The reliability of the College of Intensive Care Medicine of Australia and New Zealand "Hot Case" examination.

BACKGROUND: High stakes examinations used to credential trainees for independent specialist practice should be evaluated periodically to ensure defensible decisions are made. This study aims to quantify the College of Intensive Care Medicine of Australia and New Zealand (CICM) Hot Case reliability coefficient and evaluate contributions to variance from candidates, cases and examiners. METHODS: This retrospective, de-identified analysis of CICM examination data used descriptive statistics and generalisability theory to evaluate the reliability of the Hot Case examination component. Decision studies were used to project generalisability coefficients for alternate examination designs. RESULTS: Examination results from 2019 to 2022 included 592 Hot Cases, totalling 1184 individual examiner scores. The mean examiner Hot Case score was 5.17 (standard deviation 1.65). The correlation between candidates' two Hot Case scores was low (0.30). The overall reliability coefficient for the Hot Case component consisting of two cases observed by two separate pairs of examiners was 0.42. Sources of variance included candidate proficiency (25%), case difficulty and case specificity (63.4%), examiner stringency (3.5%) and other error (8.2%). To achieve a reliability coefficient of > 0.8 a candidate would need to perform 11 Hot Cases observed by two examiners. CONCLUSION: The reliability coefficient for the Hot Case component of the CICM second part examination is below the generally accepted value for a high stakes examination. Modifications to case selection and introduction of a clear scoring rubric to mitigate the effects of variation in case difficulty may be helpful. Increasing the number of cases and overall assessment time appears to be the best way to increase the overall reliability. Further research is required to assess the combined reliability of the Hot Case and viva components.

The Hematological Effects of Extracorporeal Membrane Oxygenator Exchange.

Membrane oxygenator failure during venovenous (V-V) extracorporeal membrane oxygenation (ECMO) can lead to life-threatening hypoxia, high replacement costs, and may be associated with a hyperfibrinolytic state and bleeding. The current understanding of the underlying mechanisms that drive this is limited. The primary aim of this study therefore is to investigate the hematological changes that occur before and after membrane oxygenator and circuit exchanges (ECMO circuit exchange) in patients with severe respiratory failure managed on V-V ECMO. We analyzed 100 consecutive V-V ECMO patients using linear mixed-effects modeling to evaluate hematological markers in the 72 hours before and 72 hours after ECMO circuit exchange. A total of 44 ECMO circuit exchanges occurred in 31 of 100 patients. The greatest change from baseline to peak were seen in plasma-free hemoglobin (42-fold increase p < 0.01) and the D-dimer:fibrinogen ratio (1.6-fold increase p = 0.03). Bilirubin, carboxyhemoglobin, D-dimer, fibrinogen, and platelets also showed statistically significant changes ( p < 0.01), whereas lactate dehydrogenase did not ( p = 0.93). Progressively deranged hematological markers normalize more than 72 hours after ECMO circuit exchange, with an associated reduction in membrane oxygenator resistance. This supports the biologic plausibility that ECMO circuit exchange may prevent further complications such as hyperfibrinolysis, membrane failure, and clinical bleeding.

Too hot to handle? Assessing the validity and reliability of the College of Intensive Care Medicine "Hot Case" examination.

The College of Intensive Care Medicine of Australia and New Zealand is responsible for credentialling trainees for specialist practice in intensive care medicine for the safety of patients and the community. This involves defining trainees' performance standards and testing trainees against those standards to ensure safe practice. The second part examination performed towards the end of the training program is a high-stakes assessment. The two clinical "Hot Cases" performed in the examination have a low pass rate, with most candidates failing at least one of the cases. There is increasing expectation for medical specialist training colleges to provide fair and transparent assessment processes to enable defensible decisions regarding trainee progression. Examinations are a surrogate marker of clinical performance with advantages, disadvantages and inevitable compromises. This article evaluates the Hot Case examination using Kane's validity framework and van der Vleuten's utility equation, and identifies issues with validity and reliability which could be managed through an ongoing improvement process.

