Perianesthesia analgesia, recovery efficacy, and financial impact of ultrasound-guided lumbar plexus and sciatic nerve analgesia in dogs undergoing tibial plateau leveling osteotomy

Includes bibliographical references.2022 Fall.Perioperative analgesia is critical for patients undergoing surgery because uncontrolled pain can result in deleterious consequences and predispose chronic pain. Therefore, developing an appropriate analgesia technique is crucial, and in this study, an analgesia protocol was investigated in dogs undergoing tibial plateau leveling osteotomy (TPLO). The TPLO is a surgical technique used to stabilize the stifle joint for treating cranial cruciate ligament disease. This surgical procedure is invasive and painful. Therefore, multimodal analgesia is often required for controlling pain associated with TPLO surgery. This study used ultrasound-guided regional anesthesia of the lumbar plexus and sciatic nerve as a component of multimodal analgesia to control perioperative pain compared to patients only receiving a standard systemic analgesia. The study was designed to evaluate the efficacy of regional anesthesia and to determine the financial impact of this additional multimodal procedure. We hypothesized that ultrasound-guided lumbar plexus and sciatic nerve blocks would provide a better analgesic effect intraoperative and postoperatively. The second part of the study we hypothesized that ultrasound-guided lumbar plexus and sciatic nerve blocks would increase the anesthesia cost. It would then be possible to determine a cost – benefit of the procedure. The study was designed as a prospective, randomized, blinded clinical trial. Twenty dogs underwent TPLO surgery were enrolled in the study and randomly assigned to regional analgesia (RA) or control (CON) group. Dogs in the RA group received 0.5% ropivacaine for ultrasound-guided lumbar plexus and sciatic nerve blocks. The total dose of ropivacaine for both blocks was 0.15 mg/kg. Dogs in the CON group received sterile 0.9% saline for the blocks. All dogs received 0.2 mg/kg of hydromorphone and 0.02 mg/kg of atropine for anesthesia premedication. Propofol was administered for anesthesia induction to perform endotracheal tube intubation. Isoflurane in oxygen was delivered using a circle rebreathing system to maintain anesthesia. The ultrasound-guided lumbar plexus and sciatic nerve blocks were performed prior to TPLO surgery. Fentanyl was used for intraoperative as rescue analgesia to reduce the response from surgical stimulation or with an increase in heart rate, respiratory rate, or mean arterial blood pressure. Isoflurane was adjusted to maintain the appropriate anesthesia plane. Hypotension was treated following a stepwise protocol, in a sequencing fashion. The treatment protocol was added until the complications was resolved. The treatment protocol started from decreased isoflurane vaporizer setting, lactate Ringer's solution bolus, hetastarch bolus, and dopamine administration. At extubation, the recovery quality and pain were evaluated. Dexmedetomidine was used to treat poor recovery quality and pain. During the postoperative 12 hours period, pain and recovery quality were assessed by Colorado State University acute pain scale, visual analog pain scale, and modified University of Melbourne pain scale. Fentanyl or methadone was used for postoperative rescue analgesia. Dexmedetomidine or acepromazine was administered to calm the patient. The amount of every drug used, complications management, and extra nursing care were recorded to evaluate the blocks' efficacy. The micro-costing technique was used to collect the financial data and was analyzed to determine the financial impact. In the clinical study, there was a statistically significant difference in the amount of intraoperative fentanyl administered for rescue analgesia between the groups (p = 0.02), with lesser doses given to the RA group. Hypotension was found in 40% of dogs in the RA group and 80% of the dogs in the CON group (p = 0.16). Dogs in the RA group required less intensive treatment than in the CON group. There was a statistically significant difference in the recovery scores between the groups, with those in the RA group having lower recovery scores (p = 0.04). In the postoperative period, the time to receive the first dose of rescue analgesia for dogs in the RA group was longer than dogs in the CON group (p=0.04). Micro-costing method was used for collecting the monetary information. The cost analysis was performed for evaluating the costs of dogs that received ultrasound-guided regional anesthesia with 0.5% ropivacaine and 0.5% sterile saline. The anesthesia fixed cost for the surgery was US$354. There was a statistically significant difference between the variable costs, with the RA group (US$82.65 (69.15-94.56); median (min-max)) having less