Can propensity score matching replace randomized controlled trials?

Randomized controlled trials (RCTs) have long been recognized as the gold standard for establishing causal relationships in clinical research. Despite that, various limitations of RCTs prevent its widespread implementation, ranging from the ethicality of withholding potentially-lifesaving treatment from a group to relatively poor external validity due to stringent inclusion criteria, amongst others. However, with the introduction of propensity score matching (PSM) as a retrospective statistical tool, new frontiers in establishing causation in clinical research were opened up. PSM predicts treatment effects using observational data from existing sources such as registries or electronic health records, to create a matched sample of participants who received or did not receive the intervention based on their propensity scores, which takes into account characteristics such as age, gender and comorbidities. Given its retrospective nature and its use of observational data from existing sources, PSM circumvents the aforementioned ethical issues faced by RCTs. Majority of RCTs exclude elderly, pregnant women and young children; thus, evidence of therapy efficacy is rarely proven by robust clinical research for this population. On the other hand, by matching study patient characteristics to that of the population of interest, including the elderly, pregnant women and young children, PSM allows for generalization of results to the wider population and hence greatly increases the external validity. Instead of replacing RCTs with PSM, the synergistic integration of PSM into RCTs stands to provide better research outcomes with both methods complementing each other. For example, in an RCT investigating the impact of mannitol on outcomes among participants of the Intensive Blood Pressure Reduction in Acute Cerebral Hemorrhage Trial, the baseline characteristics of comorbidities and current medications between treatment and control arms were significantly different despite the randomization protocol. Therefore, PSM was incorporated in its analysis to create samples from the treatment and control arms that were matched in terms of these baseline characteristics, thus providing a fairer comparison for the impact of mannitol. This literature review reports the applications, advantages, and considerations of using PSM with RCTs, illustrating its utility in refining randomization, improving external validity, and accounting for non-compliance to protocol. Future research should consider integrating the use of PSM in RCTs to better generalize outcomes to target populations for clinical practice and thereby benefit a wider range of patients, while maintaining the robustness of randomization offered by RCTs.

Prehabilitation programs in liver resection: a narrative review.

BACKGROUND AND OBJECTIVE: Liver resection (LR) is a commonly performed surgical procedure for the management of hepatocellular carcinoma and other liver conditions. Despite its benefits in providing patients a potential cure, it is also associated with significant postoperative complications and prolonged recovery periods. In recent years, pre-operative rehabilitation (prehabilitation) has emerged as an up-and-coming strategy to optimize patients' physical, psychological and functional status before LR, leading to improved surgical and patient postoperative outcomes. Hence, our review aims to explore and synthesize the existing literature on prehabilitation in LR to provide an overview of the current evidence to help guide physicians in managing their patients. METHODS: A comprehensive literature search was conducted in multiple electronic databases from inception to July 2023. The search strategy was tailored to capture studies investigating the role of prehabilitation in LR, and the factors that contribute to beneficial outcomes in the postoperative period. KEY CONTENT AND FINDINGS: Prehabilitation programs encompass a multifaceted approach to enhance surgical outcomes and patient well-being. This considers the specific needs of the varying patient populations, such as the elderly, or the cancer ridden. Improving physical fitness, nutritional supplementation and psychological support are the common tenets of prehabilitation. In physical prehabilitation, patients are engaged in intensive physical exercise often by means of a cycle ergometer. Addressing nutritional deficiencies through supplements and dietary interventions is also vital. Psychosocial assessments, advance care planning, music therapy, and progressive relaxation exercises are shown to enhance patient resilience and well-being. In addition, innovative approaches such as optimizing fluid balance, avoiding epidural analgesia, perioperative steroid administration, phosphate correction and branched-chain amino acid supplementation are being explored. CONCLUSIONS: Prehabilitation is important in optimizing patients before LR and is key in improving postoperative outcomes. Several prehabilitation strategies exist, but no formal consensus exists on patient selection and an ideal program.

Opisthorchis viverrini-Current Understanding of the Neglected Hepatobiliary Parasite.

Opisthorchiasis due to Opisthorchis viverrini infection continues to be a significant public healthcare concern in various subregions of Southeast Asia, particularly in Thailand, Laos, Cambodia, Myanmar, and Vietnam. The main mode of transmission is via consumption of raw or undercooked fish, which is deeply embedded in the culture and tradition of the people living near the Mekong River. After ingestion, the flukes migrate to the bile ducts, potentially causing many hepatobiliary complications, including cholangitis, cholecystitis, cholelithiasis, advanced periductal fibrosis and cholangiocarcinoma. Several mechanisms of opisthorchiasis-associated cholangiocarcinogenesis have been proposed and elucidated in the past decade, providing insight and potential drug targets to prevent the development of the sinister complication. The gold standard for diagnosing opisthorchiasis is still via stool microscopy, but the advent of novel serological, antigen, and molecular tests shows promise as more convenient, alternative diagnostic methods. The mainstay of treatment of opisthorchiasis is praziquantel, while treatment of opisthorchiasis-associated cholangiocarcinoma depends on its anatomic subtype and resectability. Thus far, the most successful fluke control programme is the Lawa model based in Thailand, which raised awareness, incorporated education, and frequent surveillance of intermediate hosts to reduce transmission of opisthorchiasis. Development of vaccines using tetraspanins shows promise and is currently ongoing.

