Coordinating Care for Critically Ill Patients With Respiratory Dysfunction

Vocabulary practice flashcards generated from Medical-Surgical Nursing (2nd Edition) lecture slides covering pulmonary embolism, V/Q ratio, acute respiratory distress syndrome (ARDS), chest trauma, and chest tube interventions.

Pulmonary Embolism (PE)

A condition occurring when a blood clot, fat, air, or amniotic fluid lodges in a pulmonary artery, obstructing blood flow to the lungs and creating a ventilation-perfusion (V/Q) mismatch.

Fat Embolus Sources

Pulmonary emboli that originate from non-thrombotic sources such as long-bone fractures, osteomyelitis, or liposuction procedures.

Air Embolus Sources

Pulmonary emboli resulting from central venous catheter (CVC) insertion or disconnection (due to negative intrathoracic pressure), cardiopulmonary bypass, or hemodialysis.

Pulsus Paradoxus

A clinical manifestation where systolic blood pressure increases on expiration and drops on inspiration by $10\,\text{mmHg}$ or more.

Heparin

A rapid, short-acting direct-acting parenteral anticoagulant used in acute hospital settings that activates antithrombin III to inhibit thrombin (IIa) and factor Xa, monitored via aPTT, with protamine sulfate as its antidote.

Warfarin

A delayed, long-acting indirect-acting oral anticoagulant that inhibits vitamin K epoxide reductase to decrease synthesis of factors II, VII, IX, and X, monitored via PT/INR, with vitamin K (phytonadione) or FFP as its antidote.

Inferior Vena Cava (IVC) Filter

A vascular device surgically placed in the inferior vena cava to prevent blood clots from traveling from the deep veins of the lower extremities or pelvis into the pulmonary vasculature.

Normal Ventilation-Perfusion (V/Q) Ratio

An indication of how well alveolar ventilation matches pulmonary capillary perfusion, with normal average values of alveolar ventilation ($V \approx 4\,\text{L/min}$) and blood flow ($Q \approx 5\,\text{L/min}$) yielding a ratio of $0.8$.

Low V/Q Ratio (Shunt)

A ventilation-perfusion mismatch condition ($V/Q = 0$) where alveoli are perfused with capillary blood flow but are not ventilated with air.

High V/Q Ratio (Dead Space Ventilation)

A ventilation-perfusion mismatch condition ($V/Q = \infty$) where alveoli are ventilated with air but lack capillary blood perfusion.

Acute Respiratory Distress Syndrome (ARDS)

An acute respiratory failure syndrome defined by onset within $< 7\,\text{days}$, refractory hypoxemia, and bilateral pulmonary infiltrates on chest imaging that rule out cardiac pulmonary edema or volume overload as the primary cause.

Direct Lung Injury Causes of ARDS

Direct insults to the alveoli causing ARDS, including pneumonia, aspiration of gastric contents, mechanical ventilation (barotrauma/volutrauma), lung contusion, toxic inhalation, near-drowning, fat emboli, and reperfusion injury.

Indirect Lung Injury Causes of ARDS

Systemic insults that affect the pulmonary capillaries via blood circulation, including sepsis syndrome (most common cause), non-thoracic trauma, mass blood transfusions, cardiopulmonary bypass, pancreatitis, drug overdose, and burn injuries.

ARDS Severity Classification (PF Ratio)

Classification based on the $PaO_2/FiO_2$ ratio: Mild ($200 - 300\,\text{mmHg}$, $27\%$ mortality), Moderate ($100 - 200\,\text{mmHg}$, $32\%$ mortality), and Severe ($< 100\,\text{mmHg}$, $45\%$ mortality).

Exudative Phase of ARDS

The initial 'wet' phase (days 4 to 7) of ARDS characterized by alveolar epithelial cell injury, increased alveolar-capillary membrane permeability, edema fluid accumulation, and neutrophil-predominant inflammatory recruitment.

Proliferative Phase of ARDS

The second phase (days 7 to 21) of ARDS involving Type II pneumocyte proliferation and differentiation into Type I pneumocytes, edema fluid resorption, and variable development of alveolar and intimal fibrosis.

Fibrotic Phase of ARDS

The late phase (occurring after $21\,\text{days}$) characterized by fibroblast proliferation, loss of alveolar architecture, extensive pulmonary fibrosis, worsening pulmonary hypertension, and long-term ventilator dependency.

Refractory Hypoxemia

A hallmark arterial blood gas abnormality in ARDS where arterial oxygenation ($PaO_2$) continues to decline or remain low despite increases in supplemental delivered oxygen ($FiO_2$).

Flail Chest

A chest trauma condition defined by three or more adjacent ribs fractured in two or more places, creating a free rib segment and resulting in paradoxical chest-wall movement (moving inward on inspiration and outward on expiration).

Tension Pneumothorax

A life-threatening complication of chest trauma where air continuously enters the pleural space, increasing pressure that leads to mediastinal shift, compression of the heart, and tracheal deviation toward the unaffected side.

Hemothorax

An accumulation of blood in the pleural space following chest trauma, leading to loss of negative intrathoracic pressure, restricted lung expansion, and potential hemodynamic compromise.

Pleural Space Respiratory Disorders

Distinguishing conditions affecting the pleural space based on accumulated substance: Pneumothorax (air), Hemothorax (blood), Empyema (pus), and Pleural Effusion (fluid).

Cardiac Tamponade

An emergency condition characterized by fluid build-up within the pericardial sac, resulting in compression of the heart, reduced cardiac filling and output, and requirement for emergent pericardiocentesis/thoracentesis.

Tidaling

The normal, expected fluctuation of water in the water-seal chamber of a chest drainage system that rises with patient inspiration and falls with expiration.

Chest Tube Disconnection Protocol

The immediate nursing action required when a chest tube separates from the drainage system: submerge the distal end of the chest tube in sterile water to re-establish a water seal and prevent atmospheric air entry.

Chest Tube Dislodgement Protocol

The immediate emergency response when a chest tube is accidentally pulled out of the chest wall: apply a sterile occlusive petroleum jelly (Vaseline) dressing over the site and immediately notify the provider.

Chest Drainage System Components

An integrated unit used to evacuate air or fluid from the pleural space, comprising a collection chamber, a water seal chamber, a suction control chamber, and an air leak monitor.