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Objective: In Germany, injection and inhalation anesthesia with the addition of an analgesic drug are an interim solution to surgical castration under general anesthesia due to the ban on non-anesthetic castration of male suckling piglets under 8 days of age. However, the efficiency of both anesthetic procedures is submit to controversial discussion. Most of the studies addressing this question only examined one of the procedures in comparison to piglets castrated without anesthesia or uncastrated controls. Comparisons between the anesthesia methods, especially under conditions of organically working farms, are almost completely lacking. The aim of the present study was therefore to compare the efficacy of injection and inhalation anesthesia under practical conditions in 7 organic farms as well as to examine the effect of metamizole administered in addition to meloxicam., Material and Methods: For this purpose, 514 male suckling piglets were examined with regard to anesthesia efficiency (reflex test, defence behaviour), body temperature, post-operative bleeding and wound healing, post-operative behavior and pain behavior as well as the course of the recovery phase., Results: The results show a basic superiority of inhalation anesthesia over injection anesthesia, especially in the areas of anesthetic efficacy, thermoregulation and duration of the recovery phase. In 7.7 to 15 % of piglets, the perianal and interclaw reflexes studied were still present at the time of castration. Following injection and inhalation anesthesia, in total 83.6 (25.2 %) of the piglets showed at least one of the following criteria: positive reflex response, clear defensive movements or vocalisations. Body temperature dropped by 0.41 °C under inhalation anesthesia and by 1.82 °C under injection anesthesia. Post-castration bleeding and wound healing were hardly influenced by the type of anesthesia. Almost all piglets showed signs of pain and pain-associated behavior for 5 and 72 hours after castration, regardless of the type of anesthesia. The post-castration recovery phases lasted significantly longer after injection anesthesia (107 minutes) than following inhalation anesthesia (33.3 minutes) until the piglets were returned to the sow., Conclusion: Neither injection nor inhalation anesthesia in spite of additional administration of meloxicam, nor the supplementary use of metamizole, fulfil the EU requirements for painless castration., Clinical Relevance: The necessary analgesia during and after castration of male suckling piglets is not achieved under either isoflurane or ketamine/azaperone anesthesia, despite the use of meloxicam and metamizole., Competing Interests: Die Autoren erklären es gibt keinen Interessenskonflikt., (Thieme. All rights reserved.)

Competing Interests: Disclosure The authors report no conflicts of interest in this work.

Objectives: Survey concerning the situation of small animal anesthesia in Europe and assessment of the compliance with the guidelines of the AVA (American Society of Anesthesiologists) and the DVG specialty group VAINS (Veterinary Anesthesia, Intensive Care, Emergency Medicine, and Pain Management)., Material and Methods: A link to an online survey with questions concerning anesthesia management (topics include demographics, equipment, monitoring, thermal management, pre-anesthetic examination, anesthetic protocol, and others) was sent to small animal practitioners in several countries., Results: A total of 767 evaluable questionnaires came from Germany (n = 343), Austria (n = 216), Switzerland (n = 83), the United Kingdom (n = 38), France (n = 25), Hungary (n = 25), Scandinavia (n = 23), and "other countries" (n = 11). On average, 91 % of respondents complied with the AVA guideline and 58 % complied with the VAINS specialty group guideline even before its publication. Practices/clinics with higher staff possessed superior equipment, and practices/clinics performing higher numbers of anesthesias per week were more likely to implement "good preliminary examination.", Conclusion and Clinical Relevance: Although the guidelines were found to be implemented to a certain degree, the presented study reveals a potential for optimization of the anesthesia regime in many practices/clinics, e. g. by improving the equipment or allowing for better use of present apparatus., Competing Interests: Die Autoren bestätigen, dass kein Interessenkonflikt besteht., (Thieme. All rights reserved.)

Objective: Cardiac diseases, predominantly acquired diseases such as valvular insufficiency and cardiomyopathies, are a common problem in domestic ferrets. Aim of the present study was to establish body-weight related echocardiographic reference intervals for standard B- and M-mode parameters, especially of the left atrium, in clinically healthy ferrets without sedation., Material and Methods: Eighteen client-owned healthy, non-sedated ferrets underwent echocardiography in right lateral recumbency. Mean values were calculated from the evaluation of 3 cardiac cycles with good wall differentiation within 3 M-mode measurements in the right parasternal long axis view (level of the chordae tendinae, tip of the mitral valve and level of the aortic root and left atrium). Additionally, measurements of the left atrium (LA) and aorta (Ao) were performed in the short axis view at the level of the aorta and the LA/Ao ratio was calculated., Results: The 9 neutered male and 9 neutered female ferrets had a mean age of 2.6 ± 1.3 years and a mean body weight of 1.04 ± 0.31 kg. M-mode measurements of the left ventricle and the aortic root were possible in all animals. Body weight exerted a significant effect on the ventricular dimensions in diastole and systole as well as on the measurements of the left atrium and the aorta. In the B-mode evaluations, measurements of the aorta and the left atrium were frequently only performable on a static image. A significant effect of body weight on the dimensions of both aorta and left atrium were also apparent in the B-mode measurements. Calculated values such as fractional shorting and LA/Ao-ratio proved to be independent of body weight., Conclusion and Clinical Relevance: Standard B- and M- parameters may be used in routine examinations in order to evaluate cardiac morphology in the non-sedated ferret. Consideration of the body weight is warranted in this species., Competing Interests: Die Autoren bestätigen, dass kein Interessenkonflikt besteht., (Thieme. All rights reserved.)

