Exam 2 for 102

The lungs

• principle organs of respiration

• right lung has 3 lobes; left lung has 2

• both lungs have horizontal and oblique fissures

oblique fissure

separates the upper lobes in the lungs from the lower lobes

horizontal fissure

separates the right upper lobe from right middle lobe

• only in right lung!

mediastinum

space in thoracic cavity between the lungs; contains heart, blood vessels, esophagus, trachea, thymus gland, etc.

two parts of the mediastinum

• superior mediastinum (top portion)

• inferior mediastinum (lower portion)

pleural membrane

2 layer membrane the lungs are enveloped in

• visceral pleural and parietal pleura

visceral pleura vs. parietal pleura

visceral: attaches to lungs

parietal: attaches to thoracic cavity

pleural cavity

space between visceral and parietal pleura filled with pleural fluid for lubrication

pressure gradient (when breathing)

during a deep breath, negative intrapleural pressure and negative pressure is created inside the lungs, air flows in to equalize the negative pressure

breathing

process of moving air into (inhaling) and out of (exhaling) the body

respiration

process of gas exchange at a cellular level by which oxygen is made available to cells of body and CO2 and other byproducts are removed (in alveoli)

ventilation

movement of air into and out of the body (via conducting airways)

• not same as breathing

upper airway

includes nose, nasal cavity, mouth, and pharynx

larynx

aka the voice box, is the demarcation (line) between the upper and lower airways

lower airway

trachea, bronchi, bronchioles, alveoli; includes the “respiratory zone”

artificial airways

used to bypass the upper airway to prevent/relieve obstruction for suctioning, prevent aspiration, or provide route for ventilation

mallampati score

amount of throat that shows when mouth is open; used to determine ease of intubation

• 4 classes

intubation

placement of an endotracheal tube; used to maintain airway patency, mechanical ventilation, and/or prevent aspiration

stylet

a thin flexible rod inside endotracheal tube during intubation to provide stability to the tube

laryngoscope

used to visualize larynx and insert endotracheal tube

• 3 parts: light source, handle, and blade

pneumothorax

occurs when air leaks into pleural space; incorrect pressure placement causes lung to collapse and pleural membranes are not longer in contact with each other

pleural effusion

any abnormal accumulation of fluid in pleural cavity; fluid builds up in intrapleural space and restricts expansion of lung tissues (prevents deep breath)

hemothorax

accumulation of blood in the pleural space

venous thromboembolism (VTE)

blood clot in the venous system of the body; often begins as deep vein thrombosis

pulmonary embolism

when a portion of clot breaks off and travels through the bloodstream to lungs; can stop flow of blood and prevent blood from picking up O2 and carrying to the rest of the body

• can also obstruct blood supply to an area of lungs causing necrosis

necrosis

death of tissue

infarction

obstruction of blood flow

pulmonary hypertension

group of progressive diseases characterized by pulmonary vascular resistance, remodeling, and occlusion of pulmonary arterioles

• can lead to right heart failure

chronic obstructive pulmonary disease (COPD

persistant airflow limitation usually progressive and associated with chronic inflammatory response in airway and lungs

coronavirus

positive-stranded RNA virus, 4 geneva: alpha, beta, gamma, delta

asthma

airway inflammation defined by repeated/intermittent occurrence of symptoms (wheezing, dyspnea, chest tightness)

sleep apnea

complete cessation of breathing for 10 seconds or longer

• 5-14 sec = mild

• 15-30 sec = moderate

• 30+ sec = severe

STOP BANG assessment

used for obstructive sleep apnea

• snoring, tired, observed, pressure, body mass index, age, neck size, gender

renal systems

includes kidneys, bladder, ureters, urethra, and urinary meatus

primary function of kidneys

• filtration and excretion of metabolic waste products

• regulation of electrolytes, fluids, and acid-base balance

• stimulation of RBC production

kidneys role in blood pressure

renin-angiotensin-aldosterone system (RAAS) controls reabsorption of water and maintains intravascular volume

renal arteries

only supply of oxygenated blood to kidneys

form of waste product in kidneys

in the form of nonvolatile acids and bicarbonate

nonvolatile acids

aka metabolic/fixed acids

• NOT derived from CO2 and are produced as a result of cellular metabolism

• includes lactic acids, phosphoric acids, sulfuric acids, etc.

amount of bicarbonate reabsorbed

the kidneys filter bicarbonate from blood but 85-90% are reabsorbed!

maintaining bicarb in blood (at normal level)

