A clinical trial was undertaken using three different inhalant anaesthetic agents and one intravenous anaesthetic agent in dogs undergoing routine desexing surgery. Healthy adult dogs undergoing either ovariohysterectomy or castration were assessed as to their demeanour, with the more excitable dogs being placed in groups receiving premedication with acepromazine and morphine. All dogs were then randomly assigned an anaesthetic agent for induction of general anaesthesia. The agents were the inhalants halothane, isoflurane and sevoflurane, and the intravenous agent propofol. Inhalant inductions were undertaken using a tight fitting mask attached to a standard anaesthetic machine with a rebreathing circuit, with the maximum dose of inhalant available from a standard vaporiser. Propofol inductions were undertaken via intravenous catheter. Dogs induced with propofol were randomly assigned one of the three inhalant agents for maintenance. Those induced by inhalant agent were maintained using the same agent. The surgical procedure was undertaken in standard fashion, as was recovery from anaesthesia. All dogs received the non-steroidal anti-inflammatory agent meloxicam. Data collection was divided into three stages: induction, maintenance, and recovery from anaesthesia. Variables measured at induction of anaesthesia were time to intubation, number of intubation attempts, tolerance of mask, quality of induction and quality of transfer to the maintenance stage. Standard variables for monitoring of anaesthesia were recorded throughout the maintenance of anaesthesia. Variables measured at recovery were time to righting, time to standing and quality of recovery. The mean time to intubation when using the newer inhalant sevoflurane (196.2 � 14.8sec, mean � SE) was not significantly different to that for halothane (221.4 � 14.0sec) or isoflurane (172.4 � 15.0sec). Time to intubation with isoflurane was significantly faster than with halothane. Mean time to intubation with propofol (85.4 � 7.7sec) was significantly faster than that for any of the three inhalants. Choice of inhalant had no effect on quality of induction. The use of premedication significantly improved the quality of induction. The use of propofol for induction likewise significantly improved the quality of induction. Standard cardiorespiratory variables measured during the maintenance phase of anaesthesia remained within normal clinical ranges for all three inhalants, and were therefore not further analysed. Choice of inhalant agent had no significant effect on the time to righting or standing in recovery. The use of propofol for induction had no effect on these variables. Animals placed in groups receiving premedication had significantly longer times to righting and standing. The oesophageal temperature at the end of the procedure had a significant effect on times to righting and standing, with lower temperatures contributing to slower recoveries. Independent of procedure time, male dogs had shorter times to righting than female dogs.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2005. / Härtill 5 uppsatser.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2008. / Härtill 4 uppsatser.

Orientador: Newton Nunes / Banca: Juliana Noda Bechara Belo / Banca: Paulo Sérgio Patto dos Santos / Banca: Carlos Augusto Araújo Valadão / Banca: José Antonio Marques / Resumo: Avaliaram-se os efeitos da infusão contínua de propofol em associação ao fentanil ou sufentanil sobre a hemodinâmica, eletrocardiografia e índice biespectral em cadelas submetidas à ovariosalpingo-histerectomia. Para tal, foram utilizadas 20 cadelas hígidas, induzidas à anestesia geral com 10 mg/kg de propofol. Após a intubação com sonda orotraqueal de Magill, receberam suporte ventilatório com oxigênio a 100% e fluxo de 15 mUkg/min em circuito fechado, ciciado no modo pressão controlada, mantendo-se a ventilação a pressão positiva intermitente. A manutenção anestésica foi realizada com a administração de O,4mglkglmin de propofol e foram distribuídos em dois grupos de 10 animais que receberam 5J,lglkg de fentanil (GPF) ou 1J,lg/kg de sufentanil (GPS) por via intravenosa, seguida de infusão contínua... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Possible effects of the continuous infusion of propofol associated with fentanyl or sufentanil on haemodynamic, blood gas analysis, electrocardiography and bispectral index in female dogs, submitted to the surgical procedure of ovariosalpingohysterectomy, were evaluated. Twenty healthy female dogs were used and general anesthesia was induced with 10mglkg of propofol. They received ventilatory support with 100% oxygen and a 15 mUkg/min flow in a cIosed circuit, cycled with controlled pressure. Ali animais were submitted to total intravenous anesthesia with propotol (O.4mg/kglmin) and distributed in two groups of ten animais each one. They received 5J.1glkg of fentanyl (GPF) or 1J.1g1kg of sufentanil... (Complete abstract click electronic access below) / Doutor

