Impact of obesity on surgical outcomes after colorectal resection

Risk factors for postoperative complications in patients undergoing cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy: A meta-analysis and systematic review

OBJECTIVE

Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) is one of the most effective treatments for intraperitoneal malignancies. However, current research on risk factors for postoperative complications needs to be more consistent. This study aimed to conduct a meta-analysis of the risk factors for postoperative complications in CRS + HIPEC patients.

METHODS

Studies meeting the inclusion criteria were screened by searching the Embase, PubMed, Cochrane and Web of Science databases. RevMan and STATA software were used to analyze the data extracted from the included articles.

RESULTS

A total of 15 articles with 4021 patients were included in the meta-analysis. The results revealed that sex, elevated peritoneal cancer index, prolonged duration of surgery and smoking habits were risk factors for postoperative complications in CRS + HIPEC patients. In contrast, BMI, eGFR, age, history of preoperative chemotherapy, history of preoperative surgery, and history of neoadjuvant therapy had no significant effect on postoperative complications in the CRS + HIPEC group. The effects of diabetes, hypertension, preoperative albumin level, tumor location and chemotherapy regimen on the occurrence of complications need to be further investigated.

CONCLUSIONS

We identified several risk factors for postoperative complications after CRS + HIPEC, which should help clinicians minimize the incidence of postoperative complications and make more beneficial decisions for cancer patients who need treatment.

Association between body mass index and short-term outcomes of laparoscopic right hemicolectomy for colon cancer

BACKGROUND

Laparoscopic right hemicolectomy can be technically challenging in patients with increased body mass index, reportedly associated with higher surgical site infection (SSI) and incisional hernia rates. We aimed to assess the association between increased body mass index and short-term outcomes of laparoscopic right hemicolectomy.

METHODS

This retrospective cohort study included patients with colon cancer who underwent laparoscopic right hemicolectomy between 2011 and 2021. Patients were managed with a standardized care protocol that comprised preoperative, intraoperative, and postoperative measures and were divided according to body mass index-normal body mass index (18-24.9 kg/m2), overweight (25-29.9 kg/m2), and obesity (≥30 kg/m2). Body mass index groups were compared for baseline characteristics and outcomes. The main outcome measures were operative time, hospital stay, 30-day complications, reoperation, number of harvested lymph nodes, and resection status.

RESULTS

A total of 270 patients (50% male sex; mean age: 68.7 ± 13.5 years) were included-28.5% had normal body mass index, 47% were overweight, and 24.5% had obesity. Mean operative times in obese and overweight patients were significantly longer than patients with normal body mass index (172.1 and 168.8 versus 143.3 minutes, P = .01). Compared to normal body mass index, obesity was associated with significantly higher odds of incisional SSI (odds ratio: 9.29, P = .039). Body mass index had a significant positive correlation with operation time (r = 0.205, P = .004) and incisional SSI (r = 0.126, P = .04). Body mass index groups had similar hospital stays, 30-day complications and mortality, anastomotic leak, ileus, and reoperation.

CONCLUSION

Patients with increased body mass index had longer operative times and higher SSI rates, yet similar hospital stays and comparable 30-day complication rates, mortality, and reoperation to patients with normal body mass index.

The feasibility and outcomes of metabolic and bariatric surgery prior to neoplastic therapy

BACKGROUND

Metabolic and bariatric surgery (MBS) is a potent intervention for addressing obesity-related medical conditions and achieving sustainable weight loss. Beyond its conventional role, MBS has demonstrated potential to serve as a transitional step for patients requiring various interventions. However, the implications of MBS in the context of neoplasia remain understudied.

OBJECTIVES

To explore the feasibility of MBS as a possible attempt to reduce surgical and treatment risks in patients with benign tumors or low-grade cancers.

SETTING

Multicenter review from twelve tertiary referral centers spanning 8 countries.

METHODS

A retrospective review of patients with a diagnosis of primary neoplasia, deemed inoperable or high-risk due to obesity, and receiving primary MBS prior to neoplastic therapy. Data encompassed baseline characteristics, neoplasia characteristics, MBS outcomes, and neoplastic therapy outcomes.

RESULTS

Thirty-seven patients (median age 52 years, 75.7% female, median BMI of 49.1 kg/m2) were included. There were 9 distinct organs of origin of primary neoplasia, with the endometrium (43.2%) being the most common, followed by the pancreas, colon, kidney and breast. Sleeve gastrectomy (SG) was the most commonly performed MBS procedure (78.4%), with no MBS-related complications or mortalities reported over an average of 4.3 ± 3.9 years. Thirty-one patients (83.8%) eventually underwent neoplastic surgery, with a mean BMI decrease from 49.9 kg/m2 to 39.7 kg/m2 at surgery over an average of 5.8 ± 4.8 months. There were 2 (6.7%) documented mortalities associated with neoplastic surgical intervention.

CONCLUSIONS

This study highlights the potential feasibility of employing MBS prior to neoplastic therapy in patients with low-grade, less aggressive neoplasms in the context of obesity. This underscores the importance of providing a personalized, case-to-case multidisciplinary approach in the management of these patients.

Role of body mass index in anastomotic leakage after curative treatment for rectal cancer

BACKGROUND

Anastomotic leakage (AL) represents a severe complication after rectal surgery, leading to significant morbidity, mortality, and increased healthcare costs. Despite improvements in surgical methods and perioperative care, the challenge of AL persists.

OBJECTIVES

Explore the impact of body mass index (BMI) on the risk of AL following curative treatment for rectal cancer, providing insight into its predictive value.

DESIGN

Retrospective review.

SETTINGS

Data were collected from a single tertiary center, emphasizing the specialized postoperative outcomes in a high-care setting.

PATIENTS AND METHODS

The study population was comprised patients who underwent sphincter-saving surgery combined with neoadjuvant chemoradiation for rectal cancer from 2001 to 2011. Patients with anastomotic stenosis were excluded.

MAIN OUTCOME MEASURES

The primary outcome investigated was the occurrence of AL post-surgery. Secondary outcomes included the assessment of local cancer recurrence rates within the AL group.

SAMPLE SIZE

224; 13 excluded.

RESULTS

Of 237 patients who underwent surgery, 13 with anastomotic stenosis were excluded from this study. Of the remaining 224, 15 individuals (6.3%) developed AL. A potential association between higher BMI and increased AL risk was identified. Additionally, the study noted a higher incidence of local rectal cancer recurrence in the group that developed leakage.

CONCLUSION

The findings suggest BMI as a significant predictive factor for AL after curative rectal cancer treatment. This emphasizes the need for heightened awareness and possible preoperative counseling for obese patients regarding their increased risk of postoperative leakage.

LIMITATIONS

The study was retrospective with all the inherit biases of such studies. The sample size was small and this may have introduced a type 2 statistical error.

The Impact of Obesity on Inflammatory Bowel Disease

Obesity is prevalent in the inflammatory bowel disease (IBD) population, particularly in newly developed countries where both IBD and obesity in the general population are on the rise. The role of obesity in the pathogenesis of IBD was entertained but results from available studies are conflicting. It does, however, appear to negatively influence disease course whilst impacting on our medical and surgical therapies. The pro-inflammatory profile of the visceral adipose tissue might play a role in the pathogenesis and course of Crohn's Disease (CD). Interestingly, isolating the mesentery from the surgical anastomosis using a KONO-S technique significantly decreases anastomotic recurrence rate. Anti-obesity therapy is not widely used in IBD but was suggested as an adjunctive therapy in those patients. In this review, we aimed to highlight the epidemiology of obesity in IBD and to describe its influence on disease course and outcomes.

