Respiratory Management Following Spinal Cord Injury - 19

CLINICAL PRACTICE GUIDELINE

ventilator for the group of 52 people was 83%. PVFB was found to be more successful when weaning was attempted early after injury, and it was more successful when weaning was first attempted longer than one month post injury. Also, 71% (12 of 17) of the individuals who had failed IMV weaning were able to completely wean by the PVFB method. Four patients were discharged on partial weans, and only one was discharged on full-time ventilation. Gardner et al. (1986) noted that “spontaneous respiration of oxygen-enriched humidified air for graded periods is more comfortable because their lack of…muscle power impairs their ability to overcome the…resistance and phase lag of most ventilators.”

Partial Weaning
Partial weaning using PVFB has the following advantages: It allows the patient’s cuff to be deflated. By using a one-way speaking valve the person can talk while weaning (unless diagnosed with tracheal stenosis, which prevents air from moving around the tube and over the vocal cords; in this case, the one-way speaking valve cannot be used). It allows the patient to leave home without the ventilator for activities, if able to wean for a matter of hours. It allows the patient to be off the ventilator for transfer from bed to chair for bathing, tracheostomy changes, or tracheostomy care. It allows a measure of safety in the case of a power failure. If IMV is used as the long-term ventilator protocol, the patient will not be able to speak or leave home without the ventilator.

neck, while recording from the diaphragm on each side, will reveal whether any muscle contraction may be recordable. High frequency electrical stimulation of each phrenic nerve with simultaneous fluoroscopy of the corresponding diaphragm will reveal whether there is perceptible movement of each side. Such testing will also reveal whether the stimulation is painful to the patient. If there is a strong contraction of each leaf of the diaphragm, the patient is a candidate for implantation of bilateral phrenic nerve pacers. After a postoperative recovery period, a progressive electrical exercise program is begun. The goal is to recondition each leaf of the diaphragm to regain strength and endurance of the diaphragmatic musculature to allow progressively longer periods of ventilation using the diaphragm alone. Vital capacity may be measured with electrical stimulation. As with progressive ventilator-free breathing for weaning, a falling vital capacity may indicate diaphragm fatigue. Various authors have debated whether alternating single diaphragm stimulation will allow longer periods of electrophrenic ventilation. Simultaneous stimulation of each phrenic nerve seems to give more efficient ventilation. Duration of electrophrenic respiration each day may exceed 16 hours out of 24, with the patient “resting” on a positive pressure ventilator overnight. This period of rest allows physiologic recovery of the diaphragmatic muscle in anticipation of the next day’s use. To benefit from electrophrenic respiration, a patient must have healthy lungs that are free of pneumonia, atelectasis, and excessive secretions. Family education and troubleshooting are the keys to the confident use of this technology in the home setting. Access to technological support and medical expertise for followup is crucial to the long-term success of electrophrenic respiration. 20. Consider the advantages of acute and longterm use of noninvasive ventilation over initial intubation and long-term tracheostomy if the treatment staff has the expertise and experience in the use of such devices.
(Scientific evidence–V; Grade of recommendation–C; Strength of panel opinion–Strong)

Electrophrenic Respiration
19. For apneic patients, consider evaluation for electrophrenic respiration.
(Scientific evidence–V; Grade of recommendation–C; Strength of panel opinion–Strong)

Diaphragmatic contraction and ventilation may be restored if the spinal cord injury is above the anterior horn cells of roots C3, C4, and C5 (the phrenic nucleus). Patients are candidates for pacemaker implantation if they are apneic and have viable phrenic nerves (Glenn et al., 1976). A nerve stimulation test of the phrenic nerve in the

Patients with acute spinal cord injury who present with respiratory distress are almost all intubated to accommodate mechanical ventilation, and the majority of people who require long-term mechanical ventilation have a tracheostomy placed unless they are in a medical center that has expertise in noninvasive ventilation. There are advantages, however, for the patient to avoid initial

Respiratory Management Following Spinal Cord Injury

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