Electrical nanowell diagnostics sensors for rapid and ultrasensitive detection of prostate-specific antigen.

AIM: Alumina nanowell based disposable diagnostic biosensor for detecting and quantifying levels of prostate-specific antigen (PSA) from human serum has been designed, fabricated and tested. MATERIALS & METHODS: The biosensors were designed by integrating nanoporous alumina membranes onto printed circuit board platforms, resulting in the generation of high-density nanowell arrays with gold base electrodes. The size and density of the nanowells were leveraged toward achieving sieving action for size-based exclusion of nonspecific molecules and size-based confinement of the target PSA molecules. RESULTS & CONCLUSION: We demonstrated PSA detection between 0.01 and 1000 ng/ml and detection and quantification of PSA from a 17 patient cohort validated using the Beckman Access system with >95% correlation.

Evaluating an insulin infusion protocol in an acute care setting.

OBJECTIVE: The objective of the present study was to evaluate the adherence, safety, and effectiveness of a paper versus an electronic insulin infusion protocol. DESIGN: This quasi-experimental implementation study compared experimental and control groups using a nonrandomized prospective cohort design. SETTING: The study was performed at 2 surgical units within a federal tertiary care teaching hospital. SAMPLE: Fifty-eight registered nurses volunteered. METHODS: We compared time intervals using electronic time stamps from glucometers and insulin infusion devices to measure protocol adherence. We assessed perceived adherence using a nurse survey, and, to evaluate safety, we reviewed each paper protocol infusion calculation for correctness. FINDINGS: Median times from blood glucose acquisition to infusion rate adjustment did not differ significantly between groups (P = .215). The majority of infusions (96.6%) had glucose acquisition times within the acceptable range. Median values of time to next "glucose due" did not differ significantly (P = .88), and relative variation in median glucose reporting times did not differ significantly between groups (P = .16). Evaluation of 877 paper protocol entries demonstrated a 10.7% (n = 94) calculation error rate. Registered nurses within the electronic group reported greater ease in balancing workload when compared with paper protocol use (P = .03). Attitudes did not differ significantly between groups in areas of determining infusion adjustment, bolus insulin dose, next glucose due, ease of access, understanding protocol, or overall satisfaction. CONCLUSIONS: This study demonstrates that one can adhere to an insulin infusion protocol, regardless of the format (paper or electronic), in the medical-surgical setting. Our results suggest there are safety and nurse workload benefits when an electronic protocol was used. IMPLICATIONS: Adherence, safety, and effectiveness can be achieved when using insulin infusion in the medical-surgical setting.

Impact of combination medical therapy on mortality in vascular surgery patients.

BACKGROUND: Th use of beta-blockers or statins has been associated with decreased mortality after noncardiac surgery. There are no prior perioperative studies of concurrent use of other cardioprotective drugs. OBJECTIVE: To ascertain whether combinations of aspirin, beta-blockers, statins, and/or angiotensin-converting enzyme (ACE) inhibitors were associated with decreased mortality 6 months after vascular surgery. PATIENTS AND DESIGN: We performed a retrospective cohort study on the 3020 patients who underwent vascular surgery between January 1998 and March 2005 at 5 regional Veterans Affairs (VA) medical centers. The Cochran-Mantel-Haenszel test was used to assess associations with 6-month all-cause mortality for the combination drug exposures compared to no exposure while adjusting for propensity score. RESULTS: Exposure to all 4 of the study drugs compared to none had a propensity-adjusted relative risk (aRR) of 0.52 (95% confidence interval [CI], 0.26-1.01; P = 0.052), number needed to treat (NNT) 19; 3 drugs vs. none, aRR 0.60 (95% CI, 0.38-0.95; P = 0.030), NNT 38; 2 drugs vs. none, aRR 0.68 (95% CI, 0.46-0.99; P = 0.043), NNT 170; and 1 drug vs. none, aRR 0.88 (95% CI, 0.63-1.22; P = 0.445). ACE inhibitor exposure was common in all combinations. CONCLUSIONS: Combination use of 2 to 3 study drugs, some of which included ACE inhibitors, was associated with decreased mortality after vascular surgery. Combination use of all 4 study drugs was not statistically significant due to the small number of events in this group. Further prospective studies of combination perioperative aspirin, beta-blockers, statins, and ACE inhibitors are warranted.

Association of ambulatory use of statins and beta-blockers with long-term mortality after vascular surgery.

BACKGROUND: The use of drugs to improve postoperative outcomes has focused on short-term end points and centered on beta-blockers. Emerging evidence suggests statins may also improve postoperative outcomes. OBJECTIVE: We sought to ascertain if the ambulatory use of statins and/or beta-blockers was associated with a reduction in long-term mortality after vascular surgery. DESIGN: Retrospective cohort study with a median follow-up of 2.7 years. SETTING: Regional multicenter study at Veterans Affairs medical centers. PATIENTS: Three thousand and sixty-two patients presenting for vascular surgery. MEASUREMENTS: Patients were categorized as using statins or beta-blockers if they filled a prescription for the study drug within 30 days of surgery. Survival analyses, propensity score methods, and stratifications by the revised cardiac risk index (RCRI) were performed. RESULTS: Propensity-adjusted ambulatory use of statins and beta-blockers was associated with a reduction in mortality over the study period compared with nonuse of these medications hazard ratio [HR] = 0.78 [95% CI: 0.67-0.92], P = .0021, and number needed to treat (NNT) = 22 for statins; HR = 0.84 [95% CI: 0.73-0.96], P = .0106, and NNT = 30 for beta-blockers. In addition, for propensity-adjusted use of both statins and beta-blockers compared with neither the HR was 0.56 [95% CI: 0.42-0.74] P < .0001, and NNT was 9. The RCRI confirmed combination statin and beta-blocker use was beneficial at all levels of risk. Use of the combination study drugs by the highest-risk patients was associated with a 33% decrease in mortality after 2 years (P = .0106). CONCLUSIONS: The use of ambulatory statins alone or in combination with beta-blockers is associated with a reduction in long-term mortality after vascular surgery, and combination use benefits patients at all levels of risk.