Atrial synchronous left ventricular only pacing with VDD pacemaker system – A cost effective alternative to conventional cardiac resynchronization therapy

Introduction

Atrial synchronous left ventricular (LV) only pacing using two leads and VDD pacemaker could be a cost effective alternative to conventional cardiac resynchronization therapy (CRT).

Methods

We implanted right atrial (RA) and LV leads with VDD pulse generator (LV only pacing) in five carefully screened heart failure patients who could not afford conventional CRT. All had NYHA class III/IV symptoms despite maximal guideline directed medical therapy. The sensed atrioventricular delay was programmed to pre-excite the LV and achieve fusion beat. Response to treatment was assessed at 6 months.

Results

Four patients were males. The mean age was 58 ± 12 years. At follow up, there was improvement in electrocardiographic, and echocardiographic parameters: Mean QRS duration decreased from 174 ± 17 msec to 128 ± 10.9 msec (p = 0.009), LV end-diastolic diameter decreased from 73.2 ± 12 mm to 65.8 ± 9.6 mm (p = 0.026), LV end-systolic diameter decreased from 65 ± 12 mm to 54 ± 10 mm (p = 0.020). There was a trend towards reduction of LV end-systolic and end-diastolic volumes. LV ejection fraction improved from 25 ± 6% to 34 ± 6% (p = 0.013) and left atrial dimension reduced from 44 ± 4 mm to 39 ± 5 mm (p = 0.045). All patients improved clinically.

Conclusion

RA-LV pacing using VDD pacemaker is a safe and effective technique of CRT. This may be a cost effective alternative to conventional CRT for patients in developing countries.     

Bedside upper gastrointestinal series in critically ill low birth weight infants

Background

The upper gastrointestinal (UGI) series is the preferred method for the diagnosis of malrotation. A bedside UGI technique was developed at our institution for use in low birth weight, critically ill neonates to minimize the risks of transportation from the neonatal intensive care unit (NICU) such as hypothermia and dislodgement of support lines and tubes.

Objective

To determine the ability of a bedside UGI technique to identify the position of the duodenojejunal junction (DJJ) in low birth weight, critically ill infants in the NICU.

Materials and methods

We retrospectively reviewed bedside UGI examinations performed in premature infants weighing less than 1,500 g from 2008 to 2013 and correlated the findings with clinical data, imaging studies and surgical findings.

Results

Of 27 patients identified (weight range: 633–1,495 g), 21 (78%) bedside UGI series were diagnostic. Twenty of 27 cases (74%) demonstrated normal intestinal rotation. One case demonstrated malrotation with midgut volvulus, which was confirmed at surgery. In six cases (22%), the position of the DJJ could not be accurately determined. No cases of malrotation with midgut volvulus were missed. None of the patients with normal bedside UGI studies was found to have malrotation based on clinical follow-up (mean: 20 months), surgical findings or further imaging.

Conclusion

The bedside UGI is a useful technique to exclude malrotation in critically ill neonates and minimizes potential risks of transportation to the radiology suite. Pitfalls that may preclude a diagnostic examination include incorrect timing of radiographs, patient rotation, suboptimal enteric tube position and bowel distention. In cases of diagnostic uncertainty, a follow-up study should be performed.     

Coincidental diagnosis of tuberculous lymphadenitis: a case report

The aim of this case report was to present a case of multiple calcified tuberculous lymph nodes found on a panoramic radiograph coincidently diagnosed in an endodontic clinic. A detailed discussion on the differential diagnosis of similar such calcification found in the same region is also presented. A 14‐year‐old girl was referred to our department with the complaint of painless swelling in the left side of the lower jaw. Clinical and radiographical examinations were performed, leading to the initial diagnosis of chronic periapical abscess. The patient's medical history was re‐evaluated. Advanced imaging and excisional biopsy were performed in order to confirm the final diagnosis. Regarding the presenting signs and symptoms of bilateral carious mandibular molars, a periapical inflammatory process was considered in the provisional diagnosis. A thorough examination and investigations were suggestive of cervical tuberculous lymphadenitis (scrofula), and the patient underwent excision of the same. The clinician should consider the possibility of chronic granulomatous inflammatory lesions in the differential diagnosis of radiopaque lesions.     

