Recent Development of Augmented Reality in Surgery: A Review

INTRODUCTION

The development augmented reality devices allow physicians to incorporate data visualization into diagnostic and treatment procedures to improve work efficiency, safety, and cost and to enhance surgical training. However, the awareness of possibilities of augmented reality is generally low. This review evaluates whether augmented reality can presently improve the results of surgical procedures.

METHODS

We performed a review of available literature dating from 2010 to November 2016 by searching PubMed and Scopus using the terms "augmented reality" and "surgery." Results. The initial search yielded 808 studies. After removing duplicates and including only journal articles, a total of 417 studies were identified. By reading of abstracts, 91 relevant studies were chosen to be included. 11 references were gathered by cross-referencing. A total of 102 studies were included in this review.

CONCLUSIONS

The present literature suggest an increasing interest of surgeons regarding employing augmented reality into surgery leading to improved safety and efficacy of surgical procedures. Many studies showed that the performance of newly devised augmented reality systems is comparable to traditional techniques. However, several problems need to be addressed before augmented reality is implemented into the routine practice.

Non-alcoholic fatty liver disease: A sign of systemic disease

Non-alcoholic fatty liver disease (NAFLD) is the most common form of liver disease and leading cause of cirrhosis in the United States and developed countries. NAFLD is closely associated with obesity, insulin resistance and metabolic syndrome, significantly contributing to the exacerbation of the latter. Although NAFLD represents the hepatic component of metabolic syndrome, it can also be found in patients prior to their presentation with other manifestations of the syndrome. The pathogenesis of NAFLD is complex and closely intertwined with insulin resistance and obesity. Several mechanisms are undoubtedly involved in its pathogenesis and progression. In this review, we bring together the current understanding of the pathogenesis that makes NAFLD a systemic disease.

Role of tamsulosin, tadalafil, and silodosin as the medical expulsive therapy in lower ureteric stone: a randomized trial (a pilot study)

OBJECTIVE

To evaluate the role of 2 different α-1 blockers and 1 phosphodiesterase-5 inhibitor as medical expulsive therapy for distal ureteric calculi.

MATERIALS AND METHODS

Between January 2011 and December 2012, 285 patients presenting with distal ureteric stones of size 5-10 mm were on consent randomly assigned to 1 of 3 outpatient treatment arms: tamsulosin (group A), silodosin (group B), and tadalafil (group C). Therapy was given for a maximum of 4 weeks. Stone expulsion rate, time to stone expulsion, analgesic use, number of hospital visits for pain, follow-up, and endoscopic treatment and adverse effects of drugs were noted. All 3 groups were compared for normally distributed data by the analysis of variance, Bonferroni or Kruskal-Wallis test, and Mann-Whitney U test, as required. All the classified and categorical data were analyzed for all 3 groups by using the chi-square test.

RESULTS

There was a statistically significant expulsion rate of 83.3% in group B compared with 64.4% and 66.7% in groups A and C, respectively, with lower time of stone expulsion (P value = .006 and P value = .016, respectively). Statistically significant differences were noted in colicky episodes and analgesic requirement in group B than groups A and C. There was no serious adverse event.

CONCLUSION

Medical expulsive therapy for the distal ureteric stones using tamsulosin, silodosin, and tadalafil is safe, efficacious, and well tolerated. The result of this pilot study showed that silodosin increases ureteric stone expulsion quite significantly along with better control of pain with significantly lesser analgesic requirement.

Clinical outcomes of primary arterial embolization in severe hepatic trauma: A systematic review

PURPOSE

This purpose of this systematic review was to determine the safety and efficacy of arterial embolization as the primary treatment for grade III-V liver trauma, excluding the postoperative use of arterial embolization.

MATERIAL AND METHODS

A total of 24 studies published between January 2000 and June 2018 qualified for inclusion in this study. Four of them were prospective studies and 20 were retrospective. A total of 3855 patients (mean age, 33.5 years; range: 22-52.5 years) were treated non-operatively and 659 patients (659/3855; 17.09%) with hepatic hemorrhage underwent primary arterial embolization from 2000 to 2017. Indication for arterial embolization was a contrast blush visible on computed tomography in hemodynamically stable patient in all studies.

RESULTS

The arterial embolization success rate ranged from 80% to 97%. The most commonly reported complication was bile leak, with an incidence of 5.7%. Nineteen bilomas (2.8%) were reported in five studies with a range between 4% and 45%. Hepatic ischemia was reported in eight studies, with a mean incidence of 8.6%.

