← Back to Session

Questions Answered: 127

Final Score 99%

126
1

Questions

  • Q1. Correct
  • Q2. Correct
  • Q3. Correct
  • Q4. Correct
  • Q5. Correct
  • Q6. Correct
  • Q7. Correct
  • Q8. Correct
  • Q9. Correct
  • Q10. Correct
  • Q11. Correct
  • Q12. Correct
  • Q13. Correct
  • Q14. X Incorrect
  • Q15. Correct
  • Q16. Correct
  • Q17. Correct
  • Q18. Correct
  • Q19. Correct
  • Q20. Correct
  • Q21. Correct
  • Q22. Correct
  • Q23. Correct
  • Q24. Correct
  • Q25. Correct
  • Q26. Correct
  • Q27. Correct
  • Q28. Correct
  • Q29. Correct
  • Q30. Correct
  • Q31. Correct
  • Q32. Correct
  • Q33. Correct
  • Q34. Correct
  • Q35. Correct
  • Q36. Correct
  • Q37. Correct
  • Q38. Correct
  • Q39. Correct
  • Q40. Correct
  • Q41. Correct
  • Q42. Correct
  • Q43. Correct
  • Q44. Correct
  • Q45. Correct
  • Q46. Correct
  • Q47. Correct
  • Q48. Correct
  • Q49. Correct
  • Q50. Correct
  • Q51. Correct
  • Q52. Correct
  • Q53. Correct
  • Q54. Correct
  • Q55. Correct
  • Q56. Correct
  • Q57. Correct
  • Q58. Correct
  • Q59. Correct
  • Q60. Correct
  • Q61. Correct
  • Q62. Correct
  • Q63. Correct
  • Q64. Correct
  • Q65. Correct
  • Q66. Correct
  • Q67. Correct
  • Q68. Correct
  • Q69. Correct
  • Q70. Correct
  • Q71. Correct
  • Q72. Correct
  • Q73. Correct
  • Q74. Correct
  • Q75. Correct
  • Q76. Correct
  • Q77. Correct
  • Q78. Correct
  • Q79. Correct
  • Q80. Correct
  • Q81. Correct
  • Q82. Correct
  • Q83. Correct
  • Q84. Correct
  • Q85. Correct
  • Q86. Correct
  • Q87. Correct
  • Q88. Correct
  • Q89. Correct
  • Q90. Correct
  • Q91. Correct
  • Q92. Correct
  • Q93. Correct
  • Q94. Correct
  • Q95. Correct
  • Q96. Correct
  • Q97. Correct
  • Q98. Correct
  • Q99. Correct
  • Q100. Correct
  • Q101. Correct
  • Q102. Correct
  • Q103. Correct
  • Q104. Correct
  • Q105. Correct
  • Q106. Correct
  • Q107. Correct
  • Q108. Correct
  • Q109. Correct
  • Q110. Correct
  • Q111. Correct
  • Q112. Correct
  • Q113. Correct
  • Q114. Correct
  • Q115. Correct
  • Q116. Correct
  • Q117. Correct
  • Q118. Correct
  • Q119. Correct
  • Q120. Correct
  • Q121. Correct
  • Q122. Correct
  • Q123. Correct
  • Q124. Correct
  • Q125. Correct
  • Q126. Correct
  • Q127. Correct

Procedural Skills (SLO6)

Question 61 of 127

You have been asked to teach a group of medical students about airway rescue manoeuvres. You are currently discussing cricothyroidotomy. Which of the following is an advantage of needle cricothyroidotomy compared to surgical cricothyroidotomy?

Answer:

  • Disadvantages
    • Only a temporary measure - not a definitive airway
    • Requires high-pressure oxygen source (at 400 kPa)
    • May cause barotrauma, particularly in the presence of expiratory obstruction
    • Particularly ineffective in patients with chest trauma
    • Prone to failure because of kinking of the cannula
    • Unsuitable for maintaining oxygenation during patient transfer
  • Advantages
    • Quick and easy
    • Recommended in failed airway in child where surgical cricothyroidotomy is relatively contraindicated because of risk of damaging cricoid cartilage

Needle Cricothyroidotomy

Needle cricothyroidotomy involves insertion of a wide-bore non-kinking cannula through the cricothyroid membrane to provide oxygen on a short-term basis until a definitive airway can be placed.