anesthesia variable costs than dogs in the CON group (US$125.8 (55.23 to 156.35); p = 0.02). The additional cost for a charge per service of the use of ultrasound and electro-nerve stimulator machines (US$26.62) affects the total anesthesia cost for the RA group into both direction, it can enhance and save the total anesthesia cost. It can increases the total anesthesia cost by $US40.54 per dog and it can save the total anesthesia cost by$US35.17 per dog. From the clinical perspective, the number of dogs receiving TPLO surgery at the study hospital is approximately 160 cases per year. This number was used for estimating cost benefit per year performing nerve blocks for TPLO surgery and found that the nerve blocks would potentially increase the total cost for 160 dogs to US$6,486.40 per year but would decrease the total anesthesia cost by US$5,627.20 per year. Ultrasound-guided lumbar plexus and sciatic nerve regional analgesia was found to be an effective multimodal analgesia for TPLO surgery. The technique provided effective intraoperative analgesia that decreased rescue analgesia during surgery and led to better recovery from anesthesia for the dogs in this study. The ultrasound-guided analgesia technique would increase anesthesia costs but better analgesia, anesthesia, and decreased complications provided significant cost-saving benefits when performing regional analgesia for TPLO surgery

Evaluation of an automatic urinometer including use of silicone oil to decrease biofilm formation due to proteinuria, hemoglobinuria and bacterial growth

Background: A new capacitance-based automatic urinometer (AU) facilitates continuous urine output (UO) measurement, which may help to predict and diagnose acute kidney injury (AKI). To prevent mismeasurement due to bacterial, albumin or free hemoglobin biofilm, a water-soluble capsule with silicone oil has been integrated in the device. Aims: To assess: the performance of a new capacitance-based AU in adult patients in a cardiothoracic intensive care unit (ICU) and compare it with a manual urinometer (MU) in regard of bias, precision, temporal deviation and to evaluate the staff’s opinion of the AU (Study I); a modified capacitance-based AU in comparison with an MU regarding measuring bias among patients ≤10 kg in a pediatric intensive care unit and to evaluate the staff’s opinion of the AU (Study II); whether a silicone oil-coated polypropylene plastic surface, as used in an AU, may reduce early microbial biofilm formation and to identify the silicone oil target; to compare polypropylene with polystyrene and low with medium viscosity silicone oil regarding the propensity to impede biofilm formation (Study III); if silicone oil added to the measuring chamber of the AU may prevent the rise in capacitance due to albumin or free hemoglobin biofilm, allowing the device to function for longer periods of time (Study IV). Methods: Study I-II were prospective observational cohort studies, whereas Study III-IV were experimental prospective in vitro studies. Study I: 34 postoperative patients had their hourly UO registered with either an AU (n=220) or an MU (n=188), which were validated by cylinder measurements and analyzed using the Bland-Altman method. The temporal deviation of the MU measurements was recorded (n=108) and at the end, the nursing staff (n=28) evaluated the AU. Study II: The hourly diuresis was measured using either an AU (n=127) or an MU (n=83) in 12 children (weight ≤10 kg) and validation was carried out using a measuring cylinder. Thereafter, the nursing staff (n=18) evaluated the AU. Study III: Clear flat-bottomed wells of either polypropylene or polystyrene were pretreated with silicone oil of low or medium viscosity, after which a panel of microbes, including common uropathogenic bacteria and Candida albicans, were added. The plates were left for 3 days and the amount of biofilm formation was assessed using the crystal violet assay. Study IV: A solution of Ringer’s acetate mixed with either albumin or free hemoglobin was run through an AU with either a water-soluble capsule with silicone oil (n=20) or not (n=20) and the derived 400-500 capacitance measurements, respectively, were retrieved from the AU device and analyzed. Results: Study I: The AU had a smaller mean bias (+1.9 mL) than the MU (+5.3 mL) (p<0.0001). Defined by their limits of agreements (±15.2 mL AU vs. ±16.6 mL MU, p=0.11), the measurement precision of the two urinometers were similar. The AU had inherently no temporal deviation, whereas the mean temporal deviation of the MU was ±7.4 minutes (±12.4%) (p<0.0001). The nursing staff rated the AU significantly higher than the MU in terms of user-friendliness, measuring reliability, efficacy and safety. Study II: The AU and the MU had a mean bias of −1.1 mL (CI, -0.6 to -1.5) and -0.6 mL (CI, ±0.0 to -1.2) respectively (p=0.21). The participating staff considered the AU significantly easier to learn, use and handle compared with the MU. Study III: Polypropylene plastic exhibited less biofilm growth than polystyrene. Silicone oil, irrespective of viscosity, significantly decreased biofilm formation by common uropathogenic bacteria, including ESBLproducing and multi-drug resistant strains, as well as C. albicans. E. coli curli fimbriae were established as the main focus of silicone oil. Study IV: The mean increase in capacitance with albumin 3 g/L group was 257±96 without and 105±32 with silicone oil, respectively, during 24 hours. After ten hours of registration, differences between the two albumin groups reached statistical significance. For the free hemoglobin groups (0.01 g/L), the mean increase in capacitance was 190±174 with silicone oil and 324±78 without. A significant difference between the free hemoglobin groups was seen after 20 hours and onwards. Conclusions: For adult postoperative patients, the AU was non-inferior to the MU with regard to measuring precision and significantly better than the MU in terms of bias and temporal deviation (Study I); for children weighing ≤10 kg, the urinometers were comparable in performance (Study II); staff consistently appraised the AU significantly higher than the MU in terms of user-friendliness, reliability, safety and efficacy (Study I and II). Both low and medium viscosity silicone oil coating of a polypropylene surface decreased biofilm formation from common uropathogenic bacteria including Candida albicans and the biofilm-promoting factor curli fimbriae was identified as a plausible target (Study III); coating of the capacitance measurement membrane of the AU by albumin or free hemoglobin significantly disturbed the capacitance measurement capability of the AU, and this could be prevented by incorporating silicone oil in the device (Study IV)

Characterization of oral pain in cats after dental extractions in a multidisciplinary approach

Les maladies bucco-dentaires sont fréquemment rapportées en médecine vétérinaire et le traitement généralement nécessite l’extraction des dents. Cependant, la procédure est invasive et une évaluation à long terme ainsi qu’une gestion de la douleur sont nécessaires. En médecine vétérinaire, les opioïdes, les blocs anesthésiques locaux et les anti-inflammatoires non stéroïdiens sont administrés en intervention analgésique péri-opératoire. Par exemple, la buprénorphine est un opioïde analgésique puissant, hautement lipophile, et est principalement utilisé pour traiter la douleur aiguë. La buprénorphine est souvent administrée dans le cadre d'une analgésie multimodale. Les signes comportementaux de la douleur induite par les maladies bucco-dentaires n'ont pas été systématiquement étudiés chez les chats, et les connaissances actuelles sont principalement basées sur des preuves anecdotiques ou des études réalisées chez d'autres espèces. On ignore comment les maladies bucco-dentaires et le traitement (c'est-à-dire l'extraction dentaire) peuvent affecter la prise alimentaire péri-opératoire, les scores de douleur, les besoins analgésiques supplémentaires et les comportements chez les chats. En outre, il serait important de savoir si l’échelle de douleur basée sur l'expression faciale (Feline Grimace Scale: FGS) pourrait également être utilisée pour l'évaluation de la douleur buccale. Les objectifs du projet étaient 1) d'identifier les comportements spécifiques associés aux maladies bucco-dentaires en utilisant une évaluation par vidéo, et de les corréler aux scores de la douleur en temps réel, 2) d'évaluer l'impact des maladies bucco-dentaires et de la douleur sur la prise alimentaire et les comportements liés à l'alimentation, 3) de déterminer les effets du traitement des maladies bucco-dentaires sur le comportement, les scores de la douleur et la prise alimentaire, 4) d’évaluer la fiabilité inter-évaluateurs du FGS et 5) pour évaluer l'efficacité analgésique et les événements indésirables d'une formulation à haute concentration de formulation de chlorhydrate de buprénorphine (Simbadol, 1,8 mg / mL) en comparaison avec une formulation standard de chlorhydrate de buprénorphine (Vetergesic, 0,3 mg / mL) dans le cadre d'un schéma multimodal chez les chats subissant des extractions dentaires. Les hypothèses étaient que 1) des comportements spécifiques pourraient être identifiés et corrélés aux scores de la douleur en temps réel, 2) les chats atteints d'une maladie bucco-dentaire sévère auraient une consommation alimentaire plus faible et des scores de douleur plus élevés et nécessiteraient une analgésie de secours comparativement aux chats qui ne sont pas / minimalement atteints par une maladie bucco-dentaire, 3) le traitement des maladies bucco-dentaires réduirait la prévalence des comportements spécifiques ainsi que les scores