Stoelting Study 11 Tracheal Intubation

Front 1

11. What should the height of the operating room table be to facilitate orotracheal intubation of the trachea via direct laryngoscopy?

Back 1

11. The operating room table should be at a height such that orotracheal intubation via direct laryngoscopy is facilitated. The optimal heighl is one that places the face of the patient at the level of the anesthesiologist's xiphoid process. (lSI)

Front 2

12. What is cricoid pressure? When should it be applied?

Back 2

12. Cricoid pressure, also called Sellick's maneuver, is the application of approximately 5 kg of pressure on the cricoid cartilage by an assistant to the anesthesiologist. Cricoid pressure occludes the esophagus and may prevent the regurgitation of gastric contents during the time between the induction of anesthesia and intubation of the trachea when the airway is not protected. It is important that the assistant not release cricoid pressure until instructed to do so by the anesthesiologist. This should only occur after successful intubation of the trachea has been confirmed by at least two methods. Cricoid pressure does not guarantee that the aspiration of gastric contents will not occur. Indeed, aspiration has occurred despite the correct application of cricoid pressure. Cricoid pressure may also be used to improve the anesthesiologist's view of the larynx during direct laryngoscopy.

Front 3

13. How should the laryngoscope be manipulated during direct laryngoscopy? Describe the procedure for direct laryngoscopy.

Back 3

13. The laryngoscope should be held in the left hand of the anesthesiologist. The blade should be placed on the right side of the open mouth of the patient and moved to midline while sweeping the patient's tongue to the left. The patient's tongue should then lie between the patient's left cheek and the long axis of the blade of the laryngoscope. The laryngoscope blade should then be moved toward the epiglottis until the epiglottis is visualized. Once the epiglottis is visualized the anesthesiologist should properly place the laryngoscope relative to the epiglottis depending on the laryngoscope blade being used, and the laryngoscope and hand t~gether as a unit should lift upward and outward at an approxunate 4)-degree angle in one single motion. The glottic opening should then be visible, and the anesthesiologist should be able to proceed with endotracheal intubation. An attempt should be made by the anesthesiologist to avoid pressure on the patient's teeth, lips, or gums throughout the procedure.

Front 4

14. Where should the curved MacIntosh blade be placed during direct laryngoscopy? What size MacIntosh blade is used for most adult patients?

Back 4

14. During direct laryngoscopy, proper placement of the curved MacIntosh blade is with the tip of the blade in the vallecula. The vallecula is the space between the tongue and epiglottis. Visualization of the glottic opening is achieved by stretching the hypoepiglottic ligament with the tip of the laryngoscope blade. A size 3 MacIntosh blade is used for most adult patients.

Front 5

15. What are some advantages of the MacIntosh blade over other laryngoscope blades for direct laryngoscopy?

Back 5

15. Advantages of the MacIntosh bh.de over oth~r laryngoscope blades for direct · laryngoscopy include less trauma to teeth, the creation of moe room in the mouth to allow for the passage of the endotracheal tube, and less bruising of the epiglottis

Front 6

16. Where should the straight (Jackson-WisconsiJ. or Miller) blade be placed during direct laryngoscopy? What size straight blade is used for most adult patients?

Back 6

16. During direct laryngoscopy proper placement of the straight (Jackson-Wisconsin or Miller) blade is with the tip of the blade beyond the epiglottis between the epiglottis and larynx. When the straight laryngoscope blade is lifted, the epiglottis is one of the structures Ifted by the blade. A size 2 or 3 straight blade is used for most adult patients.

Front 7

17. What are some advantages of the straight blade over other laryngoscope blades for direct laryngoscopy?

Back 7

17. Advantages of the straight blade over other laryngoscope blades for direct laryngoscopy include a straighter line of visualization, better exposure of the glottic opening, easier visualization of an anterior larynx, and easier visualization of the larynx in children.

Front 8

18. What are some characteristics of an endotracheal tube? What size endotracheal tube is typically used in adult patients?

Back 8

18. Endotracheal tubes are characterized by their internal diameter, shape, and whether there is a cuff built into the distal end. They are available in various sizes in increments of 0.5 nun internal diameter. An endotracheal tube with an Internal diameter between 7.0 mm and 8.5 mm is typically used in adult patients. Endotracheal tubes can be shaped differently from the regular slightly curved shape to facilitate their positionIng m a manner that will not interfere with the surgeon's work, as in otolaryngoiogic procedures. Endotracheal tubes are made \ of polyvinyl chloride that is tested to be free of toxins or irritants. In addition, the polyvinyl cWoride molds to the shape of the airway on warming to body temperatu:-e. The tubes are made to be transparent for visualization through the tube, and a radiopaque line enables the clinician to visualize the endotracheal tube and its placement on a radiograph.

