Retrosternal Percutaneous Tracheostomy: An Approach for Predictably Impossible Classic Tracheostomy

Percutaneous tracheostomy is a routine procedure in intensive care units. In cases of very low position of the larynx, cervical spine deformation, morbid obesity, or neck tumor, performance of the classic tracheostomy is inapplicable. Retrosternal approach to tracheostomy in such 20 patients is herein reported. After preoperative neck computerized tomography to define the neck anatomy, a small suprasternal incision followed by a short retrosternal tissue dissection to expose the trachea was done; the trachea was then catheterized at the level of the 2nd ring in the usual tracheostomy manner. The immediate and late (≥6 months) outcomes were similar to that of the standard tracheostomy. Thus, percutaneous retrosternal tracheostomy is safe in patients with abnormal positioning of the trachea or neck constitution. It is a bedside applicable technique, that, however, requires caution to avoid hazardous vascular complications

Cerebral monitoring with transcranial Doppler ultrasonography improves neurologic outcome during repairs of acute type A aortic dissection

ObjectiveNeurologic complications after repair of acute type A aortic dissection remain significant. The use of power M-mode transcranial Doppler monitoring to verify cerebral blood flow during these repairs might decrease cerebral ischemia by correcting malperfusion. The purpose of this study was to analyze the use of power M-mode transcranial Doppler monitoring during repairs of acute type A dissection with regard to neurologic outcome.MethodsWe performed a prospective study of patients undergoing repairs of acute type A aortic dissection. Repairs included profound hypothermic circulatory arrest and retrograde cerebral perfusion. Patients in whom transcranial Doppler monitoring was used to monitor cerebral blood flow and modify operative technique during repair (study group) were compared with those without monitoring and modification (control group).ResultsBetween September 2001 and October 2003, we repaired 56 cases of acute type A dissection. Power M-mode transcranial Doppler monitoring was used in 50% (28/56) of cases. Power M-mode transcranial Doppler monitoring altered operative cannulation and guided retrograde cerebral perfusion flow in 28.5% (8/28) and 78.6% (22/28) of cases, respectively. Two patients presented with preoperative stroke, one in each group. One operative death occurred in each group. In-hospital mortality and the occurrence of new stroke were not significantly different between the 2 groups. Temporary neurologic dysfunction occurred less often in the study group (14.8% [4/27] vs 51.8% [14/27], P = .008).ConclusionsIdentification of cerebral malperfusion requires cerebral monitoring. By ensuring cerebral blood flow by using power M-mode transcranial Doppler monitoring and correcting cerebral malperfusion by modifying operative technique, neurologic outcome was improved during repairs of acute type A aortic dissection

Glomerular filtration rate is superior to serum creatinine for prediction of mortality after thoracoabdominal aortic surgery

BackgroundClinically evident renal disease (dialysis, history of renal insufficiency, or serum creatinine >2.0 mg/dL) is a known risk factor for mortality after thoracoabdominal aortic aneurysm repair. We extended this concept to the questions of whether subclinical renal disease is also a risk factor and how best to identify subclinical disease. We hypothesized that the glomerular filtration rate (GFR) would be a more sensitive determinant of renal function than serum creatinine alone.MethodsBetween 1991 and 2004, we repaired 1106 thoracoabdominal aortic aneurysms and descending thoracic aortic aneurysms. The median age was 67 years. There were 400 (36%) women and 706 (64%) men. We estimated GFR by using the Cockcroft-Gault equation. We divided baseline serum creatinine and baseline GFR into quartiles and estimated the association of the quartiles with 30-day postoperative mortality by χ2 testing. We further subdivided the population into patients with and without clinically evident renal disease and repeated the analysis in the patients without clinically apparent disease (n = 869).ResultsClinically apparent renal disease was highly associated with 30-day mortality (odds ratio, 3.2; P < .0001). In all patients, serum creatinine quartile and GFR quartile were also both highly significantly associated with 30-day mortality (P < .0001). In patients without clinically apparent renal disease, both creatinine and GFR predicted additional mortality, but GFR was a much stronger predictor (P < .02 for creatinine vs <.0001 for GFR). In these patients, mortality ranged from 5% in the best GFR quartile to 27% in the worst. Taken as continuous variables in logistic regression equations, serum creatinine had no discrimination in patients without clinical disease (P = .73), whereas GFR remained strong (P <.0001).ConclusionsPreoperative renal function is an important determinant of early mortality even in patients without clinically evident disease. Estimated GFR is a much more powerful determinant of mortality risk than serum creatinine alone

Tumor Treating Fields (TTFields) demonstrate antiviral functions in vitro, and safety for application to COVID-19 patients in a pilot clinical study

Coronaviruses are the causative agents of several recent outbreaks, including the COVID-19 pandemic. One therapeutic approach is blocking viral binding to the host receptor. As binding largely depends on electrostatic interactions, we hypothesized possible inhibition of viral infection through application of electric fields, and tested the effectiveness of Tumor Treating Fields (TTFields), a clinically approved cancer treatment based on delivery of electric fields. In preclinical models, TTFields were found to inhibit coronavirus infection and replication, leading to lower viral secretion and higher cell survival, and to formation of progeny virions with lower infectivity, overall demonstrating antiviral activity. In a pilot clinical study (NCT04953234), TTFields therapy was safe for patients with severe COVID-19, also demonstrating preliminary effectiveness data, that correlated with higher device usage