de douleur et améliorerait la consommation alimentaire de ces animaux, 4) les scores FGS notés par différents évaluateurs seraient fiables et 5) Simbadol et Vetergesic produiraient tous deux des scores de douleur postopératoire, des événements indésirables, ainsi que le moment et la prévalence de l'analgésie de secours similaires lors de l'utilisation du Glasgow Composite Measure Pain Scale-Feline (CMPS-F). Le projet a été divisé en deux études et quatre articles (étude 1: articles 1 à 3, étude 2: article 4): 1) article sur le score de la douleur, les besoins en analgésie de secours et la quantité de nourriture ingérée chez les chats subissant un traitement oral, 2) article sur les comportements spécifiques induits par la douleur liés à la douleur buccale chez les chats sous traitement oral, 3) article sur la fiabilité inter-évaluateurs de la FGS chez les chats sous traitement oral, et 4) comparaison détaillée de l'efficacité analgésique de deux schémas posologiques en utilisant deux concentrations différentes de buprénorphine chez les chats subissant des extractions dentaires. Dans le premier article, vingt-quatre chats ont été répartis également en deux groupes: un groupe qui représente des maladies bucco-dentaires légères (traitement dentaire minimal) et un autre sévères (extractions dentaires multiples) sur la base d'un système de notation dentaire qui impliquait le nombre et l'emplacement de l'extraction des dents et hospitalisés pendant 7 jours (admission au jour 0, examen bucco-dentaire, radiographies et traitement sous anesthésie générale le jour 1 et sortie le jour 6). Pendant l'hospitalisation, les scores de douleur basés sur l'échelle composite de Glasgow (CMPS-F), la prévalence de l'analgésie de secours (CMPS-F ≥ 5/20), la prise d'aliments secs et mous (%) pendant 3 minutes et 2 heures, l'apport quotidien d'aliments mous et les cytokines inflammatoires sériques ont été analysés. Dans le deuxième article, les chats ont été filmés à distance pendant 10 min tout au long de l'étude à différents moments (au total 36h d'enregistrement vidéo). Les vidéos se composaient de quatre parties soit les comportements généraux, de jeu, d'alimentation et post-alimentation. La durée et la fréquence des différents comportements basés sur un éthogramme ont été analysées. Dans le troixième article, quatre-vingt-onze captures d'images (c'est-à-dire des captures d'écran) à partir de vidéos filmées aux jours 1 (postopératoire 6 heures) et 6 pour l'article 2 et des vidéos filmées avant / après l'analgésie de sauvetage ont été incluses. Le FGS comprend cinq unités d'action (AU): les yeux, les oreilles, le museau, les moustaches et la position de la tête. Les scores FGS des images ont été évalués indépendamment par quatre évaluateurs en aveugle. La fiabilité inter-évaluateurs de chaque score AU et FGS total et l'effet de la présence du soignant ont été évalués. Dans l'étude 2 (article 4), vingt-trois chats subissant des extractions dentaires ont été inclus. Les chats ont reçu aléatoirement soit Simbadol (1.8 mg/mL; 0.24 mg/kg SC, toutes les 24 heures, n = 11) ou Vetergesic (0.3 mg/mL; 0.02 mg/kg IM, toutes les 8 h, n = 12) tout au long de l'étude. Ils ont été admis au jour 0, ont subi un examen oral, des radiographies et un traitement sous anesthésie générale le jour 1 et ont été libérés le jour 4. La sédation et la douleur ont été évaluées à l'aide de l'échelle visuelle analogique interactive dynamique (jour 1) et CMPS-F, respectivement. Les scores de sédation, de douleur et la prévalence de l'analgésie de secours (CMPS-F ≥ 5/20) et du ressentiment (défini comme tout type de comportement d'évitement associé à l'aversion pour l'administration de médicaments) ont été analysés statistiquement. Les études ont montré que les scores de la douleur et la prévalence de l'analgésie de secours étaient significativement élevés, ainsi que les apports d'aliments secs et mous étaient significativement diminués chez les chats atteints d'une maladie grave par rapport à ceux présentant une maladie légère. De surcroit, la maladie buccale influence les cytokines inflammatoires et induit des comportements. Par ailleurs, Le FGS est un outil fiable pour l’évaluation de la douleur buccale et n’est pas affecté par la présence du soignant. En outre, les scores de la douleur et la prévalence de l'analgésie de secours chez les chats auxquels Simbadol a été administré n'étaient pas significativement différents de ceux administrés par Vetergesic. De plus, certains chats administrés par Vetergesic ont développé un ressentiment à l'égard de l'administration du médicament, qui n'était pas significativement différent de ceux administrés par Simbadol. Une analgésie à long terme est nécessaire après des extractions dentaires chez les chats atteints d'une maladie bucco-dentaire sévère. La diminution de l'apport alimentaire et les