The Laryngoscope C 2014 The American Laryngological, V
Rhinological and Otological Society, Inc.
Transoral Robotic Surgery in Benign Diseases Including Obstructive Sleep Apnea: Safety and Feasibility Paul T. Hoff, MS, MD; Mark A. D’Agostino, MD; Erica R. Thaler, MD Objectives/Hypothesis: To evaluate the safety and feasibility of the da Vinci Surgical System in transoral roboticassisted surgery for benign indications. Study Design: A multicenter, single-arm, retrospective case series. Methods: Perioperative outcomes were recorded for patients presenting with obstructive sleep apnea, airway obstruction, lingual tonsillar/tonsillar/tongue base hypertrophy, or dysphagia who underwent one or more transoral procedures, including lingual tonsillectomy and tongue base resection (partial glossectomy) at one of three US institutions. Results: Between January 2010 and October 2013, 285 patients (age 51.5 years, body mass index 30.5 kg/m2) underwent 293 procedures. No conversions or blood transfusions were needed. The average operative time was 86.7 minutes, and the average volume of tissue resected (lingual tonsil and tongue base) was 8.3 mL. Hospital stays averaged 1.8 days, and the postoperative complication rate was 20.7%. There were no complications specifically related to the use the da Vinci Surgical System, and none of the complications were life threatening. Conclusions: These results demonstrate that it is safe and feasible to use the da Vinci Surgical System to perform lingual tonsillectomy and base of tongue resection (partial glossectomy) procedures for benign indications. Key Words: Obstructive sleep apnea, transoral robotic surgery, dysphagia, hypertrophy, tonsillar, glossectomy, lingual. Level of Evidence: 4 Laryngoscope, 125:1249–1253, 2015
INTRODUCTION In the past 2 decades, the need for minimally invasive techniques for transoral head and neck surgical procedures has grown. Surgeons have explored a variety of minimally invasive techniques for pharyngeal and laryngeal cancer, thyroidectomy, skull base surgery, and obstructive sleep apnea, but the main limitation has been line of sight visualization of the operative field. Surgical retractors and laryngoscopes are typically utilized in conjunction with operating microscopes positioned outside the oral cavity, constraining the surgeon to an operative field that is in line with the microscope. This may translate into the inability to create adequate exposure. Although at times endoscopes may be used, they are almost always handheld, preventing
From the Department of Surgery (P.T.H.), St. Joseph Mercy Health System, Ann Arbor, Michigan; Department of Surgery (M.A.D.), Middlesex Hospital, Middletown, Connecticut; Department of Otorhinolaryngology– Head and Neck Surgery (E.R.T.), University of Pennsylvania, Philadelphia, Pennsylvania, U.S.A. Editor’s Note: This Manuscript was accepted for publication October 12, 2014. This study was supported and funded by Intuitive Surgical, the manufacturer of the da Vinci Surgical System, as partial fulfillment of a regulatory submission to the US Food and Drug Administration for the use of the da Vinci Surgical System in benign TORS indications. Drs. Hoff and D’Agostino are proctors for Intuitive Surgical. The authors have no other funding, financial relationships, or conflicts of interest to disclose. Send correspondence to Paul T. Hoff, MD, 5333 McAuley Drive, Suite 2017, Ann Arbor, MI 48106. E-mail: [email protected] DOI: 10.1002/lary.25026
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the surgeon from performing two-handed maneuvers for diagnosis and treatment. In addition, these endoscopes lack depth perception. Procedures such as a partial glossectomy can be lengthy to complete and may result in edema, which could be avoided by shortening the procedure time (Fujita et al.1 and Chabolle et al.2). Additionally, bleeding can be difficult to control, resulting in an incomplete resection. Robot-assisted technology was investigated as a means to overcome the surgical limitations associated with current techniques. The transoral robotic-assisted surgical approach provides surgeons with improved dexterity and precision, as well as three-dimensional vision and depth perception. O’Malley et al.3 introduced transoral robotic surgery (TORS) for resection of base of tongue neoplasms in 2006. The da Vinci Surgical System (Intuitive Surgical, Inc., Sunnyvale, CA) received US Food & Drug Administration (FDA) clearance for transoral otolaryngology surgical procedures restricted to benign and malignant tumors classified as T1 and T2 on December 16, 2009. In 2011, Vicini et al.4 utilized the TORS approach for the treatment of obstructive sleep apnea (OSA). The da Vinci Surgical System is pending clearance by the FDA for tongue base resection in benign indications. The current study was primarily focused on evaluating the surgeons’ ability to obtain adequate surgical exposure with the da Vinci Surgical System in patients undergoing TORS for nontumor benign indications (such as OSA) without the need for conversion to a nonrobotic approach. The feasibility of the procedure was Hoff et al.: Robotic Surgery for Obstructive Sleep Apnea
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TABLE I. Patient Demographics. Parameter
Data for 293 TORS Procedures
Age, yr Mean (SD) Range [minimum, maximum]
51.5 (11.1) [23, 81]
BMI, kg/m2 Mean (SD) Range [minimum, maximum]
30.5 (4.9)* [17.4, 55.68]
Ethnic origin, N {%} African American Asian Caucasian Hispanic Other/unknown
16 {5.5} 6 {2.1} 253 {86.3} 5 {1.7} 13 {4.4}
Comorbidity, N {%} None 1
69 {23.5} 100 {34.1}
2
62 {21.2}
3 American Society Anesthesiology Classification, N {%} 1
62 {21.2}
5 {1.7}
2
197 {67.2}
3 4
88 {30.0} 1 {0.4}
Unknown Diagnosis, N {%}† Airway obstruction Tissue hypertrophy‡ Obstructive sleep apnea Dysphagia
2 {0.7} 54 {18.4} 18 {6.1} 289 {98.6} 3 {1.0}
*Four missing data points. † The preoperative diagnosis was not mutually exclusive, therefore each patient could have more than one diagnosis. ‡ Tissue hypertrophy included lingual tonsillar/tonsillar/tongue base hypertrophy. BMI 5 body mass index; SD, standard deviation; TORS 5 transoral robotic surgery.
