Exam 3 Flashcards
Treatment for “sucking chest wound”
Covering the wound with occlusive dressing that is secured on three sides.
Open Pneumothorax
Air enters the pleural space through an opening in the chest wall.
Closed Pneumothorax
No associated external wound
Causes of closed pneumothorax
Rupture of small blebs on visceral pleura, injury to lungs from broken ribs, excessive pressure during ventilation, esophageal tear, laceration or puncture of lungs during subclavian catheter insertion
What do you do if the object that causes an open chest wound is still present?
Do not remove it until a physician is present. Stabilize the impaled object with a bulky dressing.
Tension Pneumothorax
A pneumothorax with rapid accumulation of air in the pleural space that can cause high intrapleural pressures
Results of a tension pneumothorax
Compression of the lung on the affected side and pressure on the heart and great vessels pushing them away from the affected side. As pressures increases, venous return is decreased and cardiac output falls.
Causes of tension pneumothorax
Open or closed pneumothorax; mechanical ventilation, resuscitative measures, chest tubes that are clamped or blocked,
Symptoms of a tension pneumthorax
dyspnea, chest pain radiating to the shoulder, tracheal deviation, decreased or absent breath sounds on the affected side, neck vein distention, and cyanosis.
Hemothorax
Accumulation of blood in the pleural space from an intecostal blood vessel, the internal mammary arter, lung, heart or great vessel.
Clyothorax
presence of lymphatic fluid in the pleural space.
Causes of clyothorax
The thoracic duct is disrupted traumatically or from malignancy and fills the pleural space.
Conservative treatment of clyothorax
chest drainage, bowel rest and paraenteral nutrition. Octreotide, surgery and pleurodesis.
Clinical manifestations of pneumothorax
Small mind tachycardia and dyspnea. If it occurs largely, respiratory distress may be present including shallow, rapid respirations, dyspnea, air hunger, oxygen desat, chest pain, cough with or without hemoptysis, no breath sounds. C-xray shows presence of air or fluid in pleural space and reduction of lung volume.
Management of tension pneumothorax
EMERGENCY!! Insert a arge bore needle into the anterior chest wall at the fourth or fifth intercostal space to release the trapped air. A chest tube is then inserted and connected to water-seal drainage.
Treatment for pneumothorax
Aspirate air/fluid with a large bore needle. (Thoracentesis). Insert a chest tube and attach a water-seal drainage. Repeated spontaneous may be surgically treated with pleurectomy, stapling, and pleurodesis.
Chest tubes used to do what?
Chest Tubes are inserted into the pleural space to remove air and fluid and to allow the lung to reexpand.
Chest Tube Insertion
Positioned seated on the edge of the bed with arms supported on a bedside table or supine with midaxillary area of the affected side exposed.
Chest x-ray is available to confirm the affected side.
Area is cleansed with an antiseptic solution.
Chest wall prepared with a local anesthetic and a small incision is made over a rib. The chest tube is advanced up and over the top of the rib to avoid intercostals nerves and blood vessels. For removal of air, a smaller tube (14F to 22F) is used and is directed anteriorly and superiorly as air rises. For removal of fluid, a larger tube (28F to 40F) is used and directed posteriorly and inferiorly. The chest tube is connected to a pleural drainage system. The incision is closed with sutures and the chest tube is secured. The wound is covered with a dressing. Some physicians prefer to seal the wound with petroleum gauze. Monitor patient for comfort levels, as insertion and presence of chest tube is painful.
Chest tube for air removal
A smaller tube (14F to 22F) is used and is directed anteriorly and superiorly as air rises
Chest tube for fluid removal
A larger tube (28F to 40F) is used and directed posteriorly and inferiorly
Intervention for disconnected chest tube
Reestablishment of the water seal system immediately and attachment of a new drainage system as soon as possible. Some hospitals immerse the tube in sterile water until system can be reestablished.
