Integrated optical frequency division for microwave and mmWave generation.

The generation of ultra-low-noise microwave and mmWave in miniaturized, chip-based platforms can transform communication, radar and sensing systems1-3. Optical frequency division that leverages optical references and optical frequency combs has emerged as a powerful technique to generate microwaves with superior spectral purity than any other approaches4-7. Here we demonstrate a miniaturized optical frequency division system that can potentially transfer the approach to a complementary metal-oxide-semiconductor-compatible integrated photonic platform. Phase stability is provided by a large mode volume, planar-waveguide-based optical reference coil cavity8,9 and is divided down from optical to mmWave frequency by using soliton microcombs generated in a waveguide-coupled microresonator10-12. Besides achieving record-low phase noise for integrated photonic mmWave oscillators, these devices can be heterogeneously integrated with semiconductor lasers, amplifiers and photodiodes, holding the potential of large-volume, low-cost manufacturing for fundamental and mass-market applications13.

Integrated photonic molecule Brillouin laser with a high-power sub-100-mHz fundamental linewidth.

Photonic integrated lasers with an ultra-low fundamental linewidth and a high output power are important for precision atomic and quantum applications, high-capacity communications, and fiber sensing, yet wafer-scale solutions have remained elusive. Here we report an integrated stimulated Brillouin laser (SBL), based on a photonic molecule coupled resonator design, that achieves a sub-100-mHz fundamental linewidth with greater than 10-mW output power in the C band, fabricated on a 200-mm silicon nitride (Si3N4) CMOS-foundry compatible wafer-scale platform. The photonic molecule design is used to suppress the second-order Stokes (S2) emission, allowing the primary lasing mode to increase with the pump power without phase noise feedback from higher Stokes orders. The nested waveguide resonators have a 184 million intrinsic and 92 million loaded Q, over an order of magnitude improvement over prior photonic molecules, enabling precision resonance splitting of 198 MHz at the S2 frequency. We demonstrate S2-suppressed single-mode SBL with a minimum fundamental linewidth of 71±18 mHz, corresponding to a 23±6-mHz2/Hz white-frequency-noise floor, over an order of magnitude lower than prior integrated SBLs, with an ∼11-mW output power and 2.3-mW threshold power. The frequency noise reaches the resonator-intrinsic thermo-refractive noise from 2-kHz to 1-MHz offset. The laser phase noise reaches -155 dBc/Hz at 10-MHz offset. The performance of this chip-scale SBL shows promise not only to improve the reliability and reduce size and cost but also to enable new precision experiments that require the high-speed manipulation, control, and interrogation of atoms and qubits. Realization in the silicon nitride ultra-low loss platform is adaptable to a wide range of wavelengths from the visible to infrared and enables integration with other components for systems-on-chip solutions for a wide range of precision scientific and engineering applications including quantum sensing, gravitometers, atom interferometers, precision metrology, optical atomic clocks, and ultra-low noise microwave generation.

Ultralow 0.034†dB/m loss wafer-scale integrated photonics realizing 720 million Q and 380 µW threshold Brillouin lasing.

We demonstrate 0.034 dB/m loss waveguides in a 200-mm wafer-scale, silicon nitride (Si3N4) CMOS-foundry-compatible integration platform. We fabricate resonators that measure up to a 720 million intrinsic Q resonator at 1615 nm wavelength with a 258 kHz intrinsic linewidth. This resonator is used to realize a Brillouin laser with an energy-efficient 380 µW threshold power. The performance is achieved by reducing scattering losses through a combination of single-mode TM waveguide design and an etched blanket-layer low-pressure chemical vapor deposition (LPCVD) 80 nm Si3N4 waveguide core combined with thermal oxide lower and tetraethoxysilane plasma-enhanced chemical vapor deposition (TEOS-PECVD) upper oxide cladding. This level of performance will enable photon preservation and energy-efficient generation of the spectrally pure light needed for photonic integration of a wide range of future precision scientific applications, including quantum, precision metrology, and optical atomic clocks.

