Open penetrating external laryngotracheal injury and abdominal trauma by suicide attempt successfully treated with immediate intervention: A case report.

An open penetrating external laryngotracheal injury (PE-LTI) is a rare life-threatening injury requiring immediate intervention. Penetrating injuries may cause tissue loss, which makes wound closure difficult sometimes. Here, we report the case of an open PE-LTI and abdominal trauma by suicide attempt. A 38-year-old Asian man with depression was found in his home after having cut his own neck and abdomen. He was transported to a regional trauma center and immediately intubated. On arrival, his blood pressure was 120/90 mmHg and heart rate was 120 beats/min. Physical examination revealed three cuts each on the neck and abdomen and no dysphonia. The patient's condition was diagnosed as an open PE-LTI, classified as group 5 on the Schaefer classification system and zone II on the Roon and Christensen classification system. He was also evaluated for possible mesenteric injury. We performed an emergency primary laryngotracheal repair and exploratory laparotomy. There was no obvious blood vessel injury, but soft and cartilage tissues were crushed and disconnected completely. On day 8, he underwent wound closure and tracheostomy on the caudal side of the wound. He was successfully weaned from mechanical ventilation on day 9, transferred to the general ward on day 13, decannulated on day 63, and discharged from the hospital thereafter for subacute care. In this case of severe neck injury with complete laryngotracheal separation, tissue losses were relatively minimal. Wound closure presumably occurred early in the absence of blood vessel injury.

Case presentation

A 38-year-old Asian man with depression was found in his home after cutting his own neck and abdomen with a kitchen knife. The emergency response team thought the patient's airway was opened because his trachea was cut completely. He was brought to our regional trauma center and immediately intubated at the emergency department because of concerns of airway obstruction.

On arrival, his blood pressure was 120/90 mmHg, heart rate was 120 beats/min, and body temperature was 36.8 °C. While on controlled mechanical ventilation, he was on synchronized intermittent mandatory ventilation mode and had a tidal volume of 480 mL, respiratory rate of 12 breaths/min, positive end-expiratory pressure of 5 cmH2O, pressure support of 5 cmH2O, and fraction of inspired oxygen of 0.40. Physical examination revealed three cuts on his neck (transverse wound measuring 4 cm, superior to the thyroid cartilage; 2 cm, inferior to the thyroid cartilage; and 2 cm, superior to the left sternoclavicular joint), two cuts on his abdomen (transverse wound of 3 and 2 cm, reaching the peritoneum), and no dysphonia. The head and thoracic computed tomography (CT) images showed no abnormal lesions, although increased CT attenuation indicated laryngotracheal rupture and mesenteric injuries. Flexible nasal endoscopy was not enforced. Arterial blood gas analysis results are shown in Table 1. The electrocardiography, chest radiography, and two-dimensional transthoracic echocardiography results were normal.

Table 1

Laboratory findings on admission.

<Complete blood cell counts>			<Biochemistory>
White blood cells	23,270	/μL	Total protein	6.5	g/dL
Red blood cells	492 × 104	/μL	Alibumin	4.2	g/dL
Hemoglobin	15.4	g/dL	Aspartate transaminase	31	IU/L
Platelet	232 × 103	/μL	Alanine transaminase	40	IU/L
<Coagulation status>			Lactate deydrogenase	415	IU/L
Activated partial thromboplastin time	19.1	sec	Alikaline phosohatase	277	IU/L
Prothrombin time	108	%	Creatinine	0.66	mg/dL
Prothrombin time-international normalized ratio	0.96		Blood urea nitrogen	12.8	mg/dL
Fibrin degradation product	5.9	μg/mL	Total bilirubin	0.5	mg/dL
D-dimer	2.2	μg/mL	Sodium	138	mEq/L
<Arterial blood gas>			Potassium	5.2	mEq/L
FiO2	0.37		Chloride	105	mEq/L
pH	7.325		C-reactive protein	0.23	mg/dL
PaCO2	46.5	mm Hg	Blood sugar	106	mg/dL
PaO2	158	mm Hg	Hemoglobin A 1c	5.4	%
HCO3-	24.2	mmol/L
Base excess	−1.9
Lactate	20	mg/dL

The patient's injury was diagnosed as an open penetrating external laryngotracheal injury (PE-LTI), classified as group 5 on the Schaefer classification system, along with suspected mesenteric injury. He obtained an Injury Severity Scale score of 20, a Revised Trauma Score of 7.840, a survival probability of 0.981, and a Trauma and Injury Severity Score of 0.018. He underwent emergency laryngotracheal repair and exploratory laparotomy. A team of otolaryngologists performed a primary repair of the thyroid cartilage, thyrohyoid bone, and epiglottis. There was no obvious blood vessel injury.

