Optimal Disinfection Times for Needleless Intravenous Connectors

BackgroundElimination of catheter-related bloodstream infections is a major focus in health care. According to the Centers for Disease Control and Prevention and the Infusion Nurses Society, the optimal time for needleless connector disinfection has not yet been empirically established.MethodsUsing experimental design and established lab procedure, a 0.5 MacFarland suspension was used to inoculate 172 needleless connectors with bacteria (Staphylococcus aureus, Staphylococcus epidermidis, and Pseudomonas aeruginosa) and allowed to dry for 18 hours. Five groups of connectors (n = 27 per group) were disinfected using 70% isopropyl alcohol with friction for 5, 8, 10, 12, and 15 seconds, and flushed with 0.5 mL nonbacteriostatic sterile normal saline onto sheep-blood agar plates for incubation at 35°C for 48 hours. Bacterial growth (1 colony) was noted on 2 negative controls; therefore, a second sample (n = 172) was tested as above using additional precautions of masking, gloving, and gowning. A third group of connectors was tested using a 0.5 MacFarland suspension containing yeast (Candida albicans).ResultsGroup 1 showed significant (χ²₄ = 37.93; P = .00) and strong (Cramér's V = 0.53; P = .00) associations between scrub time and growth status. Although not statistically significant, Groups 2 and 3 demonstrated clinically significant associations between these factors.ConclusionsAlthough additional research is warranted, our study showed that disinfection times of 5 and 8 seconds were inadequate for reducing bacterial transfer. However, disinfection times of 10, 12, and 15 seconds resulted in comparable, decreased rates of bacterial migration.     

Bipotential effects of estrogen on growth hormone synthesis and storage in vitro

Increased pulses of serum GH coincide with rising estrogens during the reproductive cycle, suggesting estrogen regulation. However, there is lack of agreement about estrogen's direct effects on the pituitary. Pituitaries from cycling female rats were dispersed and plated for 24 h in defined media containing vehicle or 0.001-250 nm 17beta-estradiol. Estrogen (0.01-10 nm) increased the percentages of GH antigen-bearing cells in the anterior pituitary significantly (1.3- to 1.6-fold) and 0.01-1 nm concentrations also stimulated significant increases in GH mRNA-bearing cells and in the integrated OD for GH mRNA. However, 100-250 nm either had no effect or, inhibitory effects on the area of label for GH mRNA. To test estrogen's effects on expression of GHRH receptors, cultures were stimulated with biotinylated analogs of GHRH and target cells detected by affinity cytochemistry. Estrogen increased GHRH target cells in populations from rats in all stages of the cycle tested. Basal expression of GHRH target cells declined at metestrus. Cultures treated with 0-1 nm estrogen were then dual labeled for bio-GHRH followed by immunolabeling for GH with the antirabbit IgG-ImmPRESS peroxidase polymer. Over 98% of GH cells bound GHRH and 90-96% of GHRH-bound cells contained GH in all treatment groups. Thus, low concentrations of estrogen may stimulate expression of more cells with GH proteins, biotinylated GHRH binding sites, and GH mRNA, whereas high concentrations have no effect, or may reduce GH mRNA. These bipotential effects may help explain the different findings reported in the literature.     

Experience with Tolvaptan for Euvolemic and Hypervolemic Hyponatremia in the Acute Care Setting

Background:

Hyponatremia is a common electrolyte disorder and is associated with multiple comorbidities. Management strategies are varied and etiology-dependent. The use of tolvaptan, a vasopressin antagonist, outside of clinical trials has not been well characterized.

Objectives:

To quantify tolvaptan compliance with institutional guidelines and make recommendations concerning reasonable expectations for its role in hyponatremia management.

Methods:

This was a retrospective observational study in a 125-bed community hospital. Patients admitted in 2013 who received at least one dose of tolvaptan were included.

Results:

Thirty-seven patient encounters were evaluated. Tolvaptan was prescribed with 83.7% adherence to the institutional order set. Mean age was 71 ± 16.4 years with 20 (54%) females. Hyponatremia was a contributory cause of admission in 15 (40.5%) patients and offending medications were discontinued in 7 (19%). Causes of hyponatremia included syndrome of inappropriate antidiuretic hormone (SIADH), heart failure, and cirrhosis in 78.3%, 8.2%, and 13.5% of participants, respectively. Management included fluid restriction in 19 (51%) and furosemide in 5 (13.5%), with tolvaptan administration on average 3.2 days after admission. Most patients (78.4%) required ≤2 doses. Sodium concentration was elevated 8 mEq/L by the end of hospitalization. Discharge to palliative care or death occurred in 8 (21.6%). Postdischarge review revealed 3 (8%) maintained sodium concentration ≥130 mEq/dL.

Conclusion:

Tolvaptan was initiated after other interventions and with limited duration per institutional guidelines. This cohort had complicating underlying chronic diseases. These results will be used to refine recommendations with pharmacist input for risk/benefit stratification based on reasonable expectations.     

Clonal evolution and lack of cytogenetic response are adverse prognostic factors for hematologic relapse of chronic phase CML patients treated with imatinib mesylate

We followed 141 patients treated with imatinib mesylate (> 300 mg) for chronicphase chronic myelogenous leukemia (CML) following failure of treatment with interferon. During 12 months from the start of imatinib mesylate treatment, 96.5% achieved a complete hematologic response, 47.0% achieved a major cytogenetic response, and 32.4% achieved a complete cytogenetic response. The proportion of patients with hematologic relapse was 10.9% at 12 months and 14.6% at 18 months. In a univariate Cox regression analysis, the only pretreatment characteristics that correlated with an increased risk of hematologic relapse were hemoglobin level less than 120 g/L (12 g/dL) (P =.02), increased bands in the peripheral blood (P =.01), and clonal evolution (P <.0001). In a multivariate analysis, an elevated platelet count (P =.03) and clonal evolution (P <.0001) were the only significant factors for hematologic relapse. During treatment, the absence of a major cytogenetic response within the first 6 months also significantly correlated with relapse (P =.03). Notably, patients failing to achieve a major cytogenetic response by 6 months had a significantly higher rate of hematologic relapse (27%) compared with those who achieved a major cytogenetic response by 6 months (3%), and patients with clonal evolution had a significantly higher risk of hematologic relapse (50%) than those without clonal evolution (9%).     