Robotic CME in obese patients: advantage of robotic ultrasound scan for vascular dissection

Complete mesocolic excision (CME) in right-sided colon cancers appears to confer oncological benefits compared to conventional colectomy. Identification of the superior mesenteric vein (SMV) remains challenging. We describe the novel use of intra-operative robotic ultrasound scan (rUSS) in obese patients (BMI ≥ 29). All consecutive patients having robotic CME for colon cancer between 2014 and 2017 were included in this retrospective cohort study. Data were recorded on an ethics approved prospective database and included patient demographics, clinical and oncological outcomes. Patients were divided into group 1 (BMI ≤ 28) and group 2 (BMI ≥ 29). SMV first approach was employed in all cases and SMV detection was aided using rUSS in group 2. Primary outcome was postoperative morbidity. Secondary outcomes included conversion rate, operative time and length of stay (LOS). 41 (group 1, median 66 years) were compared to 32 patients (group 2, median 63 years). There were no conversions to laparoscopy or laparotomy. Median operative times for group 2 were 30 min longer (186 vs. 216 min, p = 0.05). Overall morbidity was similar (20% vs. 19% in group 1 and 2, p = 0.26). There was no significant difference between the two groups with regard to LOS (median 7 vs. 6 days, p = 0.48), readmissions (2 vs. 5, p = 0.13), R0 resection rate (98% vs. 94%, p = 0.43) and lymph node harvest (median 31 vs. 30, p = 0.28).CME can be technically more challenging than conventional colectomy in obese patients and is associated with longer operative times. The use of rUSS in obese patients can help to identify SMV and allow safer dissection.

Impact of preoperative body mass index and weight loss on morbidity and mortality following colorectal cancer-a retrospective cohort study

PURPOSE

Body weight and preoperative weight loss (WL) are controversially discussed as risk factors for postoperative morbidity and mortality in colorectal cancer surgery. The objective of this study is to determine whether body mass index (BMI) or WL is associated with a higher postoperative complication rate.

METHODS

In this retrospective cohort study, data analysis of 1241 consecutive patients undergoing colorectal cancer surgery in an 11-year period was performed. The main outcome measures were wound infections (WI), anastomotic leakages (AL), and in-house mortality.

RESULTS

A total of 697 (56%) patients with colon and 544 (44%) with rectum carcinoma underwent surgery. The rate of WI for each location increased with rising BMI. The threshold value was 28.8 kg/m2. Obese patients developed significantly more WI than normal-weight patients did following rectal resection (18.0% vs. 8.2%, p = 0.018). Patients with preoperative WL developed significantly more AL following colon resections than did patients without preoperative WL (6.2% vs. 2.5%, p = 0.046). In-house mortality was significantly higher in obese patients following colon resections than in overweight patients (4.3% vs. 0.4%, p = 0.012). Regression analysis with reference to postoperative in-house mortality revealed neither increased BMI nor WL as an independent risk factor.

CONCLUSIONS

Increased preoperative BMI is associated with a higher WI rate. AL rate after colon resection was significantly higher in patients showing preoperative WL. Preoperative BMI and WL are therefore risk factors for postoperative morbidity in this study. Nevertheless, this has to be further clarified by means of prospective studies. Trial registration DRKS00025359, 21.05.2021, retrospectively registered.

Risk factors for leak after omentopexy for duodenal ulcer perforations

AIMS

Duodenal ulcer perforations are frequently encountered but there is limited literature regarding risk factors for leak after omentopexy.

METHODOLOGY

The record of 100 patients of duodenal ulcer perforation undergoing omentopexy by open approach was prospectively maintained to identify any significant factors contributing towards leak.

RESULTS

Out of 100 patients undergoing omentopexy, 9 (9%) developed leak; when leak occurred, the mortality was very high (44.4%). Patients who developed leak (09) were compared against those who did not (91), and it was seen that seen that duration of symptoms before surgery (> 3 days), amount of intra-abdominal contamination (> 2 L), low body mass index (BMI < 19.35 kg/m²), serum creatinine (> 1.5 mg/dl), and deranged International Normalized Ratio (INR) were found to be significant on univariate analysis; however, multivariate analysis revealed only low BMI and high creatinine to be contributory towards leak.

CONCLUSION

Leak after omentopexy carries a high morbidity and mortality. Identification of risk factors may help in optimizing patients at risk and reduce the incidence of leak and its sequelae.

TRIAL REGISTRATION NUMBER

CTRI/2020/03/023798.

Risk Factors for Anastomotic Leak, Consideration for Proximal Diversion, and Appropriate Use of Drains

Anastomotic leaks are a major source of morbidity after colorectal surgery. There is a myriad of risk factors that may contribute to anastomotic leaks. These risk factors can be categorized as modifiable, nonmodifiable, and intraoperative factors. Identification of these risk factors allows for preoperative optimization that may minimize the risk of anastomotic leak. Knowledge of such high-risk features may also affect intraoperative decision-making regarding the creation of an anastomosis, consideration for proximal diversion, or placement of a drain. A thorough understanding of the interplay between risk factors, indications for proximal diversion, and utility of drain placement is imperative for colorectal surgeons.

Diagnosis of Anastomotic Leak

Anastomotic leaks after colorectal surgery is associated with increased morbidity and mortality. Understanding the impact of anastomotic leaks and their risk factors can help the surgeon avoid any modifiable pitfalls. The diagnosis of an anastomotic leak can be elusive but can be discerned by the patient's global clinical assessment, adjunctive laboratory data and radiological assessment. The use of inflammatory markers such as C-Reactive Protein and Procalcitonin have recently gained traction as harbingers for a leak. A CT scan and/or a water soluble contrast study can further elucidate the location and severity of a leak. Further intervention is then individualized on the spectrum of simple observation with resolution or surgical intervention.

Defining Anastomotic Leak and the Clinical Relevance of Leaks

Surgeons universally dread gastrointestinal anastomotic leaks, yet the precise definition is not widely agreed on despite international consensus guidelines. Likewise, leaks are not uniformly reported which makes comparisons across studies flawed. Leak rates range from 1 to 3% for ileocolonic, 0.5 to 18% for colorectal, and 5 to 19% for coloanal anastomoses. The sequelae of an anastomotic leak vary but generally correlate with the need for a change in clinical management, from minimal changes to the need for reoperation. Short- and long-term outcomes can be life-altering or life-threatening. Temporary or permanent stomas may be necessary and low pelvic anastomotic leaks may affect bowel function. For cancer patients, leaks can delay treatment and negatively affect oncologic outcomes. In Crohn's patients, leaks are associated with higher recurrence rates. In essence, the lack of agreement on the definition of an anastomotic leak inhibits meaningful understand of its epidemiology, prevention, and treatment.

Future incidence and mortality of colorectal carcinoma in the United States: an updated overview of risk factors and preventative measures

According to the Global Cancer Observatory (GLOBOCAN) 2020, colorectal carcinoma (CRC) was the second leading cause of cancer death globally. Current literature utilizes reported databases such as Surveillance, Epidemiology, and End Results (SEER) to better understand the epidemiology of CRC. The global cancer observatory’s “Cancer Tomorrow” data visualization tools was used to predict the future incidence and mortality of colorectal cancers until 2030 as a guided tool to look over ways to reduce incidence by controlling risk factors of CRC. The total number of CRC is expected to rise by 2030, with a percent change of 17.3%. The expected percent change in colon cancer is more than rectal cancer (19.8% vs. 11.6%). The estimated number of deaths secondary to CRC is expected to increase in 2030, an estimated percent change of 22.2%. The incidence and mortality rate was higher in men vs. women; however, the gap seems to be closing on trend analysis. Major risk factors for CRC include familial syndromes, family history, race, gender, obesity, diet, alcohol, and smoking. Risk can be reduced by exercise and dietary changes, fiber intake, vitamin D, calcium, and minerals. Individualized screening based on age, gender, and additional risk factors could be an option that needs further comparative data to propose a definitive benefit over established screening guidelines.

Does the body mass index impact lymph node yield for colorectal cancer resection, and does operative approach influence this: a review of bi-national colorectal cancer audit database

BACKGROUND

Operating on an obese patient is technically more challenging. This study aimed to determine whether there was any correlation between lymph node (LN) harvesting and patient's BMI, and how the operative approach influences this.

METHODS

A retrospective analysis of the bi-national colorectal cancer audit (BCCA) database from 2008 to 2018 was performed.

RESULTS

In the analysis of the correlation between operative approach and number of lymph nodes, data on 22 963 patients were analyzed. The operative approach did not lead to a significant difference in the number of lymph nodes yielded, except for proctocolectomy and low anterior resection where laparoscopic approach yielded greater lymph nodes than open approach. Linear regression of BMI and number of lymph nodes harvested for each operation based on 3986 patients showed that BMI largely does not impact the lymph node yield. The exception was open left hemicolectomy/sigmoid colectomy and laparoscopic high anterior resection, where a unit increase in BMI led to a reduction in the number of lymph nodes harvested. However, the regression coefficient and reduction in number of lymph nodes were low (r²  = 0.11, r²  = 0.0108 and 0.41, 0.18 lymph nodes).

