Optimization of heterotrophic cultivation of Chlorella sp. HS2 using screening, statistical assessment, and validation.

The heterotrophic cultivation of microalgae has a number of notable advantages, which include allowing high culture density levels as well as enabling the production of biomass in consistent and predictable quantities. In this study, the full potential of Chlorella sp. HS2 is explored through optimization of the parameters for its heterotrophic cultivation. First, carbon and nitrogen sources were screened in PhotobioBox. Initial screening using the Plackett-Burman design (PBD) was then adopted and the concentrations of the major nutrients (glucose, sodium nitrate, and dipotassium phosphate) were optimized via response surface methodology (RSM) with a central composite design (CCD). Upon validation of the model via flask-scale cultivation, the optimized BG11 medium was found to result in a three-fold improvement in biomass amounts, from 5.85 to 18.13 g/L, in comparison to a non-optimized BG11 medium containing 72 g/L glucose. Scaling up the cultivation to a 5-L fermenter resulted in a greatly improved biomass concentration of 35.3 g/L owing to more efficient oxygenation of the culture. In addition, phosphorus feeding fermentation was employed in an effort to address early depletion of phosphate, and a maximum biomass concentration of 42.95 g/L was achieved, with biomass productivity of 5.37 g/L/D.

Radial haemostasis is facilitated with a potassium ferrate haemostatic patch: the Statseal with TR Band assessment trial (STAT).

AIMS: Haemostasis is a limiting factor for discharge after uncomplicated transradial procedures. The purpose of this study was to determine whether a potassium ferrate haemostatic patch (PFHP) could serve as an adjunct to the air-bladder TR Band (TRB) to facilitate implementation of a rapid deflation protocol. METHODS AND RESULTS: This was a prospective multicentre randomised controlled trial comparing radial haemostatic protocols. Deflation of the TRB was attempted at 40 minutes with PFHP and at 120 minutes without the PFHP. The primary outcome was time to full deflation of the TRB with haemostasis. At four US sites, 180 patients were enrolled after receiving a minimum of 5,000 units of unfractionated heparin or bivalirudin. Interventions comprised 30% of procedures. Successful TRB deflation occurred at 43±14 minutes with PFHP and 160±43 minutes without PFHP (p<0.001). Minor haematomas occurred in nine (10.3%) of the TRB patients and 16 (17.2%) of the PFHP patients (p=0.20). Radial artery occlusion occurred in 2% of patients in the PFHP group (p=NS). Outpatients randomised to PFHP were discharged 51±83.5 minutes earlier than control. CONCLUSIONS: The PFHP haemostatic patch facilitated early deflation of the TRB with a non-significant increase in forearm haematomas. Use of the PFHP may improve patient throughput and allow earlier discharge following transradial procedures.

Improved costs and outcomes with conscious sedation vs general anesthesia in TAVR patients: Time to wake up?

BACKGROUND: Transcatheter aortic valve replacement (TAVR) has become a commonplace procedure for the treatment of aortic stenosis in higher risk surgical patients. With the high cost and steadily increasing number of patients receiving TAVR, emphasis has been placed on optimizing outcomes as well as resource utilization. Recently, studies have demonstrated the feasibility of conscious sedation in lieu of general anesthesia for TAVR. This study aimed to investigate the clinical as well as cost outcomes associated with conscious sedation in comparison to general anesthesia in TAVR. METHODS: Records for all adult patients undergoing TAVR at our institution between August 2012 and June 2016 were included using our institutional Society of Thoracic Surgeons (STS) and American College of Cardiology (ACC) registries. Cost data was gathered using the BIOME database. Patients were stratified into two groups according to whether they received general anesthesia (GA) or conscious sedation (CS) during the procedure. No-replacement propensity score matching was done using the validated STS predicted risk of mortality (PROM) as a propensity score. Primary outcome measure with survival to discharge and several secondary outcome measures were also included in analysis. According to our institution's data reporting guidelines, all cost data is presented as a percentage of the general anesthesia control group cost. RESULTS: Of the 231 patients initially identified, 225 (157 GA, 68 CS) were included for analysis. After no-replacement propensity score matching, 196 patients (147 GA, 49 CS) remained. Overall mortality was 1.5% in the matched population with a trend towards lower mortality in the CS group. Conscious sedation was associated with significantly fewer ICU hours (30 vs 96 hours, p = <0.001) and total hospital days (4.9 vs 10.4, p<0.001). Additionally, there was a 28% decrease in direct cost (p<0.001) as well as significant decreases in all individual all cost categories associated with the use of conscious sedation. There was no difference in composite major adverse events between groups. These trends remained on all subsequent subgroup analyses. CONCLUSION: Conscious sedation is emerging as a safe and viable option for anesthesia in patients undergoing transcatheter aortic valve replacement. The use of conscious sedation was not only associated with similar rates of adverse events, but also shortened ICU and overall hospital stays. Finally, there were significant decreases in all cost categories when compared to a propensity matched cohort receiving general anesthesia.

Importance of electrocardiography in the assessment and management of heart failure: a case report.

Restoring and maintaining optimal electrical activation of the cardiac chambers as well as atrioventricular synchrony are important aspects of heart failure management. The 12-lead electrocardiogram remains a simple and cost-effective diagnostic tool that can provide important clues in achieving this goal. We report a case where careful interpretation of the 12-lead electrocardiogram led to the diagnosis of pacemaker syndrome. This recognition led to a therapeutic intervention that resulted in the resolution of the patient's heart failure symptoms. The importance of electrocardiography and atrioventricular synchrony in the management of heart failure will also be discussed.