422 Million intrinsic quality factor planar integrated all-waveguide resonator with sub-MHz linewidth.

High quality-factor (Q) optical resonators are a key component for ultra-narrow linewidth lasers, frequency stabilization, precision spectroscopy and quantum applications. Integration in a photonic waveguide platform is key to reducing cost, size, power and sensitivity to environmental disturbances. However, to date, the Q of all-waveguide resonators has been relegated to below 260 Million. Here, we report a Si3N4 resonator with 422 Million intrinsic and 3.4 Billion absorption-limited Qs. The resonator has 453 kHz intrinsic, 906 kHz loaded, and 57 kHz absorption-limited linewidths and the corresponding 0.060 dB m-1 loss is the lowest reported to date for waveguides with deposited oxide upper cladding. These results are achieved through a careful reduction of scattering and absorption losses that we simulate, quantify and correlate to measurements. This advancement in waveguide resonator technology paves the way to all-waveguide Billion Q cavities for applications including nonlinear optics, atomic clocks, quantum photonics and high-capacity fiber communications.

Measurement-based care: Use of the Beck Anxiety Inventory (BAI) in a veteran population.

The Beck Anxiety Inventory (BAI) is widely used within the Veterans Health Administration (VHA), both as an assessment tool and as a part of measurement-based care practices. However, there is preliminary evidence that the BAI may perform uniquely in veteran samples, emphasizing the need for a comprehensive investigation of the BAI in this population. The present study compared the normative data reported by Beck and Steer (1993) to secondary data generated by a nationwide sample of U.S. military veterans receiving treatment through the VHA. Secondary data, including initial BAI scores, demographic characteristics, treatment location, and diagnoses originally recorded during the course of usual VHA care over a 5-year period for 57,088 individual veterans, were extracted through the VA Informatics and Computing Infrastructure. BAI scores were compared across samples and various veteran subgroups. Exploratory and confirmatory factor analyses were also conducted. Results revealed that the BAI performed similarly across veteran and normative samples. Male and older veterans were found to have lower BAI scores than their respective counterparts. Factor analyses indicated that a three-factor model best fit the veteran data. Additionally, a cut score of 18 best differentiated between veterans with and without anxiety and related disorders. This study helps support the use of the BAI as a reliable and valid instrument for assessing anxiety symptoms in veterans. Additional research is recommended to better guide BAI interpretation across age groups and sexes/genders. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Venoarterial ECMO for Adults: JACC Scientific Expert Panel.

Venoarterial extracorporeal membrane oxygenation (ECMO) is a rescue therapy that can stabilize patients with hemodynamic compromise, with or without respiratory failure, for days or weeks. In cardiology, the main indications for ECMO include cardiac arrest, cardiogenic shock, post-cardiotomy shock, refractory ventricular tachycardia, and acute management of complications of invasive procedures. The fundamental premise underlying ECMO is that it is a bridge-to recovery, to a more durable bridge, to definitive treatment, or to decision. As a very resource- and effort-intensive intervention, ECMO should not be used on unsalvageable patients. As the use of this technology continues to evolve rapidly, it is important to understand the indications and contraindications; the logistics of ECMO initiation, management, and weaning; the general infrastructure of the program (including the challenges associated with transferring patients supported by ECMO); and ethical considerations, areas of uncertainty, and future directions.

Daily Drinking Is Associated with Increased Mortality.