CONCLUSION

Primary arterial embolization has a high success rate in patients with hepatic trauma. Complications, including biloma and hepatic ischemia, have acceptable rates in the context of a minimally-invasive procedure that allows stabilization of life-threatening, complex liver injuries.

Animal models of human colorectal cancer: Current status, uses and limitations

AIM

To make orthotopic colon cancer murine models a more clearly understood subject. The orthotopic tumor models have been found to be more relevant in replicating the human disease process as compared to heterotopic models, many techniques for making orthotopic colorectal murine models have been reported.

METHODS

We evaluated the current literature for various reported orthotopic colon cancer models to understand their techniques, advantages and limitations. An extensive literature review was performed by searching the National Library of Medicine Database (PubMed) using MeSH terms animal model; colon cancer; orthotopic model; murine model. Twenty studies related to colon cancer orthotopic xenograft model were evaluated in detail and discussed here.

RESULTS

The detailed analysis of all relevant reports on orthotopic model showed tumor take rate between 42%-100%. While models using the enema technique and minimally invasive technique have reported development of tumor from mucosa with tumor take rate between 87%-100% with metastasis in 76%-90%.

CONCLUSION

Over the years, the increased understanding of the murine models of human colon cancer has resulted in the development of various models. Each reported model has some limitations. These latest models have opened up new doors for continuing cancer research for not only understanding the colon cancer pathogenesis but also aid in the development of newer chemotherapeutic drugs as they mimic the human disease closely.

Intrahepatic cholangiocarcinoma: Limitations for resectability, current surgical concepts and future perspectives

Intrahepatic cholangiocarcinoma (iCCA) is the second most common hepatic malignancy and its incidence has been shown to increase significantly during the past decades. Complete surgical resection is currently acknowledged as the only curative treatment option able to provide adequate long-term outcomes. We herein review technical, functional and oncologic limitations for resectability, discuss current surgical aspects as well as highlight the fields in which future research and practice should focus on in order to ameliorate long-term outcomes in patients with iCCA.

Tamsulosin versus tamsulosin plus tadalafil as medical expulsive therapy for lower ureteric stones: a randomized controlled trial

OBJECTIVES

To compare the efficacy of tamsulosin versus tamsulosin plus tadalafil as medical expulsive therapy for lower ureteric stones.

METHODS

Between January 2013 and December 2013, 244 patients presenting with distal ureteric stones (size 5-10 mm) were randomized equally to tamsulosin (group A) or tamsulosin plus tadalafil (group B). Therapy was given for a maximum of 4 weeks. Stone expulsion rate, time to stone expulsion, analgesic use, number of hospital visits for pain, follow up, endoscopic treatment and adverse effects of drugs were recorded. Statistical analyses were carried out using Student's t-test and the χ(2) -test.

RESULTS

There was a statistically significant higher expulsion rate in group B compared with group A (83.6% vs 65.5%; P-value = 0.031) and a shorter time to expulsion (14.9 ± 4.4 days vs 16.7 ± 4.8 days; P-value = 0.003). Statistically significant differences were noted in terms of the number of hospital visits and analgesic requirement in favor of group B. There was no serious adverse event. An improvement in erectile function was noted in patients of group B compared with those of group A.

CONCLUSIONS

Medical expulsive therapy for distal ureteric stones using tamsulosin plus tadalafil is safe, effective and well tolerated. Furthermore, tadalafil provides the additional advantage of improving erectile dysfunction when this condition coexists with a lower ureteric stone.

The demise of islet allotransplantation in the United States: A call for an urgent regulatory update

Islet allotransplantation in the United States (US) is facing an imminent demise. Despite nearly three decades of progress in the field, an archaic regulatory framework has stymied US clinical practice. Current regulations do not reflect the state-of-the-art in clinical or technical practices. In the US, islets are considered biologic drugs and "more than minimally manipulated" human cell and tissue products (HCT/Ps). In contrast, across the world, human islets are appropriately defined as "minimally manipulated tissue" and not regulated as a drug, which has led to islet allotransplantation (allo-ITx) becoming a standard-of-care procedure for selected patients with type 1 diabetes mellitus. This regulatory distinction impedes patient access to islets for transplantation in the US. As a result only 11 patients underwent allo-ITx in the US between 2016 and 2019, and all as investigational procedures in the settings of a clinical trials. Herein, we describe the current regulations pertaining to islet transplantation in the United States. We explore the progress which has been made in the field and demonstrate why the regulatory framework must be updated to both better reflect our current clinical practice and to deal with upcoming challenges. We propose specific updates to current regulations which are required for the renaissance of ethical, safe, effective, and affordable allo-ITx in the United States.

