Comparison of criteria for elective tracheostomy in head and neck cancer surgery

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Comparison of criteria for elective

tracheostomy in head and neck cancer surgery

Filip Kissin

^1ABDEF

, Maciej Rysz

^1ABDEF

, Magdalena Budziszewska

^2CD

, Romuald Krajewski

^1DEF

1Head and Neck Cancer Department, National Institute of Oncology in Warsaw, Poland; Head: prof. Andrzej Kawecki MD PhD

2Faculty of Psychology, University of Warsaw, Poland

Article history: Received: 07.04.2021 Accepted: 01.05.2021 Published: 05.05.2021

ABSTRACT: Introduction: Elective tracheostomy before resection of a malignancy in head and neck region assures unobstructed ventilation during postoperative period but is associated with an increased risk of complications.

Aim: We aimed to evaluate retrospectively, how the application of elective tracheostomy scales would influence the frequency of tracheostomy in comparison with preoperative clinical judgement.

Methods: In 205 patients operated on from 2013 till 2017, theresection of a malignancy involved suprahyoid or pharyngeal muscles, neck dissection and flap reconstruction. The decision on elective tracheostomy was made on the clinical basis. Score for each patient in 3 published scales was calculated.

Results: In the study group 76 patients had elective tracheostomy at the outset of a resection procedure. Among 129 patients without elective tracheostomy, 9 had tracheostomy in the postoperative period. Indications for elective tracheostomy were calculated for scale I, II and III. Only in 120 patients the decision whether to perform elective tracheostomy would be identical in each scale.

Conclusion: Our results suggest that decisions to perform elective tracheostomy based on 3 scales show low specificity.

The factors used in the published scales should be evaluated in a prospective multicenter study.

KEYWORDS: elective tracheostomy, head and neck surgery, postoperative complications

Wkład autorów:

A – Projekt badań B – Zbieranie danych C – Analiza statystyczna D – Interpretacja danych E – Przygotowanie manuskryptu F – Analiza literatury G – Zbieranie funduszy

ABBREVIATIONS

CT – computed tomography ET – elective tracheostomy PPCs – postoperative pulmonary complications

PT – postoperative tracheostomy

INTRODUCTION

Resection of an oral or oropharyngeal malignancy is associated with a risk of airway obstruction in the postoperative period. Elective tracheostomy (ET) at the beginning of a resection procedure assures unobstructed ventilation and makes the postoperative course safer. However, tracheostomy is associated with complications such as tracheal stenosis, tracheomalacia, tracheoinnominate artery erosion, tracheoesophageal fistula, pneumonia, aspiration [1, 2]. It is also associated with longer hospitalization [3] and higher risk of surgical site infection [4].

Tracheostomy-related complications are significantly more com- mon in patients with earlier radiotherapy [5]. Postoperative pulmonary complications (PPCs) can occur in about 20% of patients or more with large ablative surgeries with microsurgical reconstruction [6–8]. Tracheostomy increases the risk of PPCs [6–9].

Inability to speak after tracheostomy reduces the quality of life,

negatively affects patients’ motivation and makes contacts with medical staff more difficult [10, 11]. Emergency tracheostomy leads to more complications in comparison to ET [12]. As many as 75% of patients report negative experiences with tracheostomy and would like to avoid it [13]. There are many risk factors of airway obstruction: edema, flap reconstruction that decreases the volume of the pharynx, resections of suprahyoid or pharyngeal muscles that could result in larynx reposition, possibility of airway collapse, anatomic changes. Carefully selected patients undergoing extensive ablative surgical procedures in the oral cavity and oropharynx can be safely managed with prolonged intubation [3, 9, 14, 15]. The decision to perform ET may be made on an individual basis and would depend on patient status, extent of planned resection and type of reconstruction. An extensive search of the PubMed, Medline, Cochrane, Science Direct da- tabase was performed to identify relevant articles published in the English language, using combinations of the search terms:

„postoperative tracheostomy”, „emergency tracheostomy”, „elective tracheostomy”, „risk factors’’, „head and neck’’, and „airway management’’. Scales based on sets of selected clinical variables that would help establishing indications for ET have been published [12, 15–18]. Among them three scales described in the literature were useful for retrospective analysis of our patients.

