Impact of body constitution on complications following pancreaticoduodenectomy: A retrospective cohort study

Preoperative body composition measured by bioelectrical impedance analysis can predict pancreatic fistula after pancreatic surgery

BACKGROUND

Postoperative pancreatic fistula (POPF) remains one of the most severe complications after pancreatic surgery. The methods for predicting pancreatic fistula are limited. We aimed to investigate the predictive value of body composition parameters measured by preoperative bioelectrical impedance analysis (BIA) on the development of POPF.

METHODS

A total of 168 consecutive patients undergoing pancreatic surgery from March 2022 to December 2022 at our institution were included in the study and randomly assigned at a 3:2 ratio to the training group and the validation group. All data, including previously reported risk factors for POPF and parameters measured by BIA, were collected. Risk factors were analyzed by univariable and multivariable logistic regression analysis. A prediction model was established to predict the development of POPF based on these parameters.

RESULTS

POPF occurred in 41 of 168 (24.4%) patients. In the training group of 101 enrolled patients, visceral fat area (VFA) (odds ratio [OR] = 1.077, P = 0.001) and fat mass index (FMI) (OR = 0.628, P = 0.027) were found to be independently associated with POPF according to multivariable analysis. A prediction model including VFA and FMI was established to predict the development of POPF with an area under the receiver operating characteristic curve (AUC) of 0.753. The efficacy of the prediction model was also confirmed in the internal validation group (AUC 0.785, 95% CI 0.659-0.911).

CONCLUSIONS

Preoperative assessment of body fat distribution by BIA can predict the risk of POPF after pancreatic surgery.

The Impact of Body Mass Index on Multiple Complications, Respiratory Complications, Failure to Rescue and In-hospital Mortality After Laparoscopic Pancreaticoduodenectomy: A Single-Center Retrospective Study

Background: Pancreaticoduodenectomy serves as the standard surgical treatment for periampullary tumors. Previous studies have suggested that high body mass index (BMI) is associated with an unfavorable prognosis following laparoscopic pancreaticoduodenectomy (LPD). However, the relationship between low BMI and postoperative complications remains unclear. Materials and Methods: A retrospective analysis of clinical data from 1130 patients who underwent LPD between April 2014 and December 2022 was conducted. Multivariate regression and restricted cubic spline analyses were utilized to explore the correlations between BMI and short-term outcomes, with adjustments for potential confounders. Results: Multivariable logistic regression revealed that overweight, obese, or severely underweight patients had an elevated risk of postoperative pancreatic fistula (POPF) compared to those with a normal BMI. Moreover, obesity was significantly correlated with a higher proportion of "failure to rescue." BMI exhibited a J-shaped relationship with respiratory complications and in-hospital mortality, a W-shaped relationship with multiple complications and anastomotic leakage (pancreatic fistula), and a U-shaped association with "failure to rescue" rates. The lowest risk was observed at BMI levels of 20 and 25 kg/m2 for multiple complications and pancreatic fistula, respectively. Conclusion: Both high and low BMI are identified as risk factors for the occurrence of postoperative POPF and in-hospital mortality following LPD. Notably, patients with higher BMI and severe underweight conditions are associated with an increased likelihood of "failure to rescue."

Preoperative ultrasound radiomics for predicting clinically relevant postoperative pancreatic fistula after pancreatectomy

OBJECTIVES

To evaluate the efficacy of the radiomics model based on preoperative B-mode ultrasound (BMUS) and shear wave elastography (SWE) for predicting the occurrence of clinically relevant-postoperative pancreatic fistula (CR-POPF).

METHODS

Patients who were scheduled to undergo pancreatectomy were prospectively enrolled and received ultrasound assessment within one week before surgery. The risk factors of POPF (grades B and grades C) were analyzed. Preoperative BMUS images, SWE values of pancreatic lesions and surrounding parenchyma were used to build preoperative prediction radiomics models. Radiomic signatures were extracted and constructed using a minimal Redundancy Maximal Relevance (mRMR) algorithm and an L1 penalized logistic regression. A combined model was built using multivariate regression which incorporated radiomics signatures and clinical data.

