Carbon dioxide embolism during transanal total mesorectal excision (taTME)

Detection of carbon dioxide embolism by transesophageal echocardiography during transanal/perineal endoscopic surgery: a pilot study

The transanal/perineal (ta/tp) endoscopic approach has been widely used for anorectal surgery in recent years, but carbon dioxide embolism is a possible lethal complication. The frequency of this complication in this approach is not known. In this study, we investigated the frequency of intraoperative (including occult) carbon dioxide embolism using transesophageal echocardiography. Patients who underwent surgery via the ta/tp approach and consented to participate were included. Intraoperative transesophageal echocardiography was used to observe the right ventricular system in a four-chamber view. Changes in end-tidal carbon dioxide (EtCO₂), oxygen saturation (SpO₂), and blood pressure were taken from anesthesia records. Median maximum insufflation pressure during the ta/tp approach was 13.5 (12-18) mmHg. One patient (4.8%) was observed to have a bubble in the right atrium on intraoperative transesophageal echocardiography, with a decrease in EtCO₂ from 39 to 35 mmHg but no obvious change in SpO₂ or blood pressure. By lowering the insufflation pressure from 15 to 10 mmHg and controlling bleeding from the veins around the prostate, the gas rapidly disappeared and the operation could be continued. Among all patients, the range of variation in intraoperative EtCO₂ was 5-22 mmHg, and an intraoperative decrease in EtCO₂ of > 3 mmHg within 5 min was observed in 19 patients (median 5 mmHg in 1-10 times).Clinicians should be aware of carbon dioxide embolism as a rare but potentially lethal complication of anorectal surgery, especially when using the ta/tp approach.

Efficacy of transperineal minimally invasive surgery with laparoscopic abdominoperineal excision for lower rectal cancer

PURPOSE

In abdominoperineal excision (APE), the advantages of the "down-to-up" approach are expected to be more obvious when performed as a two-team approach, including transperineal minimally invasive surgery (TpMIS). We investigated the efficacy of TpMIS with laparoscopic APE for lower rectal cancer.

METHODS

Patients who underwent laparoscopic APE with (n = 20) or without (n = 30) TpMIS between December 2013 and April 2020 were retrospectively reviewed. Patient and tumor characteristics, intraoperative outcome, short-term outcome, and pathological findings were compared. Additional subgroup analyses were performed in technically challenging cases, including male patients, obese patients, and patients with tumors located at the anterior wall.

RESULTS

There was no marked difference in the patient or tumor characteristics or short-term outcomes, including morbidity and mortality between the two groups. Pathological results were comparable, and the circumferential resection margin (CRM) positive rate was 10% in both groups. TpMIS achieved a significant reduction in operative time (p = 0.02). In a subgroup analysis, the amount of blood loss was also smaller in males (p = 0.02) and patients with a high BMI (> 25) (p = 0.005) than in others.

CONCLUSION

Simultaneously performing TpMIS and laparoscopic APE is feasible owing to the favorable complication and CRM-positive rates. In terms of operative time and blood loss, TpMIS is expected to be advantageous in both easy and challenging cases.

Carbon Dioxide Embolism During Transanal Total Mesorectal Excision: Case Report and Literature Review

The actual incidence of carbon dioxide embolism during transanal total mesorectal excision (taTME) is unknown, but the reported incidence in the existing literature is reassuring. However, the incidence of CO2 embolism, which can be life-threatening, is severely underestimated. By reviewing the available data on carbon dioxide embolism during taTME and synthesizing other reports on CO2 embolism in laparoscopic procedures, we provide the first comprehensive account of the etiology, pathophysiology, and recommend tools to monitor carbon dioxide embolism during taTME. Additionally, we provide guidance and recommendations on preventive and therapeutic measures to minimize the adverse consequences of this potentially severe complication, knowledge about which we hope will improve patients' safety.

Limitations and Concerns with Transanal Total Mesorectal Excision for Rectal Cancer

Transanal total mesorectal excision (TaTME) was developed to overcome the technical challenges of a minimally invasive (ultra-) low anterior resection. This new technique has recently come under careful scrutiny as technical pitfalls were reported, in specific relation to the transanal approach. Patients are at risk for urologic lesions. Moreover, carbon dioxide embolism is a rare but potentially life-threatening complication. The benefit of TaTME from an oncological point of view has neither been clarified. Hypothetically, better visualization of the lower rectum could lead to better dissection and total mesorectal excision (TME) specimens, resulting in better oncologic results. Up until now, retrospective multicenter reports seem to show that short-term oncologic results are not inferior after TaTME as compared with after laparoscopic TME. Alarming reports have however been published from Norway suggesting a high incidence and particular multifocal pattern of early local recurrence. In this article, a balanced overview is given of the most important technical pitfalls and oncological concerns arising with this new procedure.