Competing Interests: Disclosure The authors report no conflicts of interest in this work.

Objective: Evaluation the development of perioperative body temperature while administrating a combination of acepromazine and metamizol (AM) versus anesthesia with acepromazine (A) alone., Material and Methods: In this prospective, quasi-randomized controlled study 20 dogs undergoing standardized tibial plateau leveling osteotomy were alternatingly assigned to group A or group AM (n = 10 each). The patients' body temperature values were recorded from the time of premedication up to its post-surgical return to reference values., Results: Body temperature decreases during anesthesia in both groups were comparable (p = 0.12). Postoperatively on the other hand, temperature development differed significantly between the two groups (p = 0.0455). In 6 dogs of the group AM, body temperature continued to decrease following extubation prior to returning to normothermic values., Conclusion: Intraoperatively, all patients developed hypothermia, regardless of the investigated anesthetic medication administered. Postoperatively, patients not receiving metamizol reached normothermia more rapidly., Competing Interests: Die Autoren bestätigen, dass kein Interessenkonflikt besteht., (© Georg Thieme Verlag KG Stuttgart · New York.)

Objective: The aim of this study was to evaluate the consequences of different oxygen supplementation methods on arterial blood gas analysis during an injectable anesthesia., Material and Methods: A total of 29 rabbits with dental diseases (tooth elongation) were sampled before, during and after coronal reduction. Oxygen was provided either via the flow-by method or with a nasal oxygen tube; the control group breathed room air., Results: All patients receiving oxygen developed respiratory acidosis that intensified during the course of anesthesia. Furthermore, these groups experienced reduced respiratory rates intraoperatively, nevertheless they showed elevated oxygen parameters (hyperoxemia) in the arterial blood gas analysis. No significant differences could be demonstrated between the 2 oxygen providing methods. In the control group, pH remained stable, the oxygen parameters however decreased to less than 80 mmHg (hypoxemia)., Conclusions: Although there were no clinical consequences of hypoxemia or hyperoxemia, moderate oxygen support during an injectable anesthesia is recommended due to the development of hypoxemia. A balance between oxygen supply and oversupply needs to be established to aid in avoiding oxygen toxicity., Competing Interests: Die Autoren bestätigen, dass kein Interessenkonflikt besteht., (© Georg Thieme Verlag KG Stuttgart · New York.)

The aim of this study was to describe the practical implementation of the painless castration under injection anaesthesia in Switzerland. 30 swine farms were visited and 60 farmers answered a questionnaire. 34 % of the piglets showed movements during castration under injection anaesthesia and 17 % had excitations during recovery from anaesthesia. After 48 minutes half of the piglets were in sternal position and after 112 minutes half of them showed coordinated movements. The body temperature decreased by 3.1 °C until 60 minutes after castration, especially small piglets reached critical temperature levels. 38 % of the piglets showed strong bleeding after castration. The healing of the wound was good according to 82 % of the farmers. 83 % of the farmers reported piglet losses, especially at the beginning of the anaesthesia period. The anaesthesia may be improved by using butorphanol in addition to the combination of ketamine and azaperone. The recovery of the piglets should be in a warm place without any risk of injury by obstacles or the sow. Increased bleeding can be controlled by using an emasculator.

Objective: In most ocular procedures, a central position of the eye is necessary. This can be achieved using a deep plane of anaesthesia, locoregional blocks or with neuromuscular blocking agents. The aim of this study was to evaluate the influence of atracurium on cardiovascular parameters, and on recovery quality and duration in horses., Material and Methods: Thirty-four warmblood horses undergoing in total 50 vitrectomies were divided into two groups. Premedication, induction and maintenance were identical in all patients. After 20 minutes, horses of group A received atracurium (0.1 mg/kg) while in the control group (group K) the depth of anaesthesia was adapted to keep the bulbus in a central position. Dobutamine and fluids were administered to maintain the mean arterial blood pressure (MAP) above 70 mmHg. Cardiac output (CO), heart rate (HR), MAP, respiratory rate, end-expiratory isoflurane concentration (ETIso) and dobutamine requirements were determined. Position and movement of the globe during the surgical procedure were scored. Time and quality of the recovery period was scored., Results: Horses of group K required significantly higher concentrations of isoflurane (group A: 1.08 ± 0.1%; group K: 1.34 ± 0.2%) and had an overall lower MAP (group A: 88.4 ± 10.3 mmHg; group K: 76.6 ± 11.6 mmHg) and CO (group A: 36.9 ± 11.7 l/min; group K: 28.5 ± 7.2 l/min) but needed significantly more dobutamine (group A: 0.37 ± 0.17 μg/kg/min; group K: 0.99 ± 0.46 μg/kg/min) compared to group A. Complete relaxation occurred 9.5 ± 2.5 minutes after atracurium bolus and lasted for 25 ± 7.1 minutes. The score of the bulbus position and movement was significantly lower in group A, resulting in a better quality for the surgical procedure. In group A, the recovery time to standing was significantly shorter (group A: 18.1 ± 5.4 min; group K: 31.5 ± 7.1 min), with no difference in quality., Conclusion and Clinical Relevance: The use of atracurium resulted in a better cardiovascular condition, probably because of the isoflurane-sparing effect. The recovery time was shorter in these horses without negative effects on recovery quality. No signs of residual atracurium effects were detected.