BACKGROUND: There is evidence that low-level alcohol use, drinking 1 to 2 drinks on occasion, is protective for cardiovascular disease, but increases the risk of cancer. Synthesizing the overall impact of low-level alcohol use on health is therefore complex. The objective of this paper was to examine the association between frequency of low-level drinking and mortality. METHODS: Two data sets with self-reported alcohol use and mortality follow-up were analyzed: 340,668 individuals from the National Health Interview Survey (NHIS) and 93,653 individuals from the Veterans Health Administration (VA) outpatient medical records. Survival analyses were conducted to evaluate the association between low-level drinking frequency and mortality. RESULTS: The minimum risk drinking frequency among those who drink 1 to 2 drinks per occasion was found to be 3.2 times weekly in the NHIS data, based on a continuous measure of drinking frequency, and 2 to 3 times weekly in the VA data. Relative to these individuals with minimum risk, individuals who drink 7 times weekly had an adjusted hazard ratio (HR) of all-cause mortality of 1.23 (p < 0.0001) in the NHIS data, and individuals who drink 4 to 7 times weekly in the VA data also had an adjusted HR of 1.23 (p = 0.01). Secondary analyses in the NHIS data showed that the minimum risk was drinking 4 times weekly for cardiovascular mortality, and drinking monthly or less for cancer mortality. The associations were consistent in stratified analyses of men, women, and never smokers. CONCLUSIONS: The minimum risk of low-level drinking frequency for all-cause mortality appears to be approximately 3 occasions weekly. The robustness of this finding is highlighted in 2 distinctly different data sets: a large epidemiological data set and a data set of veterans sampled from an outpatient clinic. Daily drinking, even at low levels, is detrimental to one's health.

Digital Breast Tomosynthesis: Cost-Effectiveness of Using Private and Medicare Insurance in Community-Based Health Care Facilities.

OBJECTIVE: The purpose of this study was to determine whether digital breast tomosynthesis (DBT) is a cost-effective alternative to full-field digital mammography (FFDM) for both Medicare and privately insured patients undergoing screening mammography. MATERIALS AND METHODS: A retrospective data analysis was performed between July 15, 2013, and July 14, 2014, with data on women presenting for screening mammography that included any additional radiologic workup (n = 6319). Patients chose to undergo DBT or FFDM on the basis of personal preference, physician suggestion, and cost difference. The summation of findings over the 1-year period were used to calculate recall rates, cancer detection rates, and billing costs for a regional private insurer and Medicare. RESULTS: Data from the 6319 patients who participated were divided: 3655 patients underwent DBT, and 2664 underwent FFDM during the year of screening. Private insurance billing cost $2.9 million, and Medicare cost $1.2 million for screening, follow-up imaging, and radiologic procedures. Per-person costs were approximately $40 higher for the DBT group using both forms of insurance. However, cost per cancer detected was lower in the DBT group for both private and governmental insurance, leading to potentially $3.7 million and $899,000 saved per 100 cancers found. After standardization of the difference in cancer detection rates between the two groups, DBT was a cost-equivalent alternative to FFDM for private insurance billing but was a cost-inefficient alternative with respect to Medicare costs. CONCLUSION: In a community-based setting, DBT is a cost-equivalent or potentially cost-effective alternative to FFDM and has the capacity for improving cancer detection and recall rates.

Noncompetitive and Competitive Adsorption of Heavy Metals in Sulfur-Functionalized Ordered Mesoporous Carbon.

In this work, sulfur-functionalized ordered mesoporous carbons were synthesized by activating the soft-templated mesoporous carbons with sulfur bearing salts that simultaneously enhanced the surface area and introduced sulfur functionalities onto the parent carbon surface. XPS analysis showed that sulfur content within the mesoporous carbons were between 8.2% and 12.9%. The sulfur functionalities include C-S, C═S, -COS, and SOx. SEM images confirmed the ordered mesoporosity within the material. The BET surface areas of the sulfur-functionalized ordered mesoporous carbons range from 837 to 2865 m2/g with total pore volume of 0.71-2.3 cm3/g. The carbon with highest sulfur functionality was examined for aqueous phase adsorption of mercury (as HgCl2), lead (as Pb(NO3)2), cadmium (as CdCl2), and nickel (as NiCl2) ions in both noncompetitive and competitive mode. Under noncompetitive mode and at a pH greater than 7.0 the affinity of sulfur-functionalized carbons toward heavy metals were in the order of Hg > Pb > Cd > Ni. At lower pH, the adsorbent switched its affinity between Pb and Cd. In the noncompetitive mode, Hg and Pb adsorption showed a strong pH dependency whereas Cd and Ni adsorption did not demonstrate a significant influence of pH. The distribution coefficient for noncompetitive adsorption was in the range of 2448-4000 mL/g for Hg, 290-1990 mL/g for Pb, 550-560 mL/g for Cd, and 115-147 for Ni. The kinetics of adsorption suggested a pseudo-second-order model fits better than other models for all the metals. XPS analysis of metal-adsorption carbons suggested that 7-8% of the adsorbed Hg was converted to HgSO4, 14% and 2% of Pb was converted to PbSO4 and PbS/PbO, respectively, and 5% Cd was converted to CdSO4. Ni was below the detection limit for XPS. Overall results suggested these carbon materials might be useful for the separation of heavy metals.

