Técnicas de control de calidad en cirugía. Aplicación de las gráficas de control cumulative sum

Comprehensive Learning Curve Analysis of a Long-Term Experience With Thoracic Endovascular Aneurysm Repair

PURPOSE

To analyze the learning curve for thoracic endovascular aortic repair (TEVAR) in a single center over a period of 25 years.

MATERIALS AND METHODS

In total, 390 consecutive standard TEVAR procedures undertaken between 1996 and 2021 were included in a retrospective, observational, single-center study. Cumulative sum charts were elaborated for the entire center experience (primary outcome) as well as for the first and second implanting physicians. Data on procedural variables (contrast volume, operative and fluoroscopy time), 30-day major adverse events (MAEs) and clinical success, and endoleak and reintervention rates were secondary outcomes and subdivided into 4 quartiles of experience (Q1-Q4) or presented as first 2 versus latest 2 quartiles (Q1-Q2 vs Q3-Q4).

RESULTS

The mean follow-up was 4.3±4.0 years. The center's learning curve was achieved after 75 procedures, and it was similar for the first implanting physician. The surgeon coming thereafter had a significantly shorter curve (10 TEVARs). Comparing Q1-Q2 with Q3-Q4, 30-day MAEs (16.1 vs 11.3%, p=0.164), 30-day mortality (11.4% vs 3.6%, p=0.003), and intraoperative additional maneuvers (21.5% vs 13.3%, p=0.033) were reduced along with an improvement in clinical success (85.9% vs 90.3%, p=0.190). From Q1 to Q4, operative time (139.8±65.5 to 76.7±43.7 min, p=0.001), fluoroscopy time (15.1±8.8 to 7.1±5.1 min, p<0.001), and contrast volume (244.0±112.1 to 104.3±46.1 mL, p<0.001) showed a considerable reduction. Late endoleak and aortic-related mortality declined significantly from Q1-Q2 to Q3-Q4 (24.1% to 15.5%, p=0.033 and 18.6% vs 8.2%, p=0.006, respectively). Operative time (p=0.021), contrast volume (p=0.016), and fluoroscopy time (p=0.004) were independent risk factors for endoleak, causing a 1.3-fold risk increase for both each 60 minutes of additional operative time (p=0.021) and every 100 mL of additional contrast medium (p=0.016). Each 10-minute increase in fluoroscopy time determined a 1.4-fold risk increment (p=0.004).

CONCLUSION

The learning curve shortened significantly over time with non-negligible clinical outcome improvements, suggesting that specific endovascular training is mandatory to become an effective TEVAR performer.

CLINICAL IMPACT

For the first time in literature, the standard TEVAR's learning curve has been evaluated at a single vascular surgery center over a period of 25 years. The learning curve for the center and the first physician historically undertaking TEVAR was achieved at the 75th treated patient. The learning curve of the surgeons coming thereafter was significantly shorter (10 cases). This quarter-century demonstrated that intraoperative learning-related variables were associated with long-term clinical outcomes and all have improved over time. Centers approaching TEVAR for the first time and training program providers could use these data to aim to offer better clinical outcomes.

Learning Curve and Long-Term Outcomes of Thoracic Endovascular Repair With the Relay Stent-Graft

PURPOSE

To define the learning curve of a widely employed stent-graft for thoracic endovascular repair (TEVAR) by analyzing procedural variables and their impact on long-term outcomes.

MATERIALS AND METHODS

Standard TEVARs for each major aortic thoracic disease were included excluding procedures using thoracoabdominal, arch fenestrated/branched devices and/or chimneys. The primary outcome was the learning curve analysis using the cumulative sum chart method. The secondary outcomes, presented as early (Q1-Q2) versus latest (Q3-Q4) quartiles of experience, were 30-day major adverse events (MAEs); procedural details (additional maneuvers, operative and fluoroscopy time, and contrast volume); 30-day clinical success; endoleak; aorta-related reintervention; and overall and aorta-related survival.

RESULTS

Between November 2005 and September 2021, 220 consecutive TEVAR procedures involving the Relay endograft (Terumo Aortic, Sunrise, FL, USA) were performed and included in the present analysis. The mean follow-up was 4.5 ± 3.9 years. The learning curve was reached after 10 patients. Secondary outcomes improved significantly over experience. Thirty-day MAE occurrence was 14.5% versus 11.8% (p=0.550). Additional maneuvers (p=0.009), access-vessel additional maneuvers (p=0.010), operative time (p=0.004), Relay Plus (p=0.001), and implantation of multiple stent-grafts (p=0.034) were independent risk markers for MAEs. Operative time (125.9 ± 66.7 vs 86.7 ± 48.5 minutes, p<0.001), contrast volume (185.4 ± 112.8 vs 140.5 ± 88.2 mL, p=0.003), and fluoroscopy time (12.4 ± 12.7 vs 8.8 ± 7.5 minutes, p=0.017) decreased significantly. Late endoleak occurrence was 19.5% with a nonsignificant reduction (21.8% vs 17.3%, p=0.395). Fluoroscopy time (hazard ratio [HR]=1.0; 95% confidence interval [CI]=1.0-1.1; p=0.008), contrast volume (HR=1.0; 95% CI=1.0-1.1; p=0.018), and type III aortic arch (HR=3.3; 95% CI=1.7-6.4; p<0.001) were independent risk markers for endoleak. Fluoroscopy time (HR=1.0; 95% CI=1.0-1.1; p=0.032) and type III aortic arch (HR=3.6; 95% CI=1.7-7.4; p=0.001) confirmed their significant association in a multivariable analysis.