CONCLUSION

In colorectal cancer operations, the number of lymph nodes removed is largely not impacted by the patient's body mass index, regardless of which operative approach is taken.

Robotic Intracorporeal Anastomosis

Robotic intracorporeal anastomosis is currently increasingly used for the performance of colorectal anastomosis. We describe the technical details for the proper performance of an iso- and anti-peristaltic anastomosis including the set up of the robotic platform and the performance of the anastomosis.

Obesity and anastomotic leak rates in colorectal cancer: a meta-analysis

PURPOSE

Anastomotic leak (AL) following colorectal cancer resection is associated with considerable morbidity and mortality with an impact on recurrence rates and survival. The impact of obesity on AL rates is debated. This meta-analysis aims to investigate the relationship between obesity and AL.

METHODS

A search was conducted of the PubMed/MEDLINE, and Web of Science databases and included studies were split into Western and Asian groups based on population-specific body mass index (BMI) ranges for obesity. A meta-analysis was performed to assess the impact of obesity on AL rate following colorectal cancer resection.

RESULTS

Two thousand three hundred and four articles were initially screened. Thirty-one studies totaling 32,953 patients were included. Patients with obesity had a statistically significant increase in AL rate in all Western and Asian study groups. However, this increase was only clinically significant in the rectal anastomotic subgroups-Western: 10.8% vs 8.4%, OR 1.57 (1.01-2.44) and Asian: 9.4% vs 7.4%, OR 1.58 (1.07-2.32).

CONCLUSIONS

The findings of this analysis confirm that obesity is a significant risk factor for anastomotic leak, particularly in rectal anastomoses. This effect is thought to be primarily mediated via technical difficulties of surgery although metabolic and immunological factors may also play a role. Obesity in patients undergoing restorative CRC resection should be discussed and considered as part of the pre-operative counselling.

Prophylactic Postoperative High Flow Nasal Oxygen Versus Conventional Oxygen Therapy in Obese Patients Undergoing Bariatric Surgery (OXYBAR Study): a Pilot Randomised Controlled Trial

BACKGROUND

Patients with obesity are predisposed to a reduction in end-expiratory lung volume (EELV) and atelectasis after anaesthesia. High flow nasal oxygen (HFNO) may increase EELV, reducing the likelihood of postoperative pulmonary complications (PPC). We conducted a pilot randomised controlled trial (RCT) of conventional oxygen therapy versus HFNO after bariatric surgery. The aim was to investigate the feasibility of using electrical impedance tomography (EIT) as a means of assessing respiratory mechanics and to inform the design of a definitive RCT.

METHODS

We performed a single-centre, parallel-group, pilot RCT. Adult patients with obesity undergoing elective bariatric surgery were eligible for inclusion. We excluded patients with a known contraindication to HFNO or with chronic lung disease.

RESULTS

Fifty patients were randomised in equal proportions. One patient crossed over from conventional O₂ to HFNO. Delta EELI was higher at 1 hour in patients receiving HFNO (mean difference = 831 Au (95% CI - 1636-3298), p = 0.5). Continuous EIT beyond 1 hour was poorly tolerated. At 6 hours, there were no differences in PaO₂/FiO₂ ratio or PaCO₂. Only one patient developed a PPC (in the HFNO group) by 6 weeks.

CONCLUSIONS

These data suggest that a large-scale RCT of HFNO after bariatric surgery in an 'all-comers' population is likely infeasible. While EIT was an effective means of assessing respiratory mechanics, it was impractical over time. Similarly, the infrequency of PPC precludes its use as a primary outcome. Future studies should focus on identifying patients at the greatest risk of PPC.

Impact of Excess Body Weight on Postsurgical Complications

BACKGROUND

Obesity is considered a risk factor for postoperative complications as it can limit exposure to the operation field, thereby significantly prolonging surgery time. Obesity-associated comorbidities, such as low-grade systemic inflammation, impaired functional status, and type 2 diabetes, are independent risk factors for impaired anastomotic wound healing and nonsurgical site infections. If obesity itself is an independent risk factor for surgical complications remains controversial, but the reason for this is largely unexplored.

SUMMARY

A MEDLINE literature search was performed using the terms: "obesity," "excess body weight," and "surgical complications." Out of 65,493 articles 432 meta-analyses were screened, of which 25 meta-analyses were on the subject. The vast majority of complex oncologic procedures in the field of visceral surgery have shown higher complication rates in obese patients. Meta-analyses from the last 10 to 15 years with high numbers of patients enrolled consistently have shown longer operation times, higher blood loss, longer hospital stay for colorectal procedures, oncologic upper gastrointestinal (GI) procedures, and pancreatic surgery. Interestingly, these negative effects seem not to affect the overall survival in oncologic patients, especially in esophageal resections. A selection bias in oncologic upper GI patients may have influenced the results with higher BMI in upper GI cancer to be a predictor for better nutritional and performance status.

KEY MESSAGES

Contrary to bariatric surgery, only limited evidence indicated that site and type of surgery, the approach to the abdominal cavity (laparoscopic vs. open), institutional factors, and the type of perioperative care such as ERAS protocols may play a role in determining postsurgical complications in obese patients. The initial question remains therefore partially unanswered. Large nationwide register-based studies are necessary to better understand which aspects of obesity and its related comorbidities define it as a risk factor for surgical complications.

Preoperative risk factors for major postoperative complications after complex gastrointestinal cancer surgery: A systematic review

Patients undergoing complex gastrointestinal surgery are at high risk of major postoperative complications (e.g., anastomotic leakage, sepsis), classified as Clavien-Dindo (CD) ≥ IIIa. Identification of preoperative risk factors can lead to the identification of high-risk patients. These risk factors can also be used to design personalized perioperative care. This systematic review focuses on the identification of these factors. The Medline and Embase databases were searched for prospective, retrospective cohort studies and randomized controlled trials investigating the effect of risk factors on the occurrence of major postoperative complications and/or mortality after complex gastrointestinal cancer surgery. Risk of bias was assessed using the Quality in Prognostic Studies tool. The level of evidence was graded based on the number of studies reporting a significant association between risk factors and major complications. A total of 207 eligible studies were retrieved, identifying 33 risk factors for major postoperative complications and 13 preoperative laboratory results associated with postoperative complications. The present systematic review provides a comprehensive overview of preoperative risk factors associated with major postoperative complications. A wide range of risk factors are amenable to actions in perioperative care and prehabilitation programs, which may lead to improved outcomes for high-risk patients. Additionally, the knowledge of this study is important for benchmarking surgical outcomes.

Obesity affects outcomes of pancreatoduodenectomy

BACKGROUND

Obesity is a major global health problem, and it has reached epidemic proportions worldwide. Therefore, surgeons will confront an increasingly larger proportion of obese candidates for pancreatoduodenectomy (PD) in the future. Several small retrospective studies have been conducted to evaluate the role of Body Mass Index (BMI) in postoperative surgical complications after PD, with conflicting results. The aim of this study was to use a large multi-institutional database to clarify the impact of different levels of obesity after PD.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database was queried for patients who underwent PD from 2014 to 2016. Patients were categorized in the following six BMI groups: <18.5 (Underweight), 18.5-24.9 (Normal Weight), 25-29.9 (Overweight), 30-34.9 (Class I obesity), 35-39.9 (Class II Obesity) and >40 (Class III Obesity). The primary outcomes of interest were 30-day mortality and morbidity after PD among the six BMI groups.

RESULTS

The final population consists of 10,316 patients. Class III is associated with higher risk of 30-day mortality (OR 2.56, 95% CI 1.25-5.25, p = 0.011), major complications (OR 2.23, 95% CI 1.54-3.22, p < 0.001), clinically relevant postoperative pancreatic fistula (OR 2.48, 95% CI 1.89-3.24, p < 0.001), surgical site infections (OR 2.06, 95% CI 1.61-2.65, p < 0.001) and wound dehiscence (OR 3.47, 95% CI 1.7-7.1, p < 0.001) in multivariable analysis.

