High cervical medullary injury (C1-4) is a fatal trauma that, in addition to causing severe quadriplegia, often involves the respiratory center in the spinal cord (phrenic nerve, C3-5), resulting in severe respiratory dysfunction in the patient. Extensive respiratory muscle paralysis, in addition to directly causing inadequate pulmonary ventilation, also causes coughing and sputum expulsion weakness. It further leads to the inability of airway secretions to be effectively cleared, and patients are susceptible to secondary complications such as pulmonary atelectasis and pneumonia. In the acute phase, 84% of patients with cervical medullary injury have respiratory complications, 20% are treated with tracheotomy and mechanical ventilation, and finally 4-5% of patients with severe high level cervical medullary injury require lifelong ventilation support. Effective removal of abnormal secretions from the airway, improvement of pulmonary ventilation, and respiratory rehabilitation are three important elements in the management of respiratory dysfunction in high cervical spinal cord injury. Removal of abnormal secretions from the respiratory tract By giving the patient frequent turning, patting the back and assisting in sputum removal, the patient can help to remove secretions from the respiratory tract and prevent pulmonary complications. However, in the acute phase, the most effective way to remove secretions from the airway in patients with cervical medullary injury is to perform a tracheotomy. Although tracheotomy treatment brings new trauma and pain (restricted feeding, speech, etc.), it has at least three advantages: effective removal of secretions through an intra-incisional cannula; ease of care; and the ability to provide, reliable long-term use of mechanical ventilation access. Therefore tracheotomy technique is being more and more widely used in patients with cervical medullary injury. In addition to its own advantages, it is related to the development of cervical internal fixation techniques in recent years. For tracheotomy patients, posterior cervical spine surgery can be performed to stabilize the cervical spine. For patients after anterior cervical surgery, tracheotomy can also be performed immediately if needed and with a low infection rate. Maintenance of ventilation methods Patients with cervical medullary injury, without spontaneous breathing, or with residual ventilation that cannot maintain basal metabolic level requirements, must be given a ventilator to provide assisted ventilation. In patients with severe high cervical medullary injuries, tracheotomy with mechanical ventilation is an essential management measure to ensure the life of the patient in the acute phase. In patients with complete diaphragmatic paralysis, lifelong ventilator support is required. Respiratory reconstruction Clinical observations show that patients who survive acute high cervical medullary injury at the accident scene have nerve injury planes below C2, and in such patients, the paramedian nerve (C1-2 range) is largely preserved. The paramedian nerve innervates the trapezius muscle and the sternocleidomastoid muscle. It is an auxiliary inspiratory muscle. We have developed two surgical techniques to reestablish respiratory function using the function of the paraspinal nerve, with excellent results: 1. Replacement of the paraplegic phrenic nerve by a transfer of the oblique muscle branch of the paraspinal nerve: Our clinical studies have shown that the transferred paraspinal nerve can effectively drive the diaphragm by synchronizing training with inspiration. However, there are two problems with this technique that limit its widespread use: firstly, phrenic nerve replacement is a slow process that takes at least 6 months; secondly, the optimal surgical time for nerve transfer replacement is 3-6 months after nerve injury, which is also the best window for spontaneous recovery from spinal cord injury. Premature surgery risks destroying the phrenic nerve with spontaneous recovery potential, and late repair will result in poor nerve Poor replacement effect. 2.Use the function of the paramedian nerve to rebuild thoracic breathing: The paramedian nerve innervates the trapezius muscle, which ends at the scapular post and has the function of lifting the scapula and aiding inspiration through the muscles attached to the scapula and rib cage (such as the anterior serratus). However, in patients with cervical marrow injury, because most of the muscles attached to the scapula are paralyzed, the scapula slides upward along the thorax when the rhomboid muscle contracts, and its auxiliary inspiratory effect, basically, is abolished. We use the subscapularis to suspend the rib cage, transfer the force of the trapezius muscle to the thorax, and rebuild the thoracic respiratory power in patients with high cervical medullary injury. This technique can improve the respiratory function in three aspects. The trapezius muscle is a powerful