Systematic Review and Meta-Analysis of the Variants of the Obturatory Artery.

BACKGROUND: Knowledge of vascular anatomy and its possible variations is essential for performing embolization or revascularization procedures and complex surgery in the pelvis. The obturator artery (OA) is a branch of the anterior division of the internal iliac artery (IIA), and it has the highest frequency of variation among branches of the internal iliac artery. Possible anomalies of the origin of the obturator artery (OA) should be known when performing pelvic and groin surgery, where its control or ligation may be required. The purpose of this systematic review and meta-analysis, based on Sanudo's classification, is to analyze the origin of the obturator artery (OA) and its variants. METHODS: Thirteen articles published between 1952 and 2020 were included. RESULTS: The obturator artery (OA) was present in almost all cases (99.8%): the pooled prevalence estimate for the origin from the IIA axis was 77.7% (95% CI 71.8-83.1%) vs. 22.3% (95% CI 16.9-28.2%) for the origin from EIA axis. In most cases, the obturator artery (OA) originated from the anterior division trunk of the internal iliac artery (IIA) (61.6%). CONCLUSIONS: Performing preoperative radiological examination to determine the pelvic vascular pattern and having the awareness to evaluate possible changes in the obturator artery can reduce the risk of iatrogenic injury and complications.

Discontinuity of marginal artery at splenic flexure and rectosigmoid junction: A systematic review and meta-analysis.

AIM: The aim of this study was to provide comprehensive evidence-based assessment of the discontinuity of the marginal artery at the splenic flexure (SF) and the rectosigmoid junction (RSJ). METHOD: A systematic review was conducted of literature published to 26 December 2022 in the electronic databases PubMed, SCOPUS and Web of Science to identify studies eligible for inclusion. Data were extracted and pooled into a meta-analysis using the Metafor package in R. The primary outcomes were the pooled PPEs of the marginal artery at the SF and the RSJ. The secondary outcome was the size of vascular anastomoses. RESULTS: A total of 21 studies (n = 2,864 patients) were included. The marginal artery was present at the splenic flexure in 82% (95% CI: 62-95) of patients. Approximately 81% (95% CI: 63-94%) of patients had a large macroscopic anastomosis, while the remainder (19%) had small bridging ramifications forming the vessel. The marginal artery was present at the RSJ in 82% (95% CI: 70-91%) of patients. CONCLUSION: The marginal artery may be absent at the SF and the RSJ in up to 18% of individuals, which may confer a higher risk of ischaemic colitis. As a result of high interstudy heterogeneity noted in our analysis, further well-powered studies to clarify the prevalence of the marginal artery at the SF and the RSJ, as well as its relationship with other complementary colonic collaterals (intermediate and central mesenteric), are warranted.

Prevalence of the Retro-Renal Colon: A Systematic Review and Meta-Analysis with Implications for Percutaneous Nephrolithotomy.

Background: This systematic review and meta-analysis aims to determine the prevalence of the retrorenal colon (RRC) and its implications in percutaneous nephrolithotomy with the overall objective of promoting the prevention of associated iatrogenic complications. Methods: A systematic search of literature was conducted on the electronic databases PubMed, ScienceDirect, and Hinari to identify studies eligible for inclusion. Search results were screened by title and abstract, and those potentially relevant were evaluated by full text. Studies were deemed eligible for inclusion if they reported clear extractable data regarding the prevalence of the retro-renal colon. A meta-analysis was completed using MetaX1 to calculate the pooled prevalence of the retro-renal colon. Sub-group analysis was performed based on geographical regions from which the studies originated, imaging modality, and patient position. Results: 174 records were screened and a total of 10 records included in the analysis with retrospective cohort studies being the most common study design. A male predominance was seen in most sample sizes that had reported data on gender demographics ranging from 41.5-62%. The most common imaging modality utilized was computerized tomography (CT) scan followed by ultrasound. The range of the unweighted prevalence of retro-renal colon across all studies that had absolute numbers reported was from 3.5-25%. One of the studies reported a colonic perforation rate of 0.3% in patients without CT images. Conclusion: The retro-renal colon is a relatively common finding with observed preponderance to females and left lateralization. The presence of RRC increases the likelihood of colon perforations while gaining percutaneous access to the kidney. Pre-procedural imaging can help detect its presence and choose an appropriate route of entry. USG and CT have both been found useful as a modality to pick up RRC.