Abstract The number of ambulatory surgical procedures is increasing throughout the world. This is partly due to the development of a number of new anaesthetic, analgesic and adjuvant drugs, each with more rapid onset and shorter duration of action, over the past two decades. An interest in the issues discussed in this thesis arose out a desire to improve the quality of anaesthesia for patients who undergo day-case surgery. A second aim was to compare the different anaesthetic methods in terms of recovery from anaesthesia and costs. A total of 233 patients undergoing day-case knee arthroscopy under either 2% or 5% lidocaine spinal anaesthesia or general anaesthesia with desflurane, isoflurane, propofol or sevoflurane were investigated in two prospective, randomised clinical trials. The overall aims were to find the most suitable, satisfactory and economically feasible method for adult ambulatory knee arthroscopy and to assess the factors that affect the immediate postoperative period and the one-week recovery profile at home. The patients were highly satisfied with all the methods of anaesthesia. There was a slight tendency in favour of general anaesthesia compared to spinal anaesthesia. The general level of pain after ambulatory knee surgery was low after the first few hours postoperatively and continued to be low during the first postoperative week. After short-acting general anaesthesia with desflurane, isoflurane and propofol, home readiness was achieved over two hours earlier than after 5% lidocaine spinal anaesthesia. Home readiness was significantly delayed after 2% lidocaine spinal anaesthesia compared to sevoflurane inhalation anaesthesia. General anaesthesia with isoflurane was cheaper than the other general anaesthetics, i.e. desflurane, sevoflurane, propofol, or 2% and 5% lidocaine spinal anaesthesias. Propofol anaesthesia was the most expensive. The spinal anaesthesia patients had a higher incidence of headache, backache and lower leg pain during the first postoperative week than the patients who had had general anaesthesia. In busy ambulatory surgery units, remarkable savings may be achieved by using short-acting general anaesthetics, i.e. desflurane and isoflurane, instead of propofol or sevoflurane general anaesthesias or lidocaine spinal anaesthesia. This is due to the lower costs of desflurane and isoflurane compared to sevoflurane and propofol and the shorter time needed for postoperative care compared to spinal anaesthesia.

This dissertation focuses on the use of near-infrared spectroscopy (NIRS) to identify trends in regional cerebral oxygen saturation (rSO2) in both conscious and anaesthetised healthy horses. A cerebral/somatic oximeter sensor recorded rSO2 from the dorsal sagittal sinus of 6 healthy horses. Values for rSO2, arterial and venous oxygen and carbon dioxide tensions (PaO2, PvO2, PaCO2 and PvCO2 respectively), along with arteriovenous oxygen saturations (SavO2) were recorded in unsedated (recording period [RP] 1), sedated (RP2), and anaesthetised horses (RP3-5); and during recovery (RP6-8). During anaesthesia, horses were ventilated to achieve states of normo- (RP3), hyper- (RP4) and hypocapnoea (RP5). Overall mean ± s.d. values for rSO2, PaO2, PvO2, PaCO2, SavO2 and mean arterial pressure (MAP) varied significantly by RP. Significant decreases in rSO2 were identified between RP1 and the post-anaesthetic periods however no significant differences in rSO2 values were identified between RP1 and the intra-anaesthesia periods. Regional cerebral oxygen saturation was significantly correlated with PaO2, PvO2 and SavO2. No correlation was identified between rSO2 and lactate concentration. This is the first study to identify trends in rSO2 in horses using NIRS. A significant positive correlation was identified between rSO2 and PvO2, suggesting that alterations in cerebral oxygenation may be reflected in jugular PvO2. Results of this study demonstrate that NIRS can be used during general anaesthesia to monitor trends in rSO2 in healthy horses, and has the potential to alert clinicians to cerebral desaturation events when used in a clinical setting. / Dissertation (MMedVet)--University of Pretoria, 2013. / gm2014 / Companion Animal Clinical Studies / unrestricted

