NBCRNA Exam Questions and Answers
Muscle that tenses vocal cords - Answers -Cricothyroid
Muscle that relaxes vocal cords - Answers -Thyroarytenoid
Muscle that abducts vocal cords - Answers -Posterior cricoarytenoid
Muscle that adducts vocal cords - Answers -Lateral cricoarytenoid
Sensory innervation of upper airway - Answers -Trigeminal nerve:
V1 (ophthalmic) - nares + anterior 1/3 septum
V2 (maxillary) - turbinates + septum
V3 (mandibular) - anterior 2/4 tongue
Glossopharyngeal nerve:
Posterior 1/3 tongue/soft palate/oropharynx
Vallecula, anterior epiglottis
Vagus nerve:
SLN (internal branch): posterior epiglottis to vocal cords
RLN: below vocal cords to trachea
Superior laryngeal nerve external branch - Answers -Motor to cricothyroid muscle
Superior laryngeal nerve internal branch - Answers -Sensory posterior epiglottis to vocal
cords
Recurrent laryngeal nerve - Answers -Sensation below vocal cords to trachea
Motor: all intrinsic Laryngeal muscles except cricothyroid
Recurrent laryngeal nerve injury - Answers -Bilateral acute: respiratory distress due to
unopposed action of cricothyroid muscles
Bilateral chronic and unilateral = no respiratory distress
Superior laryngeal nerve injury - Answers -No respiratory distress but possible voice
changes /hoarseness
Glossopharyngeal nerve block location - Answers -Anterior tonsilar pillar
Superior laryngeal nerve block location - Answers -Greater corneu of hyoid bone
,Transtracheal nerve block location - Answers -Cricothyroid membrane
3 paired cartilages of larynx - Answers -Corniculate
Arytenoid
Cuneiform
3 unpaired cartilages of the larynx - Answers -Epiglottis
Thyroid
Cricoid
Adult larynx spinal levels - Answers -C3-C6
Where do vocal cords attach? - Answers -Anteriorly: thyroid cartilage
Posteriorly: arytenoids
Laryngospasm risk factors - Answers -Recent URI
Infants/young children
Asthma
Smoking
ASA 4, prematurity, GERD, OSA
Airway procedures (T&A)
Muscles of inspiration - Answers -Diaphragm, external intercostals
Accessory muscle of inspiration - Answers -Sternocleidomastoid
Scalene
Muscles of active expiration - Answers -Transverse abdominis
Internal obliques
Rectus abdominis
External obliques
(I let the air out of my "tire"s)
V/Q ratio > 1 - Answers -Dead space
V/Q ratio < 1 - Answers -Shunt
Normal minute ventilation - Answers -4 L/min
Normal cardiac output - Answers -5 L/min
Normal V/Q ratio - Answers -0.8
Alveolar gas equation - Answers -PAO2 = FiO2(Pb - PH2O) - PaCO2/RQ
,Pb = 760 at sea level
PH2O = 47
RQ = 0.8
Normal PAO2 at sea level & room air - Answers -~ 105 mmHg
Normal A-a gradient - Answers -5-15 mmHg
Formula for A-a gradient - Answers -(Age/4) + 4
5 causes of hypoxemia - Answers -Normal A-a:
1. Reduced FiO2
2. Hypoventilation
Increased A-a:
3. Diffusion limitation
4. V/Q mismatch
5. Shunt
What cause of hypoxemia can't be fixed with supplemental O2? - Answers -Shunt
Normal IRV - Answers -3000 mL
Normal ERV - Answers -1100 mL
Normal residual volume - Answers -1200 mL
Closing volume - Answers -The volume above residual volume where the small airways
begin to close
The point where dynamic compression of the airways begins
Factors that increase closing volume - Answers -"CLOSE-P"
COPD
LV failure
Obesity
Supine position
Extreme age
Pregnancy
3 tests that measure FRC - Answers -Nitrogen washout
Helium wash in
Body plethysmography
Normal CaO2 - Answers -20 mL O2/dL
, CaO2 equation - Answers -(Hgb x 1.34 x SaO2) + (PaO2 x 0.003)
DO2 equation - Answers -DO2 = CaO2 x CO (L) x 10
Or
DO2 = CaO2 x CO (mL)
Normal DO2 - Answers -1000 mL/min
P50 - Answers -The PaO2 when hgb is 50% saturated
Normal value = 26.5
Factors that cause a left shift in the oxyhemoglobin dissociation curve - Answers -
Increased pH
Decreased temp
Decreased 2,3 DPG
Decreased CO2
Hgb met
Hgb CO
Hgb fetal
Factors that cause a right shift in the oxyhemoglobin dissociation curve - Answers -
Decreased pH
Increased temp
Increased 2,3 DPG
Increased CO2
Maternal hemoglobin
3 ways CO2 is transported in blood - Answers -1. Bicarb (70%)
2. Bound to hemoglobin (23%)
3. Dissolved in plasma (7%)
Pores of kohn - Answers -Allow air movement between alveoli
Type II pneumocytes - Answers -Produce surfactant
Type I pneumocytes - Answers -Structural
Flat squamous cells
Form tight junctions
Type III pneumocytes - Answers -Macrophages
Narrowest part of airway in adults - Answers -Vocal cords