The Unusual High Origin Radial Artery in a Black Kenyan Population: A Cadaveric Study.

Background: The anatomy of the radial artery draws great interests among anatomists for its frequent involvement in variations. Equally, these variations have gained significant attention from clinicians because of the preference to use the radial artery for catheterization. The commonest of radial artery variations involve its site of origin. In published literature, data on this variations exist, but the prevalence of such variations in a Kenyan population has hitherto been unknown. Methods: Sixty-two upper limbs from 50 formalin-fixed cadavers were studied during dissection in the Department of Human Anatomy, University of Nairobi. Results: Fifty-four (87.1%) radial arteries arose within the cubital fossa, while eight (12.9%) had a high origin. Out of the eight high arteries, two (3.2%) branched off from the axillary artery, another two (3.2%) were branches of the proximal third of the brachial artery and four (6.5%) arose from the middle third of the brachial artery. The high origin radial arteries were more common on the right upper limbs (5 out of the 8 cases). Both axillary and brachial origins were seen bilaterally. Conclusion: The present study details important variations in the anatomy of the radial artery in a Kenyan population. With the radial artery being utilized during clinical, surgical and radiological interventions so frequently, an increased understanding and anticipation of such topographic variances is paramount.

Cell-Free DNA, Neutrophil extracellular traps (NETs), and Endothelial Injury in Coronavirus Disease 2019- (COVID-19-) Associated Acute Kidney Injury.

Introduction: Neutrophil extracellular traps (NETs) release (i.e., NETosis) has been recently implicated in the pathomechanism underlying severe end-organ damage in Coronavirus Disease 2019 (COVID-19) and could present a novel therapeutic target. We aimed to determine whether circulating levels of cell-free DNA (cfDNA), a surrogate for NETosis, may be associated with the development of acute kidney injury (AKI), a major contributor to poor outcomes and mortality in COVID-19. Methods: Blood samples were collected prospectively from adult patients infected with SARS-CoV-2 presenting to the emergency department (ED). Circulating levels of cfDNA were quantified from patients' serum. Further assessment of correlations between cfDNA levels and markers of AKI (i.e., serum creatinine (SCr), cystatin C, neutrophil gelatinase-associated lipocalin (NGAL)), biomarkers of thrombotic microangiopathy and of inflammation in patients' serum was performed. Results: Fifty-one COVID-19 patients were enrolled. cfDNA levels were found to be significantly higher in those who developed severe AKI (p < 0.001) and those needing renal replacement therapy (p = 0.020). cfDNA positively correlated with ED SCr, NGAL, cystatin C, neutrophil count, neutrophil-to-lymphocyte ratio, C3a, C5a, Scb5-9, IL-6, IL-8, IL-10, TNF-α, LDH, CRP, ferritin, and fibrinogen and negatively correlated with ADAMTS13/von-Willebrand factor ratio and lymphocyte count. In a multivariate logistic regression, a one-unit increase in cfDNA value was associated with 4.6% increased odds of severe AKI (OR = 1.046; p = 0.040). Finally, cfDNA significantly correlated with established NETs components, myeloperoxidase, and neutrophil elastase. Conclusion: Intravascular NETosis could be an important contributing factor in the development of microthrombosis and COVID-19-associated AKI. Further research is urgently needed to understand the role of NETosis in COVID-19 and evaluate therapeutic avenues for targeting this process.

Tocilizumab in addition to standard of care in the management of COVID-19: a meta-analysis of RCTs.