CONCLUSIONS

In conclusion, our study shows that obesity is significantly associated with higher risk of postoperative complications in patients undergoing PD and patients with BMI≥40 have increased risk of mortality after PD.

Robotic versus laparoscopic anterior resections for rectal and rectosigmoid cancer: an institutional experience

INTRODUCTION

Colorectal surgery has evolved with the advent of laparoscopic techniques and now robotic-assisted surgery. There is significant literature supporting the use of laparoscopic techniques over open surgery with evidence of enhanced post-operative recovery, reduced use of opioids, smaller incisions and equivalent oncological outcomes. Robotic minimally invasive surgery addresses some of the limitations of laparoscopic surgery, providing surgical precision and improvements in perception and dexterity with a resulting decrease in tissue damage.

METHODS

We retrospectively reviewed the medical records of patients who underwent robotic-assisted anterior resection for cancer of the rectum or rectosigmoid junction in our institution since our robotic programme began in 2017. Patient demographics were identified via electronic databases and patient charts. A matched cohort of laparoscopic cases was identified.

RESULTS

A total of 51 consecutive robotic-assisted anterior resections were identified and case matched with laparoscopic resections for comparison. Robotic-assisted surgery was associated with a shorter length of stay (p = 0.04), reduced initial post-operative analgesia requirements (p < 0.01) and no significant difference in time to bowel movement or stoma functioning (p = 0.84). All patients had an R0 resection, and there was no statistical difference in lymph node yield between the groups (p = 0.14). Robotic surgery was associated with a longer operative duration (p < 0.001).

CONCLUSION

In this early experience, robotic surgery has proven feasible and safe and is comparable to laparoscopic surgery in terms of completeness of resection and recovery. As costs and operating times decline and as technology progresses, robotic surgery may one day replace traditional laparoscopic techniques.

Risk factors for surgical site infection after colorectal resection: a prospective single centre study. An analysis on 287 consecutive elective and urgent procedures within an institutional quality improvement project

AIM

To determine the incidence and to investigate risk factors for surgical site infections (SSIs) in a cohort of patients undergoing colorectal surgery.

MATERIAL & METHODS

Data from all consecutive patients operated at our department in an elective or in an urgent setting over a 4-month period were prospectively collected and analysed. The updated Centres for Disease Control and Prevention guidelines were used to define and to score SSIs during weekly meetings. Multivariate analysis was performed considering a list of 20 potential perioperative risk factors.

RESULTS

A total of 287 patients (mean age 56.9 ± 16.8 years, 51.2% male) were included. Thirty-five patients (12.2%) developed SSI. Independent risk factors for SSI were BMI <20 kg/m² (OR 3.70; p = .022), cancer (OR 0.33; p = .046), respiratory comorbidity (OR 3.15; p = .035), presence of a preoperative stoma (OR 3.74; p = .003), and operative time ≥3 hours (OR 2.93; p = .014).

CONCLUSION

Identified incidence and risk factors for the development of SSI after colorectal surgery were consistent with those already reported in the literature. The possibility to develop a validated prediction model for SSIs warrants further investigation, in order to target specific preventive measures on high-risk population.

Laparoscopic hepatectomy reduces postoperative complications and hospital stay in overweight and obese patients

BACKGROUND

Laparoscopic liver surgery is currently considered the standard of care for various liver malignancies. However, studies focusing on perioperative outcome after laparoscopic hepatectomy (LH) in overweight patients are still sparse and its benefit compared to open hepatectomy (OH) is a matter of debate.

AIM

To analyze postoperative outcomes in overweight [body mass index (BMI) over 25 kg/m²] and obese (BMI over 30 kg/m²) patients undergoing LH and compare postoperative outcome with patients undergoing OH.

METHODS

Perioperative data of 68 overweight (BMI over 25 kg/m²) including a subcohort of obese (BMI over 30 kg/m²) patients (n = 27) who underwent LH at our institution between 2015 and 2019 were retrospectively analyzed regarding surgical outcome and compared to an equal number of patients undergoing OH.

RESULTS

The mean BMI was 29.8 ± 4.9 kg/m² in the LH group and 29.7 ± 3.6 kg/m² in the OH group with major resections performed in 20.6% (LH) and 26.5% (OH) of cases, respectively. Operative time (194 ± 88 min vs 275 ± 131 min; P < 0.001) as well as intensive care (0.8 ± 0.7 d vs 1.1 ± 0.8 d; P = 0.031) and hospital stay (7.3 ± 3.6 d vs 15.7 ± 13.5 d; P < 0.001) were significant shorter in the LH group. Also, overall complications (20.6% vs 45.6%; P = 0.005) and major complications (1.5% vs 14.7%, P = 0.002) were observed less frequently after LH. An additional investigation analyzing the subgroup of obese patients who underwent LH (n = 27) and OH (n = 29) showed a shorter operative time (194 ± 81 min vs 260 ± 137 min; P = 0.009) and a reduced length of hospitalization (7.7 ± 4.3 d vs 17.2 ± 17 d; P < 0.001) but no difference in postoperative complications or overall cost.

CONCLUSION

LH is safe and cost-effective in overweight and obese patients. Furthermore, LH is significantly associated with fewer postoperative complications and reduced hospital stay compared to OH in these patients.

The assessment of perioperative risk factors of anastomotic leakage after intestinal surgeries; a prospective study

Background

Anastomotic leaks (AL) are among the most serious complications due to the substantial impact on the quality of life and mortality. Inspite of the advance in diagnostic tools such as laboratory tests and radiological adjuncts, only moderate improvement has been recorded in the rate of detected leaks. The purpose of the research was to assess the perioperative risk factors for AL.

Methods

This study was achieved at MUH and MIH/Egypt within the period between January 2016 and January 2019 for the candidates who underwent bowel anastomosis for small intestinal (except duodenal one) and colorectal pathology. The collected data were analyzed using SPSS of V-26.

Results

This study included 315 cases, among them, 27 cases (8.57%) developed AL. The percentage of covering stoma was significantly higher in the non-leakage group vs leakage one (24.3% vs 11.1% respectively). lower albumin, operative timing, perforation, and covering stoma were shown as significant risk factors for leakage, but with multivariate analysis for these factors, the emergency operation, and serum albumin level was the only independent risk factors that revealed the significance consequently (p = 0.043, p = 0.015). The analysis of different predictors of AL on the third day showed that the cut-off point in RR was 29 with 83% sensitivity and 92% specificity in prediction of leakage, the cut-off point in RR was 118 with 74% sensitivity and 87% specificity in prediction of leakage and the cut-off point in CRP was 184.7 with 82% sensitivity and 88% specificity in prediction of AL and all had statistically significant value.

Conclusions

The preoperative serum albumin level and the emergency operations are independent risk factors for anastomotic leakage. Moreover, leakage should be highly suspected in cases with rising respiratory rate, heart rate, and CRP levels.

Review of Colonic Anastomotic Leakage and Prevention Methods

Although surgeries involving anastomosis are relatively common, anastomotic leakages are potentially deadly complications of colorectal surgeries due to increased risk of morbidity and mortality. As a result of the potentially fatal effects of anastomotic leakages, a myriad of techniques and treatments have been developed to treat these unfortunate cases. In order to better understand the steps taken to treat this complication, we have created a composite review involving some of the current and best treatments for colonic anastomotic leakage that are available. The aim of this article is to present a background review of colonic anastomotic leakage, as well as current strategies to prevent and treat this condition, for a broader audience, including scientist, engineers, and especially biomedical engineers.

Obese patients and robotic colorectal surgery: systematic review and meta-analysis

BACKGROUND

Obesity is a major health problem, demonstrated to double the risk of colorectal cancer. The benefits of robotic colorectal surgery in obese patients remain largely unknown. This meta-analysis evaluated the clinical and pathological outcomes of robotic colorectal surgery in obese and non-obese patients.

METHODS

MEDLINE, Embase, Global Health, Healthcare Management Information Consortium (HMIC) and Midwives Information and Resources Service (MIDIRS) databases were searched on 1 August 2018 with no language restriction. Meta-analysis was performed according to PRISMA guidelines. Obese patients (BMI 30 kg/m2 or above) undergoing robotic colorectal cancer resections were compared with non-obese patients. Included outcome measures were: operative outcomes (duration of surgery, conversion to laparotomy, blood loss), postoperative complications, hospital length of stay and pathological outcomes (number of retrieved lymph nodes, positive circumferential resection margins and length of distal margin in rectal surgery).

