This was a retrospective, single-center, observational study of adult patients admitted to the neurosurgical intensive care unit (ICU) at Samsung Medical Center from January 2015 to December 2017. This study was approved by the Institutional Review Board of Samsung Medical Center (approval number: SMC 2018-09-011). The requirement for informed consent was waived due to its retrospective nature. We included adult patients admitted to the neurosurgical ICU who underwent tracheostomy during the study period. Those who were hospitalized for more than 14 days after tracheostomy were selected. Of these patients, we excluded patients under age 18, those who did not have brain injury, those who were discharged before 14 days after tracheostomy, and those who had insufficient medical records. Additionally, patients were excluded if they were admitted to departments other than neurosurgery.

We retrospectively reviewed all neurosurgery patients and neurocritcally ill patients admitted to the neurosurgery ICU who underwent tracheostomy during the study period. Regarding data associated with the tracheostomy procedure, initial success of tracheostomy and procedure time were investigated. Procedure time was defined as time from sterilization to connection of the tracheostomy tube with the mechanical ventilator after successful tracheostomy^11,12). Primary endpoint was procedure-induced complication. We investigated complications at insertion or during maintenance such as insertional injury, bleeding or hematoma, fracture of tracheal ring, cuff perforation, accidental decannulation, surgical conversion, hypoxemia, stomal ulcer, and ventilator-associated pneumonia (VAP). Regarding associated post-procedural bleeding complications, major bleeding was defined as bleeding that required cauterization, surgical treatment, or additional blood transfusion^11,12). Minor bleeding was defined as bleeding from the incision site that required dressing more than three times a day or epinephrine for local hemostasis. VAP was defined if patients received clinical diagnosis more than 48 hours after tracheotomy and received antimicrobial therapy with a new radiographical infiltrate and two of three clinical criteria: purulent secretions, fever, and leukocytosis or leukopenia^13,17). Secondary endpoints were initial success of tracheostomy and procedure time.

In this study, a neurointensivist or a neurosurgeon determined tracheostomy. Tracheostomy was considered if a patient was expected to be on prolonged mechanical ventilation, need air way protection, or show decreased sedation due to neurocritically ill and/or general critically conditions⁶⁾. We considered optimal candidates to be patients without (1) uncontrolled increased intracranial hypertension, or impending brainstem herniation; (2) acute phase of stroke or delayed cerebral ischemia in subarachnoid hemorrhage; (3) refractory status epilepticus; (4) fraction of inspired oxygen (FiO₂) greater than 0.6, positive end-expiratory pressure greater than 10 cm H₂O or plateau pressure greater than 40 cm H₂O; (5) requiring high-dose inotropes or vasopressors; (6) uncontrolled dysrrhythmia; (7) severe acidosis; (8) active bleeding; (9) active infection at the tracheostomy site or gross neck deformity⁶⁾. In PDT performed by a neurointensivist, patients received sedation and pain control with propofol or midazolam, intravenous analgesics with fentanyl and/or remifentanil, and topical analgesic with 1.5% lidocaine and 1:200,000 epinephrine¹⁷⁾. Especially, at least 30 minutes before the procedure, a continuously high dose infusion of propofol and bolus administration of osmotic agent were performed for patients with intracranial hypertension. Mechanical ventilation was controlled and FiO₂ was increased to 1.0. Before administration of neuromuscular blockade, the goal of sedation was to achieve Richmond Agitation Sedation Scale goal of negative 4 to 5^6,18). Anatomic landmarks were identified by palpation. We also used ultrasonography to identify and avoid large blood vessels near the tracheostomy site⁶⁾. PDT was performed using Ciaglia Blue Rhino^® (Cook Medical Inc., Bloomington, IN, USA) by a neurointensivist at bedside. Patients were kept in supine position with hyperextension of the neck during procedure. About 10 mm vertical incision was made at the inferior edge of the cricoid cartilage^5,11). Pretracheal soft tissues were bluntly dissected with a mosquito clamp if needed. Underlying trachea was then identified using a needle and introducer sheath under bronchoscopic visualization. After a J-tipped Seldinger wire was inserted through the introducer sheath into the trachea, the introducer sheath was then removed and dilation of the trachea and soft tissue was performed initially with a short dilator followed by a curved conical dilator^5,11). Finally, the tracheostomy tube was loaded onto an introducer dilator and gently inserted into the trachea over the guidewire through the dilated stoma and secured in place under bronchoscopic visualization⁹⁾.

CST was performed by a neurosurgeon or an otolaryngologist at bedside or surgical room. In tracheostomy performed by a neurointensivist or neurosurgeon, T-cannula was changed by neurosurgery residents at the first seven day. However, in CST performed by an otolaryngologist, T-cannula was changed by an otolaryngologist at the first three day after CST.

All data are presented as medians and interquartile ranges (IQRs) for continuous variables and numbers (percentages) for categorical variables. Data were compared using Mann-Whitney U test for continuous variables and Chi-squared test or Fisher’s exact test for categorical variables. All tests were two-sided and p-values < 0.05 were considered statistically significant. Data were analyzed using IBM SPSS statistics version 20 (IBM, Armonk, NY, USA).

A total of 118 patients were analyzed in this study. Among these patients, 61 underwent PDT by a neurointensivist and 57 patients underwent CST (36 by neurosurgeons, 21 by otolaryngologists) during the study. CST was performed in 4 (1 by neurosurgeons, 3 by otolaryngologists) patients in the operating room. Median age of patients was 61 (IQR 49–70) years. Of 118 patients, 51 (43.2%) were males. Elective surgery of brain tumor (33.1%) and intracranial hemorrhage (20.3%) were the most common reasons for ICU admission. There was no significant difference in age, gender, body mass index, comorbidities, Glasgow Coma Scale, or APACHE II score on ICU admission between the two groups except for reason for admission among baseline characteristics (Table 1). Difficult ventilator weaning or prolonged intubation (42.4%) and airway protection or prevent risk of aspiration (25.4%) were the most common reasons for tracheostomy. There were no significant differences in laboratory results of platelet count or coagulation on the day of tracheostomy between the two groups (Table 2).

There was no significant difference in initial success rate of tracheostomy between the two groups (p=0.110). However, procedural time was lengthier in CST than that in PDT (39.0 [30.0–60.0] min vs. 15.0 [11.0–23.0] min, p<0.001). Procedure-induced complications were more common in patients who underwent CST compared to those in patients who underwent PDT (26.3% vs. 11.5%, p=0.039). Although moderate or major bleeding occurred in five patients who underwent CST, only one patient had moderate bleeding in PDT. Especially, there were two respiratory arrests during procedure in CST. Although there was no infectious complication in patients who underwent PDT, two VAPs and seven wound infections occurred in patients who underwent CST. However, there was no significant difference in mortality or length of stay in the ICU or hospital between the two groups. There was no procedure-induced intracranial hypertension (intracranial pressure [ICP]>20 mmHg) during tracheostomy in either group.

Clinical outcomes were shown in Table 3