Chest tube removal procedure
Removed 24 hrs after being on gravity drainage and when the lungs are reexpanded and fluid drainage has ceased. Gather supplies and petroleum jelly dressing. Explain procedure, give pain meds 15 min before, cut suture, pt hold breath or bear down, remove tube, cover with dressing. Do CXR to evaluate for reaccumulation or pneumothorax.
Insufficient CO2 removal results in what
Hypercapnia
hypoxemia
a decrease in arterial O2 (PaO2) and saturation. (SaO2)
Hypercapnia produces what
an increase in arterial CO2. (PaCO2)
When does respiratory failure occur?
When one or both of the gas exchanging functions are inadequate….(transfer of O2 and CO2 between inhaled tidal volumes and circulating blood volume within the pulmonary capillary bed)
Two types of respiratory failure
Hypoxemic or hypercapnic
Primary problem with hypoxemic respiratory failure
inadequate O2 transfer between the alveoli and the pulmonary capillary bed.
Hypoxemic respiratory failure is defined as
PaO2 less than 60 mmHg when the patient is recieving an inspired O2 concentration of >60%.
Hypercapnic respiratory failure is defined as
PaCO2 greater than 48mmHg in combination with acidemia (arterial pH less than 7.35).
Four physiologic mechanisms that may cause hypoxemia and subsequent hypoxemic respiratory failure
- mismatch between ventilation (V) and perfusion (Q), commonly referred to as V/Q mismatch
- shunt
- diffuse limitations
- hypoventilation
In normal lungs, the volume of blood perfusing the lungs each minute is
4 to 5 L/ min
What is the V/Q mismatch?
MIsmatch between ventilation and perfusion. Examples of causes are pneumonia, atelectasis, asthma and pulmonary emboli. Normally VQ is 1:1.
Shunt
when blood exits the heart without having participated in gas exchange.
Anatomic shunt
when blood passes through an anatomic channel in the heart (ventricle septal defect) and bypasses the lungs
Intrapulmonary shunt
Occurs when blood flows through the pulmonary capillaries without participating in gas exchange.
When are intrapulmonary shunts seen>
In conditions in which the alveoli is filled with fluids, like in ARDS, pneumonia, and pulmonary edema.
Treatment for patients with shunts
Usually require mechanical ventilation and a high fraction of inspired O2 (FiO2) to improve gas exchange.
What is diffuse limitation
Occurs when gas exchange across the alveolar-capillary membrane is compromised by a process that thickens, damages, or destroys the membrane.
When does diffuse limitation cause hypoxemia
during exercise more than at rest because the blood moves more rapidly through the lungs which decreases the time for diffusion of O2 across the alveolar capillary membrane.
Classic sign of diffusion limitation
Hypoxemia that is present during exercise but not during rest.
What is alveolar hypoventilation
Generalized decrease in ventilation that results in an increase in PaCO2 and consequent decrease in PaO2.
Hypercapnic respiratory failure results from what
An imbalance between ventilatory supply and ventilatory demand.
When does hypercapnia occur
When ventilatory demand exceeds ventilatory supply and the PaCO2 cannot be sustained within normal limits.
Primary problem with hypercapnic respiratory failure
The inability of the respiratory system to remove sufficient CO2 to maintain a normal PaCO2.
Four groups that can cause a limitation in ventilatory supply
- abnormalities of airways and alveoli
- abnormalities of CNS
- abnormalities of the chest wall
- neuromuscular conditions
Failure of oxygen utilization primarily occurs when?
In septic shock. Adequate O2 may be deliveered to the body tissues, but imparied O2 extraction or diffuse limitation exists at the cellular level. This results in abnormally high amount of O2 returning in venous blood because its not extracted at the tissue level.
Normal PaO2
80 to 100 mmHg
When does hypoxemia occur
the amount of O2 in arterial blood is less than normal values
when does hypoxia occur
when the PaO2 falls sufficiently to cause signs and symptoms of inadequate oxygenation.
Normal IE ratio
Inspiratory to expiratory ratio is normally 1:2, meaning that expiration is twice as long as inspiration.