CONCLUSION

In a high-volume center with a consistent previous endovascular experience, the Relay graft presented satisfactory long-term results with a short learning curve supporting its reliability.

CLINICAL IMPACT

The manuscript addresses the understanding of how many TEVAR procedures with a currently implanted device have been required to reach the learning curve for an endovascular skilled center. Our TEVAR experience with the Relay stent-graft (Terumo Aortic) demonstrated that ten implantations were required to achieve the device-related learning curve. The fifteen-year analyzed period showed that intraoperative learning-related variables were associated with long-term clinical outcomes and both improved over time. The Relay stent-graft presented satisfactory long-term results along with a short learning curve in a high-volume endovascular center supporting its ongoing implantation.

Transoral endoscopic thyroidectomy vestibular approach: Results after 53 first cases

INTRODUCTION

Trans Oral Endoscopic Thyroidectomy through Vestibular Approach (TOETVA) allows access to the thyroid with the best cosmetic results as there are no visible scars.

METHODS

Here we present a prospective observational study of 53 patients which underwent TOETVA from July 2017 to June 2021.

RESULTS

Fifty-two cases (98.1%) cases were women (median age 44 years old). Thyroid nodule was the main surgical indication accounting 73.6% of cases. We performed 42 lobectomies and 11 total thyroidectomies; 4 left Central Neck Dissection (CND) were also associated. The median surgical time for port placement was 14 min and for lobectomy, total thyroidectomy and left CND were 80, 140 and 30 min, respectively. The median of hospital stay was 2 days. Dysphonia was present in 4 patients; however, laryngoscopy only confirmed laryngeal nerve impairment in 2 cases, one of them classified as permanent (1.6%). In those patients that underwent total thyroidectomy, the rate of transient hypoparathyroidism was 18.2% whereas permanent was 0%. Regarding complications associated to the new approach, transient chin numbness appeared in all patients with a variable degree of intensity.

CONCLUSTIONS

Transoral surgery is a recent approach in our Unit. Our results, based on the first 53 patients, show that it is a safe and effective approach when performed in appropriately selected patients offering the best cosmetic result. Besides, new complications associated to the approach has been shown to be transient.

Robotic anatomical lung resections: Analysis of the learning curve

INTRODUCTION

Robotic surgery has become a safe and effective approach for the treatment of pulmonary surgical pathology. However, the adoption of new surgical techniques requires the evaluation of the learning curve. The objective of this study is to analyze the learning curve of robotic anatomical lung resections.

METHODS

Retrospective analysis of all robotic anatomical lung resections performed by the same surgeon between June 2018 and March 2020. The learning curve was evaluated using CUSUM charts to estimate trend changes in surgical time, surgical failure and the occurrence of post-operative cardiorespiratory complications throughout the sequence of cases.

RESULTS

The study included a total of 73 cases. The median duration of all complications was 120 min (interquartile range: 90-150 min), the prevalence of surgical failure was 23.29%, while 4/73 patients had any postoperative cardiorespiratory complication. Based on the CUSUM analysis, the learning curve was divided into 3 different phases: phase i (from the first to the 14th intervention), phase ii (between the 15th and 30th intervention) and phase iii (from the 31st intervention).

CONCLUSIONS

The learning curve for robotic anatomical lung resections can be divided into 3 phases. The technical competence that guarantees satisfactory perioperative outcomes was achived in phase iii from the 31st intervention.

Bronchoscopist's perception of the quality of the single-use bronchoscope (Ambu aScope4™) in selected bronchoscopies: a multicenter study in 21 Spanish pulmonology services

BACKGROUND

The disposable bronchoscope is an excellent alternative to face the problem of SARS-CoV-2 and other cross infections, but the bronchoscopist's perception of its quality has not been evaluated.

METHODS

To evaluate the quality of the Ambu-aScope4 disposable bronchoscope, we carried out a cross-sectional study in 21 Spanish pulmonology services. We use a standardized questionnaire completed by the bronchoscopists at the end of each bronchoscopy. The variables were described with absolute and relative frequencies, measures of central tendency and dispersion depending on their nature. The existence of learning curves was evaluated by CUSUM analysis.