Front 9

19. What are some purposes of the cuff at the end of the endotracheal tube? How is the risk of tracheal mucosa ischemia secondary to the cuff pressure minimized?

Back 9

19. The cuff at the end of the endotracheal tube is designed to create a seal in the trachea. The seal facilitates positive pressure of the lungs as well as decreasing cuffs are designed to be low pressureflarge volume. With insufflation of air in cuffs are designed to be low pressure/large volume. With insufflation of air in the endotracheal tJbe cuff the pressure on the tracheal wall is distributed over a larger area, minimizing the risk of excessive pressures on a small portion of the tracheal mucosa. This he:ps minimize the risk of tracheal mucosa ischemia secondary to prolonged endotracheal tube cuff p:essure. Furthermore, the cuff on the endotracheal tube can be inflated until there is just enough air in the cuff to prevent air from leaking around the cuff during positive pressure ventilation of the lungs. The minimum pressure exerted on the tracheal mucosa that still Nevertheless, ciliary denudation has been seen to occur within only 2 hours of placement of an endotracheal tube.

Front 10

23. What is the typical depth of insertion of an encbtracheal tube for midtracheal position in a man? What is the typical depth of insertion of an endotracheal tube for midtracheal position in a woman?

Back 10

23. The typical depth of insertion of an endotracheal tube for the midtracheal position in a man and woman is 23 em and 21 em at the patient's teeth, pectively.

Front 11

24. Why is it important to grade the airway with respect to the degree of visualization of the glottic; opening that was achieved with direct laryngoscopy?

Back 11

This information should be documented because it is valuable information for anesthesiologists who may need to intubate the trachea of the patient at a later date. Documentation should include not only the grade view of the airway but also which laryngoscope blade or blades were used for direct laryngoscopy. Conventionally, the patient's airway has been divided into grades I to IV. A grade I airway is one in which the entire glottic opening is visualized with ease. A grade II air..vay is one in which visualization of just the posterior portion of the glottic opening is possible. A grade III airway is one in which only the epiglottis is able to be visualized. A grade IV airway is one in which the soft palate is the only structure able to be visualized

Front 12

25. With what approximate frequency does a grade ill airway occur? With what apprmumate frequency does a grade IV airway occur?

Back 12

25. A grade ill airway occurs ill 1% to 4% of patients. This grade view historically may require multiple attempts and blades and mayor may not lead to successful intubation of the trachea via direct laryngoscopy. A grade IV airway occurs in ,less than 0.35% of patients and represents a majority of the patients in whom direct laryngoscopy failed to lead to endotracheal intubation.

Front 13

26. If intubation of the trachea via direct laryngoscopy is not possible, how should the anesthesiologist proceed?

Back 13

Typically, the patient will be allowed to awaken after failed inttbation of his or her trachea and the airway is secured lith the patient awake

Front 14

28. What are some conditions in which an awake tracheal intubation may be preferred? What are some advantages to an awake tracheal intubation?

Back 14

28. An awake tracheal intubation may be preferred when attempts at intubation of the trachea by direct laryngoscopy, either past or present, have failed. Advantages to an awake tracheal intubation over asleep intubation are that spontaneous ventilation of the lungs, laryngeal reflexes, and the natural skeletal muscle tone of the airway will all be maintained. The maintained tone allows for better separation of the structures and easier identification of the importall1 landmarks of the aiIway. Finally, the larynx stays in a more posterior position when the patient is awake, making access to it easier

Front 15

29. Describe the procedure for orotracheal intubation in an awake patient.

Back 15

29. Two preparatory things must be fulfilled before orotracheal intubation in an awake patient. First the patient must have an understanding of what is to occur

Front 16

31. What are some possible indications for an awake nasotracheal intubation under fiberoptic guidance?

Back 16

31. Possible indications for an awake nasotracheal intubation under fiberoptic guidance include upper airway obstruction as from tumor, abscess, or prior surgery, a mediastinal mass, subglottic stenosis, congenital airway abnormalities, and an immobile cervical vertebrae.

Front 17

48. What defines difficult mask ventilation?

Back 17

48. Difficult mask ventilation is defined as the inability to maintain arterial oxygenation greater than 90% or the inability of the anesthesiologist alone to reverse the signs of unsuccessful ventilation. These may include lack of chest movement, gastric dilation, cardiopulmonary alterations, and cyanosis.

Front 18

49. What defines difficult tracheal intubation via direct laryngoscopy?

Back 18

49. Difficult tracheal intubation via direct laryngoscopy is defined as the inability of the anesthesiologist to perfonn tracheal intubation via direct laryngoscopy in three attempts, or when successful tracheal intubation requires more than 10 minutes.

