Near-Infrared Spectroscopy (NIRS) for Cerebral and Tissue Oximetry: Analysis of Evolving Applications.

THE USE OF NEAR-INFRARED SPECTROSCOPY (NIRS) has increased significantly worldwide in the past decade. This technology, first described more than 40 years ago, is based on the fact that near-infrared light is able to penetrate biologic tissue and can obtain real-time, noninvasive information on tissue oxygenation and metabolism. In the clinical setting, NIRS has been able to provide clinicians potentially valuable information in patients with impaired microcirculations (systemic and cerebral). Near-infrared spectroscopy has progressed beyond assessment of brain oxygenation to monitor local tissue and muscle oxygenation and perfusion. This review analyzes the published data and provides the clinician a comprehensive account of the perioperative utility of NIRS in cardiac, vascular and thoracic surgery, as well as its increasing role in tissue/muscle oxygenation monitoring.

An algorithm for differentiating food antigen-related gastrointestinal symptoms.

AIM: The aim of this clinical audit was to assess patient-reported outcomes on the effect of dietary intervention, to enhance our understanding of possible treatment options in irritable bowel syndrome (IBS). BACKGROUND: A large number of food-related gastro-intestinal disorders have been attributed to IBS for decades. METHODS: Patient-reported outcomes from the records of 149 IBS patients treated at secondary and tertiary Gastroenterology outpatients in two UK hospitals between January 2014 and July 2016 were audited. Patients all presented with symptoms fulfilling Rome III-IV criteria for IBS had negative coeliac serology and did not have other gastrointestinal (GI) conditions. A modified version of a low FODMAP diet had been recommended (gluten and lactose free diet (G/LFD)) and was implemented for 6 weeks. Outcomes and dietary adherence were recorded during outpatient's consultations. RESULTS: A total of 134 patients complied with the diet optimally. The majority had an improvement rate >70% and continued with the diet. Fifty-three percent became completely or almost asymptomatic, while 27.6% had a poor response to the diet (scoring < 30%) to G/LFD. The improvement was excellent in patients with normal BMI and good in overweight and obese and where BMI <18. Over 50% did not require any follow-up within 12 months. CONCLUSION: Although it is unclear whether symptoms are triggered by gluten, fructans or lactose, elimination of gluten and lactose proved to be an effective treatment in patients with IBS. Multidisciplinary team management and implementation of detailed nutrition therapy using the audit algorithm might prove to be both cost effective and efficacious a treatment option in IBS.

Secondary Tumors of the Ampulla of Vater: A Tale of Two Cases.

We report two cases of women with metastatic cancers to ampulla of Vater. The first was 91 years old and presented with severe anemia, due to upper gastrointestinal bleeding. She had history of renal cell cancer treated with nephrectomy 8 years ago and diagnosis confirmed to be metastasis of renal cell cancer to ampulla of Vater. The second patient was 54 years old with breast cancer, metastasis and developed obstructive jaundice; diagnosis confirmed to be breast metastasis in the ampulla of Vater. Secondary tumors of the ampulla of Vater due to breast cancer and renal cell cancer are rare findings and prognosis can be poor.

The correlation between vitamin D levels and demographics in patients with gastrointestinal disorders; a cross-sectional study.

AIM: The aim of the present study was to evaluate vitamin D levels, in correlation with age, body mass index (BMI), gender and ethnicity, in patients with gastrointestinal disorders (GID). BACKGROUND: Vitamin D deficiency (VDD) is a global health issue, affecting over 1 billion people. A great body of evidence has shown that it can lead to increased morbidity and mortality. Furthermore, latitude, sedentary lifestyle, limited sunlight exposure, ageing and the presence of comorbidities and chronic illnesses, places patients at an increased risk of VDD. METHODS: 305 consecutive patients, with GID, were assessed for vitamin D levels, using a two-step competitive binding immunoenzymatic assay. Patients were then classified as adequate (50-150nmol/l), insufficient (25-50nmol/l) and deficient (<25nmol/l). RESULTS: 62% of the investigated subjects had low vitamin D levels. From this group, 132 patients (43.3%) had insufficient vitamin D levels, 57 (18.7%) had deficient levels and 116 (38%) had adequate levels. Age was not significantly different in the 3 groups (p=0.29). Interestingly, vitamin D levels were significantly lower in men (39.23±23.62) compared to women (50.68±24.46) (p=0.0001). The BMI was significantly higher in patients with insufficient vitamin D levels. Being of Asian ethnicity had a positive influence on vitamin D levels (B=0.076) (p<0.0001). 71.4% of patients, with IBD, and 60% of patients, with abnormal liver function, had low vitamin D levels. CONCLUSION: VDD has a high prevalence in patients with GID in particular IBD and liver disease in the United Kingdom. Routine vitamin D testing and supplementations in the case of deficiency and suboptimal level of vitamin D for patients with hepatobiliary, pancreatic, kidney, malabsorptive and restrictive diseases/surgeries is recommended.

PID Fuzzy Control Applied to an Electrosurgical Unit for Power Regulation.

The electrosurgical unit (ESU) is the most common device in modern surgery for cutting and coagulation of tissues. It produces high-frequency alternating current to prevent the stimulation of muscles and nerves. The commercial ESUs are generally expensive and their output power is uncontrolled. The main objective of the proposed study is to propose an economic ESU with an additional feature of output power regulation using a fuzzy logic controller (FLC) based proportional integral derivative (PID) tuned controller. Unlike the previous studies, the proposed controller is designed in a fully closed-loop control fashion to regulate the output power of the ESU to a fixed value under the consideration of highly dynamic tissue impedance. The performance of the proposed method is tested in the MATLAB/SIMULINK environment. In order to validate the superiority of the proposed method, a comparative analysis with a simple (PID) controller based ESU is presented.

