Improving Quality in Colorectal Surgery

__Abstract__ Colorectal surgery is an important aspect of our current health system, due to the high incidence of colorectal cancer combined with an ageing population, improved long-term outcomes after colorectal surgery, and the perfectioning of the operative and postoperative aspects through laparoscopy and enhanced recovery programs. However, postoperative complications painfully remain, despite efforts of amelioration of perioperative care. Research for molecular pathways and non-surgical treatment modalities of colorectal cancer and inflammatory bowel disease is rising in importance, however the improvement of quality and safety of colorectal surgery should remain and become ever more a key element for all colorectal surgeons. This thesis aims to add to this improvement

Prediction of fluid responsiveness using respiratory variations in left ventricular stroke area by transoesophageal echocardiographic automated border detection in mechanically ventilated patients.

BackgroundLeft ventricular stroke area by transoesophageal echocardiographic automated border detection has been shown to be strongly correlated to left ventricular stroke volume. Respiratory variations in left ventricular stroke volume or its surrogates are good predictors of fluid responsiveness in mechanically ventilated patients. We hypothesised that respiratory variations in left ventricular stroke area (DeltaSA) can predict fluid responsiveness.MethodsEighteen mechanically ventilated patients undergoing coronary artery bypass grafting were studied immediately after induction of anaesthesia. Stroke area was measured on a beat-to-beat basis using transoesophageal echocardiographic automated border detection. Haemodynamic and echocardiographic data were measured at baseline and after volume expansion induced by a passive leg raising manoeuvre. Responders to passive leg raising manoeuvre were defined as patients presenting a more than 15% increase in cardiac output.ResultsCardiac output increased significantly in response to volume expansion induced by passive leg raising (from 2.16 +/- 0.79 litres per minute to 2.78 +/- 1.08 litres per minute; p < 0.01). DeltaSA decreased significantly in response to volume expansion (from 17% +/- 7% to 8% +/- 6%; p < 0.01). DeltaSA was higher in responders than in non-responders (20% +/- 5% versus 10% +/- 5%; p < 0.01). A cutoff DeltaSA value of 16% allowed fluid responsiveness prediction with a sensitivity of 92% and a specificity of 83%. DeltaSA at baseline was related to the percentage increase in cardiac output in response to volume expansion (r = 0.53, p < 0.01).ConclusionDeltaSA by transoesophageal echocardiographic automated border detection is sensitive to changes in preload, can predict fluid responsiveness, and can quantify the effects of volume expansion on cardiac output. It has potential clinical applications

Optimizing working-space in laparoscopy: Measuring the effect of mechanical bowel preparation in a porcine model

Background: Adequate working space is a prerequisite for safe and efficient minimal access surgery. No objective data exist in literature about the effect of mechanical bowel preparation (MBP) on working space in laparoscopic surgery. We objectively measured this effect with computed tomography in a porcine laparoscopy model. Methods: Using standardized anesthesia, twelve 20-kg pigs without MBP and eight 20-kg pigs with MBP were studied with computed tomography at intra-abdominal pressure (IAP) levels of 0, 5, 10, and 15 mmHg. Volumes and dimensions of the pneumoperitoneum were measured on reconstructed CT images and compared between the pigs with and those without MBP. Results: A reproducible and statistically significant increase of approximately 500 ml in pneumoperitoneum volume was found in the MBP group at all levels of IAP. This represents a 43 % relative increase at a pneumoperitoneum pressure of 5 mmHg, 21 % at IAP 10 mmHg, and 18 % at IAP 15 mmHg. Peak inspiratory pressure was lower at IAP 0 and 5 mmHg in the MBP group. Anteroposterior diameter in the group with MBP was lower at 0 mmHg, but abdominal dimensions were similar in both groups at all other IAPs. This shows that the gain in working space is due to a diminished volume of the intra-abdominal content and not to compression or displacement of the bowel. Conclusions: MBP increases working space by reducing bowel content. Especially at low intra-abdominal working pressures, the increase in working space associated with MBP could represent an important benefit in challenging laparoscopic surgery

Training in laparoscopic colorectal surgery: A new educational model using specially embalmed human anatomical specimen

