Effect of Radiographic Contrast Media Shortage on Stroke Evaluation in the United States.

BACKGROUND AND PURPOSE: We performed this study to identify the effect of the nationwide iodinated contrast media shortage due to reduction in GE Healthcare production, initiated on April 19, 2022, on the evaluation of patients with stroke. MATERIALS AND METHODS: We analyzed the data on 72,514 patients who underwent imaging processed with commercial software in a sample of 399 hospitals in United States from February 28, 2022, through July 10, 2022. We quantified the percentage change in the daily number of CTAs and CTPs performed before and after April 19, 2022. RESULTS: The daily counts of individual patients who underwent CTAs decreased (a 9.6% reduction, P = .002) from 1.584 studies per day per hospital to 1.433 studies per day per hospital. The daily counts of individual patients who underwent CTPs decreased (a 25.9% reduction, P = .003) from 0.484 studies per day per hospital to 0.358 studies per day per hospital. A significant reduction in CTPs using GE Healthcare contrast media (43.06%, P < .001) was seen but not in CTPs using non-GE Healthcare contrast media (increase by 2.93%, P = .29). The daily counts of individual patients with large-vessel occlusion decreased (a 7.69% reduction) from 0.124 per day per hospital to 0.114 per day per hospital. CONCLUSIONS: Our analysis reported changes in the use of CTA and CTP in patients with acute ischemic stroke during the contrast media shortage. Further research needs to identify effective strategies to reduce the reliance on contrast media-based studies such as CTA and CTP without compromising patient outcomes.

Different limit to the body's ability of increasing fat-free mass.

It is a common understanding that fat-free mass (FFM) increases with body weight. However, limited information is available as to the relationship between weight increase and changes in body composition. We performed the present study to determine quantitatively the relationship between body composition, total body weight, age, and sex. Body composition data were obtained by isotopic dilution on 273 subjects ranging in body mass index (BMI) from about 13 to 70 kg/m(2). Adipose free tissue (AFT) was modeled as a nonlinear, increase-limited function of body weight. Model parameters were evaluated as functions of sex, age, and height. The relationship between AFT and body weight was very well approximated by means of the nonlinear model (R(2) =.95), with maximal AFT being determined by both sex and height and with AFT growth rate determined only by sex. AFT clearly shows a nonlinear behavior, tending to increase less and less with progressively increasing body weight. With the proposed model, an asymptotic maximal AFT may be postulated. The organism seems to have an intrinsic limitation to how much skeletal muscle development may take place to accommodate the necessities of an ever-increasing load. These limits are different between the sexes, with women tending to approach more rapidly than men a lower maximal AFT for the same height.

The steroid resistance of Crohn's disease.

BACKGROUND: A partial or complete steroid resistance, whose cause is not yet clarified, has been documented in many patients with long-standing Crohn's disease (CD). The primary aim of this study was to evaluate the number and affinity of serum protein steroid-binding sites in steroid-resistant patients with Crohn's disease. A secondary goal was to measure insulin sensitivity, an indirect index of steroid effectiveness, in these patients. METHODS: The study included 8 male steroid-resistant patients with active ileal CD and 6 healthy male volunteers. Corticosteroid binding globulin (CBG), binding capacity and affinity for cortisol were measured. The binding of cortisol to normal human serum and to serum of patients with CD was also determined. Whole body glucose uptake and oxidation were assessed by euglycemic hyperinsulinemic clamp and indirect calorimetry. RESULTS: Crohn's patients showed a significantly greater capacity of serum albumin for cortisol than controls (by about 40%, or about 0.15 moles per mole). Conversely, the binding of cortisol to CBG did not show significant differences between groups. Glucose uptake was higher in Crohn's patients than in normal controls (8.82 +/- 2.50 vs 7.01 +/- 2.24 mg/kgFFM/min; P = 0.036). Basal serum nonesterified fatty acid (NEFA) levels were lower in patients than in controls (459.64 +/- 69.95 vs 1026.48 +/- 112.58 mumol/L; P = 0.002). CONCLUSIONS: The observed increase in albumin binding might limit the bioactivity of cortisol in patients with Crohn's disease and contribute to the decreased effectiveness and weaker side effects of glucocorticoid therapy in these patients. The increased number of cortisol binding sites on albumin from patients with CD might be correlated with the significant decrease in serum NEFA, which may compete with steroids for the same sites.

Hydra: a C-language environment for real-time DOS multitasking at the bedside.

