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Fluorinated hydrocarbons have transformed inhalational anaesthesia, and vaporizers are essential for safe and accurate delivery of these agents. The modern day vaporizers have evolved considerably since the ether inhaler invented by John Snow in 1847 and are robust, precise and efficient. For an anaesthetist to administer safe inhalational anaesthetic, it is important to understand the physical principles of the various inhalational anaesthetic agents along with the working principles of the vaporizers. Almost all modern vaporizers are located outside the circle system and the have multiple safety mechanisms in place.

Background and Objectives: End-stage renal disease (ESRD) is associated with increased anesthetic risks such as cardiovascular events resulting in higher perioperative mortality rates. This study investigated the perioperative and postoperative outcomes in ESRD patients receiving propofol target-controlled infusion with brachial plexus block during arteriovenous (AV) access surgery. Materials and Methods: We recruited fifty consecutive patients scheduled to receive AV access surgery. While all patients received general anesthesia combined with ultrasound-guided brachial plexus block, the patients were randomly assigned to one of two general anesthesia maintenance groups, with 23 receiving propofol target-controlled infusion (TCI) and 24 receiving sevoflurane inhalation. We measured perioperative mean arterial pressure (MAP), heart rate, and cardiac output and recorded postoperative pain status and adverse events in both groups. Results: ESRD patients receiving propofol TCI had significantly less reduction in blood pressure than those receiving sevoflurane inhalation (p < 0.05) during AV access surgery. Perioperative cardiac output and heart rate were similar in both groups. Both groups reported relatively low postoperative pain score and a low incidence of adverse events. Conclusions: Propofol TCI with brachial plexus block can be used as an effective anesthesia regimen for ESRD patients receiving AV access surgery. It can be used with less blood pressure fluctuation than inhalational anesthesia.

To investigate the agreement between the intraocular pressure (IOP) measurements in the awake condition and under different stages of general inhalational anesthesia using sevoflurane in both glaucomatous and normal children. A prospective study was performed on 43 glaucomatous children and 30 age-matched controls. Baseline IOP of one eye was measured immediately before general anesthesia using Perkins tonometer and then re-measured under light, intermediate, and deep anesthesia, and then after intubation. Depth of anesthesia was determined using bispectral index pediatric sensor. The agreement between the IOP measurements before and during different stages of anesthesia was analyzed using Bland–Altman plots. Systematic and proportionate deviations between the IOP measurements were analyzed. The mean age was 58.6 ± 41.99 months. The mean IOP was significantly lower at all stages of anesthesia in both groups. The coefficient of variation was over 20% in all measurements under anesthesia. For all IOP measurements during anesthesia, the limits of agreement were > 7 mmHg difference in the control group and > 20 mmHg in the glaucomatous group. The best agreement was with the IOP measurement after intubation (mean limit of agreement of -1.4 mmHg, 1.96 s range, −8.8–6 mm Hg) in the control group and with the IOP measurement under intermediate anesthesia (mean limit of agreement of −4.2 mmHg, 1.96 s range, −15.1–6.8 mm Hg) in the glaucomatous group. Inhalational anesthesia has variable effects on IOP measurement at all stages of anesthesia. Caution should be taken when extrapolating the true IOP from these measurements.

Background During inhalational induction of anaesthesia for children, severe respiratory events can occur but can be rapidly treated once intravenous access is in place. Reducing the time to successful cannulation during inhalational induction for children with poor vein visibility would improve safety. Objective To study the effectiveness of a near-infrared (NIR) vascular imaging device (Veinviewer) to facilitate intravenous cannulation. Design A prospective, multicentre, randomised, open clinical trial. Setting The operating rooms of three paediatric hospitals in Paris, France, from 1 October 2012 to 31 March 2016. Patients Children up to the age of 7 years, with poor vein visibility requiring general anaesthesia. Intervention Inhalational anaesthesia was initiated and intravenous cannulation was performed with the standard approach or with the Veinviewer Vision. Main outcome measures The primary outcome was the time to successful intravenous cannulation. A secondary outcome was the proportion of successful first attempts. Results The mean time to successful intravenous cannulation was 200 (95% CI, 143 to 295) seconds in the Veinviewer and 252 (95% CI, 194 to 328) seconds for the control group: hazard ratio 1.28 (1.02 to 1.60) (P = 0.03). The adjusted hazard ratio for known predictive factors was 1.25 (0.99 to 1.56) (P = 0.06). Success at the first attempt was 64.6% (102/158) in the 'Veinviewer' group vs. 55.6% (85/153) in the 'control' group (P = 0.10). Conclusion The Veinviewer has limited value in reducing the time to successful intravenous cannulation during inhalational anaesthesia for young children with poor vein visibility. However, there is a strong trend to reducing the delay in some cases and, given its absence of side effects, it could be part of a rescue option for a difficult venous-access strategy. Clinical trial registration NCT01685866 (http://www.clinicaltrials.gov).

