Search

Summary: Background: The 7th National Audit Project of the Royal College of Anaesthetists studied peri‐operative cardiac arrest because of existing knowledge gaps in this important topic. This applies in particular to cardiology patients receiving anaesthetic care, because numbers, types and complexity of minimally invasive interventional procedures requiring planned and unplanned anaesthesia in the cardiac intervention suite is increasing. Methods: We analysed collected data to determine the epidemiology, clinical features, management and outcomes of peri‐operative cardiac arrest in adult patients receiving anaesthetic care for cardiology procedures. Results: There were 54 reports of peri‐operative cardiac arrest in adult patients receiving anaesthetic care for cardiology procedures, accounting for 54/881 (6.1%) of all reports to NAP7. The estimated incidence (95%CI) of cardiac arrests in this group was 1/450 or 0.22 (0.17–0.29)%. These patients were older than other adult patients in the NAP7 population, with a notably high proportion of patients of Asian ethnicity when compared with the remaining NAP7 cohort (9/54, 17% vs. 35/709, 5%). Rates of extracorporeal membrane oxygenation cardiopulmonary resuscitation were low (3/53, 6%). A common theme was that of logistical issues and teamworking, with reporters commenting on the difficulties of remote and/or unfamiliar locations and communication issues between specialties, on occasion resulting in poor teamworking and a lack of focus. The NAP7 panel review identified several other common themes which included: cardiogenic shock; late involvement of anaesthesia in the case; and transcatheter aortic valve implantation. Conclusion: Cardiology procedures requiring anaesthesia care account for < 1% of anaesthesia activity but generate 6% of all peri‐operative cardiac arrests. The incidence of cardiac arrest was disproportionately high in cardiological procedures requiring anaesthetic care. The nature of the cardiac arrest reports to NAP7 indicate that logistical and human factors in multidisciplinary teams in the cardiac intervention suite merit addressing to improve care. [ABSTRACT FROM AUTHOR]

Summary: Frailty increases peri‐operative risk, but details of its burden, clinical features and the risk of, and outcomes following, peri‐operative cardiac arrest are lacking. As a preplanned analysis of the 7th National Audit Project of the Royal College of Anaesthetists, we described the characteristics of older patients living with frailty undergoing anaesthesia and surgery, and those reported to the peri‐operative cardiac arrest case registry. In the activity survey, 1676 (26%) of 6466 patients aged > 65 y were reported as frail (Clinical Frailty Scale score ≥ 5). Increasing age and frailty were both associated with increasing comorbidities and the proportion of surgery undertaken as an emergency. Except in patients who were terminally ill (Clinical Frailty Scale score 9), increasing frailty was associated with an increased proportion of complex or major surgery. The rate of use of invasive arterial blood pressure monitoring was associated with frailty only until Clinical Frailty Scale score 5, and then plateaued or fell. Of 881 cardiac arrests reported to the 7th National Audit Project, 156 (18%) were in patients aged > 65 y and living with frailty, with an estimated incidence of 1 in 1204 (95%CI 1 in 1027–1412) and a mortality rate of 1 in 2020 (95%CI 1 in 1642–2488), approximately 2.6‐fold higher than in adults who were not frail. Hip fracture, emergency laparotomy, emergency vascular surgery and urological surgery were the most common surgical procedures in older patients living with frailty who had a cardiac arrest. We report a high burden of frailty within the surgical population, requiring complex, urgent surgery, and the extent of poorer outcomes of peri‐operative cardiac arrest compared with patients of the same age not living with frailty. [ABSTRACT FROM AUTHOR]

Summary: The 7th National Audit Project of the Royal College of Anaesthetists studied peri‐operative cardiac arrest in the UK, a topic of importance to patients, anaesthetists and surgeons. We report the results of the 12‐month registry phase, from 16 June 2021 to 15 June 2022, focusing on management and outcomes. Among 881 cases of peri‐operative cardiac arrest, the initial rhythm was non‐shockable in 723 (82%) cases, most commonly pulseless electrical activity. There were 665 (75%) patients who survived the initial event and 384 (52%) who survived to hospital discharge. A favourable functional outcome (based on modified Rankin Scale score) was reported for 249 (88%) survivors. Outcomes varied according to arrest rhythm. The highest rates of survival were seen for bradycardic cardiac arrests with 111 (86%) patients surviving the initial event and 77 (60%) patients surviving the hospital episode. The lowest survival rates were seen for patients with pulseless electrical activity, with 312 (68%) surviving the initial episode and 156 (34%) surviving to hospital discharge. Survival to hospital discharge was worse in patients at the extremes of age with 76 (40%) patients aged > 75 y and 9 (45%) neonates surviving. Hospital survival was also associated with surgical priority, with 175 (88%) elective patients and 176 (37%) non‐elective patients surviving to discharge. Outcomes varied with the cause of cardiac arrest, with lower initial survival rates for pulmonary embolism (5, 31%) and bone cement implantation syndrome (9, 45%), and hospital survival of < 25% for pulmonary embolism (0), septic shock (13, 24%) and significant hyperkalaemia (1, 20%). Overall care was rated good in 464 (53%) cases, and 18 (2%) cases had overall care rated as poor. Poor care elements were present in a further 245 (28%) cases. Care before cardiac arrest was the phase most frequently rated as poor (92, 11%) with elements of poor care identified in another 186 (21%) cases. These results describe the management and outcomes of peri‐operative cardiac arrest in UK practice for the first time. [ABSTRACT FROM AUTHOR]