Defining the learning curve of transanal total mesorectal excision: a systematic review and meta-analysis

BACKGROUND

Transanal total mesorectal excision (taTME) represents a novel approach to rectal dissection. Although many structured training programs have been developed worldwide to assist surgeons in implementing this new technique, the learning curve (LC) of taTME has yet to be conclusively defined. This is particularly important given the concerns regarding the complication profile and oncological safety of taTME. The aim of this review was to provide an up-to-date systematic review and meta-analysis of the LC for taTME, comparing the difference of outcomes between the LC and after learning curve (ALC) groups.

METHODS

An up-to-date systematic review was performed on the available literature between 2010-2020 on PubMed, EMBASE, Medline and Cochrane Library databases. All studies comparing taTME procedures before and after LC were analysed.

RESULTS

Seven retrospective studies of prospectively collected databases were included, comparing 333 (51.0%) patients in the LC group and 320 (49.0%) patients in the ALC group. There was a significantly reduced number of adverse intra-operative events, anastomotic leaks and improved quality of mesorectal excision in the ALC group.

CONCLUSION

This review shows that there is a significant improvement in clinical outcomes between the LC and ALC groups which supports the need for careful mastery and ongoing technical refinement during the LC in taTME. This procedure should be performed on a subset of carefully selected patients in the hands of experienced and well-trained teams dedicated to ongoing audit.

Venous Gas Embolism During Radical Robotic Prostatectomy: A Case Report and Evidence-Based Management Algorithm

Robotic-assisted radical prostatectomy (RARP) has gained rapid popularity in the last two decades after early reports of excellent survival rates, quick learning curves, and minimal invasion or tissue damage. Given the anatomical location of surgical prostatectomies and the utilization of intra-abdominal gas during laparoscopy, there is a risk of developing venous air embolism (VAE). We present a case of a 62-year-old male with hypothyroidism and benign prostatic hyperplasia who underwent robotic suprapubic prostatectomy under general anesthesia. One hour after incision the ETCO2 suddenly dropped (40 mmHg to 25 mmHg) as did the SpO2 (98% to 90%). There were no other vital sign changes, nor was there significant blood loss. The surgical team was notified, which prompted the surgeon to inform us that he had just been dissecting around the pelvic venous plexus. At this point, with the clinical suspicion of VAE, abdominal insufflation pressure was lowered, and inspired oxygen was increased to 100%. After 10 minutes, SpO2 and ETCO2 normalized. A debrief and literature review inspired us to develop a laparoscopic-specific VAE management algorithm, with attention to robotic-case management issues. To the best of our knowledge, this is a rare case report describing a clinical VAE during RARP.

Transanal Total Mesorectal Excision in Mid-Low Rectal Cancer: Evaluation of the Learning Curve and Comparison of Short-term Results With Standard Laparoscopic Total Mesorectal Excision

BACKGROUND

Ever since transanal total mesorectal excision was introduced by Sylla and Lacy in 2010, it has become more popular among colorectal surgeons. However, some surgeons hesitate to use it, because this novel approach differs greatly from laparoscopic total mesorectal excision and requires a long learning curve.

OBJECTIVE

This study analyzed the learning curve of transanal total mesorectal excision procedure and compared the different phases of transanal total mesorectal excision with laparoscopic total mesorectal excision.

DESIGN

This is retrospective case-control study.

SETTINGS

We used data from the approved colorectal cancer database of the Sixth Affiliated Hospital of Sun Yat-sen University.

PATIENTS

The patients involved in this study underwent transanal total mesorectal excision performed by a single surgeon (L.K.) or underwent laparoscopic transanal total mesorectal excision performed by experienced surgeons.

INTERVENTIONS

Transanal or laparoscopic resection of mid-low rectal cancer was conducted.

MAIN OUTCOMES MEASURES

Perioperative complication and resection margin were measured.

RESULTS

A total of 342 patients were included in both groups. The learning curve of transanal total mesorectal excision was divided into 3 phases. Data show that demographics and tumor characteristics were not significantly different between the matched groups. Indeed, during phase 1, only operative time was longer than in the laparoscopic group, whereas, during phase 2, results from the transanal group were comparable with the laparoscopic group. Results show that, during phase 3, operative time, intraoperative blood loss, and postoperative hospital stay were all lower than in the laparoscopic group. Local recurrence occurred in 3 patients during phase 1 and in 1 patient during phase 2.

LIMITATIONS

This study was a small retrospective study and focused on just 1 surgeon performing transanal total mesorectal excision.

