Discover and publish cutting edge, open research.

Browse 8,865 multi-disciplinary research preprints

Most recent

XH Cao

and 3 more

Aim Tracheal tubes were placed together with bronchial blocker into trachea, which would result in increased airway resistance and hypoventilation in young children. The aim of this study is to investigate the efficacy and safety of laryngeal mask way (LMA) with the bronchial blocker for OLV in children undergoing thoracoscopic surgery. Methods: Sixty children undergoing thoracoscopic surgery were randomly divided into two groups in this prospective, controlled clinical study. The group A received OLV using the bronchial blocker via LMA, while the group B received OLV using the extraluminal technique of the bronchial blocker. The placement time of LMA and the bronchial blocker was noted. Respiratory mechanic parameters [tidal volume (Vt), compliance of lung (CL) and PETCO2] were recorded. Postoperative complications were also recorded. Results: The placement time was shorter in group A than in the group B (3.9 ± 0.5 vs. 5.2± 0.7 min, P <0.01). Vt and CL 30 min after the initiation of OLV were increased in group A than in group B (97.3±7.4 vs 89.9±7.8 ml, 23.2±2.6 vs 20.3±3.5 ml/cmH2O, P < 0.01, respectively), while PETCO2 in group A were lower compared to the group B (39.4±4.3 vs. 43.5±4.8 mmHg, P = 0.01). At 30 min after the initiation of OLV, PaO2 was higher in group A (236.6±41.0 vs 208.2±45.9 mmHg, P =0.014), while PaCO2 were lower in group A (43.8± 2.5 vs 46.3± 4.1 mmHg, P = 0.006), there were statistical significant differences in PaO2 and PaCO2 between the 2 groups. Conclusions: Use of the bronchial blocker via LMA for OLV takes less placement time and improves ventilation and with fewer complications compared to the extraluminal technique. It provides a novel approach to lung isolation in pediatric thoracic anesthesia.

Browse more recent preprints

Recently published in scholarly journals

Gary Ghahremani

and 2 more

Summary Background: Torus is a protuberant and lobulated exostosis that develops on the lingual aspect of the jaws or hard palate in 10-30% of adults. They can interfere with mastication, speech, oral hygiene, and denture placement. Their enlargement with advancing age may also lead to superficial ulceration, inflammation, osteonecrosis and various other complications. Methods: A retrospective analysis of the authors’ experience with 17 adults who had large symptomatic tori was performed. The patients were examined by intraoral imaging and radiographic or computed tomography of their maxillofacial bones. Their dental and medical records were reviewed along with the pertinent literature concerning the prevalence and reported complications of this entity. Results: This series included 6 men and 11 women, ranging in age from 36 to 85 years (Mean age: 56.5 years).There were 6 patients with torus mandibularis, 8 with torus palatinus, and 3 with torus maxillaris. Four of our 17 patients required surgical excision of their tori because of large size, recurrent superficial erosions and associated symptoms. Conclusion: The majority of tori are asymptomatic and incidental finding, but the more prominent tori are prone to mucosal inflammation and ulceration that may require surgical removal of the lesion. Large tori can also interfere with mastication, speech, dental hygiene, placement and function of prosthetic dentures, and may cause snoring, sleep apnea or other complications. Therefore, the practicing physicians should be familiar with the appearance, radiological features, clinical implications and management of tori.

Wahaj Munir

and 3 more

Background: Acute type A aortic dissection (ATAAD), is a surgical emergency often requiring intervention on the aortic root. There is much controversy regarding root management; aggressively pursuing a root replacement, versus more conservative approaches to preserve native structures. Methods: Electronic database search we performed through PubMed, Embase, SCOPUS, google scholar and Cochrane identifying studies that reported on outcomes of surgical repair of ATAAD through either root preservation or replacement. The identified articles focused on short- and long-term mortalities, and rates of re-operation on the aortic root. Results: There remains controversy on replacing or preserving aortic root in ATAAD. Current evidence supports practice of both trends following an extensive decision-making framework, with conflicting series suggesting favourable results with both procedures as the approach that best defines higher survival rates and lower perioperative complications. Yet, the decision to perform either approach remains surgeon decision and bound to the extent of the dissection and tear entries in strong correlation with status of the aortic valve and involvement of coronaries in the dissection. Conclusions: There exists much controversy regarding fate of the aortic root in ATAAD. There are conflicting studies for impact of root replacement on mortality, whilst some study’s report no significant results at all. There is strong evidence regarding risk of re-operation being greater when root is not replaced. Majority of these studies are limited by the single centred, retrospective nature of these small sample sized cohorts, further hindered by potential of treatment bias.

Matthew Sussman

and 9 more

The recognition of fibrinolysis phenotypes in trauma patients has led to a reevaluation of antifibrinolytic therapy (AF). Many cardiac patients also receive AF, however the distribution of fibrinolytic phenotypes in that population is unknown. The purpose of this study was to fill that gap. Methods: Data were retrospectively reviewed from 78 cardiac surgery patients. Phenotypes were defined as hypofibrinolytic (LY30 <0.8%), physiologic (LY30 0.8-3.0%) and hyperfibrinolytic (LY30 >3%). Continuous variables were expressed as M ± SD or median (interquartile range). Results: The study population was 65±10 yrs old, 74% male, average body mass index of 29±5 kg/m2. Fibrinolytic phenotypes were distributed as physiologic=45%, hypo=32% and hyper = 23%. There was no obvious effect of age, gender, race, or ethnicity on the distribution of fibrinolysis phenotypes; 47% received AF. The time with chest tube during post-operative recovery was longer in those who received AF (4[3,5] days) vs no AF (3[2,4] days), P=0.037). All cause morbidity occurred in 51% of patients who received AF vs 25% with no AF (p=0.017). However, with AF vs no AF, apparent differences in median chest tube output (1379 vs 820ml, p=0.075), hospital LOS (13 vs 10 days, P=0.873), estimated blood loss (1100 vs 775 ml, P=0.127), units of transfused RBCs (4 vs 2], P=0.152) or all-cause mortality (5.4% [2/37] vs 10% [4/41], P=0.518) were not statistically significant. Conclusion: This is the first description of three distinctly different fibrinolytic phenotypes in cardiac surgery patients. In this population, the use of AF was associated with increased morbidity.