RESULTS

A total of 131 full-text articles were reviewed, of which 12 met the inclusion criteria and were included in the final analysis. There were 3166 non-obese and 1420 obese patients. A longer duration of surgery was documented in obese compared with non-obese patients (weighted mean difference -21·99 (95 per cent c.i. -31·52 to -12·46) min; P < 0·001). Obese patients had a higher rate of conversion to laparotomy than non-obese patients (odds ratio 1·99, 95 per cent c.i. 1·54 to 2·56; P < 0·001). Blood loss, postoperative complications, length of hospital stay and pathological outcomes were not significantly different in obese and non-obese patients.

CONCLUSION

Robotic surgery in obese patients results in a significantly longer duration of surgery and higher conversion rates than in non-obese patients. Further studies should focus on better stratification of the obese population with colorectal disease as candidates for robotic procedures.

Impact of visceral obesity and sarcobesity on surgical outcomes and recovery after laparoscopic resection for colorectal cancer

BACKGROUND & AIMS

Studies analyzing the impact of visceral fat excess on surgical outcomes after resection for colorectal cancer (CRC) have yielded conflicting results. Visceral obesity (VO) and sarcobesity (SO) have been recently addressed as risk factors for poor short-term results while no data are available for recovery goals after surgery. No data are available on the protective effect of ERAS in VO and SO patients. The aim of this study was to assess clinical implications of computed tomography (CT) assessed VO and SO on surgical and recovery outcomes after minimally invasive resection for CRC before and after ERAS protocol implementation.

METHODS

Visceral adipose tissue (VAT) and skeletal muscle area (SMA) were retrospectively assessed using pre-operative CT studies of 261 patients who underwent laparoscopic resection for CRC between January 2012 and April 2019; ERAS protocol was adopted in 160 patients operated on after March 2014. Patients' surgical and recovery outcomes were compared according to BMI categories, VO and SO which was defined using the VAT/SMA ratio (Sarcobesity Index). Predictive factors for poor surgical and recovery outcomes were evaluated by univariate and multivariate analyses.

RESULTS

Of the 261 patients, 12.6% were BMI obese while 68.6% presented visceral obesity. BMI was not associated to any of the outcomes considered. No differences in intra-operative results were found except for a lower number of retrieved lymph nodes both in VO and SO patients. While VO showed no impact on post-operative course, SO resulted an independent risk factor for cardiac complications and prolonged post-operative ileus (PPOI) at logistic regression analysis. Furthermore, sarcobese patients showed delayed recovery after surgery. Patients enrolled in the ERAS protocol showed improved recovery outcomes for both VO and SO groups, although ERAS did not result to be a protective factor for cardiac complications and PPOI.

CONCLUSIONS

A high Sarcobesity Index is a risk factor for developing cardiac complications and PPOI after laparoscopic resection for CRC. A reduced number of lymph nodes retrieved is associated to VO and SO. These conditions should then be considered in clinical practice for the risk of down staging the N stage. Effect of VO and SO on recovery items after surgery should be further investigated. ERAS protocol application should be implemented to improve recovery outcomes in VO and SO patients undergoing laparoscopic colorectal resection.

Could Preoperative Unintended Weight Loss Predispose to Postoperative Thrombosis in Patients Undergoing Colorectal Cancer Surgery? An Analysis of the NSQIP Data

Objective: A significant portion of colorectal cancer patients lose weight preoperatively. Here we examine the influence of pre-operative significant weight loss on venous thromboembolism (VTE) risk and determine whether pre-operative BMI and albumin could influence VTE outcomes in patients who have lost significant weight prior to surgery.Methods: We conducted a retrospective cohort study using the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) and identified 103,455 colorectal cancer patients undergoing major surgery from 2008 to 2012. Patients were assigned to one of two groups based on whether they lost significant weight preoperatively or not. Simple and stepwise multiple logistic regressions were used to evaluate the association between pre-operative unintended weight loss and 30-days postoperative outcomes. The association between weight loss and postoperative thrombosis was further assessed across several strata.Results: The overall prevalence of pre-operative significant weight loss was 6.8%. Significant weight loss prior to surgery was significantly and independently associated with a higher risk of VTE (adjusted OR 1.23, 95% CI 1.06-1.44), mortality (adjusted OR 1.55, 95% CI 1.35-1.78), composite morbidity (adjusted OR 1.52, 95% CI 1.42-1.62), bleeding (adjusted OR 1.78, 95% CI 1.67-1.91) and return to operation room (adjusted OR 1.29, 95% CI 1.16-1.42). The effect of pre-operative significant weight loss on thromboembolic outcome was evident across patients with a BMI <18.5 kg/m², 18.5 < BMI < 24.99 and BMI >40kg/m².Conclusions: Significant weight loss and BMI both need to be measured preoperatively to stratify patients who are at a higher risk of VTE.

Outcomes of inflammatory bowel disease surgery in obese versus non-obese patients: a meta-analysis

BACKGROUND

Obesity is considered a risk factor for many chronic diseases and obese patients are often considered higher risk surgical candidates. The aim of this meta-analysis was to evaluate the outcomes of obese (body mass index ≥ 30 kg/m²) versus non-obese patients undergoing surgery for inflammatory bowel disease (IBD).

METHODS

PubMed, Scopus, and Embase libraries were searched up to March 2019 for studies comparing outcomes of obese with non-obese patients undergoing surgery for IBD. A meta-analysis was conducted using Review Manager software to create forest plots and calculate odds ratios and mean differences.

RESULTS

Four thousand three hundred and eleven patients from five observational studies were included. Obese patients were older at the time of surgery and more likely to have diabetes. Obese patients had longer operative times (MD 23.28, 95% CI 14.63-31.93, p < 0.001), higher intra-operative blood loss (MD 45.32, 95% CI 5.89-84.76, p = 0.02), longer length of stay (MD 0.90, 95% CI 0.60-1.20, p < 0.001), higher wound infection rates (OR 1.76, 95% CI 1.39-2.23, p < 0.001), and higher total postoperative complication rates (OR 1.33, 95% CI 1.04-1.70, p = 0.02).

CONCLUSIONS

Obesity is associated with significantly worse outcomes following IBD-specific surgery, including longer operative times, greater blood loss, longer length of stay, higher wound infection rates, and higher total postoperative complication rates. Clinicians should be mindful of these increased risks when counselling patients and consider weight reduction strategies where possible.

Pelvic fat volume reduction with preoperative very low energy diet (VLED): implications for rectal cancer surgery in the obese

BACKGROUND

Obese patients have higher complication rates after pelvic surgery. Laparoscopic rectal surgery may not be possible in the obese individual due to mesorectal, total pelvic and general visceral fat volumes. Very low energy diets reduce visceral fat but the changes within the pelvis and mesorectum are unknown. The aim of the present study was to quantify the proportion of fat lost from total pelvic and mesorectal fat with a very low energy diet (VLED) and define simple, accessible measurements that correlate with expected volume reduction.

METHODS

A study was conducted on proportion change in mesorectal and intrapelvic fat volumes in patients on a VLED prior to bariatric surgery at the Alfred Hospital in Melbourne. The VLED was a standardized 4-week meal replacement. Proportion change in mesorectal and intrapelvic fat volumes were measured. Patients had standardized pre-diet and post-diet magnetic resonance imaging (MRI) of the pelvis. Body mass index, weight and girth measures were obtained. Adipose quantification analysis was performed using Q-Fat.

RESULTS

Nine patients were included in this study, who were preparing for bariatric (not colorectal) surgery (5 females, median age 42 years, range 27-59 years) pre-protocol body mass index was 55.8 (range 39.5-60.6 kg/m²); median weight was 163 kg. Median mesorectal fat reduction was 29.9% (range 11.6-66.6%). Linear regression showed a relationship between the amount of mesorectal fat reduction and two variables: patient height and the distance from S1 to the posterior aspect of the rectum on MRI. The relationship predicted response to the diet (R² 67%, p = 0.040).

