SciCombinator

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Concept: Thorax

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OBJECTIVE: Anterior chest thrusts (with the subject sitting or standing and thrusts applied to the lower sternum) are recommended by the Australian Resuscitation Council as part of the sequence for clearing upper airway obstruction by a foreign body. Lateral chest thrusts (with the victim lying on their side) are no longer recommended due to a lack of evidence. We compared anterior, lateral chest and abdominal thrusts in the generation of airway pressures using a suitable animal model. METHODS: This was a repeated-measures, cross-over, clinical trial of eight anaesthetised, intubated, adult pigs. For each animal, ten trials of each technique were undertaken with the upper airway obstructed. A chest/abdominal pressure transducer, a pneumotachograph and an intra-oesophageal balloon catheter recorded chest/abdominal thrust, expiratory air flows, airway and intrapleural pressures, respectively. RESULTS: The mean (SD) thrust pressures generated for the anterior, lateral and abdominal techniques were 120.9 (11.0), 135.2 (20.0), and 142.4 (27.3) cmH(2)O, respectively (p<0.0001). The mean (SD) peak expiratory airway pressures were 6.5 (3.0), 18.0 (5.5) and 13.8 (6.7) cmH(2)O, respectively (p<0.0001). The mean (SD) peak expiratory intrapleural pressures were 5.4 (2.7), 13.5 (6.2) and 10.3 (8.5) cmH(2)O, respectively (p<0.0001). At autopsy, no rib, intra-abdominal or intra-thoracic injury was observed. CONCLUSION: Lateral chest and abdominal thrust techniques generated significantly greater airway and pleural pressures than the anterior thrust technique. We recommend further research to provide additional evidence that may inform management guidelines for clearing foreign body upper airway obstruction.

Concepts: Sternum, Pressure, Thorax, Obstructive lung disease, Pleural cavity, Victim, Thrust, Pressure sensor

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BACKGROUND: Situs inversus totalis represents an unusual anomaly characterized by a mirror-image transposition of the abdominal and thoracic viscera. It often occurs concomitantly with other disorders that make difficult diagnosis and management of abdominal pathology. The relationship between situs inversus totalis and cancer remains unclear. CASE PRESENTATION: We describe a 33-year old Guinean man with situs inversus totalis who presented with obstructive jaundice. Imaging and endoscopic modalities demonstrated a mass of distal common bile duct which biopsy identified an adenocarcinoma. The patient was successfully treated by cephalic pancreaticoduodenectomy followed by adjuvant chemoradiation and he is doing well without recurrence 8 months after surgery. CONCLUSION: The occurrence of bile duct adenocarcinoma in patient with situs inversus totalis accounts as a rare coincidence. In this setting, when the tumor is resectable, surgical management should be considered without contraindication and must be preceded by a careful preoperative staging.

Concepts: Cancer, Digestive system, Liver, Hepatology, Abdomen, Thorax, Situs inversus, Gallstone

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We herein report a case of primary marginal zone lymphoma (MZL) of the posterior mediastinum in an 84-year-old woman. Computed tomography of the chest showed a posterior mediastinal mass in the right thoracic paravertebral region with right pleural effusion. Pathological findings of a surgical biopsy from the posterior mediastinum, along with immunohistochemical and flow cytometric results, indicated MZL. The patient was treated with chemotherapy and radiation therapy for the mediastinal lesion and achieved complete remission. A relapse occurred 3 months after the initial treatment regimen. However, a second relapse has not occurred more than 2 years after second-line chemotherapy. This is the first case of MZL originating in the posterior mediastinum.

Concepts: Cancer, Heart, Chemotherapy, Thorax, Mediastinal tumor, Mediastinum, Thoracic cavity, Posterior mediastinum

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The Heimlich manoeuvre is a well-known intervention for the management of choking due to foreign body airway occlusion, but the evidence base for guidance on this topic is limited and guidelines differ. We measured pressures during abdominal thrusts in healthy volunteers. The angle at which thrusts were performed (upthrust vs circumferential) did not affect intrathoracic pressure. Self-administered abdominal thrusts produced similar pressures to those performed by another person. Chair thrusts, where the subject pushed their upper abdomen against a chair back, produced higher pressures than other manoeuvres. Both approaches should be included in basic life support teaching.

Concepts: Person, Subject, Abdomen, Thorax, First aid, Rocket, Human abdomen, Henry Heimlich

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The turtle shell is a complex structure that currently serves a largely protective function in this iconically slow-moving group [1]. Developmental [2, 3] and fossil [4-7] data indicate that one of the first steps toward the shelled body plan was broadening of the ribs (approximately 50 my before the completed shell [5]). Broadened ribs alone provide little protection [8] and confer significant locomotory [9, 10] and respiratory [9, 11] costs. They increase thoracic rigidity [8], which decreases speed of locomotion due to shortened stride length [10], and they inhibit effective costal ventilation [9, 11]. New fossil material of the oldest hypothesized stem turtle, Eunotosaurus africanus [12] (260 mya) [13, 14] from the Karoo Basin of South Africa, indicates the initiation of rib broadening was an adaptive response to fossoriality. Similar to extant fossorial taxa [8], the broad ribs of Eunotosaurus provide an intrinsically stable base on which to operate a powerful forelimb digging mechanism. Numerous fossorial correlates [15-17] are expressed throughout Eunotosaurus' skeleton. Most of these features are widely distributed along the turtle stem and into the crown clade, indicating the common ancestor of Eunotosaurus and modern turtles possessed a body plan significantly influenced by digging. The adaptations related to fossoriality likely facilitated movement of stem turtles into aquatic environments early in the groups' evolutionary history, and this ecology may have played an important role in stem turtles surviving the Permian/Triassic extinction event.

