Temporal evolution of the biological response to laser-induced refractive index change (LIRIC) in rabbit corneas.

Laser-induced refractive index change (LIRIC) is a new, non-incisional, non-ablative, femtosecond photo-modification technique being developed for vision correction in humans. Prior, exvivo studies showed intra-tissue refractive index change to induce minimal cell death, restricted to the laser focal zone in the corneal stroma, and with no observable damage to the epithelium or endothelium. Here, we used live rabbits to ascertain longer-term consequences of LIRIC in vivo. Specifically, we assessed cell death, fibrosis, corneal nerve distribution, endothelial cell density, and corneal structure for up to 3 months after LIRIC. A +2.5 D gradient-index LIRIC Fresnel lens was inscribed inside 20 applanated corneas of Dutch Belted rabbits, over a circular region of the mid-stroma measuring 4.5 mm in diameter. Twelve additional rabbit eyes were used as applanation-only controls to differentiate the effects of laser treatment and suction applanation on biological and structural parameters. In vivo optical measurements were performed pre-operatively, then immediately, 2, 4, and 12 weeks after the procedure, to measure endothelial cell density and changes in corneal structure. Groups of four rabbits were sacrificed at 4 hours, 2, 4, and 12 weeks after LIRIC for histological determinations; the TUNEL assay was used to evaluate cell death, H&E staining was used to assess inflammatory infiltration, and immunostaining for α-smooth muscle actin (α-SMA) and ßIII tubulin (Tuj-1) was performed to assess myofibroblast differentiation and corneal nerve distribution, respectively. Consistent with prior ex vivo data, only minimal cell death was observed in the laser focal zone, with TUNEL-positive cells restricted to the stromal region of refractive index change 4 h after LIRIC. No TUNEL-positive cells were evident anywhere in the cornea 2, 4, or 12 weeks after LIRIC. Applanation-only corneas were completely TUNEL-negative. Neither LIRIC-treated nor applanation-only eyes exhibited α-SMA-positive staining or altered corneal nerve distributions at any of the time points examined. In vivo confocal imaging revealed normal endothelial cell densities in all eyes (whether LIRIC-treated or applanation-only) at all time points. Optical coherence tomography showed suction applanation to cause a temporary decrease in central corneal thickness, which returned to normal within 4 h. Corneas into which LIRIC Fresnel lenses were written while applanated did not undergo major structural or shape changes beyond the temporary thinning already described for suction applanation. The present findings suggest that LIRIC patterns, which generated a clinically-relevant refractive correction in the mid-stromal region of live rabbit corneas, induced little-to-no disruption to corneal structure and biology for 3 months after the procedure. This affirms the relative safety of LIRIC and predicts that compared to traditional laser vision correction surgeries, common post-operative complications such as dry eye, haze, or patient discomfort may be entirely avoided.

Repeated head trauma is associated with smaller thalamic volumes and slower processing speed: the Professional Fighters' Brain Health Study.

OBJECTIVES: Cumulative head trauma may alter brain structure and function. We explored the relationship between exposure variables, cognition and MRI brain structural measures in a cohort of professional combatants. METHODS: 224 fighters (131 mixed martial arts fighters and 93 boxers) participating in the Professional Fighters Brain Health Study, a longitudinal cohort study of licensed professional combatants, were recruited, as were 22 controls. Each participant underwent computerised cognitive testing and volumetric brain MRI. Fighting history including years of fighting and fights per year was obtained from self-report and published records. Statistical analyses of the baseline evaluations were applied cross-sectionally to determine the relationship between fight exposure variables and volumes of the hippocampus, amygdala, thalamus, caudate, putamen. Moreover, the relationship between exposure and brain volumes with cognitive function was assessed. RESULTS: Increasing exposure to repetitive head trauma measured by number of professional fights, years of fighting, or a Fight Exposure Score (FES) was associated with lower brain volumes, particularly the thalamus and caudate. In addition, speed of processing decreased with decreased thalamic volumes and with increasing fight exposure. Higher scores on a FES used to reflect exposure to repetitive head trauma were associated with greater likelihood of having cognitive impairment. CONCLUSIONS: Greater exposure to repetitive head trauma is associated with lower brain volumes and lower processing speed in active professional fighters.

Invasive fungal infections following liver transplantation: incidence, risk factors, survival, and impact of fluconazole-resistant Candida parapsilosis (2003-2007).

Invasive fungal infections (IFIs) are associated with a high mortality rate for liver transplantation (LT) recipients. To study the incidence of and risk factors for IFIs in LT recipients and the associated mortality rates, we retrospectively reviewed the records of first-time deceased donor LT recipients (January 2003 to December 2007). The incidence of IFIs was 12%. Non-albicans Candida species accounted for 55% of IFIs; 50% of these IFIs were Candida parapsilosis. Only 43% of Candida isolates were fluconazole-susceptible (minimum inhibitory concentration ≤ 8 µ/mL). All C. parapsilosis isolates were fluconazole-resistant, and this coincided with a surge of these isolates during a peak period of LT. Factors associated with IFIs included a creatinine level > 2 mg/mL [hazard ratio (OR) = 2.4, 95% confidence interval (CI) = 1.2-5.0, P = 0.01], a Model for End-Stage Liver Disease score > 25 (OR = 2.4, 95% CI = 1.2-4.9, P = 0.02), pretransplant fungal colonization (OR = 7.0, 95% CI = 3.2-15.3, P < 0.001), and a daily prophylactic fluconazole dosage < 200 mg (OR = 2.8, 95% CI = 1.1-7.4, P = 0.03). According to a multivariate analysis, only pretransplant fungal colonization was associated with IFIs (OR = 7.8, 95% CI = 3.9-16.2, P < 0.001). The 1-year patient survival rates with and without IFIs were 41% and 80%, respectively, and the survival rates with C. parapsilosis, other non-albicans Candida, and Candida albicans IFIs were 28%, 50%, and 75%, respectively. In conclusion, IFIs after LT (especially non-albicans Candida species and fluconazole-resistant C. parapsilosis) were associated with reduced survival. The risk factors highlight the importance of pretransplant risk assessments. The identification of pretransplant fungal colonization may allow for risk modifications before or at the time of LT. Additionally, the number of LT procedures and prophylactic strategies may affect institutional outbreaks of resistant Candida strains.

