Strategies to improve survival outcomes of out-of-hospital cardiac arrest (OHCA) given a fixed budget: A simulation study.

BACKGROUND: Our study aimed to identify a strategy that maximizes survival upon hospital discharge or 30-days post out-of-hospital cardiac arrest (OHCA) in Singapore for fixed investments of S$1, S$5, or S$10 million. Four strategies were compared: (1) no additional investment; (2) reducing response time via leasing of more ambulances; (3) increasing number of people trained in cardiopulmonary resuscitation (CPR); and (4) automated external defibrillators (AED). METHODS: We estimated the effect of ambulance response time, bystander CPR and AED on survival based on Singapore's 2010-2015 OHCA registry data. We simulated the changes in ambulance response times and likelihood of (1) CPR and (2) AED usage as a function of their increased availability, which was then combined with the effect of each factor to determine the increase in survival for each strategy. RESULTS: Survival given no additional investment was 4.03% (95% CI: 3.96%, 4.10%). The investments in ambulances, CPR training and AEDs for a given budget of S$1M changed survival to 4.03% (95% CI: 3.96%, 4.10%), 4.04% (95% CI: 3.98%, 4.11%), and 4.44% (95% CI: 4.35%, 4.54%), respectively. This generated 0, 2 and 102 additional life years saved respectively. Given a budget of S$5M or S$10M, 509 or 886 additional life years could be saved, by investing in an additional 10,000 or 20,000 AEDs respectively. The strategies reached a saturation effect whereby improvement in survival was marginal when the budget was increased to ≥S$5M for investment in ambulances and CPR training. CONCLUSIONS: Investing in AEDs had the most gain in survival.

Global resuscitation alliance utstein recommendations for developing emergency care systems to improve cardiac arrest survival.

INTRODUCTION: The Global Resuscitation Alliance (GRA) was established in 2015 to improve survival for Out- of-Hospital Cardiac Arrest (OHCA) using the best practices developed by the Seattle Resuscitation Academy. However, these 10 programs were recommended in the context of developed Emergency Care Systems (ECS). Implementing these programs can be challenging for ECS at earlier stages of development. We aimed to explore barriers faced by developing ECS and to establish pre-requisites needed. We also developed a framework by which developing ECS may use to build their emergency response capability. METHOD: A consensus meeting was held in Singapore on 1st-2nd August 2017. The 74 participants were key stakeholders from 26 countries, including Emergency Medical Services (EMS) directors, physicians and academics, and two Physicians who sit on the World Health Organisation (WHO) panel for development of Emergency Care Systems. Five discussion groups examined the chain of survival: community, dispatch, ambulance and hospital; a separate group considered perinatal resuscitation. Discussion points were voted upon to reach a consensus. RESULTS: The answers and discussion points from each groupwere classified into a table adapted from WHO's framework of development for Emergency Services. After which, it was used to construct the modified survival framework with the chain of survival as the backbone. Eleven key statements were then derived to describe the pre-requisites for achieving the GRA 10 programs. The participants eventually voted on the importance and feasibility of these 11 statements as well as the GRA 10 programs using a matrix that is used by organisations to prioritise their action steps. CONCLUSION: In this paper, we propose a modified framework of survival for developing ECS systems. There are barriers for developing ECS systems to improve OHCA survival rates. These barriers may be overcome by systematic prioritisation and cost-effective innovative solutions.

Management of concurrent thoracic and abdominal aortic aneurysms.

Concurrent thoracic and abdominal aortic aneurysm is uncommon. It remains a formidable surgical challenge to vascular surgeons, as decision to treat in staged or simultaneous setting still debatable. We present, here, a case of a 62-year-old-man with asymptomatic concurrent thoracic and abdominal aortic aneurysms, which was successfully treated with two-stage hybrid endovascular repair. The aim of this case report is to discuss the treatment options available, possible associated complications and measures to prevent them.

Total percutaneous endovascular aneurysm repair (pEVAR): the initial experience in Hospital Kuala Lumpur.