RESULTS

From January 2020 to November 2021, a total of 147 patients (85 distal pancreatectomies and 62 pancreaticoduodenectomies) were enrolled. During the three-week follow-up after pancreatectomy, the incidence rates of grade B/C POPF were 28.6% (42/147). Radiomic signatures constructed from BMUS of pancreas parenchymal regions (panRS) achieved an area under the receiver operating characteristic curve (AUC) of 0.75, accuracy of 68.7%, sensitivity of 85.7 %, and specificity of 61.9 % in preoperative noninvasive prediction of CR-POPF. The AUC of the radiomics model increased to 0.81 when panRS was used for the prediction of CR-POPF after pancreaticoduodenectomy.

CONCLUSIONS

Radiomics model based on ultrasound images was potentially useful for predicting CR-POPF. Patients with high-risk factors should be closely monitored when postoperation.

Predictive Factors for Delayed Gastric Emptying After Pancreatoduodenectomy: A Swedish National Registry-Based Study

BACKGROUND

Delayed gastric emptying (DGE) is a common complication after pancreatoduodenectomy (PD). DGE causes prolonged hospital stay and a decrease in quality of life. This study analyzes predictive factors for development of DGE after PD, also in the absence of surgical complications.

METHOD

Data from the Swedish National Pancreatic Cancer Registry for patients undergoing standard and pylorus preserving open PD from January 2010 until June 30, 2018, were collected. Data were analyzed in two groups, no DGE and DGE. A subgroup of patients with DGE but without surgical complications was compared to patients without DGE or any other surgical complication.

RESULTS

In total, 2503 patients were included, of which 470 (19%) had DGE. In the DGE group, 238 had other coexisting surgical complications and 232 had not. Postoperative pancreatic fistula (OR = 4.22, p < 0.001), surgical infection (OR = 1.44, p = 0.013), heart disease (OR = 1.32, p = 0.023) and medical complications (OR = 1.35, p = 0.025) increased the risk for DGE. A standard PD compared with pylorus preserving resection (OR = 1.69, p = 0.001) and a reconstruction with a pancreaticojejunostomy compared with a pancreaticogastrostomy (OR = 1.83, p < 0.001) increased the risk. For patients without surgical complications, a standard PD and reconstruction with pancreaticojejunostomy still increased the risk for DGE.

CONCLUSION

DGE is more common after standard PD compared to pylorus preserving PD and after reconstruction with PJ compared to PG in this national cohort, both in the presence of other surgical complications as well as in the absence of other complications.

Hyperglycemia and insulin infusion in pancreatoduodenectomy: a prospective cohort study on feasibility and impact on complications

BACKGROUND

Hyperglycemia is a risk factor for postoperative complications but its impact on outcome after pancreatoduodenectomy (PD) is scarcely studied. This prospective cohort study aimed to assess the effect of continuous insulin infusion on postoperative complications and blood glucose, as well as to evaluate the impact of hyperglycemia on complications, after PD.

MATERIALS AND METHODS

One hundred patients planned for PD at Skåne University Hospital, Sweden were prospectively included for perioperative continuous insulin infusion and a historic cohort of 100 patients was included retrospectively. Median blood glucose levels were calculated and data on complications were analyzed and compared between the historic cohort and the intervention group as well as between normo- and hyperglycemic patients.

RESULTS

Median glucose levels were significantly lower in the intervention group compared to the historic cohort up to 30 days postoperatively (median glucose 8.5 mmol/l (interquartile range 6.4-11) vs. 9.1 mmol/l (interquartile range 6.8-17) ( P =0.007)). No significant differences in complication rates were recorded between these two groups. The incidence of complications classified as Clavien ≥3 was higher in hyperglycemic patients (100 vs. 27%, P =0.024). Among hyperglycemic patients the prevalence of preoperative diabetes was higher compared to normoglycemic patients (52 vs.12%, P <0.001). In patients with a known diagnosis of diabetes, a trend, although not statistically significant, towards a lower incidence of postoperative pancreatic fistula grade B and C, as well as postpancreatectomy hemorrhage grade B and C, was seen compared to those without preoperative diabetes (6.8 vs. 14%, P =0.231 and 2.3 vs. 7.0%, P =0.238, respectively).

CONCLUSION

Insulin infusion in the early postoperative phase after PD is feasible in a non-ICU setting and significantly decreased blood glucose levels. The influence on complications was limited. Preoperative diabetes was a significant predictor of postoperative hyperglycemia and was associated with a lower incidence of clinically significant postoperative pancreatic fistula.

