There was linear correlation between airway pressures and CI and MAP but not between central and gastrointestinal perfusion. Despite improvement of arterial oxygenation the decrease in CI and, therefore, in oxygen delivery PEEP resulted in a decrease in gastrointestinal oxygenation.

The surgical evaluation of haemorrhagic infarcted intestine and the decision for or against bowel resection require a lot of experience and are subjective. The aim of this prospective, clinical study was to examine the correlation between oxygen saturation and small intestinal wall (IW) thickness, using two objective methods. In 22 colicky horses, the blood flow, oxygen saturation and relative amount of haemoglobin were measured intraoperatively via laser Doppler and white light spectroscopy (O2C, oxygen to see, LEA Medizintechnik) at six measuring points (MPs) in small and large intestines. Furthermore, the IW thickness was measured ultrasonographically. Nine of 22 horses had an increased small IW thickness greater than 4 mm (Freeman 2002, Scharner and others 2002, le Jeune and Whitcomb 2014) at measuring point 1 (MP1) (strangulated segment), four horses had a thickened bowel wall at measuring point 3 (MP3) (poststenotic) and one at measuring point 2 (MP2). The oxygen saturation was 0 at MP1 in six horses, at MP3 in two horses and at MP2 (prestenotic) in one. Oxygen saturation and small IW thickness were independent of each other at MP1 and MP2. At MP3, the two parameters were negatively correlated. In summary, it is not possible to draw conclusions about oxygen saturation based on IW thickness.

NSAIDs are commonly used in colic therapy. Especially in the post-operative stage, dysmotility is a severe complication. Literature provides evidence of an effect on the contractility of the gastrointestinal tract through NSAIDs. Therefore, the aim of this study was to investigate the effects of NSAIDs on the equine small intestine and, in particular, to accurately examine the effects on the injured intestine. Included were horses with a healthy intestine which had been subject to a median laparotomy with two consecutive experimental ischemias and reperfusions. In the first experiment, an in vitro application of the NSAIDs flunixin and firocoxib was carried out. In the second experiment, the respective NSAID was administered to the probands in vivo and the samples were examined by means of a measurement of the contractility in vitro. The in vitro application of the non-selective COX inhibitor flunixin had significant inhibitory effects on the contractility of the equine jejunum in vitro. These inhibitory effects occurred in comparison to all other samples. In vitro application of firocoxib had no significant effects on the contractility in vitro but showed a slight insignificant increasing effect, especially on the frequency of contractions of the circular musculature. After intravenous in vivo application, subsequent sample taking and examination, the results of the measurements of contractility in vitro were clearly more heterogenous. This, for example, led to a significant increase in frequency of contractions of the longitudinal musculature of the samples, damaged by ischemia and reperfusion, after intravenous application of flunixin, and to a significantly higher amplitude of contractions of the longitudinal musculature of the samples, damaged by ischemia and reperfusion, after intravenous application of firocoxib. These inconsistent effects and the deviations to the effects after in vitro application probably indicate a toxicological effect after in vitro application of the agents and an altered initial situation in the second experiment due to a panenteric occurrence (resulting from previous damage through the first experiment). The explanation would be an overdosage and, therefore, an intoxication of the tissue after in vitro application of the agents because the inhibitory effects of flunixin only occurred in high concentrations. Based on the examinations of the current study, significant differences between the in vitro application of flunixin and firocoxib on the in vitro contractility of the equine jejunum could be determined. The inhibitory effects of flunixin were dependent on its concentration and only appeared in high concentrations (2.7×10-5 M). Although the dosages applied in vitro, were oriented towards plasma concentrations of the agents after intravenous application or concentrations used in other studies, it was not clear whether these concentrations corresponded to the actually reached tissue concentrations after intravenous or oral application of the agents. Due to high plasma protein bind...

Zusammenfassung: Schäden des Darmes durch Ischämie und Reperfusion infolge von Strangulationen des Darmes wie sie innerhalb eines Kolikgeschehen vorkommen können, führen zu inflammatorischen Reaktionen der betroffenen Darmsegmente mit einer Hochregulierung der COX-Isoformen. In der Koliktherapie werden NSAIDs, deren Angriffspunkt die Cyclooxygenase ist, zur Analgesie, Entzündungs-hemmung und Behandlung von Endotoxämien eingesetzt. Sie sind die am häufigsten eingesetzten Analgetika in der Tiermedizin und sie haben daher eine große Bedeutung. Die Wirkungen der verschiedenen NSAIDs sind unterschiedlich und aufgrund der Vor-und Nachteile muss bei jedem Patienten individuell evaluiert werden welches das geeignete NSAID zur Therapie sein kann. Hier werden die Grundprinzipien der Funktionsweise der nichtsteroidalen Antiphlogistika beleuchtet und die beim Pferd eingesetzen Medikamente dieser Gruppe aufzeigt. In einer Literaturübersicht wird speziell auf die Auswirkungen auf die gastrointestinale Motilität und Kontraktilität, Regeneration der Darmbarrierefunktion, Ulcera, lokale und systemische Wirkungen der Cyclooxygenase Inhibition, Neutrophilen Infiltration, CycloxygenaseRegulierung und operativer Outcome sowie den paralytischer Ileus eingegangen. Diese Ausführungen werden mit Ergebnissen aus eigenen Studien weiter vertieft. In der Zukunft sollten Studien folgen, die die Effekte selektiver und nicht selektiver NSAIDs nach intravenöser in vivo Applikation weiter untersuchen, um Hilfestellungen in der Wahl eines geeigneten NSAIDs, besonders in der postoperativen Therapie nach Kolikoperationen, bieten zu können.Schlüsselwörter: NSAID, Kolik, Koliktherapie, Analgetika, Schmerz, Schmerzmanagement, COX-Hemmer, Cyclooxygenase, Pferd Non-steroidal anti-inflammatory drugs in colic-therapyInjuries of the intestine caused by ischemia and reperfusion after strangulation leads to inflammatory reactions of the affected intestinal segment by an upregulation of the COX isoforms. The basic principles of the operation mode of NSAIDs are described and the drugs of this group, which are used in horses are presented. A literature-review focusses on the effects of NSAIDs on gastrointestinal motility and contractility, regeneration of the intestinal barrier function, ulcers, local and systemic effects of cyclooxygenase inhibition, neutrophil infiltration, cyclooxygenase regulatory as well as operative outcome and paralytic ileus. These explanations were deepened by results from own studies. In colic therapy, NSAIDs are applied in order to target the cyclooxygenase, being used for analgesia, anti-inflammatory and treatment of endotoxaemia. Motility disturbances of the intestine lead to severe complications and to death of the equine patients particularly in the post-operative stage. Because of different effects and resulting advantages and disadvantages an evaluation for each individual patient is necessary.