Muscle that tenses vocal cords - Answers -Cricothyroid
Muscle that relaxes vocal cords - Answers -Thyroarytenoid
Muscle that abducts vocal cords - Answers -Posterior cricoarytenoid
Muscle that adducts vocal cords - Answers -Lateral cricoarytenoid
Sensory innervation of upper airway - Answers -Trigeminal nerve:
V1 (ophthalmic) - nares + anterior 1/3 septum
V2 (maxillary) - turbinates + septum
V3 (mandibular) - anterior 2/4 tongue
Glossopharyngeal nerve:
Posterior 1/3 tongue/soft palate/oropharynx
Vallecula, anterior epiglottis
Vagus nerve:
SLN (internal branch): posterior epiglottis to vocal cords
RLN: below vocal cords to trachea
Superior laryngeal nerve external branch - Answers -Motor to cricothyroid muscle
Superior laryngeal nerve internal branch - Answers -Sensory posterior epiglottis to vocal
cords
Recurrent laryngeal nerve - Answers -Sensation below vocal cords to trachea
Motor: all intrinsic Laryngeal muscles except cricothyroid
Recurrent laryngeal nerve injury - Answers -Bilateral acute: respiratory distress due to
unopposed action of cricothyroid muscles
Bilateral chronic and unilateral = no respiratory distress
Superior laryngeal nerve injury - Answers -No respiratory distress but possible voice
changes /hoarseness
Glossopharyngeal nerve block location - Answers -Anterior tonsilar pillar
Superior laryngeal nerve block location - Answers -Greater corneu of hyoid bone
,Transtracheal nerve block location - Answers -Cricothyroid membrane
3 paired cartilages of larynx - Answers -Corniculate
Arytenoid
Cuneiform
3 unpaired cartilages of the larynx - Answers -Epiglottis
Thyroid
Cricoid
Adult larynx spinal levels - Answers -C3-C6
Where do vocal cords attach? - Answers -Anteriorly: thyroid cartilage
Posteriorly: arytenoids
Laryngospasm risk factors - Answers -Recent URI
Infants/young children
Asthma
Smoking
ASA 4, prematurity, GERD, OSA
Airway procedures (T&A)
Muscles of inspiration - Answers -Diaphragm, external intercostals
Accessory muscle of inspiration - Answers -Sternocleidomastoid
Scalene
Muscles of active expiration - Answers -Transverse abdominis
Internal obliques
Rectus abdominis
External obliques
(I let the air out of my "tire"s)
V/Q ratio > 1 - Answers -Dead space
V/Q ratio < 1 - Answers -Shunt
Normal minute ventilation - Answers -4 L/min
Normal cardiac output - Answers -5 L/min
Normal V/Q ratio - Answers -0.8
Alveolar gas equation - Answers -PAO2 = FiO2(Pb - PH2O) - PaCO2/RQ
,Pb = 760 at sea level
PH2O = 47
RQ = 0.8
Normal PAO2 at sea level & room air - Answers -~ 105 mmHg
Normal A-a gradient - Answers -5-15 mmHg
Formula for A-a gradient - Answers -(Age/4) + 4
5 causes of hypoxemia - Answers -Normal A-a:
1. Reduced FiO2
2. Hypoventilation
Increased A-a:
3. Diffusion limitation
4. V/Q mismatch
5. Shunt
What cause of hypoxemia can't be fixed with supplemental O2? - Answers -Shunt
Normal IRV - Answers -3000 mL
Normal ERV - Answers -1100 mL
Normal residual volume - Answers -1200 mL
Closing volume - Answers -The volume above residual volume where the small airways
begin to close
The point where dynamic compression of the airways begins
Factors that increase closing volume - Answers -"CLOSE-P"
COPD
LV failure
Obesity
Supine position
Extreme age
Pregnancy
3 tests that measure FRC - Answers -Nitrogen washout
Helium wash in
Body plethysmography
Normal CaO2 - Answers -20 mL O2/dL
, CaO2 equation - Answers -(Hgb x 1.34 x SaO2) + (PaO2 x 0.003)
DO2 equation - Answers -DO2 = CaO2 x CO (L) x 10
Or
DO2 = CaO2 x CO (mL)
Normal DO2 - Answers -1000 mL/min
P50 - Answers -The PaO2 when hgb is 50% saturated
Normal value = 26.5
Factors that cause a left shift in the oxyhemoglobin dissociation curve - Answers -
Increased pH
Decreased temp
Decreased 2,3 DPG
Decreased CO2
Hgb met
Hgb CO
Hgb fetal
Factors that cause a right shift in the oxyhemoglobin dissociation curve - Answers -
Decreased pH
Increased temp
Increased 2,3 DPG
Increased CO2
Maternal hemoglobin
3 ways CO2 is transported in blood - Answers -1. Bicarb (70%)
2. Bound to hemoglobin (23%)
3. Dissolved in plasma (7%)
Pores of kohn - Answers -Allow air movement between alveoli
Type II pneumocytes - Answers -Produce surfactant
Type I pneumocytes - Answers -Structural
Flat squamous cells
Form tight junctions
Type III pneumocytes - Answers -Macrophages
Narrowest part of airway in adults - Answers -Vocal cords