OBJECTIVE: We performed a systematic review and meta-analysis for exploring clinical benefits and safety of tocilizumab in addition to standard of care (SOC) in treating patients with coronavirus disease 2019 (COVID-19). METHODS: An electronic search was carried out in PubMed, EMBASE, Cochrane Library, and Science Direct, as well as in medRxiv preprint server, to identify eligible studies. Only randomized Controlled Trials (RCTs) that compared mortality events and/or adverse events between a tocilizumab + SOC group and a SOC-only control group were included. The primary outcome was 28-day mortality. Secondary outcomes include progression to severe disease, defined as need for mechanical ventilation (MV) or intensive care unit (ICU) admission, and adverse events (AE). RESULTS: A total of nine studies (6,490 participants) could be included in this meta-analysis, with 3,358 participants in the tocilizumab + SOC group and 3,132 participants in the SOC-only group. The overall mortality rate was lower in the tocilizumab group compared to the SOC-only group, though the difference was not statistically significant (odds ratio [OR], 0.87; 95% CI, 0.73-1.04; I2, 15%). This finding was unaffected by subgroup analyses based on initial use of steroids or mechanical ventilation at baseline. Patients receiving tocilizumab were 26% less likely to progress to MV, and this difference was statistically significant (OR, 0.74; 95% CI, 0.64-0.86; I2, 0%). Among patients who were not in ICU at randomization, the tocilizumab group had 34 % lower rate of ICU admission compared to the SOC-only group (OR, 0.66; 95% CI, 0.40-2.14; I2, 29%). The occurrence of serious infections was lower in the tocilizumab group (OR, 0.57; 95% CI, 0.36-0.89; I2, 21%). CONCLUSION: Tocilizumab is generally well-tolerated in COVID-19. Although this drug does not appear to have a significant benefits on survival, it may have a role in preventing progression to intensive care and MV.

Early prediction of COVID-19-associated acute kidney injury: Are serum NGAL and serum Cystatin C levels better than serum creatinine?

BACKGROUND: Coronavirus disease-2019 (COVID-19) is associated with a high risk of acute kidney injury (AKI), often requiring renal replacement therapy (RRT). Serum Cystatin C (sCysC) and serum Neutrophil Gelatinase-Associated Lipocalin (sNGAL) are emerging biomarkers for kidney injury, and were suggested to be superior to serum creatinine (sCr) in several clinical settings. Moreover, elevated sCysC is associated with disease severity and mortality in COVID-19. We aimed to assess the utility of sCysC and sNGAL for predicting COVID-19-associated AKI, need for RRT, and need for intensive care unit (ICU) admission, when measured at presentation to the emergency department (ED). METHODS: Patients presenting to the ED with laboratory-confirmed COVID-19 were included. The primary outcome was development of COVID-19-associated AKI, while the secondary outcomes were need for RRT and ICU admission. RESULTS: Among 52 COVID-19 patients, 22 (42.3%) developed AKI with 8/22 (36.4%) requiring RRT. Both sCr and sCysC demonstrated excellent performance for predicting AKI (AUC, 0.86 and 0.87, respectively) and need for RRT (AUC, 0.94 and 0.95, respectively). sNGAL displayed acceptable performance for predicting AKI (AUC, 0.81) and need for RRT (AUC, 0.87). CONCLUSIONS: SCr and sCysC measured at ED presentation are both highly accurate predictors of AKI and need for RRT, whereas sNGAL demonstrated adequate diagnostic performance. While sCyC was previously shown to be superior to sCr as a diagnostic biomarker of kidney injury in certain etiologies, our findings demonstrate that sCr is comparable to sCyC in the context of predicting COVID-19-associated AKI. Given the high sensitivity of these biomarkers for predicting the need for RRT, and as sCysC is associated with mortality in COVID-19 patients, we recommend their measurement for enabling risk stratification and early intervention.

Cytokeratin 18 cell death assays as biomarkers for quantification of apoptosis and necrosis in COVID-19: a prospective, observational study.

