Anesthetic Events Research Articles

Post-anesthetic cortical blindness in cats: Twenty cases

The medical records of 20 cats with post-anesthetic cortical blindness were reviewed. Information collected included signalment and health status, reason for anesthesia, anesthetic protocols and adverse events, post-anesthetic visual and neurological abnormalities, clinical outcome, and risk factors. The vascular anatomy of the cat brain was reviewed by cadaver dissections. Thirteen cats were anaesthetised for dentistry, four for endoscopy, two for neutering procedures and one for urethral obstruction. A mouth gag was used in 16/20 cats. Three cats had had cardiac arrest, whereas in the remaining 17 cases, no specific cause of blindness was identified. Seventeen cats (85%) had neurological deficits in addition to blindness. Fourteen of 20 cats (70%) had documented recovery of vision, whereas four (20%) remained blind. Two cats (10%) were lost to follow up while still blind. Ten of 17 cats (59%) with neurological deficits had full recovery from neurological disease, two (12%) had mild persistent deficits and one (6%) was euthanased as it failed to recover. Four cats (23%) without documented resolution of neurological signs were lost to follow up. Mouth gags were identified as a potential risk factor for cerebral ischemia and blindness in cats.

Case Studies of Near Misses in Clinical Anesthesia

Case Studies of Near Misses in Clinical Anesthesia J. G. Brock-Utne Springer , July , 2011 , ISBN 978-1-4419-1178-0 , 236 pp., Price £35.99 Learning from adverse anaesthetic events, whether from books, journals, meetings or coffee-room conversations with colleagues, is an important method of improving the care we provide. Certain potentially disastrous events happen rarely; consequently they may not have been considered and a plan or solution may not be immediately to hand. Frequently, on hearing of a near miss, my initial relief that it didn’t happen to me is replaced by confidence that I’d be better prepared if it did. It is vital we learn from others’ mistakes and experiences, and this book offers a rich source of such material. With over 40 years’ clinical practice in Scandinavia, South Africa and the US, John Brock-Utne has collected 80 short case studies of near misses, all based on real cases. Though an eclectic mix, many are relevant to everyday anaesthetic practice: lost teeth; pulmonary aspiration; failure to flush intravenous lines; and difficulties inserting nasogastric tubes. All are events that have occurred in my workplace within the last few years. Through these 80 cases Brock-Utne has produced a scattershot of ‘top tips’ for anaesthesia. The typical format is a page detailing a scenario with enough information to diagnose and treat a possible anaesthetic catastrophe. Most start with a general statement, e.g.: “Today you are assigned to anesthetize a 52-year-old man with myasthenia gravis for a coiling of his cerebral aneurysm”. Others are more specific, my particular favourite being: “You are a retired anesthesiologist (72” and 250 lb) living in Maui, Hawaii”. There follows a question, and on the next page a solution is offered; finally a summary of the salient points is made in a recommendation. Each solution has a few references, many originating from the author’s department. Whilst most cases are set in the operating theatre, there is a diverse range. A breadth of anaesthetic practice is covered, from cardiac and neonatal surgery to minor day surgery. A small number of cases deal with intensive care, obstetric anaesthesia and the pre-operative assessment clinic. All but a few are set in developed world hospitals. Many of the cases deal with a single issue; a few concern interactions with other health care professionals, particularly surgeons, patients and their relatives. This is an underdeveloped aspect of the book; the place of non-clinical and human factors in near misses is touched on but could have been explored more fully. The cases are easy to read, although the text would have benefited from closer proof-reading. The lack of organisation is frustrating; it is often difficult to know the crux of a case from the title alone, there is no grouping of cases, and the index is poor. Furthermore the cases’ learning points are often underutilised. Only two cases have any figures, diagrams or data; too often we are simply told the interpretation of any investigations. The solutions offered are very pragmatic and whilst occasionally I did not fully agree with them or had an alternative, this does not detract from their usefulness. The solutions are often what was actually done, as opposed to an ideal answer; there is rarely one correct way to deal with a problem and the cases in this book can form the basis for discussion of alternative management plans. In summary, Brock-Utne is obviously a knowledgeable and passionate teacher and whatever the stage of your anaesthetic career you are bound pick up some previously unknown pearl of wisdom from this book. The book’s contents are concise, interesting and of practical use; however, accessing them should be easier.

