An unexplained death: Hannah Greener and chloroform

Preoperative fasting and the risk of pulmonary aspiration-a narrative review of historical concepts, physiological effects, and new perspectives

In the early days of anaesthesia, the fasting period for liquids was kept short. By the mid-20th century 'nil by mouth after midnight' had become routine as the principles of the management of 'full stomach' emergencies were extended to include elective healthy patients. Back then, no distinction was made between the withholding of liquids and solids. Towards the end of the last century, recommendations of professional anaesthesiology bodies began to reduce the fasting time of clear liquids to 2 h. This reduction in fasting time was based on the understanding that gastric emptying of clear liquids is rapid, exponential, and proportional to the current filling state of the stomach. Furthermore, there was no evidence of a link between drinking clear liquids and the risk of aspiration. Indeed, most instances of aspiration are caused by failure to identify aspiration risk factors and adjust the anaesthetic technique accordingly. In contrast, long periods of liquid withdrawal cause discomfort and may also lead to serious postoperative complications. Despite this, more than two decades after the introduction of the 2 h limit, patients still fast for a median of up to 12 h before anaesthesia, mainly because of organisational issues. Therefore, some hospitals have decided to allow patients to drink clear liquids within 2 h of induction of anaesthesia. Well-designed clinical trials should investigate whether these concepts are safe in patients scheduled for anaesthesia or procedural sedation, focusing on both aspiration risk and complications of prolonged fasting.

An update on the mechanisms and risk factors for anesthesia-related cardiac arrest in children: a narrative review

The relationship between surgery and anesthesia safety in children and the country's Human Development Index (HDI) value has been described previously. The aim of this narrative review was to provide an update on the mechanisms and risk factors of Anesthesia-Related Cardiac Arrest (ARCA) in pediatric surgical patients in countries with different HDI values and over time (pre-2001 vs. 2001‒2024). Electronic databases were searched up to March 2024 for studies reporting ARCA events in children. HDI values range from 0 to 1 (very-high-HDI countries: ≥ 0.800, high-HDI countries: 0.700‒0.799, medium-HDI countries: 0.550‒0.699, and low-HDI countries: < 0.550). Independent of time, the proportion of children who suffered perioperative Cardiac Arrest (CA) attributed to anesthesia-related causes was higher in very-high-HDI countries (50%) than in countries with HDI values less than 0.8 (15%‒36%), but ARCA rates were higher in countries with HDI values less than 0.8 than in very-high-HDI countries. Regardless of the HDI value, medication-related factors were the most common mechanism causing ARCA before 2001, while cardiovascular-related factors, mainly hypovolemia, and respiratory-related factors, including difficulty maintaining patent airways and adequate ventilation, were the major mechanisms in the present century. Independent of HDI value and time, a higher number of ARCA events occurred in children with heart disease and/or a history of cardiac surgery, those aged younger than one year, those with ASA physical status III‒V, and those who underwent emergency surgery. Many ARCA events were determined to be preventable. The implementation of specialized pediatric anesthesiology and training programs is crucial for anesthesia safety in children.

Nanotherapeutics for Alleviating Anesthesia-Associated Complications

Current management of anesthesia-associated complications falls short in terms of both efficacy and safety. Nanomaterials with versatile properties and unique nano-bio interactions hold substantial promise as therapeutics for addressing these complications. This review conducts a thorough examination of the existing nanotherapeutics and highlights the strategies for developing prospective nanomedicines to mitigate anesthetics-related toxicity. Initially, general, regional, and local anesthesia along with the commonly used anesthetics and related prevalent side effects are introduced. Furthermore, employing nanotechnology to prevent and alleviate the complications of anesthetics is systematically demonstrated from three aspects, that is, developing 1) safe nano-formulization for anesthetics; 2) nano-antidotes to sequester overdosed anesthetics and alter their pharmacokinetics; 3) nanomedicines with pharmacodynamic activities to treat anesthetics toxicity. Finally, the prospects and challenges facing the clinical translation of nanotherapeutics for anesthesia-related complications are discussed. This work provides a comprehensive roadmap for developing effective nanotherapeutics to prevent and mitigate anesthesia-associated toxicity, which can potentially revolutionize the management of anesthesia complications.