Indications

  • Can't intubate, can't oxygenate scenario

Advantages vs disadvantages

  • Disadvantages
    • Only a temporary measure - not a definitive airway
    • Requires high-pressure oxygen source (at 400 kPa)
    • May cause barotrauma, particularly in the presence of expiratory obstruction
    • Particularly ineffective in patients with chest trauma
    • Prone to failure because of kinking of the cannula
    • Unsuitable for maintaining oxygenation during patient transfer
  • Advantages
    • Quick and easy
    • Recommended in failed airway in child where surgical cricothyroidotomy is relatively contraindicated because of risk of damaging cricoid cartilage

Procedure

  • Attach a syringe (preferably 20 mL) to a stiff cannula and needle (minimum 14 gauge in adults)
  • Insert the cannula through the cricothyroid membrane into the airway at an angle of 45 degrees aiming caudally in the midline
  • Confirm cannula position by aspiration of air with the syringe and advance cannula fully over the needle into the trachea
  • Remove the needle, and aspirate air from the cannula to confirm position
  • Hold the cannula in place, attach the ventilation system and commence ventilation
  • One second of oxygen supplied at a pressure of 400 kPa (4 bar) and flow of 15 L/min should be sufficient to inflate adult lungs adequately
  • This is followed by a 4 second pause to enable expiration via the upper airway (expiration does not occur via the cannula)
  • In children the intial flow rate should equal the child's age in years, and this is increased in 1 L/min increments until one second of oxygen flow causes the chest to rise
  • Look carefully for adequate exhalation through the upper airway (chest falls adequately with each expiration)
  • The patient can be adequately oxygenated for 30 - 45 mins using this technique (because of inadequate exhalation, build up of CO2 occurs)
  • If ventilation fails, or complications occur, proceed immediately to surgical cricothyroidotomy

Complications

  • Barotrauma from high pressure ventilation including pulmonary rupture with tension pneumothorax
  • Inadequate ventilation due to kinking or obstruction of the cannula
  • Aspiration of blood
  • Oesophageal laceration
  • Haematoma
  • Perforation of posterior tracheal wall
  • Subcutaneous and/or mediastinal emphysema
  • Thyroid perforation

Clinical anatomy

Site of Airway Procedures. (Image by PhilippN [CC-BY-SA-3.0 , via Wikimedia Commons)

Report A Problem

Is there something wrong with this question? Let us know and we’ll fix it as soon as possible.

Loading Form...

Close
  • Biochemistry
  • Blood Gases
  • Haematology
Biochemistry Normal Value
Sodium 135 – 145 mmol/l
Potassium 3.0 – 4.5 mmol/l
Urea 2.5 – 7.5 mmol/l
Glucose 3.5 – 5.0 mmol/l
Creatinine 35 – 135 μmol/l
Alanine Aminotransferase (ALT) 5 – 35 U/l
Gamma-glutamyl Transferase (GGT) < 65 U/l
Alkaline Phosphatase (ALP) 30 – 135 U/l
Aspartate Aminotransferase (AST) < 40 U/l
Total Protein 60 – 80 g/l
Albumin 35 – 50 g/l
Globulin 2.4 – 3.5 g/dl
Amylase < 70 U/l
Total Bilirubin 3 – 17 μmol/l
Calcium 2.1 – 2.5 mmol/l
Chloride 95 – 105 mmol/l
Phosphate 0.8 – 1.4 mmol/l
Haematology Normal Value
Haemoglobin 11.5 – 16.6 g/dl
White Blood Cells 4.0 – 11.0 x 109/l
Platelets 150 – 450 x 109/l
MCV 80 – 96 fl
MCHC 32 – 36 g/dl
Neutrophils 2.0 – 7.5 x 109/l
Lymphocytes 1.5 – 4.0 x 109/l
Monocytes 0.3 – 1.0 x 109/l
Eosinophils 0.1 – 0.5 x 109/l
Basophils < 0.2 x 109/l
Reticulocytes < 2%
Haematocrit 0.35 – 0.49
Red Cell Distribution Width 11 – 15%
Blood Gases Normal Value
pH 7.35 – 7.45
pO2 11 – 14 kPa
pCO2 4.5 – 6.0 kPa
Base Excess -2 – +2 mmol/l
Bicarbonate 24 – 30 mmol/l
Lactate < 2 mmol/l

Join our Newsletter

Stay updated with free revision resources and exclusive discounts

©2017 - 2024 MRCEM Success