Managing unforeseen events in anesthesia: collective trade-off between “understanding” and “doing”

This study aims to describe how anesthesia teams handle unforeseen events that may affect the patients' health. More precisely, it investigates the mechanisms of decisions made by anesthesia teams to manage unthought-of situations, i.e. situations that have not been foreseen as "possible" ones before their occurrence. An empirical study, based on the analysis of simulated situations, was conducted in a pediatric anesthesia service of a university hospital in France. The results highlighted three ways of managing unthought-of situations (determined management, cautious management and overwhelmed management). They support the hypothesis of a collective cognitive trade-off, whereby teams would behave as virtual operators, with their own collective trade-off between "understanding" and "doing". The discussion of the results questions the assessment criteria, the safety perspectives we adopt and the possible ways to improve the management of unforeseen situations.

How do you use bispectral index effectively for preventing re-awareness during general anesthesia?

Low incidence (0.1-0.4%) [1,2] awareness during intended general anesthesia brings significant postoperative sequelae to the patient, including sleep disturbances, nightmares, daytime anxiety, and even late psychological symptoms [3]. Traditionally, the detection of intraoperative awareness has been conducted by observing patient movement or developments of tachycardia and hypertension. However, these approaches are often hindered by anesthetics and supportive medicines used during general anesthesia and various surgical events. Recently, the Bispectral index (BIS), a mathematically derived electroencephalographic (EEG) derivative [4], has been adopted during general anesthesia to monitor anesthetic depth. By maintaining the BIS between 40 and 60, which is the manufacturer's recommended value for general anesthesia, a reduction of anesthetic requirement and shorter length of stay in PACU can be achieved [5]. However, a large-scale prospective study (n = 967) reveals that the incidence rate for anesthesia awareness is 0.62% of BIS protocol based monitoring during general anesthesia [6]. Therefore, we need to consider which method is desirable to prevent re-awareness during general anesthesia using BIS monitoring. Seol et al. [7], in this issue of the Korean Journal of Anesthesiology, suggests the role of BIS for monitoring intraoperative awareness, although this is not the main theme of the article. In this present study, when the patients were forced back to awareness during general anesthesia with sevoflurane or desflurane, the mean BIS value at the first response to verbal command was about 90. If the BIS value corresponding to the response to verbal command during anesthetic induction closely parallels that at the time of re-awareness during anesthesia, we can use the BIS values of anesthetic induction for monitoring anesthetic awareness. In the study using propofol, the BIS value was between 51 and 85 (median 67) at the point of transition to re-awareness from loss of response to verbal command [8]. In addition, in the course of induction by propofol, the range of BIS when maintaining the response to verbal command was similar to that of re-awareness from loss of consciousness: between 57 and 88 (median about 80) [9]. However, the median BIS value seemed to be higher during re-awareness than during induction. Further research is necessary to determine if the BIS value in the course of induction is an available parameter to detect re-awareness during surgery under general anesthesia. Furthermore, to use BIS effectively, we should also consider the degree of muscle paralysis. It is known that the BIS value reflects not only electroencephalographic (EEG) activity but also electromyographic (EMG) activity of the facial muscles [10]. After administering muscle relaxants without any sedatives, the BIS value dropped to between 9 and 64, accompanied by the decline of EMG activity. Also, these variations of the BIS decline might be dependent on the degree of neuromuscular blockade. In the study by Seol et al. [7], a wake-up test was not conducted until confirming neuromuscular full recovery by a nerve stimulator. For this reason, BIS related to awareness might record a high value at about 90. Paradoxically, the published reports of awareness have increased since 1990, even though there have been remarkable advancements in the field of anesthesiology [3]. Based on the complaints of the patients with unwanted awareness, the universal use of muscle relaxants during surgical procedures may be closely associated with the increasing incidence of awareness. Also, episodes of awareness have been reported most frequently during anesthetic maintenance, when the neuromuscular block is usually sustained for a suitable surgical condition. Muscle paralytic degrees are changeable during maintenance in each patient because of the variable pharmacokinetic and pharmacodynamic characters of muscle relaxants. Therefore, the variable influences of the current EMG component on the BIS value should be considered when interpreting the values. If a neuromuscular block is conducted, the recommended BIS value would not fully guarantee complete hypnosis. According to the article by Avidan et al. [6], anesthesia awareness was reported at an incidence rate of 0.31% when the minimum alveolar concentration (MAC) value of the anesthetics used was maintained between 0.7-1.3. This data was lower than that of the BIS monitoring based anesthesia, although there was no statistical significance. Therefore, in the cases of using muscle relaxants, BIS monitoring along with MAC based anesthetic management might be desirable. In conclusion, considerable care is necessary in the interpretation of the BIS value when muscle relaxants are administered. Henceforth, it may be necessary to investigate the validity of using the BIS value during the induction period for detecting intraoperative re-awareness.

