32 research outputs found
Prognostic utility of monocyte distribution width in critically ill patients
Background
Sepsis is one of the leading causes of intensive care unit (ICU) admission and mortal- ity in Malaysia. Delayed recognition of sepsis is associated with increased morbidity and mortality. Monocyte distribution width (MDW) represents the width of a set of monocyte volume values, which increases as infection progress in severity. Its mea- surement is one of the haematologic parameter of complete blood count, hence, it does not incur added cost and is widely available. We evaluated the prognostic ac- curacy of MDW.
Methods
This was a prospective cohort study of 100 patients who are grouped into sepsis and non-sepsis according to the Sepsis-3 definition. This study enrolled adults, age 18 years and above, whose evaluation included a complete blood count with differ- ential upon admission to ICU. Exclusion criteria included patient refusal to join the study, readmission to ICU within 12 hours and prior study enrolment. MDW and WBC were collected on admission to ICU and for subsequent 3 days. The study had ob- tained approval from the IIUM Research Ethics Committee (Number 2020-079).
Results
A total of 100 patients were recruited in the study. Twenty-three patients (23%) died within 30 days of ICU admission. MDW were predictive of 30-day mortality with a cut-off point of 25.97. Patients with on admission MDW higher than this cut-off point were more likely to die with 30 days compared to those with lower value. WBC on admission and throughout 3 days were not predictive of 30-day mortality.
Conclusion
MDW is an effective prognosis tool of mortality upon admission to ICU. As part of the differential in CBC, MDW makes a cost effective and widely available test at present. Early prediction of death allows for risk stratification for patients admitted to the ICU
Performance of STAR virtual trials for diabetic and non-diabetic in HTAA Intensive Care Unit
Critically ill patients are commonly linked to stress-induced hyperglycaemia which relates to insulin resistance and the risk of per-diagnosed with diabetes and other metabolic illnesses. Thus, it is essential to choose the best practice of blood glucose management in order to reduce morbidity and mortality rates in intensive care unit. This study is focusing on clinical data of 210 critically ill patients in Hospital Tengku Ampuan Afzan (HTAA), Kuantan who underwent Intensive Insulin Therapy which utilized a sliding scale method. Patients were identified in two main groups of diabetic (123) and non-diabetic (87) where stochastic model is generated to observe 90% confidence interval of insulin sensitivity. Blood glucose levels comparison between these two cohorts is conducted to observe the percentage of blood glucose levels within targeted band of 4.4 โ 10.0 mmol/L. It is found that 82% of BG levels are within targated band for non-diabetes cohort under stochastic targeted (STAR) glycaemic control protocol. However, only 59.6% and 70.6% BG levels are within targeted band for diabetes cohort for insulin infusion therapy used in HTAA and STAR protocols. Thus, further investigation on blood glucose control protocol for diabetes patients is required to increase the reliability and efficacy of current practice despite of patient safety
A study on controllable aluminium doped zinc oxide patterning by chemical etching for MEMS application
This present work reports on the study of controllable aluminium doped zinc oxide (AZO) patterning by chemical etching for MEMS application. The AZO thin film was prepared by RF magnetron sputtering as it is capable of producing uniform thin film at high deposition rates. X-Ray diffraction (XRD) and atomic force microscopy (AFM) characterization were done to characterize AZO thin film. The sputtered AZO thin film shows c-axis (002) orientation, low surface roughness and high crystalline quality. To pattern AZO thin film for MEMS application, wet etching was chosen due to its ease of processing with few controlling parameters. Four etching solutions were used namely: 10 % Nitric acid, 10 % Phosphoric acid, 10 % Acetic acid and Molybdenum etch solutions. For the first time, chemical etching using Molybdenum etch that consist of a mixture of CH3COOH, HNO3 and H3PO4 was characterized and reported. The effect of these acidic solutions on the undercut etching, vertical and lateral etch rate were studied. The etched AZO were characterized by scanning electron microscopy (SEM) and stylus profilometer. The investigations showed that the Molybdenum etch has the lowest undercut etching of 7.11 ยตm, and is highly effective in terms of lateral and vertical etching with an etch ratio of 1.30. Successful fine patterning of AZO thin films was demonstrated at device level on a surface acoustic wave resonator fabricated in 0.35 ฮผm CMOS technology. The AZO thin film acts as the piezoelectric thin film for acoustic wave generation. Patterning of the AZO thin film is necessary for access to measurement probe pads. The working acoustic resonator showed resonance peak at 1.044 GHz at 45.28 dB insertion loss indicating that the proposed Molybdenum etch method does not adversely affect the deviceโs operating characteristic
