Anaesthesia and Intensive Care最新文献

Microcirculatory failure is recognised as a critical pathophysiological factor in the development of multi-organ failure in critically ill patients. However, traditional resuscitative efforts have focused on macrohaemodynamic variables such as blood pressure and cardiac output. These parameters may be insensitive for detecting changes in tissue perfusion when haemodynamic coherence is disturbed in states of shock. Several clinical studies using direct visualisation of the microcirculation have revealed that microcirculatory abnormalities can persist despite optimised global haemodynamic parameters. These abnormalities are independently associated with increased mortality. As the goal of resuscitation is to restore tissue perfusion, and the microcirculation closely reflects perfusion at the tissue level, interest in the microcirculation has grown over the years. Technological advances now allow direct observation and measurement of the microcirculation. This narrative review explores the current understanding of the microcirculation and its role in critical illness, with an overview of microcirculatory monitoring and its utility in clinical decision making.

Background: Dyskalaemias have been reported as an independent prognostic factor for adverse outcomes based on plasma potassium levels upon intensive care unit (ICU) admission or mean potassium levels across ICU stay, but the granular effects of discrete episodes of dyskalaemia have not been extensively studied.

Methods: This retrospective observational cohort study included all adult patients admitted to ICUs in public hospitals in Hong Kong between January 2010 and June 2023. Discrete episodes of dyskalaemia were defined if plasma potassium measurements were beyond the reference range of 3.5-5 mmol/l. Patients were classified into four groups based on the potassium levels throughout their ICU stay (normokalaemic, hyperkalaemic, hypokalaemic and mixed dyskalaemic). Patients with prolonged ICU length of stay beyond 14 days were excluded. The main study outcomes were ICU mortality and the incidence of arrhythmias, which was defined based on a pharmacological surrogate of requiring amiodarone between the onset of the dyskalaemic episode and ICU discharge.

Results: A total of 167,449 patients were included. A total of 60,953 (36.4%) patients remained normokalaemic. There were 21,820 (13.0%), 79,312 (47.4%) and 5364 (3.2%) patients in the hyperkalaemic, hypokalaemic and mixed dyskalaemic groups respectively. Dyskalaemia was significantly associated with increased ICU mortality (hyperkalaemia: adjusted odds ratio (aOR) 1.95, 95% confidence interval (CI) 1.79 to 2.12, P < 0.0001 vs hypokalaemia: aOR 1.83, 95% CI 1.70 to 1.96, P < 0.0001 vs mixed dyskalaemia: aOR 2·87, 95% CI 2.57 to 3.20, P < 0.0001). The same adverse effects of dyskalaemia were also observed in incidence of arrhythmias.

Conclusions: Having dyskalaemic episodes during the ICU stay was significantly associated with increased odds of ICU mortality and arrhythmias.

Desflurane is a potent and expensive greenhouse gas. Reducing its use is a global priority. This anaesthetist-led quality improvement project involved educational, motivational and system-change initiatives implemented in the anaesthesia department of Bankstown-Lidcombe Hospital (BLH) (September 2021-March 2024), with the aim of reducing desflurane consumption. A quasi-experimental interrupted time series design with control site was employed to estimate changes in usage, greenhouse gas emissions and financial cost of anaesthetic agents per 100 surgeries. Prior to intervention, use of desflurane at BLH was stable. During and after intervention, a significant downward trend in desflurane use was observed, reducing by an average of 0.1 units (1 unit = 1 bottle) per month per 100 surgeries from September 2021 onwards (95% confidence interval (CI) -0.21 to -0.01, P = 0.035). The intervention, while not directly targeting sevoflurane use, was similarly associated with a downward trend in sevoflurane usage of an average of 0.5 units per month per 100 surgeries from September 2021 onwards (95% CI -189.74 kg to -10.43 kg, P = 0.004). No significant changes in use of desflurane or sevoflurane were observed at the control site, although use of both agents declined slightly over the study period. Estimated CO₂ equivalent (CO₂e) emissions were reduced by an average of 124.7 kg per month per 100 surgeries from September 2021 onwards (95% CI -223.3 kg to -26.1 kg, P = 0.018). Average monthly cost per 100 surgeries at BLH reduced by AU$100.34 per month (95% CI -AU$162.58 to -AU$38.10, P = 0.003). There were no changes in CO₂e emissions or costs at the control site. A clinician-led intervention highlights the importance of creating opportunity and motivation for change amongst staff as well as ongoing education, advocacy and engagement with department and executive to achieve positive environmental and financial outcomes.