Anesthetic induction with guaifenesin and propofol in adult horses

To evaluate whether guaifenesin can prevent adverse anesthetic induction events caused by propofol and whether a guaifenesin-propofol induction combination has brief cardiovascular effects commensurate with rapid drug washout. 8 healthy adult horses. Guaifenesin was administered IV for 3 minutes followed by IV injection of a bolus of propofol (2 mg/kg). Additional propofol was administered if purposeful movement was detected. Anesthesia was maintained for 2 hours with isoflurane or sevoflurane at 1.2 times the minimum alveolar concentration with controlled normocapnic ventilation. Normotension was maintained via a dobutamine infusion. Plasma concentrations of propofol and guaifenesin were measured every 30 minutes. Mean ± SD guaifenesin and propofol doses inducing anesthesia in half of the horses were 73 ± 18 mg/kg and 2.2 ± 0.3 mg/kg, respectively. No adverse anesthetic induction events were observed. By 70 minutes, there was no significant temporal change in the dobutamine infusion rate required to maintain normotension for horses anesthetized with isoflurane or sevoflurane. Mean plasma guaifenesin concentrations were 122 ± 30 μM, 101 ± 33 μM, 93 ± 28 μM, and 80 ± 24 μM at 30, 60, 90, and 120 minutes after anesthetic induction, respectively. All plasma propofol concentrations were below the limit of quantitation. Guaifenesin prevented adverse anesthetic induction events caused by propofol. Guaifenesin (90 mg/kg) followed by propofol (3 mg/kg) should be sufficient to immobilize > 99% of calm healthy adult horses. Anesthetic drug washout was rapid, and there was no change in inotrope requirements after anesthesia for 70 minutes.

Use of Ephedrine for the Short-Term Treatment of Postoperative Nausea and Vomiting: A Case Report

Ephedrine, a well-known sympathomimetic agent, is used in the perioperative setting to treat acute hypotension, especially hypotension related to anesthetic events. Ephedrine's unlabeled use as an antiemetic agent is less well known despite its efficacy and safety profile for short-term and/or prophylactic treatment. The following case report describes the benefits of using ephedrine to mitigate postoperative nausea and vomiting and associated dizziness while waiting for longer lasting therapy to take effect and/or use as a secondary agent.

Alfaxalone anaesthesia in the green iguana (Iguana iguana)