Prophylactic intra-abdominal drainage following colorectal anastomoses. A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Clinically evident Anastomotic Leakage (AL) remains one of the most feared complications after colorectal resections with primary anastomosis. The primary aim of this systematic review and meta-analysis was to determine whether Prophylactic Drainage (PD) after colorectal anastomoses confers any advantage in the prevention and management of AL.

METHODS

Systematic literature search was performed using MEDLINE, the Cochrane Central Register of Controlled Trials, and EMBASE databases for randomized studies comparing clinical outcomes of patients with Drained (D) or Undrained (UD) colorectal anastomoses performed for any cause.

RESULTS

Four randomized controlled trials comparing D and UD patients undergoing colorectal resections with primary anastomosis were included for quantitative synthesis. In total, 1120 patients were allocated to group D (n = 566) or group UD (n = 554). The clinical AL rate was 8.5% in the D group and 7.6% in the UD group, with no statistically significant difference (P = 0.57). Rates of radiological AL (D: 4.2% versus UD: 5.6%; P = 0.42), mortality (D: 3.6% versus UD: 4.4%; P = 0.63), overall morbidity (D: 16.6% versus UD: 18.6%, P = 0.38), wound infection (D: 5.4% versus UD: 5.3%, P = 0.95), pelvic sepsis (D: 9.7% versus UD: 10.5%, P = 0.75), postoperative bowel obstruction (D: 9.9% versus UD: 6.9%, P = 0.07), and reintervention for abdominal complication (D: 9.1% versus UD: 7.9%, P = 0.48) were equivalent between the two groups.

CONCLUSIONS

The present meta-analysis of randomized controlled trials investigating the value of PD following colorectal anastomoses does not support the routine use of prophylactic drains.

Comparative efficacy of tamsulosin versus tamsulosin with tadalafil in combination with prednisolone for the medical expulsive therapy of lower ureteric stones: a randomized trial

PURPOSE

To compare the safety and efficacy of tamsulosin and tamsulosin with the phosphodiesterase-5 inhibitor tadalafil in combination with prednisolone as medical expulsive therapies for lower ureteric stones.

MATERIALS AND METHODS

Between July 2011 and December 2012, 62 adult patients presenting with distal ureteric stones sized 5 to 10 mm were randomized equally to treatment with tamsulosin (group A) or tamsulosin with tadalafil (group B). Therapy was given for a maximum of 6 weeks. In addition, patients in groups A and B were given 5-mg prednisolone once daily (maximum 1 week). The stone expulsion rate, time to stone expulsion, analgesic use, number of hospital visits for pain, follow-up and endoscopic treatment, and adverse effects of the drugs were noted. Statistical analyses were done by using Student t-test and chi-square test.

RESULTS

There was a higher expulsion rate (83.9% in group B and 74.2% in group A) and a lower time to expulsion in both treatment groups than in historical controls used in earlier studies. However, these results were not statistically significant (p=0.349, p=0.074, respectively). Statistically significant differences were noted in hospitalization for colic and analgesic requirement, which were less in group B than in group A. There were no serious adverse events. Another important finding was improvement in erectile function in group B.

CONCLUSIONS

Medical expulsive therapy for distal ureteric stones using tamsulosin and tadalafil with prednisolone is safe and efficacious. Also, the prescription of tadalafil in cases of erectile dysfunction with the development of lower ureteric stones may provide additional advantages.

The Role of Normothermic Perfusion in Liver Transplantation (TRaNsIT Study): A Systematic Review of Preliminary Studies

INTRODUCTION

The success of liver transplantation has been limited by the unavailability of suitable donor livers. The current organ preservation technique, i.e., static cold storage (SCS), is not suitable for marginal organs. Alternatively, normothermic machine perfusion (NMP) promises to recreate the physiological environment and hence holds promise for the better organ preservation. The objective of this systematic review is to provide an overview of the safety, benefits, and insight into the other potential useful parameters of NMP in the liver preservation.

MATERIAL AND METHODS

We searched the current literature following registration in the International Prospective Register of Systematic Reviews (PROSPERO) with registration number CRD42018086034 for prospective trials comparing the role of NMP device to SCS in liver transplant by searching the PubMed, EMBASE, Cochrane, BIOSIS, Crossref, and Scopus databases and clinical trial registry.