The objective of this study was to compare the effects of three anaesthetic protocols with respect to possible pain-associated reactions: injection (INJE) with xylazine (0.2 mg/kg), ketamine (5 mg/kg) and local anaesthesia (procain 2%); a combination of injection and inhalation (KOMB) with xylazine (0.2 mg/kg), ketamine (2 mg/kg), and isoflurane (1.5-3.0 vol%); and inhalation with isoflurane (control group [o]) surgery. During the trial, the anaesthetic level was controlled, and signs of response to surgical stimulation or spontaneous movements, changes in heart rate, mean arterial pressure, plasma L-lactate and cortisol levels were recorded. The dosage of 5 mg ketamine/kg body mass was rarely sufficient to obtain surgical tolerance in group INJE. In order to attain surgical tolerance, it was necessary to administer an average of 8.4 mg ketamine/kg body mass. All animals of the INJEc/o groups started to show signs of spontaneous movements or response to surgical stimulation between five and twelve minutes after the last administration of ketamine. Signs of response to surgical stimulation at the time of skin incision were significantly most frequent (37%) in the INHAc group, while agitation or response to surgical stimulation at least once during the entire time of anaesthesia was significantly (p <0.01) most frequent in the INJEc group (100%). Changes in heart rate and mean blood pressure were not found to be related to surgical stress situations.Ten minutes after the incision, the highest increases in plasma cortisol levels above basal levels of the previous day were determined in the groups INJEc and INJEo (53.5 and 57.7 nmol/l, respectively). However, a significant increase of plasma cortisol levels between the previous day and ten minutes after incision was only found between INHAc and INHAo (30.1 versus 7.5 nmol/l, p < 0.01) but not in the other pairs of groups (INJEc/o and KOMBdc/o). Within the three experimental groups the increase of plasma cortisol levels between the previous day and ten minutes after incision was only significant between INJEc and KOMBc (53.5 versus 28.3 nmol/l, p < 0.01). Among the protocols tested in this study, the combination anaesthesia (KOMB) was associated with the least amount of pain-associated reactions by the calves. Therefore, this protocol should be used preferred to the other two protocols in order to minimise stress and pain for the animals as much as posssible.

Unlabelled: Objective of this clinical study was to assess the anaesthetic quality (induction and recovery) and utility of short term alfaxalone anaesthesia in healthy and diseased cats. Cardiopulmonary effects and the influence on haematological and biochemical blood parameters were evaluated., Material and Methods: Twenty feline patients (ASA1-4) were anaesthetized with alfaxalone for various short surgical or diagnostic procedures. Heart rate, breathing rate, end-tidal CO2 partial pressure, arterial oxygen saturation, mean arterial blood pressure and the body temperature were measured and recorded every 10 minutes. Before, after and 6 hours after anaesthesia venous blood samples were taken and haematologic and blood chemistry parameters were determined. Recovery time and quality were assessed by a numerical rating scale., Results: Anaesthetic induction was rapid and smooth in all cats. Spontaneous respiration was maintained in all cats. Cardiopulmonary parameters mostly remained within a clinically tolerable range. Noticeable was a high heart rate (mean >190 bpm) at the beginning of anaesthesia lasting up to 10 minutes. Statistically significant changes (p<0.05) occurred in some haematologic parameters (RBC, haemoglobin, haematocrit and MCV decreased), electrolytes and venous acid-base-status (bicarbonate, chloride and base excess increased, sodium and potassium decreased) and blood chemistry parameters (alanine aminotransferase, glutamate dehydrogenase and creatinine decreased). None of these changes appeared to have clinical relevance. Recovery was smooth in the majority of cats. Mild signs of hyperexcitability (muscle tremor, short term opisthotonus and hyperacusis) occurred in individual animals. The duration of recovery varied between 21 and 93 minutes., Conclusion and Clinical Relevance: Alfaxalone by repeated intravenous injection is suitable for short-term diagnostic and surgical procedures in cats. Because of its minor cardiovascular effects and slight respiratory depression, it is also well tolerated by patients with increased anaesthetic risk (ASA 3 and 4).

The effect of different CO2-stunning on the corneal reflex response and blood parameters in (arterio-venous) killing blood was investigated in n = 614 slaughter pigs (carcass weight = 92-94 kg) at two different abattoirs. CO2-anaesthesia lead to remarkable decrease of PO2 (hypoxaemia), increase of PCO2 (hypercapnia), decrease of pH (respiratory acidosis) and increase of [strong ion difference = SID3] (basic reaction caused by electrolytes). Pigs with subclinical post mortem obtained lung lesions showed no significant modified value of the reflex answer or changes in parameters of killing blood compared to the animals with healthy lungs. The CO2-stunning with 90% CO2 and 120 s exposure time resulted in notably less undesired positive reflex responses (6% of slaughter pigs) than the CO2-stunning with 90% CO2 and only 90 s exposure time (15% of slaughter pigs). The occurence of the positive reflex response, which means an inadequate depth of anaesthesia, in slaughter pigs can be safely eliminated by use of qualified cut off values of killing blood parameters. These parameters can be measured rapidly and validly with ion-sensitive electrodes, making a beneficial monitoring of the used CO2-stunning possible.