The purpose of this study was to assess retrospectively how the application of three published scales [12, 16, 17] would relate to the decisions made on the clinical basis.

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oropharynx cancer had oral intubation. Qualification for elective tracheostomy was made individually for each patient at the me- eting of the whole surgical team. Elective tracheostomy was indicated in patients who: required suprahyoid or pharyngeal muscle excision, had T3 or T4 tumour, had reconstruction with a bulky flap that could obstruct the airway, underwent salvage surgery after radiotherapy. In ET group 75 patients were intubated through the mouth before tracheostomy. One patient had naso-tracheal intubation and elective tracheostomy due to trismus. Four patients from the ET group had a history of previous tracheostomy. Ethical Committee approval was not required in this study.

TRACHEOSTOMY PROCEDURE

Elective tracheostomy was performed through II or III tracheal cartilage with or without thyroid isthmus ligation. In cases where the thyroid isthmus was not transected, it was retrac- ted upward. Standard tracheostomy tubes with cuff were used.

After 3 or 4 days the tube with cuff was changed for a tube without cuff. All tracheostomy procedures were performed by a surgical team from our department.

MATERIAL AND METHODS

A total of 275 consecutive patients were operated upon for oral and/or oropharyngeal cancers from 2013 till 2017 in our department. In this group 205 patients (149 men and 56 women, mean age 60, median age 60, range 32 to 84) had fulfilled inclu- sion criteria of our study: resection of a malignancy that involved suprahyoid or pharyngeal muscles, neck dissection and flap reconstruction. Patients with sarcomas and melanomas or without neck dissection were excluded from the study. Demographic and clinical data are presented in Tab. I.

Nine out of these 205 patients had a T1 tumor with lymph node metastases and required neck dissection and flap reconstruction. Histopathological diagnosis was squamous cell carcinoma in 198 cases, spindle cell carcinoma in 5, mucoepidermoid carcinoma in 1 and adenoid cystic carcinoma in 1 case. Thirty-five patients underwent radiotherapy before surgery and these were salvage cases. In 22 out of 35 irradiated patients primary tumor was located in the oropharynx and in 13/35 the primary site was tongue or oral cavity. Patients with floor of the mouth and tongue cancers underwent nasotracheal intubation and those with

Tab. I. Clinical data of the study group.

ET (76) Non-ET (129) Total (205) PT (9)*

Female/Male 19/57 37/92 56/149 0/9

Age (mean, range) 60 (42–79) 60,4 (32–84) 60 (32–84) 59,5 (34–83)

Tumor (TNM)

T1 0 9 9 0

T2 3 39 42 4

T3 2 6 8 2

T4 71 75 146 3

Location

Floor of the mouth 47 71 118 7

Tongue 20 42 62 0

Oropharynx 9 16 25 2

Previous radiotherapy 14 21 35 2

Bilateral neck dissection 48 40 88 2

Reconstruction

PMF 53 21 74 1

Submental flap 7 13 20 1

RFFF 7 38 45 5

FFF 3 8 11 0

Local 3 37 40 1

Temporalis muscle 2 0 2 0

ALT 1 7 8 1

ICFF 0 1 1 0

Other 0 4 4 0

* These patients are included in the non-ET group.

ET group – elective tracheostomy group; Non-ET group – no elective tracheotomy was performed; PT – Postoperative tracheostomy; ALT – Anterolateral Thigh Flap;

FFF – Free Fibula Flap; RFFF – Radial Forearm Free Flap; ICFF – Iliac Crest Free Flap; PMF – Pectoralis Myocutaneous Flap

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SCORING PROCEDURE

The first and the second author independently reviewed each patient’s record and assigned a score in each of three scales selected for analysis. Analyzed scales are presented in Tab. II. The initial agreement assessed by Cohen’s kappa was good for the second scale (k = 0.97), and slightly lower for the first (k = 0.88) and the third (k = 0.91). The differences in scores were resolved by discussion between the raters. Consensus was obtained on each score and on whether the patient would have indications for ET or not. Authors of scale I [16] added one point for a pa- thology seen in chest CT (computed tomography). In our material we used chest X ray and only 3 patients had chest CT before operation. Therefore, we had to exclude chest CT from scale I.