Background Previous studies and meta analyses have led to incongruent and incomplete results respectively when total intravenous anesthesia (TIVA) and inhalational anesthesia (IA) are compared in endoscopic sinus surgeries in regards to intraoperative bleeding and visibility. Objective To perform a more comprehensive meta-analysis on randomized controlled trial (RCTs) comparing TIVA with IA in endoscopic sinus surgery to evaluate their effects on intraoperative bleeding and visibility. Methods A systematic review and meta-analysis of studies comparing TIVA and IA in endoscopic sinus surgery for chronic rhinosinusitis was completed in May 2020. Utilizing databases, articles were systematically screened for analysis and 19 studies met our inclusion criteria. The primary outcome included intraoperative visibility scores combining Boezaart, Wormald and Visual Analogue Scale (VAS). Secondary outcomes included rate of blood loss (mL/kg/min), estimated total blood loss (mL), Boezaart, Wormald scores, VAS, heart rate, and mean arterial pressure (MAP). Results 19 RCTs with 1,010 patients were analyzed. TIVA had a significantly lower intraoperative bleeding score indicating better endoscopic visibility (Boezaart, VAS, and Wormald) than IA (−0.514, p = 0.020). IA had a significantly higher average rate of blood loss than TIVA by 0.563 mL/kg/min (p = 0.016). Estimated total blood loss was significantly lower in TIVA than IA (−0.853 mL, p = 0.002). There were no significant differences between TIVA and IA in the mean heart rate (−0.225, p = 0.63) and MAP values (−0.126, p = 0.634). The subgroup analyses revealed no significant difference between TIVA and IA when remifentanil was not utilized and whenever desflurane was the IA agent. Conclusion TIVA seemed to have superior intraoperative visibility scores and blood loss during endoscopic sinus surgery when compared to IA. However, the results are not consistent when stratifying the results based on the use of remifentanil and different inhaled anesthetics. Therefore, the conclusion cannot be made that one approach is superior to the other.

Infographics are a new way of visually communicating information in a colorful and concise manner. They are becoming very popular in medical field since the last decade. Through infographics, one can understand the subjects through text, graphics, and images. Total intravenous anesthesia (TIVA) is a technique of general anesthesia (GA) given via intravenous (IV) route exclusively. In perspective of infographics, TIVA is far more understandable through its simple format. TIVA is also more advantageous than inhalational anesthesia. It avoids the deleterious effects of immunosuppressant and lacks any respiratory irritation, thus providing a good alternative anesthesia technique. Many peripheral surgeries can be done with the patient breathing spontaneously without any airway device, thus avoiding airway instrumentation, leading to droplet and aerosol generation. IV agents can be utilized to provide sedation during regional anesthesia (RA), which can easily be escalated to contain pain due to sparing of blocks or receding neuraxial anesthesia. The present narrative review focuses on the infographics in TIVA technique, providing highlights pertaining to its importance.

Objective: Analysis of the frequency and clinical manifestations of emergence agitation in children with background psycho‑ neurological disorders after general inhalational anesthesia during ophthalmic surgery.Methods: 1155 children aged 2–6 years having undergone different ophthalmic surgeries were examined. Children were conventionally divided into two groups: a main one (n=516) – children with different psychoneurological disorders; a comparison one (n=639) – children without psy‑ choneurological disorders. All patients got the general inhalational anesthesia with sevoflurane. The induction was performed intravenously with propofol.

Background Inhalational anesthesia and total intravenous anesthesia (TIVA) are techniques used for maintenance of general anesthesia for endoscopic sinus surgery (ESS). Growing evidence exists that TIVA may be associated with decreased bleeding and improved surgical fields, yet data suggest it is used in a minority of sinus surgery cases. The objective of this study was to investigate perceptions and approaches to anesthetic maintenance techniques in ESS among anesthesia providers. Methods A total of 719 anesthesiology residents, faculty, and certified registered nurse anesthetists (CRNAs) at 3 tertiary academic centers in the United States were invited to participate in a survey of considerations and practice patterns for inhalational anesthesia and TIVA for ESS. Results Responses were received from 200 participants (28%). Sixty-five percent of respondents reported a lack of familiarity with current literature on TIVA for ESS. Many considered factors other than surgical field visualization when choosing a maintenance technique. Most were comfortable with performing TIVA but stated they would participate in additional training. Conclusion The majority of anesthesiology providers were unaware of the existing literature demonstrating advantage in improved surgical visualization with TIVA. Many used a combination of inhaled and intravenous anesthetics for maintenance. These findings suggest that future opportunities may exist to develop education, training, and practice approaches specific to anesthetic techniques for ESS.