33 ferrets (Mustela putorius furo, 11 females, 22 males, ASA I-II) were neutered in a combination anaesthesia with medetomidine, midazolam and ketamine. The animals were randomized into 3 groups. All animals received 20 microg/kg BW medetomidine and 0.5 mg/kg BW midazolam. The three groups differed regarding dosis and way of application of ketamine (IM10 = 10 mg/kg BW intramuscularly; IM07 = 7 mg/kg BW intramuscularly; SC10 = 10 mg/kg BW subcutaneously). After 30 minutes anaesthesia was partially antagonised with 100 microg/kg BW atipamezole i.m.. Sedation, muscle relaxation, analgesia, and overall anaesthetic impression were compared by a scoring protocol. Reactions to painful stimuli of clamping the spermatic cord or the ovarial ligament including the A. ovarica were judged, too. All animals lost their righting reflex and could be placed in dorsal recumbency. Induction and recovery time were significantly the shortest in study group IM10 with 1.73 +/- 0.3 and 9.73 +/- 4.6 min respectively. Recovery was significantly prolonged in group SC10 with 30.27 +/- 15.6 min. The MMK-anaesthesia with 10 mg/kg ketamine i.m. is very useful for neutering ferrets. Respiratory depression and bradycardia typically for medetomidine were seen in all three combinations, but quickly reversed after partial antagonisation. Induction and intubation, followed by inhalation anaesthesia, were possible with all three regimes.

Since the amendment of the animal welfare law in Germany in April 2006, castration of piglets without anesthesia is only allowed in the first seven days of life. However, neonates are capable of feeling pain and react more sensitive to pain than adults. Accordingly we expect that castration without anesthesia will be unaccepted in Germany in the future as castration without anesthesia will be forbidden in Switzerland from 2009 on. Denmark and The Netherlands strive for an embargo of the castration without anesthesia and Norway is already asking for an elimination of pain during castration. In Switzerland castration under isoflurane-anesthesia is considered to be a good alternative for the castration without anesthesia. Whether isoflurane-anesthesia is able to reduce stress caused by castration adequately or anesthesia, especially anesthetization that often provokes defensive reaction, is stress for the animal itself was tested in the following investigation. To get an objective statement about the stress of the animals, concentrations of epinephrine and norepinephrine were detected before and immediately after castration/fixation with or without anesthesia. Five day old, healthy animals were divided into four groups. Animals of group A (n = 10) were only fixed without anesthesia, animals of group B (n = 10) were fixed and castrated without anesthesia. In group C (n = 10) the animals were only fixed under anesthesia and the animals of group D (n = 11) were fixed and castrated under anesthesia. Norepinephrine-concentrations and epinephrine-concentrations did rise significantly in all piglets handled without anesthesia (group A and B) independently if castrated or only handled. The values of these animals were significantly higher than the values of the anesthetized animals after fixation/castration (group C and D). In contrast the norepinephrine-concentrations and the epinephrine-concentrations of all anesthetized animals (group C and D) were significantly lower after castration than the concentrations before castration. The catecholamine peak did not differ significantly between the groups of anesthetized animals. The significant increase of the catecholamines of the non-anesthetized animals can be explained by the stress caused by fixation and/or castration without anesthesia. Because of the anesthesia the catecholamine-concentration was reduced considerably during the fixation and/or castration. The results show that fixation and/or castration under anesthesia causes no stress for the piglets.

According to the applicable animal welfare legislation, the surgical castration of pigs is allowed up until the age of 4 weeks, without anaesthesia. According to the european guideline (2001/93/EG) it is only permitted in the first week after birth. The investigation should show, whether the castration of young piglets takes a milder course and to what extent stress reactions occur in different age groups. The healing process of castration wounds in piglets that were castrated at the age of four days progressed more rapidly and with less complications than those piglets that were castrated at 28 days of age. The catecholamine levels in younger piglets rose significantly after the operation, while these levels virtually stayed the same in piglets castrated at 28 days. As alternatives to castration without anaesthesia, several methods are in discussion: (1) Castration under general anaesthesia can only be practiced by a veterinary surgeon. The sole use of Azaperon and Ketamine has insufficient pain sedating effect. Isofluran anaesthesia is apparatively extravagant. (2) CO2-Anaesthesia in piglets leads to high strain. (3) Castration under local anaesthesia must be practiced by a veterinary surgeon. The application and the pain after the castration are not taken into consideration. (4) Jung boar fattening up until the slaughtering weight of 80 kg is not transformable, because of boar taste. (5) The breeding of slaughter pigs with little boar taint is not yet transformable. (6) Sperm sexing is not and will not, in the near future, be mature for practice. (7) Immunocastration is an active immunisation against GnRH. The immunological elimination of GnRH suppresses the development of sex hormones, such as testosterone, as well as the substance responsible for boar taint, Androstenone. To consider is the acceptance of the consumer. The preparation has the same effect in humans as it has in swine. "Self injections" have the same effect in humans as it has in swine. "Self injections" are therefore risky.

In Germany, Bio-beaker and infra-red irradiation (PSP) are used for beak trimming in turkey chicks as routine methods to prevent feather pecking and cannibalism. By both procedures the animals suffer from extensive damage and considerable continuous pain. Beak trimming is allowed by animal welfare legislation, but the operation requires an official permission and must be carried out under anesthesia. The official intention, due to animal welfare reasons, to decrease this operation and to question it permanently fails because beak trimming without anesthesia is tolerated. Elaboration of alternative programs has been demanded for a long time. Therefore selection of stocks tending less to cause feather pecking and cannibalism as well as adequate keeping and housing conditions during hatching and rearing are proposed.

