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- Klinik für Anästhesiologie und Intensivmedizin (7) (remove)
Despite a plethora of therapeutic approaches, the injection of local anaesthetics itself remains one of the most painful and dreadful procedures among children. Stimulation of acupoint LI4 is associated with analgesic effects in dentistry. Goal of the study To investigate whether stimulation of LI4, added to standard therapy (ST), reduces pain and distress during injection of local anaesthetic (LA) in comparison with ST alone. Materials and Methods Children, scheduled for dental treatment in local anaesthesia on 2 separate days were enrolled in this trial, approved by local ethics commission. On one day each child received bilateral acupuncture of LI4 point, using indwelling fixed “New Pyonex” needles (0.2 x 1.5 mm; Seirin, Japan). The parents of the children were asked to stimulate the needles by massage. Standardized injection of LA was performed 5 min following acupuncture. The needles were withdrawn at the end of dental treatment. On the other day of treatment children received LA injection without acupuncture. The order of treatment days (acupuncture first or vice versa) was randomised. Primary endpoint was the pain intensity during LA injection reported by children on Visual Rating Scale from 0=no pain to 10=maximal pain imaginable (VRS-11). Secondary endpoints were parent- and dentist-assessed pain intensity (measured on Numeric Rating Scale 1-10), patients’ heart rate before and during dental treatment and satisfaction with received therapy (measured on Numerical Rating Scale 1-5.) Side effects of LI4 stimulation were also recorded. Results and Discussion The data of 49 children (22 females; age 10 ± 4 yrs; mean ± SD), who completed both visits, were analysed. Children reported less pain with than without acupuncture: 2.2 ± 2.5 vs. 3.9 ± 2.7; mean ± SD, p<0.001. Heart rate decreased after LI4 stimulation compared to ST alone throughout the dental treatment (p<0.05). LI4 stimulation was safe and raised better satisfaction with the treatment among children and parents, than ST alone (p<0.05). Other secondary endpoints were comparable between both sessions. Conclusion Stimulation of acupuncture point LI4 reduces pain and autonomous stress during injection of local anaesthetics in paediatric dentistry.
Although the benefit of expedient antibiotic therapy remains unquestioned, little is known about the effects that are unrelated to their antimicrobial property but which the antibiotics may exert upon the septic microcirculation. Impairment of intestinal microcirculation has been recognized as an important factor in the pathogenesis of the septic syndrome (intestine = ¡°motor¡± of multiple organ failure). To examine the effects of various antibiotics on microcirculation is justified by the fact that one of major features of sepsis is disturbance of microcirculation. However, monitoring of pharmacological effects on intestinal blood flow is nearly impossible during acute therapy in humans and requires sophisticated equipment when applied to experimental animals. Therefore, the aim of this study was to evaluate the effects of common antibiotics on intestinal microcirculation using intravital microscopy (IVM) and on the release of the cytokines in septic and endotoxemic rats. In a first series of experiments we induced sepsis by using colon ascendens stent peritonitis (CASP) model in the rat (16 hours prior microscopy). We evaluated the effects of common antibiotics on intestinal microcirculation using intravital microscopy (functional capillary density (FCD) and leukocyte-endothelial interactions) and on the release of the cytokines TNF-¥á, IL-1©¬, IL-6 and IL-10. Metronidazole (MET) (10 mg/kg); imipenem (IMI) (20 mg/kg); tobramycin (TOB) (25 mg/kg); vancomycin (VAN) (70 mg/kg); and erythromycin (ERY) (5 mg/kg) were given intravenously 16 hours following sepsis induction. To differentiate antimicrobial from anti-inflammatory effects we performed a second series of experiments using endotoxin (LPS, i. v.) and intravital microscopic examination was performed 2 hours later. Cytokine release was estimated at the end of the experiments. In the CASP model, acute administration of metronidazole was associated with an improvement of markers of the intestinal microcirculation in septic rats (CASP). Our study showed that vancomycin stimulated leukocyte rolling, while erythromycin prevented the activation of leukocyte-endothelial interaction in postcapillary intestinal venules (V1) that occurred within 16 hours after CASP. TNF-¥á release in untreated CASP rats was twice as high in comparison to all antibiotic-treated CASP rats, except in CASP rats treated with tobramycin. Key findings of the present study are that MET and ERY were more potent than other antibiotics in improving the intestinal microcirculation in the CASP model. Protective effects of metronidazole, erythromycin and vancomycin upon the microcirculation were found in LPS model. The administration of MET or VAN or ERY led to significantly higher FCD values within the longitudinal muscular layers. Metronidazole and erythromycin significantly reduced the n umber of sticking leukocytes within the V1-venules of LPS-challenged animals. Leukocyte rolling flux was significant increased within the V1- and V3-venules of the endotoxemic rats treated with VAN. Some antibiotics showed immuno-modulatory effects: MET or IMI or VAN treated LPS rats showed increased IL-10 levels; while ERY treated LPS rats showed decreased IL-1©¬ and increased IL-6 concentrations. In conclusion, metronidazole and erythromycin exerted a positive influence upon the intestinal perfusion not only within septic microcirculation (anti-bacterial effect) but also in a pathogenically independent manner (anti-inflammatory effect); vancomycin had only anti-inflammatory actions in the endotoxin model without bacterial infection. Imipenem and tobramycin had no effect on intestinal microcirculation in septic and endotoxemic rats. The clinical usefulness of studies such as this is that they could provide important information about possible side effects or indicate some potential beneficial effects of the antibiotics. They can influence not only microcirculation but also inflammatory processes by some mechanisms that are probably unrelated to their antibiotic effect. However, these effects may be particularly relevant to the intestinal microcirculation which plays an essential role in the development of multi-organ failure in the instance of sepsis.