RESULTS

The literature search identified five prospective clinical trials (four being early phase single institutional and single randomized multi-institutional) comparing 187 donor livers on NMP device to 273 donor livers on SCS. The primary outcome of interest was to assess the safety and graft survival at day 30 after transplant following NMP of the donor liver. Secondary outcomes included were early allograft dysfunction (EAD) in the first seven days; serum measures of liver functions as bilirubin, aspartate aminotransferase (AST), alanine amino transferase (ALT), alkaline phosphatase (ALP), and international normalized ratio (INR) on days 1-7; major complications as defined by a Clavien-Dindo score ≥ 3; and patient and graft survival and biliary complications at six months. The peaked median AST level between days 1 and 7 in the five trials was 417-1252 U/L (range 84-15009 U/L) while on NMP and 839-1474 U/L (range 153-8786 U/L) in SCS group. The median bilirubin level on day 7 ranged within 25-79 µmol/L (range 8-344 µmol/l) and 30-47.53 µmol/l (range 9-340 µmol/l) in NMP and SCS groups, respectively. A single case of PNF was reported in NMP group in the randomized trial while none of the other preliminary studies reported any in either group. There was intertrial variability in EAD which ranged within 15-56% in NMP group while being within 23-37% in SCS group. Biliary complications observed in NMP group ranged from 0 to 20%. Single device malfunction was reported in randomized controlled trial leading to renouncement of transplant while none of the other trials reported any machine failure, although two user related device errors inadvertent were reported.

CONCLUSION

This review outlines that NMP not only demonstrated safety and efficacy but also provided the favourable environment of organ preservation, repair, and viability assessment to donor liver prior to the transplantation with low rate of posttransplantation complication as PNF, EAD, and biliary complication; however further studies are needed to broaden our horizon.

Positive Immuno-Modulation Following Radiofrequency Assisted Liver Resection in Hepatocellular Carcinoma

INTRODUCTION

Hepatocellular carcinoma (HCC) often develops on a background of chronic inflammation and a complex immunosuppressive network with increased regulatory T cells, impaired CD8⁺ T cells and the secretion of immunosuppressive cytokines. Previous clinical studies have reported a superior disease-free survival (DFS) following a radiofrequency-based ablation or resection in HCC tumours compared to conventional liver resection techniques. The aim of this study was to investigate whether there is any correlation with the use of a radiofrequency-assisted liver resection and clinical outcome.

MATERIAL AND METHODS

Patients' peripheral blood was collected prior and 7 days following surgery from patients undergoing a liver resection for HCC. There were 5 liver resections performed using CUSA and 6 liver resections with the RF-based device, HabibTM 4X. The primary endpoint of the study was to assess the immunological parameters of circulating immune cell populations as well as serum cytokines. The Student's t-test, chi-square or Fisher's Exact test were applied for statistical comparisons, as appropriate.

RESULTS

Patients undergoing an RF-assisted liver resection with HabibTM 4X had a significant decrease in the inhibitory Treg cells (p = 0.002) and a significant increase in CD8⁺ T lymphocytes (p = 0.050) and CD4⁺CD45RO⁺/CD4⁺ memory T cells (p = 0.002) compared to those patients undergoing a liver resection with CUSA. It was also noted that the RF-assisted liver resection group had a significant decrease in circulating TGF-ß (p = 0.000), IL10 (p = 0.000) and a significant increase in IFN-gamma (p = 0. 027) and IL-17 compared to the CUSA group.

CONCLUSION

A liver resection with RF-based device HabibTM 4X was associated with positive immunomodulatory changes in circulating immune cells and circulating cytokines which could explain the significant improvement in DFS.

COVID-19 in hospitalized liver transplant recipients: An early systematic review and meta-analysis

Adverse clinical outcomes related to SARS-CoV-2 infection among liver transplant (LTx) recipients remain undefined. We performed a meta-analysis to determine the pooled prevalence of outcomes among hospitalized LTx recipients with COVID-19. A database search of literature published between December 1, 2019, and November 20, 2020, was performed per PRISMA guidelines. Twelve studies comprising 517 hospitalized LTx recipients with COVID-19 were analyzed. Common presenting symptoms were fever (71%), cough (62%), dyspnea (48%), and diarrhea (28%). Approximately 77% (95% CI, 61%-93%) of LTx recipients had a history of liver cirrhosis. The most prevalent comorbidities were hypertension (55%), diabetes (45%), and cardiac disease (21%). In-hospital mortality was 20% (95% CI, 13%-28%) and rose to 41% (95% CI, 19%-63%) (P < 0.00) with ICU admission. Additional subgroup analysis demonstrated a higher mortality risk in the elderly (>60-65 years) (OR 4.26; 95% CI, 2.14-8.49). There was no correlation in respect to sex or time since transplant. In summary, LTx recipients with COVID-19 had a high prevalence of dyspnea and gastrointestinal symptoms. In-hospital mortality was comparable to non-transplant populations with similar comorbidities but appeared to be less than what is reported elsewhere for cirrhotic patients (26%-40%). Importantly, the observed high case fatality in the elderly could be due to age-associated comorbidities.

