Additional relief can be obtained by stitching the lateral wall of the aorta to the adjacent rib to pull it away from the esophagus.After insertion of a chest tube to prevent hemothorax and/or pneumothorax, the fourth and fifth rib are approximated by an absorbable suture. The surgery is completed by closure of the left thoracotomy wound in layers.In most centers, the mortality risk for surgery is between zero and 2%. A specific risk of open surgical repair of double aortic arch is injury to the recurrent laryngeal nerve, which can cause vocal cord paralysis. Injury to the lymphatic system can lead to postoperative chylothorax. Additional risks include lung injury, bleeding with the need for blood transfusions and wound infection. Postoperative care
After the surgery, some patients require intubation and mechanical ventilation for several days to allow adequate tracheal toilet, but most patients can have the tubes removed soon after the surgery. The obstructive airway symptoms may be worse in the first postoperative weeks. Only a few patients have immediate relief of stridor, but many obtain immediate relief of problems with swallowing (dysphagia). After extubation, it might be necessary to maintain positive airway pressure by appropriate flows of a humidified oxygen/air mixture. Epidemiology
Complete vascular rings represent about 0.5-1% of all congenital cardiovascular malformations. The majority of these are double aortic arches. There is no known gender preference, i.e. males and females are about equally affected. There is also no known ethnic or geographic disposition.Associated cardiovascular anomalies are found in 10-15% of patients.
Although up to 2% of the cells die most migrate from the blood to the tissues, mainly the intestines and lungs, where pathogens are most likely to be encountered.Some monocytes leave the blood circulation and migrate to the muscles where they differentiate and become macrophages. These cells differentiate into two types: proliferative macrophages, which are responsible for increasing the number of stem cells  and restorative macrophages, which are involved their maturing to muscle cells. Repair and regeneration
The immune system, particularly the innate component, plays a decisive role in tissue repair after an insult. Key actors include macrophages and neutrophils, but other cellular actors, including γδ T cells, innate lymphoid cells (ILCs), and regulatory T cells (Tregs), are also important. The plasticity of immune cells and the balance between pro-inflammatory and anti-inflammatory signals are crucial aspects of efficient tissue repair. Immune components and pathways are involved in regeneration as well, for example in amphibians such as in axolotl limb regeneration. According to one hypothesis, organisms that can regenerate (e.g., axolotls) could be less immunocompetent than organisms that cannot regenerate. Disorders of human immunity
Failures of host defense occur and fall into three broad categories: immunodeficiencies, autoimmunity, and hypersensitivities. Immunodeficiencies
Immunodeficiencies occur when one or more of the components of the immune system are inactive. The ability of the immune system to respond to pathogens is diminished in both the young and the elderly, with immune responses beginning to decline at around 50 years of age due to immunosenescence.