The cut-off point for elective tracheotomy in scale I was changed from 7 to 6 points. Scale II [17] required quantitative informa- tion on alcohol use and we could not obtain reliable data from the retrospective chart review. Only 18 out of 205 patients had sufficiently detailed record on alcohol use based on self-reports.

Therefore, we had to exclude alcohol use from scale 2 and we adjusted the cut-off point for tracheostomy indications of this scale to >= 5 instead of >= 7 points.

STATISTICAL ANALYSIS

Data were analyzed with SPSS® software. The predictive factors were nominal variables and their significance was assessed with x2 test. Association strength between the predictive factors and performed tracheotomy is reported as phi coefficient for two by two tables, and Cramer’s V for variables with more categories.

RESULTS

Nine out of 129 patients without an ET required tracheostomy during the postoperative period (1st to 10th postoperative day – postoperative tracheostomy). Indications for tracheostomy in these 9 patients were prolonged intubation (over 8 days) due to cardio- respiratory complications in 2 cases, revision of the microvascular anastomosis on the next day after surgery, during which a decision was made to perform tracheostomy due to expected prolonged re- covery in 3 cases, airway obstruction after extubation due to he- matoma and decreased oxygen saturation in 4 cases. These last 4 tracheostomies were urgently performed under local anesthesia.

None of the patients from the study group died after complications related to postoperative tracheostomy or ET. Six patients out of 120 from the non-ET group had a history of prolonged intubation – extubation was done on the second postoperative day. The first set of analyses examined numbers of patients in the ET and non- ET groups, who would have indications for tracheostomy based on scores obtained in each of 3 scales (Tab. III.). Decisions to perform an ET on the clinical basis resulted in 37% (76/205) ET rate in our practice and 9 out of 129 non-ET patients had postoperative tracheotomy. The ET rate for scale I [16] would be 44% (91/205) and 3 postoperative tracheotomy patients would qualify for ET.

For scale II [17] the ET rate would be 74% (151/205) and 8 out of Tab. II. Analyzed scales criteria.

FACTOR SCORE

SCALE I Major criterion

1. Previously radiated in same region of surgery. 2 2. Resection of two more sub-sites of the oral cavity or

oropharynx. 2

3. Bilateral neck dissection. 2

4. Extended hemi- or central arch mandibulectomy. 2 5. Bulky flap for reconstruction: latissimus dorsi; double skin island pectoralis major myocutaneous flap. 2 6. Flap with a compressing element: intact mandibular rim;

use of a concomitant reconstruction plate. 2 Minor criterion

1. Age > 65 years. 1

2. Previously operated at the same site. 1 3. Trismus (Inter-incisor distance < 1 cm). 1 4. Pathological CT chest findings (COPD, emphysema etc.). 1 SCALE II

Tumour location

Anterior second premolars 1

Posterior second premolars 2

Tumour size T1–T4 1–4

Chest X-ray pathologic findings 1

Multimorbidity 1

Alcohol consumption

No 0

< 100 g alcohol/day 1

> 100 g alcohol/day 2

Hard drinks 3

SCALE III Tumour site

Cutaneous 0

Buccal mucosae 0

Maxilla 0

Mandibular alveolus 1

Anterior tongue 1

Floor of the mouth 2

Soft palate 3

Anterior pillar 3

Tonsillar pillar 4

Posterior tongue 4

Hypopharynx 4

Mandibulectomy 1

Bilateral neck dissection 3

Reconstruction

None 0

RFFF 2

Other 3

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the sensitivity of 61% and specificity of 81%. The scales selected for comparisons used 22 factors as predictors of a need for ET.

Scale I included 10 factors and we used 9 of them in our study, scale II – 6 and we used 5 and scale III – 6 (item 1 was subdivided into 3 items based on tumor location). We analyzed associations between these factors and tracheotomy in the study group. Tab.