Study to evaluate the immunomodulatory effects of radiofrequency ablation compared to surgical resection for liver cancer

Introduction: Hepatic cancer is a highly lethal tumour with increasing worldwide incidence. These tumours are characterized by the proliferation of malignant cells, generalised immunosuppression and chronic inflammation marked with an increase in inflammatory markers as a neutrophil-to-lymphocyte ratio (NLR), the platelet-to-lymphocyte ratio (PLR) and overexpression of CD4+CD39+ on T lymphocytes. The studies have outlined immunomodulatory changes in liver cancer patients as the plausible explanation for the better survival. The aim of this pilot study was understand the possible immunomodulatory effect of radiofrequency (RF) energy and liver resection (non-radiofrequency based devices; non-RF device) in relation to NLR, PLR and expression of CD4+CD39+ T lymphocytes and compare the magnitude of these changes. Material and Methods: In the present study, 17 patients with hepatic cancer were prospectively divided into treatment groups radiofrequency ablation (RFA group) and Liver resection using non-RF devices (LR group). A blood sample was collected from each patient, one month before and after the procedure and compared with the blood samples of age-matched healthy volunteers for group wise comparison. The Mann-Whitney U test, Mc Nemar test and Wilcoxon rank test were used for statistical comparisons as appropriate. Results: A decrease in NLR was reported after RFA from 4.7±3.3 to 3.8±1.8 (P=0.283), in contrary to an increase from 3.5±2.8 to 4.5±3.2 (P=0.183) in LR group. Likewise, a decrease was discerned in PLR following RFA from 140.5±79.5 to 137±69.2 respectively (P=0.386) and increase in the LR group from 116±42.2 to 120.8±29 respectively (P=0.391). A significant decrease in CD4+CD39+ lymphocytes from 55.8±13.8 to 24.6±21.1 (P=0.03) was observed in RFA group whilst a significant increase was reported in LR group from 47.6±8.8 to 55.7±33.2 (P=0.38). Conclusion: Studies have shown that decrease in the NLR, PLR and expression of CD4+CD39+ on T lymphocytes as the marker of better survival in hepatic cancer patients and our findings have confirmed that these changes can be induced following application of RF energy. Moreover, this could be the explanation of better survival observed in different studies using RFA or other RF-based devices in comparison to non-RF based liver resection techniques. However, further larger studies are needed to confirm these findings.

Impact of cavitron ultrasonic surgical aspirator (CUSA) and bipolar radiofrequency device (Habib-4X) based hepatectomy for hepatocellular carcinoma on tumour recurrence and disease-free survival

BACKGROUND

The aim of this study was to evaluate the oncological outcomes of hepatocellular carcinoma patients undergoing liver resection using cavitron ultrasonic surgical aspirator (CUSA) or radiofrequency (RF) based device Habib-4X.
.

STUDY DESIGN

We prospectively analyzed the data of 280 patients who underwent liver resection for hepatocellular carcinoma at our institution from 2010-2012 with follow up till August 2016. The CUSA was used in the 163 patients whilst Habib-4X in 117 patients. The end points of analysis were oncological outcomes as disease recurrence, disease-free survival (DFS) and overall survival (OS) were estimated by the Kaplan-Meier method, which has been compared with all other existing literature on the survival study.

RESULTS

Compared with CUSA the reported incidence of recurrence was significantly lower, in Habib-4X group; p < 0.01. The median DFS was significantly better in Habib-4X group than CUSA group (50.80 vs 45.87 months, p = 0.03). The median OS was better in Habib-4X group than CUSA group (60.57 vs 57.17 months, p = 0.12) though the lesser difference in OS between the groups might be explained by the use of palliative therapies as TACE, percutaneous RFA, etc. in case of recurrence.

CONCLUSIONS

RF based device Habib-4X, is safe and effective device for resection of hepatocellular carcinoma, in comparison to CUSA with better oncological outcomes, i.e., significantly lesser tumour recurrence and better DFS. This could be explained on the basis of systemic and local immunomodulatory effect involving induction of kupffer cells and effector CD-8 T cells that help in minimizing postoperative complications and bring more advantageous oncological outcomes.