Concepts: Evolution, Turtle, Reptile, Thorax, Rib, Human rib cage, Anapsid, Carapace

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The genesis of cardiogenic oscillations, i.e. the small waves in airway pressure (COS(paw)) and flow (COS(flow)) signals recorded at the airway opening is under debate. We hypothesized that these waves are originated from cyclic changes in pulmonary artery (PA) pressure and flow but not from the physical transmission of heartbeats onto the lungs. The aim of this study was to test this hypothesis. In 10 anesthetized pigs, COS were evaluated during expiratory breath-holds at baseline with intact chest and during open chest conditions at: (1) close contact between heart and lungs; (2) no heart-lungs contact by lifting the heart apex outside the thoracic cavity; (3) PA clamping at the main trunk during 10 s; and (4) during manual massage after cardiac arrest maintaining the heart apex outside the thorax, with and without PA clamping. Baseline COS(paw) and COS(flow) amplitude were 0.70 ± 0.08 cmH(2)O and 0.51 ± 0.06 L/min, respectively. Both COS amplitude decreased during open chest conditions in step 1 and 2 (p < 0.05). However, COS(paw) and COS(flow) amplitude did not depend on whether the heart was in contact or isolated from the surrounding lung parenchyma. COS(paw) and COS(flow) disappeared when pulmonary blood flow was stopped after clamping PA in all animals. Manual heart massages reproduced COS but they disappeared when PA was clamped during this maneuver. The transmission of PA pulsatilty across the lungs generates COS(paw) and COS(flow) measured at the airway opening. This information has potential applications for respiratory monitoring.

Concepts: Blood, Lung, Heart, Chest, Vein, Pulmonary artery, Thorax, Thoracic cavity

28

STUDY DESIGN.: Prospective case series study. OBJECTIVE.: To study the effect of percutaneous thoracoplasty-only procedure on curve pattern in mature adolescent idiopathic scoliosis (AIS). SUMMARY OF BACKGROUND DATA.: The rib hump prominence on the convex side is the major cosmetic concern among patients with AIS. Thoracoplasty combined with spinal fusion is a commonly used procedure in scoliosis. However, there are no studies regarding the effect of isolated thoracoplasty procedure on curve pattern in skeletally matured patients with AIS. METHODS.: The study involved 7 skeletally matured female patients with AIS. The convex rib hump deformity was measured preoperatively using hump height and hump angle. We performed thoracoplasty without spinal fusion in patients with the Cobb angle less than 40° but with prominent hump deformity. Thoracoplasty was performed percutaneously using 1 or 2 transverse incisions along the rib hump, and apex portions of the deformed ribs were resected. The Cobb angle was measured before surgery, immediately after surgery, and at final follow-up visit. In all cases, clinical satisfaction was assessed using the Scoliosis Research Society Instrument (SRS-22 questionnaires) and trunk appearance perception scale before surgery and at final follow-up visit. RESULTS.: The mean patient age was 20.24 years and an average of 4 ribs were resected. The mean preoperative hump height and hump angle of 38.14 mm and 14.14° improved to 11.70 mm and 11.42° respectively, after surgery (P = 0.018 and 0.042). Preoperative and the final follow-up mean Cobb angles were 35.43° and 45.00°, respectively (P = 0.028). On average, the mean thoracic curve progressed by 9.57°. Preoperative Scoliosis Research Society Instrument SRS-22 questionnaires and trunk appearance perception scale scores of 4.09 and 2.57 respectively improved to and 4.26 and 3.66 after surgery (P = 0.126 and 0.014). CONCLUSION.: Percutaneous thoracoplasty-only procedure gives significant rib humps correction and satisfactory clinical outcome. However, progression of the curve was observed after surgery. This suggests that the convex ribs function as a buttress for curve progression.

Concepts: Vertebral column, Scoliosis, Arithmetic mean, Paul Randall Harrington, Scoliosis Research Society, Thorax, Spinal fusion, Case series

