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Percutaneous dilatational tracheostomy. Is bronchoscopy necessary? A randomized clinical trial
Trends in Anaesthesia and Critical Care 15 (2017) 20e24
Contents lists available at ScienceDirect
Trends in Anaesthesia and Critical Care journal homepage: www.elsevier.com/locate/tacc
Percutaneous dilatational tracheostomy. Is bronchoscopy necessary? A randomized clinical trial* Adel Taha a, Amr S. Omar b, c, * a
Critical Care Department, Mafraq Hospital, Abu Dhabi, United Arab Emirates Critical Care Department, Beni Suef University Hospital, Egypt c Heart Hospital Hamad Medical Corporation, Doha, Qatar b
a r t i c l e i n f o
a b s t r a c t
Article history: Received 4 January 2017 Received in revised form 19 May 2017 Accepted 26 June 2017
Background: The widespread attraction of percutaneous dilatational tracheostomy (PDT) is increasing in modern intensive care units (ICU). Bronchoscopic guidance seems to secure the safety of the technique. Aim of the work: To address whether the technique could be accomplished safely without bronchospic guidance. Methods: We compared bronchoscopic guided versus blindly inserted PDT in a randomized clinical trial study utilizing single dilator techniques carried over 176 patients. The bronchoscope was reserved as a rescue method when tracheal cannulation could not be achieved after 2 trials in the blind group. Results: One hundred and seventy six patients were enroled, blind technique was utilized in 89 patients, in the first attempt tracheal puncture was achieved in 62 patients (70%), while 27 patients (30%) required a second attempt to puncture the trachea. Within this group bronchoscope was not demanded. Major complications in terms of major blood loss with transfusion need, vascular injury, surgical emphysema, pneumothorax, pneumomediastinum) were not reported among both groups. The mean time of the procedure was 5 and 12 min in the in the blind and bronchoscope groups respectively. Arterial oxygen desaturation that responded to increasing FiO2 occurred in twenty-one out of 87 patients in the bronchoscopy group, however this was not reported among the blind group. The mean delay time of the procedure was 1 day due to unavailability of the bronchoscope. Conclusions: Safety of the blind PDT is at least equivalent to the bronchoscopic guided one when experience exists. No specific superior advantage reported from the later technique and the waiting time for the scope availability may unnecessarily delay the procedure. © 2017 Elsevier Ltd. All rights reserved.
Keywords: Percutaneous tracheostomy Bronchoscope
1. Background Tracheostomy is recognized as one of the oldest surgical procedures documented for establishing airway access dating back approximately 4000 years. The safety and viability of the tracheostomy procedure was not considered until the early 20th century when clear guidelines were introduced by Chevalier Jackson. The growing interest in minimally invasive procedures made technical
* From the Department of critical care medicine/ Mafraq Hospital, Abu Dhabi, United Arab Emirates. * Corresponding author. Department of Cardiothoracic Surgery/Cardiac Anesthesia & ICU Section, Heart Hospital, Hamad Medical Corporation, Doha 3050, Qatar. E-mail addresses: [email protected] (A. Taha), [email protected] (A.S. Omar).
http://dx.doi.org/10.1016/j.tacc.2017.06.002 2210-8440/© 2017 Elsevier Ltd. All rights reserved.
progress of the standard open tracheostomy over the last half century. Since Ciaglia et al. introduced the percutaneous dilatational tracheostomy (PDT) in 1985, it became increasingly popular and has gained widespread acceptance in many intensive care units (ICU) and trauma centers as a viable alternative approach [1]. Over the last two decades, investigators went through comparing several techniques of PDT versus the open surgical tracheostomy. Most studies favor PDT over the open surgical technique in the view of lower complications rates [2]. Proponents of PDT plead the smaller incisions, less tissue trauma, reduced wound infection and increased cost effectiveness [3]. Furthermore, a recent meta-analysis by Higgins and Punthakee demonstrated no significant difference when comparing overall complications, with a trend toward favoring percutaneous method [4]. Compared to translaryngeal intubation, there is surprisingly low quality data in terms of overall outcome and guidelines that drive
A. Taha, A.S. Omar / Trends in Anaesthesia and Critical Care 15 (2017) 20e24
the practice of PDT. Therefore the guiding recommendations are based on expert opinion [5]. Few investigators compared bronchoscopic versus blind techniques, de Tejada reported that bronchoscopic guidance shortens the procedure time and reduces overall complications [6] The possible complications related to the tracheostomy procedure included bleeding, false track, esophageal perforation, pneumothorax and conversion to surgical tracheostomy. The given minor complications included bleeding, subcutaneous emphysema, air leakage cuff, puncturing endotracheal tube or posterior tracheal wall, accidental detubation and hypotension [7]. In a randomized controlled clinical trial comparing both techniques the authors found that procedure time was shorter with no hypercapnia in the blind technique, where bronschoscopc guidance was associated with reduced overall complication and number of tracheal puncture trials [8]. Another possible advantage of the bronchoscopic guided technique is that it permits lower airway secretions sampling giving accurate cultural diagnosis [9]. Tracheostomy plays an important role in the management of airways in this population, however, the timing remains debatable in the view of practice preferences. [10] The decision to proceed to tracheostomy is often made only if the patient could not be extubated within 10e14 days or more [11]. With bronchoscopy, not only is the initial placement of the needle fully controlled, but also all steps of the PDT. The trachea is visualized from inside, and the progress of each introduced devices (i.e., needle, guidewire, and cannula) would minimize injury, especially of the membranous tracheal posterior wall [12]. The injury risk is reported to be high without bronchoscopic support as movement of the used devices introduced into the tracheal lumen would be extremely limited [13]. Anatomical guided guidance is safe in PDT and the procedure is usually done at the bedside in the ICU. Despite the higher safety profile of the bronchoscopic guided PDTs, it is time consuming, could be associated with delaying the
21
procedure and associated with increase ICU expenses [14]. Safety of PDT in absence of bronchoscopic guidance is questionable. [15]. The reported overall mortality rates were 0.65% for bronchopscopic guided and 0.52%, for blind PDT [16]. Previous randomized trial favoring bronchoscopic guided technique may be underpowered or have small sample volume. Bronchoscopic guidance may not be available in some institutions. 2. Objectives This is a non-inferiority trial aiming to compare the safety of anatomically guided versus bronchoscopic guided percutaneous tracheostomy. We identified technique safety as our end point. 3. Methods Between July 2008 and July 2011, 186 patients were screened from which 178 were enroled (Fig. 1) to receive percutaneous tracheostomy at Mafraq hospital/UAE after approval of the ethical committee. Patients were simply randomized to either blind or bronchoscopic assisted techniques (where an even number was assigned to blind and an odd number was assigned to bronchoscopy) after initial approval and signing the informed consent. The study was conducted over three years as there was no enough studies to decide on the sample volume. The procedure was performed after obtaining the informed consent from the closest relative of the patient and single dilator technique was utilized in all of them. The trial got agreement from the ethical committee (2,008,070,119). Inability to protect the airways, anticipated ventilator dependence or prolonged tracheal toilet was the main indications for the percutaneous tracheostomy. Excluded from the study were
Fig. 1. Study enrollment and randomization.