The visceral pancreatic neck anterior distance may be an effective parameter to predict post-pancreaticoduodenectomy clinically relevant postoperative pancreatic fistula

Background

The clinically relevant postoperative pancreatic fistula (CR-POPF) is significantly correlated with a high post-pancreaticoduodenectomy (PD) mortality rate. Several studies have reported an association between visceral obesity and CR-POPF. Nevertheless, there are many technical difficulties and controversies in the measurement of visceral fat. The aim of this research was to determine whether the visceral pancreatic neck anterior distance (V-PNAD) was a credible predictor for CR-POPF.

Methods

We retrospectively analyzed the data of 216 patients who underwent PD in our center between January 2016 and August 2021. The correlation of patients' demographic information, imaging variables, and intraoperative data with CR-POPF was assessed. Furthermore, areas under the receiver operating characteristic curves for six distances (abdominal thickness, visceral thickness, abdominal width, visceral width, abdominal PNAD, V-PNAD) were used to identify the best imaging distance to predict POPF.

Results

In the multivariate logistic analysis, V-PNAD (P < 0.01) was the most significant risk factor for CR-POPF after PD. Males with a V-PNAD >3.97 cm or females with a V-PNAD >3.66 cm were included into the high-risk group. The high-risk group had a higher prevalence of CR-POPF (6.5% vs. 45.1%, P < 0.001), intraperitoneal infection (1.9% vs. 23.9%, P < 0.001), pulmonary infection (3.7% vs. 14.1%, P = 0.012), pleural effusion (17.8% vs. 33.8%, P = 0.014), and ascites (22.4% vs. 40.8%, P = 0.009) than the low-risk group.

Conclusion

Of all imaging distances, V-PNAD may be the most effective predictor of CR-POPF. Moreover, high-risk patients (males, V-PNAD >3.97 cm; females, V-PNAD >3.66 cm) have a high incidence of CR-POPF and poor short-term post-PD prognosis. Therefore, surgeons should perform PD carefully and take adequate preventive measures to reduce the incidence of pancreatic fistula when the patient has a high V-PNAD.

External validation of postoperative pancreatic fistula prediction scores in pancreatoduodenectomy: a systematic review and meta-analysis

BACKGROUND

Multiple risk scores claim to predict the probability of postoperative pancreatic fistula (POPF) after pancreatoduodenectomy. It is unclear which scores have undergone external validation and are the most accurate. The aim of this study was to identify risk scores for POPF, and assess the clinical validity of these scores.

METHODS

Areas under receiving operator characteristic curve (AUROCs) were extracted from studies that performed external validation of POPF risk scores. These were pooled for each risk score, using intercept-only random-effects meta-regression models.

RESULTS

Systematic review identified 34 risk scores, of which six had been subjected to external validation, and so included in the meta-analysis, (Tokyo (N=2 validation studies), Birmingham (N=5), FRS (N=19), a-FRS (N=12), m-FRS (N=3) and ua-FRS (N=3) scores). Overall predictive accuracies were similar for all six scores, with pooled AUROCs of 0.61, 0.70, 0.71, 0.70, 0.70 and 0.72, respectively. Considerably heterogeneity was observed, with I2 statistics ranging from 52.1-88.6%.

CONCLUSION

Most risk scores lack external validation; where this was performed, risk scores were found to have limited predictive accuracy. . Consensus is needed for which score to use in clinical practice. Due to the limited predictive accuracy, future studies to derive a more accurate risk score are warranted.

Preferential Mobilization of Colonic Hepatic Flexure Facilitates Pancreaticoduodenectomy Procedures

BACKGROUND

Several studies recommend that colonic hepatic flexure (CHF) should be mobilized preliminarily in minimally invasive pancreaticoduodenectomy (PD). However, there are little data to support that preferential mobilization of the CHF can positively affect the perioperative events of PD. We aimed to assess the effect of preferential mobilization of the CHF in PD.

METHODS

A retrospective cohort study of patients who underwent PD was performed between 2016 and 2019. Clinical characteristics, operative data, and postoperative surgical complications were recorded.