BACKGROUND: The mechanism by which SARS-CoV-2 triggers cell damage and necrosis are yet to be fully elucidated. We sought to quantify epithelial cell death in patients with COVID-19, with an estimation of relative contributions of apoptosis and necrosis. METHODS: Blood samples were collected prospectively from adult patients presenting to the emergency department. Circulating levels of caspase-cleaved (apoptosis) and total cytokeratin 18 (CK-18) (total cell death) were determined using M30 and M65 enzyme assays, respectively. Intact CK-18 (necrosis) was estimated by subtracting M30 levels from M65. RESULTS: A total of 52 COVID-19 patients and 27 matched sick controls (with respiratory symptoms not due to COVID-19) were enrolled. Compared with sick controls, COVID-19 patients had higher levels of M65 (p = 0.046, total cell death) and M30 (p = 0.0079, apoptosis). Hospitalised COVID-19 patients had higher levels of M65 (p= 0.014) and intact CK-18 (p= 0.004, necrosis) than discharged patients. Intensive care unit (ICU)-admitted COVID-19 patients had higher levels of M65 (p= 0.004), M30 (p= 0.004) and intact CK-18 (p= 0.033) than hospitalised non-ICU admitted patients. In multivariable logistic regression, elevated levels of M65, M30 and intact CK-18 were associated with increased odds of ICU admission (OR=22.05, p=0.014, OR=19.71, p=0.012 and OR=14.12, p=0.016, respectively). CONCLUSION: Necrosis appears to be the main driver of hospitalisation, whereas apoptosis and necrosis appear to drive ICU admission. Elevated levels CK-18 levels are independent predictors of severe disease, and could be useful for risk stratification of COVID-19 patients and in assessment of therapeutic efficacy in early-phase COVID-19 clinical trials.

Prevalence of femoral vein duplication: systematic review and metaanalysis.

Background: Duplication of the femoral vein is an important anatomical variation of the venous anatomy which has been shown to have an impact on the diagnosis of deep venous thrombosis by compression ultrasonography. The presence of duplication may result in false negative findings while evaluating for deep venous thrombosis, with serious consequences such as pulmonary embolism and death. This metaanalysis aims to determine the pooled prevalence of duplicated femoral veins. Methods: A systematic search was conducted through the major databases PubMed, Hinari, Embase and Medline to identify studies eligible for inclusion. Appropriate data were extracted and pooled into a random-effects metaanalysis using MetaXL software. The primary and secondary outcomes of the study included the pooled prevalence of duplicated femoral veins and the prevalence of bilaterally duplicated femoral veins, respectively. Results: A total of 11 studies (n = 3,682 limbs) were included. The overall pooled prevalence of duplicated femoral veins was 19.7% (95% CI 11-30). There was a significant difference in prevalence between cadaveric studies (2%, 95% CI 1-4) and imaging studies (25%, 95% CI 17-34). Conclusion: Duplication of the femoral vein is a common variation in the lower limbs. Routine watch-out should be practiced especially when performing lower limb Doppler studies in cases of deep venous thrombosis in order to avoid misdiagnosis and improve diagnostic accuracy.

Combined Cytokine Scores Assessed at Emergency Department Presentation Predicts COVID-19 Critical Illness.

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A systematic review and meta-analysis of variants of the branches of the superior mesenteric artery: the Achilles heel of right hemicolectomy with complete mesocolic excision?

AIM: Dissection with subsequent ligation and resection of arteries at their origin (central vascular ligation) is essential for adequate oncological resection during right hemicolectomy with complete mesocolic excision. This technique is technically demanding due to the highly variable arterial pattern of the right colon. Therefore, this study aims to provide a comprehensive evidence-based assessment of the arterial vascular anatomy of the right colon. METHODS: A thorough systematic literature search through September 2020 was conducted on the electronic databases PubMed, Scopus and Web of Science to identify studies eligible for inclusion. Data were extracted and pooled into a meta-analysis using MetaXl software. RESULTS: A total of 41 studies (n = 4691 patients) were included. The ileocolic artery (ICA), right colic artery (RCA) and middle colic artery (MCA) were present in 99.7% (95% CI 99.4%-99.8%), 72.6% (95% CI 61.3%-82.5%) and 96.9% (95% CI 94.2%-98.8%) respectively of patients. Supernumerary RCA and MCA were observed in 3.2% and 11.4% respectively of all cases. The RCA shared a common trunk with the ICA and MCA in 13.2% and 17.7% respectively of patients. A retro-superior mesenteric vein course of the ICA and RCA was observed in 55.1% and 11.4% respectively of all cases. CONCLUSION: The vascular anatomy of the right colon displays several notable variations, namely the absence of some branches (RCA absent in 27.4% of cases), supernumerary branches, common trunks, and retro-superior mesenteric vein courses. These variations should be taken into consideration during right hemicolectomy with complete mesocolic excision to ensure adequate oncological resection while minimizing intra-operative complications.