Background and Aims Hip fracture (HF) is common in emergency departments admission Mortality can reach 32% one year after surgery and delirium may affect 41% post-operative. Search for improved benefits from spinal (SP) or general anesthesia have shown inconsistent results. We aim to test if peripheral nerve blocks (PNB) with general inhalational anesthesia (GA), avoiding muscle relaxants and reducing opioids usage, may improve survival and delirium after HF repair when compared to spinal. Methods Hospital Ethics approval and patient informed consent were obtained. HF patients were randomized to Femoral and Lateral Cutaneous nerve block (PNB) with GA versus SP, for surgical repair (Hip prothesis, dynamic screw or femoral nail). Clinical data was collected throughout peri-operative period. CAM test was used to asses delirium and one year follow-up to assess survival. Descriptive statistics was used to characterize the sample and parametric and non-parametric tests were used to assess differences between groups. Results Groups demographics are in table 1. All ASA 4 patients were on the GA/PNB group, but the Man-Whitney test shows no difference in ASA distribution overall. Overall, 37% of patients had delirium up to 3 days after surgery and one year mortality was 19.3%.Table 2 shows the differences between PNB/GA and SP groups. Conclusions Overall survival and delirium rates are within the literature range. Although a trend to higher 1year mortality can be seen in the BNP/AG group, we did not find statistical differences in outcomes using peripheral nerve block/general inhalational anesthesia vs spinal. A larger study is needed to confirm these findings

Numerous studies have demonstrated the ability of isoflurane conditioning to provide multifaceted protection against aneurysmal subarachnoid hemorrhage (SAH)-associated delayed cerebral ischemia (DCI), however, preclinical studies have not yet examined whether other commonly used inhalational anesthetics in neurological patients such as sevoflurane or desflurane are also protective against SAH-induced neurovascular deficits. We therefore sought to identify the potential for sevoflurane and desflurane conditioning to protect against DCI in an endovascular perforation mouse model of SAH. Neurological function was assessed daily via neuroscore. Large artery vasospasm and microvessel thrombosis were assessed three days after SAH or sham surgery. Four groups were examined: Sham, SAH + room air, SAH + 2% Sevoflurane, and SAH + 6% Desflurane. For the SAH groups, one hour after surgery, mice received 2% sevoflurane, 6% desflurane, or room air for one hour. We found that conditioning with sevoflurane or desflurane attenuated large artery vasospasm, reduced microvessel thrombosis, and improved neurologic function. Given their frequent clinical use and strong safety profile in patients (including those with SAH), these data strongly support further studies to validate these findings in preclinical and clinical studies and to elucidate the mechanisms by which these agents might be acting.

Background: The search for methods for protection against delivery and labor pains has led to resumption of studies of non-invasive, safe and effective labor analgesia and inhalational anesthesia that could be used both separately and in combination with other methods. Recent research has demonstrated the highest efficacy of sevoflurane for analgesia of spontaneous delivery.Aim: To develop an optimized and effective method of inhalational analgesia with sevoflurane for spontaneous delivery.Materials and methods: We have performed a prospective study of the efficacy of inhalational sevoflurane for analgesia of spontaneous delivery. Thirty three obstetric patients were given sevoflurane-oxygen mixture according to a specially designed technique. The pain intensity was assessed with a visual analogous scale (VAS), sedation level, with Ramsay scale and Richmond Agitation-Sedation Scale (RASS).Results: The mean duration of inhalational anesthesia was 92.1±28 minutes [60–180']. There were no refusals and no switching to another type of analgesia. After induction of analgesia with Funding sevoflurane, there was a significant decrease of pain intensity by VAS by 34.9% from the baseline level (p = 0.00003); the pain was assessed as “moderate”. This trend was maintained throughout the whole exposure period.Conclusion: The results obtained confirm the possibility to use the proposed method of inhalational analgesia with sevoflurane to ensure effective analgesia in obstetric patients during delivery and labor.

Objective Achieving optimal intraoperative surgical field visibility and minimizing blood loss are two important parameters in endoscopic sinus surgery (ESS). The aim of this meta-analysis was to compare two total intravenous anesthesia (TIVA) and inhalational anesthesia (IA) to determine if either conferred superior outcomes of these and other parameters based on randomized control trials (RCTs) only. Methods The recommended Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines were followed, and searches of electronic databases from inception to September 2018 identified 157 articles for screening. Data were extracted and analyzed using meta-analysis of proportions. Results In total, we identified 15 RCTs that satisfied our selection criteria. There were 828 ESS cases described, with 391 (47%) and 437 (53%) being managed by TIVA and IA, respectively. Pooled analysis demonstrated significantly superior visibility scores for TIVA compared to IA based on 10-point grading scores (P = 0.049, visual analog scale; P = 0.009, Wormald scale) and 5-point grading scores (P = 0.002, Boezaart scale). Blood loss was significantly less following TIVA (P = 0.003), with no significant difference in intraoperative heart rate (P = 0.70) or mean arterial pressure (P = 0.96). Additionally, duration of surgery (P = 0.16) and anesthesia (P = 0.39) were comparable between the two approaches. Conclusion This meta-analysis indicates that TIVA has the potential to confer superior surgical field visibility and reduce intraoperative blood loss compared to IA in ESS. Currently, there are significant heterogeneity concerns in this meta-analysis, which temper any expectations that either approach is absolutely superior to the other. Caution should be exercised when interpreting these results until further validation can be achieved. Level of evidence 1A Laryngoscope, 130:575-583, 2020.