also measured by the surgeons’ ability to resect tissue. The safety of the procedure was measured by the evaluation of intraoperative and postoperative complications.
MATERIALS AND METHODS Deidentified data were collected for all TORS cases performed by one of the three authors at three different US institutions. A subset of these patients were involved in another multicenter study examining different parameters (Vicini et al.5). The surgical techniques used were similar among the three investigators, and followed that described by Vicini et al.4 Approval was obtained from the institutional review board at each individual institution prior to data collection (Saint Joseph Mercy Health System Institutional Review Board, University of Pennsylvania Institutional Review Board, and Middlesex Hospital Institutional Review Board), and this study was registered at Clinicaltrials.gov (NCT02002845). Indications included OSA, airway obstruction, lingual tonsillar/tonsillar/
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tongue base hypertrophy, or dysphagia. Inclusion criteria were benign pathology and 18 years of age at the time of the procedure (a lingual tonsillectomy, base of tongue resection, or a partial glossectomy). Exclusion criteria were tumor and malignant indications (such as oropharyngeal cancer). Data collection included patient age, body mass index (BMI), gender, ethnic origin, type of procedure, cosurgeries performed, length of operative time, length of robotic operating time, use of sealants, volume of tissue resected, the need for tracheostomy, conversion to open cases, length of hospital stay, complications, and readmissions. All complications requiring intervention up to 3 months postoperatively were collected. For each complication, the investigator evaluated the severity of the event, its causal relationship to the procedure performed, its relationship to the device (da Vinci Surgical System), and the patient’s underlying condition. In the case of a complication, the patient’s medical course was followed until resolution, including any additional intervention (surgical or medical) necessary to prevent permanent impairment. Standard univariate and bivariate descriptive statistics were used for data analysis. Discrete data were expressed as proportions of the total. All continuous variables were described using means, standard deviations, and ranges.
RESULTS Between January 1, 2010 and October 31, 2013, a total of 293 TORS procedures were performed in 285 patients. Each of the three sites contributed at least 75 cases. There were eight patients who required revision surgery in order to resect additional tissue. The types of initial and revision surgeries for each patient were similar. The average time period between the two separate procedures was 8.1 months (range, 5–12 months). Patient demographics and preoperative characteristics are specified in Table I, with patients undergoing two procedures counted twice. The average age was 51.5 years, and the average BMI was 30.5 kg/m2. The majority of the patients were male (77.8%), Caucasian (86.3%), had at least one comorbidity (76.5%) (e.g., diabetes, hypertension, smoker), and had a diagnosis of OSA (98.6%). There were 133 (45.4%) patients with a history of prior oral surgery. The 293 procedures performed included lingual tonsillectomy alone or with base of tongue resection (partial glossectomy). Additional nonrobotic and robotic procedures were also conducted, as described in Table II. The most common concomitant nonrobotic procedures were uvulopalatopharyngoplasty (UPPP) (66.2%), lateral pharyngoplasty (12.3%), palatine tonsillectomy (32.1%), and palatal Z-plasty (9.6%). Approximately two-thirds of the palatine tonsillectomies were conducted in conjunction with UPPP procedures. The average overall operative time (including all concomitant procedures) was 86.7 minutes, and the estimated intraoperative blood loss was 27.5 mL. No conversions or blood transfusions were reported. The average volume of tissue resected (lingual tonsil and tongue base) was 8.3 mL. In 73 procedures, the surgeon chose to use a surgical sealant at the conclusion of the procedure. One patient underwent a planned tracheostomy, and the tracheostomy tube was removed 39 days later. Feeding tubes were placed following two procedures, and in both Hoff et al.: Robotic Surgery for Obstructive Sleep Apnea
TABLE II. Intraoperative and Postoperative Results. Parameter
Data for 293 TORS Procedures
Concomitant robotic surgical procedures, N (%) Palatine tonsillectomy
10 (3.4)
Epiglottectomy Epiglottoplasty
27 (9.2) 22 (7.5)
Other procedures*
5 (1.7)
Common concomitant nonrobotic procedures, N (%) UPPP/revisional UPPP
reported a painful feeling of “saliva gathering.” Odynophagia was not documented at the 3-month sleep study, and the patient was subsequently lost to follow-up. As such, no additional information for this patient was available at the time of this report. The symptom (dysphagia or odynophagia) was temporary for the rest of the patients and resolved with medication (primarily pain medication). Of the 59 patients who experienced complications, 28 patients (9.6%) were readmitted after discharge.