[The Stadium analgeticum - Historical Highlights on the Ether Rush]

For decades, the term ether rush was synonymous with the practice of short-term anaesthesia, among patients and doctors. The term was first used shortly after the discovery of the anaesthetic properties of ether by Hamburg-based physician Elias Salomon Nathan in an article about the newly discovered ether anaesthesia. Decades later, the surgeon Paul Sudeck, who also worked in Hamburg, also described an anaesthetic technique he practiced as an ether rush and met with great approval from his surgical colleagues, as well as for his anaesthetic mask developed for carrying out the ether rush and the anaesthetic dropper, specified for this purpose.Sudeck did not want to be regarded as the inventor of the special anaesthetic technique and repeatedly pointed out that his procedure had already been described and applied before him, but was forgotten again. Nevertheless, Sudeck's ether rush remained a well-known, widespread analgesic method in German-speaking countries until the end of the 1940s, and it proved its worth many times during the World War. After 1945, when ether lost its pre-dominant role as an inhalation anaesthetic and was replaced by other, new agents and short-acting i. v. administered analgesics, the ether rush was also fell into oblivion and was no longer used.Against the background of the first successfully performed ether anaesthesia on October 16th, 1846 - 175 years ago - at the Massachusetts General Hospital in Boston, the description of the ether rush should be recalled in this context.

Dex® carbohydrate drinks in trauma patients fasting preoperatively – A patient satisfaction study

Introduction

Dex® is an alkaline carbohydrate (CHO) drink used preoperatively in patients fasting for elective surgery. Its utilisation in patients awaiting emergency surgery is yet to be ascertained. We undertook a study assessing patient satisfaction relating to the introduction of Dex® in trauma patients in a Level 1 adult trauma centre.

Methods

Patients fasting for surgery, and able to receive clear fluids in compliance with local guidelines, were eligible for inclusion. Patient satisfaction scores for predetermined variables were recorded via an interval observer scale prior to and following the introduction of Dex® to the trauma unit.

Results

Prior to the introduction of Dex® 14 satisfaction evaluations were completed. A further 13 evaluations were returned after Dex® was made available. Post-traumatic amnesia accounted for some patients being unable to complete the evaluation. Patients who completed the satisfaction evaluations after Dex® was introduced reported higher satisfaction in all but two variables (‘Headache’ and ‘Staff Annoyance’). ‘Hunger’ median scores were 7 (95% CI, 5–8) prior to the introduction of Dex® and 3 (95% CI, 2–6) after its’ introduction ( p = .004). ‘Thirst’ median scores were 7.5 (95% CI, 6–10) and 4 (95% CI, 3–8) prior to and after Dex® introduction, respectively ( p = .018).

Conclusion

No adverse events or theatre timing related issues were associated with the use of Dex®. A larger randomised study of CHO drink supplementation in trauma patients fasting preoperatively is warranted to further evaluate these satisfaction endpoints as well as the other variables investigated in this study. Postoperative evaluation of these markers should also be considered.

Anesthesiologist-related factors associated with risk-adjusted pediatric anesthesia-related cardiopulmonary arrest: a retrospective two level analysis

BACKGROUND

Pediatric anesthesia-related cardiac arrest is an uncommon but catastrophic adverse event which has been, in a previous study, associated with anesthesiologist-related factors such as number of days per year providing pediatric anesthesia. We aimed to replicate this and assess other anesthesiologist-related risk factors for anesthesia-related cardiac arrest after adjusting for known underlying risk factors present in the case mix.

METHODS

We analyzed a large retrospectively collected patient cohort of anesthetics administered from 2006 to 2016 to children at a tertiary pediatric hospital. Three reviewers independently reviewed cardiac arrests and categorized whether they appeared to be related to anesthesia care. Anesthesiologist-related factors including academic rank, experience, recent case mix, and days per year delivering pediatric anesthesia were assessed for association with anesthesia-related cardiac arrest after adjustment for underlying case mix.

RESULTS

Cardiac arrest occurred in 240 of 109 775 anesthetics (incidence 22/10 000 anesthetics); 82 (7/10 000 anesthetics) were classified as anesthesia-related. In univariable analyses, anesthesia-related cardiac arrest was associated with age, (infants ≤180 days, p < .001) American Society of Anesthesiologists Physical Status, (>2, p < .001) American Society of Anesthesiologists Physical Status Emergency, (p = .0035) cardiac surgery, (p < .001) operating room location, (p = .0066) and resident/fellow supervision, (p = .009) but none of the anesthesiologist factors. Even after adjusting for age and American Society of Anesthesiologist Status, none of the anesthesiologist factors were associated with anesthesia-related cardiac arrest.

CONCLUSIONS

Case mix explained all associations between higher risk of pediatric anesthesia-related cardiac arrest and anesthesiologist-related variables at our institution.

Practical considerations for creating a strategic and proactive clinical safety and pharmacovigilance organization for the future

BACKGROUND:

In 2012, Patient Safety (PS) in AstraZeneca was facing a situation with multiple challenges, scientifically and structurally.

