Respiratory Failure

Respiratory Failure Artificial Airways Mechanical Ventilation

Learning Outcomes Describe respiratory failure Describe artificial airways Describe mechanical ventilation Apply nursing management across life span

Respiratory Failure Sudden, life threatening deterioration of the gas exchange function of the lung Patient can not eliminate CO2 from the alveoli CO2 retention results in hypoxemia O2 reaches the alveoli but can not be absorbed or used properly.

Respiratory failure Continued  Lung can move air sufficiently but cannot oxygenate the pulmonary blood properly  Respiratory failure occurs as a result of: mechanical abnormality of the lungs or chest wall defect in the respiratory control center in the brain or Impairment in the function of the respiratory muscles

Acute Respiratory Failure (ARF) Defined as: PaO2 < 50 mm Hg (hypoxemia) PaCO2 > 50 mm Hg (hypercapnia) Arterial pH < 7.35

Chronic Respiratory Failure (CRF)

Defined as:

Deterioration in gas exchange that has occurred over a long period of time after an episode of ARF Absence of acute symptoms and presence of chronic respiratory acidosis Patient develop tolerance to gradual worsening hypoxemia and hypercapnia COPD and neuromuscular diseases

Pathophysiology ARF Ventilation or perfusion mechanism impaired Alveolar hypoventilation Diffusion abnormalities Ventilation-perfusion mismatching shunting

ARF Causes Decreased respiratory drive Dysfunction of the chest wall Dysfunction of the lung parenchyma Post op after major thoracic or abdominal surgery

Decreased Respiratory Drive Severe brain injury Lesions of the brain stem (MS) Use of sedative medications Metabolic disorders (hypothyroidism) Theory: These disorders impair chemoreceptors in the brain to normal respiratory stimulation

Dysfunction of Chest Wall  Any disease of the nerves, spinal cord, muscles or neuromuscular junction involved in respiration seriously affects ventilation e.g. Muscular dystrophy, Polymyositis, Myasthenia gravis, ALS Theory: impulses arising in the respiratory center travel through nerves that extend from the brainstem down the spinal cord to receptors in the muscles of respiration

Dysfunction of Lung Parenchyma Pleural effusion Hemothorax Upper airway obstruction Pneumonia PE

Assessment  Dyspnea  Headache  Restlessness  Confusion  Tachycardia  Cyanosis  Dysrhythmias  Decreased LOC  Alterations in respirations and breath sounds

Nursing Management  Identify and treat the cause of respiratory failure  Administer O2 to maintain PaO2 level above 60 to 70 mm Hg  High fowlers  Encourage deep breathing  Bronchodilators  Prepare patient for mechanical ventilation if supplemental O2 cannot maintain acceptable PaO2 levels

Acute respiratory Distress Syndrome (ARDS) Form of ARF caused by diffuse lung injury leading to extravascular lung fluid Major site of injury is the alveolar capillary membrane Interstitial edema causes compression and obliteration of the terminal airways and leads to reduced lung volume and compliance

ARDS Continued ABG’s identify respiratory acidosis and hypoxemia that does not respond to an increased percentage of O2 Chest x-ray shows interstitial edema Sepsis, fluid overload, shock, trauma, neurological injuries, burns, aspiration amongst some of

Assessment  One of the earliest signs, tachypnea  Dyspnea  Decreased breath sounds  Deteriorating blood gas levels  Hypoxemia despite high concentrations of delivered O2  Decreased pulmonary compliance  Decreased infiltrates

Nursing Management  Administer O2  High Fowlers  Restrict fluid  Respiratory treatments  Diuretics, anticoagulants, corticosteroids  Prepare patient for intubation and mechanical ventilation, using positive end-expiratory pressure (PEEP)

Artificial Airways Adequate ventilation dependent on free movement of air through the upper and lower airways. Many disorders either narrow or block as a result of disease. Foreign bodies or secretions can also impede ventilation

Endotracheal Intubation  Involves passing endotracheal tube through mouth or note into the trachea with aide of a laryngoscope  Once passed a cuff is inflated to prevent air from leaking around the outer part of the tube, to minimize the possibility of aspiration and movement of tube  Provides a patent airway  Method of choice in emergency care

Nursing Management Assess chest expansion for symmetry Auscultate breath sounds Obtain chest x-ray Check cuff pressure every 8-12 hours Monitor for signs of aspiration Secure tube to patients face with tape and mark proximal end for

Nursing Management  Provide for oral care, usually need two professionals as tube needs to be moved from side to side of mouth  Suction prn  Excessive suctioning, speaking can dislodge tube  Maintain cuff inflation  Administer O2 as ordered  Ensure high humidity

Nursing Management Continued Prevent premature removal of tube. Explain to patient and family purpose of tube Last resort is use of soft wrist restraints. Maintain skin integrity

Extubation  Usually respiratory therapist at hospital does this.  Semifowlers position  Cuff is deflated  Monitor for respiratory difficulty e.g. stridor  O2 as prescribed  Inform patient may experience hoarseness or sore throat.

