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Purpose: The surgical resident experience with trauma has changed. Many residents are exposed to predominantly nonoperative patient care experiences while on trauma rotations. Data from a large multicenter study were analyzed to estimate surgical resident exposure to trauma laparotomy, diagnostic peritoneal lavage (DPL), and focused abdominal sonography for trauma (U/S). Methods: Centers completed a self-report questionnaire on their institutional demographics, admissions, and procedure for a 2-year period (1998-1999). Results: A total of 82 trauma centers that provide resident teaching were included. The included centers represent over 247,000 trauma admissions. The majority of trauma centers (65.9%) had > 80% blunt injury. Although all centers performed laparotomies, other results were more variable. For U/S, 24.2% performed none at all and 47.0% performed fewer than two U/S examinations per month. For DPLs, 3.8% performed none and 66.7% performed fewer than two per month. Assuming 1 night of 4 on call, the average surgical resident training at a trauma center performing > 80% blunt trauma has the potential to participate in only 15 trauma laparotomies, 6 diagnostic peritoneal lavages, and 45 ultrasound examinations per year. In addition, the resident will care for an average of 500 blunt trauma patients before performing a splenectomy or liver repair. Conclusion: Surgical resident experience on most trauma services is heavily weighted to nonoperative management, with a relatively low number of procedures, little experience with DPL, and highly variable experience with ultrasound. These data have serious implications for resident training and recruitment into the specialty.

Background: Short- and intermediate-term use of cardiac glycosides promotes inotropy and improves the ejection fraction in systolic heart failure. Aim: To determine whether chronic digitalization alters left ventricular function and performance. Methods: Eighty patients with mild-to-moderate systolic heart failure (baseline ejection fraction ≤ 45%) participated from our institution in a multi-center, chronic, randomized, double-blind study of digitalis vs. placebo. Of the 40 survivors, 38 (20 allocated to the digitalis arm and 18 to the placebo arm) were evaluated at the end of follow-up (mean, 48.4 months). Left ventricular systolic function was assessed by both nuclear ventriculography and echocardiography. The ejection fraction was measured scintigraphically, while the ventricular volumes were computed echocardiographically. Results: The groups did not differ, at baseline or end-of-study, with respect to the ejection fraction and the loading conditions (arterial pressure, ventricular volumes and heart rate) by either intention-to-treat or actual-treatment-received analysis. Over the course of the trial, the digitalis arm exhibited no significant increase in the use of diuretics (18%, P - 0.33), in distinction from the placebo group (78%, P - 0.004), and a longer stay on study drug among those patients who withdrew from double-blind treatment (28.6 vs. 11.4 months, P - 0.01). Conclusion: Following chronic use of digitalis for mild-to-moderate heart failure, cross-sectional comparison with a control group from the same inception cohort showed no appreciable difference in systolic function or performance. Thus, the suggested clinical benefit cannot be explained by an inotropic effect.

In previous experiments excess vitamin A, administered to pregnant rats during the early stages of gestation, was found to interfere with the mitotic activity of the neuro-epithelial cells bordering the neural groove. The result was exencephaly and anencephaly in a high percentage of the newborn. The present work was undertaken to examine the influence of hypervitaminosis A on the behavior of the neuro-epithelial cells of the cerebral hemisphere and the subsequent migration and differentiation of the neuroblasts during the later stages of development. Swiss-Webster mice were treated with large doses of vitamin A on days 14 and 15 of gestation. When subsequently the cell cycle of the neuro-epithelial cells lining the lateral ventricle of 15-day fetuses was determined, vitamin A was found to increase both the duration of the mitosis and DNA synthetic period. In comparison with the controls, the total generation time was prolonged by approximately 40%. Since almost all neuroblasts of the cerebral cortex originate in the neuro-epithelial zone bordering the lateral ventricle, the total number of neuroblast formed is in all probability less than normal. Indeed, prelimiinary data on the number of cells present in the cerebral cortex of 10-day postnatal rats treated with excess vitamin A toward the end of pregnancy showed a decrease in cell density, indicating either a reduction in the number of cells formed or a degeneration of existing cells. In a second experiment Swiss-Webster mice were treated with excess vitamin A during three successive days in the second half of pregnancy. The cerebral cortex of the newborn was examined one to ten days after birth. Histological examination revealed a rather sharply delineated zone of abnormal cells characterized by a lightly stained cytoplasm, a thick nuclear memberane, a desely stained nucleoplasm and several dark chromatin bodies. When the position of the zone containing the abnormal cells was analyzed and correlated with the day of formation in the neuroepithelial zone, it was found that the affected cells were neuroblasts already present in the cortex before the vitamin treatment was started. This indicates that excess vitamin A, given to pregnant mice during the later stages of gestation, influences the development of the cerebral cortex, not only by interfering with the production of cells in the neuroepithelial zone, but also by affecting the differentiation of existing neuroblasts. As a result of these anomalies, some of the newborn appeared to have abnormal patterns of behavior.