Lung gas exchange efficiency deteriorates during general anaesthesia due to ventilation–perfusion ( V/Q) scatter. Propofol total intravenous anaesthesia (TIVA) may preserve V/Q matching better than inhalational agents. We compared V/Q matching in patients randomized to either TIVA or sevoflurane anaesthesia, using deadspace and shunt measurements and the MIGET (Multiple Inert Gas Elimination Technique). Baseline arterial blood and mixed expired gas sampling was done before induction and repeated after one to two hours of relaxant general anaesthesia in 20 patients, supine with controlled ventilation at an FiO2of 0.3 and a target end-tidal PCO2of 30–35 mmHg. Blood samples for MIGET were processed after headspace equilibration by gas chromatography. The primary endpoint was a comparison of the two groups in the change from baseline of absolute difference between log standard deviation of ventilation and blood flow distributions (∂(σV−σQ)). Deadspace fraction increased and PaO2/FiO2ratio decreased across both groups overall with anaesthesia, but change in deadspace was not different between groups (mean (standard deviation, SD) sevoflurane 21.8% (11.7%) versus TIVA 20.5% (10.6%), P = 0.601). Change in PaO2/FiO2ratio was also similar between groups (mean (SD) sevoflurane −51.9 (69.1) mmHg versus TIVA −78.3 (76.9) mmHg, P = 0.43), as was change in shunt fraction (δQs/Qt mean (SD) sevoflurane −5.1% (12.6%) versus TIVA 0.4% (7.7%), P = 0.174). The primary endpoint ∂(σV−σQ) was not different between sevoflurane and propofol TIVA groups (mean (SD) 0.17 (0.81) versus 0.17 (0.29), P = 0.94). TIVA did not better preserve V/Q matching in patients undergoing anaesthesia with controlled ventilation compared with sevoflurane.

Reducing fresh gas flow during inhalational anaesthesia results in cost savings and decreases environmental impact. We are interested in the influence of fresh gas flow on the early (induction) phase of overall fresh gas flow and vapour consumption. This stage is often excluded in studies of fresh gas flow. Data were collected from 3199 sevoflurane anaesthetics over an 11-month period in four operating theatres. We determined fresh gas flow at different stages of anaesthesia, and developed an explanatory model for the influence of the 'induction' period. Following a three-month collection of baseline data we emphasised the importance of the early phase to our department repeatedly over a two-week period. We explored the relationship between fresh gas flow and total vapour usage, and used a simple mathematical model to explore the effect of changes in the fresh gas flow and duration of the 'induction' phase. Mean fresh gas flow was 1.15 l.min-1 in the baseline period and 0.91 l.min-1 in the two months following our educational effort (p = 0.0005). In the following six months, mean fresh gas flow was 1.17 l.min-1 (p = 0.7726 compared with baseline). These results were driven by changes in both fresh gas flow and duration of the initial high-flow period. We found some correlation (R2 = 0.85) between overall fresh gas flow and vapour consumption; a 1 l.min-1 increase in fresh gas flow consumes an additional 18 ml.hr-1 of liquid sevoflurane. This preliminary study demonstrates that an episode of high fresh gas flow at the start of anaesthesia has a large and modifiable effect on overall fresh gas flow and vapour consumption. We also confirmed the linear relationship between fresh gas flow and vapour usage.

INTRODUCTION: The effects of midazolam-based intravenous anesthesia (TIVA) and sevoflurane-based inhalation anesthesia (SEVO) maintenance on postoperative hematological parameters were compared in patients undergoing coronary artery surgery. METHODS: The 100 patients included in the study were divided into two groups according to the anesthesia management: All patients' anesthesia inductions were performed with 10 μgkg-1 fentanyl, 0.15 mgkg-1 midazolam, and 0.8 mgkg-1 rocuronium. Anesthesia was maintained with total intravenous anesthesia in the TIVA group patients, while sevoflurane was used in the SEVO group patients. Demographic, clinical, operative data, red cell distribution width (RDW), and mean platelet volume (MPV) values were recorded. RESULTS: Except that the extubation time was shorter in the SEVO group, no difference was observed between the groups in terms of all these variables. There was a significant increase in postoperative RDW and MPV measurements in both groups. Postoperative RDW value was lower in the inhalation anesthesia group compared to the TIVA group (p=0.013). DISCUSSION AND CONCLUSION: In our study, RDW was found to be lower in the inhalation anesthesia group, indicating less inflammation. There was no difference in terms of postoperative complications and mortality.

