Routine conventional leak test is not required for robotic major pulmonary resections.

OBJECTIVE: We retrospectively evaluated whether or not conventional air leak testing is necessary in robotic major pulmonary resections. METHODS: After excluding patients who received 2 or more days of postoperative drainage for chylothorax or excessive pleural effusion, 578 patients who underwent major pulmonary resection using minimally invasive approaches between February 2019 and November 2023 at our institution were included in this study. All patients were divided into two groups including thoracoscopic (n = 471) and robotic (n = 107) approaches. Conventional air leak testing was performed in all patients in the thoracoscopic approach but not in the robotic approach. After propensity score matching of patient backgrounds between the two groups, perioperative outcomes were compared (n = 100 each). The primary endpoint was the rate of drain removal on postoperative day (POD) 2 or later. In addition, factors associated with drain removal on POD 2 or later in the robotic group were identified. RESULTS: The rate of drain removal at POD 2 or later was not significantly different between the two groups (p = 0.011). Multivariable analysis to identify factors associated with drain removal at POD2 or later in the robotic approach showed that sealant application (p = 0.002) and lobectomy (vs. segmentectomy, p = 0.034) were significantly associated. CONCLUSIONS: In conclusion, even in the absence of air leak testing, a robotic approach for major lung resections can result in a drain removal rate on the day of surgery or POD1 that is comparable to a conventional thoracoscopic approach. However, it may be useful in selected patients requiring sealant placement or undergoing lobectomy.

Intraoperative left-sided colorectal anastomotic testing in clinical practice: a multi-treatment machine-learning analysis of the iCral3 prospective cohort.

BACKGROUND: Current evidence about intraoperative anastomotic testing after left-sided colorectal resections is still controversial. The aim of this study was to analyze the impact of Indocyanine Green fluorescent angiography (ICG-FA) and air-leak test (ALT) over standard assessment on anastomotic leakage (AL) rates according to surgeon's perception of anastomosis perfusion and/or integrity in clinical practice. METHODS: A database of 2061 patients who underwent left-sided colorectal resections was selected from patients enrolled in a prospective multicenter study. It was retrospectively analyzed through a multi-treatment machine-learning model considering standard visual assessment (NW; No. = 899; 43.6%) as the reference treatment arm, compared to ICG-FA alone (WP; No. = 409; 19.8%), ALT alone (WI; No. = 420; 20.4%) or both (WPI; No. = 333; 16.2%). Twenty-four covariates potentially affecting the outcomes were included and balanced into the model within the subgroups. The primary endpoint was AL, the secondary endpoints were overall morbidity (OM), major morbidity (MM), reoperation for AL, and mortality. All the results were reported as odds ratio (OR) with 95% confidence intervals (95%CI). RESULTS: The WPI subgroup showed significantly higher AL risk (OR 1.91; 95% CI 1.02-3.59; p 0.043), MM risk (OR 2.35; 95% CI 1.39-3.97; p 0.001), and reoperation for AL risk (OR 2.44; 95% CI 1.12-5.31; p 0.025). No other significant differences were recorded. CONCLUSIONS: This study showed that the surgeons' perception of both anastomotic perfusion and integrity (WPI subgroup) was associated to a significantly higher risk of AL and related morbidity, notwithstanding the extensive use of both ICG-FA and ALT testing.

Efficacy of air leak test in detection of anastomotic leaks after rectal excision: a retrospective case-controlled study.

Purpose: Although its efficacy is uncertain, an intraoperative air leak test (ALT) is commonly used to detect mechanical defects following bowel anastomosis. This study aimed to evaluate the efficacy of ALT to detect anastomotic leakage (AL) following rectal excision. Methods: We reviewed our database for patients with rectal cancers who had undergone curative surgery between January 2012 and January 2018. Patients were grouped according to whether or not an ALT was performed. Propensity score analyses were performed to compare outcomes for groups in a 1:1 case-matched cohort. Results: In total, 1,191 patients underwent rectal excision; 438 (219 in each group) formed the case-matched cohort for analysis. The protective stoma rate was 16.0% and 14.6% in the ALT and the no-ALT groups, respectively (P = 0.791). In the ALT group, 2 patients (0.9%) showed a positive result and were treated with rectal tube drainage, resulting in no leakage. There was no significant difference in postoperative AL rate between the groups (ALT group: 4.6% vs. no-ALT group: 4.1%, P > 0.999). Conclusion: ALT played a minimal role in detecting AL following rectal excision. Further studies are warranted to validate our results and clarify whether AL can be prevented with ALT or alternative methods.

Techniques for Diagnosing Anastomotic Leaks Intraoperatively in Colorectal Surgeries: A Review.

