Neurological outcome following out of hospital cardiac arrest: Evaluation of performance of existing risk prediction models in a UK cohort.

Introduction: Out of hospital cardiac arrest (OHCA) is a common problem. Rates of survival are low and a proportion of survivors are left with an unfavourable neurological outcome. Four models have been developed to predict risk of unfavourable outcome at the time of critical care admission - the Cardiac Arrest Hospital Prognosis (CAHP), MIRACLE2, Out of Hospital Cardiac Arrest (OHCA), and Targeted Temperature Management (TTM) models. This evaluation evaluates the performance of these four models in a United Kingdom population and provides comparison to performance of the Acute Physiology and Chronic Health Evaluation II (APACHE-II) score. Methods: A retrospective evaluation of the performance of the models was conducted over a 43-month period in 414 adult, non-pregnant patients presenting consecutively following non-traumatic OHCA to the five units in our regional critical care network. Scores were generated for each model for where patients had complete data (CAHP = 347, MIRACLE2 = 375, OHCA = 356, TTM = 385). Cerebral Performance Category (CPC) outcome was calculated for each patient at last documented follow up and an unfavourable outcome defined as CPC ⩾ 3. Performance for discrimination of unfavourable outcome was tested by generating receiver operating characteristic (ROC) curves for each model and comparing the area under the curve (AUC). Results: Best performance for discrimination of unfavourable outcome was demonstrated by the high risk group of the CAHP score with an AUC of 0.87 [95% CI 0.83-0.91], specificity of 97.1% [95% CI 93.8-100] and positive predictive value (PPV) of 96.3% [95% CI 92.2-100]. The high risk group of the MIRACLE2 model, which is significantly easier to calculate, had an AUC of 0.81 [95% CI 0.76-0.86], specificity of 92.3% [95% CI 87.2-97.4] and PPV of 95.2% [95% CI 91.9-98.4]. Conclusion: The CAHP, MIRACLE2, OHCA and TTM scores all perform comparably in a UK population to the original development and validation cohorts. All four scores outperform APACHE-II in a population of patients resuscitated from OHCA. CAHP and TTM perform best but are more complex to calculate than MIRACLE2, which displays inferior performance.

A critical care follow-up service evaluation: Acquired peripheral nerve injury after admission with COVID-19 respiratory disease.

Anticipated sequelae of critical care admission for COVID-19 disease remain unclear. Our Edinburgh-based critical care follow-up service identified patterns with nerve injury in 13 of 35 patients who attended following a critical care admission between 15/03/2020 and 25/12/2020. This included 7 cases of meralgia parasthetica, 1 brachial plexopathy, 2 common peroneal neuropathies and 3 ulnar neuropathies. All cases of upper limb neuropathy and foot drop occurred in patients in whom prone positioning was used, with meralgia parasthetica occurring additionally in patients who remained supine.

Laparoscopic Adrenalectomy for Conn's Syndrome is Beneficial to Patients and is Cost Effective in England.

PURPOSE: Adrenalectomy has the potential to cure or improve the control of hypertension in patients with primary hyperaldosteronism due to unilateral adrenal adenoma (Conn's syndrome). This study assesses the patients' perception of, and costs associated with, laparoscopic adrenalectomy for Conn's syndrome. MATERIALS AND METHODS: Clinical, radiological, operative, and pathological data were collected on patients undergoing adrenalectomy for Conn's syndrome over 8-years period in a UK tertiary referral center. RESULTS: Thirty-eight patients (17M:21F, age 34-79 yrs, median 54 yrs) operated between Jan2005-Sept2012 had lateralization based on CT scans (n = 30) and/or MRI scans (n = 18) and confirmed on selective adrenal venous sampling (n = 25). Laparoscopic adrenalectomy was performed in all patients, with two cases requiring conversion to open operation. Median operative time was 105 min (range: 27-315). Costs were estimated as £19k for preoperative investigations, £20k for in-hospital stay, £53k for operating theatre use and £29k for disposable surgical instruments, with average £3499/patient (national tariff for adrenalectomy in 2015/2016 £3624). Follow-up at a mean of 30 months postoperatively using a visual analogue scale and a standardized questionnaire showed significantly improved quality of life (QoL) post-operatively. Majority of patients (85%) reported taking none or fewer anti-hypertensive medications (median reduction of 2 antihypertensive drugs). All patients stated that they would definitely have the operation again in preference to anti-hypertensive medications and they would recommend the operation to friends/relatives. CONCLUSIONS: Laparoscopic adrenalectomy for Conn's syndrome has a positive impact on hypertension control, leads to improved QoL and its costs are covered in the NHS financial model.