Patient monitoring at the bedside is an inherently parallel job, best handled by multiple individual tasks running concurrently. Cost and diffusion considerations strongly favor the use of PC's at the bedside, but their most widespread operating system, DOS, is not built for multitasking. Hence, a software platform in C language has been prepared, allowing the intermediate programmer to easily write independent modules which will then run simultaneously without conflicts. Such a platform aims at allowing effortless sharing of data among concurrently running processes, while providing strong insulation between tasks, enough to allow multiple copies of any one task to run simultaneously unknown to each other. A cooperative, memory sharing multitasking paradigm has been chosen, which offers fine granularity of timeslicing and low execution overhead at the price of some loss in generality of design. Speed, data exchange capability and number of stackable windows are greater than with commercial packages like Windows or LabWindows. Dynamical reprioritization of tasks is built in, allowing the computerized monitor to focus its attention and resources on urgent tasks.

Reversibility of insulin resistance in obese diabetic patients: role of plasma lipids.

The aim of the present study was to measure whole body glucose uptake (M) and oxidation rate by euglycaemic hyperinsulinaemic clamp and indirect calorimetry in 7 morbidly obese subjects (BMI > 40 kg/m2) at three time points: before bilio-pancreatic diversion (BPD) surgery (Ob); 3 months after surgery POI; and after reaching stable body weight, at least 2 years after surgery POII. A group of 7 control subjects (C), matched groupwise for sex, age and BMI with POII patients, was also studied. The M value at POI was significantly higher than at Ob (49.12 +/- 8.57 vs 18.14 +/- 8.57 mumol.kg-1.min-1). No statistical difference was observed between the POII and C groups. Similarly, glucose oxidation rate was significantly increased at POI with respect to Ob (24.2 +/- 7.23 vs 9.42 +/- 3.91 mumol.kg-1.min-1) and was not significantly different between POII and C. Basal levels of non-esterified fatty acids (NEFA) decreased significantly both from Ob to POI and from POI to POII (1517.1 +/- 223.9 vs 1039.6 +/- 283.4 vs 616.0 +/- 77.6 mumol.1(-1). The same applied to basal plasma triglycerides (2.07 +/- 0.77 vs 1.36 +/- 0.49 vs 0.80 +/- 0.19 g.1(-1). Weight decreased mainly in the late postoperative period (POI to POII 124.28 +/- 11.22 to 69.71 +/- 11.78, 83% of total decrement), rather than in the early postoperative period (Ob to POI 135.25 +/- 14.99 to 124.28 +/- 11.22 kg, 17% of total decrement). We also report the clinical case of a young woman of normal weight, who underwent BPD for chylomicronaemia (secondary to familial lipoprotein lipase deficiency), whose M value, plasma insulin and blood glucose levels were normalized upon normalization of serum NEFA and triglyceride levels as determined by the therapeutic lipid malabsorption. In conclusion, in obese diabetic patients lipid malabsorption induced by BPD causes a definite enhancement of insulin sensitivity and glucose tolerance. This improvement in metabolism is noticeable before the surgery has major effects on body weight. These observations suggest that lowered plasma lipids, rather than weight loss per se, are the cause of the reversibility of insulin resistance.

Respiratory index/pulmonary shunt relationship: quantification of severity and prognosis in the post-traumatic adult respiratory distress syndrome.

The relationship between the respiratory index (RI = alveolar-arterial oxygen gradient [P(A-a)O2] normalized by PaO2) and the pulmonary shunt (Qsp/Qt) has been examined in 929 studies from 240 critically ill post-traumatic patients. Of these, 88 patients (443 studies) were individuals who developed post-traumatic adult respiratory distress syndrome (ARDS) and 152 were patients (486 studies) who did not develop ARDS. This study demonstrates that the RI to Qsp/Qt [RI/(Qsp/Qt)] relationship was significantly (p less than .0001) increased in patients who developed fatal ARDS compared with those who did not develop ARDS, or with those whose ARDS resolved. Because of the increased oxygen consumption (VO2) in ARDS patients in association with their severe limitations in gas exchange (RI) and increased Qsp/Qt, surviving ARDS patients had a significant increase in the cardiac index which resulted in a higher oxygen delivery to VO2 ratio. ARDS patients showed significant (p less than .0001) evidence of increased pulmonary vascular tone, correlated with the increase in the RI/(Qsp/Qt) relationship. In addition, those patients with high RI/(Qsp/Qt) also had increased right ventricular (RVSW) to left ventricular work (LVSW) ratios which were shown to be a direct function of the rise in RI. This increase in both RVSW/LVSW and RI/(Qsp/Qt) ratios was significantly (p less than .0001) correlated with an increased mortality. Thus, the RI/(Qsp/Qt) relationship, which can be obtained from arterial and mixed venous blood gases and saturations only, can be used to predict the severity of the ARDS process as well as important pulmonary vascular and right ventricular overload consequences.