IV. lists 8 out of these 22 factors that had significant association with tracheostomy performed in our ET and postoperative tracheotomy patients, and their strength. Previous radiation therapy in the same region, age, previous surgery at the same site, trismus, abnormal chest CT, pulmonary disease, liver disease, extended hemi- or central mandibulectomy, tumor site had insignificant association strength.

DISCUSSION

There is no „gold standard” for making decisions on ET and our analysis cannot indicate which scale is the most appropriate or reliable one. The differences in the interobserver reliability scores among the scales confirm that a retrospective analysis also suffers from a potential bias in assignment of patients to ET or non-ET groups. Publication by Gupta et al. [16] illustrates problems with establishing a scale supporting the decisions on whether to perform ET. The scoring system developed by these authors relied on a retrospective analysis of their clinical practice and thus cap- tured the components that were used in a non-structured man- ner, to make clinical decisions. In their prospective study group these authors also made decisions to perform tracheostomy on 9 postoperative tracheotomy patients would qualify for ET. For

scale III [12] these values would be 73% (150/205) and 8 respectively. The analysis of our ET group shows that according to scale I ET could be safely avoided in 21 cases. For scale II it would be 4 cases and for scale III, 5 cases. In the non-ET group 33 patients who had no ET and did not require postoperative tracheotomy would have indications for ET according to scale I. According to scales II and III ET would be indicated in 71 non-ET, non-postoperative tracheotomy patients.

The agreement between first and second author scoring decisions in the 3rd scale was poor. Fleiss Kappa was 0.29. The decision to perform ET would have been identical in each of the scales in 87 patients. Only 53 of 76 patients who had ET would have indications for ET in each scale. For patients in the postoperative tracheotomy subgroup, in whom the clinical judgement indicated no need for ET, agreement among the scales was also poor. Three of 9 postoperative tracheotomy patients would have indications for ET in each scale. Scale II and III would each establish indications for 8 out of these 9 patients but a total number of ETs would be twice the number based on clinical judgement. Since there is no

„gold standard” for making decisions on ET, the sensitivity and specificity of each scale have a very limited practical value and should be interpreted only as indicators of variability among these scales. The sensitivity of scales I, II and III to detect the clinical decision on ET was 72%, 95% and 93% respectively. The specificity was low – 72% for scale I and 39% for scale II and III. The evaluation of the sensitivity of clinical decisions to detect unanimous qualifications to perform ET with the use of 3 scales resulted in

Tab. III. Number of patients in each group who would have ET based on clinical judgement and scales I–III.

Patients with indications for ET

Indications based on ET study group (n = 76) Non-ET study group (n = 129) Total number of ET PT subgroup (n = 9)

Clinical judgement (study group) 76/76 0/129 76/205 0/0

Scale I [16] 55/76 36/129 91/205 3/9

Scale II [17] 72/76 79/129 151/205 8/9

Scale III [12] 71/76 79/129 150/205 8/9

Tab. IV. Associations between clinical factors and tracheostomy.

Clinical factor Scale χ² df P Association strength*

Resection of two more sub-sites of the oral cavity or

oropharynx I 40.7 1 0.001 .45

Bilateral neck dissection I, III 15 1 0.001 .27

Bulky flap for reconstruction: latissimus dorsi;

double skin island pectoralis major myocutaneous flap

I 40.8 1 0.001 .45

Flap with a compressing element: intact mandibular rim; use of a concomitant reconstruction plate

I 9.3 1 0.002 .21

Tumor size II 26 3 0.001 .36

Multimorbidity II 7.3 1 0.007 .19

Tumor location anteriorly or posteriorly to the

premolar teeth II 14.6 2 0.001 .27

Reconstruction (none vs RFFF vs other) III 40.4 2 0.001 .44

* N = 205. Association strength is measured as phi coefficient for two by two tables, and Cramer’s V for variables with more categories

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Decision to perform ET would be the same according to each scale in 70% of patients in our ET group, while decision not to perform ET would be the same in each scale in 26% of our non-ET group.