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BACKGROUND: In this paper a new non-invasive, operator-free, continuous ventricular stroke volume monitoring device (Hemodynamic Cardiac Profiler, HCP) is presented, that measures the average stroke volume (SV) for each period of 20 seconds, as well as ventricular volume-time curves for each cardiac cycle, using a new electric method (Ventricular Field Recognition) with six independent electrode pairs distributed over the frontal thoracic skin. In contrast to existing non-invasive electric methods, our method does not use the algorithms of impedance or bioreactance cardiography. Instead, our method is based on specific 2D spatial patterns on the thoracic skin, representing the distribution, over the thorax, of changes in the applied current field caused by cardiac volume changes during the cardiac cycle. Since total heart volume variation during the cardiac cycle is a poor indicator for ventricular stroke volume, our HCP separates atrial filling effects from ventricular filling effects, and retrieves the volume changes of only the ventricles. METHODS: In-vitro experiments on a post-mortem human heart have been performed to measure the effects of increasing the blood volume inside the ventricles in isolation, leaving the atrial volume invariant (which can not be done in-vivo). These effects have been measured as a specific 2D pattern of voltage changes on the thoracic skin. Furthermore, a working prototype of the HCP has been developed that uses these in-vitro results in an algorithm to decompose voltage changes, that were measured in-vivo by the HCP on the thoracic skin of a human volunteer, into an atrial component and a ventricular component, in almost real-time (with a delay of maximally 39 seconds). The HCP prototype has been tested in-vivo on 7 human volunteers, using G-suit inflation and deflation to provoke stroke volume changes, and LVot Doppler as a reference technique. RESULTS: The in-vitro measurements showed that ventricular filling caused a pattern over the thorax quite distinct from that of atrial filling. The in-vivo tests of the HCP with LVot Doppler resulted in a Pearson’s correlation of R = 0.892, and Bland-Altman plotting of SV yielded a mean bias of -1.6 ml and 2SD = 14.8 ml. CONCLUSIONS: The results indicate that the HCP was able to track the changes in ventricular stroke volume reliably. Furthermore, the HCP produced ventricular volume-time curves that were consistent with the literature, and may be a diagnostic tool as well.

Concepts: Blood, Heart, Measurement, Atrial fibrillation, Chest, Thorax, Thoracic cavity, Stroke volume

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BACKGROUND:: Slipping rib syndrome (SRS) is a musculoskeletal cause of severe and recurrent thoracic or abdominal pain. The etiology of SRS is unknown, it seems to arise from costal hypermobility with a tendency of one of the ribs (usually from 8th to 10th but also 11th and 12th have been described) to slip under the superior adjacent rib. Its prevalence is underestimated because SRS is mainly a clinical diagnosis, frequently missed. The critical aspect of the diagnosis is knowledge of the condition itself, which, when lacking, often results in the patient being referred to many different specialists and exposed to unnecessary and costly investigations. The management of the condition includes conservative techniques such as manipulation, localized anesthetic, and steroid or anesthetic nerve block. However, where conservative therapy fails, surgical treatment, with excision of the rib, may be performed. METHODS:: In this paper we describe the case of a patient with persistent and debilitating flank pain who, after many investigations, was diagnosed with SRS. RESULTS:: The usual conservative treatment failed, after which we treated the patient with injections of incobotulinumtoxin A into muscles inserting on the inferior side of the rib cage (quadratus lumborum muscle, muscle transversus abdomini, abdominal external oblique muscle, and recto abdomini) achieving a complete relief from pain. CONCLUSIONS:: To our knowledge botulinum toxin has never been proposed before for the treatment of SRS. We believe that it should be considered as a therapeutic option, especially where other medical treatments have failed or as an intermediate step before surgical intervention.

Concepts: Abdomen, Thorax, Rib, Human rib cage, Iliac crest, Abdominal external oblique muscle, Muscles of the torso, Quadratus lumborum muscle

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ABSTRACT BACKGROUND: Radio-opaque markers (otherwise known as fiducials) are utilized clinically to mark sites of biopsy or resection, which aids with targeting of local therapy, including surgery and radiation therapy. We performed a human cadaveric imaging series using a novel injectable, radio-opaque absorbable hydrogel marker to demonstrate its potential in the management of thoracic malignancies. METHODS: Baseline CT images were performed on three unfixed cadaveric specimens. Hydrogel marker implants were placed in the submucosa of the esophagus, the mediastinum and lung parenchyma by an endoscopic approach with real-time endobronchial and esophageal ultrasound guidance. Sub-pleural implants in peripheral lung parenchyma were also performed via an anterolateral thoracotomy. Post-implant simulation CT, T2-MRI and cone-beam CT were performed. Gross dissection of the lung parenchyma was used to evaluate localization of the hydrogel. RESULTS: Transthoracic and endoscopic marker placements were readily achieved. The hydrogel appeared hyperechoic by ultrasound, hyper-enhancing on T2-MRI imaging, and demonstrated radio-opacity of approximately 300 HU in simulation CT and cone-beam CT. Gross dissection of the lung revealed well-localized blebs of hydrogel marker within lung parenchyma. CONCLUSIONS: This cadaveric series demonstrates the excellent visibility of a radio-opaque injectable hydrogel marker in the human thorax by multiple common imaging techniques. The hydrogel marker forms a well-localized bleb within tissue, which can assist with triangulation of disease during minimally invasive thoracic surgery. Esophageal applications include radiographic delineation of tumor defined by endoscopy, and image guidance for radiotherapy. Future in-vivo studies are warranted, because radiopaque injectable compounds are promising alternatives to metal fiducials.

Concepts: Cancer, Ionizing radiation, Lung, Surgery, Radiation therapy, Demonstration, Thorax, Esophagus