Examining the performance of the brief addiction monitor.

The Center for Excellence in Drug Abuse Treatment and Education (Center for Excellence in Substance Abuse Treatment and Education (CESATE; 2010). Brief Addiction Monitor: Manual of Operations. Philadelphia, PA) recently suggested that Veterans Affairs' (VA) addictions treatment programs, in order to encourage measurement based care, begin using a new measure of substance abuse, the Brief Addictions Monitor (BAM). To date, only one study Caccolia et al, 2013. Development and initial evaluation of the Brief Addiction Monitor (BAM). Journal of Substance Abuse Treatment, 44, 256-63. doi: http://dx.doi.org/10.1016/j.jsat.2012.07.013) has examined the psychometric properties of a version of this instrument. However, this study did not use the version of the BAM currently available to most VA providers via the mental health assistant software; rather, the authors reported the properties of a BAM where most of the items had continuous (or near continuous) response options. The current study seeks to provide data on the version of the BAM which uses 5 point Likert scale response options for its questions, the version available on the mental health assistant software. Based on data from more than 700 veterans enrolled in out-patient (OP) and in-patient (IP) addictions treatment programs, this study examined the factor structure, reliability, and validity of this version of the BAM. Across both groups, results suggested that the BAM lacked a reliable factor structure, in contrast to the findings from the earlier study. However, a single scale, composed of a minority of items on the BAM, showed promise. A minority of the items (five) provided valid information across both OP and IP samples when applied individually, as indicated by convergent and divergent validity comparisons with other measures of functioning; tracking changes in functioning over the course of treatment; and correlating with changes in convergent and divergent validity measures. This partially supported the CESATE (CESATE; 2010). Brief Addiction Monitor: Manual of Operations. Philadelphia, PA) call to use the individual BAM items. Overall, results suggested that changing the structure of the response options may have had a negative impact on the psychometric properties of the BAM.

Endometrial ablation: is tubal ligation a risk factor for hysterectomy.

STUDY OBJECTIVE: To determine whether tubal ligation is a risk factor for future hysterectomy after second-generation endometrial ablation. DESIGN: Retrospective chart review (Canadian Task Force classification II-3). SETTING: Resident-run clinic and private office in a community setting. PATIENTS: Five hundred eighty-seven patients who underwent endometrial ablation. INTERVENTIONS: Patients underwent endometrial ablation using either radiofrequency or thermal balloon. Data collected included age, body mass index, uterine length, and endometrial stripe, as well as smoking status and presence or absence of hypertension and hypothyroidism. Indication for hysterectomy and pathologic findings at hysterectomy were also examined. MEASUREMENTS AND MAIN RESULTS: There was no association between tubal ligation and second-generation endometrial ablation resulting in hysterectomy (p = .09). Statistically significant variables included endometrial stripe (p <.001) and smoking (p <.001). There was no statistical significance between the groups insofar as type of ablation, age, body mass index, uterine length, hypertension, or hypothyroidism. Time from endometrial ablation to hysterectomy between groups was not significant. Indication for hysterectomy and pathologic findings after hysterectomy were also not significant. CONCLUSIONS: Tubal ligation is not a statistically significant risk factor for hysterectomy after endometrial ablation. Tubal ligation does not affect the length of time from endometrial ablation to hysterectomy.