Background: With an increasing percentage of colorectal resections performed laparoscopically nowadays, there is more emphasis on training "before the job" on operative skills, including the comprehension of specific laparoscopic surgical anatomy. As integration of technical skills with correct interpretation of the anatomical image must be incorporated in laparoscopic training, a human specimen training model with special emphasis on surgical anatomy was developed. Methods: The new embalming method Anubifix ™ combines long-term high-quality embalming of human bodies with almost normal flexibility and plasticity, and the body can be kept operational as long as conventionally embalmed human specimens. A colorectal training model was created in a specimen in which anatomical landmarks of colorectal anatomy were permanently colored to explore laparoscopic colorectal anatomy in a skills training setting. Airtight closure of the abdominal wall permits the creation of pneumoperitoneum. Residents were asked to test the model by mobilizing the small and large bowels and expose the central vessels and ureters. Afterward they were asked to fill out an eight-item questionnaire about the model. Results: Eleven surgical residents in their first and second year of training participated. Responses to the questionnaire showed that a majority of residents considered the model to be representative of the real situation and superior to animal models or virtual reality simulators, and helped to improve the knowledge of three-dimensional anatomy and laparoscopic skills. Conclusion The new training model for laparoscopic colorectal: surgery proved to be a high-quality tool, concentrating on laparoscopic colorectal anatomy in a skills training setting. We believe it may be a valuable adjunct to residency training programs based on the principle of "trainin

Effects of new anti-adhesion polyvinyl alcohol gel on healing of colon anastomoses in rats

Background: Adhesions follow abdominal surgery with an incidence as high as 95%, resulting in invalidating complications such as bowel obstruction, female infertility, and chronic pain. Searches have been performed for a safe and effective adhesion barrier; however, such barriers have impaired anastomotic site healing. The primary aim of this study was to investigate the effect of a new adhesion barrier, polyvinyl alcohol gel, on healing of colonic anastomoses using a rat model. Methods: Thirty-two Wistar rats were divided in two groups. In all animals, an anastomosis was constructed in the ascending colon. The first group received no adhesion barrier, whereas in the second group, 2mL of polyvinyl alcohol gel (A-Part Gel®; Aesculap AG, Tuttlingen, Germany) was applied circularly around the anastomosis. All animals were sacrificed on the seventh post-operative day, and the abdomen was inspected for signs of anastomotic leakage. The anastomotic bursting pressure, the adhesions around the anastomosis, and the collagen content of the excised anastomosis were measured. Results: No significant differences were observed between the two groups in the incidence of anastomotic leakage, the anastomotic bursting pressure (p=0.08), or the collagen concentration (p=0.91). No significant reduction in amount of adhesions was observed in the rats receiving polyvinyl alcohol gel. Conclusions: This experimental study showed no significant differences in anastomotic leakage, anastomotic bursting pressure, or collagen content of the anastomosis when using the adhesion barrier polyvinyl alcohol around colonic anastomoses. The barrier did not prevent adhesion formation

High tie versus low tie in rectal surgery: comparison of anastomotic perfusion

Item does not contain fulltextPURPOSE: Both "high tie" (HT) and "low tie" (LT) are well-known strategies in rectal surgery. The aim of this study was to compare colonic perfusion after HT to colonic perfusion after LT. METHODS: Patients undergoing rectal resection for malignancy were included. Colonic perfusion was measured with laser Doppler flowmetry, immediately after laparotomy on the antimesenterial side of the colon segment that was to become the afferent loop (measurement A). This measurement was repeated after rectal resection (measurement B). The blood flow ratios (B/A) were compared between the HT group and the LT group. RESULTS: Blood flow was measured in 33 patients, 16 undergoing HT and 17 undergoing LT. Colonic blood flow slightly decreased in the HT group whereas the flow increased in the LT group. The blood flow ratio was significantly higher in the LT group (1.48 vs. 0.91; p = 0.04), independent of the blood pressure. CONCLUSION: This study shows the blood flow ratio to be higher in the LT group. This suggests that anastomoses may benefit from better perfusion when LT is performed

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

Natural Orifice Transluminal Endoscopic Surgery: Long-Term Experience with Hybrid Transvaginal Cholecystectomies