INTRODUCTION: There has been a paradigm shift in the treatment of AAA with the advent of endovascular aneurysm repair (EVAR). Rapid progress and evolution of endovascular technology has brought forth smaller profile devices and closure devices. Total percutaneous endovascular aneurysm repair (pEVAR) involves the usage of suture-mediated closure devices (SMCDs) at vascular access sites to avoid a traditional surgical cutdown. MATERIALS AND METHODS: We retrospectively reviewed our experience of pEVAR between April 2013 and July 2014. Primary success of the procedure was defined as closure of a common femoral artery (CFA) arteriotomy without the need for any secondary surgical or endovascular procedure within 30 days. RESULTS: In total there were 10 pEVAR cases performed in the study period, one case in Queen Elizabeth Hospital during visiting vascular service. Patients have a mean age of 73.4 year old (66-77 year old) The mean abdominal aortic size was 7.2 cm (5.6-10.0cm). Mean femoral artery diameter was 9.0 mm on the right and 8.9 mm on the left. Mean duration of surgery was 119 minutes (98- 153 minutes). 50% of patients were discharged at post-operative day one, 30%- day two and 20%- day three. Primary success was achieved in 9 patients (90%) or in 19 CFA closures (95%). No major complication was reported. DISCUSSION: We believe that with proper selection of patients undergoing EVAR, pEVAR offers a better option of vascular access with shorter operative time, less post- operative pain, shorter hospital stay and minimises the potential complications of a conventional femoral cutdown.

Idiopathic Internal Thoracic Artery (ITA) Pseudoaneurysm treated with Endovascular Embolization.

A 44-year-old female was diagnosed with an ITA pseudoaneurysm in the right supraclavicular fossa. She was successfully treated with endovascular embolization. The challenges of diagnosis and treatment are discussed.

Mechanistic Studies on the Self-Assembly of PLGA Patchy Particles and Their Potential Applications in Biomedical Imaging.

Currently, several challenges prevent poly(lactic-co-glycolic acid) (PLGA) particles from reaching clinical settings. Among these is a lack of understanding of the molecular mechanisms involved in the formation of these particles. We have been studying in depth the formation of patchy polymeric particles. These particles are made of PLGA and lipid-polymer functional groups. They have unique patch-core-shell structural features: hollow or solid hydrophobic cores and a patchy surface. Previously, we identified the shear stress as the most important parameter in a patchy particle's formation. Here, we investigated in detail the role of shear stress in the patchy particle's internal and external structure using an integrative experimental and computational approach. By cross-sectioning the multipatch particles, we found lipid-based structures embedded in the entire PLGA matrix, which represents a unique finding in the PLGA field. By developing novel computational fluid dynamics and molecular dynamics simulations, we found that the shear stress determines the internal structure of the patchy particles. Equally important, we discovered that these particles emit a photoacoustic (PA) signal in the optical clinical imaging window. Our results show that particles with multiple patches emit a higher PA signal than single-patch particles. This phenomenon most likely is due to the fact that multipatchy particles absorb more heat than single-patchy particles as shown by differential scanning calorimetry analysis. Furthermore, we demonstrated the use of patchy polymeric particles as photoacoustic molecular probes both in vitro and in vivo studies. The fundamental studies described here will help us to design more effective PLGA carriers for a number of medical applications as well as to accelerate their medical translation.

Popliteal artery pseudoaneurysm successfully treated with amplatzer vascular plug.

Popliteal artery pseudoaneurysm is uncommon. They usually result from penetrating or blunt trauma, arterial reconstructive surgery, invasive diagnostic or surgical orthopedic procedures. They can cause arterial thrombosis and limb ischeamia. We report a 53 year old Chinese gentleman with popliteal artery pseudoaneurysm who presented with right lower limb numbness and paralysis in toes extension. He gave a history of acupuncture treatment around the popliteal fossa of the affected limb. Clinical examination revealed a pulsatile mass in the popliteal fossa. Computed tomography angiography showed a large, 5 cm, pseudoaneurysm arising from the popliteal artery. A diagnostic angiogram was performed and revealed that there is no run off from the popliteal artery and the tibial vessels were reconstructed from collaterals. Endovascular intervention was carried out with an Amplatzer Vascular Plug to embolise the pseudoaneurysm. The pseudoaneurysm was successfully excluded and post-op follow up revealed no more pulsatile mass and improving lower limb function. To the best of our knowledge this is first reported case of pseudoaneurysm of the popliteal artery secondary to acupuncture in Malaysia.

