Pharmacokinetics and tolerability of intravenous infusion of the new hydroxyethyl starch 130/0.4 (6%) in 19 subjects with mild to severe renal impairment: terminal half life and peak concentration (Cmax)remain unaffected

Abstract

P2Model-based neuro-fuzzy control of FiO 2 for intensive care mechanical ventilation HF Kwok, GH Mills, M Mahfouf, DA Linkens Introduction: In our experience, very often, even with a nonrebreathing mask (NRM), high oxygen delivery to patient with the existent materials is insufficient. However, many of these patients need high oxygen therapy for a limited period of time. In this study we report our experience with a new device that serves to increase the concentration of oxygen delivered by a classical nasal cannula or catheter. It is not an oxygen mask. Aim:To demonstrate how a simple adjunctive system to classical nasal cannula or catheter improves considerably the oxygenation of patients at constant O 2 flow rate.Design: Prospective, observational study. Method:The double trunk mask (DTM) is a modified tusk mask described by Hnatiuk. It is composed by a normal aerosol mask with 22 mm of diameter lateral holes, 38 cm of long flexible tubing are inserted to each side of the mask. The DTM is just applied to the face of the patients who already receive O 2 through a nasal cannula or catheter. Forty-five consecutive patients, admitted in the ER or ICU, and needing oxygen delivery, are included in our study. The data collected are: PaO 2 , PaCO 2 , breathing rate with a mean flow rate of 3.58 l/min, at t0, t30 min prior to DTM and then 30 min after DTM application. Results:Nasal The knowledge-based approach to fuzzy logic control of mechanical ventilation on the ICU can be prone to bias in the experts' knowledge and errors resulting from poor communication during rule-base derivation. Therefore, a different approach was explored in the development of a fuzzy controller to control the inspired oxygen fraction (FiO 2 ). The performance of such a controller was compared with the performance of the clinicians.Method: (1) The development of a neuro-fuzzy controller. This was developed by training a neural network to generate an optimal change in the FiO 2 in order to achieve a target arterial oxygen tension (PaO 2 ) on a mathematical model of the gas exchange system (SOPAVent). The neural network learnt the relationship between the blood gases, FiO 2 and PEEP and other ventilator settings. This was done by exposing the neural network to the blood gas results produced by applying a range of FiO 2 and PEEP values to the SOPAVent model. This first neural network was then combined with another neural network which represented a fuzzy logic rule-base. The fuzzy rule-base consists of a set of 'If …, Then …' statements based around combinations of FiO 2 , PEEP and PaO 2 . The fuzzy rule-base was then adjusted by changing the weights of the neuro-controller (which correspond to the 'Then …' part of the fuzzy rules) during neural network training. The neuro-controller output is equivalent to the output from a fuzzy inference system of three inputs (the difference between the actual PaO 2 and the target, the PEEP level and the FiO 2 ).(2) Comparing neuro-fuzzy and clinicians' control. The scenarios were based on the data from th...

Effect of Hydroxyethyl Starch Solution in Normal Horses and Horses with Colic or Acute Colitis

“…Hydroxyethyl starch metabolic products (threshold 40 000 Da) are excreted primarily through the kidneys (Foerster et al, 2001). HES improves kidney perfusion, as well as increases urine volumes and creatinine clearance, which means that a single infusion of HES can be given to geriatric patients with mild to severe renal failure (Jungheinrich et al, 2001). In controls, the specific gravity of urine increased following 5 and 10 ml/kg infusions of HES, although the concentration of urea and creatinine remained the same during the entire observation period.…”

Serum Elimination of HES in Moderately Reduced Renal Function

“…Dass das Ausmaû und die Geschwindigkeit der renalen Elimination von HES bei mäûiggradiger Nierenfunktionseinschränkung kaum vermindert werden, lässt sich aus Untersuchungen mit unterschiedlichen HES-Typen (HES 450/0,7, HES 130/0,4) ableiten [21,48]. Somit ist die in vorliegender Studie festgestellte ¾hnlichkeit der initialen Halbwertszeiten von HES 200/0,5 bei normaler und bei eingeschränkter Nierenfunktion durchaus in gutem Einklang mit der Erwartungshaltung.…”

“…Untersuchungen bei terminaler Niereninsuffizienz sprechen für eine Existenz dieses Mechanismus [34]. Für HES 130/0,4 wurden jedoch bei mäûig eingeschränkter Nierenfunktion renale Wiederfindungsraten erhoben, die nur unwesentlich unter denen bei ungestörter Nierenfunktion lagen [48]. Auf vorliegende Studie projeziert würde das für eine tatsächliche Ausscheidung von HES 200/0,5 aus dem Körper ± und nicht für eine Umverteilung innerhalb des Körpers ± sprechen.…”