ObjectiveTo characterise the anaesthetic effects of alfaxalone administered intramuscularly (IM) at 10, 20, and 30 mg kg−1. Study designProspective, randomized cross-over study. AnimalsTen juvenile green iguanas (Iguana iguana) of mean body weight (±SD) 480 ± 134 g. MethodsAlfaxalone was administered IM in the triceps of both thoracic limbs. Times for anaesthetic induction, plateau and recovery periods were recorded. Skeletal muscle tone of the jaw, neck, thoracic limbs, pelvic limbs, and tail was scored. The palpebral, corneal and righting reflexes, and the response to painful stimuli were also assessed. Pulse rate and respiratory rate were recorded. Comparisons between different dosages and over time were made using anova. ResultsTimes are given for 10, 20 and 30 mg kg−1 dosages respectively: mean time to maximal effect was 7.7 ± 2.2, 5.4 ± 1.7 and 3.9 ± 1.2 minutes; duration of the plateau phase was 11.3 ± 3.8, 22.1 ± 6.5 and 39.1 ± 11.5 minutes; recovery time was 10 ± 2.4, 17.5 ± 8.6 and 25 ± 7.1 minutes; and total anaesthetic duration was 29 ± 35.7, 45 ± 8.2 and 68 ± 9.8 minutes. Endotracheal intubation was possible in 40% of the subjects given 10 mg kg−1 and in 100% subjects given both 20 and 30 mg kg−1. Loss of response to a painful stimulus was seen in 0/10, 8/10 and 9/10 animals at 10, 20, and 30 mg kg−1 respectively. There was an initial dose-dependent depression of respiration followed by a significant increase in frequency over time. In contrast, pulse rates decreased by 20% over the duration of the anaesthetic events. Conclusions and clinical relevanceIntramuscular administration of alfaxalone is a simple, rapid and reliable means of achieving relatively brief sedation or anaesthesia in healthy green iguanas. A dosage of 10 mg kg−1 provides light sedation, appropriate for examination and venipuncture; 20 mg kg−1 provides a level suitable for minor procedures or for endotracheal intubation and supplementation with inhalational anaesthesia; 30 mg kg−1 produces an anaesthetic plane suitable for surgical procedures of limited duration (up to 40 minutes).

Clinical factors associated with the non-utilization of an anaesthesia incident reporting system

Incident reporting is a widely recommended method to measure undesirable events in anaesthesia. Under-utilization is a major weakness of voluntary incident reporting systems. Little is known about factors influencing reporting practices, particularly the clinical environment, anaesthesia team composition, severity of the incident, and perceived risk of litigation. The purpose of this study was to assess each of these, using an existing anaesthesia database. We performed a retrospective cohort study and analysed 46 207 surgical patients. We used multivariate analysis to identify factors associated with the non-utilization of the reporting system. We found that in 7022 (15.1%) of the procedures performed, the incident reporting system was not used. Factors associated with the non-use of the system were regional anaesthesia/local anaesthesia, odds ratio (OR) 1.64 [95% confidence interval (CI) 1.03-2.62], emergency procedures OR 1.15 (95% CI: 1.05-1.27), and a consultant anaesthetist working without a trainee, OR 1.71 (95% CI: 1.03-2.82). In contrast, factors such as longer duration of surgery, OR 0.85 (95% CI: 0.76-0.94), the presence of a senior anaesthesia trainee, OR 0.86 (95% CI: 0.81-0.92), and the occurrence of severe complications with a high risk of litigation (i.e. death, nerve injuries) were less associated with a non-use of the reporting system, OR 0.65 (95% CI: 0.44-0.97). Team composition and time of day had no measurable impact on reporting practices. Clinical factors play a significant role in the utilization of an anaesthesia incident reporting system and more particularly, severity of complications and higher liability risks which appear more as incentives than barriers to incident reporting.

Cardiac arrest upon induction of anesthesia in children with cardiomyopathy: an analysis of incidence and risk factors

It is thought that patients with cardiomyopathy have an increased risk of cardiac arrest on induction of anesthesia, but there is little available data. The purpose of this study was to identify the incidence and potential risk factors for cardiac arrest upon induction of anesthesia in children with cardiomyopathy in our institution. A retrospective chart review was performed. Eligible patients included patients admitted between 1998 and 2008 with the International Statistical Classification of Disease code for cardiomyopathy (ICD-9 code 425) who underwent airway intervention for sedation or general anesthesia in the operating room, cardiac diagnostic and interventional unit (CDIU) or intensive care unit. Patients undergoing emergency airway intervention following cardiovascular collapse were excluded. For each patient, we recorded patient demographics, disease severity, anesthesia location, and anesthetic technique. One hundred and twenty-nine patients with cardiomyopathy underwent a total of 236 anesthetic events, and four cardiac arrests were identified. One was related to bradycardia (HR<60), two were attributed to bradycardia in association with severe hypotension (systolic blood pressure<45), and the fourth arrest was related to isolated severe hypotension. Two occurred in the operating suite and two in the CDIU. There was no resulting mortality. One patient progressed to heart transplantation. Multiple combinations of anesthetic drugs were used for induction of anesthesia. We performed a review of the last 10 years of anesthesia events in children with cardiomyopathy. We report four cardiac arrests in two patients and 236 anesthetic events (1.7%). To the best of our knowledge, this is the largest review of these patients to date but is limited by its retrospective nature. The low cardiac arrest incidence prevents the identification of risk factors and the development of a cardiac arrest risk predictive clinical tool.