Environmental impact and pollution-related challenges of renewable wind energy paradigm - A review.

With ever increasing environmental and socio-economic awareness, government and legislative authorities, around the globe, are concerned and considering the pollution-related challenges and parameters that influence the energy paradigm. Therefore, renewable energy resources, for instance, wind, solar, and hydro- are used to generate electricity to reduce fossil-fuel-related environmental concerns. The world needs swift, equitable, significant, and effective climate action on this stage. The scientific evidence has been mounting for decades to employ renewable energy resources. One of these shared resources is wind energy, which currently appears as an emerging source of energy around the world. Electricity production using wind power schemes could be an essential replacement for conventional fossil-based fuel resources by using different modalities. Although the initial cost of installing a photovoltaic system is relatively high, however, the running cost is very low. Herein, we reviewed the environmental impact and considerable challenges of the technological paradigm for the development of wind energy technology with particular reference to Pakistan's future perspective. It is anticipated that the discussion provided can stimulate a negotiation between decision makers and raise attentiveness of environmental characteristics and a set of challenges related to the wind power industry development of Pakistan.

A Thoracotomy Approach for the Surgical Repair of a Left Ventricular Free Wall Rupture.

In the current era of rapid culprit vessel revascularization in acute myocardial infarction, ventricular free wall rupture is becoming increasingly uncommon. In rare cases adherent pericardium may contain this rupture, creating a temporary stable pseudoaneurysm. With the aid of intraoperative pictures, we describe herein a left thoracotomy approach for the surgical correction of a left ventricular pseudoaneurysm secondary to free wall rupture.

Risk factors, management and outcome of subtypes of ischemic stroke: a stroke registry from the Arabian Gulf.

BACKGROUND: Data on the determinants and outcome of ischemic stroke (IS) from the Arabian Gulf countries (AGC) are still scanty. The aim of this study was to characterize IS in six large stroke centers on the Arabian peninsula. METHODS: IS subtypes were evaluated in four AGC from January 2006 to December 2007 in a large prospective multicenter hospital-based stroke registry including demographics, baseline risk factors, outcome and management. RESULTS: A total of 780 patients with IS were included. Mean age was 58.9 years (63.7% males). Large-artery atherosclerosis (LAA) (38.1%) was the most common subtype followed by lacunar stroke (LS)(34.7%), cardioembolic stroke (CE)(13.5%) and other determined causes (7%). LAA and CE were both more commonly observed over the age of 70. LAA showed a higher male preponderance, and the highest prevalence of hypertension, diabetes, obesity and ischemic heart disease among all subtypes. Obesity was a risk factor for both LAA and CE. Anterior circulation stroke was significantly more affected in LAA (21.2%), CE (19%) and LS (15.1%) subtype of stroke than in posterior circulation strokes (4.4%, 2.9% and 2.8%, respectively) (p<0.05). Only 0.8% of patients received thrombolysis. The 90-day outcome was worst in LAA and least affected in LS. The over-all 90-day mortality was 2.1%. CONCLUSIONS: Demographically, our data are different from those in Western registries but the distribution of stroke subtypes is comparable. Compared to Asian registries the ratio LS versus LAA was much lower. For the first time these data allow to study the IS profile in this population.

Fractional doses of inactivated poliovirus vaccine in Oman.

BACKGROUND: We conducted a clinical trial of fractional doses of inactivated poliovirus vaccine administered to infants in Oman, in order to evaluate strategies for making the vaccine affordable for use in developing countries. METHODS: We compared fractional doses of inactivated poliovirus vaccine (0.1 ml, representing one fifth of a full dose) given intradermally with the use of a needle-free jet injector device, with full doses of vaccine given intramuscularly, with respect to immunogenicity and reactogenicity. Infants were randomly assigned at birth to receive either a fractional dose or a full dose of inactivated poliovirus vaccine at 2, 4, and 6 months. We also administered a challenge dose of monovalent type 1 oral poliovirus vaccine at 7 months and collected stool samples before and 7 days after administration of the challenge dose. RESULTS: A total of 400 infants were randomized, of whom 373 (93.2%) fulfilled the study requirements. No significant baseline differences between the groups were detected. Thirty days after completion of the three-dose schedule, the rates of seroconversion to types 1, 2, and 3 poliovirus were 97.3%, 95.7%, and 97.9%, respectively, in the fractional-dose group, as compared with 100% seroconversion to all serotypes in the full-dose group (P=0.01 for the comparison with respect to type 2 poliovirus; results with respect to types 1 and 3 poliovirus were not significant). The median titers were significantly lower in the fractional-dose group than in the full-dose group (P<0.001 for all three poliovirus serotypes). At 7 months, 74.8% of the infants in the fractional-dose group and 63.1% of those in full-dose group excreted type 1 poliovirus (P=0.03). Between birth and 7 months, 42 hospitalizations were reported, all related to infectious causes, anemia, or falls, with no significant difference between vaccination groups. CONCLUSIONS: These data show that fractional doses of inactivated poliovirus vaccine administered intradermally at 2, 4, and 6 months, as compared with full doses of inactivated poliovirus vaccine given intramuscularly on the same schedule, induce similar levels of seroconversion but significantly lower titers. (Current Controlled Trials number, ISRCTN17418767.)