Metoclopramide to augment lactation, does it work? A randomized trial.

OBJECTIVES: The objective of this study was to investigate the efficacy of metoclopramide on augmentation of milk production in mothers of premature newborns. METHODS: This was a randomized, double-blind, placebo-controlled trial. Women who delivered at ≤34 weeks of gestation, with no prior breastfeeding experience, singleton pregnancy, and no contraindications to using metoclopramide were eligible for entry. Twenty-five women were randomly assigned to receive 10 mg of metoclopramide or placebo three times daily for 8 days starting within 36 h of birth. Certified lactation nurses provided breastfeeding education. Breast milk expressed at each pumping session over the 8 days of treatment was recorded. RESULTS: Data from 18 patients were available for analysis. Milk production in both groups increased rapidly during the first 4 days and then more gradually to an average for the last 4 days of 633 ± 168 (9) ml/day [mean ± SEM (n)] for the placebo group and 459 ± 91 (10) ml/day for the metoclopramide group. Analysis with a repeated-measures ANOVA indicated a significant increase in milk production during the 8-day measurement period [within subjects p < 0.001]; however, there was no significant difference in milk production between the two groups [between subjects p = 0.427]. Side effects were similar between groups. CONCLUSION: In mothers with preterm babies, metoclopramide treatment does not augment (sample size had 80% power for detection of 50% difference) the breast milk production. Maternal interest, education, and support are recognized as mainstay in accomplishing successful lactation.

Inflammatory bowel disease and coronary artery disease.

Chronic inflammation with the presence of excess serum acute-phase proteins, cytokines and cell adhesion molecules is increasingly being implicated in atherosclerosis. The association between inflammatory bowel disease (IBD) and coronary artery disease (CAD) is unstudied. This is a preliminary, thesis-generating cross-sectional study aimed at evaluating the presence of traditional atherosclerotic risk factors in patients with IBD and CAD compared with the control population. The medical records of 42 consecutive IBD patients with CAD from 1999 to 2005 (27 men) were reviewed for the Framingham risk factors. The Framingham risk score (FRS) is calculated based on age, sex, hypertension, diabetes and hyperlipidemia. FRS of patients with IBD and CAD was compared with the FRS of 137 age- and sex-matched (102 men) consecutive patients with CAD (controls). When the Framingham risk score adjusted for group and gender with age as a covariate, the adjusted total FRS score was higher in patients with CAD alone (10.0 [3.75]) as compared to those with; IBD and CAD: (8.1 [3.47]; p = 0.001). FRS is lower in cases (patients with IBD and CAD) when compared with the controls (CAD alone).

Outcome of noncardiac surgery in patients with ventricular assist devices.

An increasing number of patients are living with ventricular assist devices (VADs). Many of these patients will require noncardiac surgery for conditions not directly related to their VADs. The aim of this study was to assess the risks and outcomes of noncardiac surgery in these patients. Perioperative and follow-up data from patients with VADs who underwent noncardiac surgery from 1993 to 2006 were analyzed. In that period, 184 VADs were implanted in 155 patients. Thirty-seven patients (24%) subsequently underwent 59 noncardiac surgeries. The mean duration of VAD support before surgery was 229 days. Bleeding was the most common postsurgical complication (10%), necessitating reexploration in 20% of abdominal surgeries. Thirty-day mortality was 12%. No deaths were caused by direct complications of surgery. Successful transplantation occurred in 72% of bridge to transplantation patients who required noncardiac surgery, compared with 71% of these patients who did not require noncardiac surgery (relative risk 1.0, p = 0.9). The average duration of VAD support after noncardiac surgery for destination therapy patients was 324 days, most of which time was spent at home. In conclusion, outcomes after noncardiac surgery in patients with VADs are favorable, and most patients continue to benefit from the intended purpose of mechanical circulatory support after recovering from noncardiac surgery.