comportements spécifiques identifiés dans les études pourraient être utilisés pour différencier entre les chats douloureux des chats indolores dans la pratique clinique. Le FGS est un outil fiable pour l'évaluation de la douleur chez les chats subissant des extractions dentaires. Simbadol a produit des effets analgésiques similaires à Vetergesic sans induire un ressentiment pendant l'administration du médicament.Oral disease is one of the most commonly reported diseases in veterinary medicine, and tooth extractions are commonly required as the treatment. The procedure, however, is invasive, and long-term pain management is necessary. In veterinary medicine, opioids, local anesthetic blocks and nonsteroidal anti-inflammatory drugs are administered as perioperative analgesic intervention. Behavioral signs of oral disease-induced pain have not been systematically investigated in cats, and the current knowledge is mostly based on anecdotal evidence or studies performed in other species. It is not known how oral disease and the treatment (i.e. tooth extractions) can affect perioperative food intake, pain scores, additional analgesic requirements and behaviors in cats. Also, it is not known if a facial expression-based pain scale (Feline Grimace Scale: FGS) could be used for oral pain assessment as well. The objectives of this PhD program were: 1) to identify the specific behaviors associated with oral disease by using video assessment, and to verify their correlation with the real-time pain scores, 2) to assess the impact of oral disease and pain on food intake and feeding-related behaviors, 3) to determine the effects of oral disease treatment on behavior, pain scores and food intake, 4) to assess the inter-rater reliability of the FGS in cats undergoing dental extractions and 5) to evaluate the analgesic efficacy and adverse events of a high-concentration formulation of buprenorphine hydrochloride formulation (Simbadol, 1.8 mg/mL) in comparison with a standard buprenorphine hydrochloride formulation (Vetergesic, 0.3 mg/mL) as part of a multimodal regimen in cats undergoing dental extractions. The hypotheses were: 1) specific behaviors associated with oral disease would be identified and correlated with real-time pain scores, 2) cats with severe oral disease would have lower food intake and higher pain scores, and require rescue analgesia when compared with cats with no/minimal oral disease, 3) treatment of oral disease would reduce the prevalence of specific behaviors and pain scores and improve food consumption of these animals, 4) the FGS scores scored by different raters would be reliable in cats undergoing dental extractions and 5) both Simbadol and Vetergesic would produce similar postoperative pain scores, adverse events and timing and prevalence of rescue analgesia when using the Glasgow Composite Measure Pain Scale-Feline (CMPS-F). The project was divided into two studies and four articles (study 1: articles 1-3, study 2: article 4): 1) investigation of pain scores, rescue analgesia requirements and the amount of food intake in cats undergoing oral treatment, 2) investigation of the pain-induced specific behaviors related to oral pain in cats undergoing oral treatment, 3) investigation of inter-rater reliability of FGS in cats undergoing oral treatment, and 4) comparison of the analgesic efficacy of two dosage regimens using two different concentrations of buprenorphine in cats undergoing dental extractions. In article 1, twenty-four cats were equally divided into minimal (minimal dental treatment) or severe (multiple dental extractions) oral disease groups based on a dental scoring system which involved the number and location of teeth extraction and hospitalized for 7 days (admission on day 0, oral examination, radiographs and treatment under general anesthesia on day 1 and discharge on day 6). During hospitalization, pain scores based on CMPS-F, the prevalence of rescue analgesia (CMPS-F ≥ 5/20), dry and soft food intake (%) during periods of 3 minutes and 2 hours, daily soft food intake and serum inflammatory cytokines were analyzed and compared. In article 2, cats were filmed remotely for 10 min throughout the study at different time points (total of 36h of video recording). The videos consisted of four parts namely general, playing, feeding and post-feeding behaviors. The duration and frequency of different behaviors based on an ethogram were analyzed. In article 3, ninety-one image captures (i.e. screenshots) from videos filmed at days 1 (postoperative 6 hours) and 6 for article 2 and videos filmed before/after rescue analgesia were included. The FGS comprises five action units (AU): eyes, ears, muzzle, whiskers and head position. The FGS scores of the images were independently scored by four blinded raters. Inter-rater reliability of each AU and total FGS scores and the