Identification of clastic dikes as holocene seismites in the Dead Sea basin

International audienceOff-fault seismogenic deformation in sediments (seismites) has proved useful for recovering long continuous records of earthquake activity. An important example of seismite is clastic dikes that were formed 'dynamically' by fracturing of the host rock and injection of clastic materials. However, they are easily confused with 'passive' dikes that were filled by deposition into preexisting fissures. This study demonstrates the application of anisotropy of the magnetic susceptibility (AMS) analyses to recognition of seismites. We assume that different sources of dike fill have different microfabrics, which manifest in different magnetic fabrics. To test this hypothesis we studied over 250 Holocene clastic dikes, exposed by deep incision into the lacustrine 70-15 ka Lisan Formation in the Dead Sea basin. Typically, they are vertical, up to 30-40 m high, and up to 0.4 m thick. In map view they appear in a radial arrangement spanning a sector of 60 degrees with projected strikes that converge at a structural dome above a rising salt diapir. Field relations and AMS analyses show that 'passive' dikes filled from above have vertical Kmin directions, compatible with sedimentary features. Conversely, horizontal to sub-horizontal Kmin directions occur in dikes that show segmentation typical of horizontal propagation of the fractures and lateral material transport. Vertical zoning of the clay and silt is interpreted as evidence of multiple injection events. Optical Stimulation Luminescence (OSL) ages, spanning 7-14 ka, are in agreement with dike truncation by undisturbed late Holocene alluvium. We conclude that the upward indentation of a salt diapir induced a local stress perturbation, which triggered the formation of a radial set of fractures. Subsequently the fractures were filled by horizontal injection of fine elastics pressurized by earthquake vibrations. Sedimentation from above occurred where the tops of the dikes reached the surface and remained open

Identification of clastic dikes as holocene seismites in the Dead Sea basin

International audienceOff-fault seismogenic deformation in sediments (seismites) has proved useful for recovering long continuous records of earthquake activity. An important example of seismite is clastic dikes that were formed 'dynamically' by fracturing of the host rock and injection of clastic materials. However, they are easily confused with 'passive' dikes that were filled by deposition into preexisting fissures. This study demonstrates the application of anisotropy of the magnetic susceptibility (AMS) analyses to recognition of seismites. We assume that different sources of dike fill have different microfabrics, which manifest in different magnetic fabrics. To test this hypothesis we studied over 250 Holocene clastic dikes, exposed by deep incision into the lacustrine 70-15 ka Lisan Formation in the Dead Sea basin. Typically, they are vertical, up to 30-40 m high, and up to 0.4 m thick. In map view they appear in a radial arrangement spanning a sector of 60 degrees with projected strikes that converge at a structural dome above a rising salt diapir. Field relations and AMS analyses show that 'passive' dikes filled from above have vertical Kmin directions, compatible with sedimentary features. Conversely, horizontal to sub-horizontal Kmin directions occur in dikes that show segmentation typical of horizontal propagation of the fractures and lateral material transport. Vertical zoning of the clay and silt is interpreted as evidence of multiple injection events. Optical Stimulation Luminescence (OSL) ages, spanning 7-14 ka, are in agreement with dike truncation by undisturbed late Holocene alluvium. We conclude that the upward indentation of a salt diapir induced a local stress perturbation, which triggered the formation of a radial set of fractures. Subsequently the fractures were filled by horizontal injection of fine elastics pressurized by earthquake vibrations. Sedimentation from above occurred where the tops of the dikes reached the surface and remained open

Novel Phage Display-Derived Anti-Abrin Antibodies Confer Post-Exposure Protection against Abrin Intoxication

Abrin toxin is a type 2 ribosome inactivating glycoprotein isolated from the seeds of Abrus precatorius (jequirity pea). Owing to its high toxicity, relative ease of purification and accessibility, it is considered a biological threat agent. To date, there is no effective post-exposure treatment for abrin poisoning and passive immunization remains the most effective therapy. However, the effectiveness of anti-abrin monoclonal antibodies for post-exposure therapy following abrin intoxication has not been demonstrated. The aim of this study was to isolate high affinity anti-abrin antibodies that possess potent toxin-neutralization capabilities. An immune scFv phage-display library was constructed from an abrin-immunized rabbit and a panel of antibodies (six directed against the A subunit of abrin and four against the B subunit) was isolated and expressed as scFv-Fc antibodies. By pair-wise analysis, we found that these antibodies target five distinct epitopes on the surface of abrin and that antibodies against all these sites can bind the toxin simultaneously. Several of these antibodies (namely, RB9, RB10, RB28 and RB30) conferred high protection against pulmonary intoxication of mice, when administered six hours post exposure to a lethal dose of abrin. The data presented in this study demonstrate for the first time the efficacy of monoclonal antibodies in treatment of mice after pulmonary intoxication with abrin and promote the use of these antibodies, one or several, for post-exposure treatment of abrin intoxication