Blood cultures were obtained from 19 patients with thermal injury of from 7 to 73% (mean 38%) of the total body surface area before, during, and after manipulation of the burn wound. Procedures were separated into a group which required general anesthesia and those which did not, and extent of traum

Arterial hemoglobin oxygen saturation measured with the Datascope ACCUSAT pulse oximeter was compared with simultaneous arterial hemoglobin oxygen saturation measurements in healthy adult volunteers. One hundred thirty-five arterial blood samples ranging in saturation from 63 to 100% were obtained from 15 adults, aged 20 to 43 years. These subjects had different skin pigmentation, hematocrit, and smoking habits. Steady-state hypoxia was achieved by varying the inspired oxygen concentration between 10 and 21%. Readings from the Datascope ACCUSAT pulse oximeter and the Hewlett-Packard 47201A ear oximeter were compared with arterial blood samples analyzed by the Instrumentation Laboratories IL 282 in vitro CO-Oximeter. The equation for the best fitted linear regression line between the ACCUSAT pulse oximeter and the reference IL 282 CO-Oximeter was: ACCUSAT = 1.08(IL) - 6.86. The linear regression analysis revealed a high degree of correlation (r = 0.99), and a small standard error of the estimate (SEE = 1.29%). Simultaneous comparisons between arterial hemoglobin oxygen saturation measured with the ACCUSAT pulse oximeter and the Hewlett-Packard ear oximeter also showed a close correlation (r = 0.99, SEE = 1.47%). A similar comparison between the ACCUSAT and the Ohmeda 3700 pulse oximeter revealed good correlation (r = 0.99, SEE = 1.72%). We found that the ACCUSAT pulse oximeter is an accurate instrument for measuring arterial hemoglobin oxygen saturation noninvasively in the range between 60 and 100%.

Pregnant rats and mice were treated with large doses of vitamin A to examine its effect on the closure of the neural groove in the developing embryo. In the rat the most effective dose was 30,000 U.S.P. units given at day 8, 9, and 10 of pregnancy. Twenty-six per cent of the implanted embryos showed anencephaly and/or myeloschisis. In the mouse the results of vitamin A treatment were inconsistent. In 12-day rat embryos, the lateral walls of the diencephalon and mesencephalon were slightly everted. Mitotic neuro-epithelial cells were frequently piled up two or three rows thick, causing a disruption of the internal limiting membrane. Many cells were characterized by a bleb-like cytoplasmic evagination protruding into the lumen. During the following days, the everted walls of the diencephalon and mesencephalon expanded farther and farther over the sides of the head, thereby often covering the lateral hemispheres and the eyes. Although the hemispheres were displaced by the everted diencephalic plates and the eyes were frequently buried deep inside the head, histological differentiation proceeded normally and a primitive cerebral cortex as well as normal eye structures were observed. The accumulation of mitotic figures, the formation of cytoplasmic protrusions, and the presence of small neuro-epithelial rosettes throughout the brain were the most striking cytological anomalies. By the eighteenth day of development, small hemorrhages occurred in the mesenchyme surrounding the brain and degeneration became apparent. At birth a small amount of degenerated brain tissue was all that remained from the large exencephalic brain, and the newborn had the appearance of an anencephalic. It is concluded that large doses of vitamin A prevent the neural groove from closing, possibly by interfering with the Cell membrane and/or the mitotic activity of the neuro-epithelial cells.