Intraperitoneal Local Anesthetic Improves Recovery After Colon Resection

Two wounds are created after abdominal surgery. The surgical insult to the peritoneal cavity and viscera has not been emphasized as a target for interventions. In animal models vagotomy blunts the intraperitoneal response to induced inflammation. This is not feasible in humans. However a transient chemical afferentectomy after colectomy by using neuraxial blockade (epidural) and intraperitoneal blockade may be possible. We investigated the effects of intraoperative instillation and postoperative infusion of intraperitoneal local anesthetic (IPLA) on recovery parameters after colectomy, in the setting of an established enhanced recovery after surgery (ERAS) program. Double blinded, randomized, placebo controlled design. The study group (IPLA) received instillation of intraperitoneal ropivacaine (75 mg) before dissection and postoperative infusion of 0.2% solution at 4 mL/hour for 3 days continuously. The placebo group (NS) was treated as above with 0.9% saline solution. All patients were cared for under ERAS standardized perioperative care. Epidural infusion was stopped on day 2. Patients were discharged from day 3 onwards once criteria met. Perioperative data, surgical recovery score (SRS), complications, and length of stay were recorded. Systemic cytokines response, neuroendocrine parameters, pain measures and opioid use data were collected. Patients were followed up for 60 days. Sixty patients were recruited. Patients were equivalently matched at baseline. There were no local anesthetic related adverse events. The complication rate, including anastomotic leak rate, was equivalent between groups. IPLA group had better SRS scores for the duration of intraperitoneal infusion. Pain and opioid use was reduced in the IPLA group. Systemic cytokine and cortisol response was diminished in the IPLA group. IPLA group had consistently higher systemic ropivacaine levels than placebo group. Instillation and infusion of intraperitoneal ropivacaine after colectomy improves early surgical recovery. This was associated with a blunting of postsurgical systemic cytokines and cortisol. Patients also had significantly reduced pain and opioid use over and above the effect of an epidural infusion. Therefore a transient chemical afferentectomy with clinical benefit is possible with this method. A longer IPLA infusion duration needs to be studied. This study is registered at clinicaltrials.gov and carries the ID number NCT00722709.

Abomasal Impaction in Captive Bongo (Tragelaphus eurycerus)

Fatal abomasal impaction, often combined with omasal impaction, was diagnosed in 11 bongo (Tragelaphus eurycerus) from five different zoologic collections in the United States between 1981 and 2009. Nine of 11 cases occurred in young females (10 mo-7 yr old) and typical clinical signs prior to diagnosis or death included partial or complete anorexia, dehydration, and scant fecal production. Although the clinical histories in several of the earlier cases are incomplete, clinical signs were known to begin shortly after an anesthetic event in five of 11 bongo (45%). Pedigree analysis indicates that affected bongo were descendants of multiple founders and not from a single family line, suggesting that the development of abomasal impaction is not a strictly inheritable trait. Treatment, when attempted, was variable and included abomasotomy and removal of impacted ingesta, drug therapy (prokinetic drugs, nonsteroidal anti-inflammatories, antimicrobials), fluid therapy, and administration of oral lubricants or intralesional stool softeners. Based on the outcomes in the cases presented here, the prognosis for bongo with abomasal impaction is considered poor to grave.