A multitude of factors in the perioperative period has an impact on short- and long-term outcomes after surgery. These factors are both unmodifiable patient-related risk factors and modifiable factors related to surgical approach and perioperative treatment protocols. There are apparently essential elements in the enhanced recovery after surgery (ERAS) approach that may have instrumental effects on long-term outcomes. Important aspects are the magnitude of adherence to ERAS, anesthetic modality, analgesic treatment, and magnitude of surgery. There is ample experimental evidence and limited clinical observational studies supporting this. However, the high-quality clinical evidence is lacking in general. Within the next few years, the results from major multi-institutional and multinational randomized clinical trials examining anesthetic modality will help us understand the importance of the intraoperative exposure of the oncological patient to different stressors, such as choice of intravenous or inhalational anesthesia. In general, there is need for more attention to the understanding of the individual risk factors for the patient scheduled for major surgery in order to tailor the right treatment protocol for the right patient at the right time by the right team.

We describe an unusual case of hyperacute hepatic failure following general anesthesia in a patient receiving a simultaneous kidney-pancreas transplant. Despite an aggressive evaluation of structural, immunological, viral, and toxicological causes, a definitive cause could not be elucidated. The patient required a liver transplant and suffered a protracted hospital course. We discuss the potential causes of fulminant hepatic failure and the perioperative anesthesia management of her subsequent liver transplantation. Resumo: Descrevemos um caso incomum de insuficiência hepática hiperaguda após a anestesia geral em uma paciente que recebeu um transplante simultâneo de rim-pâncreas. Apesar de uma avaliação agressiva das causas estruturais, imunológicas, virais e toxicológicas, uma causa definitiva não pôde ser identificada. A paciente precisou de um transplante de fígado que resultou em prolongamento da internação hospitalar. Discutimos as potenciais causas da insuficiência hepática fulminante e o manejo da anestesia no período perioperatório de seu subsequente transplante de fígado. Keywords: Liver failure, Kidney-pancreas transplant, Volatile agents, Liver transplant, Drug reaction, Isoflurane toxicity, Adverse drug reaction, Inhalational anesthesia, Palavras-chave: Insuficiência hepática, Transplante de rim-pâncreas, Agentes voláteis, Transplante de fígado, Reação medicamentosa, Toxicidade por isoflurano, Reação medicamentosa adversa, Anestesia inalatória

Resumo Descrevemos um caso incomum de insuficiencia hepatica hiperaguda apos a anestesia geral em uma paciente que recebeu um transplante simultâneo de rim‐pâncreas. Apesar de uma avaliacao agressiva das causas estruturais, imunologicas, virais e toxicologicas, uma causa definitiva nao pode ser identificada. A paciente precisou de um transplante de figado que resultou em prolongamento da internacao hospitalar. Discutimos as potenciais causas da insuficiencia hepatica fulminante e o manejo da anestesia no periodo perioperatorio de seu subsequente transplante de figado.

Background: The effects of intravenous and inhalation anesthesia on intraoperative and postoperative pulmonary inflammatory responses have been reported in many studies. The differences in clinical postoperative pulmonary complications (PPCs) have been also studied in cardiac and lung resection surgery. However, there are few relevant reports and the findings remain controversial. Clinical evidence for the effects of these two anesthetics on PPCs in other types of surgery is still missing. The main goal of the current study was to assess the impact of sevoflurane and propofol on the incidence of PPCs in patients undergoing oral and maxillofacial surgery. Methods: In this double-blind, randomized, controlled trial, we randomly assigned 220 adults at intermediate-to-high risk of pulmonary complications after oral and maxillofacial cancer surgery with radial forearm or fibular flap reconstruction to either propofol or sevoflurane as a general anesthetic. The occurrence of pulmonary complications according to the Clavien-Dindo score was defined as the primary (within 7 days after surgery) outcome. Results: The two intervention groups had similar characteristics at baseline. The PPCs incidence during 7 days after surgery was 32.4% and 18.2% in the propofol and sevoflurane groups, respectively (adjusted relative risk, 0.44; 95% confidence interval [CI], 0.22 to 0.91; P = 0.027). The corresponding incidence of PPCs in patients who underwent tracheotomy at the end of surgery in the two groups was 44.8% and 24.5% (adjusted relative risk, 0.39; 95% CI, 0.17 to 0.91; P = 0.030). In addition, the Clavien-Dindo classification showed significant differences between groups in minor complications (grade I and II) but not in major complications (grade III to V). Intergroup difference in the time to occurrence of the first PPC after surgery was significant (P = 0.021). There was no difference in postoperative hospital stay between the two groups. Conclusions: Compared with intravenous anesthesia, the administration of sevoflurane reduces the incidence of minor PPCs (grade I to II) in moderate- and high-risk patients who have undergone tracheotomy after oral and maxillofacial cancer surgery with radial forearm or fibular flap reconstruction.