effect of the caregiver’s presence were evaluated. In study 2 (article 4), twenty-three cats undergoing tooth extractions were included. Cats randomly received either Simbadol (1.8 mg/mL; 0.24 mg/kg SC, every 24h, n = 11) or Vetergesic (0.3 mg/mL; 0.02 mg/kg IM, every 8h, n = 12) throughout the study. They were admitted on day 0, underwent oral examination, radiographs and treatment under general anesthesia on day 1 and discharged on day 4. Sedation and pain were scored using the dynamic interactive visual analog scale (day 1) and CMPS-F¬, respectively. Sedation and pain scores and the prevalence of rescue analgesia (CMPS-F ≥ 5/20) and resentment (defined as any type of escape behavior associated with aversion to drug administration) were analyzed. The studies found that the pain scores and the prevalence of rescue analgesia were significantly increased, and dry and soft food intakes were significantly decreased in cats with severe disease when compared with those with minimal disease, and the oral disease influences inflammatory cytokines and induces the specific behaviors. FGS is a reliable tool for the assessment of oral pain and is not affected by the caregiver’s presence. Pain scores and the prevalence of rescue analgesia in cats administered Simbadol were not significantly different from those administered Vetergesic, and some cats administered Vetergesic developed resentment to the administration of the drug, which was not significantly different from those administered Simbadol. Long-term analgesia is required after dental extractions in cats with severe oral disease. A decrease in food intake and specific behaviors identified in the studies could be used to differentiate painful versus pain-free cats in clinical practice. The FGS is a reliable tool for pain assessment in cats undergoing dental extractions. Simbadol produced similar analgesic effects to Vetergesic without resentment during drug administration

Consensus on circulatory shock and hemodynamic monitoring. Task force of the European Society of Intensive Care Medicine.

OBJECTIVE: Circulatory shock is a life-threatening syndrome resulting in multiorgan failure and a high mortality rate. The aim of this consensus is to provide support to the bedside clinician regarding the diagnosis, management and monitoring of shock. METHODS: The European Society of Intensive Care Medicine invited 12 experts to form a Task Force to update a previous consensus (Antonelli et al.: Intensive Care Med 33:575-590, 2007). The same five questions addressed in the earlier consensus were used as the outline for the literature search and review, with the aim of the Task Force to produce statements based on the available literature and evidence. These questions were: (1) What are the epidemiologic and pathophysiologic features of shock in the intensive care unit ? (2) Should we monitor preload and fluid responsiveness in shock ? (3) How and when should we monitor stroke volume or cardiac output in shock ? (4) What markers of the regional and microcirculation can be monitored, and how can cellular function be assessed in shock ? (5) What is the evidence for using hemodynamic monitoring to direct therapy in shock ? Four types of statements were used: definition, recommendation, best practice and statement of fact. RESULTS: Forty-four statements were made. The main new statements include: (1) statements on individualizing blood pressure targets; (2) statements on the assessment and prediction of fluid responsiveness; (3) statements on the use of echocardiography and hemodynamic monitoring. CONCLUSIONS: This consensus provides 44 statements that can be used at the bedside to diagnose, treat and monitor patients with shock

25th International Congress of the European Association for Endoscopic Surgery (EAES) Frankfurt, Germany, 14-17 June 2017 : Oral Presentations

Introduction: Ouyang has recently proposed hiatal surface area (HSA) calculation by multiplanar multislice computer tomography (MDCT) scan as a useful tool for planning treatment of hiatus defects with hiatal hernia (HH), with or without gastroesophageal reflux (MRGE). Preoperative upper endoscopy or barium swallow cannot predict the HSA and pillars conditions. Aim to asses the efficacy of MDCT’s calculation of HSA for planning the best approach for the hiatal defects treatment. Methods: We retrospectively analyzed 25 patients, candidates to laparoscopic antireflux surgery as primary surgery or hiatus repair concomitant with or after bariatric surgery. Patients were analyzed preoperatively and after one-year follow-up by MDCT scan measurement of esophageal hiatus surface. Five normal patients were enrolled as control group. The HSA’s intraoperative calculation was performed after complete dissection of the area considered a triangle. Postoperative CT-scan was done after 12 months or any