Acute Respiratory and Acid-Base Disorders Flashcards

Vocabulary practice flashcards covering arterial blood gas interpretations, acute respiratory failure, ARDS, mechanical ventilation, trauma, and related pharmacological treatments.

Respiratory Acidosis

An acid-base imbalance characterized by pH $< 7.35$ and $PaCO_2 > 45\,mmHg$, caused by hypoventilation where the lungs retain excess $CO_2$.

DEPRES Mnemonic

A mnemonic representing the causes of respiratory acidosis: Drugs, Edema, Pneumonia (or fluid in the lungs), Respiratory center damaged, Emboli, and Sac elasticity damage (COPD and emphysema).

Respiratory Alkalosis

An acid-base imbalance characterized by pH $> 7.45$ and $PaCO_2 < 35\,mmHg$, caused by hyperventilation where the lungs exhale excessive $CO_2$.

Metabolic Acidosis

An acid-base imbalance characterized by pH $< 7.35$ and $HCO_3^- < 22\,mEq/L$, caused by kidney dysfunction, increased acid production (such as DKA or lactic acidosis), or bicarbonate loss.

Kussmaul Respirations

A deep, rapid breathing pattern used by the respiratory system to compensate for metabolic acidosis by blowing off excess $CO_2$.

Metabolic Alkalosis

An acid-base imbalance characterized by pH $> 7.45$ and $HCO_3^- > 26\,mEq/L$, resulting from conditions causing acid loss (such as severe vomiting or gastric suctioning) or bicarbonate retention.

SvO2 (Mixed Venous)

A measurement of the percentage of oxygen remaining in venous blood after tissues have extracted oxygen, with a normal reference range of $60\%\text{--}80\%$.

V:Q Mismatch

A condition in which ventilation (air flow) and perfusion (blood flow) in the lungs do not line up correctly, leading to hypoxemia or hypercapnia.

Hypercapnic Respiratory Failure

A form of respiratory failure characterized by $CO_2$ retention in the blood, leading to respiratory acidosis, CNS depression, and potential respiratory arrest.

Acute Respiratory Distress Syndrome (ARDS)

A severe form of respiratory failure caused by damage to the alveolar-capillary membrane, making it leaky and allowing fluid into the alveoli, which severely impairs gas exchange.

Prone Positioning

A positional intervention for ARDS patients where they are turned onto their stomach to recruit collapsed alveoli, improve V/Q matching, and reduce cardiac and abdominal compression on posterior lungs.

Positive End-Expiratory Pressure (PEEP)

Ventilator pressure maintained in the lungs at the end of exhalation to prevent alveoli from collapsing and improve oxygenation.

Tidal Volume

The amount of air delivered with each breath by a mechanical ventilator, calculated based on ideal body weight to prevent lung trauma.

End-Tidal Carbon Dioxide (ETCO2)

The level of $CO_2$ measured at the end of an exhaled breath, with a normal range of $35\text{--}45\,mmHg$.

Richmond Agitation Sedation Scale (RASS)

A clinical rating scale ranging from $+4$ (combative, violent, danger) to $-5$ (unarousable to voice or touch) used to measure sedation and agitation levels in ICU patients.

Confusion Assessment Method for the ICU (CAM-ICU)

An assessment instrument used to evaluate ICU patients for delirium based on mental status changes, inattention, level of consciousness, and disorganized thinking.

Cuff-Leak Test

A test performed by deflating an endotracheal tube cuff to listen for air flow around the tube; little or no leak indicates possible airway edema and risk for post-extubation stridor.

Stridor

A high-pitched wheezing sound that indicates an obstructed airway, constituting a medical emergency.

Spontaneous Awakening Trial (SAT)

A protocol involving a temporary pause in sedation to assess whether a patient can wake up, follow commands, and protect their airway.

Spontaneous Breathing Trial (SBT)

A trial in which ventilator support is scaled back to test if a patient can breathe independently prior to extubation.

Carbon Monoxide Poisoning

A state caused by carbon monoxide binding tightly to hemoglobin, displacing oxygen so that oxygen and carbon dioxide can no longer be carried properly.

Pneumothorax

A condition in which air enters the pleural space between the lung and chest wall, causing the lung to partially or completely collapse.

Flail Chest

A traumatic chest wall injury involving broken rib fragments that move paradoxically: inward during inspiration and outward during expiration.

Thoracentesis

A invasive procedure using a needle or catheter to remove air or fluid from the pleural space for diagnostic or therapeutic purposes.

Transudative Pleural Effusion

A fluid collection in the pleural space caused by a pressure imbalance (such as in heart failure) rather than primary tissue inflammation.

Exudative Pleural Effusion

A fluid collection in the pleural space caused by tissue damage or local inflammation (such as pneumonia or cancer).

Empyema

An accumulation of purulent fluid (infected pus) within the pleural space.

Cisatracurium

A neuromuscular blocking drug that paralyzes skeletal muscles to enhance ventilator synchrony without producing sedation or pain relief.

Dexmedetomidine

A sedative used in mechanically ventilated patients that causes minimal respiratory depression, with key adverse effects including bradycardia and hypotension.

Propofol

A rapid-onset, short-acting hypnotic sedative agent used for ventilated patients that lacks analgesic properties and can cause hypotension and respiratory depression.

Mean Arterial Pressure (MAP)

The average pressure in a patient's arteries during one cardiac cycle, calculated as $MAP = \frac{2 \times \text{Diastolic} + \text{Systolic}}{3}$.