OBJECTIVE To develop a technique for permanent sterilisation of female eastern grey kangaroos (Macropus giganteus) and red kangaroos (M. rufus) as part of a large-scale macropod management program on an enclosed 1545-ha site in western Sydney. METHODS Free-ranging female kangaroos (n = 1409: 1285 eastern grey kangaroos, 124 red kangaroos) were anaesthetised via remote anaesthetic drug delivery of tiletamine/zolazepam, medetomidine and acepromazine prior to inhalational anaesthesia using isoflurane-oxygen. A laparoscopic ovariectomy technique was developed using standard laparoscopic equipment to effect permanent sterilisation of the kangaroos. The technique described was also adapted for use on immature animals weighing as little as 1 kg. No direct post-surgical care was provided once the animals had recovered from the anaesthetic. RESULTS The procedure was simple to perform and had a very high success rate, with an overall project mortality rate of 2.13% (n = 30). Seven kangaroos (0.05% of all operated kangaroos) were euthanased as a direct result of the surgical procedure. Surgical complications were rare but included inadvertent gastrointestinal tract puncture with the trocar, intraoperative haemorrhage and subcutaneous emphysema leading to pouch eversion following surgery. CONCLUSION The procedure described is a rapid and effective method of permanent fertility control in macropods and carries a low mortality rate.

Background End-tidal target-controlled inhalational anaesthesia (TCIA) with halogenated agents (HA) provides a faster and more accurately titrated anaesthesia as compared to manually-controlled anaesthesia. This study aimed to measure the macro-economic cost-benefit ratio of TCIA as compared to manually-controlled anaesthesia. Methods This retrospective and descriptive study compared direct drug spending between two hospitals before 2011 and then after the replacement of three of six anaesthesia machines with TCIA mode machines in 2012 (Aisys carestation®, GE). The direct costs were obtained from the pharmacy department and the number and duration of the anaesthesia procedures from the computerized files of the hospital. Results The cost of halogenated agents was reduced in the hospital equipped with an Aisys carestation® by 13% as was the cost of one minute of anaesthesia by inhalation (€0.138 and €0.121/min between 2011 and 2012). The extra cost of the implementation of the 3 anaesthesia machines could be paid off with the resulting savings over 6 years. Discussion TCIA appears to have a favourable cost-benefit ratio. Despite a number of factors, which would tend to minimise the saving and increase costs, we still managed to observe a 13% savings. Shorter duration of surgery, type of induction as well as the way HA concentration is targeted may influence the savings results obtained.

An Ohio dentist, Corydon Munson, patented a gasometer with an attachment for vaporizing trace amounts of volatile general anesthetics or their mixtures into unoxygenated nitrous oxide. After vaporizing a variant of George Harley's ACE mixture into nitrous oxide, Munson branded his own novel anesthetic combination as ACENO.

Optical coherence tomography (OCT) is a fast, non-invasive, interferometric technique allowing high-resolution retinal imaging. It is an ideal tool for the investigation of processes of neurodegeneration, neuroprotection and neuro-repair involving the visual system, as these often correlate well with retinal changes. As a functional readout, visually evoked compensatory eye and head movements are commonly used in experimental models involving the visual function. Combining both techniques allows a quantitative in vivo investigation of structure and function, which can be used to investigate the pathological conditions or to evaluate the potential of novel therapeutics. A great benefit of the presented techniques is the possibility to perform longitudinal analyses allowing the investigation of dynamic processes, reducing variability and cuts down the number of animals needed for the experiments. The protocol described aims to provide a manual for acquisition and analysis of high quality retinal scans of mice and rats using a low cost customized holder with an option to deliver inhalational anesthesia. Additionally, the proposed guide is intended as an instructional manual for researchers using optokinetic response (OKR) analysis in rodents, which can be adapted to their specific needs and interests.

Inhaled anesthetics have been in clinical use for over 150 years and are still commonly used in daily practice. The initial view of inhaled anesthetics as indispensable for general anesthesia has evolved during the years and, currently, its general use has even been questioned. Beyond the traditional risks inherent to any drug in use, inhaled anesthetics are exceptionally strong greenhouse gases (GHG) and may pose considerable occupational risks. This emphasizes the importance of evaluating and considering its use in clinical practices. Despite the overwhelming scientific evidence of worsening climate changes, control measures are very slowly implemented. Therefore, it is the responsibility of all society sectors, including the health sector to maximally decrease GHG emissions where possible. Within the field of anesthesia, the potential to reduce GHG emissions can be briefly summarized as follows: Stop or avoid the use of nitrous oxide (N2O) and desflurane, consider the use of total intravenous or local-regional anesthesia, invest in the development of new technologies to minimize volatile anesthetics consumption, scavenging systems, and destruction of waste gas. The improved and sustained awareness of the medical community regarding the climate impact of inhaled anesthetics is mandatory to bring change in the current practice.