Improving outcomes with long-term "destination" therapy using left ventricular assist devices.

OBJECTIVE: Destination therapy experience using long-term left ventricular assist devices was analyzed relative to the benchmark Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure trial to evaluate the potential for improving outcomes with this groundbreaking therapy for advanced heart failure. METHODS: The largest single-center experience with destination therapy in the United States (Utah Artificial Heart Program, LDS Hospital, Salt Lake City, UT) was retrospectively analyzed. All destination therapy recipients (n = 23) presented with chronic, advanced heart failure, meeting indications for destination therapy adopted from the Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure trial. All received HeartMate left ventricular assist devices (Thoratec Corp, Pleasanton, Calif), with 87% receiving an improved XVE model. Advanced practice guidelines were implemented using a multidisciplinary approach. Survivals (Kaplan-Meier, log-rank analyses) and adverse events (Poisson regression) were compared with those of the Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure left ventricular assist device group (n = 68). RESULTS: Survival in the destination therapy group was significantly increased (P = .007), with an overall reduction in mortality of 66%. The 2-year survival was 77% for destination therapy compared with 29% for the Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure left ventricular assist device group (P < .0001). The 1-year survival was 77% for destination therapy compared with the Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure left ventricular assist device rate of 52% (P = .036). Adverse events decreased by 38% (3.90 per patient-year in the destination therapy group compared with the Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure left ventricular assist device rate of 6.32). Factors related to severity of illness met Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure-like criteria for both groups. CONCLUSIONS: This analysis provides evidence that long-term destination therapy can be improved well beyond the pioneering experience of the Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure trial. With continued evolution of devices, management, and patient selection, outcomes approaching those of heart transplantation may be possible.

Evaluation of a Shortened South Oaks Gambling Screen in veterans with addictions.

Rates of pathological gambling have increased with the availability of legalized gambling. Substance-abuse units increasingly recognize the need to assess for gambling problems. The South Oaks Gambling Screen (SOGS; H. R. Lesieur & S. B. Blume, 1987) has filled this need. Previous research (M. Oehlert & K. Nelson, 2004) has considered the feasibility of reducing the length of the SOGS while maintaining its ability to identify people at risk for problematic gambling. In this study, the authors examined the utility of a shortened SOGS (SSOGS) in a 2nd sample of veterans with addictions. The authors used data analysis to explore SSOGS psychometric properties and to provide additional support for use of the shorter instrument.

The role of continuous fetal monitoring in the management of preterm premature rupture of membranes.

OBJECTIVE: Continuous fetal monitoring (CFM) is often used in the management of preterm premature rupture of membranes (PPROM) but there is little evidence to support this approach. The objective of this study was to evaluate the clinical outcome of PPROM when managed by CFM. METHODS: A retrospective review was conducted of 129 cases PPROM outcomes for the period January 1, 1998 to December 31, 2003. All women underwent CFM. Delivery was carried out for non-reassuring fetal testing, vaginal bleeding, evidence of infection, positive vaginal pool phosphatidylglycerol when available, and spontaneous labor. RESULTS: Delivery was carried out because of an abnormal fetal heart tracing in 15 women (11.7%). The mean gestational age at admission was 32.2 weeks (95% CI 31.7-32.7), the mean gestational age at delivery was 32.7 weeks (95% CI 32.2-33.1), and the mean latency period was 3.3 days (95% CI 1.5-5.0). Gestational age at rupture of membranes was inversely correlated with latency period (n = 128, r = -0.372, p < 0.001). With regard to gestational age, gravidity, and latency period there was no significant difference noted with respect to why the subjects delivered. No intrauterine deaths occurred in the study. CONCLUSION: In our series, fetal heart rate tracing abnormalities were the indication for delivery in a small but significant percentage of conservatively managed PPROM cases. Our review suggests that a prospective trial of CFM versus intermittent monitoring techniques should be carried out.

