EPidemiology Of Cardiogenic sHock in Scotland (EPOCHS): A multicentre, prospective observational study of the prevalence, management and outcomes of cardiogenic shock in Scotland.

Background: Despite high rates of cardiovascular disease in Scotland, the prevalence and outcomes of patients with cardiogenic shock are unknown. Methods: We undertook a prospective observational cohort study of consecutive patients with cardiogenic shock admitted to the intensive care unit (ICU) or coronary care unit at 13 hospitals in Scotland for a 6-month period. Denominator data from the Scottish Intensive Care Society Audit Group were used to estimate ICU prevalence; data for coronary care units were unavailable. We undertook multivariable logistic regression to identify factors associated with in-hospital mortality. Results: In total, 247 patients with cardiogenic shock were included. After exclusion of coronary care unit admissions, this comprised 3.0% of all ICU admissions during the study period (95% confidence interval [CI] 2.6%-3.5%). Aetiology was acute myocardial infarction (AMI) in 48%. The commonest vasoactive treatment was noradrenaline (56%) followed by adrenaline (46%) and dobutamine (40%). Mechanical circulatory support was used in 30%. Overall in-hospital mortality was 55%. After multivariable logistic regression, age (odds ratio [OR] 1.04, 95% CI 1.02-1.06), admission lactate (OR 1.10, 95% CI 1.05-1.19), Society for Cardiovascular Angiographic Intervention stage D or E at presentation (OR 2.16, 95% CI 1.10-4.29) and use of adrenaline (OR 2.73, 95% CI 1.40-5.40) were associated with mortality. Conclusions: In Scotland the prevalence of cardiogenic shock was 3% of all ICU admissions; more than half died prior to discharge. There was significant variation in treatment approaches, particularly with respect to vasoactive support strategy.

Gabapentin toxicity in renal failure: the importance of dose adjustment.

OBJECTIVE: This case report outlines a significant type of morbidity due to continued use of gabapentin during an episode of acute renal failure. Setting. University teaching hospital. DISCUSSION: Gabapentin is widely used in the management of pain. It is entirely excreted through the renal system so this needs to be considered in any patient becoming acutely ill and developing renal failure. We describe a patient who developed significant deterioration in her conscious level due to iatrogenic gabapentin overdose. CONCLUSION: All doctors need to be aware of the need to review the indications for gabapentin use during periods of acute illness, especially with regard to renal impairment. Off-label use should be discouraged.

Evaluation of a continuous glucose monitor in an unselected general intensive care population.

OBJECTIVE: To assess the accuracy of the Guardian REALTime continuous glucose monitoring system (Medtronic MiniMed, Northridge, Calif, USA) in critically ill adults compared with standard bedside point-of-care testing of capillary and arterial blood glucose levels. SETTING: An 18-bed mixed university tertiary referral intensive care unit, July to December 2006. MAIN OUTCOME MEASURES: Glucose measurements by the Guardian subcutaneous monitoring system were compared with simultaneous measurements of capillary and arterial blood glucose levels. Correlation between the different methods was determined by linear regression, using capillary blood glucose values as the "gold standard", and was further analysed by Bland and Altman plots. RESULTS: 17 emergency-admission mechanically ventilated adults were studied. A total of 1101 glucose measurements were available for analysis (from Guardian, 371; capillary blood samples, 373; and arterial blood samples, 357). With an a-priori acceptable difference of +/-1mmol/L, the Guardian system did not perform well enough to replace current methods of glucose measurement. There was also significant discrepancy between arterial and capillary blood glucose measurements. These common methods of intermittent blood glucose sampling are therefore not interchangeable. CONCLUSION: The Guardian REAL-Time continuous glucose monitoring system cannot replace current methods of blood glucose measurement at a glucose threshold of +/-1mmol/L. It may have role as an early warning detection system for hypo- or hyperglycaemia, but this needs to be evaluated in a prospective study of extremes of blood glucose levels in a critically ill population. Glucose measurements in arterial and capillary blood samples with a point-of-care glucometer also showed wide discrepancies.

Analysis of blood glucose measurements using capillary and arterial blood samples in intensive care patients.

OBJECTIVE: To analyse agreement between two methods for blood glucose measurement in intensive care patients: capillary blood using a reagent strip and glucometer with arterial blood using a blood gas analyser. DESIGN AND SETTING: Prospective, single-centre, observational study in a 12-bed tertiary referral intensive care unit. MEASUREMENTS: Blood glucose levels were measured in consecutive patients using simultaneous measurements of capillary blood samples using glucometry and from a multi-electrode arterial blood gas analyser. An a priori subgroup of patients with tissue hypoperfusion was identified (defined as systolic blood pressure <90 mmHg or vasopressor dependency). A total of 493 paired measurements were obtained; 75 of these were from patients with systemic hypoperfusion. RESULTS: Overall, the mean difference (bias) was 0.12 mmol/l (2.15 mg/dl) and precision 0.77 mmol/l (13.8 mg/dl); 95% limits of agreement were -0.14 and 1.66 mmol/l (-2.5 and 29.8 mg/dl). In patients with systemic hypoperfusion the bias was 0.24 mmol/l (4.0 mg/dl) and precision 0.9 mmol/l (16.2 mg/dl); 95% limits of agreement -2.05 and 1.58 mmol/l (36.8 and 28.4 mg/dl). CONCLUSIONS: In a general population of intensive care patients, there is statistical agreement between blood glucose measured from capillary blood glucometry and arterial blood gas analysis. However, in patients with systemic hypoperfusion, the accuracy of agreement between these two measurement techniques may be such that that biochemical hypoglycaemia (<2.5 mmol/l, 44.9 mg/dl) may go undetected if used interchangeably.