Haemodynamic changes during prone versus supine position in patients with COVID-19 acute respiratory distress syndrome.

BACKGROUND: Prone positioning improves oxygenation in patients with acute respiratory distress syndrome (ARDS) secondary to COVID-19. However, its haemodynamic effects are poorly understood. OBJECTIVES: The objective of this study was to investigate the acute haemodynamic changes associated with prone position in mechanically ventilated patients with COVID-19 ARDS. The primary objective was to describe changes in cardiac index with prone position. The secondary objectives were to describe changes in mean arterial pressure, FiO2, PaO2/FiO2 ratio, and oxygen delivery (DO2) with prone position. METHODS: We performed this cohort-embedded study in an Australian intensive care unit, between September and November 2021. We included adult patients with severe COVID-19 ARDS, requiring mechanical ventilation and prone positioning for respiratory failure. We placed patients in the prone position for 16 h per session. Using pulse contour technology, we collected haemodynamic data every 5 min for 2 h in the supine position and for 2 h in the prone position consecutively. RESULTS: We studied 18 patients. Cardiac index, stroke volume index, and mean arterial pressure increased significantly in the prone position compared to supine position. The mean cardiac index was higher in the prone group than in the supine group by 0.44 L/min/m2 (95% confidence interval, 0.24 to 0.63) (P < 0.001). FiO2 requirement decreased significantly in the prone position (P < 0.001), with a significant increase in PaO2/FiO2 ratio (P < 0.001). DO2 also increased significantly in the prone position, from a median DO2 of 597 mls O2/min (interquartile range, 504 to 931) in the supine position to 743 mls O2/min (interquartile range, 604 to 1075) in the prone position (P < 0.001). CONCLUSION: Prone position increased the cardiac index, mean arterial pressure, and DO2 in invasively ventilated patients with COVID-19 ARDS. These changes may contribute to improved tissue oxygenation and improved outcomes observed in trials of prone positioning.

Feasibility of pulse oximetry after water immersion.

OBJECTIVE: This study aimed to determine if pulse oximetry could reliably be used after immersion in water, and if so, which of the finger, earlobe or nose most reliably produced a functional waveform. METHOD: Pulse oximetry data was recorded from the ear, nose and finger before and after 30 min of immersion in water. The primary outcome was the ability to measure pulse oximetry at any of the sites. RESULTS: A total of 119 participants were enrolled (with a median age of 16 years, 55% male). A useful pulse oximetry waveform was obtained after immersion from at least one of the measurement sites in 118 (99.2%) participants. Waveforms were usable after immersion in 96% of participants at the nostril, compared to 92% at the finger, and 41% at the ear lobe. The likelihood of success at the ear was significantly lower than either the finger or the nose (41% vs 92% and 96% respectively, p < 0.0001 for both comparisons). The finger and nostril were similar. Oxygen saturations were not significantly different after immersion at the nostril (100% vs 100%, p = 0.537) and finger (100% vs 100%, p = 0.032) sites but were different at the ear (100% vs 96%, p < 0.0001). CONCLUSION: This study demonstrates that pulse oximetry is feasible and reliable in a large cohort of participants who have been immersed in water for 30 min. The results support the nostril as the most reliable location. Only pulse oximeters registered for clinical use should be employed for patient care.

Venous thromboembolism in critically ill COVID-19 patients receiving prophylactic or therapeutic anticoagulation: a systematic review and meta-analysis.

Many aspects of care such as management of hypercoagulable state in COVID-19 patients, especially those admitted to intensive care units is challenging in the rapidly evolving pandemic of novel coronavirus disease 2019 (COVID-19). We seek to systematically review the available evidence regarding the anticoagulation approach to prevent venous thromboembolism (VTE) among COVID-19 patients admitted to intensive care units. Electronic databases were searched for studies reporting venous thromboembolic events in patients admitted to the intensive care unit receiving any type of anticoagulation (prophylactic or therapeutic). The pooled prevalence (and 95% confidence interval [CI]) of VTE among patients receiving anticoagulant were calculated using the random-effects model. Subgroup pooled analyses were performed with studies reported prophylactic anticoagulation alone and with studies reported mixed prophylactic and therapeutic anticoagulation. We included twelve studies (8 Europe; 2 UK; 1 each from the US and China) in our systematic review and meta-analysis. All studies utilized LMWH or unfractionated heparin as their pharmacologic thromboprophylaxis, either prophylactic doses or therapeutic doses. Seven studies reported on the proportion of patients with the previous history of VTE (range 0-10%). The pooled prevalence of VTE among ICU patients receiving prophylactic or therapeutic anticoagulation across all studies was 31% (95% CI 20-43%). Subgroup pooled analysis limited to studies reported prophylactic anticoagulation alone and mixed (therapeutic and prophylactic anticoagulation) reported pooled prevalences of VTE of 38% (95% CI 10-70%) and 27% (95% CI 17-40%) respectively. With a high prevalence of thromboprophylaxis failure among COVID-19 patients admitted to intensive care units, individualised rather than protocolised VTE thromboprophylaxis would appear prudent at interim.