Colorectal cancer is one of the most common surgically curable malignancies worldwide, having a good prognosis even with liver metastasis. This improved patient outcome is marred by anastomotic leaks (AL) in operated patients of colorectal cancer despite a microscopically margin-negative resection (R0). Various risk factors have been attributed to causing this. Preoperative non-modifiable factors are age, male sex, cancer cachexia, and neoadjuvant chemo-radiotherapy, and modifiable factors are comorbidities, peripheral vascular disease, anemia, and malnutrition. Intraoperative risk factors include intraoperative surgical duration, blood loss and transfusions, fluid management, oxygen saturation, surgical technique (stapled, handsewn, or compression devices), and approach (open, laparoscopic, or robotic). Postoperative factors like anemia, infection, fluid management, and blood transfusions also have an effect. With the advent of enhanced recovery after surgery (ERAS) protocols, many modifiable factors can be optimized to reduce the risk. Prevention is better than cure as the morbidity and mortality of AL are very high. There is still a need for an intraoperative technique to detect the viability of anastomotic ends to predict and prevent AL. Prompt diagnosis of an AL is the key. Many surgeons have proposed using methods like air leak tests, intraoperative endoscopy, Doppler ultrasound, and near-infrared fluorescence imaging to decrease the incidence of AL. All these methods can minimize AL, resulting in significant intraoperative alterations to surgical tactics. This narrative review covers the methods of assessing of integrity of anastomosis during the surgery, which can help prevent anastomotic leakage.

Comprehensive testing of colorectal anastomosis: results of prospective observational cohort study.

BACKGROUND: Anastomotic leakage remains one of the most threatening complications in colorectal surgery. Intraoperative testing of anastomosis may reduce the postoperative anastomotic leakage rates. This study aimed to investigate a novel comprehensive intraoperative colorectal anastomosis testing technique to detect the failure of the anastomosis construction and to reduce the risk of postoperative leak. METHODS: This multi-centre prospective cohort pilot study included 60 patients who underwent colorectal resection with an anastomosis at or below 15 cm from the anal verge. Comprehensive trimodal testing consisted of indocyanine green fluorescence angiography, tension testing, air-leak, and methylene blue leak tests to evaluate the perfusion, tension, and mechanical integrity of the anastomosis. RESULTS: Ten (16.7%) patients developed an anastomotic leakage. Trimodal test was positive in 16 (26.6%) patients and the operative plan was changed for all of them. Diverting ileostomy was performed in 14 (87.5%) patients. However, two (12.5%) patients still developed clinically significant anastomotic leakage (Grade B). Forty-four (73.4%) patients had a negative trimodal test, preventive ileostomy was performed in 19 (43.2%), and five (11.4%) patients had clinically significant anastomotic leakage (Grade B and C). CONCLUSION: Trimodal testing identifies anastomoses with initial technical failure where reinforcement of anastomosis or diversion can lead to an acceptable rate of anastomotic leakage. Identification of well-performed anastomosis could allow a reduction of ileostomy rate by two-fold. However, anastomotic leakage rate remains high in technically well-performed anastomoses.

The "reverse air leak test": a new technique for the assessment of low colorectal anastomosis.

PURPOSE: Anastomotic leakage is a fearsome complication in rectal surgery. Surgeons perform the classic air leak test, although its real effectiveness is still debated. The aim of this study was to describe a personal technique of reverse air leak test in which low colorectal anastomosis was assessed transanally through the intrarectal irrigation of a few mL of saline solution. METHODS: From October 2014 to November 2019, 11 patients with low rectal cancer (type 1 in Roullier classification) were included in this study. At the beginning of the procedure, a circular anal dilator was inserted into the anus. A side-to-end colorectal anastomosis was performed. A few mL of saline solution were injected into the rectum and the entire anastomotic line was directly explored. The appearance of bubbles was considered as an anastomotic defect and repaired with an interrupted suture. A fluorescence angiography after intravenous injection of indocyanine green was performed in order to evaluate the perfusion of the anastomosis. RESULTS: The reverse air leak test was positive in 4 cases (36.4%). The defect was repaired and a confirmation test was performed. In all patients, near-infrared evaluation showed no perfusion defect (grade 0) in low colorectal anastomosis. No postoperative fistula was detected in cohort study. A protective stoma was performed in 10 patients. On day 90, there were no complications and stoma closure was performed as planned. CONCLUSION: The reverse air leak test is a simple, feasible, and effective procedure to identify anastomotic leaks in low colorectal anastomoses.

Anastomotic Troubleshooting.

Anastomotic leak remains a critical and feared complication in colorectal surgery. The development of a leak can be catastrophic for a patient, resulting in overall increased morbidity and mortality. To help mitigate this risk, there are several ways to assess and potentially validate the integrity of a new anastomosis to give the patient the best chance of avoiding this postoperative complication. A majority of anastomoses will appear intact with no obvious sign of anastomotic dehiscence on gross examination. However, each anastomosis should be interrogated before the conclusion of an operation. The most common method to assess for an anastomotic leak is the air leak test (ALT). The ALT is a safe intraoperative method utilized to test the integrity of left-sided colon and rectal anastomoses and most importantly allows the ability to repair a failed test before concluding the operation. Additional troubleshooting is sometimes needed due to technical difficulties with the circular stapler. Problems, such as incomplete doughnuts and stapler misfiring, do occur and each surgeon should be prepared to address them.