Effectiveness of a new standardised Urinary Continence Physiotherapy Programme for community-dwelling older women in Hong Kong.

OBJECTIVE: To examine the effectiveness of a standardised Urinary Continence Physiotherapy Programme for older Chinese women with stress, urge, or mixed urinary incontinence. DESIGN: A controlled trial. SETTING: Six elderly community health centres in Hong Kong. PARTICIPANTS: A total of 55 women aged over 65 years with mild-to-moderate urinary incontinence. INTERVENTIONS: Participants were randomly assigned to the intervention group (n=27) where they received eight sessions of Urinary Continence Physiotherapy Programme for 12 weeks. This group received education about urinary incontinence, pelvic floor muscle training with manual palpation and verbal feedback, and behavioural therapy. The control group (n=28) was given advice and an educational pamphlet on urinary incontinence. RESULTS: There was significant improvement in urinary symptoms in the intervention group, especially in the first 5 weeks. Compared with the control group, participants receiving the intervention showed significant reduction in urinary incontinence episodes per week with a mean difference of -6.4 (95% confidence interval, -8.9 to -3.9; t= -5.3; P<0.001) and significant improvement of quality of life with a mean difference of -3.93 (95% confidence interval, -5.08 to -2.78; t= -6.9; P<0.001) measured by Incontinence Impact Questionnaire Short Form modified Chinese (Taiwan) version. The subjective perception of improvement, measured by an 11-point visual analogue scale, was markedly better in the intervention group (mean, 8.7; standard deviation, 1.0; 95% confidence interval, 8.4-9.1) than in the control group (mean, 1.4; standard deviation, 0.7; 95% confidence interval, 1.2-1.7; t=33.9; P<0.001). The mean treatment satisfaction in the intervention group was 9.5 (standard deviation, 0.8) as measured by an 11-point visual analogue scale. CONCLUSIONS: This study demonstrated that the Urinary Continence Physiotherapy Programme was effective in alleviating urinary symptoms among older Chinese women with mild-to-moderate heterogeneous urinary incontinence.

Prevalence of Peripheral Arterial Disease and Abdominal Aortic Aneurysm among Patients with Acute Coronary Syndrome.

INTRODUCTION: Peripheral arterial disease(PAD) and abdominal aortic aneurysm(AAA) are two important underdiagnosed vascular pathologies. As they share common risk factors with coronary arterial disease, we conducted a study to look at their prevalence among patients with acute coronary syndrome(ACS). MATERIALS AND METHODS: Patients with ACS admitted to Queen Elizabeth Hospital, Malaysia, from February 2009 till August 2009 were screened prospectively for PVD and AAA. Patients' data and clinical findings were gathered and analyzed. Measurements of ankle brachial index (ABI) and abdominal aortic diameter were performed by a single assessor. PAD was defined as ABI ≤ 0.9 or diabetic patients with signs and symptoms of PAD and absence of pedal pulses. AAA was defined as abdominal aortic diameter ≥ 3cm. RESULTS: 102 patients were recruited with mean age of 59.5 years old. Male: female ratio was 6:1. 40.2% of patients had NSTEMI; 45.1%, STEMI and 14.7%, unstable angina. Risk factors profile is as follows: hypertension- 68.6%, smoking- 56.9%, hypercholesterolemia- 52.9%, diabetes mellitus- 35.3% and history of stroke- 5.9%. Median ABI was 1.1 with lowest reading of 0.4. Mean abdominal aortic size was 2.0cm with largest diameter of 3.3cm. PAD was present in 24.5% of patients and AAA in 2.0%. 68.0% of patients with PAD were asymptomatic. Smoking and age more than 60 years were independent predictors for PAD among ACS patients. CONCLUSIONS: PAD is strongly correlated with CAD with old age and smoker as independent predictors. However, association between AAA and ACS could not be established.

Tuberculosis of gallbladder with candidiasis, a rare entity.

Gallbladder tuberculosis (GT) is an extremely rare condition. This is thought to be due to the protective property of bile against the infection. Clinical and radiological diagnosis of GT is difficult. We describe a case of GT who initially presented to us with jaundice, a right hypochondrial mass and computed tomographic findings suggestive of gallbladder empyema. Diagnosis was made from histopathological examination of the resected gallbladder which revealed epitheloid granulomas with caseating necrosis and presence of Langhan's giant cells. From a literature search and to the best of our knowledge, this is the first GT to be reported in South East Asia.

