Failure of Sedasys: Destiny or Poor Design?

Remimazolam and Its Place in the Current Landscape of Procedural Sedation and General Anesthesia

Remimazolam was derived from its parent compound by adding an ester linkage into its structure so that the drug becomes a substrate for ester metabolism. As a result, it undergoes organ-independent ester hydrolysis, although the clinical benefits in terms of shorter recovery are not uniformly observed in clinical practice. Remimazolam is mainly tested in procedural sedation. In comparison to propofol, the current gold standard for procedural sedation, its proposed attractiveness is shorter wake-up times and a clear-headed recovery. Its clear advantages over propofol are better hemodynamic stability, lack of pain on injection and availability of a reversal agent in the form of flumazenil. Data on patient and proceduralist satisfaction are lacking. Remimazolam is also used for induction and maintenance of general anesthesia in Japan (where it is approved for this purpose). In this scenario, it is not clear if it can achieve the same degree of lack of recall as propofol. The use of remimazolam in obstetrics, pediatrics and high-risk populations is an emerging area.

Closed-loop anesthesia: foundations and applications in contemporary perioperative medicine

A closed-loop automatically controls a variable using the principle of feedback. Automation within anesthesia typically aims to improve the stability of a controlled variable and reduce workload associated with simple repetitive tasks. This approach attempts to limit errors due to distractions or fatigue while simultaneously increasing compliance to evidence based perioperative protocols. The ultimate goal is to use these advantages over manual care to improve patient outcome. For more than twenty years, clinical studies in anesthesia have demonstrated the superiority of closed-loop systems compared to manual control for stabilizing a single variable, reducing practitioner workload, and safely administering therapies. This research has focused on various closed-loops that coupled inputs and outputs such as the processed electroencephalogram with propofol, blood pressure with vasopressors, and dynamic predictors of fluid responsiveness with fluid therapy. Recently, multiple simultaneous independent closed-loop systems have been tested in practice and one study has demonstrated a clinical benefit on postoperative cognitive dysfunction. Despite their advantages, these tools still require that a well-trained practitioner maintains situation awareness, understands how closed-loop systems react to each variable, and is ready to retake control if the closed-loop systems fail. In the future, multiple input multiple output closed-loop systems will control anesthetic, fluid and vasopressor titration and may perhaps integrate other key systems, such as the anesthesia machine. Human supervision will nonetheless always be indispensable as situation awareness, communication, and prediction of events remain irreplaceable human factors.

Robotic Anesthesia: A Vision for 2050

The last 2 decades have brought important developments in anesthetic technology, including robotic anesthesia. Anesthesiologists titrate the administration of pharmacological agents to the patients' physiology and the needs of surgery, using a variety of sophisticated equipment (we use the term "pilots of the human biosphere"). In anesthesia, increased safety seems coupled with increased technology and innovation. This article gives an overview of the technological developments over the past decades, both in terms of pharmacological and mechanical robots, which have laid the groundwork for robotic anesthesia: target-controlled drug infusion systems, closed-loop administration of anesthesia and sedation, mechanical robots for intubation, and the latest development in the world of communication with the arrival of artificial intelligence (AI)-derived chatbots are presented.

Pharmacokinetic and pharmacodynamic drug display and simulation systems in anesthesia practice

PURPOSE OF REVIEW

This review explores the use of tools and displays based on pharmacokinetic and pharmacodynamic (PK/PD) modelling of drugs used in anesthesia. The primary focus is on those tools designed to illustrate the interactions between two or more drugs, or classes of drugs, and in particular, their use in a real-time clinical support role. Off-line, educational tools are also explored.

RECENT FINDINGS

Despite initial promise and encouraging supporting data, the use of real-time display of PK/PD is not common except in target-controlled infusion (TCI) pumps.

SUMMARY

PK/PD simulation is a useful tool for exposition of the relationship between drug dosing and effect. The initial promise of real-time tools has yet to be realized in routine clinical practice.

Sedation-analgesia techniques for nonoperating room anesthesia: an update

PURPOSE OF REVIEW

There has been a substantial increase in nonoperating room anesthesia procedures over the years along with an increase in the complexity and severity of cases. These procedures pose unique challenges for anesthesia providers requiring meticulous planning and attention to detail. Advancements in the delivery of sedation and analgesia in this setting will help anesthesia providers navigate these challenges and improve patient safety and outcomes.