194 (66.2)
DISCUSSION
Lateral pharyngoplasty
36 (12.3)
Palatine tonsillectomy Palatal Z-plasty
94 (32.1) 28 (9.6)
This study demonstrates that TORS for non– tumor-based benign indications is a successful surgical approach by the criteria of adequate exposure, feasibility to resect tissue, and safety. With regard to adequate exposure, there were no patients who required conversion to a nonrobotic procedure, and no patients whose procedures were aborted was due to lack of exposure. This is particularly significant given that these patients are typically of higher BMI than previously reported patients undergoing TORS procedures for tumor (Weinstein et al.6). These patients often have some component of macroglossia and retrognathia as well, which may limit exposure to the posterior oropharynx and base of tongue. The surgeons were able to resect an average of 8.3 mL of tissue, which is well within the range of tissue volume deemed necessary to effect change in apnea-hypopnea index (Vicini et al.4). It should be noted that this is an average volume, with an upward range of 36.8 mL seen in this study, a significantly greater tissue volume than these authors have been
Operative time, min Mean [SD] Range {minimum, maximum}
86.7 [36.0]† {23, 246}
Estimated blood loss, mL Mean [SD] Range {minimum, maximum}
27.5 [34.1] {0, 400}
Volume of tissue resection, mL‡ Mean [SD] Range {minimum, maximum}
8.3 [3.7]§ {1.0, 36.8}
Length of stay, d Mean [SD] Range {minimum, maximum}
1.8 [1.3] {1.0, 12.0}
*Other procedures included: supraglottoplasty, epiglottopexy, uvuloplasty, uvulectomy, and endoscopy. † Two missing data points. ‡ Tongue base and lingual tonsil. § Twenty-five missing data points. SD 5 standard deviation; TORS 5 transoral robotic surgery; UPPP 5 uvulopalatopharyngoplasty.
cases, the feeding tubes were removed within 1 day. The average hospital stay was 1.8 days. Fifty-nine (59) patients experienced a total of 77 complications within the 3-month follow-up period (Table III). This included complications related to the TORS procedures as well as any concomitant robotic and nonrobotic procedures conducted during the same operation. There were no complications specifically related to the use the da Vinci Surgical System, and none of the complications were life threatening; all complications were resolved by intervention and/or hospitalization. The most common complications were bleeding, dehydration, and dysphagia requiring intervention. All 12 cases of bleeding were resolved by an intervention such as cauterization. The average onset time for bleeding was 7.3 days (range, 0–18 days). Fourteen patients experienced dehydration requiring intravenous hydration. All dehydration events resolved after treatment with intravenous fluids. Fifteen patients experienced dysphagia/odynophagia postoperatively. The main reason for dysphagia was postoperative pain, which affected food intake. One patient experienced postoperative odynophagia due to pain. At the 2-month follow-up visit, this patient Laryngoscope 125: May 2015
TABLE III. Surgical Complications. Complication Type
No.
Bleeding
12
Dehydration requiring treatment Dysphagia/odynophagia requiring treatment
14 15
Pneumonia
6
Reintubation >6-hour intubation
2 2
Hypoxemia
6
Pain* Gastrointestinal complications
3 1
Cardiac arrhythmias Other† Total
1 15 77‡
*Types of pain included chest pain, throat pain, and unspecified pain. † Other complications included: nausea, deep venous thrombosis, urinary retention, shortness of breath, tongue swelling, atelectasis, aspiration pneumonitis, thrush, encephalopathy, superficial venous thrombophlebitis, fever, possible transient ischemic attack, altered mental status, bronchitis, and orthostatic hypotension. ‡ There were 77 total complications in 59 patients.