Bystander CPR and survival.

Despite years of medical advances, bystander cardiopulmonary resuscitation (CPR) remains the most important factor in the saving of out-of-hospital cardiac arrest victims. However, the prevalence of bystander CPR remains low. New international recommendations, which aim to increase bystander CPR prevalence, allow for hands-only CPR under certain circumstances. More should be done to increase the awareness and training of CPR in Singapore as well as encourage the public to perform bystander CPR.

Quality of resuscitation in hospitals.

There is relatively less literature available on in-hospital cardiac arrest (IHCA) as opposed to that of out-of-hospital cardiac arrest (OHCA). Although IHCA and OHCA patients may differ at baseline, they share similar factors that are associated with survival. Important variables need to be standardised for reporting. Principles such as the 'chain of survival' remain applicable in the response. Early escalation protocols and medical emergency teams, together with streamlined activation pathways and staff training, are crucial. Post-resuscitation care bundles should be implemented.

Trends of breast cancer treatment in Sabah, Malaysia: a problem with lack of awareness.

INTRODUCTION: Sabah, formerly known as North Borneo, is part of East Malaysia. 52.2 percent of patients with breast cancer in Sabah presented at advanced stages and up to 20.4 percent of patients defaulted proper treatment, opting for traditional therapy. We performed a two-year prospective study looking at the treatment trends of breast cancer in Sabah. METHODS: Our subjects were all newly-diagnosed breast cancer cases seen at the hospital in 2005 and 2006. Type of surgery, chemotherapy, radiotherapy, hormonal therapy and surgical complication for each patient were studied. RESULTS: Out of 186 newly-diagnosed cases, 152 (81.7 percent) had surgery, 126 (67.7 percent) had chemotherapy, 118 (63.4 percent) had radiotherapy and 92 (49.5 percent) had hormonal therapy. 18.3 percent did not have surgery either due to refusal of treatment or advanced disease. They were more likely to be non-Chinese (91.1 percent, p-value is 0.02). Only 15.8 percent had breast-conserving surgery. The most frequent surgical complication was seroma formation (15.0 percent) . The commonest chemotherapy regime and hormonal therapy were anthracycline-based regime (88.1 percent) and tamoxifen (95.8 percent), respectively. CONCLUSION: The proportion of breast-conserving surgery and usage of modern adjuvant therapies are low in Sabah. This can be attributed to lack of breast cancer awareness leading to late presentation and refusal of treatment, coupled with insufficient health service funding.

Successful endovascular treatment of post-traumatic inferior pancreaticoduodenal artery pseudoaneurysm.

True and pseudoaneurysms of the visceral arteries are uncommon. They represent 0.1-0.2 percent of all vascular aneurysms. Visceral artery aneurysms (VAAs) should be treated due to their propensity to rupture and associated high mortality. We describe a 58-year-old man with pseudoaneurysm of the inferior pancreaticoduodenal artery and who presented with post-motor vehicle accident abdominal pain and a pulsatile epigastic mass. Computed tomography (CT) showed a pseudoaneurysm of the visceral artery, and selective mesenteric angiography showed the aneurysm to be arising from the inferior pancreaticoduodenal artery. The aneurysm was successfully treated with endovascular coil embolisation. CT angiogram at one month post-procedure revealed persistent occlusion of the aneurysm. To the best of our knowledge, this is the first reported pseudoaneurysm of inferior pancreaticoduodenal artery secondary to blunt abdominal trauma from a motor vehicle accident and also the first reported VAA from Malaysia.

Synchronous adenocarcinoma of caecum, transverse colon and jejunum.

Synchronous cancers are defined as malignant tumours that occur simultaneously, each of which must be distinct with no possibility of one being the metastasis of the other. A 65 year old gentleman presented to us with two month history of epigastric pain associated with anaemia, loss of appetite and weight. He has no history of malignancy in his family. Colonoscopy revealed tumours at transverse colon and caecum. Intra-operatively, tumours were sited at caecum, transverse colon and jejunum. Tumours were diagnosed as synchronous adenocarcinoma histopathologically with loss of expression of MLH1 and MSH2. From literature search, this is the first reported triple synchronous tumours of the caecum, transverse colon and jejunum. We believe that this gentleman developed triple synchronous tumour through the sporadic MSI pathway.