It is well known that low fresh gas flows result in lower cost of inhalational agents. A new generation of carbon dioxide absorbents allows low flow anesthesia with all anesthetics but these new compounds are more expensive. This study examines the cost of inhalational anesthesia at different fresh gas flows combined with the cost of absorbent. The cost of sevoflurane and desflurane is lower at low fresh gas flows. Paradoxically the cost of isoflurane is cheaper at 2 L/min than at lower fresh gas flows due to increased cost of carbon dioxide absorbent. Therefore low fresh gas flows should be used when feasible with sevoflurane and desflurane, but higher fresh gas flows up to 2 L/min may be more economical with isoflurane during maintenance phase of anesthesia.

Background: Rapid emergence with low soluble inhalational agents (IA) is offset by a significant association with emergence agitation (EA). Research on the influence of elimination methods of IA on recovery characteristics is very few. We conducted this study to compare the recovery characteristics of slow elimination (SE) of desflurane with purging technique. Methodology: Forty-five participants, 18–60 years, undergoing elective laparoscopic surgeries were randomised either into Group-P (n = 23) or Group-SE (n = 22). A standardised induction-maintenance protocol including desflurane and fresh gas flow (FGF) of 0.8 l/min was followed. During recovery, the FGF was increased in Group-P to 10 L/min and in Group-SE it was continued at 0.8 L/min. The decrement in end-tidal concentration of desflurane, time for emergence and extubation, EA and time for psychomotor recovery were noted. Results: Time for emergence (Group-SE: 22.8 ± 9 vs. Group-P: 5.6 ± 1.5 min; P = 0.000) and emergence to extubation duration (Group-SE: 128 ± 36 s vs. Group-P: 11.5 ± 1.7 s; P = 0.000) were longer in the Group-SE than in Group-P. EA occurred in 22.7% patients in Group-SE and in 4.3% patients in Group-P (P = 0.07). Psychomotor recovery to baseline values was seen in more number of patients in Group-SE than Group-P at 30 min. There was no difference between the groups at 60 min post-extubation. Conclusions: Slow elimination using FGF of 0.8 L/min significantly prolongs emergence even with low soluble agent like desflurane. SE is not beneficial in decreasing the incidence of EA or hastening psychomotor recovery. Purging technique is, therefore, a better-suited technique with fewer complications for eliminating desflurane.

Background and Aims: In contrast to propofol, volatile agents are often considered harmful to maintain anesthesia due to increasing brain volume and potential deleterious effects. Patients for cranioplasty, including patients with large bone defects, could be susceptible for intraoperative complications but have not properly been investigated so far. The aim of the present study was to evaluate brain swelling, intraoperative conditions, surgical course, and postoperative complication rates of propofol-based vs. volatile-based anesthesia. Material and Methods: In this monocentric, retrospective, and observational study, we collected demographic, clinical, and outcome data of patients undergoing cranioplasty between December 2010 and September 2014. According to the hypnotic drug used, patients were assigned to either a propofol or a volatile group. The primary outcome parameter was brain swelling. For comparison of the groups, univariate analysis was performed using Chi-square and Mann–Whitney-U test. Results: One hundred and one patients were identified in the period. Twenty-three patients were excluded due to cerebrospinal fluid diversion. Baseline characteristics and preoperative conditions did not vary between the groups except a higher body mass index and positive end-expiratory pressure (PEEP) in the propofol group. The choice of anesthesia (volatile or intravenous) influence neither the intraoperative local conditions nor postoperative complication rate. No significant risk factor for impaired bone flap placement was identified. Conclusions: In a well-defined cohort, the choice of the anesthetic agent does not influence the degree of intraoperative brain swelling, bone flap fit, and postoperative course.

To compare the effects on the brain metabolism of propofol-remifentanil total intravenous anesthesia and desflurane-remifentanil intravenous inhalational anesthesia in neurosurgery. Methods: Thirty-four neurosurgical patients with intracranial space-occupying surgery were randomly divided into two groups: Group A was conducted with the propofol-remifentanil total intravenous anesthesia and Group B with desflurane-remifentanil intravenous inhalational anesthesia. The patients were monitored for the brain metabolism prior to anesthesia, 1 hour after surgery, 2 hours after surgery, and half an hour after surgery. Results: The cerebral venous oxygen saturation, jugular bulb oxygen partial pressure, jugular vein oxygen content, and arterial oxygen content of the patients in group B were significantly higher than that of group A (P