Outcomes of an outpatient home-based prehabilitation program before pancreaticoduodenectomy: A retrospective cohort study.

Backgrounds/Aims: Prehabilitation aims for preoperative optimisation to reduce postoperative complications. However, there is a paucity of data on its use in patients undergoing pancreaticoduodenectomy (PD). Thus, this study aims to evaluate the outcomes of a home-based outpatient prehabilitation program (PP) versus no-PP in patients undergoing PD. Methods: This retrospective cohort study compared patients who underwent PP versus no-PP before elective PD from January 2016 to December 2020. Inclusion criteria for PP were < 65 years or 65-74 years with FRAIL score < 3. No-PP included dietician, case manager and anesthesia review. PP included additional physiotherapy sessions, caregiver training and interim phone consultation. Univariate and multivariate analysis were used to evaluate length of stay (LOS), morbidity, 30-day readmission, and 90-day mortality. Results: Seventy-one patients (PP: n = 50 [70.4%]; no-PP: n = 21 [29.6%]) were included in this study. Median age was 65 years (interquartile range [IQR]: 58-72 years). Majority (n = 58 [81.7%]) of patients underwent open surgery. Ductal adenocarcinoma was the most common histology (49.3%). Patient demographics were comparable between both groups. Overall median LOS was 11.0 days (IQR: 8.0-17.0 days). Compared to no-PP, PP was not independently associated with reduced intra-abdominal collections (odds ratio [OR]: 0.43; 95% confidence interval [CI]: 0.03-6.11, p = 0.532), major morbidity (OR: 1.31; 95% CI: 0.09-19.47; p = 0.845) or 30-day readmission (OR: 3.16; 95% CI: 0.26-38.27; p = 0.365). There was one (1.4%) 30-day mortality. Conclusions: Our outpatient PP with unsupervised exercise regimes did not improve postoperative outcomes following elective PD.

Paraneoplastic syndromes in hepatocellular carcinoma: a review.

INTRODUCTION: Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide, and a significant proportion (20-40%) of patients with HCC develop paraneoplastic syndromes (PNS). Despite this, there is a paucity of clinical evidence regarding PNS in HCC. AREAS COVERED: A systematic search was performed to identify relevant case studies regarding PNS in HCC. Another search was conducted to identify studies that evaluated the impact of PNS on survival outcomes in HCC. Since there are currently no international guidelines for PNS in HCC, this review aims to provide comprehensive summaries and recommendations of PNS in HCC, including the pathophysiology, clinical features, diagnostic approach, and management, so that clinicians remain guided in caring for HCC patients with PNS. In general, PNS are associated with poorer survival outcomes and negative prognostic markers of HCC. EXPERT OPINION: The presence of PNS has a significant influence on survival rates and clinical outcomes of patients with HCC. They contribute to significant morbidity, influencing patients' quality of life and fitness for curative and palliative therapies. Therefore, it is paramount for PNS to be integrated into routine investigations after diagnosing HCC to guide further management and prognostication of the disease.

Student assistantship programme: an evaluation of impact on readiness to transit from medical student to junior doctor.

BACKGROUND: Studies report that medical graduates are not prepared for practice as expected, and interventions have been developed to prepare them for practice. One such intervention is the assistantship, which provides hands-on opportunities to hone clinical skills and undertake responsibilities under supervision. The Lee Kong Chian School of Medicine (LKCMed) is Singapore's newest medical school, and students undergo a Student Assistantship Programme (SAP) to prepare for practice as junior doctors (PGY1). This study evaluated the SAP from the students' and clinical supervisors' perspectives. METHODS: Students completed online questionnaires to assess readiness for practice before and after SAP, and a subsample were interviewed about their experiences of SAP and its impact on their preparedness for PGY1. In addition, after our graduates had begun work as PGY1 doctors, their clinical supervisors completed an online questionnaire and were interviewed about the perceived benefits of SAP and the attributes of our graduates as junior doctors. RESULTS: Fifty (96%) students completed the pre-SAP questionnaire and 46 (92%) completed the post-SAP questionnaire. Levels of preparedness increased post-SAP (mean scores range pre-SAP: 2.38 to 4.32 vs post-SAP: 3.08 to 4.48); so did opportunities to undertake PGY1 duties (pre-SAP: 56% vs post-SAP: 96%), and hands-on experience in medical emergencies (pre-SAP: 76% vs post-SAP: 89%).Experience of acute care situations increased except "paracetamol overdose". Readiness to be first respondents in ten acute situations improved (statistically significant for asthma, chronic obstructive pulmonary disease exacerbation, gastrointestinal bleed, sepsis, and adverse drug reactions). Three themes emerged from twenty-five student interviews: learning about the work environment, opportunities to learn in a safe environment, and enhancing SAP for future students. Thirty-three supervisors completed the questionnaire, and 70% rated SAP positively in preparing students for PGY1. Eight supervisors interviewed shared positively about the content, timing, and duration of SAP; and suggested future SAPs help students to develop coping and reflective skills. CONCLUSIONS: The SAP improved students' preparedness and experience across clinical areas, and students felt the SAP helped bridge undergraduate curriculum and work, provided opportunities to hone their skills and learn from junior doctors. Most clinical supervisors rated the SAP effective in preparing students for PGY1. This is the first formal evaluation of an assistantship in Singapore, and the findings are encouraging from the perspective of students and PGY1 supervisors.