• if extracellular fluid pH drops = kidneys release hydrogen ions (retain bicarb)

• if extracellular fluid pH rises = kidneys release bicarb (retain hydrogen ions)

hypertension problem (on kidneys)

high pressure directly damages fragile network of blood vessels (glomeruli) within kidneys

• can cause thickening and hardening of renal arterioles

• HTN is 2nd leading cause of CKD

acid-base balance

pH measure of how acidic or alkaline a solution is

acidic = high hydrogen ion concentration

alkaline = high hydroxide ion concentration

alkalosis

high pH level in the body

acidosis

low pH level in the body

alkalemia

high pH level in blood

acidemia

low pH level in blood

normal pH level (for adults)

7.35-7.45

• measured by ABG

pH level of blood is determined by what

assessing the hydrogen ion concentration of the blood, which is regulated through changes in PCO2 and bicarb (HCO3-) concentration

3 primary mechanisms that regulate body’s pH

• chemical buffering mechanisms

• the respiratory system

• the renal system

fatty acids

molecules made up of hydrogen chains with a carboxylic acid group attached at the end

• primary components of lipids (fats)

• active in signaling pathways between cells

• acts as a cellular fuel source

• store energy in adipose tissue as triacylglycerols

• can be saturated or unsaturated

essential fatty acids

required for proper body metabolic function but cannot be made by the body, needs to be ingested

bases

chemical opposite of acids; chemical compound that can accept protons or yields hydroxide ions in solution

hydrolysis

when bases counteract acids by accepting H+ ions

neutralization

reaction between acid and base

• when acid and base combine they form a salt

chemical buffering systems

• carbonic acid buffer systems: regulates pH in intracellular fluid

• phosphate buffer system: regulates pH in extracellular fluid

• protein buffer system: regulates pH in both ICF and ECF

carbonic acid buffer system

maintains balance in blood between bicarb and carbonic acid

• regulated by expiration of CO2 from lungs

phosphate buffer system

maintains homeostasis of fluid inside body’s cells; plays critical role in kidney function; phosphate levels become highly concentrated in tubules

protein buffer system

active primarily inside plasma and cells; accounts for 2/3 of buffering power of blood within cells

• made up of amino acids

hemoglobin

most important protein buffer in the body; buffer for both CO2 and hydrogen ions

• binds with CO2 and promotes release of oxygen from hemoglobin into blood

volatile acids

acids that can be converted into gaseous form, then eliminated by lungs

medulla

directs appropriate response to respiratory musculature because fo changes in arterial PCO2 levels

respiratory system response

• response within 1-3 mins to changing blood PCO2 and provides oxygen as needed

• to maintain proper CO2 concentration in blood, the lungs alter rate and depth of respiration

pH drops = increases rate + depth; increases CO2 release

pH rises = decreases rate + depth; decreases CO2 release

process of kidneys maintaining bicarb concentration

the kidneys maintain bicarb concentration by releasing hydrogen ions or bicarbonate

• extracellular fluid pH drops = kidneys retain bicarb, release hydrogen ions

• extracellular fluid pH rises = kidneys retain hydrogen ions, release bicarb

compensated vs uncompensated

compensated = body is responding to pH level change

uncompensated = body is not responding to pH level change

respiratory acidosis

paCO2 levels rise; pH drops

• kidneys increase reabsorption of HCO3- (elevates pH)

ex: COPD

respiratory alkalosis

paCO2 levels drop; pH rises

• kidneys increase excretion of bicarb and decrease reabsorption of bicarb in the blood

ex: anxiety or sepsis

metabolic acidosis

bicarb levels in blood decrease; pH drops

• pulmonary system increases respiratory rate, decreases paCO2 + elevates pH

metabolic alkalosis

bicarb levels rise; pH levels rise

• pulmonary system decreases respiratory rate, increases paCO2 + hydrogen levels, lower pH

ROME

Respiratory Opposite, Metabolic Equal

• respiratory alkalosis = paCO2 rises, pH drops

• respiratory acidosis = paCO2 drops, pH drises

• metabolic alkalosis = HCO3- rises, pH rises

• metabolic acidosis = HCO3- drops, pH drops

arterial blood gas (ABG)

measures partial pressure of O2, partial pressures of CO2, bicarb levels, and pH of blood

• also used for % of O2 saturation in blood

normal ABG values (important)

pH: 7.35-7.45

paCO2: 35-45 mmHg

HCO3-: 22-24 mmol/L

saturated vs unsaturated fatty acids

saturated: no double bonds

unsaturated: double bonds