Spin-up conversion, exchange-interactions, and tailored magnetic properties in core-shell La2NiMnO6of small crystallites

La₂NiMnO₆-a ferromagnetic (FM) insulator offers tunable charge carriers and spins useful to devise its multiple properties and applications. In this view, we studied a core-shell La₂NiMnO₆(2-3 nm shell on 65 - 80 nm core) of a Ni²⁺/Ni³⁺(d⁷) to Mn⁴⁺/Mn³⁺(d⁴) spin-up conversion- revived a new FM phase-2, raising a spin-densityσ_s = 0.7 s a^-1over the Ni^2+/Mn⁴⁺species (phase-1),σ_s = 0.5 s a^-1, i.e. 2.12μ_B/f.u. larger spin moment. HRTEM images studied with x-ray diffraction characterizing core-shell structure that plays a crucial role in tuning the high spin FM phase-2 of profound properties. Below 110 K, the dc magnetization and ac magnetic susceptibilityχ(ω,T) reveal a metastable magnetic behavior on an antiferromagnetic canting of a spin-glass nature. The results follow a Vogel-Fulcher type relaxation with a relaxation timeτ₀∼ 10^-13s, confirming a spin-glass freezing behavior. Uniquely, FM field of phase-1 controls magnetics of phase 2 of a coupled magnet, modulating joint features with small thermal magnetic hysteresis on heating-cooling cycles.

Quantification of Right Atrial-Indexed End-Systolic Volumes and Emptying Fraction in Children Undergoing Cardiac Surgery With Two-Dimensional Transesophageal Echocardiography: A Prospective Observational Study

OBJECTIVES

The primary objective of this study was to establish "normal" right atrial (RA)-indexed end-systolic volumes (ESVs) and emptying fraction (EF) in children undergoing ventricular septal defect (VSD) repair using two-dimensional (2D) transesophageal echocardiography (TEE). Secondary objectives were to obtain RA-indexed ESV and EF in children with RA/right ventricular (RV) volume overload (atrial septal defect [ASD]) and RV pressure overload (tetralogy of Fallot [TOF]) and to determine whether baseline differences existed in these indices among the three lesions.

DESIGN

A prospective observational study.

SETTING

Tertiary referral center and a university level teaching hospital.

PARTICIPANTS

The study comprised 90 children (30 in each cohort) >3 kg and <14 years old admitted for elective repair of either VSD, TOF, or ASD.

MEASUREMENTS AND MAIN RESULTS

RA ESV and EF were measured in the midesophageal four-chamber view using the area-length and the modified Simpson's methods with 2D TEE in the prebypass period. Mean RA- indexed ESV (area-length method) in the VSD cohort was 24.2 ± 6.7 mL/m², whereas it was significantly greater in the TOF (31.9 ± 9.8 mL/m²; p = 0.0008) and ASD (52 ± 12.9 mL/m²; p < 0.0001) cohorts. RA EF in the TOF cohort was 48.4% ± 7.6%, which was significantly more than in the VSD (41.5% ± 11.8%; p = 0.0093) and ASD (39.1% ± 12.3%; p = 0.0008) cohorts.

CONCLUSIONS

This was the first study using 2D TEE to measure RA indices in children with and without right-sided heart dilation undergoing cardiac surgery. In this study, RA, ESV, and EF were considerably different in children with congenital heart disease causing RV pressure or volume overload. Additional studies can examine how these values can be used for risk stratification in this cohort of patients or how they correlate with measures of ventricular performances.

Single collateral artery from descending thoracic aorta supplying pulmonary circulation-Computed tomography and echocardiographic images

Pulmonary atresia (PA) with ventricular septal defect (VSD) is a rare congenital cardiac anomaly in which the pulmonary blood flow is supplied by major aorta pulmonary collateral arteries (MAPCAs). The complete repair includes unifocalization of MAPCAs, closure of VSD, and placement of a right ventricle-to-pulmonary artery conduit. We report a case of VSD with PA, where the computed tomography and echocardiography images described a large single collateral artery arising from descending thoracic aorta dividing into left and right branches and supplying the entire pulmonary circulation.

Transesophageal echocardiography guided optimal positioning of central venous catheter tip in superior vena cava during surgical repair of sinus venosus atrial septal defect

Positioning of central venous catheter (CVC) tip in the intrathoracic portion of superior vena cava (SVC) is essential during the surgical repair of superior sinus venous atrial septal defects (SVASD). Although tracheal carina is described as a radiological landmark for positioning the tip of CVCs, it may not be successful at all times. We describe a case of SVC type SVASD, where the SVC-right pulmonary artery crossing point imaged on transesophageal echocardiography was used as an echocardiographic landmark for optimal positioning of the CVC tip.

