4 | Discussion
Deep neck spaces are multiple spaces including the parapharyngeal space,
the posterior pharyngeal space, the sublingual space and the lower jaw
space(4). DNSI is often secondary to infection of tonsil, teeth, upper
respiratory tract or deep neck surgery(5). If the infection can not be
controlled in time, it can spread to each other through the deep neck
spaces, even up to the skull base and down to the mediastinum. It can
also cause other parts of the abscess, and even systemic symptoms. DNSI
also lead to upper respiratory tract obstruction, and eventually cause
serious consequences and even death.
Our study showed that the most frequently involved deep neck spaces were
parapharyngeal space (27 cases) and submandibular space (11 cases),
which were consistent with the results of Huang et al (6). Some
studies also supported that parapharyngeal space and submandibular space
were the most frequently involved deep neck spaces(5,7,8).
In case 1, the patient was diagnosed as necrotizing myofascitis of the
neck. In general, there was not much pus during the operation. Once the
drainage cavity was exposed, the pus would increase sharply, even up to
150 ml of drainage per day. In view of this situation, we used the
pyogenic cavity aerobic therapy, which was to pass the oxygen tube to
the operation cavity, and the oxygen flow is initially adjusted to
3L/min. After the first use, the pus exudation was reduced to about
10-15 ml the next day, and then according to the amount of exudation in
the operation cavity, the oxygen flow was gradually reduced until the
removal. During this period, we observed that if the oxygen flow rate
was adjusted to more than 4L/min, the operation cavity would be too dry.
It would induce the gauze adhere to the deep neck tissue, which was not
easy to separate. This kind of situation was not conducive to the growth
of granulation tissue and wound healing. Secondly, during the period of
aerobic treatment, the neck bandage should be loose, so as to facilitate
the outflow of oxygen, to prevent the infection from spreading to the
surrounding spaces due to excessive air pressure. The oxygen flow tube
should not be plugged into the dead cavity, avoiding serious
consequences. When the drainage fluid is clear or reduced to less than
10 ml, the drainage should be removed during using negative pressure
drainage with suture of operation cavity. If the pus cavity is connected
with the gas incision stoma, it needs to be blocked by suture (Figure.
3F, shown by the yellow arrow), so as to avoid the sputum drainage into
the infection cavity during negative pressure drainage. For this kind of
patients, the previous treatment methods are mostly incision and
drainage of pus, dressing change 1 to 2 times a day, until the pus
disappeared or granulation tissue filled the operation cavity, suture
the incision, or even change dressing until the incision healed. It
often takes half a month to a few months. This patient underwent
postoperative dressing change for only 4 days, and the volume and
situation of drainage fluid were observed daily after negative pressure
drainage. It greatly reduces the psychological and physical trauma of
patients and the workload of clinicians.
Patients should be paid close attention to the general situation,
especially blood glucose and blood pressure. Without good blood glucose
control, ketoacidosis, hypertonic syndrome, lactic acidosis or
hypoglycemia may occur, which is not conducive to the follow-up
treatment. In this study, 25 cases were accompanied with type 2
diabetes, accounting for 49.0%. Most of them had large fluctuation of
blood glucose level with poor control. After admission, we should
actively contact doctors of the Department of Endocrinology for
consultation, adjust the application of hypoglycemic drugs, especially
for patients with oral feeding difficulties and needing nasal feeding
nutrition. We chose insulin to control blood glucose as much as
possible. According to the results of blood glucose monitoring, the type
and dosage of insulin should be adjusted in time. Nutritional support is
very important for patients with DNSI. Because the lesions are located
in the neck and oropharynx, many patients have oral feeding
difficulties. In this regard, we can indwelling gastric tube for nasal
feeding nutrition and guide the family members of patients with nasal
feeding knowledge, also can use nutrition liquid 500ml-1500ml every day.
During this period, blood routine and biochemical indexes should be
reexamined daily or every other day to understand the infection index,
electrolyte status and nutritional status of patients. For patients with
poor general conditions, especially those with poor cardiopulmonary
function, they need to be transferred to the intensive care department
for further treatment.
The most effective treatment for DNSI is incision and antibiotic therapy
(9-11). Flushing and dressing change, intermittent suture of wound and
the negative pressure drainage of pus cavity were used. For first-line
clinical doctors, more doctors still use traditional flushing and
dressing change treatment. It was reported that the drainage tube placed
in the pus cavity was used to treat the infections of the deep neck
space, and had obtained good efficacy and cosmetology effect(12,13).
This method is a good way for small single abscess. We consider that
when the abscess in the deep neck spaces has formed in a large area,
incision and drainage should be carried out as early as possible,
especially for the multiple lacunar abscess. During the operation, all
the septa should be separated as far as possible without dead space
left, and the necrotic tissue should be completely removed while the
important nerves and blood vessels are preserved.
If the abscess has not yet formed or the scope is small, the patients
can be followed up by CT examination or color Doppler ultrasound
examination according to the general situation. It was reported that
combined with thorough clinical examination, the accuracy of CT imaging
in differentiating drainable abscess and cellulitis can reach
89%(14-15). Mark et al reported that the diameter of abscess
> 2.5 cm on imaging examination was an important predictor
of surgical intervention [15]. This indiator has
important value for clinical treatment. For patients who choose
conservative treatment, if the scope of abscess is not reduced or
further expanded within 48 hours, incision and drainage should be
carried out as soon as possible. In any case, once the diagnosis is
made, we should first closely observe the patient’s breathing condition,
and tracheotomy should be performed as soon as possible if dyspnea
occurs. Local anesthesia is recommended with the help of an
anesthesiologist because the patient may have airway distortion, tissue
stiffness, and limited mouth opening. Because intubate may make the
damaged airway worse, so we should not use laryngoscope tracheal
intubation(16). Case 2 diagnosed as deep neck space infection only
underwent tracheotomy under local anesthesia. After active
anti-inflammatory treatment and close follow-up CT examination, she was
found that the scope of inflammation did not further expand, and
gradually reduced. Finally, after the inflammation disappeared, the
tracheotomy cannula was removed. And the patient finally recovered. The
treatment method avoids the pain of debridement and dressing change.