Exam 1: Pediatric General Surgery Part 1

Question 1

The ____ and ____ are very compliant in children and are prone to collapse.

Answer 1

• Trachea
• Bronchi

Question 2

In pediatric airways, resistance is inversely related to airway radius to the ________ power.

Answer 2

• 5th

Question 3

Where will there be the greatest resistance in infants?

Answer 3

• Small airways
• Bronchi

This is d/t the relatively small diameter of airway and greater compliance of the trachea and bronchi

Question 4

What is airway obstruction during anesthesia usually caused by?

Answer 4

Loss of muscle tone in pharyngeal and laryngeal structure

Question 5

Where will airway obstruction be most pronounced at?

Answer 5

Hypopharynx at the level of the epiglottis

Question 6

Laryngospasm is a result from an ____ effort, which longitudinally separates the vocal folds from the vestibular folds.

Answer 6

Inspiratory

Question 7

What muscles do not contract during a laryngospasm?

Answer 7

• Instrinsic Muscles
• Extrinsic Muscles

Question 8

Two common causes of laryngospasms

Answer 8

• Stimulation during light anesthesia
• Secretions

Question 9

Name the breathing technique that involves forcefully exhaling air while keeping your airway closed.

Answer 9

The Valsalva Maneuver

Question 10

What is the hallmark sign of a mild laryngospasm?

Answer 10

High-pitch inspiratory stridor d/t cords being partially open

Question 11

What are the treatments for laryngospasm?

Answer 11

• 100 FiO2
• Stop stimulation
• Call for help
• Sniffing position/ Jaw thrust
• IVP of Propofol
• Deepen anesthetic gas
• Positive Pressure (CPAP)
• Sux/Atropine (persistent laryngospasm)

Question 12

Risk factors of intraoperative bronchospasm

Answer 12

• Loss of muscle tone during induction increases WOB
• Asthma
• Smoking
• URI

Question 13

Signs and Symptoms of Intraoperative Bronchospasm

Answer 13

• Polyphonic and prolonged expiratory wheeze
• Increase respiratory effort
• Increase peak airway pressures
• Slow up slope of ETCO2 waveform (shark-fin)
• Increase ETCO2
• Decrease SpO2

Question 14

Describe the capnograph of a bronchospasm.

Answer 14

Slow upslope of ETCO2 waveform (shark-fin)

Question 15

Which induction drugs are excellent bronchodilators?

Answer 15

• Ketamine
• Propofol
• VAAs (not desflurane)

Question 16

Which VA can increase airway resistance in children and should be avoided?

Answer 16

Desflurane

Question 17

List intraoperative treatment for bronchospasm.

Answer 17

• Removing Stimulus
• Deepen anesthesia (IV meds first)
• Inhaled β-agonist
• ↑ FiO2
• Avoid tracheal and vocal cord stimulation
• Decrease PEEP and adjust I:E ratio to minimize air trapping (less I time, more E time)
• IV steroids/ epinephrine

Question 18

How is I:E ratio adjusted to minimize air trapping?

Answer 18

The expiratory time is increased to minimize air trapping.

Question 19

What is the dose of epinephrine to treat intraoperative bronchospasm?

Answer 19

0.05-0.5 mcg/kg every minute

Question 20

What phase of breathing does laryngospasm primarily affect?

What phase of breathing does bronchospasm primarily affect?

Answer 20

• Laryngospasm affects the inspiratory phase
• Bronchospasm affects the expiratory phase

Question 21

What sound is associated with laryngospasm?

What sound is associated with bronchospasm?

Answer 21

• Laryngospasm: Stridor (high-pitch)
• Bronchospasm: Wheeze, Croup

Question 22

Physical presentation of laryngospasm vs bronchospasm.

Answer 22

• Laryngospasm: Retraction of intercostal at the suprasternal notch (tracheal tug)
• Bronchospasm: Increase use of accessory muscles of inspiration (↑ WOB)

Question 23

What are the changes associated with expiration with laryngospasm compared with bronchospasm?

Answer 23

• Laryngospasm: No change in expiration
• Bronchospasm: Prolonged expiration

Question 24

Differentiate the onset of cyanosis of laryngospasm vs bronchospasm.

Answer 24

• Laryngospasm: Cyanosis has fast onset
• Bronchospasm: Cyanosis has slow onset

Question 25

What is Post-Extubation Croup?