RESULTS

The study included 668 patients; 486 patients underwent open pancreaticoduodenectomy (OPD) and 182 patients underwent laparoscopic pancreaticoduodenectomy (LPD). Patients were divided into CHF-M (OPD, n=129; LPD, n=95) and conventional (OPD, n=357; LPD, n=87) groups according to preferential CHF mobilization. There were no differences between the groups regarding most demographics. Within patients who underwent OPD, decreased estimated blood loss (EBL) (251.2±146.4 vs. 307.3±173.5 mL, P<0.05) was observed in CHF-M group. Within patients who underwent LPD, operative time (328.7±66.3 vs. 406.5±85.5 min, P<0.001), EBL (166.8±96.4 vs. 271.8±130.7 mL, P<0.001), the incidence of clinically relevant pancreaticfistula (7.4% vs. 23.0%, P<0.05), and length of stay (12.3±5.1 vs. 16.0±7.4 d, P<0.05) were decreased in CHF-M group. Moreover, patients with high body mass index who underwent LPD showed more significant differences in operative time (336.0±67.7 vs. 431.9±79.1, P<0.001) and EBL (179.6±97.8 vs. 278.2±135.6, P<0.001) between groups.

CONCLUSION

We first demonstrated that preferential mobilization of the CHF can facilitate PD. The patients who underwent minimally invasive surgery and the patients with high body mass index may benefit more from this technique.

Systematic review and meta-analysis of risk factors of postoperative pancreatic fistula after distal pancreatectomy in the era of 2016 International Study Group pancreatic fistula definition

BACKGROUND

Risk factors for the development of clinically relevant POPF (CR-POPF) following distal pancreatectomy (DP) need clarification particularly following the 2016 International Study Group of Pancreatic Fistula (ISGPF) definition.

METHODS

A systemic search of MEDLINE, Pubmed, Scopus, and EMBASE were conducted using the PRISMA framework. Studies were evaluated for risk factors for the development CR-POPF after DP using the 2016 ISGPF definition. Further subgroup analysis was undertaken on studies ≥10 patients in exposed and non-exposed subgroups.

RESULTS

Forty-three studies with 8864 patients were included in the meta-analysis. The weighted rate of CR-POPF was 20.4% (95%-CI: 17.7-23.4%). Smoking (OR 1.29, 95%-CI: 1.08-1.53, p = 0.02) and open DP (OR 1.43, 95%-CI: 1.02-2.01, p = 0.04) were found to be significant risk factors of CR-POPF. Diabetes (OR 0.81, 95%-CI: 0.68-0.95, p = 0.02) was a significant protective factor against CR-POPF. Substantial heterogeneity was observed in the comparisons of pancreatic texture and body mass index. Seventeen risk factors achieved significance in a univariate or multivariate comparison as reported by individual studies in the narrative synthesis, however, they remain difficult to interpret as statistically significant comparisons were not uniform.

CONCLUSION

This meta-analysis found smoking and open DP to be risk factors and diabetes to be protective factor of CR-POPF in the era of 2016 ISGPF definition.

The impact of obesity and severe obesity on postoperative outcomes after pancreatoduodenectomy

BACKGROUND

The impact of obesity on postoperative outcomes after pancreatoduodenectomy remains insufficiently studied.

METHODS

All pancreatoduodenectomy patients were abstracted from the 2014 to 2018 American College of Surgeons National Surgical Quality Improvement Program data sets and were stratified into the following 3 body mass index categories: non-obese (body mass index 18.5-29.9), class 1/2 obesity (body mass index 30-39.9), and class 3 severe obesity (body mass index ≥ 40). Analyses tested associations between patient factors and four 30-day postoperative outcomes: mortality, composite morbidity, delayed gastric emptying, and postoperative pancreatic fistula. Multivariable logistic regression models tested independent associations between patient factors and these 4 outcome measures.

RESULTS

A total of 16,823 patients were included in the study: 12,234 (72.7%) non-obese, 4,030 (24%) obese, and 559 (3.3%) with severe obesity. Bivariable analyses demonstrated significant associations between obesity, severe obesity, and greater proportions of numerous preoperative comorbidities as well as a greater likelihood of postoperative complications, including postoperative pancreatic fistula, delayed gastric emptying, composite morbidity, and mortality (all P ≤ .001). After adjusting for significant covariates, obesity was independently associated with postoperative pancreatic fistula (odds ratio 1.49, 95% confidence interval: 1.33-1.67, P < .001), delayed gastric emptying (odds ratio 1.16, 95% confidence interval: 1.05-1.28, P = .004), composite morbidity (odds ratio 1.28, 95% confidence interval: 1.18-1.38, P < .001), and mortality (odds ratio 1.79, 95% confidence interval: 1.36-2.36, P < .001).

