An electronic tool for visual feedback to monitor the adherence to quality indicators in intensive care medicine.

Evidence-based medicine is often inadequately implemented in intensive care units (ICU); the aim of this study was to improve its implementation via a technical feedback system, using key performance indicators (KPI). The study evaluated 205 patients treated in a cardiac surgical ICU over a 6-month period (3 months before and 3 months after implementation of the feedback system). KPI adherence rates for sedation, delirium and pain monitoring, and completion of a weaning protocol before and after the implementation of the feedback system, were compared. Adherence rates for pain and delirium monitoring, and implementation of the weaning protocol, were significantly increased by the intervention. Adherence to KPIs for sedation, which were high at baseline, could not be further improved. Daily display of KPI implementation had a positive effect on adherence to standard operating procedures. Adherence to guidelines may be improved by using this feedback system as part of the clinical routine.

Ultrasound and the blood-brain barrier.

High intensity focused ultrasound was employed to modify the permeability of the normal feline and canine blood-brain barrier (BBB) to a circulating vital dye--Evans blue (EB). The threshold doses (W sec/cm2) for focally increasing the permeability of the BBB in white matter (WM) and gray matter (GM) were as follows: internal capsule (WM)--340 to 680; thalamus (GM)--approximately 1326; and caudate nucleus (GM)--2284 to 2952. In the presence of supralesioning doses of ultrasound, the cross sectional area occupied by the EB was consistently greater than that of the attendant nonhemorrhagic lesion--thus suggesting that BBB changes may be inducible at sublesioning doses. These findings, in conjunction with those of others, suggest that high intensity focused ultrasound may have a role in the treatment of brain tumors based on cell destruction by two mechanisms: (a) direct, by the ultrasound and (b) indirect, by an antineoplastic agent which is delivered via an ultrasonically modified BBB.

Relationship of functional recovery to scar contraction after myocardial infarction in the canine left ventricle.

We have previously reported that regional wall motion abnormalities in a canine model of acute myocardial infarction may show substantial improvement in the first 6 weeks after infarction. To determine whether the mechanism of this improvement in function is the result of scar contraction within the infarct, we studied the relationship between changes in regional wall motion defined by cross-sectional echocardiography and the regional concentration of radioactive microspheres injected immediately before coronary occlusion and sampled 6 weeks after occlusion. Eight dogs underwent serial echocardiographic and microsphere blood flow measurements immediately before and 30 minutes, 48 hours, 1 week, 3 weeks, and 6 weeks after ligation of the left anterior descending or the left circumflex coronary artery. Wall motion and blood flow were measured in the short-axis section of the left ventricle at the level of the midpapillary muscle in each 10-degree radial segment around the circumference of the ventricle. Infarct histology was assessed at 6 weeks by means of the same radial coordinate system. Control data were collected in a similar manner from four dogs that underwent sham operations and had no histologic evidence of infarction. In all of the animals with infarcts, but not in the sham animals, the calculated preocclusion endocardial and epicardial blood flow values in the histologic infarct zone (252 +/- 44 and 168 +/- 17 ml/min/100 gm, respectively, mean +/- SEM) were significantly higher than those in the normal opposite wall (endocardial: 106 +/- 3 ml/min/100 gm, p less than 0.01); epicardial: 108 +/- 3 ml/min/100 gm, p less than 0.01. The location and circumferential extent of myocardium showing this elevation of preocclusion blood flow correlated well (r = 0.93, p less than 0.001) with the location and circumferential extent of the histologic infarct. The amount of wall motion abnormality, measured from the "correlation plot area," decreased significantly from its maximum value of 39 +/- 3 degrees at 48 hours after coronary occlusion to 3 +/- 1 degrees (p less than 0.001) at 6 weeks after occlusion. The ratio of the preocclusion transmural blood flow in the infarct zone to that in the noninfarct zone, a measure of the condensation of the microspheres injected before coronary occlusion, and therefore of the degree of scar contraction at 6 weeks, correlated well (r = 0.83, p less than 0.01) with the recovery of wall motion 6 weeks after infarction.(ABSTRACT TRUNCATED AT 400 WORDS)

The natural history of regional dysfunction in a canine preparation of chronic infarction.

We used a canine preparation of experimental infarction to study the natural course of echocardiographically defined regional wall motion abnormalities in the 6 weeks after acute coronary ligation. Eight dogs underwent serial short-axis echocardiographic evaluation and microsphere blood flow determinations at control, and 30 min, 48 hr, 1 week, 3 weeks, and 6 weeks after acute coronary artery ligation. Wall motion analysis and blood flow calculations were applied to 10 degree radial segments of the left ventricle (short axis) and correlated to the size and extent of infarction as defined histologically at 6 weeks. All animals had at least 50% transmural histologic infarction. The ratio of flow in infarcted tissue vs noninfarcted myocardium fell to 0.40 +/- 0.13 for endocardium and 0.56 +/- 0.13 for epicardium at 30 min after ligation, but recovered to 0.83 +/- 0.15 for endocardium and 1.12 +/- 0.11 for epicardium by 6 weeks. The maximum circumferential extent of abnormal regional wall motion was observed at 48 hr after infarction (mean circumferential extent = 51%), but was resolved to a significant extent by 6 weeks (circumferential extent = 21%, p less than .001). Four animals had virtually normal wall motion by 6 weeks after infarction. Segment-by-segment regional dysfunction correlated highly with the regional transmural reduction in blood flow of 20% )r = .89, p = .0001) for the experiment as a whole, but the echocardiogram tended to underestimate the size of the histologic infarct at 6 weeks.(ABSTRACT TRUNCATED AT 250 WORDS)