Ischaemic strokes in patients with pulmonary arteriovenous malformations and hereditary hemorrhagic telangiectasia: associations with iron deficiency and platelets.

BACKGROUND: Pulmonary first pass filtration of particles marginally exceeding ∼7 µm (the size of a red blood cell) is used routinely in diagnostics, and allows cellular aggregates forming or entering the circulation in the preceding cardiac cycle to lodge safely in pulmonary capillaries/arterioles. Pulmonary arteriovenous malformations compromise capillary bed filtration, and are commonly associated with ischaemic stroke. Cohorts with CT-scan evident malformations associated with the highest contrast echocardiographic shunt grades are known to be at higher stroke risk. Our goal was to identify within this broad grouping, which patients were at higher risk of stroke. METHODOLOGY: 497 consecutive patients with CT-proven pulmonary arteriovenous malformations due to hereditary haemorrhagic telangiectasia were studied. Relationships with radiologically-confirmed clinical ischaemic stroke were examined using logistic regression, receiver operating characteristic analyses, and platelet studies. PRINCIPAL FINDINGS: Sixty-one individuals (12.3%) had acute, non-iatrogenic ischaemic clinical strokes at a median age of 52 (IQR 41-63) years. In crude and age-adjusted logistic regression, stroke risk was associated not with venous thromboemboli or conventional neurovascular risk factors, but with low serum iron (adjusted odds ratio 0.96 [95% confidence intervals 0.92, 1.00]), and more weakly with low oxygen saturations reflecting a larger right-to-left shunt (adjusted OR 0.96 [0.92, 1.01]). For the same pulmonary arteriovenous malformations, the stroke risk would approximately double with serum iron 6 µmol/L compared to mid-normal range (7-27 µmol/L). Platelet studies confirmed overlooked data that iron deficiency is associated with exuberant platelet aggregation to serotonin (5HT), correcting following iron treatment. By MANOVA, adjusting for participant and 5HT, iron or ferritin explained 14% of the variance in log-transformed aggregation-rate (p = 0.039/p = 0.021). SIGNIFICANCE: These data suggest that patients with compromised pulmonary capillary filtration due to pulmonary arteriovenous malformations are at increased risk of ischaemic stroke if they are iron deficient, and that mechanisms are likely to include enhanced aggregation of circulating platelets.

Low serum iron levels are associated with elevated plasma levels of coagulation factor VIII and pulmonary emboli/deep venous thromboses in replicate cohorts of patients with hereditary haemorrhagic telangiectasia.

BACKGROUND: Elevated plasma levels of coagulation factor VIII are a strong risk factor for pulmonary emboli and deep venous thromboses. OBJECTIVES: To identify reversible biomarkers associated with high factor VIII and assess potential significance in a specific at-risk population. PATIENTS/METHODS: 609 patients with hereditary haemorrhagic telangiectasia were recruited prospectively in two separate series at a single centre. Associations between log-transformed factor VIII measured 6 months from any known thrombosis/illness, and patient-specific variables including markers of inflammation and iron deficiency, were assessed in stepwise multiple regression analyses. Age-specific incidence rates of radiologically proven pulmonary emboli/deep venous thromboses were calculated, and logistic regression analyses performed. RESULTS: In each series, there was an inverse association between factor VIII and serum iron that persisted after adjustment for age, inflammation and/or von Willebrand factor. Iron response elements within untranslated regions of factor VIII transcripts provide potential mechanisms for the association. Low serum iron levels were also associated with venous thromboemboli (VTE): the age-adjusted OR of 0.91 (95% CI 0.86 to 0.97) per 1 µmol/litre increase in serum iron implied a 2.5-fold increase in VTE risk for a serum iron of 6 µmol/litre compared with the mid-normal range (17 µmol/litre). The association appeared to depend on factor VIII, as once adjusted for factor VIII, the association between VTE and iron was no longer evident. CONCLUSIONS: In this population, low serum iron levels attributed to inadequate replacement of haemorrhagic iron losses are associated with elevated plasma levels of coagulation factor VIII and venous thromboembolic risk. Potential implications for other clinical populations are discussed.