CONCLUSION

Obesity and severe obesity are significantly associated with worse short-term outcomes after pancreatoduodenectomy. Preoperative considerations, such as weight management strategies during individualized treatment planning, could improve outcomes in this population.

Impact of body mass index on the early experience of robotic pancreaticoduodenectomy

Obesity increases surgical morbidity and mortality in open pancreaticoduodenectomy (OPD). Its influence on robotic pancreaticoduodenectomy (RPD) remains uncertain. This study aimed to investigate the impact of body mass index (BMI) on the early experience of RPD. Between June 2015 and April 2020, 68 consecutive RPDs were performed at the National Cheng Kung University Hospital. The patients were categorized as normal-weight (BMI < 23 kg/m²), overweight (BMI = 23–27.5 kg/m²), and obese (BMI > 27.5 kg/m²) according to the definition of obesity in Asian people from the World Health Organization expert consultation. Preoperative characteristics, operative details, and postoperative outcomes were prospectively collected. The cumulative sum was used to assess the learning curves. The average age of the patients was 64.8 ± 11.7 years with an average BMI of 24.6 ± 3.7 kg/m² (23 normal-weight, 29 overweight, and 16 obese patients). Eighteen patients were required to overcome the learning curve. The overall complication rate was 51.5%, and the major complication rate (Clavien grade ≥ III) was 19.1%. The normal-weight group showed the most favorable outcomes. The blood loss, major complication rate, peripancreatic fluid collection rate, and conversion rate were higher in the obese group than in the non-obese group. There were no differences in the operative time, clinically relevant postoperative pancreatic fistula, postoperative hemorrhage, delayed gastric emptying, bile leak, wound infection, reoperation, hospital stay, and readmission rate between the obese and non-obese groups. Multivariate analysis showed obesity as the only independent factor for major complications (OR: 5.983, CI: 1.394–25.682, p = 0.001), indicating that obesity should be considered as a surgical risk factor during the implementation of RPD.

A deep pancreas is a novel predictor of pancreatic fistula after pancreaticoduodenectomy in patients with a nondilated main pancreatic duct

BACKGROUND

We investigated the risk factors for clinically relevant postoperative pancreatic fistula after pancreaticoduodenectomy in patients with a nondilated main pancreatic duct.

METHODS

We investigated a total of 354 patients who underwent pancreaticoduodenectomy. The diameter of the main pancreatic duct, the shortest distance from the body surface to the pancreas (the pancreatic depth), and the computed tomography attenuation index (the difference between the pancreatic and splenic computed tomography attenuation) were measured in preoperative computed tomography.

RESULTS

One hundred eighty-one (51.1%) patients had a nondilated main pancreatic duct, and 50 (27.6%) of the 181 patients with a nondilated main pancreatic duct developed a clinically relevant postoperative pancreatic fistula. Univariate analyses revealed that the calculated body mass index (≥21.8 kg/m²) (P = .004), deep pancreas (pancreatic depth ≥51.2 mm) (P = .001), and low computed tomography attenuation index (≤-3.8 Hounsfield units) (P = .02) were significant risk factors for clinically relevant postoperative pancreatic fistula. The multivariate logistic regression analysis revealed that deep pancreas (odds ratio 2.370; 95% confidence interval 1.0019-5.590; P = .049) was an independent risk factor for clinically relevant postoperative pancreatic fistula. Among patients with a nondilated main pancreatic duct, deep pancreas (in comparison to patients without deep pancreas) was associated with male sex (72.7% vs 54.9%; P = .016), higher body mass index (22.5 kg/m² vs 19.6 kg/m²; P < .001), a history of diabetes mellitus (24.5% vs 8.5%; P = .006), a lower computed tomography attenuation index (-9.6 Hounsfield units vs -4.6 Hounsfield units; P = .007), a longer operative time (454 minutes vs 420 minutes; P = .007), and a higher volume of intraoperative blood loss (723 mL vs 500 mL; P < .001), respectively.