22
A. Taha, A.S. Omar / Trends in Anaesthesia and Critical Care 15 (2017) 20e24
1. Patients aged younger than 18 years as per corporate regulations. 2. Emergency airway access requirement due to acute compromise. Anatomical neck distortion due to associated hematoma, torticollis, or thyromegaly (second or third degree). 3. Obscured neck landmarks associated with morbid obesity. 4. Medically uncorrectable blood disorder (more than 1.5 times reference range of prothrombin time or activated partial thromboplastin or platelet count less than 50,000/mL). 5. High positive end-expiratory pressure (PEEP) requirements more than 10 cm of water or high FIO2 (more than 0.6) to maintain adequate oxygenation.
intermediate dilator and guidewire was removed, followed by inflating the tracheotomy tube cuff then the breathing circuit was connected. Air entry into the lungs was checked by chest auscultation and capnometry. 3.2. Bronchocopic guided technique When the procedure was carried on under bronchoscopy, the initial placement of the needle, advancement of the guidewire, dilatation, and placement of the tracheostomy tube and the withdrawal of endotracheal tube was fully controlled under direct visualization. 3.3. Outcome measures
3.1. Blind technique Two skilled physicians performed the procedure under complete aseptic precautions at bedside with third physician used to manage the airways (to pull the tube up before tracheal puncture). The electrocardiogram, blood pressure and arterial oxygen saturation were monitored continuously throughout the procedure. Local anaesthesia, sedation, and muscle relaxant were used during the procedure. The patient was positioned supine with a slight head-up tilt and neck hyperextended by a pillow underneath the shoulders. Endotracheal and pharyngeal suction performed then, the endotracheal tube cuff deflated and the tube was withdrawn making the cuff was just below the vocal cords. The cuff inflated in this position to provide a good seal. A single dilator Tracoe Experc Tracheostomy set (Tracoe Medical, GmbH, Frankfurt) was used (Fig. 1). Hypoxia is considered when the arterial oxygen saturation (SaO2) is less than 90% on mechanical ventilation. After adequate neck cleaning with antiseptic solution and proper draping, the anatomical landmarks identified halfway between the cricoid cartilage and the manubrium sterni, the skin was anasthesized with 1% lidocaine with 1:100,000 epinephrine. Transverse skin incision from 1 to 1.5 cm was made at the level of the first and second tracheal rings, and then blunt dissection of the midline was performed. A 14-gauge angio-catheter was introduced between the first and second or the second and third tracheal rings. The guidewire was then introduced when air aspirated from the syringe. The Tracoe Experc Tracheostomy dilator was advanced over the guidewire until the stroma is dilated to an adequate diameter (36-F to 38-F). Once dilation was achieved, the tracheotomy cannula was assembled with appropriate 1 of the 3 intermediate dilators. Once assembled, it was advanced over the guidewire until the cannula was in place within the tracheal lumen. The
We identified technique safety as our primary outcome in terms of early complications, while secondary outcome was the procedure time. Early complications were defined as complications within the first 24 h according to our institution policy and included minor or major bleeding, significant oxygen desaturation, and pneumothorax. 3.4. Follow up Routine tracheostomy care was provided through antiseptic manipulation. Follow up of all patients was done on weekly basis during their hospital stay and on monthly basis when they were discharged for 6 months by the ICU team. Follow up included reporting any complications, like stromal infection and signs of posterior tracheal wall injury. Patients follow up and statistical analysis was kept blinded. No major complications (major blood loss that required blood transfusion, vascular injury, pneumothorax, pneumomediastinum) during the procedure. Minor bleeding occurred as an early complication in one patient that was managed conservatively with packs. No blood transfusion was necessary in this case. There were no other complications such as excessive purulent exudate at stoma or major bleeding. No patients randomized to the blind technique required cross-over to bronchscopic guidance. There were no long term complications related to the procedure reported in either group. The mean duration of the procedure in our patients i.e. from skin incision to successful insertion of tracheostomy tube was recorded and compared between both groups (Table 2). Due to the lack of bronchoscopic availability, bronchoscope group had a mean delay time of 1.06 ± 0.7 day.
