Evaluation of Possible Association between Serum Levels of Aldosterone and Cortisol with Clinical Symptoms Progression in COVID-19 Suspicious Outpatients Tested for SARS-CoV2 RT-PCR: An Analytical Cross-Sectional Study

Aldosterone is a key component of Renin-Angiotensin-Aldosterone System (RAAS). The RAAS could play a substantial role in the pathophysiology of coronavirus disease 2019 (COVID-19). Moreover, the dynamics of the Hypothalamic-Pituitary-Adrenal (HPA) axis may have changed in COVID-19. Cortisol, as an important factor in assessing immune system activity, is an important part of this axis. The present study compared the serum levels of aldosterone and cortisol in COVID-19 outpatients with those of potentially non-infected participants. It was also aimed to assess the possible association between serum levels of aldosterone and cortisol with clinical symptoms progression in COVID-19 outpatients. Demographic characteristics (i.e., gender and age) and clinical data (i.e., oxygen saturation [SPO2], respiratory rate [RR], and heart rate) were collected. Serum cortisol and aldosterone measurements were conducted using the ELISA technique. Clinical symptoms of the positive polymerase chain reaction (PCR) group were followed up on for 28 days in weekly intervals. SPO2 was significantly lower in the positive PCR group; however, the RR was significantly higher (P=0.03 and P=0.001, respectively). Significantly higher levels of aldosterone were found in males of the negative PCR group, compared to females (P=0.05). Cortisol (OR=0.937, P=0.033) and aldosterone (OR=1.005, P=0.020) levels had a decreasing and increasing effect on the chances of respiratory symptoms occurring over time, respectively. Furthermore, over time, women were twice as likely as men to develop neurologic symptoms (OR=0.530, P=0.015). According to the findings of this study, cortisol and aldosterone are associated with the chance of respiratory symptoms occurring over time. However, the levels of these two markers do not seem to be related to the progression of clinical symptoms of lower grades of COVID-19.

Hemodynamic stress-induced cardiac remodelling is not modulated by ablation of phosphodiesterase 4D interacting protein

Adrenergic stimulation in the heart activates the protein kinase A (PKA), which phosphorylates key proteins involved in intracellular Ca²⁺ handling. PKA is held in proximity to its substrates by protein scaffolds, the A kinase anchoring proteins (AKAPs). We have previously identified the transcript of phosphodiesterase 4D interacting protein (Pde4dip; also known as myomegalin), one of the sarcomeric AKAPs, as being differentially expressed following hemodynamic overload, a condition inducing hyperadrenergic state in the heart. Here, we addressed whether PDE4DIP is involved in the adverse cardiac remodelling following hemodynamic stress. Homozygous Pde4dip knockout (KO) mice, generated by CRISPR-Cas9 technology, and wild-type (WT) littermates were exposed to aortocaval shunt (shunt) or transthoracic aortic constriction (TAC) to induce hemodynamic volume overload (VO) or pressure overload (PO), respectively. The mortality, cardiac structure, function and pathological cardiac remodelling were followed up after hemodynamic injuries. The PDE4DIP protein level was markedly downregulated in volume-overloaded- but upregulated in pressure-overloaded-WT hearts. Following shunt or TAC, mortality rates were comparably increased in both genotypes. Twelve weeks after shunt or TAC, Pde4dip-KO animals showed a similar degree of cardiac hypertrophy, dilatation and dysfunction as WT mice. Cardiomyocyte hypertrophy, myocardial fibrosis, reactivation of cardiac stress genes and downregulation of ATPase, Ca²⁺ transporting, cardiac muscle, slow twitch 2 transcript did not differ between WT and Pde4dip-KO hearts following shunt or TAC. In summary, despite a differential expression of PDE4DIP protein in remodelled WT hearts, Pde4dip deficiency does not modulate adverse cardiac remodelling after hemodynamic VO or PO.

Heat shock protein A4 ablation leads to skeletal muscle myopathy associated with dysregulated autophagy and induced apoptosis

BACKGROUND

Molecular chaperones assist protein folding, facilitate degradation of misfolded polypeptides, and thereby maintain protein homeostasis. Impaired chaperone activity leads to defective protein quality control that is implicated in multiple skeletal muscle diseases. The heat shock protein A4 (HSPA4) acts as a co-chaperone for HSP70. Previously, we showed that Hspa4 deletion causes impaired protein homeostasis in the heart. However, its functional role in skeletal muscle has not been explored.

METHODS

We performed a comparative phenotypic and biochemical analyses of Hspa4 knockout (KO) mice with wild-type (WT) littermates.