Malignant Disease Within 5 Years After Surgery in Relation to Duration of Sevoflurane Anesthesia and Time with Bispectral Index Under 45

Surgery, general anesthesia, and related events have been implicated to promote cancer proliferation. We investigated the incidence of cancer within 5 years after surgery in relation to duration of anesthesia (T(ANESTH)) and also by time with bispectral index (BIS) under 45 (T(BIS<45)) serving as a proxy for more profound anesthesia exposure. New malignant diagnoses after surgery under sevoflurane anesthesia were obtained in a prospective cohort of 2972 BIS-monitored patients without any clinically diagnosed malignant disease at the time of index surgery. The risk of cancer during follow-up in relation to T(ANESTH) and T(BIS<45) was assessed by Cox regression. The cancer incidence in this surgical population was compared with the incidence in a standardized general population by calculation of standard incidence ratio. One hundred twenty-nine patients (4.3%) were assigned 136 new malignant diagnoses within 5 years after surgery. No relation between T(ANESTH) or T(BIS<45) and new malignant disease was found, nor were any significant relations obtained when other thresholds for BIS (i.e., <30, <40, and <50, respectively) were used in the calculations. The standard incidence ratio for new malignant disease was 1.37 (confidence interval, 1.15-1.62). Neither duration of anesthesia nor increased cumulative time with profound sevoflurane anesthesia was associated with an increased risk for new malignant disease within 5 years after surgery in previously cancer-free patients.

Major complications of airway management in the UK: results of the Fourth National Audit Project of the Royal College of Anaesthetists and the Difficult Airway Society. Part 1: Anaesthesia

This project was devised to estimate the incidence of major complications of airway management during anaesthesia in the UK and to study these events. Reports of major airway management complications during anaesthesia (death, brain damage, emergency surgical airway, unanticipated intensive care unit admission) were collected from all National Health Service hospitals for 1 yr. An expert panel assessed inclusion criteria, outcome, and airway management. A matched concurrent census estimated a denominator of 2.9 million general anaesthetics annually. Of 184 reports meeting inclusion criteria, 133 related to general anaesthesia: 46 events per million general anaesthetics [95% confidence interval (CI) 38-54] or one per 22,000 (95% CI 1 per 26-18,000). Anaesthesia events led to 16 deaths and three episodes of persistent brain damage: a mortality rate of 5.6 per million general anaesthetics (95% CI 2.8-8.3): one per 180,000 (95% CI 1 per 352-120,000). These estimates assume that all such cases were captured. Rates of death and brain damage for different airway devices (facemask, supraglottic airway, tracheal tube) varied little. Airway management was considered good in 19% of assessable anaesthesia cases. Elements of care were judged poor in three-quarters: in only three deaths was airway management considered exclusively good. Although these data suggest the incidence of death and brain damage from airway management during general anaesthesia is low, statistical analysis of the distribution of reports suggests as few as 25% of relevant incidents may have been reported. It therefore provides an indication of the lower limit for incidence of such complications. The review of airway management indicates that in a majority of cases, there is 'room for improvement'.

Printed anesthetic-risk information and perioperative anxiety: a multi-center study

Abstract Background: Currently, there is a considerable variation concerning the provision of preanesthetic-risk information, especially potential detrimental adverse outcomes. Objective: Determine the effects of printed anesthetic-risk information before surgery including patients’ anxiety, refusal of surgery, knowledge perception of adverse events and factors affecting anxiety. Methods: Patients in a university hospital, a tertiary care hospital, a secondary care hospital, and a neurological institute in Thailand, undergoing low-to-moderate risk surgery were randomly allocated to control group (C) and study group (S), where group C received printed general information in anesthesia, and group S received printed incidences of five anesthetic adverse events as sore throat, nausea/vomiting, tooth loss, not waking up after surgery, cardiac arrest. Spielberger State-Trait Anxiety Inventory Scale (STAIS, STAIT) for anxiety and Visual Analog Scale (VAS) for knowledge perception were recorded before and after information, and after surgery. Numbers of patients who refused surgery and needed anesthetic-risk information in the next surgery were also recorded. STAIS &gt;45 were considered “high anxiety”. Results: Eight-hundred and twenty-four patients were analyzed (group C: 414, group S: 410). There was no difference in age, sex, ASA physical status, salary, education level, habitat, anesthetic experience and operative risk between groups. STAIS and STAIT, proportion of patients with high anxiety, proportion of patients who refused surgery were not different between groups. Patients in control group needed anesthetic-risk information in the next surgery more than study group (p &lt;0.001). VAS for knowledge about five adverse events in study group were significantly higher than control group (p &lt;0.001). Risk factors by the multivariate analysis included patients with high baseline trait anxiety and low income of less than 10,000 Baht/month. Conclusion: Printed anesthetic-risk information did not increase anxiety, but increased knowledge perception of the patients.