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able to remove using nonrobotic techniques (data not shown). Obstruction in the retrolingual space can be due to a number of etiologies, including macroglossia (large muscular tongue), epiglottic prolapse, and lingual tonsil hypertrophy. TORS is suited to address all of these problems with unsurpassed visualization through a 0 or 30 high-definition three-dimensional lens, excellent exposure, and the ability to have a surgical assistant providing a second set of hands for suction and retraction. TORS allows the surgeon to perform complete reduction of the lingual tonsil, as well as additional tissue including the base of tongue musculature and epiglottis. Suturing of a prolapsed epiglottis is also possible with the robotic arms. In addition, the operating time is considerably less (30–90 minutes compared to several hours for nonrobotic surgery). This is critically important for OSA patients, where extra soft tissue edema from prolonged retraction may significantly impede postoperative airway safety. This study demonstrates the safety of the transoral robotic approach. There were no complications directly related to the da Vinci Surgical System in the study, and none of the complications were life threatening. The complication rate was comparable to other large series at 20.7%, and all events resolved without significant clinical sequelae. The most common complications were of comparable incidence to TORS for tumor (Weinstein et al.6). In our study, there were few airway complications after surgery. However, sleep apnea patients are known to have difficult airways, which put them at higher risk. Therefore, patients should have close cardiopulmonary monitoring in an inpatient setting for at least 24 hours following surgery. Patients without significant contraindications should receive perioperative steroids to prevent edema. In this setting, only two patients required reintubation, and almost all patients were successfully extubated immediately in the operating room following the procedure. There are always individual patient factors that may determine a more cautious approach to extubation. One helpful predictor of postoperative airway challenges is the relative ease or difficulty of intubation at the beginning of the procedure. A cautious approach to extubation is prudent if the initial intubation is challenging. Although this series reported no mortalities, practitioners should be mindful that the site of surgery and patient population together make for potential postoperative risks beyond traditional surgery for OSA, such as UPPP alone. The incidence of bleeding in our study (4.1%) was at a level consistent with the literature concerning surgery of the tonsils, palate, and base of tongue (Kezirian et al.7). Patients on anticoagulants and antiplatelet medications (other than low-dose aspirin at 81 mg/d) such as Plavix, should not undergo TORS base of tongue resection unless they can hold their medication for at least 1 month postoperatively and hold their medication preoperatively following standard protocol. In our study, at least two of the postoperative hemorrhages were due to initiation of Plavix or warfarin at the 2-week mark. In one case, this was done for a pulmonary embolus, and Laryngoscope 125: May 2015
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in the other case it was due to the cardiologist’s recommendation given the patient’s history of a prior stent for coronary artery disease. Finally, though there were complaints of dysphagia, only two patients in the study required temporary feeding tubes in the postoperative period. All other patients with odynophagia responded to pain medicine. There are few articles in the literature specifically addressing complication rates and safety issues in surgery for OSA. Comparison of other OSA procedures with TORS is difficult because there are not many truly comparable procedures. However, in reviewing other reports on complications resulting from multilevel surgery for OSA, the TORS approach is comparable in complication rate. Woodson and Fujita8 reported a 27% complication rate in their report on lingualplasty (a modification of midline glossectomy) as part of surgical management of OSA. They reported complications such as bleeding, tongue edema, prolonged odynophagia, and subcutaneous emphysema. Hou et al.9 reported a complication rate of 24% in their article on the treatment of OSA with UPPP and midline glossectomy, including complications of tongue swelling and prolonged intubation, hypoxemia, and wound dehiscence. Kezirian et al. reported a serious complication rate of 1.5% and a mortality rate of 0.2% after UPPP (with or without multilevel surgery) in a large multi-institutional study. However, they only investigated life-threatening complications, and did not report less serious complications such as dehydration and dysphagia as were investigated in our study. Lin et al.10 reported a complication rate of 14.6% in their meta-analysis of the efficacy of multilevel surgery of the upper airway for OSA (specific complications were not mentioned).
CONCLUSION The results from this multicenter, retrospective, nontumor TORS dataset demonstrate a more than reasonable safety and feasibility profile of the da Vinci Surgical System in lingual tonsillectomy/base of tongue resection and partial glossectomy procedures for nontumor benign indications. As with any new technical innovation, TORS for OSA must be undertaken with these potential complications in mind, in a setting where careful and appropriate postoperative monitoring of patients may be reasonably undertaken.
BIBLIOGRAPHY 1. Fujita S, Conway WA, Zorick F, et al. Surgical corrections of anatomical abnormalities in obstructive sleep apnea syndrome: uvulopalatopharyngoplasty. Otolaryngol Head Neck Surg 1981;89:923–934. 2. Chabolle F, Wagner I, Blumen MB, Sequert C, Fleury B, De Dieuleveult T. Tongue base reduction with hyoepiglottoplasty: a treatment for severe obstructive sleep apnea. Laryngoscope 1999;109:1273–1280. 3. O’Malley BW Jr, Weinstein GS, Snyder W, Hockstein NG. Transoral robotic surgery (TORS) for base of tongue neoplasms. Laryngoscope 2006;116:1465–1472. 4. Vicini C, Dallan I, Canzi P, et al. Transoral robotic surgery of the tongue base in obstructive sleep apnea-hypopnea syndrome: anatomic considerations and clinical experience. Head Neck 2012;34:15–22. 5. Vicini C, Montevecchi F, Campanini A, et al. Clinical outcomes and complications associated with TORS for OSAHS: a benchmark for evaluating an emerging surgical technology in a targeted application for benign disease. ORL J Otorhinolaryngol Relat Spec 2014;76:63–69.
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6. Weinstein GS, O’Malley BW Jr, Magnuson JS, et al. Transoral robotic surgery: a multicenter study to assess feasibility, safety, and surgical margins. Laryngoscope 2012;122:1701–1707. 7. Kezirian EJ, Weaver EM, Yueh B, et al. Incidence of serious complications after uvulopalatopharyngoplasty. Laryngoscope 2004;114:450–453. 8. Woodson BT, Fujita S. Clinical experience with lingualplasty as part of the treatment of severe obstructive sleep apnea. Otolaryngol Head Neck Surg 1992;107:40–48.
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9. Hou J, Yan J, Wang B, et al. Treatment of obstructive sleep apneahypopnea syndrome with combined uvulopalatopharyngoplasty and midline glossectomy: outcomes from a 5-year study Respir Care 2012;57: 2104–2110. 10. Lin H, Friedman M, Chang H, Gurpinar B. The efficacy of multilevel surgery of the upper airway in adults with obstructive sleep apnea/hypopnea syndrome. Laryngoscope 2008;118:902–908.
