Vol. 14 •Issue 17 • Page 24
Ventilator Management of Spinal Cord Patients * Ventilator Management of Spinal Cord Patients
By Charles O’Donnell, MS, RRT, and Margaret A. Clark, BA, RN, RRT
During the 1950s, the iron lung was the only option available for mechanical ventilation and was used to handle everyone from polio to spinal cord injured patients. We’ve come a long way in 50 years. Polio is all but extinct and today’s spinal cord injured (SCI) patients have new technologies to support them. But caregivers trying to successfully apply these new technologies to SCI patients must have skills and knowledge not just of the machines, but also of the special needs of the patients. Weaning a SCI patient, for example, requires its own set of rules.
Many spinal cord injuries are the result of risky behaviors (motor vehicle or diving accidents) and involve young previously health individuals. These patients are usually relatively hemodynamically stable and do not have gas exchange problems once they get beyond their acute injury stage. Primarily it is their respiratory mechanics that are the issue. SCIs directly impacts respiratory muscle function. Clinically, muscle paralysis causes a decrease in volume and a loss of abdominal support required for effective coughing.
The degree of impairment is dependent on the level of the injury, of course. The diaphragm provides approximately 40 percent of the work of tidal volume breathing in a healthy individual. In cervical spinal cord injuries, since the intercostals are paralyzed, the diaphragm is forced to assume 100 percent of the work of breathing. As a result, strengthening the diaphragm through endurance training is an important aspect of a successful wean. Diaphragmatic weight training is highly beneficial for many patients, particularly the elderly or debilitated.
Injuries at the C-1 and C-2 levels result in paralysis of the phrenic nerve and all the respiratory musculature. These individuals are unable to move their diaphragm and their intercostals. If their phrenic nerve is intact, they may be assessed for placement of a phrenic nerve stimulator. These individuals will require full mechanical ventilation for their respiratory support. Often times “Safety Weans” are attempted in this group. A safety wean requires the strengthening of the individual’s respiratory assessory muscles to permit the patient to breath on his own for a few minutes in the event he is disconnected from a ventilator.
Injuries at the C-3 level usually result in partial damage to the phrenic nerve. These patients may experience hemidiphragmatic paralysis. With proper training of their accessory muscles and their remaining functional diaphragm, these individuals may be able to develop independence from the ventilator for short periods of time.
RESPIRATORY PARADOX
Injuries at the C-4 level can be a paradox from the respiratory perspective. On inspiration, the diaphragm performs as usual. The paralysis of the intercostal muscles, however, results in the paradoxical collapse of the chest wall on inhalation. These patients can ventilate themselves and will usually be able to wean from the ventilator if they are taught effective cough and secretion management skills.
Spinal cord injuries in the C-5 to T-5 zone usually result in varying level sof paralysis of the intercostal muscles. These individuals can ventilate themselves adequately and will wean from the ventilator. The challenge for them is to prevent atelectasis and mobilize secretions. Coughing is weak, ineffective, or absent because of the paralysis of the abdominal muscles. Practitioners can help these patients develop more effective coughing methods by using the In- exsufflator or a quad cough technique.
Injuries below T-5 do not directly impact the respiratory system, but individuals with injuries at these levels may have some or total impairment of their abdominal muscles.
Psychosocial issues and depression are common among SCI patients. As practitioners, we may find ourselves interacting directly with social services, psychiatric services and the patient’s family. It is important that we understand the individual’s frame of mind and that of the family as we proceed with ventilator management.
Conflicting messages from caregivers can be frustrating for both the patient and family members. For example, there is no point in telling patients we are working to get them off their ventilators when nerosurgeons confirm there is no hope of that happening. Conversely, it is important to coax along those patients who do not believe they can wean from a ventilator if there are indications they can.
Other patients, depending on their injuries, may be able to support themselves for several hours during the day on a trach collar if they cannot come off the vent completely. Basically we need to roll up our sleeves and get into a patient’s chart and take an active role in the care team process. We need also to remember we can coordinate our efforts with speech therapy and help patients express their opinions through vocalization even while they are still on the ventilator.
ISOLATION
One psychosocial dynamic often overlooked is isolation. Many SCI patients spend weeks and even months in a hospital. This does not mean they need to be in a room alone. Today’s technology permits ventilator-dependent patients to be completely mobile via a wheelchair. In fact, mobility is a milestone in their rehab progression.
The next step is mastering the technology. Patients who can direct their own care can transition from a medical care environment to home care. Among things they need to know: how to identify when ventilator batteries are getting low or when they can benefit from suctioning.
In the typical rehab setting, respiratory care is just one of many disciplines, and fitting respiratory services and assessments in and around physical, occupational and speech therapy and social services can be tough. But it is essential.
Here are a few hints to help you in your job. It is great if respiratory does its mechanics measurements in the morning while the rest of the staff is still in shift report. At this time of the day, the patient is quiet and rested and likely to do well. These measurements can be a good baseline reading of the patient’s status.
Of course, you also need to determine whether they are an accurate reflection of abilities. Will the numbers repeat at 2 p.m. after the individual has been sitting up in the chair for six hours? Will the patient desaturate during PT?
Reassessing at these times may give a different clinical picture. The goal of any rehab program is to enhance the individual’s abilities to perform activities of daily living and to restore them to full functionality if possible. Team and family meetings are a great way to set goals and assess progress.
DO YOU KNOW THESE?
Quick questions for you.
What home ventilators provide pressure support?
What devices are available to strengthen respiratory musculature?
What devices assist in secretion mobilization and coughing?
Most of us hospital-based practitioners are guilty of not keeping up with the latest and greatest in the home care arena. Yet these are the devices our SCI patients will have available to them. Brush up a little and learn what’s out there! Involve the home care therapist early to assure the smoothest transition possible for the patient.
Once the spinal cord injury has been stabilized, respiratory care’s goal is to assess the individual’s level of functioning and begin maximizing capabilities. This sounds easier than it really is because most of us are trained to wean from a critical care perspective. We are taught to rapidly wean post-hearts and wean to extubate pneumonia patients.
But SCI patients require a slower, long-term approach. We have to look at these patients from the perspective of how we can support them through the day. Can they manage on a trach collar during the day or will they need rest breaks back on the ventilator? How can we strengthen their respiratory musculature to extend their off vent times? If they can rest comfortably off the vent overnight, will they require an apnea alarm? Is secretion management a problem?”
One way to shift your thinking is to stop thinking of SCI patients as hospitalized patients. Think of them from a home care perspective since this is ultimately where you want them to go. It makes sense to get Mr. White into a wheelchair for a portable vent rather than keep him tethered to a bed and a large monstrosity of a machine.
Weaning is the bread and butter of what we do. SCI patients are just as important as post-hearts and neonates. They have just as many specialized needs. Helping them meet these needs and achieve their goals can be a challenging and rewarding part of our profession.
Charles O’Donnell, MS, RRT, is the director of respiratory care, Boston Medical Center; Margaret Clark is the clinical coordinator for that facility.