A systematic review and meta-analysis of iliocapsularis muscle: an important landmark in orthopedic surgery.

PURPOSE: Iliocapsularis (IC) is a small muscle overlying the capsule of the hip joint. Although recent attention is being given to this muscle by orthopedic surgeons who encounter it during the anterior approach to total hip arthroplasty, little is known about its anatomical features. The aim of this study was to review the anatomy of IC, and describe its' origin, insertion, blood supply, innervation, muscle fiber characteristics and size. The function, clinical relevance and comparative anatomy of IC were also appraised. METHODS: Using Evidence-Based Anatomy methodology, electronic databases were searched with the terms "iliocapsularis", "iliacus minor", "iliotrochantericus", and "ilioinfratrochantericus" to identify eligible studies. RESULTS: Six studies (n = 287 lower limbs) examining the anatomy of IC were included. The pooled prevalence (PP) of the IC was 98.7% (95% CI 96.5-100.0). It arises from the inferior facet of the anterior inferior iliac spine (AIIS) and attaches inferior to the lesser trochanter. Attached to the anteromedial capsule along its entire length, IC has the largest capsular contribution of any of the hip muscles (73.8 ± 27.3 × 16.1 ± 4.4 mm). Thus, it is an important landmark in anterior surgical approaches to the hip joint. CONCLUSION: The anatomy of IC is becoming more relevant with the increasing use of anterior approaches to hip surgery. With attachments to the AIIS, the lesser trochanter as well as the length of the capsule, this muscle is an important landmark in total hip arthroplasty. LEVEL OF EVIDENCE: Level V.

Rise and fall of total mesorectal excision with lateral pelvic lymphadenectomy for rectal cancer: an updated systematic review and meta-analysis of 11,366 patients.

The role of lateral lymph node dissection (LLND) during total mesorectal excision (TME) for rectal cancer is still controversial. Many reviews were published on prophylactic LLND in rectal cancer surgery, some biased by heterogeneity of overall associated treatments. The aim of this systematic review and meta-analysis is to perform a timeline analysis of different treatments associated to prophylactic LLND vs no-LLND during TME for rectal cancer. METHODS: A literature search was performed in PubMed, SCOPUS and WOS for publications up to 1 September 2020. We considered RCTs and CCTs comparing oncologic and functional outcomes of TME with or without LLND in patients with rectal cancer. RESULTS: Thirty-four included articles and 29 studies enrolled 11,606 patients. No difference in 5-year local recurrence (in every subgroup analysis including preoperative neoadjuvant chemoradiotherapy), 5-year distant and overall recurrence, 5-year overall survival and 5-year disease-free survival was found between LLND group and non LLND group. The analysis of post-operative functional outcomes reported hindered quality of life (urinary, evacuatory and sexual dysfunction) in LLND patients when compared to non LLND. CONCLUSION: Our publication does not demonstrate that TME with LLND has any oncological advantage when compared to TME alone, showing that with the advent of neoadjuvant therapy, the advantage of LLND is lost. In this review, the most important bias is the heterogeneous characteristics of patients, cancer staging, different neoadjuvant therapy, different radiotherapy techniques and fractionation used in different studies. Higher rate of functional post-operative complications does not support routinely use of LLND.

Laparoscopic surgery during the COVID-19 pandemic: detection of SARS-COV-2 in abdominal tissues, fluids, and surgical smoke.

