Principles of Fetal Surgery

Fetal therapy (in utero therapy) is a type of special therapy which aims to prevent or correct congenital anomalies in fetus, and prevents their severe consequences on later fetal development. It includes the use of in utero human fetal stem cell transplantation, fetal gene therapy and gene-editing technology as a new treatment for fetal genetic disorders. It started with open fetal surgery and then significantly advancing with innovations, toward minimally invasive fetal procedures, which are undoubtedly the future of fetal surgery, with the goal of providing the best possible fetal outcome, while minimizing the morbidity and mortality to the mother. The goal of fetal treatments is to decrease both fetal and maternal risks and prevent premature rupture of membranes. Fetal ultrasound and MRI are crucial for successful fetal interventions. Moreover, multidisciplinary fetal teams, including fetal surgeon, ultrasonographer, perinatologist, and anesthesiologist, are essential for optimum care to both mother and fetus. Finally, any new modality of fetal therapy must be thoroughly evaluated in animal models before clinical practice. In this chapter, we discuss the basic principles of fetal surgery, milestones of fetal surgery, specific fetal anomalies that are amenable for fetal surgery, successful fetal surgery criteria and future of fetal surgery

Long-Term Complications of Tracheal Intubation

Endotracheal intubation is an intervention frequently performed in the hospital setting in order to protect the central airway and provide mechanical support of ventilation. Many health care providers are expected to be able to intubate the patients for different indications. As the case in any medical intervention, endotracheal intubation can cause complications. These complications are categorized as early or late according to the time of onset of the presenting symptoms. This chapter will discuss the long term complications of endotracheal intubation that might be encountered by the treating physicians. The chapter will stress on the predisposing factors for these complications and the available methods to avoid and treat them

Assessing changes in airflow and energy loss in a progressive tracheal compression before and after surgical correction

The energy needed to drive airflow through the trachea normally constitutes a minor component of the work of breathing. However, with progressive tracheal compression, patient subjective symptoms can include severe breathing difficulties. Many patients suffer multiple respiratory co-morbidities and so it is important to assess compression effects when evaluating the need for surgery. This work describes the use of computational prediction to determine airflow resistance in compressed tracheal geometries reconstructed from a series of CT scans. Using energy flux analysis, the regions that contribute the most to airway resistance during inhalation are identified. The principal such region is where flow emerging from the zone of maximum constriction undergoes breakup and turbulent mixing. Secondary regions are also found below the tongue base and around the glottis, with overall airway resistance scaling nearly quadratically with flow rate. Since the anatomical extent of the imaged airway varied between scans - as commonly occurs with clinical data and when assessing reported differences between research studies - the effect of sub-glottic inflow truncation is considered. Analysis shows truncation alters the location of jet breakup and weakly influences the pattern of pressure recovery. Tests also show that placing a simple artificial glottis in the inflow to a truncated model can replicate patterns of energy loss in more extensive models, suggesting a means to assess sensitivity to domain truncation in tracheal airflow simulations

Biocompatibility Of Magnesium-Based Biomaterials For Airway Stent Applications

Tracheomalacia, stenosis and other traumatic airway injuries (e.g., obstructive tracheobronchial tumors) often require airway stenting. Traditional polymeric stents are prone to cause infection, do not ‘grow’ with a child and often require surgical removal. Therefore, resorbable biometallics are ideal materials for tracheal stent devices. Magnesium (Mg) is an attractive material because of its biocompatibility, abundance within the human body, and intrinsic corrosive nature can be overcome via alloying elements. We hypothesize that resorbable magnesium-based materials can be utilized for the development of tracheal stents. The objective of the present study was to determine cytocompatibility of Mg alloys with fully differentiated cultures of normal human bronchial epithelial (NHBE) cells to simulate an in vivo response. Confluent cultures of differentiated NHBE cells were exposed to wires of high purity Mg or novel MgZnCa alloy for 0,4,18, 24, and 48 hours. Endpoint assays included reverse transcriptase PCR, western blot analysis, and ELISA to assess modulation of cellular responses such as regulation of inflammatory mediators and mucus secretion; wire corrosion was evaluated via scanning electron microscopy. A wound repair assay was performed to evaluate the effect of wires on cell proliferation. One-way analysis of variance (ANOVA) and Bonferroni post-test corrections (p value\u3c0.05) were performed to detect differences among means. Wires of MgZnCa did not elicit inflammation, inhibit cell proliferation or migration; and degraded less than Mg wires. These findings suggest MgZnCa alloy may be an acceptable biomaterial to use in the application of tracheal stents; however, further analysis is required to determine long-term stent-airway dynamics

Functional Anatomy and Physiology of Airway

In this chapter, we scope the importance of functional anatomy and physiology of the upper airway. The upper airway has an important role in transporting air to the lungs. Both the anatomical structure of the airways and the functional properties of the mucosa, cartilages, and neural and lymphatic tissues influence the characteristics of the air that is inhaled. The airway changes in size, shape, and position throughout its development from the neonate to the adults. Knowledge of the functional anatomy of the airway in these forms the basis of understanding the pathological conditions that may occur. The upper airway extends from the mouth to the trachea. It includes the mouth, the nose, the palate, the uvula, the pharynx, and the larynx. This section also describes the functional physiology of this airway. Managing the airway of a patient with craniofacial disorders poses many challenges to the anesthesiologist. Anatomical abnormalities may affect only intubation, only airway management, or both. This section also focuses on the abnormal airways in obesity, pregnancy, children and neonate, and patients with abnormal facial defects

Diseases of the Chest, Breast, Heart and Vessels 2019-2022

This open access book focuses on diagnostic and interventional imaging of the chest, breast, heart, and vessels. It consists of a remarkable collection of contributions authored by internationally respected experts, featuring the most recent diagnostic developments and technological advances with a highly didactical approach. The chapters are disease-oriented and cover all the relevant imaging modalities, including standard radiography, CT, nuclear medicine with PET, ultrasound and magnetic resonance imaging, as well as imaging-guided interventions. As such, it presents a comprehensive review of current knowledge on imaging of the heart and chest, as well as thoracic interventions and a selection of "hot topics". The book is intended for radiologists, however, it is also of interest to clinicians in oncology, cardiology, and pulmonology