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Rhinological and Otological Society, Inc.
Transoral Robotic Surgery in Benign Diseases Including Obstructive Sleep Apnea: Safety and Feasibility Paul T. Hoff, MS, MD; Mark A. D’Agostino, MD; Erica R. Thaler, MD Objectives/Hypothesis: To evaluate the safety and feasibility of the da Vinci Surgical System in transoral roboticassisted surgery for benign indications. Study Design: A multicenter, single-arm, retrospective case series. Methods: Perioperative outcomes were recorded for patients presenting with obstructive sleep apnea, airway obstruction, lingual tonsillar/tonsillar/tongue base hypertrophy, or dysphagia who underwent one or more transoral procedures, including lingual tonsillectomy and tongue base resection (partial glossectomy) at one of three US institutions. Results: Between January 2010 and October 2013, 285 patients (age 51.5 years, body mass index 30.5 kg/m2) underwent 293 procedures. No conversions or blood transfusions were needed. The average operative time was 86.7 minutes, and the average volume of tissue resected (lingual tonsil and tongue base) was 8.3 mL. Hospital stays averaged 1.8 days, and the postoperative complication rate was 20.7%. There were no complications specifically related to the use the da Vinci Surgical System, and none of the complications were life threatening. Conclusions: These results demonstrate that it is safe and feasible to use the da Vinci Surgical System to perform lingual tonsillectomy and base of tongue resection (partial glossectomy) procedures for benign indications. Key Words: Obstructive sleep apnea, transoral robotic surgery, dysphagia, hypertrophy, tonsillar, glossectomy, lingual. Level of Evidence: 4 Laryngoscope, 125:1249–1253, 2015
INTRODUCTION In the past 2 decades, the need for minimally invasive techniques for transoral head and neck surgical procedures has grown. Surgeons have explored a variety of minimally invasive techniques for pharyngeal and laryngeal cancer, thyroidectomy, skull base surgery, and obstructive sleep apnea, but the main limitation has been line of sight visualization of the operative field. Surgical retractors and laryngoscopes are typically utilized in conjunction with operating microscopes positioned outside the oral cavity, constraining the surgeon to an operative field that is in line with the microscope. This may translate into the inability to create adequate exposure. Although at times endoscopes may be used, they are almost always handheld, preventing
From the Department of Surgery (P.T.H.), St. Joseph Mercy Health System, Ann Arbor, Michigan; Department of Surgery (M.A.D.), Middlesex Hospital, Middletown, Connecticut; Department of Otorhinolaryngology– Head and Neck Surgery (E.R.T.), University of Pennsylvania, Philadelphia, Pennsylvania, U.S.A. Editor’s Note: This Manuscript was accepted for publication October 12, 2014. This study was supported and funded by Intuitive Surgical, the manufacturer of the da Vinci Surgical System, as partial fulfillment of a regulatory submission to the US Food and Drug Administration for the use of the da Vinci Surgical System in benign TORS indications. Drs. Hoff and D’Agostino are proctors for Intuitive Surgical. The authors have no other funding, financial relationships, or conflicts of interest to disclose. Send correspondence to Paul T. Hoff, MD, 5333 McAuley Drive, Suite 2017, Ann Arbor, MI 48106. E-mail: [email protected] DOI: 10.1002/lary.25026
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the surgeon from performing two-handed maneuvers for diagnosis and treatment. In addition, these endoscopes lack depth perception. Procedures such as a partial glossectomy can be lengthy to complete and may result in edema, which could be avoided by shortening the procedure time (Fujita et al.1 and Chabolle et al.2). Additionally, bleeding can be difficult to control, resulting in an incomplete resection. Robot-assisted technology was investigated as a means to overcome the surgical limitations associated with current techniques. The transoral robotic-assisted surgical approach provides surgeons with improved dexterity and precision, as well as three-dimensional vision and depth perception. O’Malley et al.3 introduced transoral robotic surgery (TORS) for resection of base of tongue neoplasms in 2006. The da Vinci Surgical System (Intuitive Surgical, Inc., Sunnyvale, CA) received US Food & Drug Administration (FDA) clearance for transoral otolaryngology surgical procedures restricted to benign and malignant tumors classified as T1 and T2 on December 16, 2009. In 2011, Vicini et al.4 utilized the TORS approach for the treatment of obstructive sleep apnea (OSA). The da Vinci Surgical System is pending clearance by the FDA for tongue base resection in benign indications. The current study was primarily focused on evaluating the surgeons’ ability to obtain adequate surgical exposure with the da Vinci Surgical System in patients undergoing TORS for nontumor benign indications (such as OSA) without the need for conversion to a nonrobotic approach. The feasibility of the procedure was Hoff et al.: Robotic Surgery for Obstructive Sleep Apnea
1249
TABLE I. Patient Demographics. Parameter
Data for 293 TORS Procedures
Age, yr Mean (SD) Range [minimum, maximum]
51.5 (11.1) [23, 81]
BMI, kg/m2 Mean (SD) Range [minimum, maximum]
30.5 (4.9)* [17.4, 55.68]
Ethnic origin, N {%} African American Asian Caucasian Hispanic Other/unknown
16 {5.5} 6 {2.1} 253 {86.3} 5 {1.7} 13 {4.4}
Comorbidity, N {%} None 1
69 {23.5} 100 {34.1}
2
62 {21.2}
3 American Society Anesthesiology Classification, N {%} 1
62 {21.2}
5 {1.7}
2
197 {67.2}
3 4
88 {30.0} 1 {0.4}
Unknown Diagnosis, N {%}† Airway obstruction Tissue hypertrophy‡ Obstructive sleep apnea Dysphagia
2 {0.7} 54 {18.4} 18 {6.1} 289 {98.6} 3 {1.0}
*Four missing data points. † The preoperative diagnosis was not mutually exclusive, therefore each patient could have more than one diagnosis. ‡ Tissue hypertrophy included lingual tonsillar/tonsillar/tongue base hypertrophy. BMI 5 body mass index; SD, standard deviation; TORS 5 transoral robotic surgery.