CONCLUSION

Deep pancreas may be an important parameter associated with significant risk factors for clinically relevant postoperative pancreatic fistula after pancreaticoduodenectomy in patients with a nondilated main pancreatic duct.

Predictive Factors for Postoperative Pancreatic Fistula-A Swedish Nationwide Register-Based Study

BACKGROUND

A serious complication after pancreatoduodenectomy (PD) is postoperative pancreatic fistula (POPF). The aim of this study was to analyse the incidence and predictive factors for POPF by using a large nationwide cohort.

METHODS

Data from the Swedish National Registry for Pancreatic and Periampullary Cancer for all patients undergoing a PD from 2010 until 30th June 2018 were collected. The material was analysed in two groups, no POPF and clinically relevant (grade B and C) POPF.

RESULTS

A total of 2503 patients underwent PD, of which 245 (10%) developed POPF. Patients with POPF had significantly more overall complications (Clavien Dindo ≥3a, 75% vs. 21%, p < 0.001) and longer hospital stay (median 23 [16-35] vs. 11 [8-15], p < 0.001) than patients without POPF. The risk of POPF was higher with increased BMI (OR 1.08, p < 0.001). Preoperative presence of diabetes (OR 0.52, p = 0.012) and preoperative biliary drainage (OR 0.34, p < 0.001) reduced the risk of POPF. Reconstruction with pancreaticojejunostomy caused a more than two folded increase in POPF compared with pancreaticogastrostomy (OR 2.41, p < 0.001). Weight gain ≥2 kg on postoperative day 1 was also a risk factor (OR 1.76, p < 0.001).

CONCLUSION

A high BMI, a pancreaticojejunostomy and postoperative weight gain were risk factors for developing POPF. Diabetes or preoperative biliary drainage was protective.

Influence of the Retrocolic Versus Antecolic Route for Alimentary Tract Reconstruction on Delayed Gastric Emptying After Pancreatoduodenectomy: A Multicenter, Noninferiority Randomized Controlled Trial

OBJECTIVE

This study aimed to determine whether retrocolic alimentary tract reconstruction is noninferior to antecolic reconstruction in terms of DGE incidence after pancreatoduodenectomy (PD) and investigated patients' postoperative nutritional status.

SUMMARY OF BACKGROUND DATA

The influence of the route of alimentary tract reconstruction on DGE after PD is controversial.

METHODS

Patients from 9 participating institutions scheduled for PD were randomly allocated to the retrocolic or antecolic reconstruction groups. The primary outcome was incidence of DGE, defined according to the 2007 version of the International Study Group for Pancreatic Surgery definition. Noninferiority would be indicated if the incidence of DGE in the retrocolic group did not exceed that in the antecolic group by a margin of 10%. Patients' postoperative nutrition data were compared as secondary outcomes.

RESULTS

Total, 109 and 103 patients were allocated to the retrocolic and antecolic reconstruction group, respectively (n = 212). Baseline characteristics were similar between both groups. DGE occurred in 17 (15.6%) and 13 (12.6%) patients in the retrocolic and antecolic group, respectively (risk difference; 2.97%, 95% confidence interval; -6.3% to 12.6%, which exceeded the specified margin of 10%). There were no differences in the incidence of other postoperative complications and in the duration of hospitalization. Postoperative nutritional indices were similar between both groups.

CONCLUSIONS

This trial could not demonstrate the noninferiority of retrocolic to antecolic alimentary tract reconstruction in terms of DGE incidence. The alimentary tract should not be reconstructed via the retrocolic route after PD, to prevent DGE.

Pre-, peri- and post-operative factors for the development of pancreatic fistula after pancreatic surgery

BACKGROUND

The most hazardous complication to pancreatic surgery is the development of a post-operative pancreatic fistula (POPF). Appropriate understanding of the underlying pathophysiology, risk factors and perioperative mechanisms may allow for better management and use of preventive measures.

METHODS

Systematic literature search using the English PubMed literature up to April 2019, with emphasis on the past 5 years.