OBJECTIVE:

To meet these and support AstraZeneca’s ambition to return to growth after years of patent expiry, we undertook a project to fundamentally revisit ways of working to create an organisation set up to provide strategic safety in support of drug project decision-making.

METHOD:

In this paper, we describe the challenges we faced, the project to deliver changes to respond to them, and the methodology used. The project had two main components: creating a new operating model and simplifying the procedural framework.

RESULTS:

It was delivered in a focused effort by internal PS resources with cross-functional input. The framework simplification resulted in a 71% reduction in procedural documents and a survey of PS staff revealed an increase in satisfaction of 10%–20% across all scores.

CONCLUSIONS:

With >3 years of observation time, this project has provided AstraZeneca with a PS organisation able to provide strategic safety, supporting successful portfolio delivery, while ensuring patient safety and maintaining compliance with global pharmacovigilance regulations. It has driven efficiency and set the foundation for continued organisational evolution to meet future business needs in an everchanging environment.

The Obese Patient: Facts, Fables, and Best Practices

The prevalence of obesity continues to rise worldwide, and anesthesiologists must be aware of current best practices in the perioperative management of the patient with obesity. Obesity alters anatomy and physiology, which complicates the evaluation and management of obese patients in the perioperative setting. Gastric point-of-care ultrasound (PoCUS) is a noninvasive tool that can be used to assess aspiration risk in the obese patient by evaluating the quantity and quality of gastric contents. An important perioperative goal is adequate end-organ perfusion. Standard noninvasive blood pressure (NIBP) is our best available routine surrogate measurement, but is vulnerable to greater inaccuracy in patients with obesity compared to the nonobese population. Current NIBP methodologies are discussed. Obese patients are at risk for wound and surgical site infections, but few studies conclusively guide the exact dosing of intraoperative prophylactic antibiotics for them. We review evidence for low-molecular-weight heparins and weight-based versus nonweight-based administration of vasoactive medications. Finally, intubation and extubation of the patient with obesity can be complicated, and evidence-based strategies are discussed to mitigate danger during intubation and extubation.

The evolution of pediatric sedation and anesthesia patient safety: An interview with Dr Charles J. "Charlie" Coté

The career of Dr Charles J. Coté covered a period of major advances in pediatric anesthesia patient safety. Dr Coté (1946 --), Professor Emeritus in Anaesthesia at Harvard Medical School, helped develop pediatric sedation guidelines, conducted influential clinical research, edited a major textbook, and promoted pediatric anesthesia training fellowships in low- and middle-income countries. Based on a series of interviews with Dr Coté, this article reviews the career of this Robert M. Smith Award winner through the lens of improvements in pediatric sedation and anesthesia patient safety.

An Anglocentric History of Anaesthetics and Analgesics in the Refinement of Animal Experiments

Previous histories of animal experimentation, e.g., Franco (2013) have focused on ethics, the law and the personalities involved, but not on the involvement of anaesthetics or analgesics. Given that these were major subjects of (UK) Parliamentary debates on vivisection in the mid-19th century and viewed as "indisputable refinements in animal experimentation" (Russell and Burch 1959), it seemed that an analysis of their role was overdue. This commentary has, in interweaving the history of animal experimentation in the UK with the evolution of anaesthesia, attempted to: (1) clarify the evidence for Russell and Burch's view; and (2) evaluate anaesthesia's ongoing contribution to experimental refinement. The history that emerges reveals that the withholding or misuse of anaesthetics and, or analgesics from laboratory animals in the UK has had a profound effect on scientists and indirectly on the attitudes of the British public in general, becoming a major driver for the establishment of the anti-vivisection movement and subsequently, the Cruelty to Animals Act (1876)-the world's first legislation for the regulation of animal experimentation. In 1902, the mismanaged anaesthetic of a dog in the Department of Physiology, University College London resulted in numerous events of public disorder initiated by medical students against the police and a political coalition of anti-vivisectionists, trade unionists, socialists, Marxists, liberals and suffragettes. The importance of anaesthesia in animal experiments was sustained over the following 150 years as small mammalian species gradually replaced dogs and cats as the principle subjects for vivisection. In discussing experimental refinement in their 1959 report, "The Principles of Humane Experimental Technique" Russell and Burch described anaesthetics as "… the greatest single advance in humane technique, (which) has at the same time been virtually indispensable for the advance of experimental biology". Since then, the role of anaesthetics and in particular analgesics has become an unavoidable consideration whenever animal experiments are planned and conducted. This has been accompanied by a proliferation of training and educational programmes in laboratory animal anaesthesia.