Prevalence and risks of allosensitization in HeartMate left ventricular assist device recipients: the impact of leukofiltered cellular blood product transfusions.

OBJECTIVE: Allosensitization of left ventricular assist device recipients has been associated with perioperative transfusion of cellular blood products. The relative sensitizing contribution of leukofiltered cellular blood products, however, remains unclear. We investigated the pattern of sensitization in left ventricular assist device recipients in relation to cellular blood product transfusions received. METHODS: Seventy-one consecutive nonsensitized recipients of the HeartMate left ventricular assist device (Thoratec Corporation, Pleasanton, Calif) as a bridge to transplantation were reviewed. Panel-reactive HLA antibody levels at consecutive times after device implantation were correlated with perioperative cellular blood product transfusions. RESULTS: Fifty-four patients received leukofiltered cellular blood products (transfused), whereas 17 patients received only fresh-frozen plasma (nontransfused). Among nontransfused patients, 58.8% (10/17) became sensitized during mechanical support, versus 35.2% of transfused patients (19/54, P = .15). There was a trend toward more sensitization during the 12 weeks after device placement in nontransfused patients. Kaplan-Meier analysis revealed significantly more sensitization in nontransfused patients than in transfused patients, despite equal rates of transplantation (P = .05). A dose-response analysis revealed significant trends toward less sensitization and lower peak panel-reactive antibody level with more cellular blood product transfusions (P = .04). Multivariate Cox regression revealed only increasing transfusions to be associated with a reduced risk of sensitization (hazard ratio 0.18, P = .01). CONCLUSIONS: Sensitization becomes more prevalent with increasing length of support. Avoidance of perioperative leukocyte-filtered cellular blood product transfusions does not decrease the incidence or degree of HLA sensitization. Conversely, cellular blood product transfusions may be associated with lessened alloimmunization and may mitigate the sensitization seen in recipients of the HeartMate left ventricular assist device as a bridge to transplantation.

The effect of a 12-month longitudinal long-term care rotation on knowledge and attitudes of internal medicine residents about geriatrics.

OBJECTIVE: To determine if participation in a 12-month longitudinal long-term care (LTC) rotation resulted in improved knowledge and attitudes about geriatrics. DESIGN: Longitudinal study with paired measurements. SETTING: A community LTC facility and a university-affiliated, community-based internal medicine residency program. PARTICIPANTS: Sixty-seven internal medicine residents who participated in the rotation from 1997 through 2004. INTERVENTION: The internal medicine residents attended nursing home (NH) rounds one half day per month for 1 year, during which time they participated in a case-based interactive lecture on a core geriatric topic and rounded on their assigned patients. MEASUREMENTS: Knowledge was assessed using a 70-item test. Attitudes were evaluated with a 28-item, 5-point Likert scale (1 = least positive, 5 = most positive). RESULTS: The percent correct responses on geriatric knowledge pretest was 47% (95% CI = 45.2% to 48.8%) and on the posttest it was 57.5% (95% CI = 55.3% to 59.6%) (t = 8.180, df = 67, P < .001). The pretest total attitude score was 3.6 (95% CI = 3.6 to 3.7), with a posttest score of 3.7 (95% CI = 3.7 to 3.8) (P < .001). The difference in this total was accounted for mainly by the significant changes in the attitude subscales in educational preparation (pretest 3.6 [95% CI = 3.5 to 3.8]; posttest 3.8 [95% CI = 3.7 to 3.9] [P < .001]), general attitudes (pretest 4.0 [95% CI = 3.9 to 4.1]; posttest 4.2 [95% CI = 4.0 to 4.3] [P = .006]), and therapeutic potential (pretest 3.7 [95% CI = 3.5 to 3.8]; posttest 3.8 [95% CI = 3.7 to 3.9] [P = .048]). CONCLUSION: A longitudinal LTC rotation is an efficient and effective way to systematically provide internal medicine residents their core knowledge and experience in geriatrics.