Pet birds are frequently viewed as difficult patients for anaesthesia. The present paper revises the current anaesthetic procedures for injectable and inhalant anaesthetics. Currently the method of choice for the anaesthesia of pet birds is the isoflurane inhalation anaesthesia. Special emphasis is given to the preanaesthetic preparations. Fasting is shorter for pet birds than for mammals. Anaesthetized birds are at special risk for hypothermia. Methods for the prevention of heat loss are given. The use of analgesics are recommended both for welfare reasons but also because of the possibility to reduce the concentration of inhalation anaesthetics and therefore the amount of possible exposure of personnel to waste gases.

In today's society small rodents and rabbits are increasingly kept as pets. Anaesthesia is necessary for numerous reasons and proves to be a challenge for many veterinarians. Following surgical intervention analgesia is frequently neglected. This article reviews the preparation of small mammals for anaesthesia, the choice of anaesthetics and the possibilities of perioperative care including monitoring, complications, fluid therapy and analgesia.

Ferrets (Mustela putorius furo) show up with increasing frequency in veterinary practice. Originally domesticated for hunting of rodents and rabbits, they became very popular pets which require legal permission though and the further fulfillment of various husbandry needs. Ferrets have to be maintained on a high protein diet which in practice is often done with commercial feline products. Physical examination is similar to dogs and cats whereas the frequent occurrence of non-specific symptoms require further diagnostic investigation including blood sampling, radiology, ultrasound or exploratory laparatomy. The preferred anaesthetic method is the direct face mask induction and maintenance using isoflurane without prämedication. Special attention of veterinarians has to be paid to canine distemper vaccination, the specialized reproduction physiology of the females (jills) which can develop, if unmated, a persistent oestrus with fatal consequences of hyperestrogenism, as well as the frequent occurrence of further endocrine disorders, congestive cardiomyopathy and gastrointestinal diseases.

Since September 1, 2001, castration of male calves and small ruminants in Switzerland is not allowed without anesthesia. The use of rubber rings for that purpose is forbidden. This change of the legislation has been claimed by the Swiss consumers and is aimed to increase the animal welfare. The current paper provides a review of the different techniques of anesthesia and castration that may be advocated in male ruminants. Sedation with xylazine and injection of lidocaine in the area of the base of the scrotum, followed by closed castration with the Burdizzo represents a safe technique for painfree castration of calves and lambs.

The combination of Medetomidine and Butorphanol leads to a sufficient sedation with good analgesia and is thus superior to the application of Medetomidine only. By reducing the dosage of Medetomidine, reduced cardio-respiratory side-effects are to be expected. The comparative application of the two Butorphanol preparations Torbugesic (group T) and Morphasol (group M) did not show any differences concerning effect and tolerance. No statistically significant and clinically relevant differences between the two groups were observed for any of the parameters.

Increasing is the number of Llamas (Llama glama) referred to veterinarians for diagnostic or therapeutic procedures which frequently require sedation or anaesthesia. Much of the knowledge concerning sedation and anaesthesia of domesticated ruminants and horses can be applied to sedate or anaesthetise a llama. A variety of considerations remain special for the llama. The article reviews all aspects of today's knowledge about sedation and anaesthesia of llamas.

All anaesthetic drugs and techniques inhere risks, that can cause illness and death even in the sound. Beside this common anaesthetic risk caused by anaesthesia itself, risks specific for the patient and the surgery, the influence of the anaesthetist and the available facilities are additional factors contributing to the risk involved for any particular animal. In this article the factors in anaesthetic risk and their importance for the individual risk of a patient are discussed. Distinct is that a systemic disease and the resulting incapacity stand for a much higher risk than anaesthesia by itself or the surgery. Beside the preoperative physical status the urgency of the operation has a decisive influence upon the anaesthetic risk. Deficient monitoring and an unrecognized and/or untreated respiratory depression are the most common reasons for anaesthetic death in veterinary medicine. The anaesthetist has a profound bearing on the degree of risk to which a patient is exposed, because most of the avoidable anaesthetic mishaps are caused by human mistakes. The individual anaesthetic risk of a patient is determined with the help of the preanaesthetic examination. Referring to the factors in anaesthetic risk strategies for the prevention of anaesthetic mishaps and complications are discussed.

Renal scintigraphy is one of the diagnostic devices in the upper urinary tract. In 24 dogs of different age, sex and breed that--according to the usual laboratory tests--were considered healthy with respect to renal function, a renal scintigraphy with the tubular excreted tracer 99mTc-MAG3 was performed. The dogs were grouped according to three different anaesthetic regimens in order to estimate the influence of anaesthesia--which is necessary for this investigation--onto function of the normal kidney. Eight dogs were scintigraphed twice using different anaesthesia protocols. In group A (n = 22), anaesthesia was performed with a combination of atropine/diazepam/ketamine/xylazine. The reference range determined was for the period of maximal activity accumulation (Tmax) 3.2 +/- 0.8 min and for the elimination half-time (Tmax/2) 6.3 +/- 1.4 min. MAG3-clearance was 7.5 +/- 1.8 ml/min/kg. Group B (n = 5) received thiopental as a continuous intravenous infusion. Tmax was measured with 2.9 +/- 1.1 min, Tmax/2 with 4.7 +/- 1.2 min and the MAG3-clearance was 6.8 +/- 1.6 ml/min/kg. In group C (n = 5), the dogs were given propofol and halothane, and the values determined for Tmax and Tmax/2 were 4.8 +/- 2.7 and 4.8 +/- 1.4 min, respectively. The MAG3-clearance was 10.0 +/- 2.3 ml/min/kg. It is concluded that the anaesthetic regime used has a distinct influence on the reference values.