Very old patients urgently referred to the intensive care unit: long-term outcomes for admitted and declined patients.

BACKGROUND: Outcomes for very old patients (≥ 80 years) referred but not admitted to an intensive care unit have not been described in Australia and New Zealand. OBJECTIVE: To ascertain long-term (12-month) outcomes for very old patients urgently referred for ICU support at a tertiary referral hospital. DESIGN, SETTING AND PATIENTS: A retrospective, medical record review of 1240 very old patients (≥ 80 years) who were urgently referred to an Australian, 31-bed ICU over a 40-month period from March 2011 to August 2014. Referrals were divided into those who were "too well" for the ICU, admitted to the ICU, and "too sick" for the ICU. Data and main outcome measures: Data were extracted from hospital records, the ICU patient database and the Australian Institute of Health and Welfare National Death Index, and our main outcome measures were health status and destination at hospital discharge, and 12-month mortality rates. RESULTS: Urgent admissions of very old patients accounted for 6.9% of total ICU admissions (443/6415). The hospital mortality rate was 16.0% (93/583) for patients who were too well, 32.1% (142/443) for those admitted to the ICU, and 69.2% (148/214) for those too sick (P ≥ 0.001). Mortality rates 12 months after referral were 40.8% (238/583), 46.0% (204/443) and 88.3% (189/214), respectively (P ≥ 0.001). CONCLUSION: Very old patients considered too well for the ICU have a significantly lower hospital mortality rate than those admitted to the ICU after urgent referral. However, 12 months after referral, patients considered too well for ICU admission have a mortality rate approaching that of very old patients admitted to the ICU. Over half of very old patients urgently referred to the ICU die within 12 months.

Management of Cerebellar Tonsillar Herniation following Lumbar Puncture in Idiopathic Intracranial Hypertension.

Lumbar puncture is performed routinely for diagnostic and therapeutic purposes in idiopathic intracranial hypertension, despite lumbar puncture being classically contraindicated in the setting of raised intracranial pressure. We report the case of a 30-year-old female with known idiopathic intracranial hypertension who had cerebellar tonsillar herniation following therapeutic lumbar puncture. Management followed guidelines regarding treatment of traumatic intracranial hypertension, including rescue decompressive craniectomy. We hypothesize that the changes in brain compliance that are thought to occur in the setting of idiopathic intracranial hypertension are protective against further neuronal injury due to axonal stretch following decompressive craniectomy.

Comparison of asymmetry in cerebral blood flow between brain hemispheres using digital subtraction angiography.

BACKGROUND AND PURPOSE: Recently, endovascular techniques have gained significant therapeutic potential for both treatment and prevention of stroke. Cerebral angiography, which is an essential component of these procedures, has been used to provide morphological information regarding condition of blood vessels. In this study, we propose to determine the possibility of acquiring information regarding cerebral blood flow (CBF) in addition to morphologic information from data routinely available during angiography. METHODS: Digital subtraction angiography sequences were obtained for eight patients having occlusive disease in internal carotid artery (ICA) territories. Two regions-of-interest (ROIs) corresponding to the two brain hemispheres on AP view were delineated. For each image, the average pixel value within each ROI was calculated and used to generate time-density curves. Indices obtained from each curve were compared with each other and with the results obtained from the single photon emission computed tomography (SPECT) studies performed a pre- or postangiography procedure. RESULTS: Comparison between ICA stenosis and cerebral perfusion measurements revealed that cerebral perfusion deficit can be independent of arterial occlusive disease. The indices obtained from the time-density curves exhibit a correlating trend with the results from SPECT studies. However, lack of sufficient sample data prevented any meaningful statistical analysis to be conducted. CONCLUSIONS: We have developed a technique for utilizing the angiographic data for the important task of routinely and easily measuring CBF. Availability of CBF measurements during cerebral angiography may favorably impact upon the appropriate use of endovascular procedures and potentially contribute to the reduction of morbidity and mortality associated with stroke.