Table 1 Demographic criteria among the studied groups. Variable
Blind technique group (Group I)
Bronchoscopy group (Group II)
P value
No Age Male: Female ratio BMI Anatomical difficulty Admission category Neurology COPD ALI Pneumonia Post operative Decision time (days) APACHE II score
89 (%) 46.3 ± 18.5 49:40 26.7 ± 4.6 1 (1.1)
87 (%) 45.9 ± 19.2 52:35 28 ± 5.2 1 (1.1)
0.8 0.7
56 12 9 8 4 10.2 ± 4.1 28 ± 7.1
61 8 6 6 6 9.6 ± 3 29.1 ± 7.8
COPD chronic obstructive pulmonary disease, ALI acute lung injury. APACHE acute physiology and chronic health evaluation sore.
0.7 0.9
0.6 0.7
A. Taha, A.S. Omar / Trends in Anaesthesia and Critical Care 15 (2017) 20e24
23
Table 2 The duration and complications related to the procedure. Variable
Blind technique group (Group I)
Bronchoscopy group (Group II)
P value
Duration (min) Post operative complications Early complications Minor bleeding Major bleeding Transient hypoxia Delay time (days) Successful cannulation 1st time 2nd time
5 ± 1.3 None
12.1 ± 5.6 None
0.04
1 No No No
No No 12 1.06 ± 0.7
57 (64) 32 (36)
81 (93) 6 (7)
4. Statistical analysis Quantitative data were presented using mean, standard deviation, where qualitative data were presented in frequency and percent. Normally distributed continuous variables were compared using Student's t-tests, where non-normally distributed continuous variables were compared using ManneWhitney tests, and categorical variables were compared using Chi squared tests. A twosided P-value <0.05 was counted as a statistically significant variable. All statistical analyses were performed using SPSS Version 16 software (SPSS Inc. Chicago, IL, USA). 5. Results One hundred and one males and 75 females with a mean age of 46 ± 18 years (range 19e77) were enroled in the study (Table 1). The majority of patients suffered from neurological disease (traumatic brain injury or cerebrovascular strokes) (117 patients). The decision to perform tracheostomy by PDT technique was taken within 10.2 ± 4.1 in group I and 9.6 ± 3 days after endotracheal intubation in group II. Both groups were matched regarding the mean acute physiology and chronic health evaluation score (APACHE II). The mean duration of the procedure in our patients i.e. from skin incision to successful insertion of tracheostomy tube was recorded and compared between both groups (Table 2). No major complications (major blood loss that required blood transfusion, vascular injury, pneumothorax, pneumomediastinum) during the procedure. Minor bleeding occurred as an early complication in one patient that was managed conservatively with packs. No blood transfusion was necessary in this case. There were no other complications such as excessive purulent exudate at stoma or major bleeding. Due to lack of bronchoscopic availability, the bronchoscope group had a mean delay time of 1.06 ± 0.7 day. 6. Discussion Tracheostomy is frequently performed in critically ill patients requiring prolonged mechanical ventilation [17]. The percutaneous tracheostomy is preferred over the conventional surgical tracheostomy, as it can be rapidly performed at the bedside with fewer complications [18]. Recently, Putensen et al. mentioned several advantages of percutaneous tracheostomy over surgical one including reduced stromal inflammation and infection, faster, and lower of intraprocedural risks with equal incidence of tracheal stenosis [19]. We hypothesise that PDT without tracheostomy could provide similar outcome to the bronchoscopic assisted one when experience of the performing physician exists. Strong evidence exists to support the use of fiberoptic bronchoscope to reduce the procedural complications [20,21]. This has
0.001
been mainly due to the fact that bronchoscopy can help to verify the safe placement of needle and guide wire [22]. However, a survey carried out by Cooper et al., in 1998 revealed that only 31.3% centers routinely use fiberoptic bronchoscopy during percutaneous tracheostomy [23]. This may be due to logistical reasons or related to some reports of increased airway pressure leading to its sequela such as increased intracranial pressure, pneumothorax and hypoxia associated with PDT [24,25]. Large posterior wall tear of trachea leading to tension pneumothorax has also been reported with bronchoscopic assisted percutaneous tracheostomy as a more serious complication [26]. Although, the incidence of perioperative complications has been reported to be similar with and without bronchoscopy (7% and 6% respectively), the complications were more serious in patients in whom bronchoscopy was not used. These included perforation of posterior tracheal wall and one death due to tension pneumothorax [27]. Bronchoscopy aid allows the precise positioning of the initial needle puncture in the anatomically preferred position; the level of puncture with a needle could be distinguished without skin incision by simultaneous supervision through the bronchoscope and the enforcement of a slight pressure to the skin over the trachea. High tracheal puncture could be associated with more complications; the later may be encountered in doing PDT without bronchoscopy as the level of the puncture is uncertain [27,28]. On the other hand too low a puncture may impose a risk of bleeding danger of accidentally cutting across some blood vessels if a large thyroidal gland is present that are positioned beneath [27,28]. Patients were simply randomized to receive either blind or bronchoscopic guided techniques. PDT was performed in 89 patients in our study using single dilator technique without the aid of bronchoscope and with bronchoscopic assistance in the other 87 