Merits of multicolor imaging for tractional retinal detachment

Purpose:To compare multicolor imaging (MCI) with Optos color fundus photography (OCFP) for the evaluation of morphology and extent of preretinal membranes in diabetic tractional retinal detachments (TRD).Methods:In this retrospective study, 30 eyes with diabetic TRDs were imaged using the MCI feature of the Heidelberg Spectralis Spectral-domain optical coherence tomography (SD-OCT) and color photo using the Optos Daytona ultra-widefield fundus camera. Two investigators independently graded and determined the agreeability between the two modalities with respect to the extent of the TRD and preretinal membranes on the SD-OCT B-scan images.Results:The MCI provided better visualization of the attachments and traction points of the posterior hyaloid face and preretinal membranes and is comparable to the SD-OCT B-scan images. The inter-rater agreeability rates for OCFP had a Kappa (κ) value of 0.37, while the MCI had a κ value of 0.46. When comparing between images of different wavelengths, grading using infrared reflectance (IR) had a poor agreement (−0.04 ± 0.04) while green reflectance (GR) (0.46 ± 0.32) and blue reflectance (BR) (0.53 ± 0.19) had a moderate agreement. The composite MCI and GR images also had comparatively higher intraclass coefficient when compared to the OCFP (0.25 [−0.09–0.55]) and IR (−0.03 [−0.39–0.34]) images.Conclusion:MCI is more sensitive for determining the extent of TRDs and for the detection of secondary membranes when compared to OCFP, thus, aiding in better surgical planning.     

The effect of various in-vitro and ex-vivo parameters on irrigant flow and apical pressure using manual syringe needle irrigation: Systematic review

BackgroundFluid dynamics is a majorly neglected aspect to be studied in root canal irrigation. The fundamental rule to understand mechanics is to observe patterns of flow during the process. Thus, this work is conducted to do a systemic assessment of the in-vitro and ex-vivo based studies to evaluate the effect of various parameters on the irrigant flow and apical pressure on using a manual syringe needle for root canal irrigation.MethodsThe literature search was conducted through libraries such as PubMed (Medline), CINAHL, Embase, Scopus and other hand literature from Google Scholar, the British medical library etc. The systematic review was reported following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. As they include studies that were in-vitro and ex-vivo based, the risk of bias of the selected articles was assessed using a customized tool based on the previous literature and parameters evaluated in the studies included.ResultsThe literature search resulted in 101 items of which 19 records were included in this review. Results reported that multiple factors and parameters were assessed to evaluate the flow and apical pressures on using manual syringe needle irrigation.ConclusionsPresent systematic review gives insights in-depth about the irrigation dynamics of manual syringe needle irrigation. Besides, it is inconclusive to compile a single factor or a single parameter contributing to the enhanced irrigant flow and least apical pressures.     

术中胆道造影在腹腔镜胆囊切除术中发现胆道损伤的作用

目的：评估术中胆道造影（IOC）在早期发现腹腔镜胆囊切除术（LC）术中胆道损伤的作用。方法：回顾分析31例LC术后胆道损伤的部位，机理，诊断时间，治疗方法及结果，并对是否行IOC进行评估。结果：胆道错认引起胆道损伤共19例，其中12例IOC显示胆道错认，致胆道部分切开损伤，腹腔镜下行I期修复或开腹修复，T管引流，但无并发症。19例中3例IOC误读及4例未行IOC患者中发生迷走胆管损伤2例，胆总管完全离断1例，胆总管完全离断合并胆道缺损2例，本组有2例损伤发生于IOC后，结论：行IOC并正确阅读可及时发现腹腔镜胆囊切除术中胆道错认所致的胆道损伤，从而防止随之可能发生的严重并发症。     

Nitrite Anion Therapy Protects Against Chronic Ischemic Tissue Injury in db/db Diabetic Mice in a NO/VEGF-Dependent Manner

Nitrite anion has been demonstrated to be a prodrug of nitric oxide (NO) with positive effects on tissue ischemia/reperfusion injury, cytoprotection, and vasodilation. However, effects of nitrite anion therapy for ischemic tissue vascular remodeling during diabetes remain unknown. We examined whether sodium nitrite therapy altered ischemic revascularization in BKS-Lepr^db/db mice subjected to permanent unilateral femoral artery ligation. Sodium nitrite therapy completely restored ischemic hind limb blood flow compared with nitrate or PBS therapy. Importantly, delayed nitrite therapy 5 days after ischemia restored ischemic limb blood flow in aged diabetic mice. Restoration of blood flow was associated with increases in ischemic tissue angiogenesis activity and cell proliferation. Moreover, nitrite but not nitrate therapy significantly prevented ischemia-mediated tissue necrosis in aged mice. Nitrite therapy significantly increased ischemic tissue vascular endothelial growth factor (VEGF) protein expression that was essential for nitrite-mediated reperfusion of ischemic hind limbs. Nitrite significantly increased ischemic tissue NO bioavailability along with concomitant reduction of superoxide formation. Lastly, nitrite treatment also significantly stimulated hypoxic endothelial cell proliferation and migration in the presence of high glucose in an NO/VEGF-dependent manner. These results demonstrate that nitrite therapy effectively stimulates ischemic tissue vascular remodeling in the setting of metabolic dysfunction that may be clinically useful.     