In anaesthesiology rabbits and rodents are considered being high risk patients as about 30% of the anaesthetized patients die intra- or postoperatively. Due to the anatomic structures many anaesthetic techniques and patient monitoring are very difficult of even impossible to perform in these animals. For this reason anaesthesia of rabbits and rodents confronts the veterinarian with great problems. The main complications during anaesthesia are discussed and principles of the perioperative anaesthetic management, of anaesthetic techniques as well as patient monitoring are presented.

In the first 12 weeks of postnatal life puppies and kittens are defined by the term pediatric, because of their immature organ systems. In anaesthesiology they are considered as high risk patients. Dogs and cats can be defined by the term geriatric when they have completed 80% of their expected life spans. These patients show age-related decline in organ functions or in their mechanisms of compensation. Physiological and pathophysiological characteristics of pediatric and geriatric patients are discussed and principles of the perioperative anaesthetic management and of pediatric and geriatric anaesthetic techniques are given.

Since the beginning of 1997 the use of the hypnotic drug metomidate (Hypnodil) in swine is not longer allowed. This ban caused a substantial therapeutic deficit for anesthesia in swine. The ban is based on provisions of the European Council Directive 2377/90 for fixing maximum residue limits (MRL) of veterinary drugs in animal-derived food and due to the fact that the pharmaceutical industry has not submitted any application for determining an MRL for metomidate. According to the regulations of the German drug law only those substances can be used as alternatives which are authorized for use in swine or another food-producing animal species. Registrations for use in swine exist for the barbiturates thiamylal and narcobarbital, for ketamine and for the neuroleptics azaperone, acepromazine and propionylpromazine. In the exceptional case of therapeutic emergency levomethadone or xylazine can be used. The administration of propofol, thiopentone, opioids (except levomethadone) or benzodiazepines (except brotizolam) to swine is not allowed since these drugs are authorized only for use in humans or companion animals. At present the most appropriate alternative for anesthesia in swine is thiamylal after premedication of azaperone and ketamine inducing general anesthesia with sufficient tolerance at low risks. In current studies general anesthesia with tolerance could further be produced by combinations of levomethadone, ketamine and azaperone or xylazine. Combined use of levomethadone with benzodiazepines appeared to be not suitable in swine.

The presentation of small animals and exotic pets (birds, reptiles) in veterinary practice is increasing. Physiological and ethological variations demand specific precautions in restraining/ anesthetizing these patients. In Psittacines hypoglycemia, hypoxia and hypothermia are typical side-effects. Long-acting recovery control in birds and reptiles is necessary.

Because of bradyarrhythmic complications under anesthesia in two Airedale Terriers, we performed a prospective search of ECG-abnormalities in healthy dogs of that breed. Resting ECG's were screened for routine abnormalities. None of the 42 dogs investigated so far had a completely normal ECG. Among the common abnormalities were: deviation of the mean electrical axis (MEA) in 32 dogs, low voltage QRS-complexes in 22 dogs, and AV-blocks 1st degree in 14 dogs. None of the recorded abnormalities with the exception of AV-blocks, were considered predictors of anesthetic complications. Because of the high frequency of recorded abnormalities, we are continuing this prospective study.

The continuous fiberoptical measurement of the mixed venous partial oxygen saturation is described. It is an enrichment of the diagnostical possibilities in veterinary medicine. In the horse it is of great interest, because disturbances of the pulmonary gas exchange and the myocardial function are common in the anaesthetised horse, and reliable methods of assessing the cardiac output are rare. Using this monitoring technique in nearly 100 equine high risk patients facilitated insight into the complex changes of the pulmonary, cardiac and circulatory function in the anaesthetised horse. The registered data are the basis of the presented case reports. Values measured "behind the tissue" are influenced by the oxygen supply and the oxygen consumption within the periphery. Changes of the mixed venous oxygen status can be caused by a disturbance of the arterial oxygen status, by a insufficient performance of the cardiovascular system or by a change in metabolic activity. Being a multifactorial influenced parameter the mixed venous oxygen saturation can only be interpreted in connection with other parameters. The mixed venous oxygen status gives global information about the whole organism, but it is not able to inform about the oxygen supply of single organs. From our own personal experience it reflects an aggravation of the patient very early and reliable.