BACKGROUND: There are still concerns over the safety of laparoscopic surgery in coronavirus disease 2019 (COVID-19) patients due to the potential risk of viral transmission through surgical smoke/laparoscopic pneumoperitoneum. METHODS: We performed a systematic review of currently available literature to determine the presence of severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) in abdominal tissues or fluids and in surgical smoke. RESULTS: A total of 19 studies (15 case reports and 4 case series) comprising 29 COVID-19 patients were included. The viral RNA was positively identified in 11 patients (37.9%). The samples that tested positive include the peritoneal fluid, bile, ascitic fluid, peritoneal dialysate, duodenal wall, and appendix. Similar samples, together with the omentum and abdominal subcutaneous fat, tested negative in the other patients. Only one study investigated SARS-COV-2 RNA in surgical smoke generated during laparoscopy, reporting negative findings. CONCLUSIONS: There are conflicting results regarding the presence of SARS-COV-2 in abdominal tissues and fluids. No currently available evidence supports the hypothesis that SARS-COV-2 can be aerosolized and transmitted through surgical smoke. Larger studies are urgently needed to corroborate these findings.

Prevalence and pubo-umbilical index of pyramidalis muscle in a select Kenyan population.

PURPOSE: Pyramidalis is a lower anterior abdominal wall muscle that is considered vestigial and shows variations in prevalence and size. It's been utilized as an anatomical landmark and harvested for use in various surgical procedures. Despite knowledge of its clinical importance, data on the prevalence of pyramidalis remain absent from the Kenyan population with few studies globally reporting on its pubo-umbilical index. We therefore aimed to determine the prevalence and relative lengths (pubo-umbilical index) of pyramidalis muscle in a sample Kenyan population. MATERIALS AND METHODS: Fifty-two cadavers (41 males, 11 females) from the Department of Human Anatomy, University of Nairobi were used. Prevalence and length of the muscle (l) were established, and the distance between pubic symphysis and umbilicus (L) measured and used to calculate pubo-umbilical index (l/L ×100%). Independent and paired T tests were done, using SPSS® version 22. A p value of ≤ 0.05 was considered statistically significant at a 95% confidence interval. RESULTS: Pyramidalis was present in 84% (44) of cadavers; 83% (43) bilaterally, 2% (1) unilaterally, and 85.4% (35) in males, 81.8% (9) in females. Mean length in males and females was 71.8 ± 35 mm and 63.5 ± 37.5 mm, respectively. Mean pubo-umbilical index was 38% ± 18 (39 % ± 18 males, 35% ± 19 females). No statistically significant difference was found. CONCLUSION: Pyramidalis is a highly prevalent muscle in the Kenyan population and, hence, could be exploited for its clinical and surgical utilities. The muscle terminates largely within the 2nd quarter (25-50%) of the infra-umbilical linea alba measured from pubic symphysis. Its pubo-umbilical index would be useful to surgeons making midline infra-umbilical incisions and performing procedures involving the muscle.

Surgical anatomy of the accessory middle colic artery: a meta-analysis with implications for splenic flexure cancer surgery.

AIM: Surgical resection of splenic flexure cancers (SFCs) is technically demanding due to the complex regional anatomy, characterized by the presence of embryological adhesions, close proximity to the pancreas and spleen, and a highly heterogeneous arterial supply and lymphatic drainage. The accessory middle colic artery (AMCA) is increasingly being recognized as an important source of blood supply to the splenic flexure. The aim of this study is to determine the prevalence and anatomical features of the AMCA. METHOD: A systematic search of the scientific literature was conducted on PubMed and Embase from inception to November 2020 to identify potentially eligible studies. Data were extracted and prevalence was pooled into a meta-analysis using MetaXL and Meta-Analyst software. RESULTS: A total of 16 studies (n = 2203 patients) were included. The pooled prevalence (PP) of the AMCA was 25.4% (95% CI 18.1-33.4). Its prevalence was higher in patients without a left colic artery (LCA) (PP = 83.2%; 95% CI 70.4-93.1). The commonest origin for the AMCA was the superior mesenteric artery (PP = 87.9%; 95% CI 86.4-90.7). The AMCA shared a common trunk/gave rise to pancreatic branches in 23.1% of cases (95% CI 15.3-31.9). CONCLUSION: The AMCA contributes to the vascularization of the splenic flexure in approximately 25% of individuals, and may be an important feeder artery to SFCs, especially in the absence of a LCA. Preoperative identification of this artery is important to ensure optimal surgery for SFC and minimize complications.