patients. In our study, there was no accidental extubation, or cuff puncture. No hypoxic episodes were reported in the blind technique group, however hypoxic episodes were frequent in the bronchoscopy group 24% of patients. Bronchoscopy had been recommended since introduction of PDT technique [29]. Hassanin et al. concluded that the overall complication are much less with use of flexible bronchoscopy [8]. The other minor complication encountered was persistent oozing from the stromal site after the procedure in one patient. This is in contrast to some of the reports that have described a complication rate of 10% [17]. Since patients in our study were randomized to receive PDTs without bronchoscopic assistance, para-median puncture of trachea and superficial posterior tracheal wall injuries in this group could not be ruled out. However, long term follow up for 6 months of those patients did not reveal any signs of such complications. The duration of the procedure was also much shorter in the blind technique group (Mean: 5 ± 1.3 min in group I versus 12.1 ± 5.6 in group II), as compared to some other studies with duration of 4.3e13.6 min [30,31]. A mean delay time of 1.06 ± 0.7 day due to bronchoscopy unavailability was encountered
24
A. Taha, A.S. Omar / Trends in Anaesthesia and Critical Care 15 (2017) 20e24
in group II. Fifty seven patients in group I in our study were successfully cannulated from 1st puncture, 32 patients cannulated from the 2nd puncture and all patients had a good approximation of tissues with in a mean of 4.92 ± 1.6 days. This was concomitant to other study that showed reduced the number of trials of needle insertion with bronchoscopic assistance, while blind technique was better in shortening procedural time and avoidance of hypercapnia [8]. Cost reductions need to be also considered in favoring either of the techniques, Al-Ansari MA & Hijazi mentioned that routine utilization of flexible bronchoscopy in PDT is associated with more costs, the estimated cost for ICU stay range from 1000 to 7500USD per week [29]. We think that bronchoscopy could set to delay and lengthen the PDT procedure; although t is associated with more successful first puncture attempts. 7. Conclusions Safety of the blind PDT is at least equivalent to the bronchoscopic guided one when experience exists. No specific superior advantage reported from the later technique and the waiting time for the scope availability may unnecessarily delay the procedure. Abbreviation list ALI Acute lung injury CMV Controlled Mandatory Ventilation. ICU Intensive Care Unit. PDT Percutaneous Dilational Tracheostomy. PEEP Positive End Expiratory Pressure.
Author's contribution AT did the study design, shared in data collection, and performed the statistical analysis. AS, shared in data collection and helped in writing the manuscript. Key messages 1. Blind PDT is at least as safe as bronchoscopic assisted one. 2. Waiting for scope availability may delay the procedure. 3. Bronchoscope may unnecessarily interfere with the patients' oxygenation.
Conflict of interest The authors declare no conflict of interest concerning the materials or methods used in this study or the findings specified in this paper. Financial disclosure No external financial support was obtained. Study limitation One of the study limitations is being a single center study. The blind technique could be advocated when experienced physician is available. In our center, this service is consultant based. Larger studies would be recommended based on lack of power on our sample.
References [1] A. Ben-Nun, E. Altman, L.A. Best, Emergency percutaneous tracheostomy in trauma patients: an early experience, Ann. Thorac. Surg. 77 (3) (Mar 2004) 1045e1047. [2] P. Ciaglia, R. Firsching, C. Syniec, Elective percutaneous dilatational tracheostomy. A new simple bedside procedure; preliminary report, Chest 87 (6) (Jun 1985) 715e719. [3] B.D. Freeman, K. Isabella, J.P. Cobb, et al., A prospective, randomized study comparing percutaneous with surgical tracheostomy in critically ill patients, Crit. Care Med. 29 (5) (May 2001) 926e930. [4] K.M. Higgins, X. Punthakee, Meta-analysis comparison of open versus percutaneous tracheostomy, Laryngoscope 117 (3) (2007 Mar 1) 447e454. [5] N.R. MacIntyre, Evidence-based guidelines for weaning and discontinuing ventilatory support: a collective task force facilitated by the american college of chest physicians; the american association for respiratory care; and the american college of critical care medicine, Chest J. 120 (6_suppl) (2001 Dec 1) 375Se396S. [6] J.A. de Tejada, R.M. Punter, I.C. Barber, R.A. Ruiz, J.A. Marco, O.R. Naranjo, Outcomes and complications of bronchoscopy-guided percutaneous dilatational tracheostomy, Eur. Respir. J. 38 (Suppl 55) (2011 Sep 1) 3716. [7] D.A. Dongelmans, A. van der Lely, R. Tepaske, R. Tepaske, M.J. Schultz, Complications of percutaneous dilating tracheostomy, Crit. Care Lond. 8 (2004) 397e398. [8] E.G. Hassanin, A.A. Elgnady, M.S. El-Hoshy, B.N. Beshey, A.M. Abdelhady, Fiberoptic bronchoscopic guidance in percutaneous dilational tracheotomy, Egypt. J. Tubercul. Dis. Chest 62 (3) (2013 Jul 31) 519e527. [9] O. Afolabi-Brown, M. Marcus, P. Speciale, M. Pagala, M. Kazachkov, Bronchoscopic and nonbronchoscopic methods of airway culturing in tracheostomized children, Respir. care 59 (4) (2014 Apr 1) 582e587. [10] J. Griffiths, V.S. Barber, L. Morgan, J.D. Young, Systematic review and metaanalysis of studies of the timing of tracheostomy in adult patients undergoing artificial ventilation, Bmj 330 (7502) (2005 May 26) 1243. [11] D. Young, D.A. Harrison, B.H. Cuthbertson, K. Rowan, Effect