The purpose of this study was to review ventilation and postoperative analgesic technics in 137 dogs and 13 cats with congenital or acquired heart disease. The animals were referred to the Department of Veterinary Clinical Sciences at The Ohio State University, U.S.A, for the following surgical interventions: correction of patent ductus arteriosus (PDA-ligation, 28%), cardiac catheterization with angiogram and angioplasty (22%), pacemaker implantation (18%), exploratory lateral thoracotomy (8.7%), correction of right aortic arch ring anomaly (3.3%), correction of subvalvular aortic stenosis (2.7%), correction of PDA with coil in patients with mitral regurgitation and congestive heart failure (2%), pericardectomy and removal of heart base tumor (2%), and palliative surgery for ventricular septal defect (VSD, 0.7%). Controlled ventilation was used in all animals during thoracotomy. Anesthesia was maintained over 2.3 +/- 1.3 hours by using either isoflurane, halothane, propofol, or diazepam-ketamine in 64%, 32%, 2%, and 0.7% of animals, respectively. Postoperative analgesia was necessary in 20% of animals and was provided by using different technics over several hours. The technics and respective percentages of animals in which they were used, were: intravenous buprenorphine (3.3%), intercostal nerve blocks (8.7%), epidural morphine (4%), and interpleural regional analgesia (4%).

The study was done in order to investigate the central nervous activities in rabbits (n = 10) during experimental surgery in ketamine and ketamine/midazolam-anaesthesia. The combination of a benzodiazepine with ketamine was thought to be beneficial to reduce the usual excitatory nervous effects after ket amine-anaesthesia. The results of the measured EEG-power spectra and somatosensory-evoked potentials were presented. Additionally, the central effects were correlated with mean arterial blood pressure and the results of blood gas analyzes.

The purpose of this study was to review the effects of sedatives and anesthetics in 137 dogs and 13 cats with congenital or acquired heart disease which were referred for diagnostic, therapeutic, and surgical interventions: correction of patent ductus arteriosus (PDA-ligation, 28%), cardiac catheterization with angiogram and angioplasty (22%), pacemaker implantation (18%), exploratory lateral thoracotomy (8.7%), correction of right aortic arch (ring anomaly, 3.3%), correction of subvalvular aortic stenosis (2.7%), correction of PDA with coil in patients with mitral regurgitation and congestive heart failure (2%), pericardectomy and removal of heart-base tumors (2%), palliative surgery for ventricular septal defect (VSD, 0.7%), and sick patients with deleterious cardiac arrhythmias (0.7%). The anesthetic plan considered the risks of anesthesia based upon preoperative patient assessment, classification scheme for functional phases of heart failure, and anesthetic drug effects of the cardiovascular system. The effects of sedatives and anesthetic drugs on determinants of cardiac output are described. The most commonly used drugs for premedication, induction, and maintenance of anesthesia were midazolam-oxymorphone (20%), thiopental or etomidate (30%), and isoflurane (64%). Prompt therapy was given to control arrhythmias and provide organ perfusion, pain relief, muscle relaxation and renal diuresis, using lidocaine, dopamine, fentanyl, atracurium, and furosemide in 17.3% 14.7%, 12%, 10%, and 8.7% of animals, respectively. Methods of routine and advanced patient monitoring are described.

The purpose of this study was to review the incidence of cardiac arrhythmias in 137 anesthetized dogs and 13 anesthetized cats with congenital or acquired heart disease that were referred for correction of following procedures: patent ductus arteriosus (PDA-ligation, 28%), cardiac catheterization with angiogram and angioplasty (22%), pacemaker implantation (18%), exploratory lateral thoracotomy (8.7%), correction of right aortic arch (ring anomaly, 3.3%), correction of subvalvular aortic stenosis (2.7%), correction of PDA with coil in patients with mitral regurgitation and congestive heart failure (2%), pericardectomy and removal of heart base tumor (2%), and palliative surgery for ventricular septal defect (VSD, 0.7%). The anesthetic plan considered the risks of anesthesia based upon the pathophysiology of cardiac lesions and the anesthetic drug effects on the cardiovascular system. Recommendations are made for dogs with decreased cardiac contractility, cardiac disease with volume overload, cardiac disease with pressure overload, and pericardial tamponade. The percentages of animals and their associated cardiac arrhythmias after premedication and during and after anesthesia were: sinus bradycardia (15.3%), sinus tachycardia (3.3%), atrial flutter (0.7%), atrial fibrillation (0.7%), premature ventricular contraction (14%), and ventricular tachycardia (1.3%). Prompt therapy was given to a percentage of animals in order to control arrhythmia and support cardiovascular system, by using atropine or glycopyrrolate (14%), lidocaine (17.3%), and dopamine (14.7%).(ABSTRACT TRUNCATED AT 250 WORDS)

Two non-invasive continuous techniques for monitoring the respiratory function during anaesthesia have been established during the last year: pulse oximetry for monitoring the adequate oxygen supply and capnography for measuring the carbon dioxide elimination. In human medicine both are accepted as essential monitors with great reliability. Whether clinical use and interpretation can be transferred to animals without any restrictions will be discussed by looking on the physical and engineering background as well as the physiologic interpretation of the measured variable and their capability to detect critical events during administration of anaesthesia. Part I: Pulse oximetry measures the arterial oxygen saturation continuously and non-invasively. Its application in veterinary medicine must be discussed critically concerning the method as well as the interpretation. The information obtained is very different during injectable and inhalant anaesthesia. Respiratory depression is easy to detect while the animal breathes room air spontaneously. Is the inspired air enriched with oxygen, like during inhalant anaesthesia, normal values of oxygen saturation can mask the respiratory insufficiency and may give a false sense of security.