Extracardiac Intrapericardial Mass Impersonating as Left Atrial Mass: Echocardiographic Perspectives

Extracardiac intrapericardial masses arising posterior to left atrium (LA) often mimic an intracardiac LA mass on echocardiography. Although transthoracic echocardiography (TTE) is the primary screening tool to detect any cardiac mass, transesophageal echocardiography (TEE) is proven superior to TTE in delineating the size, morphology, and exact site of origin of LA masses. We report a case, where the preoperative TTE diagnosed an LA mass which was later confirmed to be an extracardiac intrapericardial mass by cardiac magnetic resonance imaging and intraoperative TEE. The mass was compressing the LA, and the timely diagnosis avoided the opening of the LA for mass excision.

Transthoracic intracardiac catheters in perioperative management of pediatric cardiac surgery patients: a single-center experience

BACKGROUND

Transthoracic intracardiac catheters inserted under direct vision in the pulmonary artery and left atrium during cardiac surgery play major roles in the management of patients with complex congenital heart disease. We aimed to analyze the utility of transthoracic intracardiac catheters in the perioperative management of pediatric cardiac surgery patients and review catheter-related morbidity.

METHODS

The computerized register of all pediatric cardiac surgery patients in whom transthoracic intracardiac catheters were inserted from 2012 to 2019 in a tertiary referral center were reviewed.

RESULTS

Transthoracic pulmonary artery and left atrial catheters were inserted in 89 and 71 patients, respectively. The most common indications for pulmonary artery and left atrial catheters were total anomalous pulmonary venous connection (52%) and total cavopulmonary connection (58%) respectively. The most common reason for elevated pulmonary artery and left atrial pressure after cardiopulmonary bypass was left ventricular dysfunction. Transthoracic pulmonary artery catheters helped in diagnosing pulmonary hypertensive crisis (29%), surgical decision-making (14%), and ventilator therapy (16%). Left atrial catheters helped in the diagnosis of left ventricular dysfunction (54%). The incidence of morbidity was 8.9% for transthoracic pulmonary artery catheters and 9.8% for left atrial catheters.

CONCLUSION

Transthoracic pulmonary artery catheters help in the diagnosis and management of pulmonary hypertensive crisis, for making perioperative surgical decisions, and during ventilator therapy. Transthoracic left atrial catheters help in the diagnosis of left ventricular dysfunction in the perioperative period. The diagnostic and treatment benefits provided by transthoracic intracardiac catheters outweigh the minor adverse events, supporting their continued use in the perioperative period.

Comparison of Four Different Techniques for Estimation of Left Ventricular Volumes Using Intraoperative Real Time Three Dimensional Transesophageal Echocardiography--A Prospective Observational Study

OBJECTIVES

The primary objective of the present study was to compare cardiac output derived with four methods of QLab (Philips, Amsterdam, Netherlands) software using real-time three-dimensional (3D) transesophageal echocardiography, with cardiac output obtained with the 3D left ventricular outflow tract (LVOT) cardiac output method. The secondary objective was to assess left ventricular (LV) volumes, LV ejection fraction, and cardiac output derived with four different methods of real time 3D transesophageal echocardiography processed in QLab software and to determine whether these parameters differed among these four methods.

DESIGN

A prospective observational study.

SETTING

A tertiary referral center and a university level teaching hospital.

PARTICIPANTS

The study comprised 50 patients scheduled for elective coronary artery bypass surgery without any concomitant valvular lesions.

MEASUREMENTS AND MAIN RESULTS

Three-dimensional full-volume datasets were obtained in optimum conditions. The 3D datasets were analyzed using four different methods in QLab, version 9. In method A, LV volumes were derived without endocardial border adjustment. In method B, LV volumes were obtained after endocardial border adjustment in the long-axis view alone. In method C, the iSlice tool (Philips) was used to adjust the endocardial borders in 16 short-axis slices. In method D, endocardial borders were adjusted after dataset processing to obtain LV volumes. The cardiac output derived with the 3D echocardiography LVOT method was 3.93 ± 1.44 L/min, with method A was 3.26 ± 1.42 L/min, with method B was 3.51 ± 1.2 L/min, with method C was 4.01 ± 1.40 L/min, and with method D was 4.18 ± 1.58 L/min. There was a significant positive correlation between the cardiac output derived using the 3D LVOT method and method C (r = 0.71).

CONCLUSIONS

Readjusting the endocardial border contours resulted in higher LV volumes than the volumes estimated using semiautomated border algorithms. The iSlice method produced the highest and the most accurate LV volumes, although it required the longest time to analyze and derive results. The ejection fraction obtained with all four methods of QLab demonstrated no statistical differences and had a strong correlation with the two-dimensional echocardiography-derived left ventricular ejection fraction.