On day 8, he underwent wound closure and tracheostomy on the caudal side of the wound. He was successfully weaned from mechanical ventilation support on day 9, transferred to the general ward on day 13, decannulated on day 63, and discharged from the hospital afterward for subacute care (Fig. 1, Fig. 2).

Fig. 1

(A) Two cuts on the patient's abdomen (transverse wounds measuring 3 cm and 2 cm, respectively). (B) 2-dimensional axial CT showing increased CT value indicative of panniculitis and deep lacerations reaching the peritoneum. (C) Three cuts on the neck (transverse wound measuring 4 cm, superior to the thyroid cartilage; 2 cm, inferior to the thyroid cartilage; and 2 cm, superior to the left sternoclavicular joint). (D) 2-dimensional sagittal CT showing significant subcutaneous emphysema at the level of hyoid bone.

Fig. 2

Discussion

Multiple traumatic injuries, including PE-LTIs, are quite rare and managed only by a team of trauma specialists and otolaryngologists. The initial assessment and management include a trauma survey with primary consideration given to assessing and securing the airway. Several studies show the most common symptoms of neck injury are respiratory distress, subcutaneous emphysema, hoarseness of voice, neck tenderness, stridor, dysphasia, and hemoptysis [[1], [2], [3], [4]]. Patients need to be intubated immediately when signs of airway obstruction occur; however, the decision to intubate at the scene needs careful consideration because of the risk of mucosal soft tissue expansion and airway obstruction resulting from blind intubation. In a systematic review and meta-analysis of 21 studies, more than half of the studies showed pre-hospital intubation was significantly associated with a higher mortality rate [5]. Thus, intubating the patient using bronchofiberscopy, inserting a thinner endotracheal tube or a tracheostomy tube from the laceration remain much safer options. In this case, the patient didn't require intubation at the scene as there was no deviated tissue or blood clots.

A CT angiography is necessary for classifying injuries and choosing treatment options. Although a PE-LTI usually requires surgical intervention for exploration and primary repair, treatment of blunt external or internal LTI depends on the severity of mucosal, cartilage, or bone injury, which require detailed evaluation by a thin-slice scan and angiography.

LTIs are classified according to the severity, site, and tissue injured (cartilage, mucosa, ligaments, nerves, or joints). The American Academy of Otolaryngology-Head and Neck Surgery has accepted the Schaefer classification system as the most useful tool because it allows clinicians to make treatment decisions based on the severity of injury (Table 2) [6,7]. For Group 5 injuries, although tracheostomy and surgical repair are also required, the focus is on securing the airway and performing a primary repair. After that, a complex repair is often performed if the patient's general condition improves. In our case, the patient's injuries were classified as Group 5 and were managed as mentioned above.

Table 2

Schaefer classification system.

Group	Description of injury	Method of evaluation	Management
I	Minor endolaryngeal hematomas or lacerations without detectable fractures	Flexible laryngoscopy	Nonoperative methods (head elevation, voice rest, cool humidification, steroids, antibiotics, and anti-reflux medication)
II	More severe edema, hematoma, minor mucosal disruption without exposed cartilage, or non-displaced fractures	Direct laryngoscopy and esophagoscopy	Tracheostomy
III	Massive edema, large mucosal lacerations, exposed cartilage, displaced fractures or vocal cord immobility	Direct laryngoscopy and esophagoscopy	Tracheostomy or surgical repair
IV	Same as group 3, but more severe with disruption of anterior larynx, unstable fractures, two or more fracture lines, or severe mucosal injuries	Direct laryngoscopy and esophagoscopy	Tracheostomy or surgical repair
V	Complete laryngotracheal separation	Urgent airway evaluation	Primary repair for securing the airway, tracheostomy, and surgical repair

LTIs are also classified using Roon and Christensen's classification system, that divides the neck into three zones when categorizing neck injuries: zone I from the clavicles to the cricoid cartilage, zone II from the cricoid cartilage to the angle of the mandible, and zone III from the angle of the mandible to the base of the skull [8]. Although unstable patients require emergency surgical hemostasis and intervention to secure the airway, mandatory exploration is necessary for stable symptomatic zone II injuries, which was what was done in this case.

In our case, early wound closure was probably because despite complete laryngotracheal separation, the sharp and horizontal lacerations were not accompanied by significant tissue losses. Although jugular vein or vertebral artery injuries are common with neck trauma, the findings from our case indicate that early wound closure may occur in case of an open penetrating external LTI without blood vessel injuries. Thus, there is a need for a new classification system that considers the sharpness of the wound, the degree of tissue loss and disruption, and the nature of the object that caused the injury.

Author contributions

Ryo Kamidani, Hideshi Okada, Rina Kato, Takesumi Nishihori, Bunya Kuze, Takahiro Yoshida, Shozo Yoshida and Shinji Ogura: Treatment of the patient.

Ryo Kamidani: Writing - Original Draft.

Hideshi Okada: Writing - Review & Editing.

All authors read and approved the final manuscript.