To analyse characteristics of patients eligible for organ donation in New Zealand (NZ) Intensive Care Units (ICUs) and identify potentially modifiable factors that may benefit donation conversations and their outcomes. Design: A retrospective analysis of eligible patient data collected by Organ Donation New Zealand (ODNZ). Twenty-three adult ICUs in NZ from January 1, 2018, to December 31, 2021. Participants: Adult ICU patients eligible for organ donation via neurological determination of death (DNDD) or circulatory determination of death (DCDD). Patient and ICU characteristics, preparations for donation conversations, donation decisions, and reasons for non-approaches or declines were analysed. Descriptive statistics and binary logistic regression evaluated factors and outcomes. A total of 1,267 cases were analysed (DNDD = 687, DCDD = 580). Donation conversations occurred in 46.9% of cases, with 51.3% resulting in consent. Patients' demographics and admission trends were similar to international reports. Male gender (p = 0.016) and ICU length of stay (p = 0.003) were associated with increased DCDD consent likelihood. Conditions such as encephalopathy (p = 0.012), and cardiovascular disease (p < 0.001) were associated with reduced donation conversation likelihood. Families of Māori patients were associated with reduced donation conversation likelihood (p = 0.002) and families of Māori (p < 0.001), Pasifika (p < 0.001), and Asian patients (p = 0.004) were associated with reduced consent likelihood. Early consultation with ODNZ and timely brain death confirmation positively impacted donation conversations and consent rates. Although not always practised, early ODNZ consultation and timely brain death confirmation were modifiable factors positively associated with conversations being approached and consent. Research exploring ICU staff and families' perspectives may improve understanding of influencing factors.

A 68-year-old man developed acute hypoxaemic respiratory failure after coronary bypass surgery and was started on non-invasive positive pressure ventilation. He experienced difficulty in exhaling, with expiratory flow flattening noted early in exhalation, despite the absence of the typical late pressure spike of delayed cycling. When the back-up rate was increased, mechanical inspiratory time decreased, the flow flattening disappeared, and his symptoms improved. This case suggests that early expiratory flow flattening may serve as an alternative sign of delayed cycling in non-invasively ventilated patients, reflecting overlap between mechanical insufflation and patient exhalation.

Postoperative complications increase morbidity and mortality. With an ever-increasing number of older and more frail patients requiring surgery, the demand for effective postoperative care is escalating. Currently, there is a notable disparity between postoperative ward-based care and the care provided in high dependency units (HDUs) and intensive care units (ICUs). This gap exposes intermediate-risk patients, with limited access to HDU/ICU facilities, to an increased risk of postoperative morbidity and mortality and has significant health economic implications. Mounting evidence supports preventive approaches, including the use of specialised, anaesthesia-led postoperative care delivered in enhanced care units (ECUs) which can bridge this gap effectively. Anaesthetists have a critical role in delivering enhanced perioperative care and are ideally positioned to lead this transformative approach. Current traditional ward-based approaches identify patient deterioration after it has occurred, exposing patients to avoidable hypotension and hypoxia and potentially non-specific treatment modalities such as intravenous fluid therapy for hypotension and low-flow nasal oxygen for hypoxia. Strategies for reducing early postoperative morbidity and mortality following surgery must focus on implementing policies which enhance perioperative care systems tailored to the unique pathophysiology of the postoperative period. Appropriate effector responses ideally would treat these perturbations before they occur or rapidly after identification using tailored therapeutic strategies specific to an individual patient's physiology. In this commentary, we highlight key aspects of postoperative pathophysiology that support the call for increasing access to appropriate postoperative care facilities, and offer ECUs as one scalable solution.

Critical care patients require continuous monitoring of vital signs and test results, yet efficiently collecting and using this data poses challenges in the intensive care unit (ICU). Usability limitations in electronic health records (EHRs) within critical care settings can delay access to essential information, potentially jeopardising patient safety. To address these issues, we developed a bedside display system that provides ICU staff with real-time, accurate access to critical data. Our system extracts and reorganises key ICU data from the existing EHR, thus avoiding costly and time-consuming upgrades. By automatically updating information such as laboratory results, blood gas analysis, lactate levels, ratio of partial pressure of arterial oxygen to fractional inspired oxygen, fluid balance and body temperature in real-time, the display allows rapid access to essential information for managing critically ill patients without the need for personal computer-based EHR logins. Post-implementation surveys with physicians, nurses and clinical engineers showed predominantly positive responses, recognising improvements in workflow and care quality. Survey results also highlighted the need for customising the display format to meet the unique requirements of each professional role, thereby maximising the system's effectiveness in critical care. This bedside display system offers four key benefits. It enhances data reliability during multidisciplinary rounds, enables physicians with busy schedules to access critical information efficiently, helps nurses detect changes in patient status early and allows a complete transition from paper-based to digital data collection. This approach offers a fresh perspective and has the potential to encourage further research into optimal information presentation methods in critical care settings.