Circadian rhythm in cardiac arrest: the Singapore experience.

INTRODUCTION: There appears to be a circadian rhythm in the timing of cardiovascular and neurovascular events. The majority of studies have been conducted in western populations. This is the first study to look at the peaks and distribution of out-of-hospital cardiac arrest (OHCA) patients in Singapore. METHODS: The Cardiac Arrest and Resuscitation Epidemiology Studies I and II were prospective observation studies on OHCA in Singapore from October 1, 2001 to October 14, 2004. This study analysed data for patients older than 16 years. All data was collected and recorded as per the Utstein style template. Analysis was done for each of the quadrants of the 24-hour clock: 0001-0600, 0601-1200, 1201-1800 and 1801-2400 hours. RESULTS: Of the 2,428 cases, 2,167 OHCA patients qualified for the final analysis. Their mean ages were in the 60s for all the four quadrants, with a male predominance. The two peaks noted were at 0800 and 1900 hours for cardiac causes of death (n = 1,591), and at 0900 and 2000 hours for non-cardiac causes of death (n = 576). At all times of the day, the majority of OHCA occurred in residences and the bystander cardiopulmonary resuscitation rate ranged from 14.6 to 24.3 percent in the different quadrants of the day. CONCLUSION: OHCA has a bimodal distribution in our local cohort of patients. The information obtained will be utilised for fine-tuning emergency medical services strategies, as we strive to improve our current survival rates for OHCA.

Maximal motor unit discharge rates in the quadriceps muscles of older weight lifters.

UNLABELLED: Although the existence of "neural factors" is regularly cited as an important contributor to muscular strength, we have little specific knowledge regarding the existence of such neural factors or how they contribute to the expression of muscular force. PURPOSE: The present investigation sought to assess maximal motor unit discharge rates in older, highly resistance-trained adults to determine whether maximal motor unit discharge rates might be one such neural contributor to maximal strength production. METHODS: Subjects consisted of seven well-trained older weight lifters (ages 67-79 yr) and five untrained age-matched older adults. While subjects performed 50 and 100% maximal voluntary knee extensor contractions (MVC), recordings from groups of motor units were obtained from the rectus femoris muscle by using an indwelling electrode. Off-line analysis was performed to identify individual motor unit firing occurrences and to compute maximal motor unit discharge rates. RESULTS: As expected, knee extension strength in the trained weight lifters (367.0 +/- 72.0 N) was significantly greater than that in the control subjects (299.9 +/- 35.9 N; P < 0.05). Motor unit discharge rates were similar in the two subject groups at the 50% MVC force level (P > 0.05), but maximal (100% MVC) motor unit discharge rate in the weight lifters (23.8 +/- 7.71 pps) was significantly greater than that in the age-matched controls (19.1 +/- 6.29 pps; P < 0.05). CONCLUSION: Motor unit discharge rates may comprise an important neural factor contributing to maximal strength in older adults.

Impact of an aggressive stenting strategy on initial and one-year follow-up costs in patients undergoing coronary angioplasty.

BACKGROUND: Although stents have been shown in randomised trials to reduce restenosis rates compared with balloon angioplasty, there are concerns regarding the cost-effectiveness of an aggressive stenting strategy. Stents were shown to increase medical costs over 12 months in the early trials. AIM: Our aim was to determine the economic impact of an aggressive stenting strategy using current stenting techniques compared with a conservative stenting strategy. METHODS: Initial and one year follow-up costs were determined in all patients who underwent successful revascularisation during June to December 1996 (aggressive stenting, n = 401), and compared to all patients treated in the corresponding months in 1995 (conservative stenting, n = 347). All patients had clinical follow-up for one year. RESULTS: The proportion of patients receiving a stent increased from 22.5% in 1995 to 66.1% in 1996 (p < 0.0001). Requirement for repeat procedures in the 1995 group compared with 1996 was coronary angiography in 31% vs 16% (p < 0.001), coronary angioplasty in 11% vs 6% (p = 0.0044) and bypass surgery in 4.8% vs 2.5% (p = 0.054). The mean initial cost of the procedure was higher in the aggressive stenting group ($4319 +/- 1276 in 1995 vs $5131 +/- 1491 in 1996, p < 0.0001), but after 12 months follow-up, total medical costs were equivalent ($5975 +/- 4143 in 1995 vs $5994 +/- 3476 in 1996, p = NS). CONCLUSION: An aggressive coronary stenting strategy is associated with higher initial costs compared with a conservative strategy, but lower costs during follow-up due to reduced need for repeat procedures, resulting in equivalent one year total medical costs.