With high prevalence and mortality, myocardial infarction constitutes a social and economic burden in Germany and worldwide. Current guidelines for MI treatment require prompt reperfusion to salvage heart tissue and minimize short- and long-term complications. However, there are currently no treatments available to attenuate reperfusion injury. Ischemic as well as pharmacological post-conditioning have been identified as important clinical strategies to improve outcome. Membrane stabilizers, like Poloxamer 188 (P188), have been shown to improve myocardial ischemia reperfusion (IR) injury and mitochondrial function but have not yet been proven to directly offer mitochondrial protection. Mitochondrial function is crucial for cardiomyocyte function, and mitochondrial dysfunction plays an important role in myocardial injury.
In this study, hearts from 79 Sprague Dawley rats were isolated and perfused ex-vivo with oxygenated Krebs Buffer for 20 min before 30 min of no-flow ischemia. Hearts were reperfused for 10 min with Krebs buffer or 1 mM P188. Cardiac mitochondria were isolated with 1 mM P188 vs 1 mM polyethylene glycol (PEG) vs vehicle by differential centrifugation. Mitochondrial function was assessed as adenosine triphosphate (ATP) synthesis, oxygen consumption and calcium retention for complex I and II substrates of the respiratory chain.
An improvement of myocardial function with 10 min P188 post-conditioning could not be shown. Direct mitochondrial protection of P188 or PEG could not be observed in this model either. Further research is needed to ascertain whether P188 has a direct protective effect on mitochondria and, if so, on what pathways of IR injury it acts.
I/R injury occurs during stroke and TBI. It represents a complex pathological event including several processes that can lead to cell membrane disruption, cellular dysfunction and death. The reintroduction of blood flow after the ischemic event may cause detrimental injury to the brain beyond the harm caused by ischemia itself and, therefore, represents a clinical challenge. This so-called I/R injury damages cells in a variety of ways including poration of cell membranes. Hence, methods to improve the endogenous membrane resealing capacity are crucial to prevent neuronal injury.
In the present work, treatment during reoxygenation with the probably most studied CCMS, P188, was investigated in an in-vitro simulation of stroke and TBI in primary isolated cortical mouse neurons. P188 offers a unique hydrophilic/lipophilic character that has been reported to protect different cells and tissues in various experimental settings against I/R and mechanical injury by sealing membranes. The aim of this study was to establish an in-vitro stroke and TBI model and further investigate if P188 directly interacts with neurons after compression and H/R (simulated I/R) injury, when administered at the start of reoxygenation.
The outcome of this treatment was evaluated in regard to cell number/viability, mitochondrial viability, membrane damage by LDH release and FM1-43 incorporation as well as activation of apoptosis by Caspase 3. It could be demonstrated that 5 hours hypoxia ± compression with 2 hours reoxygenation appear to be a suitable model for testing novel treatments. Compared to normoxic cells not exposed to compression, cell number and mitochondrial viability decreased, whereas membrane injury by LDH per total/FM1-43 dye incorporation and Caspase 3 activity increased in cells exposed to hypoxic conditions ± compression followed by reoxygenation.
However, it could not be shown that P188 is capable to protect isolated neurons from H/R and/or compression injury when administered purely as a postconditioning agent. It therefore seems likely that P188 does not directly affect isolated neurons. Yet, it may be able to provide neuronal protection in a different experimental setting.
In conclusion, this work contributes a new model of simulated stroke and TBI in-vitro. In addition, further knowledge about the impact of P188 on injured neurons can be gained. The extent to which the in-vitro results can be transferred to in-vivo mechanisms is yet unclear and offers opportunities for further investigations.
We improved our previous model of tracheal tube preparation and examined the effects of oral treatment of rats with carbocisteine (CCS) and its interaction with bronchial epithelium. The model permitted isometric or isotonic measurements of smooth muscle contraction or relaxation in cannulated or tracheal ring preparations, with or without epithelium. We found that oral treatment with carbocisteine and not preincubation of preparations in vitro, diminished sensitivity of preparations without epithelium to carbachol (EC50, -log(M) values: IN -luminary perfusion, -EP, controls vs. CCS: 5.8±0.06 vs. 5.5±0.09, p<0.005; OUT - serosal perfusion, -EP, controls vs. CCS: 5.9±0.06 vs. 5.6±0.05, p<0.005), while the sensitivity to aminophylline, degree of shortening, and the velocity of contraction of rat tracheal rings stimulated by 10-6M carbachol was not affected. Normal sensitivity to carbachol stimulation was re-established if preparations were preincubated with capsaicin. We conclude that carbocisteine has small inhibitory effects on the sensitivity to carbachol of the rat tracheal smooth muscle denuded of epithelium. Described model is valuable for examining the effects of bronchial epithelium on bronchial smooth muscle contraction.