Each scale included factors that have a good association strength with our clinical practice decisions but in view of a high variability of decisions it is not possible to make any recommendation regarding an „optimal” combination of these factors. Obesity, bilateral neck dissection, pulmonary disorders [19], cardiovascular disorders [20] were also considered indications for ET. Scales II and III have relatively high sensitivity and their application in our patients would allow to achieve a very low PT rate (only 1 patient would have PT in our group) but their specificity is very low and twice as many patients would undergo ET. Authors of scale II had 25% overall PT rate which indicates that with proper organiza- tion of services indications for ET may be limited and a proper balance between ETs and PTs might depend on local practice and conditions. Application of scale I would result in decisions similar to those made in the study group. Total amount of PTs in our material was similar [17] or lower to that reported by other authors [12]. Prospective study based on decisions made exclusively according to any scale seems to be unacceptable. Some patients who do not qualify for ET on any scale basis will need ET on the clinical basis. Multicenter observational study based on standard decision making and taking into account multiple factors used in the published scales would provide an opportunity to identify a set of the most useful criteria. The major obstacle will be the lack of a “gold standard”. It is not possible to indicate how many ETs should be done or PTs would be acceptable. Available data from the literature show that despite the proposed various criteria for ET qualification, PT is always needed [6, 12, 14, 16, 17].

CONCLUSION

Our retrospective study indicates that application of 3 published scales to a group of patients who were supposed to undergo ET on the clinical basis would result in high variability of decisions.

An „optimal” scale supporting ET decisions should allow to re- duce both ET and PT rates on the basis of a set of predictive clinical factors. There is a wide range of indications for ET depen- ding on the qualification criteria, and thus this could be a good reason for further prospective studies.

„conventional grounds”. The scale established on the earlier clinical practice basis proved to be a reliable predictor of tracheostomy in a prospective group of patients treated by the same team.

Only 0.7% of prospective group patients who had no indications for tracheostomy according to the scale, had to undergo tracheostomy. The rate of postoperative tracheostomy was 7% (9/129) in our patients but we had no patient in whom we would have to change the preoperative decisions, while Gupta et al. made the decisions on tracheostomy during the procedure. As many as 3.1%

had indications for tracheostomy based on the scale but it was jud- ged clinically unnecessary and was not done. These results show a very good consistency of clinical judgements over 11 years but do not indicate how useful the scale would be to establish indications for ET before surgery. The scale proposed by Kruse-Loesler et al.

[17] is based on an experience with 152 patients who had no ET and had a flap reconstruction. In this group 38 (25%) patients had PT (postoperative tracheostomy), more often (44%) in the radial forearm flap subgroup. Retrospective analysis of clinical data was used to find significant parameters and to establish a scoring system supporting the decision making. The authors found a set of 6 variables that would predict tracheostomy with 96.7% accuracy.

Since the decision to perform tracheostomy in patients included in the study was made on the clinical basis during and after surgery, the actual predictive value of this scale in clinical practice would need to be evaluated in a prospective study. It would be intere- sting to know what would be its predictive value in 104 patients who had ET (41% ET rate, similar to our 38%) and were treated by the authors during the same period. Cameron et al. [12] published a scale based on experience with major 148 procedures for head and neck cancer. In 41 procedures ET was done; the non-ET group was subdivided into immediate extubation (52 procedures) or an overnight endotracheal tube ventilation and then extubation (55). Eight (15%) out of 55 patients in the overnight ventilation group required postoperative tracheostomy. The scoring system based on 4 parameters was applied retrospectively and would predict a need for tracheostomy in 2% of immediately extubated patients, 35% of patients ventilated overnight and 90% of patients who had ET. Scoring for patients who had PT is not provided.

This scale is also based on a retrospective search for associations with the clinical course and as such can only confirm the clinical practice adopted by the authors. Our results suggest that the consistency of decisions based on each of the 3 scales would be limited.

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Maciej Rysz PhD; Head and Neck Cancer Department, National Institute of Oncology in Warsaw; Roentgena street 5, 02-791 Warsaw, Poland; Phone: +48 226295283; E-mail: riisz@wp.pl

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