The object of this study was to evaluate minimal dose anesthesia with Tiletamine/Zolazepam for castration, dental treatments and other minor surgical procedures in cats. The study included 264 cats treated either at the Department of Veterinary Surgery, Ludwig-Maximilians University of Munich or under private practice conditions, in a small animal clinic in Hamburg (Germany). The drug dose needed for anesthesia for a 10 minute surgical procedure was calculated in each case using a formula. Side effects that occurred with doses recommended by the manufacturer could not be eliminated by decreasing the drug dose, but could be reduced considerably in severity and duration. Tiletamine/Zolazepam was found to be a useful drug for short anesthesia in cats at an average dose of 4.2 mg/kg.

The influence of short term anaesthesia with the N-methyl barbiturate Eunarcon on the pH and blood gases was investigated in 19 clinical healthy male castrated pigs of the breed Large White, three months old and with a mean body weight of 30 kg. The factors of oxygen in the blood--content, saturation of hemoglobin, O2 partial pressure--are diminished continuously during anaesthesia, with a decrease of pO2 on 77% of the initial value. The pCO2 increased, and the peak value of 11% above the initial level was seen already 10 minutes after starting the anaesthesia. The pH value like a seismograph of the ionic balance is not changed significantly. The results are discussed in connection with problems of medication and control of intravenous anaesthesia.

Electroencephalographic (EEG) recordings performed in piglets during Trapanal anaesthesia showed distinct changes in bioelectrical brain activity in some piglets when castration was carried out. Only an additional extradural anaesthesia seemed to interrupt the transmission of peripheral pain stimuli to the central nervous system. Based on the protocol used EEG did not reveal a marked response to noxious stimulation. Castration of piglets up to two weeks of age were performed during general anaesthesia with Trapanal or Disoprivan or local anaesthesia with Hostacain or without any anaesthesia. The different modes of anaesthesia have had no effects to postoperative wound healing and weight gain between groups as well as between males and females within single groups. With regard to insufficient analgesia and/or partially extreme secondary effects the application of investigated anaesthetic methods on the occasion of castration of piglets is not justifiable at present. Castration in piglets up to an age of two month without anaesthesia is allowed by the animal protection law. However, due to improved wound healing and decreased response to surgical stimulus we suggest to perform castration during the first 10 days after delivery.

The halothane test was performed under different conditions in 10 halothane-sensitive growing pigs (Landrace, line 01). Haematological and metabolic changes in blood were monitored during the handling of the pigs before the test, during the exposure to halothane and thereafter. Already in connection with the catching and fixation of the pigs, the levels of haemoglobin in blood, and of glucose, lactate and potassium in plasma increased significantly. However, the concentration of glycerol was not raised before the occurrence of the malignant hyperthermia. While the level of potassium decreased already from the beginning of the halothane exposure until the development of symptoms, the values of haemoglobin, glucose and lactate continued to increased. The level of the free fatty acids did not show any changes during the experimental period. An infusion of phentolamine reduced the increase of haemoglobin and potassium and an infusion of propranolol reduced the increase of haemoglobin and glycerol significantly, without any effect on the result of the halothane test. By an anaesthesia, starting 30 minutes before the exposure to halothane, the development of the typical halothane reaction was obviated for at least 10 minutes. Observed metabolic changes during a simultaneous epinephrine administration were exclusively due to its adrenergic effects.

Study in ECGs of a clinical collection of 45 dogs (15 dogs without heart disease and without sedation or anesthesia, 15 dogs with acquired and congenital heart disease without sedation or anesthesia, 15 dogs premedicated and anesthetised and all dogs except one without heart disease). Especially studied were the parts which are known in the ECG of the dog as variable and labile (ST-segment, ST-segment-junction and the T-wave). In the group of premedicated and anesthetised dogs a curved and arched ST-segment was more often observed as in comparison to the other two groups. On the other hand the ECG evaluations showed that in all studied groups independent of the status of the heart many similar or equal configurations of the variable and labile parts of the ECG were observed.

The consecutive steps in anaesthesia management of polytraumatized dogs and cats are described. First of all care must be taken of the respiration, the cardiovascular circulation and the central nervous system. Analgesia plays an important role even at this stage. After stabilizing vital functions in the phase of primary care, cautious anaesthesia management is required for life-saving surgical procedures in the phase of secondary care. Modified balanced anaesthesia has been well proven in polytraumatized small animal patients.

In reptiles anesthesia is recommended not only for painful treatment but also for diagnostic procedures like radiology, sonography, endoscopy and MRI. Special attention should be directed to the anesthetic regimen because of anatomical and physiological differences to mammals. To achieve optimum body temperature (normally 25-30 degrees C) preanesthetic heating is useful. In most cases ketamine hydrochloride is used as an injectable anesthetic. Our own anesthesias (n = 263) are compared to those in the literature. Important disadvantages are species-specific dosages between 15 and 220 mg/kg body weight and poor relaxation. The results of 132 anesthesias performed by the authors using Isoflurane are discussed with reference to the literature. The main advantages were independence of species-specific problems and excellent analgesia and relaxation. Due to total relaxation, manual intermittent positive-pressure ventilation (IPPV) is necessary.

The injection anaesthetic propofol (Disoprivan) was used in 85 cats for performing gastroduodenoscopy. Anaesthesia and feasibility for executing endoscopy were evaluated. Two cats suffered from a transient (30 sec) respiratory arrest. In any other cases stable cardiovascular and acceptable respiratory conditions were observed. The endoscopy was easy to perform and no emesis was induced. Anaesthesia of the cat with propofol can be very well controlled. It is characterised by gentle induction and a recovery free from excitation.