Complete logbooks #2 .docx

Pulmonary Surfactant

Pulmonary Surfactant

A substance surrounding alveoli that reduces surface tension, preventing alveolar collapse by disrupting forces holding water molecules together.

Law of Laplace

States that tension in a spherical or cylindrical structure's wall is proportional to the total of the structure's internal pressure and radius (P x r = T).

Compliance

The ability of the lungs to expand and contract, affected by surfactant levels; decreased compliance leads to increased lung collapsing forces.

Functional Residual Capacity (FRC)

The volume of air left in the lungs after a normal exhale; decreases if collapsing forces in the lungs are greater.

Airway Resistance

Increases due to stress-induced contraction of alveolar radius and lung volume, leading to increased friction and drag, affecting gas exchange.

Work of Breathing (WOB)

Affected by compliance and airway resistance changes, leading to decreased ventilation and altered alveolar gas exchange.

Partial Pressure of Oxygen (PO2)

Decreases due to alveolar collapse, affecting pulmonary circulation by reducing available oxygen for circulation.

Cardiovascular Function

Decreased oxygen intake by red blood cells affects organ oxygenation, compromising bodily functions due to insufficient oxygen supply.

Ventilation Control

Medulla's respiratory center detects changes in CO2 and O2 levels, signaling lungs to adjust breathing to maintain homeostasis.

Alveolar Gas Equation

PAO2 = PIO2 – (PACO2 / RQ); used to calculate alveolar oxygen pressure, with slight discrepancies from direct measurements.

Lung Volumes

Terms include TLC, FRC, RV, FEV1, and FVC, representing different lung capacities and volumes crucial in assessing respiratory function.

FEV1/FVC Ratio

Essential in distinguishing between restrictive and obstructive lung diseases; a high ratio with decreased FVC indicates restrictive diseases, while a low ratio suggests obstructive diseases.

Action Potential Propagation

Describes the process of depolarization, repolarization, and hyperpolarization in an axon, crucial for muscle stimulation and function.

Conduction Velocity

The speed at which an action potential travels down a nerve; measured conduction velocity may vary from typical values due to equipment precision and timing errors.

Conduction Velocity

The time taken for an action potential to travel from one point to another along a nerve.

Equilibrium Potential

The membrane potential at which the electrical driving force on an ion is zero.

Resting Membrane Potential

The electrical potential across a cell membrane when the cell is at rest.

Synaptic Transmission

The process by which neurons communicate with each other at synapses.

Ion Channels

Proteins in the cell membrane that allow ions to pass through.

NMDA Receptors

Receptors that are activated by glutamate and play a role in synaptic plasticity.

GABA Receptors

Receptors that respond to the neurotransmitter gamma-aminobutyric acid.

Autonomic Nervous System

The part of the nervous system responsible for involuntary bodily functions.

Electrocardiogram (ECG)

A test that records the electrical activity of the heart.

Arrhythmias

Abnormal heart rhythms that can be detected by an ECG.

QRS complex

The electrical wave on an electrocardiogram that represents ventricular depolarization.

QRS axis

The overall direction of ventricular depolarization in the heart, determined by analyzing multiple leads.

Systolic blood pressure

The highest arterial pressure during ventricular contraction.

Diastolic blood pressure

The lowest arterial pressure during ventricular relaxation.

Mean arterial pressure (MAP)

The average pressure in the arteries during a cardiac cycle.

Dive response

Physiological changes during breath-holding underwater, including bradycardia and increased peripheral vascular resistance.

Renal clearance

The volume of plasma from which a substance is completely removed by the kidneys in a specified time.

Steady state

When the input and output of a substance in the body are equal over time.

Steady State Concentration

The point at which the rate of excretion matches the rate of infusion, leading to a stable level of a substance in the body.

Inulin Clearance

A measure of the kidney's ability to filter and clear inulin from the blood, used to estimate glomerular filtration rate (GFR).

Creatinine Clearance

A measure of the kidney's ability to filter and clear creatinine from the blood, also used to estimate GFR.

Glomerular Filtration Rate (GFR)

The rate at which blood is filtered by the glomeruli of the kidney, reflecting kidney function.

Elevated Plasma Creatinine Level

Indicates impaired GFR due to reduced filtration of creatinine by the kidneys.

Antidiuretic Hormone (ADH)

Hormone that regulates water permeability in the kidney's collecting ducts, influencing urine concentration and water balance.

Osmoreceptors

Receptors that detect changes in blood osmolarity and help regulate ADH release.

Acid-Base Disorders

Imbalances in the body's pH levels, classified based on changes in bicarbonate and carbon dioxide levels.

Metabolic Acidosis

Condition characterized by low blood pH and bicarbonate levels, often compensated by respiratory mechanisms.

Respiratory Alkalosis

Condition marked by high blood pH and low carbon dioxide levels, typically compensated by metabolic processes.

Renal Compensation

The kidneys utilize CO2 and H2O to synthesize HCO3- and eliminate excess H+ in the urine, causing the pH to rise.

Hyperkalemia

Condition in type 1 diabetes where acidosis leads to excess K+ leaving cells, resulting in elevated blood K+ levels.

Aldosterone

Hormone released by the body to lower blood K+ levels by stimulating K+ excretion and Na+ reabsorption in the kidneys.

Metabolic Acidosis

Acid-base disorder characterized by low HCO3- levels and a decrease in blood pH.

Respiratory Acidosis

Acid-base disorder where the lungs cannot remove enough CO2, leading to decreased pH and increased pCO2 in the blood.