Med Surg II Exam 2

Gas Exchange

The process of oxygen and carbon dioxide exchange between the lungs and bloodstream.

Ventilatory Support

Assistance provided to patients who are unable to breathe adequately on their own.

Pneumothorax

A condition where air enters the pleural space, causing lung collapse.

Pulmonary Embolism (PE)

A blockage in a pulmonary artery usually caused by blood clots that travel to the lungs.

Obstructive Shock

A type of shock caused by a physical obstruction of blood flow.

Intracranial Pressure (ICP)

The pressure inside the skull, which can affect brain function; normal range is 10-15 mm Hg.

Ischemic Stroke

A type of stroke caused by a blockage in a blood vessel supplying blood to the brain.

Hemorrhagic Stroke

A type of stroke caused by bleeding in or around the brain.

Traumatic Brain Injury (TBI)

An injury to the brain caused by an external force, such as a blow to the head.

Infective Endocarditis

An infection of the inner lining of the heart, often caused by bacteria.

Aortic Aneurysm

An abnormal bulge in the wall of the aorta that can rupture and cause life-threatening bleeding.

Aortic Dissection

A serious condition in which the inner layer of the aorta tears, allowing blood to flow between the layers.

Cardiogenic Shock

A condition where the heart suddenly can't pump enough blood to meet the body's needs.

Preload

The amount of blood in the heart right before contraction; influences ventricular filling pressure.

Afterload

The resistance the ventricle must overcome to eject blood during contraction.

Contractility

The strength of the heart's contraction; influenced by various factors including heart muscle condition.

Heart Rate (HR)

The number of heartbeats per minute, a key determinant of cardiac output.

Mean Arterial Pressure (MAP)

The average pressure in a patient's arteries during one cardiac cycle; normal is > 65 mm Hg.

Central Venous Pressure (CVP)

The pressure in the thoracic vena cava near the right atrium; normal range is 2-6 mm Hg.

Pulmonary Artery Pressure (PAP)

The pressure in the pulmonary artery; normal range is 15-25 / 8-15 mm Hg.

Pulmonary Capillary Wedge Pressure (PAWP)

A measure of left atrial pressure; normal range is 6-12 mm Hg.

Stroke Volume (SV)

The amount of blood pumped by the heart with each beat; normal range is 60-100 mL/beat.

Cardiac Index (CI)

A measure of the cardiac output of a patient per square meter of body surface area; normal range is 2.2-4.0 L/min/m².

Ejection Fraction (EF)

The percentage of blood that is pumped out of the heart's chambers with each contraction; normal range is 50-75%.

Lactate

A marker of anaerobic metabolism; normal range is 0.5-2.0 mmol/L.

Mixed Venous Oxygen Saturation (SvO₂)

The amount of oxygen remaining in the blood after it has circulated through the body; normal range is 60-80%.

Norepinephrine

A medication that increases blood pressure by causing vasoconstriction and increasing afterload.

Dobutamine

A medication that increases heart contractility and cardiac output.

Milrinone

A medication that increases contractility and decreases afterload, often used in heart failure.

Furosemide

A diuretic that decreases preload by promoting fluid loss.

Nitroglycerin

A medication that decreases preload and can also reduce afterload, used to relieve angina.

Diltiazem

A calcium channel blocker that decreases heart rate (HR) and contractility, slows AV conduction, and can reduce cardiac output (CO) and blood pressure (BP) in a failing heart.

Metoprolol

A beta-1 blocker that decreases heart rate and contractility, reducing oxygen demand and shear force, but can cause bradycardia and hypotension; should be avoided in cardiogenic shock.

PEEP

Positive end-expiratory pressure that increases intrathoracic pressure, which can compress the vena cava, leading to decreased venous return, cardiac output, and blood pressure.

Needle decompression

A procedure to restore preload by releasing trapped air in the mediastinum, allowing venous return to be restored and increasing cardiac output.

IABP

Intra-aortic balloon pump that decreases afterload and increases coronary flow by inflating during diastole and deflating before systole.

Fluid bolus

An intervention to increase preload, leading to increased stroke volume if the heart can respond, but can worsen pulmonary edema in failing left or right ventricles.

Shock stages

Different stages of shock characterized by changes in blood pressure, heart rate, and signs of tissue perfusion.

Compensatory shock

A stage where blood pressure is 10-15 mmHg below baseline, with activation of the sympathetic nervous system and neurohormonal responses, leading to signs like anxiety and tachycardia.