of early vs late tracheostomy placement on survival in patients receiving mechanical ventilation: the TracMan randomized trial, Jama 309 (20) (2013 May 22) 2121e2129. [12] I. Lesnik, W. Rappaport, J. Fulginiti, D. Witzke, The role of early tracheostomy in blunt, multiple organ trauma, Am. Surg. 58 (1992) 346e349. [13] M. Gründling, D. Pavlovic, S.O. Kuhn, et al., Is the method of modified percutaneous tracheostomy without bronchoscopic guidance really simple and safe? Chest 128 (2005) 3774e3775. [14] V. Boonsarngsuk, S. Kiatboonsri, S. Choothakan, Percutaneous dilatational tracheostomy with bronchoscopic guidance: ramathibodi experience, J Med assoc thai. 90 (8) (2007 Aug) 1512e1517. [15] M.M. Maddali, M. Pratap, J. Fahr, et al., Percutaneous tracheostomy by guidewire dilating forceps technique: review of 98 patients, J. Postgrad. Med. 47 (2001) 100. [16] D.M. Powell, P.D. Price, L.A. Forrest, Review of percutaneous tracheostomy, Laryngoscope 108 (1998) 170e177. [17] J.E. Heffner, K.S. Miller, S.A. Sahn, Tracheostomy in the intensive care unit. Part 1. Indications, technique, management, Chest 90 (1986) 269e274. [18] N. van Heerbeek, B.G. Fikkers, F.J. van den Hoogen, et al., The guide wire dilating forceps technique of percutaneous tracheostomy, Am. J. Surg. 177 (1999) 311e315. [19] C. Putensen, N. Theuerkauf, U. Guenther, et al., Percutaneous and surgical tracheostomy in critically ill adult patients: a meta-analysis, Crit. Care 18 (6) (2014 Dec 19) 544. [20] K.S. Moe, S.J. Stoeckli, S. Schmid, et al., Percutaneous tracheostomy: a comprehensive evaluation, Ann. Otol. Rhinol. Laryngol. 108 (1999) 384e391. [21] N.A. Atweh, P.P. Possenti, P.F. Caushaj, et al., Dilational percutaneous tracheostomy: modification of technique, J. Trauma 47 (1999) 142e144. [22] D. Marelli, A. Paul, S. Manolidis, et al., Endoscopic guided percutaneous tracheostomy: early results of a consecutive trial, J. Trauma 30 (1990) 433e435. [23] R.M. Cooper, Use and safety of percutaneous tracheostomy in intensive care. Report of a postal survey of ICU practice, Anaesthesia 53 (1998) 1209e1212. [24] F. Blot, C. Melot, Indications, timing, and techniques of tracheostomy in 152 French ICUs, Chest J. 127 (4) (2005 Apr 1) 1347e1352. [25] P.B. Hazard, H.E. Garrett Jr., J.W. Adams, et al., Bed side percutaneous tracheostomy: experience with 55 elective procedures, Ann. Thorac. Surg. 46 (1988) 63e67. [26] W.H. Fish, N.O. Boheimer, D.R. Cadle, et al., A life threatening complication following percutaneous tracheostomy, Clin. Intensive Care 7 (1996) 206e208. [27] R. Dollner, M. Verch, P. Schweiger, et al., Laryngotracheoscopic findings in long-term follow-up after Griggs tracheostomy, Chest 122 (2002 Jul) 206e212. [28] L.W. van Heurn, P.H. Theunissen, G. Ramsay, et al., Pathologic changes of the trachea after percutaneous dilatational tracheotomy, Chest 109 (1996) 1466e1469. [29] M.A. Al-Ansari, M.H. Hijazi, Clinical review: percutaneous dilatational tracheostomy, Crit. Care 10 (1) (2005) 202. [30] J.M. Anon, V. Gomez, M.P. Escuela, et al., Percutaneous tracheostomy : comparison of Ciaglia and Griggs techniques, Crit. Care 4 (2000) 124e128. [31] K.O. Sun, Portex percutaneous tracheostomy kit, Anaesthesia 50 (1995) 748.
Contents lists available at ScienceDirect
Trends in Anaesthesia and Critical Care journal homepage: www.elsevier.com/locate/tacc
Percutaneous dilatational tracheostomy. Is bronchoscopy necessary? A randomized clinical trial* Adel Taha a, Amr S. Omar b, c, * a
Critical Care Department, Mafraq Hospital, Abu Dhabi, United Arab Emirates Critical Care Department, Beni Suef University Hospital, Egypt c Heart Hospital Hamad Medical Corporation, Doha, Qatar b
a r t i c l e i n f o
a b s t r a c t
Article history: Received 4 January 2017 Received in revised form 19 May 2017 Accepted 26 June 2017
Background: The widespread attraction of percutaneous dilatational tracheostomy (PDT) is increasing in modern intensive care units (ICU). Bronchoscopic guidance seems to secure the safety of the technique. Aim of the work: To address whether the technique could be accomplished safely without bronchospic guidance. Methods: We compared bronchoscopic guided versus blindly inserted PDT in a randomized clinical trial study utilizing single dilator techniques carried over 176 patients. The bronchoscope was reserved as a rescue method when tracheal cannulation could not be achieved after 2 trials in the blind group. Results: One hundred and seventy six patients were enroled, blind technique was utilized in 89 patients, in the first attempt tracheal puncture was achieved in 62 patients (70%), while 27 patients (30%) required a second attempt to puncture the trachea. Within this group bronchoscope was not demanded. Major complications in terms of major blood loss with transfusion need, vascular injury, surgical emphysema, pneumothorax, pneumomediastinum) were not reported among both groups. The mean time of the procedure was 5 and 12 min in the in the blind and bronchoscope groups respectively. Arterial oxygen desaturation that responded to increasing FiO2 occurred in twenty-one out of 87 patients in the bronchoscopy group, however this was not reported among the blind group. The mean delay time of the procedure was 1 day due to unavailability of the bronchoscope. Conclusions: Safety of the blind PDT is at least equivalent to the bronchoscopic guided one when experience exists. No specific superior advantage reported from the later technique and the waiting time for the scope availability may unnecessarily delay the procedure. © 2017 Elsevier Ltd. All rights reserved.