Answer 25

* Inflammation/ Edema r/t compression of tracheal mucosa * The reduction in the luminal diameter and increase in airway resistance * Airway resistance (in kids) is inversely related to the radius to the 5th power | can we ask about this? bc Pousillues law says radius to the 4th power?

Question 26

Post-extubation croup can occur in up to ___% of children.

Answer 26

1%

Question 27

List the risk factors of post-extubation croup.

Answer 27

* Larger ETT than airway (no leak > 25 cm H2O) * Change in position during surgery * Repeated intubation attempts/ traumatic intubations * Pediatrics b/w ages 1-4 yrs (subglottic airway narrowest in children) * Surgery length > 1 hour * Previous hx of croup

Question 28

Treatment for Croup in pediatrics

Answer 28

* Nebulized Epinephrine (Racemic Epi) * Steroids (Dexamethasone/Decadron): 0.5 mg/kg

Question 29

Describe how a micro-cuff ETT is used to mitigate the risk of croup in pediatric patients.

Answer 29

* Micro-cuff ETT is high volume, low pressure * Cuff with an elliptical balloon placed more distally * No Murphy's Eye and able to provide uniform surface contact

Question 30

What is the cause of Congenital Diaphragmatic Hernias (CDH)

Answer 30

* Caused by failure of complete closure of pleural and peritoneal canals * Results in herniation of abdominal organs in the thorax

Question 31

How does Congenital Diaphragmatic Hernias (CDH) affect the pulmonary system?

Answer 31

* Inhibits lung growth (division of airways, pulmonary vasculature, decrease bronchi/alveoli) * Decrease SA for gas exchange, leading to increased PVR and pulmonary HTN. * The ipsilateral lung is usually affected

Question 32

Most common type of Congenital Diaphragmatic Hernias (CDH)

Answer 32

* Postlateral Foramen of Bochdalek (90%) * Left side * Associated with the greatest amount of hypoplasia

Question 33

Infants born with Congenital Diaphragmatic Hernias (CDH) are more likely to have what other birth defects?

Answer 33

* Congenital Heart Disease (20-40%) * Chromosomal Abnormalities (5-15%) * GU/GI malformations

Question 34

Diagnosis and Findings of Congenital Diaphragmatic Hernias (CDH)

Answer 34

* Most diagnoses are made prenatally vis US * Findings: Polyhydramnios, intrathoracic gastric bubble, mediastinal shift from herniation site * Antenatal diagnosis via abdominal CXR showing intestinal loops, abdominal organs in thorax, ipsilateral lung compression

Question 35

Signs and Symptoms of Congenital Diaphragmatic Hernias (CDH).

Answer 35

* Respiratory distress * Tachycardia * Tachypnea * Cyanosis (R → L shunting contributes to severe hypoxemia) * Concave abdomen * Barrel Chest * Absent breath sounds on the affected site

Question 36

Congenital Diaphragmatic Hernias (CDH) Treatment

Answer 36

* **Focus on stabilizing and optimizing patient before considering surgery** (used to be a medical emergency) * Improve pulmonary HTN and ↓ PVR * High-frequency oscillatory ventilation (small frequent Vt, limit Peak Pressure, and avoid CPAP). * Vasodilator to ↑ Oxygenation (inhaled NO) * Prostaglandin E1 to maintain PDA and reduce RV afterload * Severe Cases of hypoplasia and pulmonary HTN: ECMO ( Used when PaO2 < 50 mmHg w/ FiO2 of 100%)

Question 37

For patients with Congenital Diaphragmatic Hernias (CDH), what is the major cause of morbidity and mortality undergoing surgical repair w/o ECMO?

Answer 37

* Pulmonary HTN ## Footnote Hyperventialate to decrease PVR

Question 38

Congenital Diaphragmatic Hernias (CDH) Anesthesia Management

Answer 38

* Avoid volutrauma with control ventilation * Avoid increase PVR (hypoxemia, acidosis, hypothermia, hypercarbia) * Decrease PVR (hyperventilation, narcotics to blunt sympathetic discharge) * NGT should be passed before induction to decrease air entering the stomach * Avoid N2O * Paralysis * Fentanyl induction (50 mcg/kg), Roc 1.2 mg/kg or Nimbex 2mg/kg, Sevo as tolerated * Patient will go to the ICU intubated