Summary: The 7th National Audit Project of the Royal College of Anaesthetists studied peri‐operative cardiac arrest in the UK, a topic of importance to patients, anaesthetists and surgeons. Here we report the results of the 12‐month registry, from 16 June 2021 to 15 June 2022, focusing on epidemiology and clinical features. We reviewed 881 cases of peri‐operative cardiac arrest, giving an incidence of 3 in 10,000 anaesthetics (95%CI 3.0–3.5 per 10,000). Incidence varied with patient and surgical factors. Compared with denominator survey activity, patients with cardiac arrest: included more males (56% vs. 42%); were older (median (IQR) age 60.5 (40.5–80.5) vs. 50.5 (30.5–70.5) y), although the age distribution was bimodal, with infants and patients aged > 66 y overrepresented; and were notably more comorbid (73% ASA physical status 3–5 vs. 27% ASA physical status 1–2). The surgical case‐mix included more weekend (14% vs. 11%), out‐of‐hours (19% vs. 10%), non‐elective (65% vs. 30%) and major/complex cases (60% vs. 28%). Cardiac arrest was most prevalent in orthopaedic trauma (12%), lower gastrointestinal surgery (10%), cardiac surgery (9%), vascular surgery (8%) and interventional cardiology (6%). Specialities with the highest proportion of cases relative to denominator activity were: cardiac surgery (9% vs. 1%); cardiology (8% vs. 1%); and vascular surgery (8% vs. 2%). The most common causes of cardiac arrest were: major haemorrhage (17%); bradyarrhythmia (9%); and cardiac ischaemia (7%). Patient factors were judged a key cause of cardiac arrest in 82% of cases, anaesthesia in 40% and surgery in 35%. [ABSTRACT FROM AUTHOR]

Summary: Complications and critical incidents arising during anaesthesia due to patient, surgical or anaesthetic factors, may cause harm themselves or progress to more severe events, including cardiac arrest or death. As part of the 7th National Audit Project of the Royal College of Anaesthetists, we studied a prospective national cohort of unselected patients. Anaesthetists recorded anonymous details of all cases undertaken over 4 days at their site through an online survey. Of 416 hospital sites invited to participate, 352 (85%) completed the survey. Among 24,172 cases, 1922 discrete potentially serious complications were reported during 1337 (6%) cases. Obstetric cases had a high reported major haemorrhage rate and were excluded from further analysis. Of 20,996 non‐obstetric cases, 1705 complications were reported during 1150 (5%) cases. Circulatory events accounted for most complications (616, 36%), followed by airway (418, 25%), metabolic (264, 15%), breathing (259, 15%), and neurological (41, 2%) events. A single complication was reported in 851 (4%) cases, two complications in 166 (1%) cases and three or more complications in 133 (1%) cases. In non‐obstetric elective surgery, all complications were 'uncommon' (10–100 per 10,000 cases). Emergency (urgent and immediate priority) surgery accounted for 3454 (16%) of non‐obstetric cases but 714 (42%) of complications with severe hypotension, major haemorrhage, severe arrhythmias, septic shock, significant acidosis and electrolyte disturbances all being 'common' (100–1000 per 10,000 cases). Based on univariate analysis, complications were associated with: younger age; higher ASA physical status; male sex; increased frailty; urgency and extent of surgery; day of the week; and time of day. These data represent the rates of potentially serious complications during routine anaesthesia care and may be valuable for risk assessment and patient consent. [ABSTRACT FROM AUTHOR]