Front 19

50. What are some alternatives for the immediate oxygenation of a hypoxic patient in whom attempts at tracheal intubation and mask ventilation have failed?

Back 19

50. Oxygen can be supplied through a catheter or airway placed directly through the cricothyroid membrane. This is usually done under conditions in which attempts at intubation of the trachea and mask ventilation have failed. If the oxygen is supplied by a catheter the subsequent ventilation is termed transtracheal jet ventilation, because it requires a jet ventilator to provide for oxygen flow via the catheter. If this technique is instituted, intermittent disconnection of the catheter from the oxygen source may be necessary to facilitate passive exhalation of the lungs and to avoid hypercarbia. Other risks of small transtracheal catheters for ventilation include displacement of the catheter and subcutaleous emphysema, pneumomedastinum, and barotrauma, making this technique serve only as a short-term solution. An alternative to transtracheal jet ventilation that avoids these risks is a cricothyrotomy. A cricothyrotomy is the creation of a translaryngeal airway through which a small endotracheal tube can be inserted. Its placement requires a scalpel, dilating stylet, and a wire. A cricothyrotomy is not a permanent solution but a temporizing measure until a tracheostomy can )e performed.

Front 20

52. What age of pediatric patient does not require a cuffed endotracheal tube? Why?

Back 20

52. Pediatric patients generally do not require a cuffed endotracheal tube to seal the auway until after the age of 5. In patients younger than 5 years of age, the narrowest diameter of the auway occurs below the vocal cords and an adequate seal can be achieved with an appropriately sized endotracheal tube

Front 21

53. Why is the correct selection of tracheal tube size especially important in pediatric patients? What is a commonly used formula for the selection of endotracheal tube size in pediatric patients?

Back 21

53. The correct selection of tracheal tube size is especially important in pediatric patients because an endotracheal tube too large for the trachea may cause trauma to the larynx or trachea, whereas an endotracheal tube that is too small may not provide an adequate seal. A commonly used formula for selection of endotracheal tube size in pediatric patients is (16 + age)/4.

Front 22

54. How is the correct selection of tracheal tube size confirmed after tracheal intubation of pediatric patients?

Back 22

54. The correct selection of tracheal tube size for pediatric patients is confirmed after its placement by checking the pressure at which a leak will occur around the endotracheal tube when positive pressure is administered to the lungs. A leak: should occur between 15 to 20 cm H2O

Front 23

55. Why is careful depth of insertion of the endotracheal tube especially important in pediatric patients?

Back 23

55. The careful depth of insertion of the endotracheal tube is especially important in pediatric patients because of the small margin of error between appropriate placement, endobronchial intubation, and extubation.

Front 24

56. Anesthesia is not required for orotracheal intubation until what age?

Back 24

56. Anesthesia is not required for orotracheal intubation in neonates younger than 2 weeks of age.

Front 25

57. What type of laryngoscope blade is most frequently used for direct laryngoscopy in the pediatrIc population? Why?

Back 25

57. The laryngoscope blade most frequently used for direct laryngoscopy in the pediatric population is a straight blade. The straight blade typically allows for better visualization of the glottis by directly picking up the epiglottis during direct laryngoscopy. Visualization of the glottic opening is especially easier with a straight laryngoscope blade in patients younger than 3 years of age.

Front 26

58. What equipment and supplies must be available to the anesthesiologist during extubation of the trachea of a patient?

Back 26

58. The equipment and supplies that must be available to the anesthesiologist during extubation of the trachea of a patient are the same as those used during intubation, because the anesthesiologist must always be prepared to re-intubate the trachea should it become necessary.

Front 27

59. Describe the procedure for extubation of the trachea while the patient is still deeply anesthetized. What patients may be candidates for this method of extubation of the trachea? In which patients is this method of extubation of the trachea contraindicated?

Back 27

59. Extubation of the trachea while the patient is still deeply anesthetized requires the patient to not be at risk of aspiration and to be able to adequately ventilate · the lungs spontaneously. The patient must also have an adequate level of anesthesia to prevent laryngospasm or coughing. With these criteria met, the oropharynx should be suctioned, positive pressure to the lungs applied, the pilot balloon deflated, and the endotracheal tube removed from the trachea. Patients who may be candidates for this method of extubation of the trachea are those in whom coughing or bucking on an endotracheal tube may be detrimental to the surgical procedure. Patients in whom intubation of the trachea or ventilation of the lungs with a mask was difficult, or who may have postoperative edema of the airway, are not appropriate candidates for extubation of the trachea while deeply anesthetized.