Radiofrequency combined with immunomodulation for hepatocellular carcinoma: State of the art and innovations

Hepatocellular carcinoma (HCC) is the most common primary liver tumor and has been considered a very immunogenic tumor. The treatment with radiofrequency ablation (RFA) has been established as the standard ablative therapy for early HCC, and is currently recognized as the main ablative tool for HCC tumors < 5 cm in size; however, progression and local recurrence remain the main disadvantages of this approach. To solve this clinical problem, recent efforts were concentrated on multimodal treatment, combining different strategies, including the combination of RFA and immunotherapy. This article reviewed the combination treatment of RFA with immunotherapy and found that this treatment strategy leads to an increased response of anti-tumor T cells, significantly reduces the risk of recurrence and improves survival rates compared to RFA alone. This review highlighted scientific evidence that supports the current recommendations for pre-clinical studies, and discuss the need for further research on this topic.

Systematic Review and Meta-Analysis on the Impact of Thrombolytic Therapy in Liver Transplantation Following Donation after Circulatory Death

AIM

The livers from DCD (donation after cardiac death) donations are often envisaged as a possible option to bridge the gap between the availability and increasing demand of organs for liver transplantation. However, DCD livers possess a heightened risk for complications and represent a formidable management challenge. The aim of this study was to evaluate the effects of thrombolytic flush in DCD liver transplantation.

METHODS

An extensive search of the literature database was made on MEDLINE, EMBASE, Cochrane, Crossref, Scopus databases, and clinical trial registry on 20 September 2018 to assess the role of thrombolytic tissue plasminogen activator (tPA) flush in DCD liver transplantation.

RESULTS

A total of four studies with 249 patients in the tPA group and 178 patients in the non-tPA group were included. The pooled data revealed a significant decrease in ischemic-type biliary lesions (ITBLs) (P = 0.04), re-transplantation rate (P = 0.0001), and no increased requirement of blood transfusion (P = 0.16) with a better one year graft survival (P = 0.02).

CONCLUSIONS

To recapitulate, tPA in DCD liver transplantation decreased the incidence of ITBLs, re-transplantation and markedly improved 1-year graft survival, without any increased risk for blood transfusion, hence it has potential to expand the boundaries of DCD liver transplantation.

Belatacept in renal transplantation in comparison to tacrolimus and molecular understanding of resistance pattern: Meta-analysis and systematic review

BACKGROUND

The T-cell costimulation blocking agent belatacept has been identified as a possible substitute for calcineurin inhibitors, however, no consensus has been established against its use over the standard care agent Tacrolimus.

AIM

To evaluate the effectiveness of belatacept based maintenance immuno-suppressive regimens in comparison to tacrolimus in renal transplantion.

METHODS

We did extensive search of all the available literature comparing the role of belatacept to tacrolimus in renal transplant recipients by searching the PubMed, Embase, Cochrane, Crossref, Scopus, clinical trials registry on October 5, 2020.

RESULTS

The literature search identified four randomized controlled trials (n = 173 participants) comparing belatacept with tacrolimus. There was no significant difference in estimated renal function at 12 mo [mean difference 4.12 mL/min/1.73 m2, confidence interval (CI): -2.18 to 10.42, P = 0.20]. Further, belatacept group was associated with significant increase in biopsy proven acute rejection [relative risk (RR) = 3.27, CI: 0.88 to 12.11, P = 0.08] and worse 12 mo allograft survival (RR = 4.51, CI: 1.23 to 16.58, P = 0.02). However, incidence of new onset diabetes mellitus was lower with belatacept at 12 mo (RR = 0.26, CI: 0.07 to 0.99, P = 0.05).

CONCLUSION

The evidence reviewed in this meta-analysis suggested that belatacept-based maintenance immunosuppression regimens were associated with an increased risk allograft loss in renal transplant recipients with equivalent renal functioning against standard tacrolimus; however, observed significantly reduced new onset diabetes mellitus after transplantation incidence and lower serum low density lipid profile levels in belatacept group. In addition, the adaptation of belatacept in renal transplantation has been forestalled by increased rates of rejection and resistance owing to development of various effector memory T cells through, parallel differentiation and immunological plasticity.

coMpliAnce with evideNce-based cliniCal guidelines in the managemenT of acute biliaRy pancreAtitis): The MANCTRA-1 international audit

BACKGROUND/OBJECTIVES

Reports about the implementation of recommendations from acute pancreatitis guidelines are scant. This study aimed to evaluate, on a patient-data basis, the contemporary practice patterns of management of biliary acute pancreatitis and to compare these practices with the recommendations by the most updated guidelines.