Keywords: Percutaneous tracheostomy Bronchoscope
1. Background Tracheostomy is recognized as one of the oldest surgical procedures documented for establishing airway access dating back approximately 4000 years. The safety and viability of the tracheostomy procedure was not considered until the early 20th century when clear guidelines were introduced by Chevalier Jackson. The growing interest in minimally invasive procedures made technical
* From the Department of critical care medicine/ Mafraq Hospital, Abu Dhabi, United Arab Emirates. * Corresponding author. Department of Cardiothoracic Surgery/Cardiac Anesthesia & ICU Section, Heart Hospital, Hamad Medical Corporation, Doha 3050, Qatar. E-mail addresses: [email protected] (A. Taha), [email protected] (A.S. Omar).
http://dx.doi.org/10.1016/j.tacc.2017.06.002 2210-8440/© 2017 Elsevier Ltd. All rights reserved.
progress of the standard open tracheostomy over the last half century. Since Ciaglia et al. introduced the percutaneous dilatational tracheostomy (PDT) in 1985, it became increasingly popular and has gained widespread acceptance in many intensive care units (ICU) and trauma centers as a viable alternative approach [1]. Over the last two decades, investigators went through comparing several techniques of PDT versus the open surgical tracheostomy. Most studies favor PDT over the open surgical technique in the view of lower complications rates [2]. Proponents of PDT plead the smaller incisions, less tissue trauma, reduced wound infection and increased cost effectiveness [3]. Furthermore, a recent meta-analysis by Higgins and Punthakee demonstrated no significant difference when comparing overall complications, with a trend toward favoring percutaneous method [4]. Compared to translaryngeal intubation, there is surprisingly low quality data in terms of overall outcome and guidelines that drive
A. Taha, A.S. Omar / Trends in Anaesthesia and Critical Care 15 (2017) 20e24
the practice of PDT. Therefore the guiding recommendations are based on expert opinion [5]. Few investigators compared bronchoscopic versus blind techniques, de Tejada reported that bronchoscopic guidance shortens the procedure time and reduces overall complications [6] The possible complications related to the tracheostomy procedure included bleeding, false track, esophageal perforation, pneumothorax and conversion to surgical tracheostomy. The given minor complications included bleeding, subcutaneous emphysema, air leakage cuff, puncturing endotracheal tube or posterior tracheal wall, accidental detubation and hypotension [7]. In a randomized controlled clinical trial comparing both techniques the authors found that procedure time was shorter with no hypercapnia in the blind technique, where bronschoscopc guidance was associated with reduced overall complication and number of tracheal puncture trials [8]. Another possible advantage of the bronchoscopic guided technique is that it permits lower airway secretions sampling giving accurate cultural diagnosis [9]. Tracheostomy plays an important role in the management of airways in this population, however, the timing remains debatable in the view of practice preferences. [10] The decision to proceed to tracheostomy is often made only if the patient could not be extubated within 10e14 days or more [11]. With bronchoscopy, not only is the initial placement of the needle fully controlled, but also all steps of the PDT. The trachea is visualized from inside, and the progress of each introduced devices (i.e., needle, guidewire, and cannula) would minimize injury, especially of the membranous tracheal posterior wall [12]. The injury risk is reported to be high without bronchoscopic support as movement of the used devices introduced into the tracheal lumen would be extremely limited [13]. Anatomical guided guidance is safe in PDT and the procedure is usually done at the bedside in the ICU. Despite the higher safety profile of the bronchoscopic guided PDTs, it is time consuming, could be associated with delaying the
21
procedure and associated with increase ICU expenses [14]. Safety of PDT in absence of bronchoscopic guidance is questionable. [15]. The reported overall mortality rates were 0.65% for bronchopscopic guided and 0.52%, for blind PDT [16]. Previous randomized trial favoring bronchoscopic guided technique may be underpowered or have small sample volume. Bronchoscopic guidance may not be available in some institutions. 2. Objectives This is a non-inferiority trial aiming to compare the safety of anatomically guided versus bronchoscopic guided percutaneous tracheostomy. We identified technique safety as our end point. 3. Methods Between July 2008 and July 2011, 186 patients were screened from which 178 were enroled (Fig. 1) to receive percutaneous tracheostomy at Mafraq hospital/UAE after approval of the ethical committee. Patients were simply randomized to either blind or bronchoscopic assisted techniques (where an even number was assigned to blind and an odd number was assigned to bronchoscopy) after initial approval and signing the informed consent. The study was conducted over three years as there was no enough studies to decide on the sample volume. The procedure was performed after obtaining the informed consent from the closest relative of the patient and single dilator technique was utilized in all of them. The trial got agreement from the ethical committee (2,008,070,119). Inability to protect the airways, anticipated ventilator dependence or prolonged tracheal toilet was the main indications for the percutaneous tracheostomy. Excluded from the study were
Fig. 1. Study enrollment and randomization.