time reflux symptoms appeared. Results: (1) Mean HSA in control patients with no HH, no MRGE was cm2 and similar in non-complicated patients with previous LSG and cruroplasty. (2) Mean HSA in patients candidates to cruroplasty was 7.40 cm2. (3) Mean HSA in patients candidates to redo cruroplasty for recurrence was 10.11 cm2. Discussion. MDCT scan offer the possibility to obtain an objective measurement of the HSA and the correlation with endoscopic findings and symptoms. The preoperative information allow to discuss with patients the proper technique when a HSA[5 cm2 is detected. During the follow-up a correlation between symptoms and failure of cruroplasty can be assessed. Conclusions: MDCT scan seems to be an effective non-invasive method to plan hiatal defect treatment and to check during the follow-up the potential recurrence. Future research should correlate in larger series imaging data with intraoperative findings

Dynamics of cerebral fluids in patients suffering from hydrocephalus and pseudotumour cerebri

This dissertation is devoted to dynamics of brain liquids in patients with altered CSF circulation and pressure-volume compensation. Since the introduction of intracranial pressure (ICP) monitoring, the studies of CSF dynamics have revealed unique information about the intracranial circulation and opened new opportunities for diagnosis and treatment of hydrocephalus and pseudotumour cerebri. The adaptation of infusion tests in clinical practice over 45 years ago has introduced a practical tool to benefit both patients and research into altered CSF dynamics. Objective testing of intracranial circulation in patients with clinical symptoms constitutes a unique situation, where the discovery of new patterns and reasons for disturbed intracranial circulation can be quantified. Such macroscopic yet practical quantifications can easily be translated to clinically useful information, and back, in real time or alternative past and future synchronicities. The aim of this dissertation is to demonstrate the value of testing CSF dynamics in vivo and how it could provide pathophysiological and clinical insights into hydrocephalus and pseudotumour cerebri syndrome (PTCS). My intention was to describe and reflect the main themes involved in the study of CSF dynamics: a) their role in diagnosis and treatment, b) their use in understanding shunts and shunt malfunction c) the need to optimise our understanding of the contents of ICP, meaning that long-term ICP monitoring or dynamic tests are required in CSF disorders, not snapshot ICP measurements and finally d) the mapping and quantification of the interaction between CSF circulation and cerebral blood flow (CBF). As the above foundations and results of my work lead to the formation of a required, albeit expected, long doctoral treatise, I have structured the later in 9 chapters containing a comprehensive literature review of the Resistance to CSF outflow as well as a systematic literature review of the CBF and autoregulation of the CBF in NPH. I have also dedicated a methods chapter, Chapter 3, into introducing and explaining the variable tested during a CSF infusion test, such as the fundamental amplitude of ICP and the compensatory reserve indices. Following this is the presentation of the data and clinical material used for my original projects. Specifically, my results contain the following: I) Autoregulation of cerebral blood flow in hydrocephalus CSF infusion tests provide a unique setting where both ICP and cerebral blood flow and autoregulation can be measured in ambulatory patients utilising many different methods. Autoregulation has been studied by quantifying the interaction between the CSF and cerebral blood circulation has revealed diagnostic and outcome implications that could perhaps describe the natural course of a CSF disorder, or differentiate between a CSF disorder and a vascular disorder, or the coexistence of the two, opening new chapters to the comprehension of shunt responsive NPH. I have explored the state of global autoregulation in patients undergoing infusion tests, in an attempt to set out a reference for investigations related to NPH, Resistance, autoregulation and their clinical implications. In the 5th chapter, I have: • Described the relationship between Rout, cerebral autoregulation and arterial blood pressure. Rout demonstrates a negative linear relationship with global autoregulation. When I combined these parameters and accounted for the patients’ age, I was able to show a good correlation with outcome, much improved compared to Rout alone. II) CSF dynamics in normal pressure hydrocephalus and pseudotumour cerebri. CSF dynamics in different conditions have shown that parameters such as the Resistance to CSF outflow in NPH and ICP at baseline combined with compensatory reserve indices in PTCS, could provide