Effect of 2 Teams and Operative Time on Complications After Oral Cavity Free Flap Reconstruction

Abstract

Objective:

Evaluate the effects of operative time and 2 team approach on complications after soft tissue free flap reconstruction for oral tongue cancer.

Methods:

Patients with oncologic glossectomy with myocutaneous or fasciocutaneous free flap reconstruction were included from the 2015 to 2018 American College of Surgery National Surgical Quality Improvement Program. The primary predictive variables assessed were operative time and 2 team approach; control variables included age, sex, body mass index (BMI), 5-question-modified frailty index (mFI-5), American Society of Anesthesiologists (ASA) class, and total work relative value units (wRVU). Outcomes assessed included 30-day mortality, 30-day reoperation, hospital length of stay beyond 30 days, readmission, medical and surgical complications, and non-home discharge. Multivariable logistic/linear regression models were used to predict surgical outcomes.

Results:

Microvascular soft tissue free flap reconstruction of the oral cavity after glossectomy was performed on 839 patients. Operative time was independently associated with readmission, prolonged length of stay, surgical complications, medical complications, and non-home discharge. A 2-team approach was independently associated with prolonged length of stay and medical complications. The mean operative time of the 1-team and 2-team approach was 8.73 and 9.13 hours. The 1-team approach did not significantly increase operative time (P = .16).

Conclusions:

In the largest study to date of operative time on post-surgical outcomes after glossectomy and soft tissue free flap reconstruction, we found longer operative times increased rates of postoperative complications and non-home discharge. The 1-team approach is non-inferior to the 2-team approach with respect to operating time and complications.

Keywords

operative time complications 2-team teamwork efficiency free flap

Introduction

An increase in head and neck cancers, combined with pioneering approaches to resect more advanced disease, has demanded the need for sophisticated reconstructive surgeries. One such technique, microvascular free tissue transfer, involves transferring autologous tissue from one site on the body to another with an intact arterial and venous system. The usage of microvascular free tissue transfer in head and neck surgeries is becoming the preferred method in head and neck cancer reconstruction due to better functional and cosmetic outcomes, in addition to a high overall success rate of up to 97%.¹

Although free flap reconstruction has numerous benefits, it comes with complications, due to the increased morbidity and operative time inherent in flap harvest and anastomosis.^2,3 Additionally, vascular compromise may result in longer intensive care unit (ICU) and hospital stays, more surgical interventions, and poor functional outcomes.⁴ Variables that have previously been implicated in post-operative complications after free flap reconstruction include the patient’s acute or chronic coexisting conditions, the extent of the surgery, multidisciplinary perioperative care, and operative time.⁵ Head and neck flap reconstruction has a mean operating time of about 7 hours and a range between 3 and 12 hours.^6,7 Previous studies using the American College of Surgery (ACS) National Surgical Quality Improvement Program (NSQIP) database has shown increased operative time to be associated with higher rates of medical and surgical complications.^2,8
-10 However, these studies have focused on reconstruction of the upper aerodigestive tract as a whole, with a large variety of defects reconstructed and varying rates of complications. The goal of this study is to try to standardize the outcomes by focusing on myocutaneous or fasciocutaneous free flap reconstruction after glossectomy alone to better elucidate the role operative time has on clinical outcomes.

Additionally, the authors have chosen to assess the impact of a 1- or 2-team surgical approach on operative time in these complex cases. The use of the 2-team model for head and neck reconstruction, with a separate ablative and reconstructive team, has become prevalent in most high volume institutions.¹¹ The use of 2 teams intuitively should decrease the surgical time by allowing simultaneous harvest of soft tissue or bony flaps during oncologic resection. In this study, the authors attempt to assess the effect the 2-team approach has on operative time at a national level using the NSQIP database.