Objectives To compare the anaesthetic, analgesic and cardiorespiratory effects of intramuscular medetomidine and ketamine administered alone or combined with morphine or tramadol for orchiectomy in cats. Study design Randomised, blinded, prospective clinical study. Animals Thirty client owned healthy cats. Materials and methods Cats received a combination of medetomidine (60 μg kg-1) and ketamine (10 mg kg-1) alone (MedK) or combined with morphine (0.2 mg kg-1) (MedKM) or tramadol (2 mg kg-1) (MedKT) intramuscularly. Time of different events and physiological parameters were recorded by a blinded researcher. Pre-surgery arterial and venous blood gases were measured. Heart rate (HR), respiration rate (fR), systolic arterial blood pressure (SABP), peripheral haemoglobin saturation (SpO2) and end-tidal carbon dioxide tension (PETCO2) were recorded every 5 minutes of general anaesthesia and at each surgical stage. Post-operative analgesia was evaluated with a visual analogue scale, a multidimensional composite scoring system and a rigid tip von Frey mechanical threshold device every hour from 3 to 8 hours post-injection of the initial combination of drugs. Data were analysed with a linear mixed model, Kruskal Wallis or Chi-square tests (p < 0.05). Results Median (range) induction and recovery times (minutes) were not significantly (P = 0.125) different among the three combinations: 5.6 (2.7, 8.0), 7.4 (5.1, 9.6) and 8 (5.8, 14.9) for induction and 128 (95, 143), 166 (123, 210) and 143 (123, 180) for recovery, with MedK, MedKT and MedKM, respectively. All three combinations caused similar low partial pressure of arterial oxygen (PaO2) values (mean ± SD: 66.2 ± 1.7 mmHg). Surgery had a significant effect on SABP (p < 0.001), SpO2 (p < 0.001), fR (p = 0.003) and HR (p = 0.002), which increased; and PETCO2 (p = 0.003), which decreased, with all combinations. Non-significant differences were found in pain scores and von Frey results among treatments; however, the von Frey changes over time did vary by treatment (p < 0.001) with the MedK group returning to baseline values more rapidly than MedKM and MedKT. None of the cats required rescue analgesics. Conclusion and clinical relevance All three protocols provide adequate anaesthesia and analgesia for orchiectomy in cats. However, rescue intervention to maintain surgical anaesthesia such as isoflurane may be required in some cats. Oxygen should be supplemented. / Dissertation (MMedVet)--University of Pretoria, 2013 / gm2014 / Companion Animal Clinical Studies / unrestricted

A large proportion of dogs undergoing computed tomography are anaesthetised and receive concurrent supplementary oxygen. Both factors promote the development of pulmonary atelectasis, which may mask or mimic lung pathology and compromise image quality, which is of concern to the radiologist. The aim of the study was firstly to determine whether significant atelectasis would develop using a commonly employed anaesthetic protocol in a typical hospital setting, especially where dogs may have been anaesthetised in lateral recumbency prior to scanning. Secondly, to determine whether a change in body position to sternal recumbency would be sufficient to resolve atelectasis. Six healthy adult Beagles were anaesthetised in sternal recumbency and using a breath-hold technique, baseline helical transverse thoracic images were acquired. Dogs were then placed in either right or left lateral recumbency for 30 minutes, with scans performed at predetermined lung lobe locations and time intervals. Dogs were then repositioned in sternal recumbency for a further 20 minutes, with similar scans performed. The study was repeated two weeks later in the opposite lateral recumbency. Changes in Hounsfield units and cross-sectional area of all lung lobes were measured. Lateral recumbency did not result in true atelectasis in healthy Beagles of normal body condition. Infrequently, patchy increased attenuation, which failed to resolve completely during sternal recumbency, was visualised in the left cranial lobe during left lateral recumbency. The degree of attenuation changes in healthy Beagles was minimal, and thus if dogs were anaesthetised in lateral recumbency prior to computed tomography, this should not preclude scanning. / Dissertation (MMedVet)--University of Pretoria, 2016. / Companion Animal Clinical Studies / MMedVet / Unrestricted