RECENT FINDINGS

There has been a renewed interest in the development of newer sedative and analgesic drugs and delivery systems that can safely provide anesthesia care in challenging situations and circumstances.

SUMMARY

Delivery of anesthesia care in nonoperating room locations is associated with significant challenges. The advent of sedative and analgesic drugs that can be safely used in situations where monitoring capabilities are limited in conjunction with delivery systems, that can incorporate unique patient characteristics and ensure the safe delivery of these drugs, has the potential to improve patient safety and outcomes. Further research is needed in these areas to develop newer drugs and delivery systems.

Quo Vadis Anesthesiologist? The Value Proposition of Future Anesthesiologists Lies in Preserving or Restoring Presurgical Health after Surgical Insult

This Special Issue of the Journal of Clinical Medicine is devoted to anesthesia and perioperative care [...].

Sedation/analgesia techniques for nonoperating room anesthesia: new drugs and devices

PURPOSE OF REVIEW

The purpose of this article is to review new drugs and devices for nonoperating room anesthesia (NORA).

RECENT FINDINGS

Remimazolam is an ultra-short-acting, water-soluble intravenous benzodiazepine with a fast onset and offset that has been approved recently for use in procedural sedation. Phase III trials have established the effectiveness of remimazolam sedation compared with placebo and midazolam in gastrointestinal endoscopy and bronchoscopy. More research is required investigating remimazolam in real-world NORA settings, including comparisons with propofol sedation. Oliceridine is a μ-agonist with selectivity for the G protein pathway and low potency for β-arrestin recruitment. As such it may be associated with less nausea, vomiting and respiratory depression than traditional opioids used. Although no studies have been published about oliceridine use in NORA to date, results from surgical studies indicate a potential place in nonoperating room practice. Research continues into alternative methods of drug delivery, such as patient-controlled sedation but no new devices are described.

SUMMARY

Further studies are required before these new drugs and devices are embraced in NORA.

Emerging Approaches in Intravenous Moderate and Deep Sedation

Successful pharmacological innovations that have made a difference in daily practice are rare in the world of anesthesia and sedation. After many years of research, it seems that we finally have two new drug innovations that are likely to change the paradigm of moderate and deep sedation. These are oliceridine and remimazolam. Both have been in development for over a decade. Oliceridine was synthesized in a lab as an entirely new molecule. It is a biased μ- receptor agonist that acts preferentially on the G-protein pathway (which is responsible for analgesia). At least in lower doses, it has minimal effect on the beta-arrestin pathway, which is responsible for unwanted effects of μ-opioid receptor activation such as respiratory depression and gastrointestinal dysfunction. Like any other μ- receptor agonist, it produces appropriate dose-dependent analgesia. Remimazolam is structurally similar to midazolam; however, it has an additional ester linkage that delivers the kinetics of remifentanil. As a result, while pharmacodynamically identical to midazolam, remimazolam is metabolized by ester hydrolysis and subsequently its elimination is rapid and predictable. The present review discusses the two drugs in detail with a particular emphasis on their potential role in moderate and deep sedation.

Patient-maintained propofol sedation for adult patients undergoing surgical or medical procedures: a scoping review of current evidence and technology

Patient-maintained propofol sedation (PMPS) is the delivery of procedural propofol sedation by target-controlled infusion with the patient exerting an element of control over their target-site propofol concentration. This scoping review aims to establish the extent and nature of current knowledge regarding PMPS from both a clinical and technological perspective, thereby identifying knowledge gaps to guide future research. We searched MEDLINE, EMBASE, and OpenGrey databases, identifying 17 clinical studies for analysis. PMPS is described in the context of healthy volunteers and in orthopaedic, general surgical, dental, and endoscopic clinical settings. All studies used modifications to existing commercially-available infusion devices to achieve prototype systems capable of PMPS. The current literature precludes rigorous generalisable conclusions regarding the safety or comparative clinical effectiveness of PMPS, however cautious acknowledgement of efficacy in specific clinical settings is appropriate. Based on the existing literature, together with new standardised outcome reporting recommendations for sedation research and frameworks designed to assess novel health technologies research, we have made recommendations for future pharmacological, clinical, behavioural, and health economic research on PMPS. We conclude that high-quality experimental clinical trials with relevant comparator groups assessing the impact of PMPS on standardised patient-orientated outcome measures are urgently required.

