Ch.1 Oxygenation Physiology Flashcards
Cellular aerobic metabolism is depended on adequate O2 delivery. What three abilities and mechanisms?
Move O2 (cardiac output), carry O2 (hemoglobin), and ability to extract O2 and deliver it to cells
Aerobic metabolism utilize what three processes?
glycolysis, Krebs cycle, electron transport chain
Anaerobic metabolism utilize what three processes?
glycolysis, pyruvic acid, lactic acid
PO2
partial pressure of O2 in the environment
PAO2
partial pressure of O2 in the alveoli
PaO2
partial pressure of O2 in the blood
what are the four types of hypoxia
hypoxic, hypemic, histotoxic, stagnant
hypoxic hypoxia
deficiency of O2 exchange in the alveoli
hypemic hypoxia
hemorrhage, anemia, and certain drugs causes reduction in blood’s O2 carrying capacity
histotoxic hypoxia
cyanide, ETOH, and carbon monoxide poisoning cause poisoning or metabolic D/O
stagnant hypoxia
caused by reduced cardiac output or pooling of blood like heart failure, PE, or shock states
Hyperlactatemia Classification. 3.
asymptomatic (less than or equal to 2.5 with no symptoms [pH is normal])
symptomatic (lactate > 2.5, with symptoms associated with an anaerobic state [pH is normal])
lactic acidosis (lactate >5 with pH <7.35 and patient symptoms)
alveolar hypoventilation
PaCO2 >45 mmHg
alveolar hyperventilation
PaCO2 <45mmHg
the body’s regulation and maintenance of CO2 could also be summed up as
ventilation
Oxyhemoglobin Dissociation Curve (normal curve)
Hgb has a high affinity but will not remain attached because homeostasis guarantees resupply of O2 due to proper perfusion standards
left shift
high affinity and poor drop off; a left shift is bad for the patient; O2 release, acid, temperature, 2,3-DPG, PaO2 are all low
right shift
decreased affinity and no attachment; O2 unloading, acid, temperature, 2,3-DPG, PaO2 are all raised
a right shift in the Oxyhemoglobin Dissociation Curve depends on these three states
1) perfusion 2) tissue diffusion potential, and 3) overall shock states
Haldane Effect
oxygen concentration determine Hgb’s affinity for CO2
Bohr Effect
Co2 and H+ affect the Hgb’s affinity for O2
ABG trends show high PaO2, what kind of a shift is it and what can we expect of the patient’s condition?
Right shift. This isn’t normal but it’s okay for the patient.
ABG trends show low PaO2, what kind of a shift is it and what can we expect of the patient’s condition?
Left shift. Patient is in a fragile state.
Vital Capacity
Tv+ERV+IRV
Residual Volume
the amount of air left in the respiratory tract following forceful exhalation
Total Lung Capacity (TLC)
VC+RV
dead space
the surfaces of the airway that are not involved in gaseous exchange, ie not alveoli. approx. 2mL/kg
Central Chemoreceptors
located in the medulla/pons
driven by CO2 and H+
Peripheral Chemoreceptors
located in the aortic arch/carotid bodies
driven by O2, CO2, H+
Fick Formula
used to calculate how much O2 a person is using
apneustic respiratory pattern
deep, gasping inspiration with a pause at full inspiration followed by brief, insufficient release
seen in decerebrate posturing
ataxic respiratory pattern
complete irregularity of breathing, with irregular pauses and increasing periods of apnea
seen in damage to medulla secondary to trauma or stroke
Biots
groups of quick, shallow inspirations followed by regular or irregular periods of apnea
damage to the medulla by stroke or trauma, or pressure on the medulla secondary to brainstem herniation
Cheyne-Stokes
progressively deeper and sometimes faster breathing, followed by a gradual decrease that results in temporary apnea
associated with decorticate posturing, Cushings Triad, brainstem herniation
Kussmaul’s respiratory pattern
gradually become deeper, labored, and gasping
high pressure ventilator alarms
kinked line, coughing, secretions or mucus, biting of the tube, reduced lung compliance ie pneumothorax, ARDS, increased airway resistence
low pressure ventilator alarms
chest tube leaks, circuit leaks, airway leaks, hypovolemia, patient disconnection from machine
DOPE
displaced
obstruction
pneumothorax
equipment
