Performance of Automated ASPECTS Software and Value as a Computer-Aided Detection Tool.

BACKGROUND AND PURPOSE: ASPECTS quantifies early ischemic changes in anterior circulation stroke on NCCT but has interrater variability. We examined the agreement of conventional and automated ASPECTS and studied the value of computer-aided detection. MATERIALS AND METHODS: We retrospectively collected imaging data from consecutive patients with acute ischemic stroke with large-vessel occlusion undergoing thrombectomy. Five raters scored conventional ASPECTS on baseline NCCTs, which were also processed by RAPID software. Conventional and automated ASPECTS were compared with a consensus criterion standard. We determined the agreement over the full ASPECTS range as well as dichotomized, reflecting thrombectomy eligibility according to the guidelines (ASPECTS 0-5 versus 6-10). Raters subsequently scored ASPECTS on the same NCCTs with assistance of the automated ASPECTS outputs, and agreement was obtained. RESULTS: For the total of 175 cases, agreement among raters individually and the criterion standard varied from fair to good (weighted κ = between 0.38 and 0.76) and was moderate (weighted κ = 0.59) for the automated ASPECTS. The agreement of all raters individually versus the criterion standard improved with software assistance, as did the interrater agreement (overall Fleiss κ = 0.15-0.23; P < .001 and .39 to .55; P = .01 for the dichotomized ASPECTS). CONCLUSIONS: Automated ASPECTS had agreement with the criterion standard similar to that of conventional ASPECTS. However, including automated ASPECTS during the evaluation of NCCT in acute stroke improved the agreement with the criterion standard and improved interrater agreement, which could, therefore, result in more uniform scoring in clinical practice.

Cold tolerance and the regulation of cardiac performance and hemolymph distribution in Maja squinado (Crustacea: decapoda).

Elevated Mg(2+) levels in the hemolymph ([Mg(2+)](HL)) of brachyuran crabs have recently been demonstrated to limit cold tolerance by reducing motor and circulatory activity. Therefore, the limiting function of elevated [Mg(2+)](HL) on circulatory performance and arterial hemolymph flow was investigated by the pulsed-Doppler technique in the spider crab Maja squinado during progressive cooling from 12 degrees to 0 degrees C. [Mg(2+)](HL) were reduced from control levels of 39.9 mmol L(-1) to levels of 6.1 mmol L(-1) by incubation in magnesium reduced seawater. At 12 degrees C cardiac output was 13.9+/-2.4 mL kg(-1) min(-1) and stroke volume 0.2+/-0.04 mL kg(-1) min(-1) in control animals. In [Mg(2+)](HL)-reduced animals cardiac output increased to 43.6+/-5.0 mL kg(-1) min(-1) and stroke volume rose to 0.6+/-0.1 mL kg(-1) min(-1). Temperature reduction in control animals revealed a break point at 8 degrees C linked to a major redirection of hemolymph flow from lateral to sternal and hepatic arteries. Cardiac output and heart rate dropped sharply during cooling until transiently constant values were reached. Further heart rate reduction occurred below 4.5 degrees C. Such a plateau was not detected in [Mg(2+)](HL)-reduced animals where the break point decreased to 6 degrees C, also indicated by a sharp drop in heart rate and cardiac output and the redirection of hemolymph flow. It is concluded that progressive cooling brings the animals from a temperature range of optimum cardiac performance into a deleterious range when aerobic scope for activity falls before critical temperatures are reached. Reduction of [Mg(2+)](HL) shifts this transition to lower temperatures. These findings support a limiting role for [Mg(2+)](HL) in thermal tolerance.

Haemodynamic changes associated with atropine/neostigmine administration. A non-invasive investigation.

Stroke volume, systolic time intervals and related index variations induced by atropine/neostigmine (AN) (0.75 mg/l mg) decurarization mixture were investigated by non-invasive methods (ECG, phonocardiogram, thoracic impedance) in 15 anaesthetized normocapnic patients in a stable state after induction of anaesthesia and prior to surgical stimulation. Data showed decrease in mean heart rate (HR) (initial value: 82 beats/min; after 10 min: 57 beats/min; P less than 0.001) accompanied by an increase in stroke volume (SV) (initial value: 75 ml, after 10 min: 100 ml; P less than 0.001). No alterations in myocardial contractility were noted with the systolic time intervals (PEP, PEP/LVET, 1/PEP2). Under the conditions of the study, the negative chronotropic effect of AN mixture was not accompanied by a negative inotropic state.

Analgesic anesthesia with fentanyl (F) and sufentanil (SF) in coronary surgery. A double blind study.

The study includes 54 unselected coronary patients. Fifty underwent one or several aortocoronary bypass associated with left ventricular resection (3 times), mitral valve replacement (twice), aortic valve replacement (twice). Four patients underwent left ventricular resection alone. The operations were performed under analgesic anesthesia with sufentanil (SF) or fentanyl (F) with a double blind protocol. The ratio of concentrations of the two analgesics was SF/F = 1/10. Flunitrazepam induced and maintained sleep. After having reached by increments the total dose of 1.5 mg F/M2 or 0.15 mg SF/M2, droperidol was then added in small amounts of 3.75 mg/M2, alternating with the analgesic both being given as needed to maintain blood pressure between 100 and 120 mm Hg, in order to potentiate the level of analgesia reached and prevent vasoconstriction. Under this setting tachycardia (heart rate greater than 100 beats/min. and less than 120 beaths/min.) was observed before ECC in only 7.4% of cases with both analgesics and brief episodes of hypertension (mean maximum systolic blood pressure 140.7 +/- 20.3 mm Hg seen with SF exclusively). There was neither postoperative hypertension (except with 6 out of the 7 known hypertensive patients) nor low cardiac output, nor arbythmia. No patients remained in intensive care unit more than 24 hour. No difference attribuable to the used analgesic was detectable in the early and late follow-up in both series. On an average, the patients were discharged on postoperative day 10 in a valid condition.