RESULTS

Several risk scores have been developed but none are perfect in predicting POPF risk. A conceptual framework of factors that contribute to the pathophysiology of pancreatic fistulae is still developing but incomplete. Recognized factors include those related to the patient, the pathology and the perioperative care. Interventions such as use of drains, stents and various drugs to mediate risk is still debated. Emerging data suggest that both the microbiome and the inflammation in the post-operative phase may play important roles in risk for POPF. Available risk scores allow for stratification of risk and mitigation strategies tailored to reduce this. However, accurate estimation of risk remains a challenge and mechanisms are only partially understood.

CONCLUSIONS

The pathophysiology of POPF remains poorly understood. Current models only partially explain risks or associated mechanisms. Novel areas of investigation need to be explored for better prediction.

Fat-free mass index is superior to body mass index as a novel risk factor for prolonged air leak complicating video-assisted thoracoscopic surgery lobectomy for non-small-cell lung cancer

Background

To evaluate whether fat-free mass index (FFMI) could be predictive of prolonged air leak (PAL) complicating video-assisted thoracoscopic (VATS) lobectomy for non-small-cell lung cancer (NSCLC).

Methods

A retrospective study was conducted on the prospectively-maintained database in our institution between January 2015 and July 2017. The gender-specific median values of FFMI for males and females were applied as their respective cutoffs to stratify patients into low-FFMI group and high-FFMI group in initial univariable analyses. An effective multivariable logistic-regression analysis was then performed to demonstrate the predictive value of dichotomized FFMI.

Results

There were 1,091 surgical patients with NSCLC included (616 males and 475 females), with a PAL incidence of 14.6%. The median FFMI values among males and females were 17.3 and 14.6 kg/m², respectively. PAL cases in both male (16.9±1.5 vs. 17.4±1.5 kg/m²; P=0.002) and female (14.0±0.9 vs. 14.6±1.1 kg/m²; P<0.001) groups had a significantly lower mean FFMI than that of non-PAL cases. The incidence of PAL was significantly increased in male patients with FFMI <17.3 kg/m² (23.7% vs. 14.3%; P=0.003) and female patients with FFMI <14.6 kg/m² (12.7% vs. 5.0%; P=0.003). Lower dichotomized FFMI was also significantly associated with prolonged time to air leak cessation and length of stay (LOS). Finally, multivariable logistic-regression analysis indicated that lower dichotomized FFMI [odds ratio (OR) =1.98; 95% confidence interval (CI): 1.33-2.96; P=0.001] could independently predict the occurrence of PAL.

Conclusions

FFMI acts as an excellent categorical risk factor for PAL complicating VATS lobectomy and shows a much superior significance than body mass index (BMI) in terms of the prediction of PAL.

Elucidating early CT after pancreatico-duodenectomy: a primer for radiologists

Abstract

Pancreatico-duodenectomy (PD) represents the standard surgical treatment for resectable malignancies of the pancreatic head, distal common bile duct, periampullary region and duodenum, and is also performed to manage selected benign tumours and refractory chronic pancreatitis. Despite improved surgical techniques and acceptable mortality, PD remains a technically demanding, high-risk operation burdened with high morbidity (complication rates 40–50% of patients). Multidetector computed tomography (CT) represents the mainstay modality to rapidly investigate the postoperative abdomen, and to provide a consistent basis for an appropriate choice between conservative, interventional or surgical treatment. However, radiologists require familiarity with the surgically altered anatomy, awareness of expected imaging appearances and possible complications to correctly interpret early post-PD CT studies. This paper provides an overview of surgical indications and techniques, discusses risk factors and clinical manifestations of the usual postsurgical complications, and suggests appropriate techniques and indications for early postoperative CT imaging. Afterwards, the usual, normal early post-PD CT findings are presented, including transient fluid, pneumobilia, delayed gastric emptying, identification of pancreatic gland remnant and of surgical anastomoses. Finally, several imaging examples review the most common and some unusual complications such as pancreatic fistula, bile leaks, abscesses, intraluminal and extraluminal haemorrhage, and acute pancreatitis.

Teaching Points

• Pancreatico-duodenectomy (PD) is a technically demanding surgery burdened with high morbidity (40–50%).

• Multidetector CT is the mainstay technique to investigate suspected complications following PD.

• Interpreting post-PD CT requires knowledge of surgically altered anatomy and expected findings.

• CT showing collection at surgical site supports clinico-biological diagnosis of pancreatic fistula.

• Other complications include biliary leaks, haemorrhage, abscesses and venous thrombosis.