Summary: The Royal College of Anaesthetists' 7th National Audit Project baseline survey assessed knowledge, attitudes, practices and experiences of peri‐operative cardiac arrests among UK anaesthetists and Anaesthesia Associates. We received 10,746 responses, representing a 71% response rate. In‐date training in adult and paediatric advanced life support was reported by 9646 (90%) and 7125 (66%) anaesthetists, respectively. There were 8994 (84%) respondents who were confident in leading a peri‐operative cardiac arrest, with males more confident than females, but only 5985 (56%) were confident in leading a debrief and 7340 (68%) communicating with next of kin. In the previous two years, 4806 (46%) respondents had managed at least one peri‐operative cardiac arrest, of which 321 (7%) and 189 (4%) of these events involved a child or an obstetric patient, respectively. Respondents estimated the most common causes of peri‐operative cardiac arrest to be hypovolaemia, hypoxaemia and cardiac ischaemia, with haemorrhage coming fifth. However, the most common reported causes for the most recently attended peri‐operative cardiac arrest were haemorrhage; (927, 20%); anaphylaxis (474, 10%); and cardiac ischaemia (397, 9%). Operating lists or shifts were paused or stopped after 1330 (39%) cardiac arrests and 1693 (38%) respondents attended a debrief, with 'hot' debriefs most common. Informal wellbeing support was relatively common (2458, 56%) and formal support was uncommon (472, 11%). An impact on future care delivery was reported by 196 (4%) anaesthetists, most commonly a negative psychological impact. Management of a peri‐operative cardiac arrest during their career was reported by 8654 (85%) respondents. The overall impact on professional life was more often judged positive (2630, 30%) than negative (1961, 23%), but impact on personal life was more often negative. [ABSTRACT FROM AUTHOR]

Summary: We report the results of the Royal College of Anaesthetists' 7th National Audit Project organisational baseline survey sent to every NHS anaesthetic department in the UK to assess preparedness for treating peri‐operative cardiac arrest. We received 199 responses from 277 UK anaesthetic departments, representing a 72% response rate. Adult and paediatric anaesthetic care was provided by 188 (95%) and 165 (84%) hospitals, respectively. There was no paediatric intensive care unit on‐site in 144 (87%) hospitals caring for children, meaning transfer of critically ill children is required. Remote site anaesthesia is provided in 182 (92%) departments. There was a departmental resuscitation lead in 113 (58%) departments, wellbeing lead in 106 (54%) and departmental staff wellbeing policy in 81 (42%). A defibrillator was present in every operating theatre suite and in all paediatric anaesthesia locations in 193 (99%) and 149 (97%) departments, respectively. Advanced airway equipment was not available in: every theatre suite in 13 (7%) departments; all remote locations in 103 (57%) departments; and all paediatric anaesthesia locations in 23 (15%) departments. Anaesthetic rooms were the default location for induction of anaesthesia in adults and children in 148 (79%) and 121 (79%) departments, respectively. Annual updates in chest compressions and in defibrillation were available in 149 (76%) and 130 (67%) departments, respectively. Following a peri‐operative cardiac arrest, debriefing and peer support programmes were available in 154 (79%) and 57 (29%) departments, respectively. While it is likely many UK hospitals are very well prepared to treat anaesthetic emergencies including cardiac arrest, the survey suggests this is not universal. [ABSTRACT FROM AUTHOR]

Summary: Detailed contemporary knowledge of the characteristics of the surgical population, national anaesthetic workload, anaesthetic techniques and behaviours are essential to monitor productivity, inform policy and direct research themes. Every 3–4 years, the Royal College of Anaesthetists, as part of its National Audit Projects (NAP), performs a snapshot activity survey in all UK hospitals delivering anaesthesia, collecting patient‐level encounter data from all cases under the care of an anaesthetist. During November 2021, as part of NAP7, anaesthetists recorded details of all cases undertaken over 4 days at their site through an online survey capturing anonymous patient characteristics and anaesthetic details. Of 416 hospital sites invited to participate, 352 (85%) completed the activity survey. From these, 24,177 reports were returned, of which 24,172 (99%) were included in the final dataset. The work patterns by day of the week, time of day and surgical specialty were similar to previous NAP activity surveys. However, in non‐obstetric patients, between NAP5 (2013) and NAP7 (2021) activity surveys, the estimated median age of patients increased by 2.3 years from median (IQR) of 50.5 (28.4–69.1) to 52.8 (32.1–69.2) years. The median (IQR) BMI increased from 24.9 (21.5–29.5) to 26.7 (22.3–31.7) kg.m–2. The proportion of patients who scored as ASA physical status 1 decreased from 37% in NAP5 to 24% in NAP7. The use of total intravenous anaesthesia increased from 8% of general anaesthesia cases to 26% between NAP5 and NAP7. Some changes may reflect the impact of the COVID‐19 pandemic on the anaesthetic population, though patients with confirmed COVID‐19 accounted for only 149 (1%) cases. These data show a rising burden of age, obesity and comorbidity in patients requiring anaesthesia care, likely to impact UK peri‐operative services significantly. [ABSTRACT FROM AUTHOR]