also measured by the surgeons’ ability to resect tissue. The safety of the procedure was measured by the evaluation of intraoperative and postoperative complications.
MATERIALS AND METHODS Deidentified data were collected for all TORS cases performed by one of the three authors at three different US institutions. A subset of these patients were involved in another multicenter study examining different parameters (Vicini et al.5). The surgical techniques used were similar among the three investigators, and followed that described by Vicini et al.4 Approval was obtained from the institutional review board at each individual institution prior to data collection (Saint Joseph Mercy Health System Institutional Review Board, University of Pennsylvania Institutional Review Board, and Middlesex Hospital Institutional Review Board), and this study was registered at Clinicaltrials.gov (NCT02002845). Indications included OSA, airway obstruction, lingual tonsillar/tonsillar/
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tongue base hypertrophy, or dysphagia. Inclusion criteria were benign pathology and 18 years of age at the time of the procedure (a lingual tonsillectomy, base of tongue resection, or a partial glossectomy). Exclusion criteria were tumor and malignant indications (such as oropharyngeal cancer). Data collection included patient age, body mass index (BMI), gender, ethnic origin, type of procedure, cosurgeries performed, length of operative time, length of robotic operating time, use of sealants, volume of tissue resected, the need for tracheostomy, conversion to open cases, length of hospital stay, complications, and readmissions. All complications requiring intervention up to 3 months postoperatively were collected. For each complication, the investigator evaluated the severity of the event, its causal relationship to the procedure performed, its relationship to the device (da Vinci Surgical System), and the patient’s underlying condition. In the case of a complication, the patient’s medical course was followed until resolution, including any additional intervention (surgical or medical) necessary to prevent permanent impairment. Standard univariate and bivariate descriptive statistics were used for data analysis. Discrete data were expressed as proportions of the total. All continuous variables were described using means, standard deviations, and ranges.
RESULTS Between January 1, 2010 and October 31, 2013, a total of 293 TORS procedures were performed in 285 patients. Each of the three sites contributed at least 75 cases. There were eight patients who required revision surgery in order to resect additional tissue. The types of initial and revision surgeries for each patient were similar. The average time period between the two separate procedures was 8.1 months (range, 5–12 months). Patient demographics and preoperative characteristics are specified in Table I, with patients undergoing two procedures counted twice. The average age was 51.5 years, and the average BMI was 30.5 kg/m2. The majority of the patients were male (77.8%), Caucasian (86.3%), had at least one comorbidity (76.5%) (e.g., diabetes, hypertension, smoker), and had a diagnosis of OSA (98.6%). There were 133 (45.4%) patients with a history of prior oral surgery. The 293 procedures performed included lingual tonsillectomy alone or with base of tongue resection (partial glossectomy). Additional nonrobotic and robotic procedures were also conducted, as described in Table II. The most common concomitant nonrobotic procedures were uvulopalatopharyngoplasty (UPPP) (66.2%), lateral pharyngoplasty (12.3%), palatine tonsillectomy (32.1%), and palatal Z-plasty (9.6%). Approximately two-thirds of the palatine tonsillectomies were conducted in conjunction with UPPP procedures. The average overall operative time (including all concomitant procedures) was 86.7 minutes, and the estimated intraoperative blood loss was 27.5 mL. No conversions or blood transfusions were reported. The average volume of tissue resected (lingual tonsil and tongue base) was 8.3 mL. In 73 procedures, the surgeon chose to use a surgical sealant at the conclusion of the procedure. One patient underwent a planned tracheostomy, and the tracheostomy tube was removed 39 days later. Feeding tubes were placed following two procedures, and in both Hoff et al.: Robotic Surgery for Obstructive Sleep Apnea
TABLE II. Intraoperative and Postoperative Results. Parameter
Data for 293 TORS Procedures
Concomitant robotic surgical procedures, N (%) Palatine tonsillectomy
10 (3.4)
Epiglottectomy Epiglottoplasty
27 (9.2) 22 (7.5)
Other procedures*
5 (1.7)
Common concomitant nonrobotic procedures, N (%) UPPP/revisional UPPP
reported a painful feeling of “saliva gathering.” Odynophagia was not documented at the 3-month sleep study, and the patient was subsequently lost to follow-up. As such, no additional information for this patient was available at the time of this report. The symptom (dysphagia or odynophagia) was temporary for the rest of the patients and resolved with medication (primarily pain medication). Of the 59 patients who experienced complications, 28 patients (9.6%) were readmitted after discharge.