Quality Anesthesia

Quality has been defined by six domains: effective, equitable, timely, efficient, safe, and patient centered. Quality of anesthesia care can be improved through measurement, either through local measures in quality improvement or through national measures in value-based purchasing programs. Death directly related to anesthesia care has been reduced, but must be measured beyond simple mortality. To improve perioperative care for our patients, we must take shared accountability for all surgical outcomes including complications, which has traditionally been viewed as being surgically related. Anesthesiologists can also impact public health by being engaged in improving cognitive recovery after surgery and addressing the opiate crisis. Going forward, we must focus on what patients want and deserve: improved patient-oriented outcomes and satisfaction with our care. By listening to our patients and being engaged in the entire perioperative process, we can make the greatest impact on perioperative care.

Professor Ross Holland: The Special Committee Investigating Deaths Under Anaesthesia (SCIDUA) and his other contributions to anaesthesia

As a young anaesthetic trainee in 1959 Ross Holland persuaded the Minister of Health in NSW, Australia, to establish SCIDUA, which by law required compulsory reporting for all deaths occurring during anaesthesia or up to 24 hours after cessation of the anaesthetic. The committee was multidisciplinary and, most importantly, had statutory privilege so that no discussions or findings were able to be subpoenaed for other legal investigations or case law. Holland was the foundation secretary of SCIDUA and later Chair. Apart from three years in the 1980s when there were political issues with legal privilege, the committee has met monthly and still meets. Holland was a major figure in antipodean anaesthesia, setting up in 1978 the clinical department at Westmead Hospital Sydney, then in 1987 becoming the foundation Professor to the Department of Anaesthesiology at the University of Hong Kong, and in 1990 foundation Professor and Chair, Department of Anaesthesia and Intensive Care at the University of Newcastle, NSW. Holland had strong historical interests and was responsible for founding the Society for the Preservation of Artefacts of Surgery and Medicine (SPASM) and its associated museum. He also served an important term as Dean of the Faculty of Anaesthetists, Royal Australasian College of Surgeons prior to that Faculty becoming independent as the Australian and New Zealand College of Anaesthetists (ANZCA). Professor Holland received many accolades for these activities during his life, which are noted. It is fitting to recognise his seminal contributions to patient safety over more than 50 years.

Of Penguins, Pinnipeds, and Poisons: Anesthesia on Elephant Island

Although Ernest Shackleton's Endurance Antarctic expedition of 1914 to 1916 is a famous epic of survival, the medical achievements of the two expedition doctors have received little formal examination. Marooned on Elephant Island after the expedition ship sank, Drs. Macklin and McIlroy administered a chloroform anesthetic to crew member Perce Blackborow to amputate his frostbitten toes. As the saturated vapor pressure of chloroform at 0°C is 71.5 mmHg and the minimum alveolar concentration is 0.5% of sea-level atmospheric pressure (3.8 mmHg), it would have been feasible to induce anesthesia at a low temperature. However, given the potentially lethal hazards of a light chloroform anesthetic, an adequate and constant depth of anesthesia was essential. The pharmacokinetics of the volatile anesthetic, administered via the open-drop technique in the frigid environment, would have been unfamiliar to the occasional anesthetist. To facilitate vaporization of the chloroform, the team burned penguin skins and seal blubber under overturned lifeboats to increase the ambient temperature from -0.5° to 26.6°C. Chloroform degrades with heat to chlorine and phosgene, but buildup of these poisonous gases did not occur due to venting of the confined space by the stove chimney. The anesthetic went well, and the patient-and all the ship's crew-survived to return home.

A history of pediatric anesthesia: a tale of pioneers and equipment

The history of pediatric anesthesia is fascinating in terms of how inventive anesthesiologists became over time to address the needs for advances in surgery. We have many pioneers and heroes. We hope you will enjoy this brief overview and that we have not left out any of the early contributors to our speciality. Obviously there is insufficient space to include everyone.

Gum chewing during pre-anesthetic fasting

Many ad hoc fasting guidelines for pre-anesthetic patients prohibit gum chewing. We find no evidence that gum chewing during pre-anesthetic fasting increases the volume or acidity of gastric juice in a manner that increases risk, nor that the occasional associated unreported swallowing of gum risks subsequent aspiration. On the contrary, there is evidence that gum chewing promotes gastrointestinal motility and physiologic gastric emptying. Recommendations against pre-anesthetic gum chewing do not withstand scrutiny and miss an opportunity to enhance comfort and sense of wellbeing for patients awaiting anesthesia. Gum chewing during the pre-anesthetic nil per os (NPO) period would also permit the development of gum-delivered premedications and should be permitted in children old enough to chew gum safely. Gum chewing should cease when sedatives are given and all patients should be instructed to remove any chewing gum from the mouth immediately prior to anesthetic induction.