METHODS

All consecutive patients admitted to any of the 150 participating general surgery (GS), hepatopancreatobiliary surgery (HPB), internal medicine (IM) and gastroenterology (GA) departments with a diagnosis of biliary acute pancreatitis between 01/01/2019 and 31/12/2020 were included in the study. Categorical data were reported as percentages representing the proportion of all study patients or different and well-defined cohorts for each variable. Continuous data were expressed as mean and standard deviation. Differences between the compliance obtained in the four different subgroups were compared using the Mann-Whitney U, Student's t, ANOVA or Kruskal-Wallis tests for continuous data, and the Chi-square test or the Fisher's exact test for categorical data.

RESULTS

Complete data were available for 5275 patients. The most commonly discordant gaps between daily clinical practice and recommendations included the optimal timing for the index CT scan (6.1%, χ2 6.71, P = 0.081), use of prophylactic antibiotics (44.2%, χ2 221.05, P < 0.00001), early enteral feeding (33.2%, χ2 11.51, P = 0.009), and the implementation of early cholecystectomy strategies (29%, χ2 354.64, P < 0.00001), with wide variability based on the admitting speciality.

CONCLUSIONS

The results of this study showed an overall poor compliance with evidence-based guidelines in the management of ABP, with wide variability based on the admitting speciality. Study protocol registered in ClinicalTrials.Gov (ID Number NCT04747990).

Interventional radiofrequency ablation: A promising therapeutic modality in the management of malignant biliary and pancreatic duct obstruction

Background: Malignant biliary and/or pancreatic obstruction has often encountered in the advanced stages of periampullary and cholangicarcinomas. HabibTM Radiofrequency (RF) ablation has been successfully used in the management of various cancers of liver and pancreas. Percutaneous HPB probe (EMcision Ltd, London, UK) is a new addition to this class of tools. It is an endoluminal Radiofrequency (RF) catheter which works on the principle of ablation and induces coagulative necrosis to recanalize the obstructed duct. The aim of this study is to address the technical details of canalization, feasibilities and outcomes of percutaneous endo-luminal Radiofrequency (RF) catheter in patients with unresectable malignancy with obstructed bile and pancreatic duct (PD). Material and Method: A total of 134 patients with inoperable malignant obstruction of biliary and PD underwent RF based percutaneous endoluminal RF ablation in a tertiary referral centre between December 15th, 2010 to August 7th, 2015. This device was used in a sequential manner with an intent to recanalize the obstructed. Following the initial catheter drainage of the duct, subsequent percutaneous endobiliary RF ablation, the metallic stent was placed to recanalize the obstructed bile and PD secondary to unresectable malignancy under real-time fluoroscopic guidance. Results: The percutaneous RF based ablation of obstructed bile duct and PD with metallic stent placement was successfully achieved in 130 (97.01%) cases. The three failures were noted in cases of biliary obstruction whilst, one with PD obstruction. The patency restored in 124 and patients, where the procedure was successfully completed and revealed clinical improvement reported. Conclusion: The percutaneous endoluminal RF based ablation of obstructed duct with metallic stent placement appeared to be a safe, effective procedure and may improve survival in patients with advanced stage cancer presenting with biliary and PD obstruction. Considering the above mentioned evidence, this modality may stand ahead of stenting alone. This could be considered as viable modality in management of such patients where very limited treatment options are available.

Normothermic ex-vivo liver perfusion: where do we stand and where to reach?

Nowadays liver transplantation is considered as the treatment of choice, however, the scarcity of suitable donor organs limits the delivery of care to the end-stage liver disease patients leading to the death while on the waiting list. The advent of ex-situ normothermic machine perfusion (NMP) has emerged as an alternative to the standard organ preservation technique, static cold storage (SCS). The newer technique promises to not only restore the normal metabolic activity but also attempt to recondition the marginal livers back to the pristine state, which are otherwise more susceptible to ischemic injury and foster the poor post-transplant outcomes. Areas covered: An extensive search of all the published literature describing the role of NMP based device in liver transplantation as an alternative to SCS was made on MEDLINE, EMBASE, Cochrane, BIOSIS, Crossref, Scopus databases and clinical trial registry on 10 May 2018. Expert commentary: The main tenet of NMP is the establishment of the physiological milieu, which permits aerobic metabolism to continue through out the period of preservation and limits the effects of ischemia-reperfusion (I/R) injury. In addition, by assessing the various metabolic and synthetic parameters the viability and suitability of donor livers for transplantation can be determined. This important technological advancement has scored satisfactorily on the safety and efficacy parameters in preliminary clinical studies. The present review suggests that NMP can offer the opportunity to assess and safely utilize the marginal donor livers if deemed appropriate for the transplantation. However, ongoing trials will determine its full potential and further adoption.