auxiliary inspiratory muscle that establishes a synchronous activity pattern with the diaphragm and provides thoracic respiratory power; suspending the 6th-8th posterior ribs exerts a traction force on the inferior chest wall to counteract the soft tissue invagination of the chest wall caused by negative thoracic pressure during inspiration; increasing the circumference of the area where the diaphragm attaches to the chest wall strengthens the diaphragm initiation point support and improves the efficiency of diaphragmatic work. This technique improves the patient’s respiratory function, improves coughing and sputum evacuation, reduces pulmonary complications; shortens the patient’s ventilator use time, and even takes some ventilator-dependent patients off the ventilator. Diaphragm pacemaker (electrical stimulation technique) treatment There are three main methods to restore respiratory function using electrical stimulation technique: 1. Electrical stimulation of the phrenic nerve technique: tiny electrodes can be placed on the phrenic nerve in the neck through a surgical access to the neck. The procedure is simple, and it is easy to replace the electrode again after the electrode fails. The disadvantage is that the paraphragmatic nerve cannot be included; the thoracic route can also be used to place electrodes to stimulate the thoracic phrenic nerve, which has a higher success rate and stimulation effect because the electrodes are placed in the thoracic phrenic nerve after the merger of the paraphragmatic and phrenic nerves. In recent years, the use of thoracoscopic placement of electrodes has been widely promoted as it makes the surgery less invasive and simple, but the problem is that it is difficult to replace the electrodes after they fail. 2.Electrical stimulation of the diaphragm technique: Using laparoscopy, multiple electrodes are fixed at the point of phrenic nerve into the muscle, and the signal is transmitted through the muscle with higher energy to stimulate the adjacent phrenic nerve. This technique is simple, less traumatic, and has no potential risk of damaging the phrenic nerve, but the stimulation effect, at least in theory, is better than the direct stimulation bear effect of the phrenic nerve. 3, electrical stimulation of the intercostal nerve technique: very unfortunately, in clinical practice, the application of electrical stimulation of the phrenic nerve technique is limited. The main reason is: patients with acute spinal cord injury with respiratory dysfunction, due to phrenic nerve cell body injury (C3-5), only very few patients are suitable for the procedure, so some people try intercostal nerve electrical stimulation technique, this technique is to partially restore thoracic breathing by stimulating the intercostal nerve to agitate the contraction of the external intercostal muscles, the clinical effect is subject to further observation. The most effective respiratory training method for patients with high cervical spinal cord injury is the rehabilitation of inspiratory muscles, and the value of expiratory muscle training is very limited. The effect of respiratory rehabilitation training for patients with cervical spinal cord injury is significant, improving lung function and reducing pulmonary complications. In the acute phase, residual diaphragm function training is a key component, but it has been debated whether this improvement in lung function is the effect of reinforcement of residual diaphragm training or the result of spontaneous recovery after spinal cord injury. If recovery of diaphragmatic function depends primarily on spontaneous recovery from spinal cord injury, then intensive diaphragmatic training during the acute phase (e.g., adding weight to the abdomen during the acute phase) may be detrimental. This is because diaphragmatic activity is a continuous rhythmic activity, and for the residual diaphragm, it is constantly active under a high load in an emergency mode in order to maintain respiratory function, and intensive diaphragmatic training tolerance can easily lead to diaphragmatic fatigue. However, in patients with high cervical spinal cord injury, it is important to use the paraspinal innervated muscles to improve the patient’s respiratory function and help the patient get off the ventilator. The sternocleidomastoid muscles are trained to contract in concert with the residual diaphragm. This synchronized activity provides thoracic respiratory power by lifting the sternum and first rib from the anterior chest; in addition, when muscle tone occurs in the muscles around the scapulae in the thoracic back, contraction of the paraneoplastic innervated trapezius muscle can provide partial thoracic respiratory power by lifting the scapulae and the myofascial structures attached to the thorax. Our experience is that most patients with intact paraspinal nerve function and a small residual diaphragm function can be taken off the ventilator through rehabilitation or surgery.