What Is the Role of Dexmedetomidine in Modern Anesthesia and Critical Care?

Dexmedetomidine's unique sedative properties have led to its widespread use. Dexmedetomidine has a beneficial pharmacologic profile including analgesic sparing effects, anxiolysis, sympatholysis, organ-protective effects against ischemic and hypoxic injury, and sedation which parallels natural sleep. An understanding of predictable side effects, effects of age-related physiologic changes, and pharmacokinetic and pharmacodynamic effects of dexmedetomidine is crucial to maximize its safe administration in adults and children. This review focuses on the growing body of literature examining advances in applications of dexmedetomidine in children and adults.

Human Factors Evaluation of the Universal Anaesthesia Machine: Assessing Equipment with High-Fidelity Simulation Prior to Deployment in a Resource-Constrained Environment.

BACKGROUND: Anesthesia providers in low- and middle-income countries face many challenges, including poor availability of functioning equipment designed to meet their environmental, organizational, and resource constraints. These are serious global health disparities which threaten access to care and patient safety for those who receive surgical care. In this study, we conducted a simulation-based human factors analysis of the Universal Anaesthesia Machine (UAM®), a device designed to support anesthesia providers in austere medical settings. Our team anticipated the introduction of the UAM® to the two major referral hospitals in Freetown, Sierra Leone. A prior observational study had identified these two hospitals as having environmental conditions consistent with an austere environment: an unstable electrical grid, as well as limited access to compressed oxygen, biomedical support, and consumables. Although the Baltimore simulation environment cannot reproduce all of the challenges present in a resource-constrained environment such as Sierra Leone, the major impediments to standard anesthesia machine functionality and human factors-associated use can be reproduced with the use of high-fidelity simulation. Using anesthesia care providers who have limited UAM® familiarity, this study allowed for the examination of machine-user issues in a controlled environment in preparation for further field studies concerning equipment introduction, training and device deployment in Sierra Leone. The goals of this study were: 1. to assess the usability of the UAM® (machine-user interface, simulated patient use, symbology, etc.) across different provider user groups during simulation of use in scenarios depicting routine use in healthy patients, use in clinically challenging patients and use in environmentally-challenging scenarios in a controlled setting devoid of patient risk, and 2. To gather feedback on available UAM manuals and cognitive aides and UAM usability issues in order to guide development of curricula for training providers on use of the UAM® in the intended austere clinical environments. METHODS: Residents, fellows, attending physician anesthesiologists, student nurse anesthetists, and nurse anesthetists participated in a variety of simulations involving the Universal Anaesthesia Machine® at the Johns Hopkins Medicine Simulation Center between September 2012 and July 2013. Data collected included participant demographics, performance during simulation scenarios captured with critical action checklists, workload ratings captured with the National Aeronautics and Space Administration Task Load Index (NASA TLX), and participant reactions to UAM® use captured through a post-session survey and semi-structured usability debriefing. The scenarios were: 1. normal use (machine check, induction, and maintenance of an uneventful case), 2. use in a challenging clinical condition (acute onset of bronchospasm) and 3.use in an adverse environmental event (power failure). Critical action checklists and workload ratings were analyzed by Analysis of Covariance (ANCOVA) to control for participant demographics. Usability debriefings were analyzed qualitatively. RESULTS: Thirty-five anesthesia providers participated in the study. Overall participant ratings, observations of performance in simulation scenarios, and usability debriefings indicated a high level of usability for the UAM®. Mean participant ratings were high for ease of use (5.4 ± 0.96) and clarity of instruction (6.2 ± 0.87) on a 7-point scale in which higher ratings indicate more positive perceptions. After adjusting for clinical experience, workload ratings were significantly higher in the bronchospasm scenario than in the normal/routine use (P = 0.046; 95% CI, 0.33-34.7) or power failure scenarios (P = 0.012; 95% CI, 5.24-37.9). Thirty-two specific usability issues were identified and grouped into five themes: device design and labeling, machine use during simulation scenarios, user-anticipated errors or hazards, curriculum issues, and overall impressions of the UAM®. CONCLUSIONS: The UAM® design addresses many of the key challenges facing anesthesia providers in resource-constrained settings. The simulation-based human factors evaluation described here successfully identified opportunities for continued refinement of the initial device design as well as issues to be addressed in future curricula and cognitive aides.

Medical Simulation as a Vital Adjunct to Identifying Clinical Life-Threatening Gaps in Austere Environments.

BACKGROUND: Maternal mortality and morbidity are major causes of death in low-resource countries, especially those in Sub-Saharan Africa. Healthcare workforce scarcities present in these locations result in poor perioperative care access and quality. These scarcities also limit the capacity for progressive development and enhancement of workforce training, and skills through continuing medical education. Newly available low-cost, in-situ simulation systems make it possible for a small cadre of trainers to use simulation to identify areas needing improvement and to rehearse best practice approaches, relevant to the context of target environments. METHODS: Nurse anesthetists were recruited throughout Sierra Leone to participate in simulation-based obstetric anesthesia scenarios at the country's national referral maternity hospital. All subjects participated in a detailed computer assisted training program to familiarize themselves with the Universal Anesthesia Machine (UAM). An expert panel rated the morbidity/mortality risk of pre-identified critical incidents within the scenario via the Delphi process. Participant responses to critical incidents were observed during these scenarios. Participants had an obstetric anesthesia pretest and post-test as well as debrief sessions focused on reviewing the significance of critical incident responses observed during the scenario. RESULTS: 21 nurse anesthetists, (20% of anesthesia providers nationally) participated. Median age was 41 years and median experience practicing anesthesia was 3.5 years. Most participants (57.1%) were female, two-thirds (66.7%) performed obstetrics anesthesia daily but 57.1% had no experience using the UAM. During the simulation, participants were observed and assessed on critical incident responses for case preparation with a median score of 7 out of 13 points, anesthesia management with a median score of 10 out of 20 points and rapid sequence intubation with a median score of 3 out of 10 points. CONCLUSION: This study identified substantial risks to patient care and provides evidence to support the feasibility and value of in-situ simulation-based performance assessment for identifying critical gaps in safe anesthesia care in the low-resource settings. Further investigations may validate the impact and sustainability of simulation based training on skills transfer and retention among anesthesia providers low resource environments.