Materials and Methods

This was a cross-sectional study utilizing the ACS NSQIP database and was determined exempt by the Institutional Review Board (IRB), as deidentified secondary data were used for analysis. The ACS NSQIP contains surgical data and 30-day risk adjusted surgical outcomes from over 600 hospitals.¹² NSQIP data were queried from 2015 to 2018 for cases of oral cavity extirpation with free tissue transfer utilized for reconstruction. Cases with an oncologic glossectomy and soft tissue (myocutaneous or fasciocutaneous) free flap reconstruction during a single anesthetic event by either 1 or 2 teams were included. The excision and reconstruction common procedural terminology (CPT) codes are detailed in Supplemental Appendix Table 1. There are 21 CPT code variables within the ACS NSQIP: Principal CPT, Other CPT 1-10, Concurrent CPT 1-10. The Principal CPT and Other CPT variables are procedures performed by the primary surgical team and the Concurrent CPT variables are procedures performed by a separate surgical team. Two types of cases were included: (Case 1: [excision code as the Principal CPT OR Other CPT] AND [reconstruction code as the Concurrent CPT]) and (Case 2: [reconstruction code as the Principal CPT OR Other CPT] AND [excision code as the Concurrent CPT]). Additionally, cases were excluded if reconstruction and oncologic resection were performed by the same team: (Case 1: reconstruction AND excision codes as the Principal CPT OR Other CPT) and (Case 2: reconstruction AND excision codes as the Concurrent CPT), see Supplemental Appendix Table 2. Cases were divided into a 1- and 2-team approach based on the presence of concurrent team CPT codes. Cases with an ASA class of 5 (moribund) and with missing predictive and outcome variables were excluded. Additionally, cases with operative time under 3 hours were excluded, as these were determined to be highly unlikely and not supported by ranges of surgery reported in literature.^6,13,14 Additionally, cases with operative times was 1.5× the interquartile range (IQR) lesser or greater than the 25th or 75th percentile respectively were designated as outliers and removed. Flowchart of data processing is presented in Figure 1. Given the sample size of the project, only clinically relevant variables were included in the final models: age, sex, American Society of Anesthesiologist (ASA) class, a calculated 5-question-modified frailty index (mFI-5),¹⁵ body mass index (BMI), total work relative value units (wRVU),¹⁶ preoperative comorbidities, and operative time, see Supplemental Appendix Table 1. Additional variables, such as tumor stage, would have been included but are not available within the NSQIP database. Total wRVU was calculated to attempt control of case complexity given this data limitation. Differences in demographic variables and operative time across 1- and 2-team surgery was performed using t tests for continuous variables and chi-square test for categorical variables, see Table 1.

Table 1.

Demographic Data by Team Approach.

Variable	One team^a	Two team^b	Total	P value
Patient number	375 (100%)	464 (100%)	839 (100%)
Operative time, h^c	8.73 ± 2.54	9.13 ± 2.64	8.95 ± 2.6	<.01
Age, y^c	60.42 ± 12.49	59.96 ± 12.34	60.17 ± 12.4	<.01
18-40	26 (6.93%)	33 (7.11%)	59 (7.03%)
41-60	156 (41.6%)	207 (44.61%)	363 (43.27%)
61-80	173 (46.13%)	204 (43.97%)	377 (44.93%)
>80	20 (5.33%)	20 (4.31%)	40 (4.77%)
Gender				.17
Male	231 (61.6%)	308 (66.38%)	539 (64.24%)
Female	144 (38.4%)	156 (33.62%)	300 (35.76%)
BMI,^c kg/m²	26.4 ± 6.36	25.81 ± 6.36	26.08 ± 6.36	<.01
Underweight (≤18.5)	29 (7.73%)	38 (8.19%)	67 (7.99%)
Normal (18.5-24.99)	147 (39.2%)	202 (43.53%)	349 (41.6%)
Overweight (25-29.99)	108 (28.8%)	123 (26.51%)	231 (27.53%)
Obese (≥30)	91 (24.27%)	101 (21.77%)	192 (22.88%)
ASA Classification				.03
Class 1: No Disturbance	1 (0.27%)	2 (0.43%)	3 (0.36%)
Class 2: Mild Disturbance	88 (23.47%)	78 (16.81%)	166 (19.79%)
Class 3: Severe Disturbance	269 (71.73%)	346 (74.57%)	615 (73.3%)
Class 4: Life Threatening	17 (4.53%)	38 (8.19%)	55 (6.56%)
modified Frailty Index-5 (mFI-5)^c	0.63 ± 0.75	0.67 ± 0.73	0.65 ± 0.74	<.01
0	194 (51.73%)	222 (47.84%)	416 (49.58%)
1	132 (35.2%)	179 (38.58%)	311 (37.07%)
≥2	44 (11.73%)	59 (12.72%)	103 (12.28%)
Preoperative comorbidities
Diabetes	43 (11.47%)	57 (12.28%)	100 (11.92%)	.80
Smoker	138 (36.8%)	182 (39.22%)	320 (38.14%)	.52

Abbreviations: ASA, American Society of Anesthesiologists; BMI, body mass index; CHF, congestive heart failure; COPD, chronic obstructive pulmonary disease; FOM, floor of mouth.