CONCLUSIONS

Very low energy diets result in a clinically significant reduction in mesorectal fat with a lesser change in total pelvic fat, suggesting that very low energy diets may be useful for preparation for pelvic surgery in the obese. The distance from S1 to the posterior rectum correlates well with mesorectal reduction, making this a valuable clinical tool when volumetric analysis is not possible. This analysis is limited to the quantification of the effect of the diet and cannot comment on the safety of this approach before pelvic cancer surgery.

Impact of Body Composition on Surgical Outcome in Rectal Cancer Patients, a Retrospective Cohort Study

BACKGROUND

Obesity is becoming a bigger health problem every year. Current research shows that the obesity-related metabolic problems are strongly associated with visceral fat and not subcutaneous fat. Visceral obesity (VO) is associated with a worse postoperative outcome in multiple fields of abdominal surgery. On the other hand, muscle mass is related to better postoperative outcome. In rectal cancer patients, we studied the influence of visceral obesity and muscle mass on postoperative complications.

METHODS

The visceral fat area (VFA) and skeletal muscle area (SMA) were determined on preoperative CT scans in 406 patients. The preoperative comorbidity, per-operative outcome and postoperative complications were extracted retrospectively from the patient files. VO was defined as a VFA > 100 cm². Correlations between body composition, postoperative complications and LOS were studied.

RESULTS

In our study, 67% of the patients were classified as visceral obese. Mean body mass index (BMI) was higher in the VO group (26.6 ± 3.5 vs 23.5 ± 2.8; p < 0.001). Visceral obese patients had a higher prevalence of cardiac comorbidity (29% vs 13% p = 0.001), hypertension (36% vs 20% p = 0.002) and diabetes mellitus (16% vs 5% p = 0.002). In addition, VO patients had more operative blood loss (431 vs 310 mL; p = 0.008), longer operating time (166 vs 149 min p = 0.003) and more wound infections (14% vs 8% p = 0.048). Visceral obesity was associated with more complications (OR: 1.63 p = 0.043) and longer LOS (risk estimate: 1.18 p = 0.009).

CONCLUSION

VO patients more often had a history of cardiac disease, hypertension and diabetes mellitus. Visceral obesity correlated with a worse outcome after surgery for rectal cancer.

Longer Operative Time and Intraoperative Blood Transfusion are Associated with Postoperative Anastomotic Leak after Lower Gastrointestinal Surgery

Anastomotic leak after lower gastrointestinal surgery is a complication with potential for high morbidity, mortality, and increased costs. A single-institution retrospective chart review was performed on all patients who underwent lower gastrointestinal surgery between June 2009 and June 2013. Fifty-seven variables were included in our analysis and their association with postoperative anastomotic leak was examined. Nine hundred fifty-two patients underwent 983 lower gastrointestinal anastomoses with an overall leak rate in this series of 6 per cent. Type of intestinal anastomosis created (P < 0.00005), operative indication (P < 0.015), operation performed (P < 0.014), intraoperative blood transfusion (P < 0.017), and intraoperative surgical drain placement (P < 0.022) were all predictive of anastomotic leak. Anastomotic leak rate increased by 1.3 times for every additional hour in the operating room after three hours. Both increasing operation time and intraoperative blood transfusions were associated with an increased rate of anastomotic leak. When operative time extends beyond three hours or in those cases were blood transfusions are given, surgeons should consider taking steps to minimize the risks of a potential anastomotic leak.

Relevante Nebenerkrankungen zu Notfallindikationen und Notfalloperationen in der Viszeral- und Allgemeinchirurgie

Die Adipositas ist eine über das Normalmaß hinausgehende Vermehrung des Körperfetts und wird über den Body-Mass- Index (BMI = kg/m) bestimmt. Ab einem BMI von 30 kg/m liegt definitionsgemäß eine Adipositas vor. Der Krankheitswert ergibt sich aus der Assoziation von Folgeerkrankungen, deren Risiko mit der Prävalenzdauer und dem Schweregrad der Adipositas ansteigt (Tab. 28.1). Dabei korreliert das kardiovaskuläre Risiko besonders mit dem Vorliegen einer viszeralen Adipositas (>88/102 cm Taillenumfang bei Frauen/ Männern). Die Prävalenz der Adipositas steigt in Deutschland kontinuierlich an. Derzeit ist knapp ein Viertel der deutschen Bevölkerung als adipös einzustufen.

Association of obesity with colonic findings in screening colonoscopy in a large population-based study

Background and aims

Obesity is associated with an increased incidence of and mortality from colorectal cancer (CRC). Screening colonoscopy seems particularly important for individuals with obesity. The aim of this study is to analyse the characteristics of screening colonoscopy in individuals with obesity.

Methods

We performed a cross-sectional analysis of records of 75,278 patients from a national colonoscopy screening programme in Poland. The database contained demographic data, colonoscopy results, self-reported data on weight and height, a standardized screenees' experience questionnaire and colorectal findings.

Results

Adenoma detection rate and advanced neoplasia detection rate increased significantly in groups of increasing body mass index (BMI). In subjects with morbid obesity, odds ratios for proximal adenoma and proximal advanced neoplasia were 1.69 (95% confidence interval (CI) 1.28-2.21) and 1.66 (95% CI 1.01-2.72), respectively, despite the fact that with BMI increasing over 30 the preparation for colonoscopy was worse. Moreover, caecal intubation increased with increasing BMI. Tolerance of colonoscopy was better and preparation for colonoscopy was less inconvenient in individuals with obesity.

Conclusions

Obesity and morbid obesity are associated with increased detection of colorectal precursor lesions and better performance of screening colonoscopy. Participation in screening colonoscopy should be emphasized among individuals with obesity, taking into account the burden of CRC in this population.

A Nomogram to Predict Anastomotic Leakage in Open Rectal Surgery-Hope or Hype?

BACKGROUND

Anastomotic leakage is the most dreaded complication after rectal resection and total mesorectal excision, leading to increased morbidity and mortality. Formation of a diverting ileostomy is generally performed to protect anastomotic healing. Identification of variables predicting anastomotic leakage might help to select patients who are under increased risk for the development of anastomotic leakage prior to surgery. The objective of this study was to assess the applicability of a nomogram as prognostic model for the occurrence of anastomotic leakage after rectal resection in a cohort of rectal cancer patients.

METHODS

Nine hundred seventy-two consecutive patients who underwent surgery for rectal cancer were retrospectively analyzed. Univariate and multivariable Cox regression analyses were used to determine independent risk factors associated with anastomotic leakage. Receiver operating characteristics (ROC) curve analysis was performed to calculate the sensitivity, specificity, and overall model correctness of a recently published nomogram and an adopted risk score based on the variables identified in this study as a predictive model.

RESULTS

Male sex (p = 0.042), obesity (p = 0.017), smoking (p = 0.012), postoperative bleeding (p = 0.024), and total protein level ≤ 5.6 g/dl (p = 0.007) were identified as independent risk factors for anastomotic leakage. The investigated nomogram and the adopted risk score failed to reach relevant areas under the ROC curve greater than 0.700 for the prediction of anastomotic leakage.

CONCLUSIONS

The proposed nomogram and the adopted risk score failed to reliably predict the occurrence of anastomotic leakage after rectal resection. Risk scores as prognostic models for the prediction of anastomotic leakage, independently of the study population, still need to be identified.

Does Robot Overcome Obesity-related Limitations of Minimally Invasive Rectal Surgery for Cancer?

BACKGROUND

Adoption of laparoscopic surgery for cancers requiring partial or total proctectomy has been slow due to difficulty of achieving oncologically adequate resection. Obesity is a factor complicating use and outcomes of laparoscopic technique for rectal surgery. Impact of obesity on the outcomes of robotic rectal surgery for cancer is not well defined. This study is designed to assess whether if the robotic technique has potential to overcome the limitations of obesity and to improve outcomes of minimally invasive rectal surgery for cancer.

PATIENTS AND METHODS

Patients undergoing robotic sphincter-saving radical resection with da Vinci Xi System between December 2014 and December 2016 were included. Patients were divided into 2 groups as obese and nonobese. Patient demographics, perioperative outcomes and short-term results were compared between the groups.