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A. Taha, A.S. Omar / Trends in Anaesthesia and Critical Care 15 (2017) 20e24
1. Patients aged younger than 18 years as per corporate regulations. 2. Emergency airway access requirement due to acute compromise. Anatomical neck distortion due to associated hematoma, torticollis, or thyromegaly (second or third degree). 3. Obscured neck landmarks associated with morbid obesity. 4. Medically uncorrectable blood disorder (more than 1.5 times reference range of prothrombin time or activated partial thromboplastin or platelet count less than 50,000/mL). 5. High positive end-expiratory pressure (PEEP) requirements more than 10 cm of water or high FIO2 (more than 0.6) to maintain adequate oxygenation.
intermediate dilator and guidewire was removed, followed by inflating the tracheotomy tube cuff then the breathing circuit was connected. Air entry into the lungs was checked by chest auscultation and capnometry. 3.2. Bronchocopic guided technique When the procedure was carried on under bronchoscopy, the initial placement of the needle, advancement of the guidewire, dilatation, and placement of the tracheostomy tube and the withdrawal of endotracheal tube was fully controlled under direct visualization. 3.3. Outcome measures
3.1. Blind technique Two skilled physicians performed the procedure under complete aseptic precautions at bedside with third physician used to manage the airways (to pull the tube up before tracheal puncture). The electrocardiogram, blood pressure and arterial oxygen saturation were monitored continuously throughout the procedure. Local anaesthesia, sedation, and muscle relaxant were used during the procedure. The patient was positioned supine with a slight head-up tilt and neck hyperextended by a pillow underneath the shoulders. Endotracheal and pharyngeal suction performed then, the endotracheal tube cuff deflated and the tube was withdrawn making the cuff was just below the vocal cords. The cuff inflated in this position to provide a good seal. A single dilator Tracoe Experc Tracheostomy set (Tracoe Medical, GmbH, Frankfurt) was used (Fig. 1). Hypoxia is considered when the arterial oxygen saturation (SaO2) is less than 90% on mechanical ventilation. After adequate neck cleaning with antiseptic solution and proper draping, the anatomical landmarks identified halfway between the cricoid cartilage and the manubrium sterni, the skin was anasthesized with 1% lidocaine with 1:100,000 epinephrine. Transverse skin incision from 1 to 1.5 cm was made at the level of the first and second tracheal rings, and then blunt dissection of the midline was performed. A 14-gauge angio-catheter was introduced between the first and second or the second and third tracheal rings. The guidewire was then introduced when air aspirated from the syringe. The Tracoe Experc Tracheostomy dilator was advanced over the guidewire until the stroma is dilated to an adequate diameter (36-F to 38-F). Once dilation was achieved, the tracheotomy cannula was assembled with appropriate 1 of the 3 intermediate dilators. Once assembled, it was advanced over the guidewire until the cannula was in place within the tracheal lumen. The
We identified technique safety as our primary outcome in terms of early complications, while secondary outcome was the procedure time. Early complications were defined as complications within the first 24 h according to our institution policy and included minor or major bleeding, significant oxygen desaturation, and pneumothorax. 3.4. Follow up Routine tracheostomy care was provided through antiseptic manipulation. Follow up of all patients was done on weekly basis during their hospital stay and on monthly basis when they were discharged for 6 months by the ICU team. Follow up included reporting any complications, like stromal infection and signs of posterior tracheal wall injury. Patients follow up and statistical analysis was kept blinded. No major complications (major blood loss that required blood transfusion, vascular injury, pneumothorax, pneumomediastinum) during the procedure. Minor bleeding occurred as an early complication in one patient that was managed conservatively with packs. No blood transfusion was necessary in this case. There were no other complications such as excessive purulent exudate at stoma or major bleeding. No patients randomized to the blind technique required cross-over to bronchscopic guidance. There were no long term complications related to the procedure reported in either group. The mean duration of the procedure in our patients i.e. from skin incision to successful insertion of tracheostomy tube was recorded and compared between both groups (Table 2). Due to the lack of bronchoscopic availability, bronchoscope group had a mean delay time of 1.06 ± 0.7 day.
Table 1 Demographic criteria among the studied groups. Variable
Blind technique group (Group I)
Bronchoscopy group (Group II)
P value
No Age Male: Female ratio BMI Anatomical difficulty Admission category Neurology COPD ALI Pneumonia Post operative Decision time (days) APACHE II score
89 (%) 46.3 ± 18.5 49:40 26.7 ± 4.6 1 (1.1)
87 (%) 45.9 ± 19.2 52:35 28 ± 5.2 1 (1.1)
0.8 0.7
56 12 9 8 4 10.2 ± 4.1 28 ± 7.1
61 8 6 6 6 9.6 ± 3 29.1 ± 7.8
COPD chronic obstructive pulmonary disease, ALI acute lung injury. APACHE acute physiology and chronic health evaluation sore.