Background Propofol and remifentanil intravenous combination is one popular form of total intravenous anesthesia (TIVA) in mainstream clinical practice, but it has rarely been applied to a rat model for laryngoscopy and laryngeal electromyography (LEMG). Our objective was to establish a safe and reproducible general anesthetic protocol for laryngoscopy and endoscopic LEMG in a rat model. Our hypothesis is that TIVA allows a minimally morbid, and feasible laryngoscopy and LEMG. Methods Sprague Dawley rats were subjected to either inhalational anesthesia (IA) (isoflurane) or TIVA (propofol and remifentanil) and underwent laryngoscopy and LEMG. The primary outcome was a complete minimally interrupted rigid laryngoscopy and obtaining reproducible motor unit potentials from the posterior cricoarytenoid muscles. The secondary outcome was morbidity and mortality. Results Seventeen out of twenty-two rats underwent both TIVA and IA. Only two underwent IA only. All nineteen rats that underwent IA had a successful experiment. Seventeen rats underwent TIVA, however, only nine completed a successful experiment due to difficulty achieving a surgical plane, and respiratory events. Upon comparing the success of the two anaesthetic regimens, IA was superior to TIVA (P = 0.0008). There was no statistical difference between the amplitudes (p = 0.1985) or motor units burst duration (p = 0.82605) of both methods. Three mortalities were encountered, one of which was due to lidocaine toxicity and two were during anesthetic induction. Respiratory related morbidity was encountered in two rats, all seen with TIVA. Conclusions TIVA is not an ideal anesthetic regimen for laryngeal endoscopy and LEMG in rat models. Contrary to our hypothesis, IA did not affect the quality of the LEMG and allowed a seamless rigid endoscopy. Electronic supplementary material The online version of this article (10.1186/s40463-018-0312-9) contains supplementary material, which is available to authorized users.

Aims: The aims of our study were (1) to compare success of probing done blindly and probing done under endoscopic assistance (2) to correlate the findings of blind probing with endoscopic examination findings. Materials and Methods: Retrospective comparative interventional case study. Total 98 eyes of 84 children were included in the study. The probing was performed under brief inhalational anaesthesia with a laryngeal mask. All probings, secondary and in children older than 24 months, were performed under endoscopic assistance only. Results: Total 111 probings were done out of which, ninety-eight (88.29%) were primary and 13 (11.71%) secondary. Seventy-six (68.4%) probings were done without and thirty-five(31.53%) probings were done with nasal endoscopic assistance. Out of 35, 22 (19.81%) probings were primary and 13 (11.71%) secondary. The mean age for probing was 18.2 +/12.5 months.Thirty eight (45.23%) were females and 46 (54.77%) were males. Out of 76 primary probings, 13 (17.10%) probings failed. The mean age of failed primary probing was 15.2 +/6.7 months. All 22 primary probings done under endoscopic guidance had successful outcome. Out of the total 111 probings, 2 (1.80%) probings failed who underwent endonasal dacryocystorhinostomy in the same sitting. Conclusion: Use of simultaneous nasal endoscopy during probing increases the success rate, minimizes secondary procedures and isof prognostic value for children with Congenital nasolacrimal duct obstruction (CNLDO).

It is important to understand the anesthetic requirements of elderly patients. However, little is known about age-related recovery from inhalational anesthetics. In this retrospective study, we compared age-related differences in recovery from three inhalational anesthetics in elderly subjects.Patients were investigated as three age groups which can be defined as age ranges pediatric ( 15 years), adult (15-64 years), and elderly patients ( 65 years) under general anesthesia using inhalational anesthetics. Anesthesia and surgery times, drug end-tidal concentrations, the time to first movement, time to eye opening, body movement, extubation, and discharge were recorded. The data were analyzed using a Kruskal-Wallis test and Steel-Dwass multiple comparisons.A total of 594 patients were included in the study. In inhalational anesthetics such as sevoflurane, isoflurane, or desflurane, recovery from general anesthesia was not significantly different among age groups (P 0.05). In inhalational group, recovery was significantly 5-40% faster in desflurane group than in other inhalational anesthetics groups (P 0.05). There were 20% faster recovery in pediatric and adult groups with desflurane than in elderly with desflurane group. Drug end-tidal inhalational concentrations in pediatric group were significantly higher than that in adult and elderly groups of all inhalational anesthetics, respectively (P 0.05).In the current study, we have found that recovery from desflurane was faster in younger patients than in other inhalational anesthetics and aged patients.

Total intravenous anesthesia (TIVA) has been used in veterinary medicine for decades, with developments and use being driven by similar indications to those in human medicine (such as neurosurgical procedures, respiratory compromise). Despite the wide range of cases that would benefit from the use of TIVA, it is mostly used in veterinary medicine when inhalation anesthesia is not possible due to circumstances, cost or location such as working in a third world country, performing humanitarian work, anesthetizing patients in remote locations (field, woods). Most general practice veterinarians prefer to use inhalational anaesthesia for ease and cost, while in academia, research or referee/specialised centres where specialised veterinary anesthetists and/or nurses are present, TIVA is more frequently used.