Tracheostomy Surgical incision into the trachea for the purpose of establishing an airway Tracheostomy is the stoma or opening that results from the tracheotomy Can be permanent or temporary

Types (See table 20-1)  Double Lumen  Single Lumen  Cuffed Tube  Cuffless tube  Fenestrated tube  Cuffed fenestrated tube  Metal tracheostomy tube  Talking tracheostomy tube

Double Lumen  Outer cannula: fits into stoma and keeps airway open  Inner cannual: fits into outer cannula and locks into place. Some can e removed and cleaned and reused.  Obturator: stylet with a blunt end used to facilitate direction of tube when inserting. Removed after tube placement

Fenestrated Used to wean patient from a tracheostomy Allows patient to speak Cuffed used with spinal cord paralysis: can facilitate mechanical ventilation and speech.

Nursing Management  Assess respirations for bilateral breath sounds  Monitor ABGs and pulse ox  Encourage deep breathing and coughing  Maintain semi to high fowlers position  Monitor for bleeding  Suction prn  Assess stoma  If tube dislodges, initial nursing action is to grasp the retention sutures to spread the opening

Mechanical Ventilation  Controls patients respirations during surgery or during treatment of severe head injury  Oxygenate the blood when patients ventilator efforts are inadequate  Rest the respiratory muscles  Positive or negative pressure device that maintains ventilation and oxygen delivery for a prolonged period of time

Indications PaO2 < 50 mm Hg with pH < 7.25 Vital capacity < 2 times the tidal volume Negative inspiratory force <25 cm H2O Respiratory rate >35/min

Classification of Ventilators  Negative-pressure Simple and do not require intubation of the airway The iron lung, also known as the Drinker and Shaw tank, was one of the first negative-pressure machines used for long-term ventilation. The machine is a large elongated tank, which encases the patient up to the neck.

Positive Pressure Ventilators  Work by increasing the patient's airway pressure through an endotracheal or tracheostomy tube.  The positive pressure allows air to flow into the airway until the ventilator breath is terminated  Subsequently, the airway pressure drops to zero, and the elastic recoil of the chest wall and lungs push the tidal volume, the breath out through passive exhalation

Types Pressured Cycled  Delivers a flow of air (inspiration) until it reaches a preset pressure and then cycles off  Expiration occurs passively  Intended only for short term  Most common type IPPB machine

Types continued Timed Cycled Pushes air into lungs until a preset time has elapsed Used in newborns or neonatal client

Types Continued Volume-cycled Pushes air into the lungs until a preset volume is delivered A constant tidal volume is delivered regardless of changing compliance of the lungs and chest wall or the airway resistance in the client or ventilator

Types Continued  Noninvasive positive pressure Given via face mask cover nose and mouth, nasal mask CPAP: continuous positive airway pressure BPAP: bi-level positive airway pressure Used for sleep apnea, positive pressure act as a splint keeping the upper airway and trachea open during sleep.

Modes of Ventilation Controlled Set tidal volume at set rate Used for patients who can not initial respiration Least used mode because if patient tries to initiate a breath, the efforts are blocked by the ventilator

Modes continued Assist control (AC) Most commonly used Tidal volume and ventilator rate are preset Ventilator takes over the work of breathing for client Programmed to respond should the patient initiate a breath

Modes Continued Synchronized intermittent mandatory ventilation (SIMV) Similar to AC however allows patient to breath spontaneously at their own rate Can be used as primary or weaning mode. When used in weaning mode, the number of SIMV breaths is gradually decreased and the patient gradually resumes spontaneous breathing

Ventilator controls and settings Tidal volume: volume of air that the client receives with each breath Rate: number of ventilator breaths delivered per minute Fraction of inspired oxygen (FiO2): concentration of oxygen delivered to patient. Determined by ABG

Controls and settings Sighs: volumes of air that are 1.5 to 2 times the set tidal volume, delivered 6 to 10 times per hour PIP: peak airway inspiratory pressure: pressure needed by ventilator to deliver a set tidal volume at a given compliance

Positive End Expiratory Pressure (PEEP) Positive pressure exerted during the expiratory phase of ventilation Improved oxygenation by enhancing gas exchange and preventing adelectasis Need indicates a severe gas exchange disturbance

Nursing management  Assess patient first, ventilator second  VS, lung sounds, respiratory status and breathing pattern  Monitor skin color, lips and nail beds  Monitor chest for bilateral expansion  Assess ventilator settings  Ensure alarms are set  Empty ventilator tubing when moisture collects  T&P client at least every 2 hours