Oxygen Treatment for hypoxemia due to v/q mismatch
For V/Q mismatch, supplemental oxygen administered 1 to 3 L/min per nasal cannula, or 24% to 32 % by simple face mask or venturi mask should improve the PaO2 and SaO2.
Oxygen Treatment for hypoxemia secondary to intrapulmonary shunt
PPV, which provides O2 therapy and humidification, decreases the work of breathing, and reduces respiratory muscle fatigue. It also assists in opening collapsed airways and decreases shunt.
PPV is provided how?
via endotracheal tube or noninvasively by means of a tight fitting mask.
What levels of PaO2 and SaO2 must the selected O2 delivery system provide?
maintain PaO2 >= to 55 to 60mmHg and SaO2 >= to 90% at the lowest O2 concentration possible.
What will high concentrations of O2 cause?
It will replace nitrogen gas normally present in the alveoli, causing instability and atelectasis.
Oxygen treatment for patients with chronic hypercapnia (patients with COPD)
O2 through a low-flow device such as nasal cannula at 1 to 2 L/min or a venturi mask at 24% to 28%.
Performing augmented coughing, how to?
By placing the palm of your hand or hands on the patient’s abdomen below the xiphoid process. As the patient ends a deep inspiration and begins and expiration, move your hand forcefully downward, increasing abdominal pressure and facilitating the cough.
Huff coughing
A series of coughs performed while saying the word “huff”. It prevents the glottis from closing during the cough.
Staged cough
The patient assumes a sitting position, breaths three or four times in and out through the mouth, and coughs while bending forward and pressing a pillow inward against the diaphragm.
Mini-trach indications
Used to instill sterile normal saline solution to elicit a cough and to perform suctioning.
Mini-trach contraindications
Absent gag reflex, hx of aspiration, and the need for long-term mechanical ventilation.
Contraindications for NIPPV
patients with absent respirations, decreased LOC, high O2 requirements, facial trauma, hemodynamic instability
CPAP
Form of NIPPV in which constant positive pressure is delivered to the airway during inspiration and expiration
BIPAP
Bilevel positive airway pressure, a form of NIPPV in which different positive pressure levels are set for inspiration and expiration
Hemoglobin level that typically ensures adequate oxygen saturation of the hemoglobin
> = 9g/dL (90g/L)
What is ARDS
ARDS is a sudden and progressive form of acute respiratory failure in which the alveolar capillary membrane becomes damaged and more permeable to intravascular fluid.
Causes of ARDS
Sepsis, direct lung injury, Systemic inflammation response syndrome (SIRS), MODS, aspiration of gastric contents, viral or bacterial pneumonia, severe massive trauma, chest truama, embolism, inhalation of toxic substances, near drowning, o2 toxicity, radiation pneumonitis,
Pathophysiology of ARDS
Due to stimulation of the inflammatory and immune systems, which causes an attraction of neutrophils to the pulmonary interstitium. The neutrophils cause a release of mediators that produce changes in the lungs.
What does ascites result from?
(1) Protein shift into lymph space and lymphatic system cannot carry it off and they leak into cavity pulling additional fluid. (2) Hypoalbunemia (3) hyperaldosteronism causing an increase Na+ reabsortion
Treatment for ascites
Sodium restriction, diuretics, and fluid removal. Na+ to 2g/day or 250-500mg/day for severe. K+sparing diuretics in combo with loop diuretics. Paracentesis to remove fluids (temporary fix). Peritoneovenous shunt to reinfuse the ascitic fluid into venous system. TIPS
Complications of peritoneovenous shunts
thrombus formation, infection, fluid overload, DIC, variceal hemorrhage, shunt occlusion.
First step when variceal bleed occurs
Stabilize the patient and manage the airway. IV therapy is administered and may include blood products.
Drug therapy for varicial bleeds
Drug therapy includes Sandostatin, vasopressin, nitroglycerin, and beta blockers.
Prophylactic treatment for non bleeding variceal bleeds
Nonselective beta blockers (propanolol [Inderal])