Validation of intratracheal instillation as an alternative for aerosol inhalation toxicity testing.

In collecting inhalation toxicity data for the evaluation of the health hazard from occupational exposure to the aerosols of a drug or a chemical, the determination of the inhaled dose in relation to the animal response is most desirable. Intratracheal administration is most likely to deliver an exact dose of a compound to the lungs of an experimental animal. In a series of tests, microliter (microl) quantities of a solution or a suspension of a test material were nebulized into the trachea of an anesthetized rat using an intratracheal fast instillation (ITFI) method. The dose-response in terms of the minimal effective dose (MED) and the median lethal dose (LD50) were determined. The ITFI dose-response for four drugs, five chemicals or chemical intermediates and four pesticides were compared with those obtained via inhalation (IH) and ingestion (p.o.). In addition, the dose-responses of the four pesticides were compared with two additional parameters, intranasal instillation (IN) and intravenous injection (i.v.). The MED end-points for studies via the respiratory administration route were no pharmacotoxic signs other than transient respiratory rales and/or dyspnea and no gross lesions, whereas those for the intranasal, oral and the intravenous administration routes were transient and slight body weight loss and no pharmacotoxic signs and/or gross lesions. The MED ratios between ITFI, IH and p.o. were 1 : 9.3+/-6.5 : 201.4+/-133.3, respectively, for the drugs, chemicals and chemical intermediates. The MED ratios for ITFI, IH, IN, i.v. and p.o. for the four pesticides were 1 : 2.2+/-1.4 : 2.1+/-1.3 : 1.1+/-0.7 : 1.4+/-0.9. The MED ratios for the two categories of test materials were fairly consistent between different routes of administration. Thus, the ITFI dose can be used for extrapolating the IH dose. The simplicity of the ITFI procedure and its requirement of only microliters of a compound to generate a meaningful and reliable dose-response suggests that ITFI may be an alternative method for acute inhalation toxicity evaluation of materials that may present inhalation hazards from liquid or solid aerosols.

Quantitative morphometric analysis of pulmonary deposition of aerosol particles inhaled via intratracheal nebulization, intratracheal instillation or nose-only inhalation in rats.

The effectiveness of three techniques to deliver a diazo dye suspension into the lungs of rats was compared. The intratracheal nebulization (ITN) technique delivered 10 microl of the suspension per 5-ml puff of air in 10 puffs as an aerosol. The intratracheal fast instillation (ITFI) technique delivered 100 microl of the suspension in a single 2-ml puff of air as droplets. The nose-only inhalation (NI) technique aerosolized the suspension at an analytical concentration that provided a calculated dose equivalent to 100 microl of the suspension in a 2-h inhalation period. Immediately after dosing, all the rats were killed by exsanguination. The trachea was tied and the lung was inflated in situ with air. After fixation, 5-microm thick slices were prepared from each lobe of the lung at a plane perpendicular to the axis of the lobar bronchus at levels proximal, medial and distal to the hilus. The numbers of bronchi, bronchioli and alveolar ducts within four ranges of diameters and the proportion of each selected area of lung tissue with and without dye particles were quantified using electronic imaging analyzers. The results indicated that ITN and ITFI dispersed the particles evenly throughout most of the airways and in patches in the alveoli. The NI technique dispersed the particles homogeneously throughout the airways and the alveoli in the lungs. The mean number-percentage and the mean area-percentage data revealed that the doses delivered by ITN and NI were approximately 60% and 10%, respectively, of the ITFI dose. Thus, the ITFI technique appeared to be most suitable for pulmonary absorption and disposition studies where dosage precision is of primary concern. The ITN technique would need further improvement to meet the requirements for dose precision and particle distribution. For both ITFI and ITN, particle size was apparently not a critical determinant for deposition. The NI technique is suitable for inhalation toxicity studies where the pattern and uniformity of particle deposition is the primary concern.