0.7 0.9
0.6 0.7
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Table 2 The duration and complications related to the procedure. Variable
Blind technique group (Group I)
Bronchoscopy group (Group II)
P value
Duration (min) Post operative complications Early complications Minor bleeding Major bleeding Transient hypoxia Delay time (days) Successful cannulation 1st time 2nd time
5 ± 1.3 None
12.1 ± 5.6 None
0.04
1 No No No
No No 12 1.06 ± 0.7
57 (64) 32 (36)
81 (93) 6 (7)
4. Statistical analysis Quantitative data were presented using mean, standard deviation, where qualitative data were presented in frequency and percent. Normally distributed continuous variables were compared using Student's t-tests, where non-normally distributed continuous variables were compared using ManneWhitney tests, and categorical variables were compared using Chi squared tests. A twosided P-value <0.05 was counted as a statistically significant variable. All statistical analyses were performed using SPSS Version 16 software (SPSS Inc. Chicago, IL, USA). 5. Results One hundred and one males and 75 females with a mean age of 46 ± 18 years (range 19e77) were enroled in the study (Table 1). The majority of patients suffered from neurological disease (traumatic brain injury or cerebrovascular strokes) (117 patients). The decision to perform tracheostomy by PDT technique was taken within 10.2 ± 4.1 in group I and 9.6 ± 3 days after endotracheal intubation in group II. Both groups were matched regarding the mean acute physiology and chronic health evaluation score (APACHE II). The mean duration of the procedure in our patients i.e. from skin incision to successful insertion of tracheostomy tube was recorded and compared between both groups (Table 2). No major complications (major blood loss that required blood transfusion, vascular injury, pneumothorax, pneumomediastinum) during the procedure. Minor bleeding occurred as an early complication in one patient that was managed conservatively with packs. No blood transfusion was necessary in this case. There were no other complications such as excessive purulent exudate at stoma or major bleeding. Due to lack of bronchoscopic availability, the bronchoscope group had a mean delay time of 1.06 ± 0.7 day. 6. Discussion Tracheostomy is frequently performed in critically ill patients requiring prolonged mechanical ventilation [17]. The percutaneous tracheostomy is preferred over the conventional surgical tracheostomy, as it can be rapidly performed at the bedside with fewer complications [18]. Recently, Putensen et al. mentioned several advantages of percutaneous tracheostomy over surgical one including reduced stromal inflammation and infection, faster, and lower of intraprocedural risks with equal incidence of tracheal stenosis [19]. We hypothesise that PDT without tracheostomy could provide similar outcome to the bronchoscopic assisted one when experience of the performing physician exists. Strong evidence exists to support the use of fiberoptic bronchoscope to reduce the procedural complications [20,21]. This has
0.001
been mainly due to the fact that bronchoscopy can help to verify the safe placement of needle and guide wire [22]. However, a survey carried out by Cooper et al., in 1998 revealed that only 31.3% centers routinely use fiberoptic bronchoscopy during percutaneous tracheostomy [23]. This may be due to logistical reasons or related to some reports of increased airway pressure leading to its sequela such as increased intracranial pressure, pneumothorax and hypoxia associated with PDT [24,25]. Large posterior wall tear of trachea leading to tension pneumothorax has also been reported with bronchoscopic assisted percutaneous tracheostomy as a more serious complication [26]. Although, the incidence of perioperative complications has been reported to be similar with and without bronchoscopy (7% and 6% respectively), the complications were more serious in patients in whom bronchoscopy was not used. These included perforation of posterior tracheal wall and one death due to tension pneumothorax [27]. Bronchoscopy aid allows the precise positioning of the initial needle puncture in the anatomically preferred position; the level of puncture with a needle could be distinguished without skin incision by simultaneous supervision through the bronchoscope and the enforcement of a slight pressure to the skin over the trachea. High tracheal puncture could be associated with more complications; the later may be encountered in doing PDT without bronchoscopy as the level of the puncture is uncertain [27,28]. On the other hand too low a puncture may impose a risk of bleeding danger of accidentally cutting across some blood vessels if a large thyroidal gland is present that are positioned beneath [27,28]. Patients were simply randomized to receive either blind or bronchoscopic guided techniques. PDT was performed in 89 patients in our study using single dilator technique without the aid of bronchoscope and with bronchoscopic assistance in the other 87 patients. In our study, there was no accidental extubation, or cuff puncture. No hypoxic episodes were reported in the blind technique group, however hypoxic episodes were frequent in the bronchoscopy group 24% of patients. Bronchoscopy had been recommended since introduction of PDT technique [29]. Hassanin et al. concluded that the overall complication are much less with use of flexible bronchoscopy [8]. The other minor complication encountered was persistent oozing from the stromal site after the procedure in one patient. This is in contrast to some of the reports that have described a complication rate of 10% [17]. Since patients in our study were randomized to receive PDTs without bronchoscopic assistance, para-median puncture of trachea and superficial posterior tracheal wall injuries in this group could not be ruled out. However, long term follow up for 6 months of those patients did not reveal any signs of such complications. The duration of the procedure was also much shorter in the blind technique group (Mean: 5 ± 1.3 min in group I versus 12.1 ± 5.6 in group II), as compared to some other studies with duration of 4.3e13.6 min [30,31]. A mean delay time of 1.06 ± 0.7 day due to bronchoscopy unavailability was encountered
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in group II. Fifty seven patients in group I in our study were successfully cannulated from 1st puncture, 32 patients cannulated from the 2nd puncture and all patients had a good approximation of tissues with in a mean of 4.92 ± 1.6 days. This was concomitant to other study that showed reduced the number of trials of needle insertion with bronchoscopic assistance, while blind technique was better in shortening procedural time and avoidance of hypercapnia [8]. Cost reductions need to be also considered in favoring either of the techniques, Al-Ansari MA & Hijazi mentioned that routine utilization of flexible bronchoscopy in PDT is associated with more costs, the estimated cost for ICU stay range from 1000 to 7500USD per week [29]. We think that bronchoscopy could set to delay and lengthen the PDT procedure; although t is associated with more successful first puncture attempts. 7. Conclusions Safety of the blind PDT is at least equivalent to the bronchoscopic guided one when experience exists. No specific superior advantage reported from the later technique and the waiting time for the scope availability may unnecessarily delay the procedure. Abbreviation list ALI Acute lung injury CMV Controlled Mandatory Ventilation. ICU Intensive Care Unit. PDT Percutaneous Dilational Tracheostomy. PEEP Positive End Expiratory Pressure.
Author's contribution AT did the study design, shared in data collection, and performed the statistical analysis. AS, shared in data collection and helped in writing the manuscript. Key messages 1. Blind PDT is at least as safe as bronchoscopic assisted one. 2. Waiting for scope availability may delay the procedure. 3. Bronchoscope may unnecessarily interfere with the patients' oxygenation.
Conflict of interest The authors declare no conflict of interest concerning the materials or methods used in this study or the findings specified in this paper. Financial disclosure No external financial support was obtained. Study limitation One of the study limitations is being a single center study. The blind technique could be advocated when experienced physician is available. In our center, this service is consultant based. Larger studies would be recommended based on lack of power on our sample.
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