Summary: Cardiac arrest in the peri‐operative period is rare but associated with significant morbidity and mortality. Current reporting systems do not capture many such events, so there is an incomplete understanding of incidence and outcomes. As peri‐operative cardiac arrest is rare, many hospitals may only see a small number of cases over long periods, and anaesthetists may not be involved in such cases for years. Therefore, a large‐scale prospective cohort is needed to gain a deep understanding of events leading up to cardiac arrest, management of the arrest itself and patient outcomes. Consequently, the Royal College of Anaesthetists chose peri‐operative cardiac arrest as the 7th National Audit Project topic. The study was open to all UK hospitals offering anaesthetic services and had a three‐part design. First, baseline surveys of all anaesthetic departments and anaesthetists in the UK, examining respondents' prior peri‐operative cardiac arrest experience, resuscitation training and local departmental preparedness. Second, an activity survey to record anonymised details of all anaesthetic activity in each site over 4 days, enabling national estimates of annual anaesthetic activity, complexity and complication rates. Third, a case registry of all instances of peri‐operative cardiac arrest in the UK, reported confidentially and anonymously, over 1 year starting 16 June 2021, followed by expert review using a structured process to minimise bias. The definition of peri‐operative cardiac arrest was the delivery of five or more chest compressions and/or defibrillation in a patient having a procedure under the care of an anaesthetist. The peri‐operative period began with the World Health Organization 'sign‐in' checklist or first hands‐on contact with the patient and ended either 24 h after the patient handover (e.g. to the recovery room or intensive care unit) or at discharge if this occured earlier than 24 h. These components described the epidemiology of peri‐operative cardiac arrest in the UK and provide a basis for developing guidelines and interventional studies. [ABSTRACT FROM AUTHOR]

Laser repair of dynamic random-access memories is commercially significant at the 1-Mbit density and larger. The window of acceptable laser parameters required to repair these parts typically decreases with each successive device generation because of increased variations in oxide thickness. A simple single-zone binary optic was developed to modify the beam profile from Gaussian to flattop. Experiments performed on actual dynamic random-access memory parts verified a large increase in the laser energy process window because of the shaped beam profile.

Objective: To evaluate a fully automated algorithm for the establishment of tight glycemic control in critically ill patients and to compare the results with different routine glucose management protocols of three intensive care units (ICUs) across Europe (Graz, Prague, and London).Research Design and Methods: Sixty patients undergoing cardiac surgery (age 67 +/- 9 years, BMI 27.7 +/- 4.9 kg/m2, 17 women) with postsurgery blood glucose levels >120 mg/dl (6.7 mmol/l) were investigated in three different ICUs (20 per center). Patients were randomized to either blood glucose management (target range 80-110 mg/dl [4.4-6.1 mmol/l]) by the fully automated model predictive control (MPC) algorithm (n = 30, 10 per center) or implemented routine glucose management protocols (n = 30, 10 per center). In all patients, arterial glucose was measured hourly to describe the glucose profile until the end of the ICU stay but for a maximum period of 48 h.Results: Compared with routine protocols, MPC treatment resulted in a significantly higher percentage of time within the target glycemic range (% median [min-max]: 52 [17-92] vs. 19 [0-71]) over 0-24 h (P < 0.01). Improved glycemic control with MPC treatment was confirmed in patients remaining in the ICU for 48 h (0-24 h: 50 [17-71] vs. 21 [4-67], P < 0.05, and 24-48 h: 65 [38-96] vs. 25 [8-79], P < 0.05, for MPC [n = 16] vs. routine protocol [n = 13], respectively). Two hypoglycemic events (<54 mg/dl [3.0 mmol/l]) were observed with routine protocol treatment. No hypoglycemic event occurred with MPC.Conclusions: The data suggest that the MPC algorithm is safe and effective in controlling glycemia in critically ill postsurgery patients. [ABSTRACT FROM AUTHOR]

The history of the investigations into interalveolar communications (pores of Kohn) shows that the question whether they exist and, if so, their nature has for approximately a century been contentious. The present electron microscopic study of the lungs of mice demonstrates that alveolar pores are normal structures, with edges composed of intact alveolar wall. A number of planes are demonstrated from which a fully compatible reconstruction is made. It is concluded that pores are round or oval structures frequently having at least one type II alveolar cell forming part of their boundary. It is further postulated that pores may be divided by a capillary column stretching across the space, resulting in two openings. A type II alveolar cell forming part of the pore wall may straddle the capillary column. Alveolar macrophages may be found lying free in the pore or lying astride a capillary column. When lying in a corner position type II cells may occupy the full wall thickness and face into three alveoli. [ABSTRACT FROM PUBLISHER]