Adaptability on Shifting Ground: a Rapid Qualitative Assessment of Multi-institutional Inpatient Surge Planning and Workforce Deployment During the COVID-19 Pandemic

BackgroundDuring the initial wave of COVID-19 hospitalizations, care delivery and workforce adaptations were rapidly implemented. In response to subsequent surges of patients, institutions have deployed, modified, and/or discontinued their workforce plans.ObjectiveUsing rapid qualitative methods, we sought to explore hospitalists’ experiences with workforce deployment, types of clinicians deployed, and challenges encountered with subsequent iterations of surge planning during the COVID-19 pandemic across a collaborative of hospital medicine groups.ApproachUsing rapid qualitative methods, focus groups were conducted in partnership with the Hospital Medicine Reengineering Network (HOMERuN). We interviewed physicians, advanced practice providers (APP), and physician researchers about (1) ongoing adaptations to the workforce as a result of the COVID-19 pandemic, (2) current struggles with workforce planning, and (3) evolution of workforce planning.Key ResultsWe conducted five focus groups with 33 individuals from 24 institutions, representing 52% of HOMERuN sites. A variety of adaptations was described by participants, some common across institutions and others specific to the institution’s location and context. Adaptations implemented shifted from the first waves of COVID patients to subsequent waves. Three global themes also emerged: (1) adaptability and comfort with dynamic change, (2) the importance of the unique hospitalist skillset for effective surge planning and redeployment, and (3) the lack of universal solutions.ConclusionsHospital workforce adaptations to the COVID pandemic continued to evolve. While few approaches were universally effective in managing surges of patients, and successful adaptations were highly context dependent, the ability to navigate a complex system, adaptability, and comfort in a chaotic, dynamic environment were themes considered most critical to successful surge management. However, resource constraints and sustained high workload levels raised issues of burnout.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11606-022-07480-x.KEY WORDS: COVID-19, hospital medicine, workforce planning, surge planning, focus groups, qualitative     

Possible roles of excess tryptophan metabolites in cancer

Tryptophan is metabolized through serotonin, indole, and kynurenine (KN) pathways. Uptake of an excess amount of tryptophan accompanied with vitamin B6 deficiency may result in the accumulation of higher concentrations of metabolites mainly from the KN pathways in the bladder. These metabolites could interact with nitrite to become mutagenic nitrosamines. They could be a promoter in the initiator–promoter model of carcinogenesis. They produced bladder cancer when implanted in the bladder. They also interact with transition metals copper or iron to form reactive radicals or reactive oxygen species (ROS). Some metabolites, 3‐hydroxy‐anthranilic acid, were autooxidized to mutagenic cinnabarinic and anthranilyl radical intermediates. These radical intermediates could also be ligands that interact with aryl hydrocarbon receptor (AhR) and induce xenobiotic metabolizing enzymes (XMEs) to metabolize contaminated carcinogens. When tryptophan is exposed to either visible or UV light, a photoproduct of 6‐formylindolo[3,2b]‐carbazole is formed, which has a very high affinity for the AhR that plays a role in carcinogenesis. This review gives an insight into various mechanisms through which tryptophan metabolites cause carcinogenesis. It could be concluded that tryptophan metabolites play a complementary role in promoting carcinogenesis along with carcinogens like aflatoxin, CCl₄, 2‐acetylaminofluorene, 4‐aminobiphenyl, 2‐naphthylamine, or N‐[4‐(5‐nitro‐2‐furyl)?2‐thiazolyl] formamide. The underlying mechanisms could be their autoxidation, exposure to either visible or UV light, interaction with nitrite or transition metals to form reactive intermediates, serving as ligands to interact with an AhR that is known to play a role in carcinogenesis through induction of XMEs. Further research is warranted.Environ. Mol. Mutagen. 52:81–104, 2011. © 2010 Wiley‐Liss, Inc.     

Verapamil as an adjunct to local anaesthetic for brachial plexus blocks

Background: Calcium channel blockers potentiate the effects of local anaesthetics. We examined the effect of adding verapamil to local anaesthetic solution on anaesthetic duration in patients undergoing surgery under brachial plexus block.