194 (66.2)
DISCUSSION
Lateral pharyngoplasty
36 (12.3)
Palatine tonsillectomy Palatal Z-plasty
94 (32.1) 28 (9.6)
This study demonstrates that TORS for non– tumor-based benign indications is a successful surgical approach by the criteria of adequate exposure, feasibility to resect tissue, and safety. With regard to adequate exposure, there were no patients who required conversion to a nonrobotic procedure, and no patients whose procedures were aborted was due to lack of exposure. This is particularly significant given that these patients are typically of higher BMI than previously reported patients undergoing TORS procedures for tumor (Weinstein et al.6). These patients often have some component of macroglossia and retrognathia as well, which may limit exposure to the posterior oropharynx and base of tongue. The surgeons were able to resect an average of 8.3 mL of tissue, which is well within the range of tissue volume deemed necessary to effect change in apnea-hypopnea index (Vicini et al.4). It should be noted that this is an average volume, with an upward range of 36.8 mL seen in this study, a significantly greater tissue volume than these authors have been
Operative time, min Mean [SD] Range {minimum, maximum}
86.7 [36.0]† {23, 246}
Estimated blood loss, mL Mean [SD] Range {minimum, maximum}
27.5 [34.1] {0, 400}
Volume of tissue resection, mL‡ Mean [SD] Range {minimum, maximum}
8.3 [3.7]§ {1.0, 36.8}
Length of stay, d Mean [SD] Range {minimum, maximum}
1.8 [1.3] {1.0, 12.0}
*Other procedures included: supraglottoplasty, epiglottopexy, uvuloplasty, uvulectomy, and endoscopy. † Two missing data points. ‡ Tongue base and lingual tonsil. § Twenty-five missing data points. SD 5 standard deviation; TORS 5 transoral robotic surgery; UPPP 5 uvulopalatopharyngoplasty.
cases, the feeding tubes were removed within 1 day. The average hospital stay was 1.8 days. Fifty-nine (59) patients experienced a total of 77 complications within the 3-month follow-up period (Table III). This included complications related to the TORS procedures as well as any concomitant robotic and nonrobotic procedures conducted during the same operation. There were no complications specifically related to the use the da Vinci Surgical System, and none of the complications were life threatening; all complications were resolved by intervention and/or hospitalization. The most common complications were bleeding, dehydration, and dysphagia requiring intervention. All 12 cases of bleeding were resolved by an intervention such as cauterization. The average onset time for bleeding was 7.3 days (range, 0–18 days). Fourteen patients experienced dehydration requiring intravenous hydration. All dehydration events resolved after treatment with intravenous fluids. Fifteen patients experienced dysphagia/odynophagia postoperatively. The main reason for dysphagia was postoperative pain, which affected food intake. One patient experienced postoperative odynophagia due to pain. At the 2-month follow-up visit, this patient Laryngoscope 125: May 2015
TABLE III. Surgical Complications. Complication Type
No.
Bleeding
12
Dehydration requiring treatment Dysphagia/odynophagia requiring treatment
14 15
Pneumonia
6
Reintubation >6-hour intubation
2 2
Hypoxemia
6
Pain* Gastrointestinal complications
3 1
Cardiac arrhythmias Other† Total
1 15 77‡
*Types of pain included chest pain, throat pain, and unspecified pain. † Other complications included: nausea, deep venous thrombosis, urinary retention, shortness of breath, tongue swelling, atelectasis, aspiration pneumonitis, thrush, encephalopathy, superficial venous thrombophlebitis, fever, possible transient ischemic attack, altered mental status, bronchitis, and orthostatic hypotension. ‡ There were 77 total complications in 59 patients.