Front 28

60. Describe the procedure for an awake extubation of the trachea. In which patients is an awake extubation of the trachea indicated?

Back 28

50. Awake extubation of the trachea necessitates both that the patient be able to adequately ventilate the lungs spontaneously and the removal of all anesthetics so that laryngeal reflexes have returned. Often the return of these reflexes is evidenced by the ratient bucking or coughing with the tube in the trachea. When these criteria have been met, the oropharynx should be suctioned, positive pressure to the lungs applied, the pilot balloon deflated, and the endotracheal tube removed from the trachea. Patients who are candidates for an awake extubation of the trachea include any patients in whom aspiration is a risk or patients in whom intubation of the trachea or ventilation of the lungs with a mask was difficult. These patients may also be extubated after a fiberoptic bronchoscope or airway exchange catheter has been placed in the trachea should · tracheal reintubation be necessary

Front 29

61. What is the purpose of suctioning of the oropharynx before the extubation of the trachea?

Back 29

61. Suctioning of the oropharynx before extubation of the trachea minimizes the risk of pharyngeal secretions draining into the trachea after extubation. It also minimizes the risk of stimulation of the vocal cords from secretions causing laryngospasm after extubation.

Front 30

62. What is the purpose of placing positive pressure on the reservoir bag simultaneous to extubation of the trachea?

Back 30

62. Placing positive pressure on the reservoir bag simultaneous to extubation of the trachea results in exhalation after extubation, possibly facilitating the expulsion of secretions after ex.tubation.

Front 31

63. Name three potential hazards of extubation of the trachea.

Back 31

63. Potential hazards of extubation of the trachea include laryngospasm, vomiting, and aspiration

Front 32

64. Name some potential complications of tracheal intubation.

Back 32

64. There are numerous potential complications of tracheal intubation. Complications that may occur during direct laryngoscmy and intubation include dental and oral soft tissue damage, hypertension, tachycardia, myocardial ischemia, cardiac dysrhythmias, and aspiration. Complications that may occur while the tracheal tube is in place include tracheal tube obstruction, endobronchial intubation, esophageal intubation, tracheal tube cuff leak, barotrauma, disconnection from the breathing circuit, tracheal mucosa ischemia, and accidental extubation.

Front 33

65. What is the most frequent complication of direct laryngoscopy?

Back 33

65. The most frequent complication of direct laryngoscopy is dental trauma. Dental trauma occurs m one in every 4500 anesthesias that involve upper airway management. Patients at the greatest risk of dental trauma are patients with poor dentition.

Front 34

66. Should dislodgment of a tooth occur during direct laryngoscopy what measures should be takel by the anesthesiologist?

Back 34

>6. Dislodgment of a tooth during direct laryngoscopy requires that the tooth be recovered. If necessary, chest and abdomen radiographs must be obtained to ensure that the tooth was not aspirated or swallowed.

Front 35

67. What level of anesthesia places the patient most at risk for laryngospasm after extubation of the trachea? How should laryngospasm be treated?

Back 35

67. A light level of anesthesia places the patient most at risk for laryngospasm after extubation of the trachea. Laryngospasm should be treated with the application of positive pressure 100% oxygen via a face rrask and a head-tilt/jaw-lift that or pOSItIve pressure 100% oxygen via a face mask and a head-tilt/jaw-lift that succinylcholine may be necessary.

Front 36

68. Which patient population is most likely to have symptomatic laryngeal or subglottic edema after extubation of the trachea? Why? What can be done to minimize this risk?

Back 36

68. Pediatric patients are most likely to have symptomatic larynge~ or subglottic edema after extubation of the trachea because a small deiftt of swelling may obstruct a significant portion of the airway. The subglottic area in these patients is the narrowest part of the pediatric patient's airway as well. To minimize the risk of laryngeal or subglottic edema after extubation of the trachea, an appropriatel y sized endotracheal tube as evidenced by the leak: pressure should be chosen in pediatric patients

Front 37

69. How should symptomatic laryngeal or subglottic edema after extubation of the trachea be treated?

Back 37

69. Symptomatic laryngeal or subglottic edema after extubation of the trachea should be treated with warmed, humidified oxygen, nebulized racemic epinephnne, and intravenous corticosleroids if necessary. For severe, persistent, or progressive obstruction, re-intubation of the trachea may be necessary.

Front 38

70. What is the most common complication of prolonged intubation of the trachea?

Back 38

70. The most common complication of prolonged intubation of the trachea is tracheal stenosis as an end result of damage to the tracheal mucosa. Tracheal stenosis that results in a tracheal lumen decrease to less than 5 mm causes symptoms for the patient