Oliceridine and its potential to revolutionize GI endoscopy sedation

Providing sedation to patients undergoing gastrointestinal (GI) endoscopy is a controversial and emotive issue. The mainstay of sedation is propofol, whose administration is within the sole jurisdiction of anesthesia providers, at least in the USA. Attempts have been made to seize the authority by the GI community. One of the first attempts was the use of the prodrug of propofol -fospropofol. However, as the drug has a similar adverse effect profile as propofol in terms of respiratory depression, the FDA did not approve its use by providers other than those trained in airway management. Sedasys® was the next attempt, which was a computer-assisted personalized sedation system. As a result of insufficient sedation that could be provided with the device, although very successful in research settings, it was not a commercial success. It seems that remimazolam is the next effort in this direction. It is likely to fail in this regard unless its respiratory depressant properties and failure rates could be addressed. G protein-biased μ-receptor agonists are a new class of opioids exhibiting analgesic properties similar to morphine without equivalent respiratory depressant properties. Oliceridine is the prototype. As a result, the drug can be additive to midazolam or remimazolam and allow screening colonoscopy to be comfortably completed without the need for propofol. For an anesthesia provider, the administration of oliceridine can eliminate the need for drugs such as fentanyl that add to the respiratory depressant properties of propofol. As a result, oliceridine has the potential to render the sedation for GI endoscopy procedures both safe and cost-effective.

Medical, Political, and Economic Considerations for the Use of MAC for Endoscopic Sedation: Big Price, Little Justification?

The last few decades of gastrointestinal (GI) endoscopy have seen phenomenal growth. In many aspects, GI endoscopy has led the field of nonsurgical interventional medicine. In many aspects, this growth is facilitated by advancements in sedation-both drugs and techniques. Unfortunately, the topic of GI endoscopy sedation is also mired in many controversies, mainly emanating from the cost of anesthesia providers. While no one debates their role in the majority of advanced endoscopic procedures, the practice of universal propofol sedation in the USA, delivered by anesthesia providers, needs a closer look. In this review, medical, political, and economic considerations of this important topic are discussed in a very frank and honest way. While such ubiquitous propofol use has increased satisfaction of both patients and gastroenterologists, there is little justification. More importantly, going by the evidence, there is even less justification for the mandated anesthesia providers use for such delivery. Unfortunately, the FDA could not be convinced otherwise. The new drug fospropofol met the same fate. Approval of SEDASYS^®, the first computer-assisted personalized sedation system, was a step in the right direction, nevertheless an insufficient step that failed to takeoff. As a result, in spite of years of research and efforts of many august societies, the logjam of balancing cost and justification of propofol sedation has continued. We hope that recent approval of remimazolam, a novel benzodiazepine, and potential approval of oliceridine, a novel short-acting opioid, might be able to contain the cost without compromising the quality of sedation.

Critical Analysis of Guidelines for Providing Sedation to Patients Undergoing Gastrointestinal Endoscopy Procedures

In spite of growing numbers of gastrointestinal endoscopic procedures performed under deep sedation, guidelines are lacking. Hypoxemia and aspiration continue to be the main source of morbidity. Anesthesia providers have tried to address these concerns by modifying their technique and employing newer or improvised devices. In addition, preprocedural evaluation poses many challenges. In many centers, workload pressures determine the time available to perform such an evaluation. A comprehensive history and examination similar to a major surgical procedure is often not possible. As a result, a focused history and examination is essential. This should be followed by an appropriate explanation of risks before obtaining consent. A plan should be in place to manage complications such as aspiration. This paper provides a succinct review of the above aspects.

Recent advances in intravenous anesthesia and anesthetics

Anesthesiology, as a field, has made promising advances in the discovery of novel, safe, effective, and efficient methods to deliver care. This review explores refinement in the technology of soft drug development, unique anesthetic delivery systems, and recent drug and device failures.