laryngotracheal separation ( lts ) is the most immediately life - threatening airway injury caused by any of various injuries to the neck including automobile accidents , attempted hanging , and direct blows to the anterior neck [ 1 , 2 ] .
because lts is very so rare , emergency physicians and otolaryngologists have limited experience with it and there is no consensus on its management .
therefore , lts is a diagnostic and therapeutic challenge in airway injuries . a high index of suspicion and immediate reconstruction with restoration of the laryngotracheal framework and mucosal integrity enables patients to recover a patent airway , functional voice , and normal swallowing .
the patient had attempted to hang himself from a height of three stories and was immediately rescued by an eyewitness . on arrival ,
the patient had a hoarse voice but no other symptoms or signs of airway distress .
transverse linear abrasion by a clothes - line was visible on the anterior aspect of the neck at the location of the larynx , and subcutaneous emphysema without any penetrating wounds of the skin was detectible by palpation over an extensive area of the neck and upper chest wall .
cervical and chest x - rays revealed cervical and upper thoracic emphysema but no other abnormality .
multi - detector computed tomography ( mdct ) including multiplanar reconstruction images revealed a complete laryngotracheal separation without fractures of the thyroid and cricoid cartilage .
tracheotomy at the suspected site of separation was performed urgently , after which the patient was transferred to the operating room .
the neck was explored through a transverse incision formed by extending a tracheotomy incision laterally .
the patient had complete transection between the cricoid cartilage and the first tracheal ring , and stretching of the left recurrent laryngeal nerve was observed ( fig .
2 ) . however , the thyroid cartilage , cricoid cartilage , esophagus , and great vessels were intact . before anastomosis ,
release techniques such as suprahyoid release were not used in this patient because of the absence of tracheal cartilage loss .
right side tracheal wall was dissected to avoid damage to the right recurrent laryngeal nerve with great care because stretching injury of left recurrent laryngeal nerve was suspected strongly .
neck extension was eliminated with removal of shoulder roll and the trachea was anastomosed to the cricoid cartilage using interrupted 4 - 0 vicryl sutures .
each suture was passed from extraluminal side to intraluminal side submucosally , with the knot placed extraluminally to minimize the risk of infection , granuloma , and stricture formation . following complete closure ,
the wound was flooded with saline and a valsalva maneuver was performed after the deflation of the cuff of the endotracheal tube to assure an air - tight closure .
the strap muscles were re - approximated in the midline over suction drains , followed by closure of the platysma and skin . to lessen the tension over anastomosis in the postoperative period , the head was kept in flextion position with a nylon suture from the chin to the anterior chest wall .
the endotracheal tube was removed on day 3 in the intensive care unit , and left vocal cord paralysis was observed upon flexible laryngoscopy .
neck computed tomography ( ct ) scan taken at 10 days after the operation demonstrated complete resolution of subcutaneous emphysema and appropriate reconstruction of laryngotrachea ( fig .
the patient was discharged 2 weeks later without a tracheostomy and was lost to follow - up .
airway trauma may be life - threatening , immediately or within several hours after acute injury .
although laryngotracheal injuries represent less than 1% of all traumatic injuries , they account for more than 75% of immediate mortality .
motor vehicle accidents are the most common cause of blunt trauma to the airway , with hanging as a method of attempting suicide increasing in incidence [ 3 , 4 ] .
laryngeal injuries were observed in 35% to 45% of victims of hanging at autopsy . because laryngotracheal separation caused by hanging usually results in early death at the scene , the true incidence is unknown [ 2 , 3 , 5 ] .
typical lts occurs with clothes - line type injuries , as in the present case .
sudden neck extension , fixation of the larynx , and anteroposterior compression of tracheal rings creates shearing forces tearing the cricotracheal membrane .
direct upward pressure by hanging elevates the larynx superiorly and , as a result , larynx , and trachea are separated .
admitted patients with laryngotracheal injury exhibit characteristic signs including hoarseness , dyspnea , subcutaneous crepitus , and skin abrasions over the anterior neck , but their presence vary according to the degree and extent of injury . respiratory distress may be absent , as in the present case , if the separation between the cricoid cartilage and the ends of trachea is not large , allowing adjacent soft tissue around the trachea to form a pseudo - airway and make ventilation possible .
sudden airway obstruction may occur by trial of endotracheal intubation , neck extension or coughing [ 2 , 5 , 7 ] .
fiberoptic laryngoscopy of the upper airway may be helpful for evaluating the site and extent of injury .
however , in the case of highly suspected lts , fiberoptic laryngoscopy should be performed cautiously and with the preparation of a tracheotomy .
irritation by instrumentation may induce effortful cough and disrupt this unstable airway , resulting in abrupt dyspnea .
cephalocaudal separation between cricoid and trachea , abrupt change in position , diameter , and shape of the airway and an extraluminal position of the distal endotracheal tube are the suggestive ct findings of lts .
as shown in this case , sagittal reconstructive image may be useful to evaluate the integrity of laryngotrachea .
tracheotomy is recommended as the method of choice to secure the airway by many authors , because endotracheal intubation may pass into a false track at the site of tracheal separation and obstruct the airway completely [ 2 , 4 , 9 ] .
cricothyroidotomy is not recommended after blunt laryngotracheal injuries , as this may further injure the laryngotrachea .
tracheotomy at the suspected site of separation may be performed rapidly without further tracheal cartilage injury , as in the present case .
after airway is secured , definite surgical repair should be considered as early as possible .
early repair within 48 hours shows improved outcomes with respect to airway and voice and also lower incidence of subglottic stenosis [ 10 , 11 ] . in conclusion ,
a high index of suspicion , adequate imaging , prompt airway establishment , and early surgical repair are the most vital factors in managing the patient with lts ( fig .
 laryngotracheal separation ( lts ) is the most immediately life - threatening airway injury . 
 lts is so rare that very few otolaryngologists have experience with it . 
 lts is one of the diagnostic and therapeutic challenges in airway diseases and its management remains to be established . 
 we experienced a patient with complete lts after attempted hanging . 
 a high index of suspicion , adequate imaging , prompt airway establishment and early surgical repair are the most vital factors in managing a patient with lts . 
INTRODUCTION
CASE REPORT
DISCUSSION