Progressive shock

A stage where mean arterial pressure (MAP) is sustained more than 20 mmHg below baseline, indicating failing compensation and tissue hypoxia.

Refractory shock

An irreversible stage of shock characterized by rapid loss of consciousness, non-palpable pulse, and signs of severe tissue hypoxia.

Respiratory distress

Abnormal respiratory rate or depth indicating difficulty in breathing.

Respiratory failure

A condition where the lungs fail to ventilate or oxygenate adequately.

Respiratory arrest

The cessation of breathing.

Ventilation

The movement of air in and out of the alveoli, essential for clearing carbon dioxide.

Diffusion/transport

The process of oxygen crossing the alveolar-capillary membrane and binding to hemoglobin.

Perfusion

The blood flow past the alveoli, necessary for gas exchange.

V/Q mismatch

A condition where ventilation does not match perfusion, leading to inadequate gas exchange.

Hypoxia

A deficiency in the amount of oxygen reaching the tissues, with early signs including restlessness and tachycardia, and late signs including cyanosis and bradycardia.

Acid-base balance

The regulation of pH in the body, primarily managed by the lungs and kidneys.

ABG normal ranges

Normal arterial blood gas values: pH 7.35-7.45, PaCO₂ 35-45 mm Hg, HCO₃⁻ 22-26 mEq/L, PaO₂ 80-100 mm Hg, SaO₂ 95-100%.

Respiratory acidosis

A condition caused by hypoventilation leading to CO₂ retention, resulting in decreased pH and potential complications like dysrhythmias.

ARDS

Acute Respiratory Distress Syndrome, characterized by extreme hypoxia, bilateral infiltrates, and decreased pulmonary compliance, occurring without heart failure.

P/F ratio

The ratio of arterial oxygen partial pressure to fractional inspired oxygen, used to diagnose and grade ARDS; lower ratios indicate more severe ARDS.

What is tachypnea?

Tachypnea is an abnormally rapid breathing rate, often indicating respiratory distress.

What is hypotension?

Hypotension is a condition where blood pressure is lower than normal, which can lead to inadequate blood flow to organs.

What is bradycardia?

Bradycardia is a slower than normal heart rate, typically defined as fewer than 60 beats per minute.

What does PEEP stand for?

PEEP stands for Positive End-Expiratory Pressure, a mode of mechanical ventilation that keeps alveoli open at the end of expiration.

What is the purpose of prone positioning?

Prone positioning helps recruit collapsed alveoli and improves ventilation-perfusion (V/Q) ratio by taking pressure off the dorsal lung.

What are the benefits of PEEP?

PEEP improves alveolar recruitment, compliance, functional residual capacity, and oxygenation in the lungs.

What are the risks of PEEP?

Risks of PEEP include reduced venous return, hypotension, barotrauma, and air trapping.

What is the function of a non-rebreather mask?

A non-rebreather mask delivers high concentrations of oxygen and is used as a first rescue device for patients in respiratory distress.

What is the flow rate for a nasal cannula?

The flow rate for a nasal cannula is typically between 1 to 6 liters per minute, providing 24% to 44% oxygen.

What is the purpose of a Venturi mask?

A Venturi mask provides precise oxygen delivery by using color-coded adapters to control the flow rate and FiO₂.

What is the difference between NPPV and IPPV?

NPPV (Noninvasive Positive Pressure Ventilation) uses a mask and requires the patient to breathe spontaneously, while IPPV (Invasive Positive Pressure Ventilation) uses a tube and delivers set breaths.

What are the indications for intubation?

Indications for intubation include persistent hypoxemia, alveolar hypoventilation, respiratory acidosis, and a Glasgow Coma Scale (GCS) score of 8 or less.

What is FiO₂?

FiO₂ stands for Fraction of Inspired Oxygen, which is the percentage of oxygen in the air mixture that a patient inhales.

What does the I:E ratio represent?

The I:E ratio represents the ratio of the duration of inspiration to expiration during mechanical ventilation, with a normal ratio being 1:2 to 1:3.

What is tidal volume?

Tidal volume is the amount of air delivered to the lungs with each breath, typically measured in milliliters.

What does PIP stand for?

PIP stands for Peak Inspiratory Pressure, which is the maximum pressure required to deliver a set tidal volume to the lungs.

What are common causes of high-pressure alarms on a ventilator?

Common causes include secretions, biting the tube, kinks in the tubing, agitation, coughing, or bronchospasm.