Arushi Singh

and 6 more

Background: Ibrutinib is associated with atrial fibrillation (AF), though echocardiographic predictors of AF have not been studied in this population. We sought to determine whether left atrial (LA) strain on transthoracic echocardiography could identify patients at risk for developing ibrutinib-related atrial fibrillation (IRAF). Methods: We performed a retrospective review of 66 patients who had an echocardiogram prior to ibrutinib treatment. LA strain was measured with TOMTEC Imaging Systems, obtaining peak atrial longitudinal strain (PALS) and peak atrial contraction strain (PACS) on 4-chamber and 2-chamber views. Statistical analysis was performed with Chi-square analysis, T-test, or binomial regression analysis, with a p-value < 0.05 considered statistically significant. Results: Twenty-two patients developed IRAF (33%). Age at initiation of ibrutinib was significantly associated with IRAF (65.1 years vs. 74.1 years, p = 0.002). Mean ibrutinib dose was lower among patients who developed IRAF (388.2 ± 121.7 vs. 448.6 ± 88.4, p = 0.025). E/e’ was significantly higher among patients who developed IRAF (11.5 vs. 9.3, p = 0.04). PALS was significantly lower in patients who developed AF (30.3% vs. 36.3%, p = 0.01). On multivariate regression analysis, age, PALS and PACS were significantly associated with IRAF. On multivariate regression analysis, only PACS remained significantly associated with IRAF while accounting for age. Conclusions: Age, ibrutinib dose, E/e’, and PALS on pre-treatment echocardiogram were significantly associated with development of IRAF. On multivariate regression analyses, age, PALS and PACS remained significantly associated with IRAF. Impaired LA mechanics add to the assessment of patients at risk for IRAF

James Hummel

and 1 more

We thank Medina et al. for their interest in our recent work on QTc prolongation associated with treatment of COVID-19 patients with hydroxychloroquine and azithromycin. As they appropriately point out in their letter, genetic variation is likely a significant determinant of QT prolongation in the population at large and in COVID-19 patients specifically. While drugs causing acquired long QT syndrome and torsades de pointes are generally blockers of IKr, repolarization results from the aggregate of multiple inward and outward currents. Patients with sub-clinical defects in any of these ion channels can have normal or only slightly prolonged baseline QT intervals, but may possess decreased repolarization reserve leading to an exaggerated response to IKr blockade (1).  In our study, a baseline QTc of > 460 ms was associated with excessive QTc prolongation, and this likely represents a group of patients with sub-clinical cardiac ion channel mutations (so called “first hit”) (2). We also agree that many patients with latent mutations demonstrate a normal baseline QT, which gets prolonged with the addition of a drug or a change in the clinical condition “second hit” (3). The patients in our study who exhibited QTc prolongation were generally acutely ill, and displayed “multiple hits” that led to QTc prolongation and it is certainly plausible that many may have had sub-clinical cardiac ion mutations. We therefore wholeheartedly agree that pharmacogenetics should be considered in studies of drug-induced QT prolongation, however this information is rarely available to include for acutely ill patients. And while it makes sense to obtain genetic profiles prior to administration of QT-prolonging medications, that can only be performed in the elective outpatient setting, while taking into consideration medical, ethical and social issues related to asymptomatic genetic screening (e.g. cost, reimbursement, informed consent, etc…). There is significant interest in building genomic databases, and when this becomes a reality for the population at large we believe that genetic information should certainly be included in studies of QT prolongation.Roden DM Long QT syndrome: reduced repolarization reserve and the genetic link. J Intern Med. 2006 Jan; 259(1):59-69.Napolitano C, Schwartz PJ, Brown AM, et al. Evidence for a cardiac ion channel mutation underlying drug-induced QT prolongation and life-threatening arrhythmias. J Cardiovasc Electrophysiol. 2000;11:691–6Sauer AJ and Newton-Cheh C. Clinical and genetic determinants of torsade de pointes risk. Circulation. 2012;125:1684-94.

Browse more published preprints

How it works

Upload or create your research work
You can upload Word, PDF, LaTeX as well as data, code, Jupyter Notebooks, videos, and figures. Or start a document from scratch.
Disseminate your research rapidly
Post your work as a preprint. A Digital Object Identifier (DOI) makes your research citeable and discoverable immediately.
Get published in a refereed journal
Track the status of your paper as it goes through peer review. When published, it automatically links to the publisher version.
Learn More
Featured collections
Explore More Collections

Other benefits of Authorea

Multidisciplinary

A repository for any field of research, from Anthropology to Zoology

Comments

Discuss your preprints with your collaborators and the scientific community

Interactive Figures

Not just PDFs. You can publish d3.js and Plot.ly graphs, data, code, Jupyter notebooks

Featured templates
Featured and interactive
Journals with direct submission
Explore All Templates