Adhesive small bowel obstruction - an update.

Small bowel obstruction (SBO) accounts for 12-16% of emergency surgical admissions and 20% of emergency surgical procedures. Even with the advent of laparoscopic surgery, intra-abdominal adhesions remain a significant cause of SBO, accounting for 65% of cases. History and physical examination are essential to identify signs of bowel ischemia as this indicates a need for urgent surgical exploration. Another critical aspect of evaluation includes establishing the underlying cause for obstruction and distinguishing between adhesive and non-adhesive etiologies as adhesive SBO (ASBO) can be managed non-operatively in 70-90% of patients. A patient with a history of abdominopelvic surgery along with one or more cardinal features of obstruction should be suspected to have ASBO until proven otherwise. Triad of severe pain, pain out of proportion to the clinical findings, and presence of an abdominal scar suggest possible closed-loop obstruction. Computed tomography has higher sensitivity and specificity compared to plain films and is recommended by the Bologna guidelines. Correcting fluid and electrolyte imbalance is an initial crucial step to mitigate severe hypovolemia. Patients should proceed with surgery if symptoms of bowel compromise are present, or if symptoms do not resolve or have worsened. Surgery is indicated in patients with ischemia, strangulation, perforation, peritonitis, or failure of non-operative treatment. With advances in minimal access technology and increasing experience, laparoscopic adhesiolysis is recommended. Mechanical adhesion barriers are an effective measure to prevent adhesion formation.

Pancreaticopleural Fistula Causing Massive Right Hydrothorax and Respiratory Failure.

Hydrothorax secondary to a pancreaticopleural fistula (PPF) is a rare complication of acute pancreatitis. In patients with a history of pancreatitis, diagnosis is made by detection of amylase in the pleural exudate. Imaging, particularly magnetic resonance cholangiopancreatography, aids in the detection of pancreatic ductal disruption. Management includes thoracocentesis and pancreatic duct drainage or pancreatic resection procedures. We present a case of massive right hydrothorax secondary to a PPF due to recurrent acute pancreatitis. Due to respiratory failure, urgent thoracocentesis was done. Distal pancreatectomy with splenectomy and cholecystectomy was performed. The patient remains well at one-year follow-up.

Laparoscopic common bile duct exploration: our first 50 cases.

INTRODUCTION: Laparoscopic common bile duct exploration (CBDE) is becoming more popular in the management of choledocholithiasis due to improved laparoscopic expertise and advancement in endoscopic technology and equipment. This study aimed to evaluate the safety and short-term outcome of laparoscopic CBDE in a single institution over a 3-year period. MATERIALS AND METHODS: A retrospective review of the records of all patients who underwent laparoscopic CBDE in Tan Tock Seng Hospital between January 2006 and September 2008 was conducted. RESULTS: Fifty consecutive patients, with a median age of 60 years (range, 27 to 85) underwent laparoscopic CBDE for choledocholithiasis during the study period. About half of our patients presented as an emergency with acute cholangitis (32.0%) accounting for the majority. A total of 22 (44.0%) patients underwent laparoscopic CBDE as their primary procedure while the remaining 28 (56.0%) were subjected to preoperative ERCP initially. Of the latter group, documented stone clearance was only documented in 5 (17.9%) patients. Laparoscopic CBDE via the transcystic route was performed in 27 (54.0%) patients while another 18 patients (36.0%) had laparoscopic choledochotomy and 1 patient (2.0%) had laparoscopic choledocho-duodenostomy. There were 4 (8.0%) conversions in our series. The median operative time for laparoscopic CBDE via the transcystic route and the laparoscopic choledochotomy were 170 (75-465) and 250 (160-415) minutes, respectively. For the 18 patients who underwent a laparoscopic choledochotomy, T-tube was inserted in 8 (44.4%) patients while an internal biliary stent was placed in 4 (22.2%) with the remaining 6 patients (33.3%) undergoing primary closure of the choledochotomy. The median length of hospital stay was 2 days (range, 1 to 15) with no associated mortality. The main complications (n = 4, 8.0%) included retained CBD stones and biliary leakage. These were treated successfully with postoperative endoscopic retrograde cholangiopancreatography (ERCP) with/without percutaneous drainage with no further surgery required. CONCLUSION: Laparoscopic CBDE is a safe operation with good outcome in managing choledocholithasis. Its dividends include the numerous benefits of minimally invasive surgery. If possible, transcystic extraction is preferred to choledochotomy, as this obviates the need for biliary diversion. ERCP will still hold an important role in certain instances in the management of choledocholithiasis.