RESULTS

The study included 101 patients (30 were obese). Sex (female: 35 vs. 37%, P=0.89), American Society of Anesthesiologists score (2 vs. 2, P=0.41), number of patients undergoing neoadjuvant chemoradiation (39% vs. 23%, P=0.12) and history of prior abdominal surgery (28% vs. 23%, P=0.62) were comparable between the groups. Operative time was longer in the obese group (311 vs. 332 min. P=0.01). Overall complication rates (27% vs. 23%, P=0.72), length of hospital stay (6 vs. 7, P=0.10) and pathologic outcomes were similar between the groups. Conversion to laparoscopy was not required in any operation. Two nonobese patients required conversion to open surgery.

CONCLUSION

Robotic rectal surgery for cancer in obese patients is equally safe and effective as in nonobese patients. The new robotic platform can facilitate to overcome obesity-related limitations of rectal surgery.

High flow nasal oxygen after bariatric surgery (OXYBAR), prophylactic post-operative high flow nasal oxygen versus conventional oxygen therapy in obese patients undergoing bariatric surgery: study protocol for a randomised controlled pilot trial

BACKGROUND

The incidence of obesity is increasing worldwide. In selected individuals, bariatric surgery may offer a means of achieving long-term weight loss, improved health, and healthcare cost reduction. Physiological changes that occur because of obesity and general anaesthesia predispose to respiratory complications following bariatric surgery. The aim of this study is to determine whether post-operative high flow nasal oxygen therapy (HFNO2) improves respiratory function and reduces the incidence of post-operative pulmonary complications (PPCs) in comparison to conventional oxygen therapy in these patients.

METHOD

The OXYBAR study is a prospective, un-blinded, single centre, randomised, controlled pilot study. Patients with body mass index (BMI) > 30 kg/m2, undergoing laparoscopic bariatric surgery, will be randomised to receive either standard low flow oxygen therapy or HFNO2 in the post-operative period. The primary outcome measure is the change in end expiratory lung impedance (∆EELI) as measured by electrical impedance tomography (EIT). Secondary outcome measures include change in tidal volume (∆Vt), partial arterial pressure of oxygen/fraction of inspired oxygen (PaO2/FiO2) ratio, incidence of PPCs, hospital length of stay and measures of patient comfort.

DISCUSSION

We hypothesise that the post-operative administration of HFNO2 will increase EELI and therefore end expiratory lung volume (EELV) in obese patients. To our knowledge this is the first trial designed to assess the effects of HFNO2 on EELV in this population. We anticipate that data collected during this pilot study will inform a larger multicentre trial.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry (ANZCTR), ACTRN12617000694314 . Registered on 15 May 2017.

Postoperative bleeding risk prediction for patients undergoing colorectal surgery

BACKGROUND

There is limited consensus regarding risk factors for postoperative bleeding. The objective of this work was to investigate the capability of machine learning techniques in combination with practice-based longitudinal electronic medical record data for identifying potential new risk factors for postoperative bleeding and predicting patients at high risk of postoperative bleeding.

METHODS

A retrospective study was conducted for patients who underwent colorectal surgery 1998-2015 at a single tertiary referral center. Various predictors were extracted from electronic medical record. The outcome of interest was the occurrence of postoperative bleeding within 7 days of surgery. Logistic regression and gradient boosting machine models were trained. Area under the receiver operating curve and area under the precision recall curve were used to evaluate the performance to different models.

RESULTS

Of 13,399 cases undergoing colorectal resection, 1,680 (12.5%) experienced postoperative bleeding. A total of 299 variables were evaluated. Logistic regression and gradient boosting machine models returned an area under the receiver operating curve of 0.735 and 0.822 and area under the precision recall curve of 0.287 and 0.423, respectively. In addition to well-known risk factors for postoperative bleeding, nutrition (ranked third), weakness (ranked fifth), patient mobility (ranked sixth), and activity level (ranked eighth) were found to be novel predictors in the gradient boosting machine model based on permutation importance.

CONCLUSION

The study identified measures of functional capacity of patient as novel predictors of postoperative bleeding. The study found that risk of postoperative bleeding can be assessed, allowing for better use of human resources in addressing this important adverse event after surgery.

Commercial Very Low Energy Meal Replacements for Preoperative Weight Loss in Obese Patients: a Systematic Review

BACKGROUND

This systematic review assessed feasibility and effectiveness of preoperative meal replacements to improve surgical outcomes for obese patients.

METHODS

PRISMA guidelines were followed and electronic databases searched for articles between January 1990 and March 2015.

RESULTS

Fifteen studies (942 participants including 351 controls) were included, 13 studies (n = 750) in bariatric patients. Adverse effects and dropout rates were minimal. Ten out of 14 studies achieved 5-10 % total weight loss. Six of six studies reporting liver volume achieved 10 % reduction. Endpoints for perioperative risks and outcomes were too varied to support definitive risk benefit.

CONCLUSIONS

Commercial meal replacements are feasible, have minimal side effects and facilitate weight loss and liver shrinkage in free-living obese patients awaiting elective surgery. A reduction in surgical risk is unclear.

Outcomes according to body mass index following laparoscopic surgery in patients with colorectal cancer

Purpose:

Body mass index (BMI) may not be appropriate for different populations. Therefore, the World Health Organization (WHO) suggested 25 kg/m² as a measure of obesity for Asian populations. The purpose of this report was to compare the oncologic outcomes of laparoscopic colorectal resection with BMI classified from the WHO Asia-Pacific perspective.

Patients and Methods:

All patients underwent laparoscopic colorectal resection from September 2006 to March 2015 at a tertiary referral hospital. A total of 2408 patients were included and classified into four groups: underweight (n = 112, BMI <18.5 kg/m²), normal (n = 886, 18.5–22.9 kg/m²), pre-obese (n = 655, 23–24.9 kg/m²) and obese (n = 755, >25 kg/m²). Perioperative parameters and oncologic outcomes were analysed amongst groups.

Results:

Conversion rate was the highest in the underweight group (2.7%, P < 0.001), whereas the obese group had the fewest harvested lymph nodes (21.7, P < 0.001). Comparing oncologic outcomes except Stage IV, the underweight group was lowest for overall (P = 0.007) and cancer-specific survival (P = 0.002). The underweight group had the lowest proportion of national health insurance but the highest rate of medical care (P = 0.012).

Conclusion:

The obese group had the fewest harvested lymph nodes, whereas the underweight group had the highest estimated blood loss, conversion rate to open approaches and the poorest overall and cancer-specific survivals.

The safety and efficacy of laparoscopic hepatectomy in obese patients

BACKGROUND

Obesity is generally reported to increase the risk of surgical complications. There have been few reports of laparoscopic hepatectomy (LH) in obese patients. The purpose of this study was to compare the safety and efficacy of (1) LH versus open hepatectomy (OH) in obese patients and (2) LH in obese patients versus LH in non-obese patients.

METHODS

We introduced LH at our institution in April 2014. LH was performed in 63 obese patients and 108 non-obese patients from April 2014 to May 2017. OH was performed in 79 obese patients from January 2010 to May 2017. This study retrospectively compared the short-term outcomes of the LH obese group with those of the OH obese group and the LH non-obese group.

RESULTS

In patient characteristics, the LH obese group included a significantly higher percentage of patients with liver cirrhosis than the OH obese group. The LH obese group had fewer patients with a history of abdominal surgery but more with liver cirrhosis than the LH non-obese group. For short-term outcomes, the LH obese group had significantly less blood loss, fewer intraoperative transfusions, fewer positive surgical margins, and shorter postoperative hospital stays than the OH obese group. In contrast, only operation time was significantly different (longer) in the LH obese group than in the LH non-obese group. There were no significant differences in morbidity or mortality between the LH obese group and either the OH obese or the LH non-obese groups.

CONCLUSION

LH in obese patients is safe and effective.