RESULTS

HSPA4 is markedly upregulated in regenerating WT muscle in vivo, and in differentiated myoblasts in vitro. Hspa4-KO mice are marked by growth retardation and increased variability in body weight, accompanied by 35% mortality rates during the peri-weaning period. The surviving Hspa4-KO mice experienced progressive skeletal muscle myopathy, characterized by increased number of muscle fibers with centralized nuclei, heterogeneous myofiber size distribution, inflammatory cell infiltrates and upregulation of embryonic and perinatal myosin heavy chain transcripts. Hspa4-KO muscles demonstrated an accumulation of autophagosome-associated proteins including microtubule associated protein1 light chain 3-II (LC3-II) and p62/sequestosome accompanied by increased number of TUNEL-positive nuclei.

CONCLUSIONS

Our findings underscore the indispensable role of HSPA4 in maintenance of muscle integrity through contribution in skeletal muscle autophagy and apoptosis, which might provide a novel therapeutic strategy for skeletal muscle morbidities.

871 Liver Transplant for Colorectal Liver Metastases: A Systematic Review and Meta-Analysis of Proportions

Introduction

Colorectal liver metastases were historically considered a contraindication to liver transplantation, but dismal outcomes for those with metastatic colorectal cancer and advancements in liver transplantation (LT) have led to a renewed interest in the topic. We aim to compare the current evidence for liver transplantation for non-resectable colorectal liver metastases (NRCLM) with the current standard treatment of palliative chemotherapy reported in literature – 5-year survival rate <10%.

Method

A systematic review and meta-analysis of proportions was conducted following screening of MEDLINE, EMBASE, SCOPUS and CENTRAL for studies reporting liver transplantation for colorectal liver metastases. Post-operative outcomes measured included 1-, 3- and 5-year survival, overall survival, disease-free survival, and complication rates.

Results

Three non-randomised studies met the inclusion criteria, reporting a total of 48 patients receiving LT for NRCLM. Survival at 1-, 3- and 5-years was 83.3-100%, 58.3-80% and 50-80% respectively with no significant difference detected (p = 0.22, p = 0.48, p = 0.26). Disease free survival was 35-56% with the most common site of recurrence being lung. Thirteen out of fourteen deaths were due to disease recurrence.

Conclusions

Although current evidence suggests a survival benefit conferred by LT in NRCLM compared to palliative chemotherapy, the ethical implications of organ availability and allocation demand rigorous justification. Eight registered clinical trials will report on 300 more patients undergoing LT for NRCLM over the next 10 years: concomitant improvements in the management of patients following liver resection and of palliative chemotherapy regimens is paramount.

812 Mortality Risk prediction in Emergency Laparotomy (ORIEL) Study Outcomes at Wythenshawe Hospital

Aim

Emergency laparotomy is a high-risk procedure with significant morbidity and mortality. ORIEL is a multi-centre national study aiming to compare the 30-day mortality predictions generated by NELA, P-POSSUM, ACS-NSQIP and SORT risk calculators with observed 30-day mortality rates in patients undergoing emergency laparotomies. We present the data collected from Wythenshawe hospital.

Method

Data were collected retrospectively on adult patients undergoing an emergency laparotomy between 01/12/2017 to 30/11/2019 at Wythenshawe hospital from the online NELA database. The median pre-operative mortality risks were calculated using the four risk calculators for all patients. Mortality and morbidity were compared with data reported in the Sixth NELA report.

Results

The median predicted pre-operative mortality (IQR) for all patients studied using NELA, P-POSSUM, ACS-NSQIP and SORT were: 4.3 (13.0), 5.2 (14.2), 3.4 (8.2) and 2.9 (9.3) respectively. Among patients who were alive 30 days post-operatively, the median predicted mortalities (IQR) were: 3.8 (8.5), 4.8 (11.0), 2.6 (6.9) and 2.8 (7.1) respectively, and among those who died were: 30.8 (18.9), 30.3 (63.4), 16.9 (13.9) and 20.3 (16.2). Compared to the national average, mortality rates at Wythenshawe were lower (9% v 9.3%), the median length of stay in hospital was lower (12 days v 15.4 days) and the percentage of high-risk patients admitted to critical care was higher (93% v 85%).

Conclusions

Similar values were generated with all the scoring systems among all patients. Wythenshawe hospital reports lower mortality rates and shorter stays in hospital despite operating on higher risk patients (ASA grades 3-5).

715 The Importance of Social Media to The Academic Surgical Literature: Relationship Between Twitter Activity and Readership Metrics

Aim

Social media (SoMe) has an increasing role within professional surgical practice, including the publishing and engagement of academic literature. This study aims to analyse the relationship between social media use and traditional and alternative metrics amongst academic surgical journals.