Die größte Angst eines Patienten während einer Operation ist es, den Eingriff bewusst mitzuerleben oder sogar Schmerzen wahrzunehmen. Mit der Möglichkeit, den Menschen während einer Operation gesteuert in die Bewusstlosigkeit zu führen, galt deshalb ein großes Maß der Aufmerksamkeit des Anästhesisten, dieses Trauma zu vermeiden. Anfangs waren zur Beurteilung nur Herzfrequenz- oder Blutdruckanstieg interpretierbar. Mit Entwicklung des EEG sowie fortschreitender Computertechnik wurden in den letzten 10 Jahren prozessierte Parameter aus dem nahezu chaotisch aussehenden EEG abgeleitet – diese erlauben unter Messung der vorliegenden Hirnrindenaktivität Rückschlüsse auf die Narkosetiefe. Dieser Beitrag stellt Möglichkeiten, aber auch Grenzen der Verfahren zur Messung der Narkosetiefe vor. Zudem wird ein Ausblick auf möglicherweise bald anwendbare neue Techniken gegeben. / Most patients fear a situation in which they remain aware of ongoing surgery, or even perceive intense pain, despite anaesthesia. Ever since the possibility to perform anaesthesia has existed, great efforts have been invested to eliminate the possibility of such a misfortune. Initially, only clinical signs of awareness, such as an increase in heart rate or blood pressure, could be used to assess the depth of anaesthesia. Since the development of electroencephalography (EEG), and with the advances in computer technologies, a number of processed parameters can be derived from EEGs and are able to minimise the risk of such occurrences. In the present article, the different approaches are described together with potential limitations. In addition, an outlook is presented to identify future technologies able to detect awareness during anaesthesia.

Background: Simulation-based education (SBE) has been shown to be an effective and reproducible learning tool. SBE is used widely internationally. The current state of SBE in South Africa is unknown. To the best of our knowledge this is the first survey that describes the use and attitudes towards SBE within South Africa. Methods: An online survey tool was distributed by email to: i) the South African Society of Anaesthesiologists (SASA) members; and ii) known simulation education providers in South Africa. The respondents were grouped into anaesthesia and non-anaesthesia participants. Descriptive statistics were used to analyse the data. Ethics approval was obtained: HREC REF 157/2017. Results: The majority of the respondents provide SBE and integrate it into formal teaching programmes. There is a will amongst respondents to grow SBE in South Africa, with it being recognised as a valuable educational tool. The user groups mainly targeted by SBE, were undergraduate students, medical interns, registrars and nurses. Learning objectives targeted include practical skills, medical knowledge, critical thinking and integrated management. Amongst anaesthesia respondents: the tool most commonly used to assess the quality of learner performance during SBE, for summative assessment, was ‘expert opinion’ (33%); the most frequent methods of evaluating SBE quality were participant feedback (42%) and peer evaluation (22%); the impact of SBE was most frequently assessed by informal discussion (42%) and learner feedback (39%). In anaesthesia SBE largely takes place within dedicated simulation facilities on site (47%). Most respondents report access to a range of SBE equipment. The main reported barriers to SBE were: finance, lack of trained educators, lack of equipment and lack of protected time. A limited number of respondents report engaging in SBE research. There is a willingness in both anaesthesia and non-anaesthesia groups (96% and 89% respectively) to collaborate with other centres. Conclusion: To the best of our knowledge this publication provides us with the first cross sectional survey of SBE in anaesthesia and a selection of non-anaesthetic respondents within South Africa. The majority of respondents indicate that SBE is a valuable education tool. A number of barriers have been identified that limit the growth of SBE within South Africa. It is hoped that with a commitment to ongoing SBE research and evaluation, SBE can be grown in South Africa.