Anatomy relevant to airway procedures and ICCs

Tracheostomy - percutaneous insertion of tube into trachea to facilitate ventilation. Ideally inserted between 2nd and 3rd tracheal rings.

The trachea

• Fibroelastic tube, 10-15cm
• Origin: from larynx at c6 / cricoid cartilage
• Anteriorly has 16-20 c-shaped cartilagenous rings
• Posteriorly has trachealis muscle
• Terminates at carina at T4/5; divides into 2 main bronchi

Relations of trachea in the neck

• Anterior: Skin \(\to\) fat \(\to\) superficial fascia \(\to\) deep fascia. Thyroid isthmus overlies rings 2-4; superior thyroid arteries, superior, middle, and inferior thyroid veins, anterior jugular vein.
• Anterolateral: Sternohyoid and sternothyroid muscles
• Immediately lateral: recurrent laryngeal nerve (innervates all muscles of larynx except cricothyroid m), superior laryngeal nerve, thyroid lobes
• Posterolateral: Carotid sheath (IJV, carotid a, CN X)
• Posterior: Oesophagus, vertebral bodies

ICC - percutaneous insertion of tube into pleural space to drain air or fluid

Inserted either

1. Anteriorly, in 2nd ICS in mid clavicular line (rare), or
2. In the triangle of safety:

Neurovascular bundle runs on inferior edge of rib in groove (intercostal a., v., n.); so ICC must be inserted just atop rib.

Layers encountered

1. Skin
2. Subcutis/fat
3. Fascia
4. External \(\to\) internal \(\to\) innermost intercostal mm
5. Fascia
6. Parietal pleura
7. Pleural space

Relations:

For a left ICC

• Deep: lung, pericardium, heart
• Inferior: Diaphragm, spleen, splenic flexure

For a right ICC

• Deep: lung
• Inferior: Diaphragm, liver, hepatic flexure

For an anterior ICC

• Deep: Lung, heart
• Superior: subclavian vessels
• Medial: internal mammary artery