Impact of radiofrequency energy on intraoperative outcomes of laparoscopic colectomy for cancer in obese patients

Nowadays laparoscopic approach is accepted as a valid alternative to open surgery for the treatment of colorectal cancer. Several studies consider this approach to be safe and feasible also in obese patients, even if dissection in these patients may require a longer operative time and involve higher blood loss. To facilitate laparoscopic approach, more difficult in these patients, several energy sources for laparoscopic dissection and sealing, has been adopted recently. The aim of this study is to investigate the possible intraoperative advantages of radiofrequency energy in terms of blood loss and operative time in obese patients undergoing laparoscopic resection for cancer. All patients who underwent laparoscopic surgery for colorectal cancer from January 2010 to December 2015 were registered in a prospective database. Patients with a body mass index BMI (kg/m²) ≥30 were defined as obese, and patients with a BMI (kg/m²) <30 were defined as non-obese. All 136 obese patients observed were divided retrospectively into 2 groups according to the devices used for dissection: 83 patients (Historical group: B) on whom dissection and coagulation were performed using other energy sources (monopolar electrocautery scissors, bipolar electrical energy, ultrasonic coagulating shears) and 53 patients who were treated with electrothermal bipolar vessel sealing (Caiman group: A). In group A, the Laparoscopic Caiman 5 (Aesculap AG, Tuttlingen, Germany) was the only instrument employed in the whole procedure. The study examined only three types of operation: right colectomy (RC), left colectomy (LC), and anterior resection (AR). Preoperative data were similar for RC, LC, and AR in both groups (A and B). The mean operative time was statistically shorter in the Caiman group than in the Historical group [104 vs 124 min (p 0.004), 116 vs 140 min (p 0.004), and 125 vs 151 min (p 0.003) for RC, LC, and AR between group A and B, respectively]. Also intraoperative blood loss results significantly lower in the Caiman group than in the historical one [52 ml vs 93 for RC (p 0.003); 65 vs 120 ml for LC (p 0.001); 93 vs 145 ml for AR (p 0.002) between group A and B, respectively]. No intraoperative complications were recorded in either group. The mean conversion rate was 4.4% (6 patients). There were no statistical differences in intensive care unit (ICU) stay, functional outcomes, mean hospital stay and overall morbidity rate between the two groups. There was no mortality in either group. The use of the Caiman EBVS instrument shows significant advantages with respect to a small number of intraoperative parameters. We can conclude that use of this radiofrequency device, in the laparoscopic approach, offers advantages in terms of lower intraoperative blood loss and shorter operative time in obese patients with colorectal cancer.

A perioperative care map improves outcomes in patients with morbid obesity undergoing major surgery

BACKGROUND

The surgical management of patients with morbid obesity (body mass index ≥ 40) is notable for a relatively high risk of complications. To address this problem, a perioperative care map was developed using precautions and best practices commonly employed in bariatric surgery. It requires additional medical assessments, sleep apnea surveillance, more stringent guidelines for anesthetic management, and readily available bariatric operating room equipment, among other items. This care map was implemented in 2013 at 4 major urban teaching hospitals for use in patients undergoing all types of nonambulatory surgery with a body mass index greater than 40 kg/m². The impact on patient outcomes was evaluated.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program database was used to compare 30-day outcomes of morbidly obese patients before the year 2013 and after the years 2015 care-map implementation. In addition, trends in 30-day outcomes for morbidly obese patients were compared with those for non-obese patients.

RESULTS

Morbidly obese patients, between 2013 and 2015, saw an adjusted decrease in the rate of unplanned return to the operating room (OR = 0.49; P = .039), unplanned readmission (OR = 0.57; P = .006), total duration of stay (-0.87 days; P = .009), and postoperative duration of stay (-0.69 days; P = .007). Of these, total duration of stay (-0.86 days; P = .015), and postoperative duration of stay (-0.69 days; P = .012) improved significantly more for morbidly obese patients than for nonmorbidly obese patients.

CONCLUSION

Outcomes in morbidly obese patients improved from 2013 to 2015. Implementation of a perioperative care map may have contributed to these improvements. The care map should be further investigated and considered for more widespread use.

Oncologic and Functional Hazards of Obesity Among Patients With Locally Advanced Rectal Cancer Following Neoadjuvant Chemoradiation Therapy

OBJECTIVE

Obesity is a major health concern and risk factor for colorectal cancer that may also impact cancer treatment and outcomes. Rectal cancer response to chemoradiotherapy (CXRT) is associated with long-term survival and sphincter preservation. The purpose of this study was to evaluate the impact of obesity on treatment outcomes after neoadjuvant CXRT for rectal cancer.

METHODS

A retrospective cohort study of patients diagnosed (1993 to 2010) with cT3-4 or cN+ (by endorectal ultrasound, computed tomography, or magnetic resonance imaging) rectal carcinoma and treated with CXRT and total mesorectal excision was performed. Patients were classified as obese (body mass index ≥30 kg/m) or nonobese (body mass index <30 kg/m), and by response to CXRT: complete (pCR) or incomplete (pIR). Associations between obesity, tumor response, and sphincter preservation were evaluated using multivariate logistic regression analysis and survival outcomes by Cox regression.

RESULTS

A total of 753 patients met criteria and 28.7% (n=216) patients were obese. Obese and nonobese groups did not differ in age, sex, tumor location, grade, or number of examined lymph nodes. However, obesity was associated with a lower rate of pCR (ORmulti=0.60; 95% confidence interval, 0.38-0.94; P=0.04) and among mid to low rectal cancer patients, a lower rate of sphincter preservation (ORmulti=0.67; 95% confidence interval, 0.45-0.99). Among both obese and nonobese patients, CR was associated with more favorable recurrence-free survival than pIR.

CONCLUSIONS

Considering the increasing obesity prevalence and its association with CXRT response, oncologic outcomes, and sphincter preservation, further study is needed regarding the impact of obesity on neoadjuvant treatment response. Moreover, obesity should be targeted as a modifiable risk factor for adverse outcomes following multimodality treatment for rectal cancer.

Impact of obesity on short and long term results following a pancreatico-duodenectomy

BACKGROUND

The impact of obesity on short and long term outcomes following a pancreatico-duodenectomy (PD) is still unclear and needs further clarification.

METHODS

Demographic, operative and outcomes data in 524 patients undergoing PD were analysed.

RESULTS

Ninety-seven patients (18.5%) had BMI greater than or equal to 30 kg/m² (group A) and 427 patients (81.5%) had BMI less than 30 kg/m² (group B). Group A had a significantly greater operative duration, (375 vs 360 min, p = 0.024) and a higher intra-operative blood loss, (660 vs 500 ml, p = 0.005). Post-operative pancreatic fistula (POPF) were more common in Group A (28.9% vs 16.2%, p = 0.006), this difference was also observed when considering only major POPF (Grade B and C) (16.5% vs 8.0%, p = 0.020). Intra-abdominal collections were higher in Group A, 28.9% compared to 19.0% in Group B (p = 0.037). On multivariate analysis BMI (OR 2.006; 95% CI 1.147-4.985, p = 0.040), small pancreatic duct (OR 2.755; 95% CI 1.589-2.968, p = 0.026) and soft pancreas (OR 2.289; 95% CI 1.126-3.665, p = 0.040) were found to be independent factors for POPF. The median survival for adenocarcinomas was 20 months in Group A and 22 months in Group B, (p = 0.109).

CONCLUSION

Patients with BMI ≥ 30 are at an increased risk of developing pancreatic fistula following PD. Obesity does not appear to have an impact on long term outcomes in patients undergoing a PD for adenocarcinomas.

Body Mass Index Significantly Impacts Outcomes of Colorectal Surgery

There are limited data regarding the association between body mass index (BMI) and colorectal surgery outcomes. We sought to evaluate the effect of BMI on short-term surgical outcomes in colon and rectal surgery patients in the United States. The American College of Surgeons National Surgery Quality Improvement Project database was used to identify all patients who underwent colon or rectal resection from 2005 to 2013. Multivariate regression analysis was used to assess the independent effect of BMI on outcomes. A total of 206,360 patients underwent colorectal resection during the study period. Of these, 3.2 per cent of patients were underweight (BMI < 18.5), 23.8 per cent patients were normal weight (18.5 ≤, BMI < 25), 26.5 per cent were overweight (25 ≤, BMI < 30), 25.2 per cent were obese (30 ≤, BMI < 40), and 5.3 per cent were morbidly obese (BMI ≥ 40). Underweight patients had longer length of stay (confidence interval: 2.70–3.49, P < 0.001) and higher mortality (adjusted odds ratio: 1.45, P < 0.01) compared with patients with a normal BMI. Morbidly obese patients had the highest overall morbidity rate compared with normal BMI patients (adjusted odds ratio: 1.53, confidence interval: 1.42–1.64, P < 0.01). BMI is associated with outcomes in colon and rectal surgery patients. Underweight and morbidly obese patients have a significantly increased risk of postsurgical complications compared with those with normal BMI.