Percentages in parenthesis represent the fraction of patients with a 1-team approach.

Percentages in parenthesis represent the fraction of patients with a 2-team approach.

Continuous variables are described with the mean ± standard deviation.

Outcomes, modeled separately, included 30-day mortality, 30-day reoperation, hospital length of stay beyond 30 days, readmission, medical and surgical complications, and non-home discharge. The primary predictive variables assessed for associations with each outcome were operative time and 2-team approach. All models controlled for a set of secondary variables which included age, sex, body mass index (BMI), ASA class, mFI-5, and total wRVU. ASA class and a calculated mFI-5 were used as markers of patient’s pre-operative health status.¹⁵ Total wRVU was used as a marker of case complexity.¹⁶ wRVU calculations were based on the NSQIP-reported measurements and no secondary discounting of codes was performed for subsequent procedures in a single operation.

All analyses were conducted using SAS software version 9.4 (SAS Institute Inc) and the R statistical computing environment.¹⁷ Outcomes were modeled separately to assess for associations with each of the primary predictor variables while controlling for all secondary variables. Odds ratios (OR) and 95% confidence intervals (CI) were obtained by exponentiating logistic regression coefficients. Then a multivariable linear regression model assessing for the association between operative time and the use of a 2-team approach while controlling for the secondary variables was estimated. A P-value <.5 was considered a significant result for the analysis.

Results

After considering all exclusion criteria, 839 cases of microvascular soft tissue free flap reconstruction after oncologic glossectomy were abstracted. The mean operative time for the cohort was 8.95 ± 2.6 hours (range: 3.17-15.80). Within 30 days of surgery, there were 297 complications and 4 mortalities. Most patients had multiple co-morbidities with an ASA class 3 or higher (79.86%) and smoking rates of 38.14%. An ASA class of 4 or more was present in 8.19% (38 patients) of the 2-team cohort compared to only 4.53% (17 patients) of the 1-team cohort. Additionally, the mFI-5 was significantly higher with 2-team approach (mean 0.63 ± 0.75) compared to 1-team approach (mean 0.67 ± 0.67). Further demographic data are presented in Table 1.

Multivariable logistic regression models assessing operative time and the outcomes of interest are presented in Table 2. After controlling for other significant predictors, such as case complexity (wRVU) and patient frailty (ASA and mFI-5), logistic regression models found that operative time (hours) was an independent predictor of prolonged length of stay (OR: 1.12; 95% CI: 1.05-1.21), surgical complications (OR: 1.13; 95% CI: 1.06-1.20), medical complications (OR: 1.09; 95% CI: 1-1.18), and non-home discharge (OR: 1.09; 95% CI: 1.01-1.18).

Table 2.

Multivariable Logistic Regression Models Assessing Free Flap Outcomes in Relation to Operative Time (hours).

Complication	Operative time OR (95% CI)	P value
Death within 30 d	1.04 (0.67-1.57)	.86
Length of stay ≥30 d	1.12 (1.05-1.21)	<.01
Readmission within 30 d	1.21 (1-1.46)	.05
Reoperation within 30 d	1.02 (0.91-1.14)	.68
Surgical complications	1.13 (1.06-1.2)	<.01
Medical complications	1.09 (1-1.18)	.04
Non-home discharge	1.09 (1.01-1.18)	.03

Note. Control variables included: age, sex, body mass index (BMI), 5-question-modified frailty index (mFI-5), American Society of Anesthesiologists (ASA) class, and total work relative value units (wRVU). Odds ratio and P value for control variables are not listed.

Abbreviations: CI, confidence interval; OR, odds ratio.

Of the 839 included cases, 375 (44.70%) patients underwent glossectomy and soft tissue free flap reconstruction with 1 team, and 464 (55.30%) patients underwent resection and reconstruction with 2 separate teams. The mean operative time for the 1-team and 2-team approach was 8.73 and 9.13 hours respectively, see Figure 2. Multivariable linear regression models showed a non-significant 0.24 hour (95% CI: −0.09 to 0.57) increase in operative time linked to the 2-team approach (P = .16), see Table 3.

Table 3.

Multivariable Linear Regression Assessing Variables Impacting Operative Time.

