Ventilation assistance includes a variety of methods designed to help restore or improve breathing function in patients who are unable to adequately breathe on their own. These methods range from at-home oxygen therapy for patients with chronic obstructive pulmonary disease (COPD) to mechanical ventilation for patients with acute respiratory failure. Ventilation assistance therapies usually include the following categories:
Ventilation assistance is used for disease or injury that causes progressive or sudden respiratory failure. It may also be used after surgery until patients recover enough to breathe adequately on their own. Physicians choose the therapy based on the type and stage of the disease process, as well as on the results of blood and pulmonary function tests that indicate the oxygenation status of the patient.
Oxygen therapy
In the case of COPD, oxygen therapy does not treat the disease but can prolong life, increase quality of life, and delay the onset of more serious symptoms. Effective oxygen therapy for any patient should lead to improved or sustained levels of oxygen in arterial blood.
Continuous positive airway pressure (CPAP)
Successful CPAP should result in a reduction in periods of apnea for patients with sleep apnea. Hospitalized patients on CPAP should show improvement in blood gas values and pulse oximetry.
Hyperbaric oxygen therapy
After one or two treatments, scuba divers undergoing emergency treatment in a hyperbaric chamber should exhibit immediate improvement in oxygen levels throughout the body, regardless of blood flow restrictions. Patients receiving oxygen chamber therapy for difficult wounds may receive treatments daily for several weeks before satisfactory results are reached. Patients with carbon monoxide poisoning should show improvement in neurologic function. Results of hyperbaric oxygen therapy depend largely on how quickly the patient was transported to the chamber, as well as on the severity of the initial condition.
Mechanical ventilation
Successful mechanical ventilation should result in a gradual decrease in dependence on the ventilator, with eventual complete restoration of spontaneous respiration. A COPD exacerbation may be successfully treated with mechanical ventilation, and the patient may return to home oxygen therapy. Pediatric patients on long-term mechanical ventilation at home should demonstrate normal growth and development. Some patients in a hospital intensive care unit may be unable to breathe again without the ventilator; if the ventilator is the only thing keeping them alive, families and physicians may have to make hard decisions about continuing life support.
Newborn life support
Ventilation assistance is considered successful when the infant's respiratory rate is reduced by 30–40%, chest x ray and oxygen levels are improved, and the infant is able to breathe spontaneously.
Precautions
Ventilation assistance can be beneficial during acute illness and it may provide a higher quality of life if the patient has end-stage COPD. However, oxygen is not a benign substance, and precautions must be used with any of these therapies.
Preparation
In an acute situation, preparation for any of these treatments includes gathering equipment and educating the patient and/or family about the treatment. At-home oxygen therapy or mechanical ventilation requires education and cooperation with a home health agency and respiratory therapist. Blood and pulmonary function tests are done to assist in individualizing the treatment for the patient.
Aftercare
Blood and pulmonary function tests are performed to verify that the treatment was successful or to monitor and adjust treatments if the therapy is long term. Mechanical ventilation requires frequent oral, nasal, or tracheostomy care for the area surrounding the insertion site of the breathing tube.
Complications
Ventilation assistance can be life saving, but these therapies also create their own set of complications and side effects.
KEY TERMS
Aspiration—Accidental suction of fluids or vomit into the respiratory system.
Endotracheal tube—Tube inserted into the trachea via either the oral or nasal cavity for the purpose of providing a secure airway and delivery of mechanical ventilation.
Hypoventilation—Reduced gas exchange in the lungs resulting in low oxygen levels and high carbon dioxide levels.
Hypoxemia—Deficient oxygen supply in the blood.
Pharmacological paralysis—Paralysis induced by medication to promote optimal mechanical ventilation.
Pneumothorax—Air in the plerual space that can exert pressure on the heart and opposite lung, leading to decreased cardiac and pleural function.
Pulse oximetry—Measure of the percent of hemoglobin saturated with oxygen.
Tracheostomy—Surgically created opening in the trachea for the purpose of providing a secure airway and long term ventilation assistance.
Health care team roles
The nurse and respiratory therapist are responsible for carrying out the physician's orders for any type of ventilation assistance. The nurse monitors the patient's respiratory status and the level of effectiveness of the treatments. The respiratory therapist generally makes any ventilator changes ordered by the physician and sets up equipment required for treatment. Both the nurse and respiratory therapist are responsible for documenting their assessment of the patient's respiratory status. Both are also responsible for teaching the patient and family about the chosen treatment.
The nurse, respiratory therapist, or lab personnel may be responsible for drawing arterial blood gases, but the results are obtained by lab personnel. The nurse may need to inform the physician of the results, as changes in treatment may need to be made. The respiratory therapist often administers pulmonary function tests and reports the results to the physician.
BOOKS
Norris, June, ed. Critical Care Skills: A Nurse's Photo Guide. Springhouse, PA: Springhouse Corporation, 1996.
Porth, C. Pathophysiology: Concepts of Altered Health States. Philadelphia, PA: Lippincott, 1998.
Thelan, Lynne, et al. Critical Care Nursing: Diagnosis and Management. St. Louis, MO: Mosby, 1998.