CONCLUSIONS

Short-term and histopathologic outcomes are similar compared between a transanal group and matched laparoscopic group. Transanal total mesorectal excision also provided good oncologic outcomes. See Video Abstract at http://links.lww.com/DCR/B450.

ESCISIN MESORRECTAL TOTAL TRANSANAL EN EL CNCER DE RECTO MEDIOBAJO EVALUACIN DE LA CURVA DE APRENDIZAJE Y COMPARACIN DE RESULTADOS A CORTO PLAZO CON TME LAPAROSCPICA ESTNDAR

ANTECEDENTES:Desde que Sylla y Lacy introdujeron la escisión mesorrectal total transanal en 2010, se ha vuelto más popular entre los cirujanos colorrectales. Sin embargo, algunos cirujanos dudan en utilizarlo, porque este nuevo método difiere mucho de la escisión mesorrectal total laparoscópica y requiere una larga curva de aprendizaje.OBJETIVO:Este estudio analizó la curva de aprendizaje del procedimiento de escisión mesorrectal total transanal y comparó las diferentes fases de la escisión mesorrectal total transanal con la escisión mesorrectal total laparoscópica.DISEÑO:Este es un estudio retrospectivo de casos y controles.ENTORNO CLINICO:Utilizamos base de datos de cáncer colorrectal aprobada del Sexto Hospital Afiliado de la Universidad Sun Yat-sen (Guangzhou, China).PACIENTES:Los pacientes involucrados en este estudio fueron sometidos a escisión mesorrectal total transanal realizada por un solo cirujano (LK) o se sometieron a escisión mesorrectal total transanal laparoscópica realizada por cirujanos experimentados.INTERVENCIONES:Resección transanal o laparoscópica de cáncer de recto medio-bajo.PRINCIPALES MEDIDAS DE VOLARCION:complicación perioperatoria y margen de resección.RESULTADOS:Se incluyó un total de 342 pacientes en ambos grupos. La curva de aprendizaje de la escisión mesorrectal total transanal se dividió en tres fases. Los datos muestran que las características demográficas y tumorales no fueron significativamente diferentes entre los grupos emparejados. De hecho, durante la fase 1, solo el tiempo operatorio fue más largo que en el grupo laparoscópico. Mientras que durante la fase 2, los resultados del grupo transanal fueron comparables a los del grupo laparoscópico. Los resultados muestran que durante la fase 3, el tiempo operatorio, la pérdida de sangre intraoperatoria y la estancia hospitalaria postoperatoria fueron menores que en el grupo laparoscópico. La recurrencia local ocurrió en 3 pacientes durante la fase 1 y en 1 paciente durante la fase 2.LIMITACIONES:Este estudio fue un estudio retrospectivo pequeño y se centró en un solo cirujano que realizaba la escisión mesorrectal total transanal.CONCLUSIÓN:Los resultados a corto plazo e histopatológicos son similares en comparación entre el grupo transanal y el grupo laparoscópico emparejado. La escisión mesorrectal total transanal también proporcionó buenos resultados oncológicos. Consulte Video Resumen en http://links.lww.com/DCR/B450.

A case of carbon dioxide embolism during the transperineal approach in total pelvic exenteration for advanced anorectal cancer

The transanal and transperineal endoscopic approaches are useful advanced surgical options for removing rectal and anorectal cancers. Intraoperative carbon dioxide (CO₂ ) embolisms, however, have been increasingly reported as potentially fatal complications associated with surgery employing these approaches. We report our experience with a CO₂ embolism that was detected because of a sudden drop in end-tidal CO₂ with decreasing saturation of percutaneous arterial oxygen during total pelvic exenteration using the transperineal endoscopic approach under pneumopelvis/pneumoperitoneum. Transesophageal echocardiography confirmed that it was a CO₂ embolus. We reversed the pneumopelvis and pneumoperitoneum, which alleviated the cardiopulmonary problems, and the surgery then proceeded to achieve R0 resection. The patient was discharged without severe complications other than the CO₂ embolism.

Carbon dioxide embolism during transanal total mesorectal excision (TaTME): two case reports

Transanal total mesorectal excision (TaTME), a new approach for rectal cancers, requires transanal carbon dioxide (CO2) high-flow insufflation to create a workplace. Two patients scheduled for TaTME experienced CO2 embolism during the anterior mesorectal dissection in contact with the prostate. CO2 embolism resulted in a sudden drop of end-tidal CO2, preceded by a short increase in one patient, and in oxygen desaturation. Hemodynamic alterations were minor. We report these two cases and discuss the pathophysiology of CO2 embolism and risk factors that promote CO2 embolism during TaTME to warn anesthetists of this serious complication, often unexpected and misdiagnosed.