important diagnostic and management information. This could be a valuable addition of objective evidence to imaging and clinical examination. Using large cohorts of patients, I have explored the Resistance to CSF outflow (Rout) in NPH in the context of different aetiologies of NPH, its relationship with age as well as its overall correlation with outcome after shunting. I have also explored these relationships in relevance to clinical practice. In PTCS, I have described the findings from infusion tests in both adult and paediatric patients and have highlighted the differences with hydrocephalus. In chapter 6, , I have described the following: • Davson’s equation in NPH: The so-called Davson’s equation describes the relationship between ICP, Rout, CSF formation rate and sagittal sinus pressure under physiological circumstances. I have validated the existence of such a linear relationship in NPH. • CSF dynamics in post-traumatic hydrocephalus: Traumatic brain injury, as a cause of secondary NPH, shows some differences in Rout and ICP amplitude compared to idiopathic NPH. I have also described the effect of decompressive craniectomy and of cranioplasty on CSF dynamics. In chapter 7, I have explored the CSF dynamics of PTCS and in particular: • The coupling between CSF pressure and Sagittal sinus pressure (SSp) in PTCS patients at baseline and during infusion tests. I have also shown how this relates to Davson’s equation under an unstable SSp and the possible pathophysiological consequences of this finding. • The CSF dynamics of paediatric patients with PTCS. Those included all patients assessed in Cambridge and classified as definite, probable and not PTCS. III) Shunt testing in vivo. Shunts are currently the mainstay for the management of hydrocephalus, as well as an important part of the management of PTCS. They change CSF dynamic parameters in a way that is easily assessed with shunt infusion tests. The knowledge of the post-shunting CSF circulation contains crucial information on the state of the shunt function, as well as the adequate restoration of the patients’ intracranial circulation. I have described how objective knowledge from shunt testing in vivo impacts clinical practice and patients’ outcomes. In chapter 8, I have presented two studies about testing shunt function in-vivo: • Shunt testing in vivo using infusion tests is important in avoiding unnecessary revisions of patent shunts and allows patients to be managed conservatively, with good outcomes. This also translates to financial benefits for healthcare systems. • In paediatric hydrocephalus, shunt infusion studies are an accurate and useful tool for investigating insidious shunt obstruction. IV) Slow waves of Intracranial Pressure. Reliable, long-term overnight monitoring is the gold standard in monitoring and analysing ICP and its contents. Slow waves, compensatory reserve and relationship with the venous circulation contain reliable information that are again correlated to clinical practice and can be compared and incorporated into the shorter-term infusion test. I have explored the behaviour of slow waves in anaesthetized patients In chapter 9, I have investigated the influence of general anaesthesia on slow waves of ICP in NPH and traumatic brain injury (TBI) patients. Conclusion: Infusion tests are a practical tool for research and possibly diagnosis and treatment in patients with PTCS and NPH. CSF dynamics provide a quantitative description of cerebral pathophysiology in CSF disorders, both for CSF and potentially for cerebral blood flow. After shunting, infusion tests are a reliable and cost-effective tool for identifying or excluding shunt malfunction. Further studies are needed to verify the clinical implications of CSF infusion tests and cerebral blood flow and autoregulation in those patients

Echocardiography

The book "Echocardiography - In Specific Diseases" brings together contributions from well- known researchers from around the world, some of them specialized in imaging science in their clinical orientation, but also representatives from academic medical centers. Each chapter is structured and written to be accessible to those with a basic knowledge of echocardiography but also to be stimulating and informative to experts and researchers in the field of echocardiography. This book is primarily aimed at cardiology fellows during their basic echocardiography rotation, fellows of internal medicine, radiology and emergency medicine, but also experts in echocardiography. During the past few decades technological advancements in echocardiography have been developing rapidly, leading to improved echocardiographic imaging using new techniques. The authors of this book tried to explain the role of echocardiography in several special pathologies, which the readers may find in different chapters of the book