What are common causes of low-pressure alarms on a ventilator?

Common causes include circuit disconnects, ETT (endotracheal tube) disconnects, cuff leaks, or vent circuit leaks.

What is the purpose of the ventilator bundle?

The ventilator bundle aims to prevent ventilator-associated pneumonia (VAP) and includes measures like head-of-bed elevation and oral care.

What is barotrauma?

Barotrauma is lung injury caused by excessive pressure, which may result in pneumothorax or tension pneumothorax.

What is the significance of cuff pressure in tracheostomy?

Cuff pressure in tracheostomy should be maintained between 15-22 mm Hg to ensure airway patency and prevent aspiration.

What is the role of sedation in ventilated patients?

Sedation is used to ensure patient comfort, prevent agitation, and facilitate compliance with mechanical ventilation.

What is the Glasgow Coma Scale (GCS)?

The Glasgow Coma Scale is a neurological scale used to assess a patient's level of consciousness, with scores ranging from 3 to 15.

What is the primary complication associated with excessive PEEP?

The primary complication associated with excessive PEEP is hypotension due to decreased venous return.

What is the purpose of oral care in ventilated patients?

Oral care in ventilated patients is crucial for preventing ventilator-associated pneumonia (VAP) and maintaining oral hygiene.

What is the significance of monitoring ABGs?

Monitoring arterial blood gases (ABGs) helps assess the effectiveness of ventilation and oxygenation in patients.

What is a primary spontaneous pneumothorax?

A pneumothorax that occurs without any underlying lung disease, often seen in tall, thin young adults without trauma.

What is a secondary spontaneous pneumothorax?

A pneumothorax that occurs due to underlying lung diseases such as COPD, asthma, cystic fibrosis, or interstitial lung disease.

What causes a traumatic pneumothorax?

It is caused by blunt or penetrating chest trauma, rib fractures, or medical procedures like central line placement or thoracentesis.

What is a tension pneumothorax?

A medical emergency where air enters the pleural space but cannot escape, leading to increased intrathoracic pressure and potentially obstructive shock.

What are the symptoms of a tension pneumothorax?

Symptoms include sudden chest pain, dyspnea, tachypnea, tachycardia, decreased SpO₂, diminished breath sounds on the affected side, and tracheal deviation.

What is the diagnostic method for pneumothorax?

Chest X-ray (CXR) shows a visible pleural line and absent lung markings; ultrasound can show no lung sliding; CT is the most sensitive.

What is the treatment for a tension pneumothorax?

Immediate needle decompression followed by chest tube insertion.

What is a pulmonary embolism?

A blockage in the pulmonary artery usually caused by a clot that has traveled from the deep veins of the legs (DVT).

What is Virchow's triad?

A set of three factors that contribute to thrombus formation: venous stasis, hypercoagulability, and vessel injury.

What are the common symptoms of a pulmonary embolism?

Symptoms include sudden dyspnea, pleuritic chest pain, tachypnea, tachycardia, anxiety, hypoxemia, and occasionally hemoptysis.

What is the gold standard diagnostic test for pulmonary embolism?

CT pulmonary angiography is the gold standard for diagnosing pulmonary embolism.

What is the role of D-dimer in diagnosing pulmonary embolism?

D-dimer is sensitive but not specific; it can be elevated in various conditions, including sepsis and trauma.

What is the purpose of heparin in treating pulmonary embolism?

Heparin prevents the clot from growing and new clots from forming but does not dissolve existing clots.

What is the function of alteplase in pulmonary embolism treatment?

Alteplase is a fibrinolytic agent that dissolves clots in cases of massive pulmonary embolism.

What is obstructive shock?

A type of shock caused by an obstruction that prevents adequate blood flow, leading to decreased perfusion and hypoxia.

What are the tell-tale signs of tension pneumothorax?

Absent breath sounds on one side, tracheal deviation, and hyperresonance on percussion.

What is the significance of Beck's triad?

Beck's triad consists of JVD, hypotension, and muffled heart tones, indicating cardiac tamponade.

What is intracranial regulation?

The brain's ability to maintain normal intracranial pressure (ICP) and ensure adequate blood perfusion and function.

What is the normal range for intracranial pressure (ICP)?

Normal ICP is 10-15 mm Hg; sustained ICP greater than 20 mm Hg is detrimental.

What is the formula for cerebral perfusion pressure (CPP)?

CPP = Mean Arterial Pressure (MAP) - ICP, with a normal range of 70-100 mm Hg.