Conflicts of interest in the context of end of life care for potential organ donors in Australia.

End-of-life (EOL) care has become an integral part of intensive care medicine and includes the exploration of possibilities for deceased organ and tissue donation. Donation physicians are specialist doctors with expertise in EOL processes encompassing organ and tissue donation, who contribute significantly to improvements in organ and tissue donation services in many countries around the world. Donation physicians are usually also intensive care physicians, and thus they may be faced with the dual obligation of caring for dying patients and their families in the intensive care unit (ICU), whilst at the same time ensuring organ and tissue donation is considered according to best practice. This dual obligation poses specific ethical challenges that need to be carefully understood by clinicians, institutions and health care networks. These obligations are complementary and provide a unique skillset to care for dying patients and their families in the ICU. In this paper we review current controversies around EOL care in the ICU, including the use of palliative analgesia and sedation specifically with regards to withdrawal of cardiorespiratory support, the usefulness of the so-called doctrine of double effect to guide ethical decision-making, and the management of potential or perceived conflicts of interest in the context of dual professional roles.

The impact of organ donation specialists on consent rate in challenging organ donation conversations.

Background: Consent rates for organ donation conversations (ODCs) vary. We hypothesised that a simple grading system could identify challenging ODCs. We further hypothesised that challenging ODCs would have higher consent rates when conducted by ODC specialists. Objectives: We aimed to study the utility of a grading system for ODCs and test the hypothesis that any training effect would be associated with improved consent rates in ODCs graded as most challenging. Methods: We stratified 2017 Australian DonateLife Audit aggregate consent and donation discussion data into four ODC grades based on Australian Organ Donor Register (AODR) status and person first raising the topic of organ donation. Grade I: "yes" present on AODR and family-raised organ donation; Grade II: "yes" present on AODR, and clinician-raised organ donation; Grade III: no registration on AODR but family-raised organ donation; and Grade IV: no registration on AODR, and clinician-raised organ donation. Results: Grade I ODCs were uncommon 7.7% (109/1420), with a consent rate of 95.4% (104/109). Grade IV ODCs were frequent (60.4%, 857/1420), with a consent rate of 41.4% (355/857). However, in Grade IV ODCs, organ donation specialist consent rate was 53.5% (189/353), significantly greater than for other trained staff at 33.1% (88/266) (P < 0.005; odds ratio [OR], 2.33; 95% CI, 1.68-3.24) or untrained requestors at 32.8% (78/238; P < 0.005; OR, 2.36; 95% CI. 1.68-3.33). Conclusion: The likelihood of consent can be predicted using readily available variables. This allows prospective identification of Grade IV ODCs, which carry low but potentially modifiable likelihood of consent. Involving donation specialists was associated with more consents for organ donation when applied retrospectively to Australian audit data.

In-hospital cardiac arrest epidemiology in a mature rapid response system.

An audit examined the epidemiology of in-hospital cardiac arrests 5 years after a rapid response system was introduced, exploring the frequency of arrests in monitored and unmonitored areas. Details of the initial cardiac rhythm and what proportion of events were preceded by a medical emergency team call were also assessed.

Competence in the use of supraglottic airways by Australian surf lifesavers for cardiac arrest ventilation in a manikin.

OBJECTIVES: Lifesavers in Australia are taught to use pocket mask (PM) rescue breathing and bag valve mask (BVM) ventilation, despite evidence that first responders might struggle with these devices. Novices have successfully used the Laryngeal Mask Airway (LMA) Supreme and iGel devices previously, but there has been no previous comparison of the ability to train lifesavers to use the supraglottic airways compared to standard techniques for cardiac arrest ventilation. METHODS: The study is a prospective educational intervention whereby 113 lifesavers were trained to use the LMA and iGel supraglottic airways. Comparisons were made to standard devices on plastic manikins. Successful ventilation was defined as achieving visible chest rise. RESULTS: The median time to first effective ventilation was similar between the PM (16 s, 95% confidence interval 16-17 s), BVM (17 s, 16-17 s) and iGel devices (18 s, 16-20 s), but longer for the LMA (36 s, 33-38 s). The iGel frequently failed to achieve ventilation (10%) compared with the PM (1%, P < 0.01) and LMA (3%, P < 0.01) but was not worse than the BVM (3%, P < 0.57). Hands-off time was similar between the BVM, LMA and iGel (10 s for each device), but worse for the PM (13 s, P = 0.001). CONCLUSION: Lifesavers using the PM and BVM perform ventilation for cardiopulmonary resuscitation well. There appears to be a limited role for supraglottic airway devices because of limitations in terms of time to first effective ventilation and reliability. Clinical validation of manikin data with live resuscitation performance is required.

