When used for vessel location and catheter placement real-time, ultrasound guidance or Doppler ultrasound guidance improves success rates and decreases the complications associated with internal jugular and subclavian venous catheter placement.

OBJECTIVE -To test the hypothesis that enzymes conventionally associated with liver dysfunction (aspartate aminotransferase, alanine aminotransferase, ␥-glutamyltransferase [GGT], and alkaline phosphatase) may predict diabetes. RESEARCH DESIGN AND METHODS-From a population-based diabetes survey, we selected 1,441 men and women in whom serum enzyme levels were Յ3 SDs of the mean population value, alcohol intake was Ͻ250 g/week, and hepatitis B and C virus testing was negative. At follow-up (7 years), 94 subjects developed diabetes and 93 impaired glucose tolerance (IGT).RESULTS -At baseline, all four enzymes were related to most of the features of the metabolic syndrome. After controlling for sex, age, adiposity/fat distribution, alcohol intake, serum lipids, and blood pressure, higher alanine aminotransferase and GGT values were significantly (P Ͻ 0.01) associated with both IGT and diabetes, whereas alkaline phosphatase was associated with diabetes only (P ϭ 0.0004) and aspartate aminotransferase with IGT only (P ϭ 0.0001). Raised GGT alone was associated with all the features of the metabolic syndrome. Raised GGT was a significant predictor of either IGT or diabetes (odds ratio 1.62 [95% CI 1.08 -2.42] top quartile vs. lower quartiles, P Ͻ 0.02) after controlling for sex, age, adiposity/fat distribution, alcohol consumption, fasting plasma insulin and proinsulin levels, and 2-h postglucose plasma glucose concentrations.CONCLUSIONS -Although mild elevations in liver enzymes are associated with features of the metabolic syndrome, only raised GGT is an independent predictor of deterioration of glucose tolerance to IGT or diabetes. As GGT signals oxidative stress, the association with diabetes may reflect both hepatic steatosis and enhanced oxidative stress. Diabetes Care 28:1757-1762, 2005A syndrome characterized by liver steatosis, lobular hepatitis, and chronically elevated serum alanine aminotransferase (ALT) concentrationstermed nonalcoholic fatty liver disease (NAFLD), or nonalcoholic steatohepatitis (NASH), depending on the degree of parenchymal inflammation-has been identified in patients with negligible alcohol intake (1,2). These patients are often obese and dyslipidemic (3-6). In cross-sectional studies, NAFLD is associated with insulin resistance irrespective of BMI, fat distribution, and glucose tolerance (1,7,8). On these grounds, it has been suggested that hyperinsulinemia and insulin resistance may play a role in the pathogenesis of NAFLD (1) and that NAFLD is a feature of the metabolic syndrome (9).In a prospective study in Pima Indians, serum ALT concentrations were related to both hepatic insulin resistance and later decline in hepatic insulin sensitivity (10). In contrast, aspartate aminotransferase (AST) and ␥-glutamyltransferase (GGT) concentrations were unrelated to changes in hepatic insulin action (10). Based on previous findings (1,2), Vozarova et al. (10) suggested that a raised ALT reflects fatty changes in the liver and that this abnormality antedates the development of type 2 diabete...

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Fasting plasma glucose concentrations (FPG) predict development of type 2 diabetes. Whether hyperglycemia evolves from normoglycemia gradually over time or as a step increase is not known. We measured plasma glucose and insulin levels during oral glucose testing in 35-to 64-year-old men and nonpregnant women from a population-based survey (Mexico City Diabetes Study) at baseline (n ‫؍‬ 2,279) and after 3.25 (n ‫؍‬ 1,740) and 7 years (n ‫؍‬ 1,711) of follow-up. In subjects with normal glucose tolerance (NGT) on all three occasions (nonconverters; n ‫؍‬ 911), FPG increased only slightly (0.23 ؎ 0.79 mmol/l, mean ؎ SD; P < 0.0001) over 7 years. In contrast, conversion to diabetes among NGT subjects (n ‫؍‬ 98) was marked by a large step-up in FPG regardless of time of conversion (3.06 ؎ 2.57 and 2.94 ؎ 3.11 mmol/l, respectively, at 3.25 and 7 years; P < 0.0001 vs. nonconverters). Likewise, in subjects who converted to diabetes from impaired glucose tolerance (n ‫؍‬ 75), FPG rose by 3.14 ؎ 3.83 and 3.12 ؎ 3.61 mmol/l (P < 0.0001 vs. nonconverters). Three-quarters of converters had increments in FPG above the 90th percentile of the corresponding increments in nonconverters. Converters had higher baseline BMI (30.4 ؎ 4.9 vs. 27.3 ؎ 4.0 kg/m 2 ; P < 0.001) and fasting plasma insulin values (120 ؎ 78 vs. 84 ؎ 84 pmol/l; P < 0.02) than nonconverters; however, no consistent change in either parameter had occurred before conversion. In contrast, changes in 2-h postglucose insulin levels between time of conversion and preceding measurement were significantly (P < 0.0001) related to the corresponding changes in FPG in an inverse manner. We conclude that, within a 3-year time frame, the onset of diabetes is very often rapid rather than gradual and is in part explained by a fall in glucose-stimulated insulin response. Diabetes 53:160 -165, 2004 D evelopment of type 2 diabetes is, to some extent, a predictable event. Several studies in different populations have identified anthropometric and metabolic characteristics that increase the likelihood that a person with initially normal glucose tolerance (NGT) will progress to diabetes over a specified period of time (1-3). Thus, family history of diabetes and obesity are potent risk factors amplified by increasing age. In addition, both fasting hyperinsulinemia and the fasting plasma glucose concentration (FPG) itself mark, independent of one another, an enhanced risk of developing the disease (4,5). In the combined analysis of three prospective studies (6), the presence of one or more components of the metabolic syndrome, namely, hyperinsulinemia, dyslipidemia, hypertension, and glucose intolerance, predicted the emergence of diabetes over 8 years of follow-up. Among individuals with impaired glucose tolerance (IGT), the rate of progression to overt diabetes is higher than among people with NGT by a factor of 2-10 (7,8).That a higher, if still normal, FPG shares with other risk markers the ability to predict future hyperglycemia has led to what probably is the concept prevailing amo...

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Conclusions: Use of intermittent heparin flushes at doses of 10 U/ml in peripheral venous catheters locked between use had no benefit over normal saline flush. Infusion of low dose heparin through a peripheral arterial catheter prolonged the duration of patency but further study is needed to establish its benefit for peripheral venous catheters.

Microalbuminuria is associated with increased cardiovascular mortality in both diabetic and non-diabetic subjects. A number of studies have indicated that insulin resistance, increased blood pressure and dyslipidaemia precede the onset of clinical diabetes. We examined various correlates of microalbuminuria in 1,298 non-diabetic subjects who participated in the Mexico City Diabetes Study, a population-based study of diabetes and cardiovascular risk factors. Both parental history of diabetes and impaired glucose tolerance were significantly associated with microalbuminuria. These results were not explained by differences in age or blood pressure between subjects with or without a parental history of diabetes or impaired glucose tolerance. In addition, subjects with microalbuminuria had increased 2-h insulin and triglyceride concentrations, a higher prevalence of hypertension, and decreased high density lipoprotein cholesterol concentrations relative to subjects without microalbuminuria. These results that microalbuminuria may be a feature of the prediabetic state.

Tunneling decreases central venous catheter-related infections. However, current evidence does not support routine tunneling until its efficacy is evaluated at different placement sites and relative to other interventions.