Circulatory System Overview

Perfusion

• Passage of blood or other fluids through blood vessels or tissues.

Blood Flow

• Amount of blood moving through a vessel over time.
• Autoregulation maintains blood flow in tissues.

Blood Pressure

• Force exerted by blood against vessel walls.
• Blood moves due to pressure differences.
• Measured using Korotkoff sounds.

Blood Pressure Categories

• Normal: Less than 120 systolic and less than 80 diastolic mmHg.
• Elevated: 120-129 systolic and less than 80 diastolic mmHg.
• High Blood Pressure (Hypertension) Stage 1: 130-139 systolic or 80-89 diastolic mmHg.
• High Blood Pressure (Hypertension) Stage 2: 140 or higher systolic or 90 or higher diastolic mmHg.
• Hypertensive Crisis: Higher than 180 systolic and/or higher than 120 diastolic mmHg (consult a doctor immediately).

Resistance to Blood Flow

• Factors that inhibit blood flow.
• Viscosity and vessel diameter affect flow.

Pulse Pressure

• Difference between systolic and diastolic pressure.

Mean Arterial Pressure (MAP)

• Average pressure driving blood through vessels.
• Optimal MAP is 70-80 mmHg.

Formula for MAP

• MAP = (systolic BP + 2 * diastolic BP) / 3

Geriatric Cardiovascular and Hematologic Changes

• Myocardial collagen increases, reducing its compliance.
• Other changes affecting cardiac output, peripheral resistance, and heart rate.
• Anemia can occur more frequently in older people.
• Bone marrow function can decrease.
• Iron deficiency anemia can be linked to malnutrition or other factors.

Pulmonary System (Respiratory)

• FiO2: Fraction of inspired oxygen.
• Room air has 21% FiO2.
• Ventilators can provide higher FiO2 levels.
• Pulmonary system brings oxygen into and removes carbon dioxide from the bloodstream.

Upper Respiratory Tract

• Conduction, filtration, humidification, and warming of inhaled air.
• Includes nose, mouth, pharynx, and larynx.

Lower Respiratory Tract

• Conduction and gas exchange.
• Includes trachea, bronchi, lungs, alveoli.

Function of Respiratory System

• Warms and moistens air.
• Protects from particles.
• Voice production.
• Olfaction.
• Acid-base balance.

Arterial Blood Gases (ABGs)

• Assess oxygenation and acid-base imbalances.
• Include respiratory and renal components.

Nasal Cavity

• Humidifies, warms, filters, and conducts air to the respiratory system.

Mucociliary Escalator

• Clears pathogens and particles from the airways.
• Cilia move mucus upwards towards the pharynx.

Sneezing

• Involuntary expulsion of air.
• Removes irritants.

Coughing

• Reflex action to clear airways.
• Caused by diseases, medications, or irritants.

Types of Coughs (Duration and Mucus Production)

• Chronic coughs last longer than 8 weeks.
• Productive coughs produce mucus.
• Non-productive coughs don't produce mucus.

Mechanics of Breathing

• Inspiration (inhaling).
• Expiration (exhaling).
• Ventilation involves moving air into and out of the lungs.
• Respiration is the exchange of gases between the body and environment.

Types of Respiration

• Pulmonary (external respiration) → lungs and blood.
• Systemic (internal respiration) → blood and tissues.

Respiratory Effort

• Characterized by rhythm, quality, rate, and depth of breathing.

Conducting Zone

• Structures from nose to small airways.

Respiratory Zone

• Includes alveoli.
• Site of gas exchange.

Oxygen Saturation

• Measures how much hemoglobin is bound to oxygen.
• Expressed as "O2 Sat."

This quiz covers essential concepts related to perfusion, blood flow, and blood pressure categories. Understand the physiological mechanisms governing blood movement and the significance of blood pressure readings. Test your knowledge on factors affecting resistance to blood flow and pulse pressure.