Anaesthesia and high altitude: a history

During an expedition to climb Everest in 1933, expedition doctor Raymond Greene administered an open-drop chloroform anaesthetic to a Tibetan patient at an altitude of more than 14,000 feet. The patient's subsequent apparent cardiopulmonary arrest has long been attributed to the effects of altitude on anaesthetic delivery. However, anaesthetics can be safely administered at a wide variety of altitudes by adequately trained and experienced anaesthetists. The problems may have arisen from an inadequate depth of anaesthesia consequent to decreased chloroform vaporisation in a cold environment, Greene's concern about potential depression of ventilation and the contemporary lack of a precise approach to assessing depth of anaesthesia.

Outcomes of pediatric anesthesia

Improvement in anesthesia outcomes has derived from advances in safety science related to equipment, drugs, human factors analysis, professional standardization and organization, subspecialty care, and regionalization. Outcomes of pediatric anesthesia have improved, but universal outcome measures are lacking. Because of the limitations of small numbers, future improvement efforts will necessarily involve multiple disciplines, institutions, and regions, and will require sophisticated systems approaches.

In vitro modulation of HERG channels by organochlorine solvent trichlormethane as potential explanation for proarrhythmic effects of chloroform

Acute chloroform intoxication can cause depression of the central nervous system and may lead to death from lethal arrhythmias or respiratory arrest. Thus, the organic solvent is no longer in clinical use as an anaesthetic, but still plays a role in cases of suicide, homicide or inhalation for psychotropic effects. Several cases of lethal arrhythmia after intoxication with chloroform have been described. Pharmacological inhibition of cardiac "human ether-à-go-go-related gene" (HERG) potassium channels is linked to proarrhythmic effects of cardiac and noncardiac drugs. To further investigate the electrophysiological basis of the arrhythmogenic potential of chloroform, we analysed inhibitory effects of chloroform on cloned HERG potassium channels, heterologously expressed in Xenopus oocytes and in Human Embryonic Kidney (HEK 293) cells using the double-electrode voltage-clamp technique and the whole-cell patch-clamp technique, respectively. In HEK cells, chloroform blocked HERG tail currents with an IC(50) of 4.97mM. Biophysical properties were further investigated in the Xenopus oocyte expression system. Onset and wash-out of block was fast and inhibition was completely reversible. Chloroform did not alter channel activation, however, direct channel inactivation was accelerated significantly. Steady-state-inactivation of HERG was not affected. Chloroform dependent block of HERG channels was voltage dependent with a decrease of inhibition at more positive membrane potentials. No frequency-dependence of block could be observed. In summary, chloroform blocked HERG potassium channels probably in a toxicologically relevant concentration. These findings contribute to the pathophysiology of proarrhythmic effects in acute chloroform intoxication.

Dealing With a Deluge of Data: An Assessment of Adverse Event Data on North Central Cancer Treatment Group Trials

Purpose

Adverse events (AEs) are monitored in clinical trials for patient safety, to satisfy reporting requirements, and develop safety profiles. Recently, much attention has been placed on the reporting of serious AEs (SAEs) that are either life threatening or lethal in clinical trials. However, SAEs comprise a small subset of all AE data collected for trials; the majority of AE data collected are routine AEs (RAEs) regarding non–life-threatening events. We assessed the utility of the RAE data collected, relative to the volume.

Patients and Methods

We surveyed the RAE data from 26 North Central Cancer Treatment Group coordinated trials.

Results

A total of 8,318 (11%) of 75,598 of RAEs required queries. Of these, 86% were protocol-required RAEs, 83% of RAEs required per protocol were within normal limits (eg, platelets) or not present, and 61% of extra AEs were mild. One fifth of RAEs were considered unlikely to be related or unrelated to treatment. Overall, 3% of events were severe, life threatening, or caused death. Only 1% of RAE data reported required expedited reporting (eg, via Adverse Event Expedited Reporting System). Results indicate that 72% of RAEs would be eliminated if only the maximum severity per patient and type were required. These results were validated in a large phase III trial.

Conclusion

The majority of RAEs identified, transcribed, and entered are not clinically important. Our data suggest that reducing the number of AEs monitored will affect substantially neither overall patient safety nor compromise evaluation of regimens undergoing testing. We present several considerations for such a reduction in data collection, as well as a policy that we have used to address the deluge of RAE data.