Rare adrenal gland emergencies: a case series of giant myelolipoma presenting with massive hemorrhage and abscess

INTRODUCTION

Adrenal Myelolipoma is a rare benign neoplasm, which contains mature adipose tissue and variable amounts of haematopoietic elements. Most lesions are small and asymptomatic, discovered incidentally during autopsy or imaging studies performed for other reasons.

CASE PRESENTATION

Here we reported a series of two cases of giant myelolipomas of the adrenal gland; first one the largest tumor reported so far presented with massive hemorrhage and the second case introduced with its rare unreported presentation of adrenal myelolipomas i.e. a large abscess.

DISCUSSION

Adrenal myelolipoma is a rare and asymptomatic tumor usually discovered incidentally in less than 1% of population on autopsy or imaging performed for other reasons. There is an increasing incidence of large adrenal myelolipoma (> 10 cm) presenting with life threatening and recurrent retroperitoneal hemorrhage along with other complications as abscess. To avoid such a life-threatening situation, authors recommend close monitoring and consideration of urgent surgical intervention for tumors larger than 4 cm at presentation or increase in size or change in appearance during follow-up.

The Impact of COVID-19 on Kidney Transplant Recipients in Pre-Vaccination and Delta Strain Era: A Systematic Review and Meta-Analysis

Herein, we performed a meta-analysis of published clinical outcomes of corona virus disease 2019 (COVID-19) in hospitalized kidney transplant recipients. A systematic database search was conducted between December 1, 2019 and April 20, 2020. We analyzed 48 studies comprising 3137 kidney transplant recipients with COVID-19. Fever (77%), cough (65%), dyspnea (48%), and gastrointestinal symptoms (28%) were predominant on hospital admission. The most common comorbidities were hypertension (83%), diabetes mellitus (34%), and cardiac disease (23%). The pooled prevalence of acute respiratory distress syndrome and acute kidney injury were 58% and 48%, respectively. Invasive ventilation and dialysis were required in 24% and 22% patients, respectively. In-hospital mortality rate was as high as 21%, and increased to over 50% for patients in intensive care unit (ICU) or requiring invasive ventilation. Risk of mortality in patients with acute respiratory distress syndrome (ARDS), on mechanical ventilation, and ICU admission was increased: OR = 19.59, OR = 3.80, and OR = 13.39, respectively. Mortality risk in the elderly was OR = 3.90; however, no such association was observed in terms of time since transplantation and gender. Fever, cough, dyspnea, and gastrointestinal symptoms were common on admission for COVID-19 in kidney transplant patients. Mortality was as high as 20% and increased to over 50% in patients in ICU and required invasive ventilation.

Percutaneous Image-Guided Pancreatic Duct Drainage: Technique, Results and Expected Benefits

PURPOSE

The aim of this study is to provide a technical detail and feasibility of percutaneous image-guided pancreatic duct (PD) drainage and to discuss its subtleties in a series of patients with obstructed PD.

MATERIALS AND METHODS

Thirty patients presenting with PD obstruction from pancreatic head tumour or pancreatitis were subjected to percutaneous image-guided PD drainage under a guidance of ultrasound or computed tomography. Following the successful puncture of PD, a locking loop drainage catheter was placed using conventional guidewire techniques under real-time fluoroscopy guidance.

RESULTS

The percutaneous drainage of obstructed PD was completed in 29 (96.7%) patients as an independent therapeutic intent or as a bridge to further percutaneous procedures. Clinical improvement following drainage was documented by the gradual reduction in clinical symptoms, including pain, nausea and fever and improved blood test results, showing the significant decrease of amylase concentration. The amount of pancreatic fluid drained post procedure was between 300 and 900 mL/day. No major procedure-related complications were observed. Subsequently, 14 of 29 patients underwent further procedures, including endoluminal placement of metal stent with or without radiofrequency ablation, balloon assisted percutaneous descending litholapaxy (BAPDL), endoluminal biopsy and balloon dilatation using the same drainage tract.

CONCLUSION

The percutaneous PD drainage appears to be a safe and effective procedure. It should be considered in patients with obstructed PD secondary to malignancy, pancreatitis etc., where endoscopic retrograde cannulation has been failed or impracticable. The procedure can also be contemplated either as an independent treatment option or as an initial step for the subsequent therapeutic endoluminal procedures.