RESULTS

The most frequent indications in 300 included bronchoscopies was bronchial aspiration in 69.3% and the median duration of these was 9.1 min. The route of entry was nasal in 47.2% and oral in 34.1%. The average score for ease of use, image, and aspiration quality was 80/100. All the planned techniques were performed in 94.9% and the bronchoscopist was satisfied in 96.6% of the bronchoscopies. They highlighted the portability and immediacy of the aScope4TM to start the procedure in 99.3%, the possibility of taking and storing images in 99.3%. The CUSUM analysis showed average scores > 70/100 from the first procedure and from the 9th procedure more than 80% of the scores exceeded the 80/100 score.

CONCLUSIONS

The aScope4™ scored well for ease of use, imaging, and aspiration. We found a learning curve with excellent scores from the 9th procedure. Bronchoscopists highlighted its portability, immediacy of use and the possibility of taking and storing images.

Robotic anatomical lung resections: Analysis of the learning curve

INTRODUCTION

Robotic surgery has become a safe and effective approach for the treatment of pulmonary surgical pathology. However, the adoption of new surgical techniques requires the evaluation of the learning curve. The objective of this study is to analyze the learning curve of robotic anatomical lung resections.

METHODS

Retrospective analysis of all robotic anatomical lung resections performed by the same surgeon between June 2018 and March 2020. The learning curve was evaluated using CUSUM charts to estimate trend changes in surgical time, surgical failure and the occurrence of post-operative cardiorespiratory complications throughout the sequence of cases.

RESULTS

The study included a total of 73 cases. The median duration of all complications was 120min (interquartile range: 90-150min), the prevalence of surgical failure was 23.29%, while 4/73 patients had any postoperative cardiorespiratory complication. Based on the CUSUM analysis, the learning curve was divided into 3 different phases: phase i (from the first to the 14th intervention), phase ii (between the 15th and 30th intervention) and phase iii (from the 31st intervention).

CONCLUSIONS

The learning curve for robotic anatomical lung resections can be divided into 3 phases. The technical competence that guarantees satisfactory perioperative outcomes was achived in phase iii from the 31st intervention.

Including non-concurrent control patients in the analysis of platform trials: is it worth it?

BACKGROUND

Platform trials allow adding new experimental treatments to an on-going trial. This feature is attractive to practitioners due to improved efficiency. Nevertheless, the operating characteristics of a trial that adds arms have not been well-studied. One controversy is whether just the concurrent control data (i.e. of patients who are recruited after a new arm is added) should be used in the analysis of the newly added treatment(s), or all control data (i.e. non-concurrent and concurrent).

METHODS

We investigate the benefits and drawbacks of using non-concurrent control data within a two-stage setting. We perform simulation studies to explore the impact of a linear and a step trend on the inference of the trial. We compare several analysis approaches when one includes all the control data or only concurrent control data in the analysis of the newly added treatment.

RESULTS

When there is a positive trend and all the control data are used, the marginal power of rejecting the corresponding hypothesis and the type one error rate can be higher than the nominal value. A model-based approach adjusting for a stage effect is equivalent to using concurrent control data; an adjustment with a linear term may not guarantee valid inference when there is a non-linear trend.

CONCLUSIONS

If strict error rate control is required then non-concurrent control data should not be used; otherwise it may be beneficial if the trend is sufficiently small. On the other hand, the root mean squared error of the estimated treatment effect can be improved through using non-concurrent control data.

Cumulative sum analysis of the learning curve for the preclosure technique using Proglide

OBJECTIVES

Our study aims to assess the technical quality and the learning curve of the preclosure technique for a vascular surgeon using Proglide using cumulative sum analysis (CUSUM analysis).

METHODS

This study was designed retrospectively and enrolled 81 consecutive patients with 88 access sites who underwent endovascular aortic repair or thoracic endovascular aortic repair with the preclosure technique using Proglide between July 2017 and February 2018. The patients were divided into 2 groups chronologically: (A) the first 40 cases and (B) the latter 41 cases. Logistic regression analysis was used to assess the impact of technical risk factors on the success of the preclosure technique, and the χ2 test and 1-way ANOVA were applied to analyse the distribution of individual characteristics and risk factors between the 2 groups. CUSUM analysis was adapted to analyse the learning curve and to monitor the technical quality, with a predetermined target failure rate of 5%, an alternative failure rate of 20% and calculated 80% 'alert', 95% 'alarm' and 80% 'reassurance' lines.

RESULTS

Primary technical success was obtained in 81 (92.05%) access sites. There were no significant correlations between primary technical success and risk factors, including, common femoral artery diameter (P = 0.88), common femoral artery depth from the skin (P =0.94), the level of common femoral artery calcification (P =0.86) and size of sheath (P =0.96). Moreover, the distribution of related risk factors was not significantly different between groups A and B. CUSUM analysis showed that the cumulative failure rate never crossed the 80% 'alert' and 95% 'alarm' lines. Additionally, the failure rate began to approach the 80% 'reassurance' line after ∼22 cases and crossed the 80% 'reassurance' line after 36 cases.

CONCLUSIONS

The technique of totally percutaneous access using Proglide is safe and effective for an experienced vascular surgeon, even if the operator has no previous experience with any preclosure techniques. CUSUM analysis showed that 36 cases are necessary to achieve the target failure rate of 5%.