Guideline for the management of hip fractures 2020: Guideline by the Association of Anaesthetists

We convened a multidisciplinary Working Party on behalf of the Association of Anaesthetists to update the 2011 guidance on the peri-operative management of people with hip fracture. Importantly, these guidelines describe the core aims and principles of peri-operative management, recommending greater standardisation of anaesthetic practice as a component of multidisciplinary care. Although much of the 2011 guidance remains applicable to contemporary practice, new evidence and consensus inform the additional recommendations made in this document. Specific changes to the 2011 guidance relate to analgesia, medicolegal practice, risk assessment, bone cement implantation syndrome and regional review networks. Areas of controversy remain, and we discuss these in further detail, relating to the mode of anaesthesia, surgical delay, blood management and transfusion thresholds, echocardiography, anticoagulant and antiplatelet management and postoperative discharge destination. Finally, these guidelines provide links to supplemental online material that can be used at readers' institutions, key references and UK national guidance about the peri-operative care of people with hip and periprosthetic fractures during the COVID-19 pandemic.

Internal Jugular Vein Cannulation Using a 3-Dimensional Ultrasound Probe in Patients Undergoing Cardiac Surgery: Comparison Between Biplane View and Short-Axis View

OBJECTIVE

To compare the clinical performance in terms of procedure time, success rate, and cannulation attempts between ultrasound biplane view (BPX) and short-axis (SAX) view for internal jugular vein cannulation (IJV) in patients undergoing cardiac surgery.

DESIGN

Prospective, observational pilot study.

SETTING

University level tertiary referral hospital.

PATIENTS

The study comprised 100 patients between ages 18 and 75 years undergoing elective cardiac surgery.

INTERVENTIONS

One hundred patients were divided into 2 groups of 50 (BPX group and SAX group) by assigning the study participants alternatively to each group. IJV cannulation was performed using a 3-dimensional ultrasound probe in all patients with either BPX view (BPX group, n = 50) or the SAX view (SAX group, n = 50) by an experienced anesthesiologist.

MEASUREMENTS AND MAIN RESULTS

Time required for imaging, time for IJV puncture, time for guidewire confirmation, number of needle punctures and needle redirections, and incidence of posterior wall puncture were noted in both groups. In addition, the quality of needle visualization and the incidence of complications were recorded. The time taken for imaging was significantly greater in the BPX group than in the SAX group (9.52 ± 2.69 s v 7.94 ± 2.55 s; p = 0.0034), whereas the time taken for IJV puncture (10.39 ± 2.33 s v 23.7 ± 2.46 s; p < 0.0001), time taken for confirmation of guidewire (32.94 ± 4.50 s v 57.64 ± 7.14 s; p < 0.0001), and the incidence of posterior wall puncture (4% v 26%; p = 0.0022) were significantly less in the BPX group than in the SAX group. The total number of attempts taken to puncture the IJV was fewer in the BPX group than in the SAX group (55 v 78). Successful puncture of the IJV occurred on the first attempt in 90% of patients in the BPX group, whereas it was only 50% in the SAX group (p < 0.0001). The quality of needle visualization was good in 90% of patients in the BPX group, whereas it was only 6% in the SAX group. The number of needle redirections for IJV puncture was less in the BPX group than in the SAX group (48 v 116). The incidence of complications was not significant between the 2 groups.

CONCLUSION

The results suggested that the BPX view may be a safer, feasible and more reliable method than the SAX view for IJV cannulation in cardiac surgical patients.

International Nosocomial Infection Control Consortium (INICC) report, data summary of 45 countries for 2012-2017: Device-associated module

BACKGROUND

We report the results of International Nosocomial Infection Control Consortium (INICC) surveillance study from January 2012 to December 2017 in 523 intensive care units (ICUs) in 45 countries from Latin America, Europe, Eastern Mediterranean, Southeast Asia, and Western Pacific.

METHODS

During the 6-year study period, prospective data from 532,483 ICU patients hospitalized in 242 hospitals, for an aggregate of 2,197,304 patient days, were collected through the INICC Surveillance Online System (ISOS). The Centers for Disease Control and Prevention-National Healthcare Safety Network (CDC-NHSN) definitions for device-associated health care-associated infection (DA-HAI) were applied.

RESULTS

Although device use in INICC ICUs was similar to that reported from CDC-NHSN ICUs, DA-HAI rates were higher in the INICC ICUs: in the medical-surgical ICUs, the pooled central line-associated bloodstream infection rate was higher (5.05 vs 0.8 per 1,000 central line-days); the ventilator-associated pneumonia rate was also higher (14.1 vs 0.9 per 1,000 ventilator-days,), as well as the rate of catheter-associated urinary tract infection (5.1 vs 1.7 per 1,000 catheter-days). From blood cultures samples, frequencies of resistance, such as of Pseudomonas aeruginosa to piperacillin-tazobactam (33.0% vs 18.3%), were also higher.

CONCLUSIONS

Despite a significant trend toward the reduction in INICC ICUs, DA-HAI rates are still much higher compared with CDC-NHSN's ICUs representing the developed world. It is INICC's main goal to provide basic and cost-effective resources, through the INICC Surveillance Online System to tackle the burden of DA-HAIs effectively.