A rude awakening after our fourth ‘NAP’: lessons for airway management

A rude awakening after our fourth ‘NAP’: lessons for airway management

Atlas of Ultrasound-Guided Regional Anesthesia.

University of Utah, Salt Lake City. jennifer.davis@hsc.utah.eduBy Andrew T. Gray, M.D., Ph.D. Philadelphia, Saunders Elsevier, 2010. Pages: 365. Price: $165.00.For those of us who perform regional anesthesia, ultrasound technology has revolutionized our practice in many ways. As the literature supporting the use of ultrasound guidance in regional anesthesia continues to mount, it has been a daunting task for practitioners who trained before this technology was in use to incorporate it into their practice. Atlas of Ultrasound-Guided Regional Anesthesia is a unique and extremely informative resource for practitioners who are attempting to learn ultrasound-guided regional anesthesia as well as experienced regionalists who want to expand their block armamentarium.The Atlas consists of 62 concise chapters and two appendices of self-assessment questions and answers. Each chapter, which is up to 11 pages long, begins with a detailed description of the topic, followed by suggested techniques where applicable, clinical pearls, and extensive pictures.The first 15 chapters of the book discuss the fundamental principles of ultrasound and its terminology. The author discusses various imaging techniques, transducer manipulation, and needle approaches. During many of the workshops I teach, participants express their frustration at not being able to “get a good image” when no one with experience is around to guide them. These pages clearly and concisely explain the ultrasound concepts that are essential to becoming a skilled ultrasonographer and safely performing ultrasound-guided blocks.The book's second section describes the ultrasound appearance of comingled structures, such as tendons, blood vessels, lymph nodes, pleura, and bone. The remainder of the book addresses ultrasound-guided techniques for upper extremity blocks, lower extremity blocks, trunk blocks, and head and neck blocks in a great deal of breadth but without too much depth on any given procedure. The final section is devoted to adverse events in regional anesthesia and using ultrasound for both prevention and recognition thereof. It is noteworthy that this book has the benefit of being available online so practitioners have ready access to the text and numerous pictures.The Atlas is a valuable addition to our literature on ultrasound-guided regional anesthesia. Before the publication of this book, there were very few texts of this nature available to practitioners who are attempting to introduce ultrasound to their practice. The descriptions of ultrasound fundamentals are well written and well illustrated. The pictures in the book are plentiful, of outstanding quality, and clearly labeled—an essential feature for learning ultrasound-guided regional anesthesia.The author gives helpful suggestions for block techniques. However, I would caution the reader to remember that many of the techniques described in this book represent regional preferences. With an adequate understanding of anatomy, there are a number of acceptable techniques for each block. A nice addition to this book would have been online video clips for each block, with transducer position as a correlate. Such a feature would allow demonstration of ultrasound principles and transducer manipulation, with corresponding changes in image appearance. Although still images are important, video clips add a great deal to a reader's understanding of block performance.Overall, this book is extremely useful and well done. The Atlas is a much-needed addition to our literature and will be a valuable resource for practitioners who are learning ultrasound-guided regional anesthesia.University of Utah, Salt Lake City. jennifer.davis@hsc.utah.edu

Smart Alerts: Development of Software to Optimize Data Monitoring

Monitoring is useful for vital follow-ups and prevention, diagnosis, and treatment of several events in anesthesia. Although alarms can be useful in monitoring they can cause dangerous user's desensitization. The objective of this study was to describe the development of specific software to integrate intraoperative monitoring parameters generating "smart alerts" that can help decision making, besides indicating possible diagnosis and treatment. A system that allowed flexibility in the definition of alerts, combining individual alarms of the parameters monitored to generate a more elaborated alert system was designed. After investigating a set of smart alerts, considered relevant in the surgical environment, a prototype was designed and evaluated, and additional suggestions were implemented in the final product. To verify the occurrence of smart alerts, the system underwent testing with data previously obtained during intraoperative monitoring of 64 patients. The system allows continuous analysis of monitored parameters, verifying the occurrence of smart alerts defined in the user interface. With this system a potential 92% reduction in alarms was observed. We observed that in most situations that did not generate alerts individual alarms did not represent risk to the patient. Implementation of software can allow integration of the data monitored and generate information, such as possible diagnosis or interventions. An expressive potential reduction in the amount of alarms during surgery was observed. Information displayed by the system can be oftentimes more useful than analysis of isolated parameters.