Participant perceptions of a rapid response team training course.

BACKGROUND: Rapid response team (RRT) responders would benefit from training, to ensure competent and efficient management of the deteriorating patient. DESIGN, SETTING AND PARTICIPANTS: We obtained delegate feedback on a pilot training course for RRTs, commissioned by the Australian and New Zealand Intensive Care Society (ANZICS), at the second ANZICS: The Deteriorating Patient Conference. METHODS: We surveyed participants on their perceptions of the course overall, and their perceptions of sessions containing presentations and videotaped and live demonstrations of simulated scenarios of patients whose conditions were deteriorating. RESULTS: The survey response rate was 64% (96 of 150 potential attendees). Responses were positive, with 79.8% of responses (912/1143) agreeing that the participants had learnt something new, that the course would increase their confidence and competence during RRT calls, and that it had assisted them as an educator. The course was well received overall, with the interactive and live demonstration components of the course garnering positive feedback in the comments section of surveys. CONCLUSIONS: There was unanimous agreement by participants for further development of a formalised RRT training course for responding to the deteriorating patient. Participants who were RRT educators also supported the development of an RRT train-the-trainer course.

Tasks completed by nursing members of a teaching hospital Medical Emergency Team.

OBJECTIVES: To assess tasks completed by intensive care medical emergency team nurses. RESEARCH DESIGN: Prospective observational study. SETTING: Australian teaching hospital. MAIN OUTCOME MEASURES: Nursing-related technical and non-technical tasks and level of self-reported confidence and competence. RESULTS: Amongst 400 calls, triggers and nursing tasks were captured in 93.5% and 77.3% of cases, respectively. The median patient age was 73 years. The four most common triggers were hypotension (22.0%), tachycardia (21.1%), low SpO2 (17.4%), and altered conscious state (10.1%). Non-technical skills included investigation review (33.7%), history acquisition (18.4%), contribution to the management plan (40.5%) and explanation to bedside nurses (78.3%), doctors (13.6%), allied health (3.9%) or patient/relative (39.5%). Technical tasks included examining the circulation (32%), conscious state (29.4%), and chest (26.5%). Additional tasks included adjusting oxygen (23.9%), humidification (8.4%), non-invasive ventilation (6.5%), performing an ECG (22%), and administrating fluid as a bolus (17.5%) or maintenance (16, 5.2%), or medication as a statim dose (16.8%) or infusion (5.2%). Self-reported competence and confidence appeared to be high overall amongst our MET nurses. CONCLUSION: Our findings provide important information on the tasks completed by Medical Emergency Team nurses and will guide future training.

Zebra in the intensive care unit: a metacognitive reflection on misdiagnosis.

Misdiagnosis of the cause of illness in critically ill patients is common, and a major cause of morbidity and mortality. We reflect upon a misdiagnosis that occurred in the intensive care unit of a metropolitan teaching hospital, and highlight the susceptibility of medical decision making to error. We examine recent advances in cognitive theory and how these apply to diagnosis. We discuss the vulnerability of such processes and - with particular reference to our case - why even knowledgeable and diligent clinicians are prone to misdiagnose. Finally, we review potential solutions, both educational and systemic, that may guard against the inevitable failings of the human mind, especially in a busy modern intensive care setting.

Crisis resource management, simulation training and the medical emergency team.

Recently there has been increased focus on improved detection and management of deteriorating patients in Australian hospitals. Since the introduction of the medical emergency team (MET) model there has been an increased role for intensive care unit staff in responding to deterioration of patients in hospital wards. Review and management of MET patients differs from the traditional model of ward patient review, as ICU staff may not know the patient. Furthermore, assessment and intervention is often time-critical and must occur simultaneously. Finally, about 10% of MET patients require intensive care-level interventions to be commenced on the ward, and this requires participation of non-ICU-trained ward staff. • To date, the interventions performed by MET staff and approaches to training responders have been relatively under investigated, particularly in the Australian and New Zealand context. In this article we briefly review the principles of the MET and contend that activation of the MET by ward staff represents a response to a medical crisis. We then outline why MET intervention differs from traditional ward-based doctor-patient encounters, and emphasise the importance of non-technical skills during the MET response. Finally, we suggest ways in which the skills required for crisis resource management within the MET can be taught to ICU staff, and the potential benefits, barriers and difficulties associated with the delivery of such training in New Zealand and Australia.