hernia model with two fascial defects of 2 cm(2) at the linea alba. One week later two polypropylene meshes (Dynamesh®) were implanted laparoscopically, using cyanoacrylate glue (Ifabond®) or conventional fixation (Securestrap®). In half of the animals the fascial defect was closed before mesh placement. After 1 day (n = 6), 2 weeks (n = 8) and 6 months (n = 6), a second laparoscopy was performed at which hernia recurrence, mesh integration and adhesion formation were evaluated. After euthanasia, burst strength testing and histopathology were evaluated. RESULTS: One animal died due to intestinal incarceration. In 20 surviving animals, no hernias were diagnosed and mesh placement was satisfying. Adhesions could hardly be observed after 1 day but were omnipresent in both groups at 2 weeks and 6 months. Burst strength testing exceeded 100 N in all samples, independent of the fixation device used. Not after 1 day, but after 2 weeks the inflammatory cell response was significantly higher in the glue group. At 6 months minor inflammation was seen, as was foreign body reaction (FBR). CONCLUSIONS: Using a standardized biomechanical testing system, synthetic glue can be considered an effective fixation tool in LVHR. The possible tissue toxicity of cyanoacrylates does not lead to an increased FBR. No difference in burst strength was observed for closing or not closing the defect.
Subject(s)
Cyanoacrylates/administration & dosage , Hernia, Ventral/surgery , Herniorrhaphy/methods , Surgical Mesh , Tissue Adhesives/administration & dosage , Abdominal Wall/surgery , Animals , Disease Models, Animal , Laparoscopy , Peritoneum/surgery , SheepABSTRACT
A rare case of central pontine myelinolysis and associated extrapontine myelinolysis is presented. The MR findings confirmed the observations reported in recent papers.
Subject(s)
Demyelinating Diseases/diagnosis , Magnetic Resonance Imaging , Pons/pathology , Alcoholism/complications , Demyelinating Diseases/complications , Humans , Male , Middle Aged , Tomography, X-Ray ComputedABSTRACT
A gravity feed extruder was adapted to monitor the extrusion forces, the temperature during processing and the rotational speed of the extruding cylinders. The extruder was used to evaluate the influence of particle size of insoluble material and of product solubility on the extrusion forces. Microcrystalline cellulose, dicalcium phosphate dihydrate and different lactoses were used as model compounds. Difference in lactose and microcrystalline cellulose particle size did not influence extrusion forces. The amount of water in the mixtures to be processed and the initial difference in solubility for some of the lactose types investigated influenced the extrusion forces dramatically. Extrusion forces recorded during processing of a mixture previously granulated in a high shear granulator were higher than when processed in a planetary mixture. Loss of water during high shear granulation is probably the main cause of this phenomenon.
Subject(s)
Technology, Pharmaceutical/instrumentation , Calcium Phosphates/chemistry , Cellulose/chemistry , Equipment Design , Lactose/chemistryABSTRACT
Atherosclerosis as a cause of spontaneous dissection in the cervical internal carotid arteries has been described in only a few cases. The authors present a surgically and pathologically proven case of dissection on the base of atherosclerosis of the cervical internal carotid artery. A resection of the pathologic segment with arterial reconstruction by direct anastomosis with a venous patch graft was performed. The postoperative course was uneventful.