Experimental Study of Mechanical Integrity Testing in Stapled Large Bowel: Methylene Blue Leak Test Is Not Inferior to Air Leak Test.

BACKGROUND/OBJECTIVES: Anastomotic leakage remains the most devastating postoperative complication in colorectal surgery. The mechanical integrity of the newly formed colorectal anastomosis can be evaluated by visual inspection intraoperatively; both air leak and liquid leak tests are also used to evaluate the integrity of stapled colorectal anastomoses. It is not clear whether double-stapled anastomoses are more prone to leaks than single-stapled anastomoses. The aim of our study was to compare the methylene blue and the air leak test in the experimental setting of single-stapled and double-stapled porcine bowels. METHODS: Twenty-four distal colons were excised from slaughtered pigs without delay. The proximal bowel end was closed with a linear stapler using blue cartridges. The bowels were randomly divided into single-stapled or double-stapled groups. Air leak and methylene blue leak tests were performed. A digital pressure monitor with a gradual pressure increase function was used to both gradually increase pressure within the bowel and to determine the pressure at which the stapler line disintegrated. RESULTS: Air leakage occurred at a mean pressure of 51.62 (±16.60) mm Hg and methylene blue leakage occurred at 46.54 (±16.78) mm Hg (p = 0.31). The air and methylene blue leaks occurred at comparable pressures in single-stapled bowels and in double-stapled bowels (47.21 [±14.02] mm Hg vs. 50.96 [±19.15] mm Hg, p = 0.6). CONCLUSIONS: The methylene blue solution leak test is not inferior to the air leak test. There is no significant difference in bursting pressure between single-stapled and double-stapled anastomoses.

Intraoperative evaluation of colorectal anastomotic integrity: a comparison of air leak and dye leak tests.

BACKGROUND: Air leak tests (ALTs) and dye leak tests (DLTs) are the most common techniques for Intraoperative colorectal anastomosis assessment. The aim of our study was to compare the sensitivity of ALT with DLT in intraoperative evaluation of colorectal anastomotic integrity and to quantify the pressures routinely used in these tests. METHODS: A prospective clinical trial was conducted on patients who had elective colorectal resection and primary anastomosis from November 2017 until July 2019 in a single academic referral center. Each patient underwent both tests. The ALT was a transanal insufflation of CO2 and inspection of escaping bubbles around the anastomosis immersed in saline. The DLT was a transanal infusion of diluted methylene blue and inspection of dye stains on surgical gauze wrapping the anastomosis. Peak pressures were measured. Primary endpoints were the sensitivity of ALT and DLT in detecting intraoperative leaks, quantification of intraluminal pressure routinely used in these settings and assessment of postoperative complications such as a clinical leak. RESULTS: Forty patients underwent elective colorectal resection and anastomosis for malignant (67%) or benign n (33%) etiology. Height of anastomoses ranged from 1 to 25 cm (mean ± SD 12 ± 6 cm). Mean pressures measured were 26.5 ± 6.6 mmHg for the DLT and 22 ± 4 mmHg for the ALT (p < 0.01). Twenty percent of the DLTs were positive (8 patients) compared to 2.5% (1 patient) of the ALTs (RR 1.97, CI 1.2-2.7; p = 0.03). All patients who had positive tests had a suture reinforcement of the anastomosis. Only 1 patient, who had a positive DLT and ALT, developed a clinical leak CONCLUSIONS: DLT is more sensitive in detecting anastomotic leak intraoperatively. This is the first study measuring anastomotic tests' pressures used in-vivo in humans demonstrating a range of 20-30 mmHg. Based on our data we believe that a positive DLT with a negative ALT may be treated with suture reinforcement alone. CLINICAL TRIAL NUMBER: NCT03316677-10/17/2017.

Successful detection of rectal injury during laparoscopic surgery using a rectal probe in a patient with deep endometriosis.

Laparoscopic surgery has become the gold standard treatment for endometriosis. Surgical treatment of deep endometriosis with colorectal involvement is challenging. It requires complete surgical excision of lesions despite a high risk of complications that include rectal injury, rectovaginal fistula and pelvic abscess. An intraoperative air leak test allows detection of rectal injury and reduces postoperative complications. We report a case of successful management of rectal injury during laparoscopic surgery using a rectal probe even though air leak tests were negative. A 45-year-old woman with severe endometriosis and rectal involvement underwent total laparoscopic hysterectomy combined with rectal shaving. A pinhole injury that reached the rectal muscularis layer without breaching the mucosal layer was identified using a rectal probe after negative air leak tests. The injury was repaired uneventfully. Our experience suggests that using a rectal probe could be helpful for early detection and safe repair of rectal injury during surgery.