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able to remove using nonrobotic techniques (data not shown). Obstruction in the retrolingual space can be due to a number of etiologies, including macroglossia (large muscular tongue), epiglottic prolapse, and lingual tonsil hypertrophy. TORS is suited to address all of these problems with unsurpassed visualization through a 0 or 30 high-definition three-dimensional lens, excellent exposure, and the ability to have a surgical assistant providing a second set of hands for suction and retraction. TORS allows the surgeon to perform complete reduction of the lingual tonsil, as well as additional tissue including the base of tongue musculature and epiglottis. Suturing of a prolapsed epiglottis is also possible with the robotic arms. In addition, the operating time is considerably less (30–90 minutes compared to several hours for nonrobotic surgery). This is critically important for OSA patients, where extra soft tissue edema from prolonged retraction may significantly impede postoperative airway safety. This study demonstrates the safety of the transoral robotic approach. There were no complications directly related to the da Vinci Surgical System in the study, and none of the complications were life threatening. The complication rate was comparable to other large series at 20.7%, and all events resolved without significant clinical sequelae. The most common complications were of comparable incidence to TORS for tumor (Weinstein et al.6). In our study, there were few airway complications after surgery. However, sleep apnea patients are known to have difficult airways, which put them at higher risk. Therefore, patients should have close cardiopulmonary monitoring in an inpatient setting for at least 24 hours following surgery. Patients without significant contraindications should receive perioperative steroids to prevent edema. In this setting, only two patients required reintubation, and almost all patients were successfully extubated immediately in the operating room following the procedure. There are always individual patient factors that may determine a more cautious approach to extubation. One helpful predictor of postoperative airway challenges is the relative ease or difficulty of intubation at the beginning of the procedure. A cautious approach to extubation is prudent if the initial intubation is challenging. Although this series reported no mortalities, practitioners should be mindful that the site of surgery and patient population together make for potential postoperative risks beyond traditional surgery for OSA, such as UPPP alone. The incidence of bleeding in our study (4.1%) was at a level consistent with the literature concerning surgery of the tonsils, palate, and base of tongue (Kezirian et al.7). Patients on anticoagulants and antiplatelet medications (other than low-dose aspirin at 81 mg/d) such as Plavix, should not undergo TORS base of tongue resection unless they can hold their medication for at least 1 month postoperatively and hold their medication preoperatively following standard protocol. In our study, at least two of the postoperative hemorrhages were due to initiation of Plavix or warfarin at the 2-week mark. In one case, this was done for a pulmonary embolus, and Laryngoscope 125: May 2015
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in the other case it was due to the cardiologist’s recommendation given the patient’s history of a prior stent for coronary artery disease. Finally, though there were complaints of dysphagia, only two patients in the study required temporary feeding tubes in the postoperative period. All other patients with odynophagia responded to pain medicine. There are few articles in the literature specifically addressing complication rates and safety issues in surgery for OSA. Comparison of other OSA procedures with TORS is difficult because there are not many truly comparable procedures. However, in reviewing other reports on complications resulting from multilevel surgery for OSA, the TORS approach is comparable in complication rate. Woodson and Fujita8 reported a 27% complication rate in their report on lingualplasty (a modification of midline glossectomy) as part of surgical management of OSA. They reported complications such as bleeding, tongue edema, prolonged odynophagia, and subcutaneous emphysema. Hou et al.9 reported a complication rate of 24% in their article on the treatment of OSA with UPPP and midline glossectomy, including complications of tongue swelling and prolonged intubation, hypoxemia, and wound dehiscence. Kezirian et al. reported a serious complication rate of 1.5% and a mortality rate of 0.2% after UPPP (with or without multilevel surgery) in a large multi-institutional study. However, they only investigated life-threatening complications, and did not report less serious complications such as dehydration and dysphagia as were investigated in our study. Lin et al.10 reported a complication rate of 14.6% in their meta-analysis of the efficacy of multilevel surgery of the upper airway for OSA (specific complications were not mentioned).
CONCLUSION The results from this multicenter, retrospective, nontumor TORS dataset demonstrate a more than reasonable safety and feasibility profile of the da Vinci Surgical System in lingual tonsillectomy/base of tongue resection and partial glossectomy procedures for nontumor benign indications. As with any new technical innovation, TORS for OSA must be undertaken with these potential complications in mind, in a setting where careful and appropriate postoperative monitoring of patients may be reasonably undertaken.
BIBLIOGRAPHY 1. Fujita S, Conway WA, Zorick F, et al. Surgical corrections of anatomical abnormalities in obstructive sleep apnea syndrome: uvulopalatopharyngoplasty. Otolaryngol Head Neck Surg 1981;89:923–934. 2. Chabolle F, Wagner I, Blumen MB, Sequert C, Fleury B, De Dieuleveult T. Tongue base reduction with hyoepiglottoplasty: a treatment for severe obstructive sleep apnea. Laryngoscope 1999;109:1273–1280. 3. O’Malley BW Jr, Weinstein GS, Snyder W, Hockstein NG. Transoral robotic surgery (TORS) for base of tongue neoplasms. Laryngoscope 2006;116:1465–1472. 4. Vicini C, Dallan I, Canzi P, et al. Transoral robotic surgery of the tongue base in obstructive sleep apnea-hypopnea syndrome: anatomic considerations and clinical experience. Head Neck 2012;34:15–22. 5. Vicini C, Montevecchi F, Campanini A, et al. Clinical outcomes and complications associated with TORS for OSAHS: a benchmark for evaluating an emerging surgical technology in a targeted application for benign disease. ORL J Otorhinolaryngol Relat Spec 2014;76:63–69.
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6. Weinstein GS, O’Malley BW Jr, Magnuson JS, et al. Transoral robotic surgery: a multicenter study to assess feasibility, safety, and surgical margins. Laryngoscope 2012;122:1701–1707. 7. Kezirian EJ, Weaver EM, Yueh B, et al. Incidence of serious complications after uvulopalatopharyngoplasty. Laryngoscope 2004;114:450–453. 8. Woodson BT, Fujita S. Clinical experience with lingualplasty as part of the treatment of severe obstructive sleep apnea. Otolaryngol Head Neck Surg 1992;107:40–48.
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9. Hou J, Yan J, Wang B, et al. Treatment of obstructive sleep apneahypopnea syndrome with combined uvulopalatopharyngoplasty and midline glossectomy: outcomes from a 5-year study Respir Care 2012;57: 2104–2110. 10. Lin H, Friedman M, Chang H, Gurpinar B. The efficacy of multilevel surgery of the upper airway in adults with obstructive sleep apnea/hypopnea syndrome. Laryngoscope 2008;118:902–908.
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