Objective. To assess outcome and safety of 571 hybrid natural orifice transluminal endoscopic surgery (NOTES) cholecystectomies. Methods. We retrospectively analyzed all consecutive NOTES cholecystectomies performed at our center between June 2009 and January 2018. All procedures were performed using a hybrid transvaginal technique, including an umbilical small-size trocar. End points, calculated at discharge, 30 and up to 90 days postoperatively, included intra- and postoperative morbidity assessed by the validated Clavien–Dindo classification and the Comprehensive Complication Index (CCI). Special focus was held on outcome and necessity of pre- and postoperative gynecological examinations. Results. We performed 571 hybrid NOTES cholecystectomies within 9 years. The vast majority were elective, 9.6% were emergency cholecystectomies. 6.7% of patients developed at least one complication until discharge, most of them minor (≤grade II). 30- and 90-day complication rates were 10.7% and 11%, respectively. Mean CCI at discharge and postoperative days 30 and 90 was 1.45 (±6.4), 2.3 (±7.7), and 2.4 (±7.8), respectively. Major complications (≥grade IIIa) occurred in 1.6% of patients, and 4 patients required emergency reoperation. No mortality was observed. In 9.8%, an additional abdominal trocar was placed. All patients underwent routine gynecological examination, whereof only 5 were rejected for transvaginal access preoperatively. In no case transvaginal access was discontinued intraoperatively due to gynecological disease. Conclusion. Hybrid NOTES transvaginal cholecystectomy represents a safe and feasible alternative to standard laparoscopic cholecystectomy. Preoperative gynecological examination is no longer routinely necessary, as intraoperative assessment is adequate

Does Coffee Intake Reduce Postoperative Ileus After Laparoscopic Elective Colorectal Surgery?: A Prospective, Randomized Controlled Study: The Coffee Study

BACKGROUND Postoperative ileus after colorectal surgery is a frequent problem that significantly prolongs hospital stay and increases perioperative costs. OBJECTIVE The aim was to evaluate the effect of standardized coffee intake on postoperative bowel movement after elective laparoscopic colorectal resection. DESIGN This is a prospective randomized controlled trial that was conducted between September 2014 and December 2016. SETTINGS This study was performed in a public cantonal hospital in Switzerland with accreditation for colon and rectum cancer surgery. PATIENTS Patients who underwent elective colorectal surgery were included. INTERVENTIONS Patients were randomly assigned either to the intervention group receiving coffee or the control group receiving tea. A total of 150 mL of the respective beverage was drunk 3 times per day every postoperative day until discharge. MAIN OUTCOME MEASURES The primary end point was time to first bowel movement. Secondary end points included the use of laxative, insertion of a nasogastric tube, length of hospital stay, and postoperative complications. RESULTS A total of 115 patients were randomly assigned: 56 were allocated to the coffee group and 59 to the tea group. After coffee intake, the first bowel movement occurred after a median of 65.2 hours versus 74.1 hours in the control group (intention-to-treat analysis; p = 0.008). The HR for earlier first bowel movement after coffee intake was 1.67 (p = 0.009). In the per-protocol analysis, hospital stay was shorter in the coffee group (6 d in the coffee group vs 7 d in the tea group; p = 0.043). LIMITATIONS The rate of protocol violation, mostly coffee consumption in the tea arm, was relatively high, even if patients were clearly instructed not to consume coffee if they were in the tea arm. CONCLUSIONS Coffee intake after elective laparoscopic colorectal resection leads to faster recovery of bowel function. Therefore, coffee intake represents a simple and effective strategy to prevent postoperative ileus. See Video Abstract at http://links.lww.com/DCR/A955

Prevention of leakage by sealing colon anastomosis: experimental study in a mouse model

Background: In colorectal surgery, anastomotic leakage (AL) is the most significant complication. Sealants applied around the colon anastomosis may help prevent AL by giving the anastomosis time to heal by mechanically supporting the anastomosis and preventing bacteria leaking into the peritoneal cavity. The aim of this study is to compare commercially available sealants on their efficacy of preventing leakage in a validated mouse model for AL. Methods: Six sealants (Evicel, Omnex, VascuSeal, PleuraSeal, BioGlue, and Colle Chirurgicale Cardial) were applied around an anastomosis constructed with five interrupted sutures in mice, and compared with a control group without sealant. Outcome measures were AL, anastomotic bursting pressure, and death. Results: In the control group there was a 40% death rate with a 50% rate of AL. None of the sealants were able to diminish the rate of AL. Furthermore, use of the majority of sealants resulted in failure to thrive, increased rates of ileus, and higher mortality rates. Conclusions: If sealing of a colorectal anastomosis could achieve a reduction of incidence of clinical AL, this would be a promising tool for prevention of leakage in colorectal surgery. In this study, we found no evidence that sealants reduce leakage rates in a mouse model for AL. However, the negative results of this study make us emphasize the need of systemic research, investigating histologic tissue reaction of the bowel to different sealants, the capacity of sealants to form a watertight