Electronic Health Records and Pulmonary Function Data: Developing an Interoperability Roadmap. An Official American Thoracic Society Workshop Report.

A workshop "Electronic Health Records and Pulmonary Function Data: Developing an Interoperability Roadmap" was held at the American Thoracic Society 2019 International Conference. "Interoperability" is defined as is the ability of different information-technology systems and software applications to directly communicate, exchange data, and use the information that has been exchanged. At present, pulmonary function test (PFT) equipment is not required to be interoperable with other clinical data systems, including electronic health records (EHRs). For this workshop, we assembled a diverse group of experts and stakeholders, including representatives from patient-advocacy groups, adult and pediatric general and pulmonary medicine, informatics, government and healthcare organizations, pulmonary function laboratories, and EHR and PFT equipment and software companies. The participants were tasked with two overarching Aobjectives: 1) identifying the key obstacles to achieving interoperability of PFT systems and the EHR and 2) recommending solutions to the identified obstacles. Successful interoperability of PFT data with the EHR impacts the full scope of individual patient health and clinical care, population health, and research. The existing EHR-PFT device platforms lack sufficient data standardization to promote interoperability. Cost is a major obstacle to PFT-EHR interoperability, and incentives are insufficient to justify the needed investment. The current vendor-EHR system lacks sufficient flexibility, thereby impeding interoperability. To advance the goal of achieving interoperability, next steps include identifying and standardizing priority PFT data elements. To increase the motivation of stakeholders to invest in this effort, it is necessary to demonstrate the benefits of PFT interoperability across patient care and population health.

The Association Between Operating Room Personnel and Turnover With Surgical Site Infection in More Than 12 000 Neurosurgical Cases.

BACKGROUND: Surgical site infection (SSI) contributes significantly to postoperative morbidity and mortality and greatly increases the cost of care. OBJECTIVE: To identify the impact of workflow and personnel-related risk factors contributing to the incidence of SSIs in a large sample of neurological surgeries. METHODS: Data were obtained using an enterprisewide electronic health record system, operating room, and anesthesia records for neurological procedures conducted between January 1, 2009, and November 30, 2012. SSI data were obtained from prospective surveillance by infection preventionists using Centers for Disease Control and Prevention definitions. A multivariate model was constructed and refined using backward elimination logistic regression methods. RESULTS: The analysis included 12 528 procedures. Most cases were elective (94.5%), and the average procedure length was 4.8 hours. The average number of people present in the operating room at any time during the procedure was 10.0. The overall infection rate was 2.3%. Patient body mass index (odds ratio, 1.03; 95% confidence interval [CI], 1.01-1.04) and sex (odds ratio, 1.36; 95% CI, 1.07-1.72) as well as procedure length (odds ratio, 1.19 per additional hour; 95% CI, 1.15-1.23) and nursing staff turnovers (odds ratio, 1.095 per additional turnover; 95% CI, 1.02-1.21) were significantly correlated with the risk of SSI. CONCLUSION: This study found that patient body mass index and male sex were associated with an increased risk of SSI. Operating room personnel turnover, a modifiable, work flow-related factor, was an independent variable positively correlated with SSI. This study suggests that efforts to reduce operating room turnover may be effective in preventing SSI. ABBREVIATIONS: OR, operating roomSSI, surgical site infection.

Incidence and risk factors for 30-day readmission in patients undergoing nephrectomy procedures: a contemporary analysis of 5276 cases from the National Surgical Quality Improvement Program database.

OBJECTIVE: To explore factors associated with readmission after nephrectomy procedures using a large national database. MATERIALS AND METHODS: A national surgical outcomes database, the American College of Surgeon-National Surgical Quality Improvement Program registry, was queried for data on all patients undergoing open partial nephrectomy (OPN), minimally invasive (laparoscopic + robotic) partial nephrectomy (MIPN), and minimally invasive radical nephrectomy (MIRN) in 2011 and 2012. Patients undergoing these procedures were identified using the Current Procedural Terminology codes. The primary outcome was unplanned 30-day hospital readmission. A multivariate logistic regression model was constructed to assess for factors independently associated with the primary outcome. RESULTS: Overall, 5276 cases were identified and included in the analysis: 1411 OPN (26.7%), 2210 MIPN (41.8%), and 1655 MIRN (31.3%). Overall, the 30-day readmission rate was 5.9% (7.8% for OPN, 4.5% for MIPN, and 6.1% for MIRN). On multivariate analysis, the odds for 30-day readmission for MIPN was approximately 70% that of OPN (P = .012). The odds for 30-day readmission for 2012 was about 80% of that of 2011 (P <.001). History of steroid use and of bleeding disorder and occurrence of postoperative transfusion increase the odds of readmission by approximately 2 (P = .005, P = .038, and P <.001, respectively). A postoperative urinary infection increased the odds of readmission by 5.5 (P <.001). CONCLUSION: Contemporary 30-day readmission rates after nephrectomy procedures are influenced by specific patients' characteristics as well as postoperative adverse events. Moreover, contemporary MIPN seems to carry lower odds of readmission than OPN. It remains to be determined to what extent these findings are influenced by the expanding role of robotic technology.