Anesthesia Practice and Perioperative Outcomes at Two Tertiary Care Hospitals in Freetown, Sierra Leone.

BACKGROUND: Anesthesia in West Africa is associated with high mortality rates. Critical shortages of adequately trained personnel, unreliable electrical supply, and lack of basic monitoring equipment are a few of the unique challenges to surgical care in this region. This study aims to describe the anesthesia practice at 2 tertiary care hospitals in Sierra Leone. METHODS: We conducted an observational study of anesthesia care at Connaught Hospital and Princess Christian Maternity Hospital in Freetown, Sierra Leone. Twenty-five percent of the anesthesia workforce in Sierra Leone, resident at both hospitals, was observed from June 2012 to February 2013. Perioperative assessments, anesthetic techniques, and intraoperative clinical and environmental irregularities were noted and analyzed. The postoperative status of observed cases was ascertained for morbidity and mortality. RESULTS: Between the 2 hospitals, 754 anesthesia cases and 373 general anesthetics were observed. Ketamine was the predominant IV anesthetic used. Both hospitals experienced infrastructural and environmental constraints to the delivery of anesthesia care during the observation period. Vital sign monitoring was irregular and dependent on age and availability of monitors. Perioperative mortality during the course of the study was 11.9 deaths/1000 anesthetics. CONCLUSIONS: We identified gaps in the application of internationally recommended anesthesia practices at both hospitals, likely caused by lack of available resources. Mortality rates were similar to those in other resource-limited countries.

Engaging staff to improve quality and safety in an austere medical environment: a case-control study in two Sierra Leonean hospitals.

QUALITY PROBLEM OR ISSUE: Inadequate observance of basic processes in patient care such as patient monitoring and documentation practices are potential impediments to the timely diagnoses and management of patients. These gaps exist in low resource settings such as Sierra Leone and can be attributed to a myriad of factors such as workforce and technology deficiencies. INITIAL ASSESSMENT: In the study site, only 12.4% of four critical vital signs were documented in the pre-intervention period. CHOICE OF SOLUTION: Implement a failure mode and effects analysis (FMEA) to improve documentation of four patient vital signs: temperature, blood pressure, pulse rate and respiratory rate. IMPLEMENTATION: FMEA was implemented among a subpopulation of health workers who are involved in monitoring and documenting patient vital signs. Pre- and post-FMEA monitoring and documentation practice were compared with a control site. EVALUATION: Participants identified a four-step process to monitoring and documenting vital signs, three categories of failure modes and four potential solutions. Based on 2100 patient days of documentation compliance data from 147 patients between July and November 2012, staff members at the study site were 1.79 times more likely to document all four patient vital signs in the post-implementation period (95% CI [1.35, 2.38]). LESSONS LEARNED: FMEA is a feasible and effective strategy for improving quality and safety in an austere medical environment. Documentation compliance improved at the intervention facility. To evaluate the scalability and sustainability of this approach, programs targeting the development of these types of process improvement skills in local staff should be evaluated.

Failure mode and effects analysis applied to the maintenance and repair of anesthetic equipment in an austere medical environment.

OBJECTIVE: Medical technology designed for Western settings frequently does not function adequately or as intended when placed in an austere clinical environment because of issues such as the instability of the electrical grid, environmental conditions, access to replacement parts, level of provider training and general absence of biomedical engineering support. The purpose of this study was to demonstrate the feasibility of applying failure mode and effects analysis as part of an implementation strategy for medical devices in austere medical settings. DESIGN: Observational case-study. SETTING/PARTICIPANTS/INTERVENTION: We conducted failure mode and effects analysis sessions with 16 biomedical engineering technicians at two tertiary-care hospitals in Freetown, Sierra Leone. The sessions focused on maintenance and repair processes for the Universal Anaesthesia Machine. Participating biomedical engineers detailed local maintenance and repair processes and failure modes, including resource availability, communication challenges, use errors and physical access to the machine. MAIN OUTCOME MEASURE(S): Qualitative descriptive themes in barriers perceived and solutions generated by biomedical engineers. RESULTS: Solutions generated involved redesigned work processes to increase the efficiency of identifying machine malfunctions, clinician engagement strategies, a formal plan for acquiring spare parts and plans for improving access to the machine. Follow-up interviews indicated solutions generated were implemented and perceived to be effective. CONCLUSIONS: This study demonstrates the feasibility of using the failure mode and effects analysis approach to improve implementation of technology in austere medical environments.