To this day, the patient’s outcome after any form of cerebral ischemia is often mediocre
at best. The added damage that occurs at reperfusion after ischemia seems to be as
important as the ischemic injury itself. New therapeutic strategies targeted at this
critical issue are therefore crucial. P188, an amphiphilic triblock copolymer, has risen
to be one of the most promising pharmacological therapeutics, as its capability to insert
into injured cell membranes seems to perfectly fit the needed criteria to protect against
I/R injury. Lately, it has become apparent that mitochondrial function particularly profits
from P188 treatment after I/R injury. Therefore, the question arose, if P188 may
interact directly with mitochondria.
In the present study, rat isolated brain mitochondria were injured and then treated with
P188. The injury took place either in vivo by asphyxial cardiac arrest before isolation
of mitochondria or in vitro after isolation by addition of the ROS H2O2. After treatment
with P188, mitochondrial function was evaluated through the assessment of ATP
synthesis, O2 consumption and CRC.
10 or 15 min of asphyxia in vivo as well as 200 μM H2O2 for 10 min in vitro significantly
impaired mitochondrial function. Furthermore, a damaging effect of RT on isolated
mitochondria became apparent. Contrary to the underlying hypothesis, P188 did not
preserve mitochondrial function independently of the injury mechanism chosen.
In conclusion, in the context of studying P188, two new methods of I/R injury
simulation, namely asphyxial cardiac arrest in vivo and the injury with H2O2 in isolated
mitochondria in vitro, have been established. However, it is not yet conclusive, if P188
does or does not directly improve mitochondrial function after I/R injury. Further
research looking at different injuring methods as well as modulating the treatment
method is needed to ultimately clarify this question.
Telemedicine at the Emergency Site – Evaluated by emergency team members in simulated scenarios
(2015)
The hypothesis of this study states that emergency medicine can benefit from telemedicine, whenever paramedics at a remote emergency site request consultation or mentoring by a distant emergency doctor. The hypothesis was semi-qualitatively evaluated in accordance with the protocol of the EU project in the setting of a medical simulation centre. Paramedics encountered simulated standardized emergency case scenarios, connected for teleconsultation and telementoring with emergency doctors by video and audio link through a newly developed real-time HD-video system called LiveCity camera. Paramedics and emergency doctors regarded the simulated scenarios as realistic and relevant and took the simulation seriously. Thus,the following conclusions can be drawn: 1.) Emergency team members encounter situations at the emergency site, in which they would like to get help by a more experienced colleague, especially help with diagnostics and treatment. 2.) The telemedical contact to an emergency doctor makes paramedics feel confirmed in their work, more secure, even in legal aspects. Paramedics do not feel controlled by telemedicine or like a puppet on a string. Their relationship to the patient is not mainly deranged or interfered by the doctor and their course of action is not mainly disrupted. The tele-emergency doctors do not feel like puppet masters and continue feeling as doctors and do not perceive themselves as interferer within the emergency team. 3.) Emergency team members call for a telemedical system providing transmission of vital signs as well as audio- and video-connection. 4.) The LiveCity camera is an effective telemedical tool. The audio quality is good and the orientation on the screen is easy. Paramedics state, that filming the emergency site is easy, does not restrict the field of vision and paramedics can communicate the emergency doctors everything they want to show and tell. Thus the emergency doctors get additional information. While the LiveCity camera is mostly perceived as not too heavy, the LiveCity camera is not easy to operate, very failure-prone and can derange the communication among team members at the emergency site. Nevertheless, the LiveCity camera is not perceived as an additional burden. 5.) Telemedicine is predominantly and largely appreciated by the members of the emergency team. Connecting the tele-emergency doctor to the remote paramedics leads to a perceived faster start of the therapy and is considered as helpful, improving the situation and the quality of patient care. The adherence to medical guidelines and therefore the quality increased, when the paramedics were connected to an emergency doctor through the telemedicine connection. In general, the quality of diagnostics, the correctness of diagnosis and the quality of therapy were rated higher. The majority of paramedics would call a tele-emergency doctor in cases, they wouldn´t normally activate medical support. The emergency team members largely agree in perceiving the tele-emergency doctor system as useful, and they can imagine, working in a tele-emergency system. As a conclusion, the general hypothesis of this study is mainly and in many items supported: Emergency medicine benefits from telemedical support via video- and audio link as studied here with a newly developed real-time HD-video system called LiveCity camera, whenever paramedics at a remote emergency site request consultation or mentoring by a distant emergency doctor.