Expression of inducible nitric oxide synthase in cultured smooth muscle cells from rat mesenteric lymphatic vessels

OBJECTIVE: The objective was to devise a method for establishing cultures of rat mesenteric lymphatic vessel smooth muscle cells (LSMC) and to investigate if inducible nitric oxide synthase (iNOS) expression could be activated in LSMC treated with bacterial lipopolysaccharide (LPS). METHODS: LSMC were successfully grown from explanted rat lymphatic microvessels and maintained by subculture. Treatment of LSMC for 24 h with LPS (1-100 microg/mL) activated iNOS protein induction, associated with (1) assay of increased nitrite concentrations in the medium representing cellular nitric oxide synthesis, and (2) demonstration of iNOS in cell extracts by Western blotting. RESULTS: The protein synthesis inhibitor cycloheximide (10 microM) blocked both LPS-induced nitrite formation and iNOS protein expression in LSMC. 1400 W (1 microM), a selective iNOS inhibitor, prevented LPS-induced nitrite formation but not iNOS expression. As well as induction of iNOS by LPS, "constitutive" iNOS was present in some cultures, producing nitrite in amounts that were also subsequently reduced after cell treatment with 1400 W. CONCLUSION: Rat mesenteric LSMC produce nitrite and express iNOS in response to bacterial LPS. Cultured LSMC may provide a useful model for studying mechanisms of iNOS induction in relation to possible influences of iNOS upon lymphatic vessel function.     

Inadvertent stenting of patent ductus arteriosus with Amplatzer Vascular Plug.

We report a 12-month old patient who presented for murmur evaluation after percutaneous closure of type C patent ductus arteriosus (PDA) using a 10 mm Amplatzer Vascular Plug (AGA Medical Corporation, Golden Valley, MN) at an outside institution. Echocardiography revealed a large left-to-right shunt through the implanted device, inadvertently stenting the PDA instead of closing it. The patient underwent repeat catheterization with successful coil implantation within the Amplatzer Vascular Plug, completely eliminating the large residual ductal shunt. Although challenging, this case illustrates the technique of implanting coils within this occlusion device. This case also illustrates that occlusion of type C PDA utilizing the Amplatzer Vascular Plug may not only result in incomplete occlusion but also create a potentially worse clinical situation in which the PDA is stretched larger and stented open. Without consideration of simultaneous coil implantation within this device, use of the Amplatzer Vascular Plug might be contraindicated in type C PDA, because there may be no way to ensure successful closure by the Vascular Plug alone.     

Effects of a treatment adherence enhancement program on health literacy, patient-provider relationships, and adherence to HAART among low-income HIV-positive Spanish-speaking Latinos

The impact of an adherence enhancement program for low income HIV-infected Spanish-speaking Latinos on health literacy, patient-provider relationships, and adherence to HAART was examined. Evaluations were conducted at baseline, 6 weeks, and 6 months for participants (n = 85) randomly assigned to either the intervention group or a comparison group; 69 (81%) remained in the study for the entire 6-month duration. The intervention group scored significantly better than the comparison group on 3 of 5 measures of HIV health literacy at 6 weeks and on 2 of 5 measures, at 6 months. While there was a weak trend for the intervention group to report an increase in self-efficacy of medication adherence management, baseline to 6 weeks, no other changes were significant. Perceptions of the quality of relationship and communications with their HIV-treating physicians improved both at 6 weeks (p = 0.04) and at 6 months (p < 0.001). The comparison group showed little change baseline to 6 weeks and baseline to 6 months. While there was a trend for the pilot group to report better medication adherence, these differences were not statistically significant. Further evaluation of the impact of this adherence enhancement program is needed.     

Cross‐sex shifts in two brain imaging phenotypes and their relation to polygenic scores for same‐sex sexual behavior: A study of 18,645 individuals from the UK Biobank

Genetic and hormonal factors have been suggested to influence human sexual orientation. Previous studied proposed brain differences related to sexual orientation and that these follow cross‐sex shifted patterns. However, the neurobiological correlates of sexual orientation and how genetic factors relate to brain structural variation remains largely unexplored. Using the largest neuroimaging‐genetics dataset available on same‐sex sexual behavior (SSB) (n = 18,645), we employed a data‐driven multivariate classification algorithm (PLS) on magnetic resonance imaging data from two imaging modalities to extract brain covariance patterns related to sex. Through analyses of latent variables, we tested for SSB‐related cross‐sex shifts in such patterns. Using genotype data, polygenic scores reflecting the genetic predisposition for SSB were computed and tested for associations with neuroimaging outcomes. Patterns important for classifying between males and females were less pronounced in non‐heterosexuals. Predominantly in non‐heterosexual females, multivariate brain patterns as represented by latent variables were shifted toward the opposite sex. Complementary univariate analyses revealed region specific SSB‐related differences in both males and females. Polygenic scores for SSB were associated with volume of lateral occipital and temporo‐occipital cortices. The present large‐scale study demonstrates multivariate neuroanatomical correlates of SSB, and tentatively suggests that genetic factors related to SSB may contribute to structural variation in certain brain structures. These findings support a neurobiological basis to the differences in human sexuality.