X hits on this document

16 views

0 shares

0 downloads

0 comments

2 / 6

preservation either via modified partial laryngectomy procedures or combined chemo-radiation therapy has become more common (The Department of Veterans Affairs Laryngeal Cancer Study Group, 1991). Secondary laryngectomies are performed for recurrent or persistent disease after prior surgical excisions or radiation therapy or organ preservation with combined radio-chemotherapy. The significance of this is that, in secondary laryngectomy, the tissues being operated on have been violated by prior treatment, disease recurrence, or, in the case of a primary surgery, a more extensive lesion has potentially spread to surrounding tissues. In addition, a laryngectomy is occasionally performed as a last resort for the individual with chronic aspiration and a non-functional larynx either from prior cancer treatment or complications from other benign conditions. Thus, an individual after laryngectomy today presents a more complicated case and frequently requires larger resections and reconstruction procedures. Swallowing difficulties now are recognized as common occurrences after total laryngectomies (Lazarus, 2000). In addition, subtle problems with swallowing now are being found in patients who had undergone previous surgery for less serious disease.

Anatomic Considerations

Total laryngectomy requires separation of the airway from the esophagus. The trachea typically is brought forward below the level of the larynx and is sutured to the base of the neck just above the sternal notch, creating a permanent tracheostoma for breathing. Many times, surgery is extensive and may involve partial to total pharyngectomy, esophagectomy or neck dissection. The significance of added surgery relates to the manner of reconstruction and degree of scarring. Nonetheless, with the separation between trachea and esophagus, aspiration should not occur. However, not only is aspiration possible if complications arise, but dysphagia due to other anatomic/physiologic changes may arise.

In addition to the creation of the tracheostoma, a neopharynx is reconstructed either via primary closure or with reconstructed tissues for larger defects. The most common primary closure methods include the T-shaped, vertical, and horizontal methods, which are all designed with the objective of creating the least amount of tension across suture lines in hopes of preventing complications, such as fistulae, scarring, and strictures.

Specific anatomic deficits occur after removal of the larynx. Along with the cartilages of the larynx, the hyoid bone is removed, which formerly contributed to hyolaryngeal elevation just prior to and during the swallow. The base of tongue forms the upper anastomosis with the neopharynx for reconstruction leading to the pharyngoesophageal sphincter and joined by the closure of the layers of the cricopharyngeus muscles over the sphincter. As such, there may be limits in tongue base retraction either from weakness or decreased range of motion. McConnel (1988) found that higher tongue base to posterior pharyngeal wall pressures are required after laryngectomy to propel a bolus through the pharynx. In addition, the tonicity of the pharyngoesophageal segment, which acts as the upper esophageal sphincter (UES), is affected by the potential driving forces of the tongue base and hyolaryngeal elevation along with the basic tonus of the sphincter itself. As many of these structures have been altered and/or rearranged, relaxation of the sphincter is not as readily accomplished.

Finally, the extent of surgical resection affects anatomic integrity for swallowing. Extensive resections involving base of tongue or pharyngectomy or esophagectomy along with potential cranial nerve deficits may further adversely affect swallowing physiology.

Specific Swallowing Difficulties

Patients typically begin oral feedings, first with liquids, about 5–7 days after surgery in uncomplicated cases. Oral feeding may be delayed 7–14 days after more extensive procedures or after prior radiation, which may negatively affect healing. Barring complications, most patients resume a near-normal diet within a few weeks after beginning oral intake. However,

40

Document info
Document views16
Page views16
Page last viewedMon Dec 05 06:53:30 UTC 2016
Pages6
Paragraphs66
Words3172

Comments