Method

Journals were identified through the InCites Journal Citation Reports 2019, and their impact factor (IF), h-index and CiteScore were noted. Social media platforms were examined, and Twitter activity interrogated between 1st January- 31st December 2019. Healthcare Social Graph (HSG) score and an aggregated Altmetric score were also calculated for each journal. Statistical analysis was carried out to look at the correlation between traditional metrics, Twitter activity and altmetrics.

Results

Journals with higher IF were more likely to use a greater number of SoMe platforms (R2=0.648; p < 0.0001). Journals with dedicated Twitter profiles had a higher IF than journals without (median, 2.96 vs 1.88; MWU=390; p < 0.001) however over a one-year period (2018-2019) having a twitter presence did not alter IF (MWU=744.5; p = 0.885). Increased Twitter activity was positively correlated with IF. Longitudinal analysis over six years suggested cumulative tweets correlated with an increased IF (R2=0.324, p = 0.004). Novel alternative measures including HSG score (R2=0.472, p = 0.005) and Altmetric score (R2=0.779, p = 0.001) positively correlated with IF.

Conclusions

Higher IF is associated with SoMe presence and activity, particularly on Twitter, with long term activity being of particular importance. Modern alternative metrics correlate with IF. This relationship is complex and future studies should look to understand this further.

720 Pringle Versus Selective Hepatic Vascular Exclusion in Major Hepatectomy: A Systematic Review and Meta-Analysis

Aim

Mortality and morbidity following hepatic resection is significantly affected by major intra-operative blood loss. Multiple techniques have been developed in an attempt to minimise blood loss by occluding hepatic inflow and outflow. This systematic review and meta-analysis evaluates whether selective hepatic vascular exclusion compared to a Pringle manoeuvre in hepatic resection reduces rates of morbidity and mortality.

Method

A systematic review and meta-analysis were conducted according to the PRISMA guidelines by screening EMBASE, MEDLINE/PubMed, CENTRAL, SCOPUS and bibliographic reference lists for comparative studies meeting the predetermined inclusion criteria. Intra- and post-operative outcome measures were investigated. Pooled odds ratios or mean differences with 95% confidence intervals were calculated using either fixed- or random-effects models.

Results

Five studies were identified including two randomized controlled trials and three observational studies reporting a total of 2,198 patients. Data synthesis showed significantly decreased rates of mortality, overall complications, patients requiring blood transfusion, air embolism, warm ischaemia time, liver failure and multi-organ failure when performing SHVE compared to a Pringle manoeuvre. Rates of hepatic vein rupture and post-operative haemorrhage remained the same. Performing SHVE resulted in a significantly longer operation time.

Conclusions

Performing SHVE in major hepatectomy may result in reduced rates of morbidity and mortality when compared to a Pringle manoeuvre, although may prolong operating time. The results of this meta-analysis are based on a few high-quality studies where tumours were adjacent to major vessels. Further RCTs are required to validate these results and determine the best technique for hepatic vascular control in this patient cohort.

717 Roux-En-Y Versus Single Loop Reconstruction in Pancreaticoduodenectomy: A Systematic Review and Meta-Analysis

Aim

Post-operative pancreatic fistula (POPF) and delayed gastric emptying (DGE) both remain problematic complications following pancreaticoduodenectomy. This systematic review and meta-analysis evaluates whether Roux-en-Y compared to a single loop reconstruction in pancreaticoduodenectomy significantly reduces rates of these complications.

Method

A systematic review and meta-analysis were conducted according to the PRISMA guidelines by screening EMBASE, MEDLINE/PubMed, CENTRAL and bibliographic reference lists for comparative studies meeting the predetermined inclusion criteria. Post-operative outcome measures included: POPF, DGE, bile leak, operating time, blood loss, need for transfusion, wound infection, intra-abdominal collection, post-pancreatectomy haemorrhage, overall morbidity, re-operation, overall mortality, hospital length of stay. Pooled odds ratios or mean differences with 95% confidence intervals were calculated using either fixed- or random-effects models.

Results

Fourteen studies were identified including four randomized controlled trials (RCTs) and 10 observational studies reporting a total of 2 031 patients. Data synthesis showed no statistically significant difference between the two groups in any of the outcome measures except operating time, which was longer in those undergoing Roux-en-Y reconstruction.

Conclusions

Roux-en-Y is not superior to single loop reconstruction in pancreaticoduodenectomy but may prolong operating time. Future high-quality randomized studies with appropriate study design and sample size power calculation may be required to further validate this conclusion.