Variables	Coefficients OR (95% CI)	P value
Two teams	0.24 (−0.09 to 0.57)	.16
Frailty	0.11 (−0.14 to 0.35)	.40
ASA^a	0.03 (−1.89 to 1.95)	.97
BMI	0 (−0.03 to 0.02)	.75
Sex	0.59 (0.25-0.94)	<.01
Age	−0.02 (−0.04 to −0.01)	<.01
wRVU	0.03 (0.02-0.03)	<.01

Abbreviations: ASA, American Society of Anesthesiologists; BMI, body mass index; mFI-5, 5-question modified frailty index; wRVU, work relative value units.

Linear approximation used for ordered categorical variable.

Finally, a multivariable logistic regression model was performed comparing outcomes in the 2-team versus 1-team approach. This model shows that the 2-team approach was associated with higher rates of prolonged length of stay (OR: 1.69; 95% CI: 1.18-2.45) and medical complications (OR: 2.01; 95% CI: 1.33-3.08), independent of frailty and case complexity (wRVU), see Table 4.

Table 4.

Multivariable Logistic Regression Models Assessing Free Flap Outcomes in Relation to the 1 Team Versus 2 Team.

Complication	Two team OR (95% CI)	P value
Death within 30 days	1.94 (0.21-43.33)	.59
Length of stay ≥30 days	1.69 (1.18-2.45)	<.01
Readmission within 30 days	1.22 (0.44-3.71)	.71
Reoperation within 30 days	1.27 (0.74-2.22)	.38
Surgical complications	1.27 (0.92-1.75)	.15
Medical complications	2.01 (1.33-3.08)	<.01
Non-home discharge	0.7 (0.47-1.03)	.07

Abbreviations: CI, confidence interval; OR, odds ratio.

Note. Control independent variables included: age, sex, body mass index (BMI), 5-question-modified frailty index (mFI-5), American Society of Anesthesiologists (ASA) class, and total work relative value units (wRVU). Odds ratio and P value for control variables are not listed.

Discussion

Increased operative time in microvascular reconstruction has consistently been linked to more complications and worse outcomes. Ligh et al¹⁸ identified a 17% rate of reoperation during the perioperative period, with inciting causes including prolonged operative time, graft failure, and postoperative complications. In a study by Daley et al⁸ shorter operative time resulted in fewer UTIs, surgical infections, pneumonia, and prolonged intubation. Offodile et al² identified a dose-dependent relationship between operative time and flap failure. In their study, an operation lasting between 6 and 12 hours compared to less than 6 hours had greater than 4-fold increased odds of flap failure. Similarly, Singh et al⁹ documented that 31.4% of the 200 patients who required a microvascular free tissue transfer for head and neck cancer developed complications when the operative time was greater than 10 hours. In our study, we further demonstrated increased operative time was an independent predictor of prolonged length of stay and multiple post-surgical complications. Unexpectedly, we found that a 1-team operative approach was non-inferior to the 2-team approach with respect to operative time and complications, with a difference in mean operative time of 24 minutes. This additionally demonstrates the potential room for improving 2-team efficiency at the national level.

The 2-team approach should fundamentally lead to faster operative times and, therefore, better outcomes. The theoretical benefits of a 2-team approach include simultaneous surgery, shorter operative time, single-goal focus for the surgeon, and fatigue prevention.^19
-21 Yet, this large dataset from the ACS NSQUIP database demonstrates that, on a national level in the United States, a 1-surgeon approach may result in similar operative times and post-surgical outcomes compared to that of a 2-surgeon approach. The reason for this discrepancy is unclear with the availability of the data in the NSQIP database. A common impression is that 2-team approaches are used in more complex cases that require more time and can result in high rates of complications. Indeed, in this analysis, there was a higher proportion of patients with elevated ASA class, both class 3 (severe disturbance) and class 4 (life threatening disturbance), in the 2-team approach. Additionally, patients within the 2-team cohort had a significantly higher mean frailty, represented with the mFI-5. These findings corroborate a generalized higher patient medical complexity level with 2-team approaches. In our model, we attempted to control for case complexity by focusing only on glossectomy and soft tissue reconstruction cases only and weighting cases based on total wRVU. After controlling for these factors, patients who underwent 1-team surgery had non-inferior operative times and clinical outcomes.