Anaesthesia and unexpected phaeochromocytoma

An unexpected phaeochromocytoma represents one of the most serious events in anaesthesia, and unless well managed, carries a very high mortality. Although the problem is not common, anaesthetists may be faced with an unexpected phaeochromocytoma either in intensive care, or as a complication of almost any surgical procedure. Phaeochromocytoma is frequently undiagnosed as it may present with a bewildering array of symptomatology (Table I) and patients may be normotensive or even hypotensive, depending on the nature and expression of the tumour. Preoperative absence of symptoms does not exclude the diagnosis. Patients may also present with a variety of medical emergencies. The most hazardous presentation is that of phaeochromocytoma multisystem crisis which carries a very high mortality.

Who needs an IV? Retrospective service analysis in a tertiary pediatric hospital

The question if it is possible and safe to anesthetize children for short procedures without intravenous (IV) access provokes strong opinions among pediatric anesthetists. However, only limited data are available to support either side of the arguments. This pediatric university hospital provides anesthesia to a community dental service, led by staff anesthesiologists. A rapid turnover system based on inhalational induction and maintenance of anesthesia without mandatory IV access has been employed since 2005. A retrospective service analysis was performed to identify the incidence of adverse anesthesia events. A total of 6440 children with an average (± SD) age of 8.1 (± 4.1) years and weight of 29.6 (± 13.5) kg were cared for over the 5-year period. The total number of children refusing to undergo inhalational induction was 81 (1.26%) and 19 (0.3%) elected for an IV induction. One-third received cannulation for delivery of IV analgesia. There were no adverse anesthesia events requiring emergency cannulation and/or intubation over the 5-year period. This service review indicates that general anesthesia for outpatient dental anesthesia may be safely performed without mandatory IV access. The technique employed in this center emphasizes the need for the clinician to primarily concentrate on pediatric airway management in a safe environment with experienced assistance. It supports the hypothesis that instrumentation of the airway (insertion of laryngeal mask airway) can be satisfactorily achieved without prior IV access.

The prevalence of albuminuria in dogs and cats in an ICU or recovering from anesthesia

To evaluate the prevalence of albuminuria in dogs and cats admitted to the ICU or recovering from an anesthetic event. Prospective clinical study over a 10-week period in 2003. Veterinary teaching hospital. One hundred and five dogs and 22 cats. Urine was collected from dogs and cats admitted to the ICU or recovering from an anesthetic event. When possible, a second urine sample was collected approximately 48 hours later from those animals that had albuminuria during the initial screening. All dog samples and most cat samples were screened for albumin using a commercial point-of-care immunoassay. Aliquots of samples that tested positive were stored at -20 °C until subsequent albumin quantification via antigen capture ELISA. Albuminuria was detected in 63 of 105 (60.0%) dogs and in 14 of 22 (63.6%) cats; the prevalence was higher in animals admitted to ICU than in those recovering from anesthesia. In subsequent samples from 26 dogs, urine albumin decreased in 20 (76.9%) when compared with the first sample; urine albumin was undetectable in 5 (19.2%). In subsequent samples from 6 cats, 4 (66.7%) had decreases in urine albumin when compared with the first sample; 1 (16.7%) was negative for urine albumin. Eleven of 12 dogs (91.7%) and 3 of 4 cats (75%) that died within 3 days of admission to the ICU had abnormal urine albumin; whereas 52 of 93 (55.9%) and 11 of 18 (61.1%) dogs and cats, respectively, who survived more than 3 days had abnormal urine albumin. Dogs with albuminuria were at increased risk of death. The prevalence of albuminuria in animals admitted to the ICU or recovering from anesthesia is higher than reported previously and transient in some patients. The presence of albuminuria may be a negative prognostic indicator in this population.