Despite these findings, other factors, including simultaneous versus serial harvest of the flap reconstruction donor site, are not available within the NSQIP database for analysis and may influence the operative times and related complications with a 2-team approach. Classically, surgical extirpation is performed by one surgical team followed by reconstruction performed by another team. The reconstruction is tailored to fit the defect after obtaining negative surgical margins, and the harvest of the donor tissue often starts after extirpation is completed. However, there has been a recent trend toward more simultaneous extirpation and harvest of the donor site tissue to reduce operative times and increase surgical efficiency. This may allow for decreased operative time without any significantly increased rate of complications or compromise on surgical margins.²² Given the consistent data showing worse surgical outcomes with increased operative times, more emphasis should be placed on simultaneous extirpation and harvest to maximize surgical efficiency and improve outcomes.

Due to their complexity and long average operative time, microvascular reconstructions offer ample opportunities to increased surgical efficiency. These cases have multiple phases, including pre-incision, extirpation and harvest, microvascular anastomosis, inset, and closure. In an observational study of operative efficiency in free flap reconstruction, Bahethi et al²³ identified about 20% of operative time was spent during the pre-incision process. Additionally, multiple room entries and exits occurred due to lack of preoperative communication about supply needs and surgical setup. This resulted in an average pre-incisional process of 1.6 hours after induction.²³ These inefficiencies have been shown to improve with experience and surgical team familiarity that result in significant reductions in overall operative time.²⁴ Focus should be placed on improving consistency of approach and operative efficiency to better surgical outcomes.

This study is limited due to the use of a retrospective database with no controls, and it focuses interpretation on a large database with limited ability to interpret the data for individual cases. The NSQIP does not provide TNM staging characteristics, which does limit a more sophisticated view of case complexity. However, total wRVU has been demonstrated to correlate well with case complexity in multiple surgical specialties.^16,25,26 Additionally, the mFI-5 has been validated as a tool in predicting complications after free flap reconstruction.²⁷ We uniquely utilized a combination of these factors in an attempt to control for operative complexity and patient preoperative health. There are many institutional practices, such as the participation of advanced trainees, including head and neck fellows, which may not be accounted for when considering operative time in 1-team surgery. These fellows may fall under the classification of the primary team for purposes of ACS NSQIP database documentation yet may be functioning as a simultaneously operating reconstruction team. This, of course, may reduce operative time in cases classified as 1-team. The NSQIP additionally does not allow differentiation between cases performed with simultaneous and subsequent free flap harvest with 2 teams. Finally, timings of anesthesia, pre-incision preparation time, patient transport and transfer timing, and location of postoperative care may vary between institutions and between cases, and the database is limited in being able to account for this.

Conclusion

To our knowledge, this study is the largest assessment of operative time on free flap outcomes in head and neck reconstruction of the oral cavity. We found the 1-team approach had non-inferior operative time and post-surgical complications at a national level. The data is limited by its retrospective nature and lack of detail on individual cases. Further research into the efficient utilization of the 2-team surgical approach for microvascular reconstruction is warranted possible to reduce operative times and improve surgical outcomes.

Supplemental Material

sj-docx-1-aor-10.1177_00034894231164802 – Supplemental material for Effect of 2 Teams and Operative Time on Complications After Oral Cavity Free Flap Reconstruction

Supplemental material, sj-docx-1-aor-10.1177_00034894231164802 for Effect of 2 Teams and Operative Time on Complications After Oral Cavity Free Flap Reconstruction by Noah Shaikh, Kinza Noor, Haseeb Jafary, Jeffson Chung, Tanya Fancy and William Stokes in Annals of Otology, Rhinology & Laryngology

Footnotes

Acknowledgements

The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) and the hospitals participating in the ACS-NSQIP were the source of the data used. They have not verified and are not responsible for the statistical validity of the data analysis or the conclusions we have derived.

Authors’ Note

Presentation: This manuscript was presented as an oral presentation at the American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) Annual Meeting on October 6th, 2021.

Author Contributions

Noah Shaikh, MD: study design, acquisition of data, data analysis and interpretation, manuscript drafting, critical revision. Kinza Noor, BS: data analysis, manuscript drafting. Haseeb Jafary, BA: data analysis, manuscript drafting. Jeffson Chung, MD: data analysis and interpretation, critical revision. Tanya Fancy, MD: data analysis and interpretation, critical revision. William Stokes, MD: study design, acquisition of data, data analysis and interpretation, manuscript drafting, critical revision.

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

Data Availability

Database material is publicly available and analytic code is available on request.

ORCID iDs

Noah Shaikh

William Stokes

Supplemental Material

Supplemental material for this article is available online.

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