Predictive models for kidney disease: improving global outcomes (KDIGO) defined acute kidney injury in UK cardiac surgery
Performance of Glycemic Control Protocol and Virtual Trial
Model-based glycemic control offers direct management of patient-specific variability and better adaptive control. Implementation of the model-based glycemic control has the potential to reduce hyperglycemia episodes, mortality and morbidity as seen in some successful TGC. The design of any TGC must consider not only the glycemic target range but also safety and efficacy of the insulin therapy. This paper presents the evaluation of glycemic control protocol adapted in the ICU of Tengku Ampuan Afzan Hospital. Virtual trials method is used to simulate the controller algorithm on a virtual patient with feed variation factor. Data from actual clinical and the virtual trial are compared to analyze the protocol performance concerning blood glucose outcome and insulin efficacy. A stochastic model is also used to indicate metabolic response and metabolic variation of the cohort
A PWM controller of a full bridge single-phase synchronous inverter for micro-grid system
Nowadays, microgrid system technology is becoming popular for small area power management systems. It is essential to be less harmonic-distortion and high efficiency of the inverter for microgrid applications. Pulse width modulation (PWM) controller is a conventional switching control technique which is suitable to use in the microgrid connected power inverter system. The control method and algorithm of this technique are challenging, and different approaches are required to avoid the complexity for a customized solution of the microgrid application. This paper proposes a comparative analysis of different controller and their operational methods. A PWM controller is used to reduce the ripple voltage noise while a continuous current mode provides a small output ripple which gives steady-state error as zero on fundamental and cutoff frequency. To reduce the ripple current, higher frequency harmonic distortion, switching loss and phase noise, LC low pass filter is used on either side of input and output terminals. The proposed inverter is designed by MATLAB 2016a simulation software. A balanced load resistance (RL = 20.5 ฮฉ) of star configuration and a dual input DC voltage of ยฑ 35V are considered. In this design, the circuit parameters, the fundamental frequency of 50 Hz, the PWM duty cycle of 95%, the cutoff frequency of the switching controller of 33 kHz are considered. The inverter in this paper exhibits THD of 0.44% and overall efficiency approximately of 98%. The proposed inverter is expected to be suitable for microgrid applications
Piezoelectric thin films for double electrode CMOS MEMS surface acoustic wave (SAW) resonator
CMOS integration for RF-MEMS is desired
to yield compact, low-power and portable devices. In this
work, we illustrate the usage of double electrode CMOS
SAW resonators using both ZnO and AlN as its piezoelectric
material. Double electrode transducers were chosen,
as they are better at suppressing undesired acoustic reflections
compared to single electrodes. The structure and
dimension of the device is based on 0.35 ฮผm CMOS process
where the IDTs are fabricated using standard CMOS
fabrication process. 2D Finite element modeling of the
CMOS SAW resonator using COMSOL Multiphysicsยฎ is
presented. Two-step eigenfrequency and frequency domain
analyses were performed. The acoustic velocities generated
are 3,925 and 5,953 m/s for ZnO and AlN CMOS
SAW resonator respectively. Higher acoustic displacement
and surface potential were observed in ZnO compared to
AlN. It can be concluded that ZnO thin films have higher electromechanical coupling coefficients and are more efficient than AlN thin films
Probabilistic glycemic control decision support in ICU : proof of concept using bayesian network
Glycemic control in intensive care patients is complex in terms of patientsโ response to care and treatment. The variability and the search for improved insulin therapy outcomes have led to the use of human physiology model based on per-patient metabolic condition to provide personalized automated recommendations. One of the most promising solutions for this is the STAR protocol, which is based on a clinically validated insulin-nutrition-glucose physiological model. However, this approach does not consider demographical background such as age, weight, height, and ethnicity. This article presents the extension to intensive care personalized solution by integrating per-patient demographical, and upon admission information to intensive care conditions to automate decision support for clinical staff. In this context, a virtual study was conducted on 210 retrospectives intensive care patientsโ data. To provide a ground, the integration concept is presented roughly, but the details are given in terms of a proof of concept using Bayesian Network, linking the admission background and performance of the STAR control. The proof of concept shows 71.43% and 73.90% overall inference precision, and reliability, respectively, on the test dataset. With more data, improved Bayesian Network is believed to be reproduced. These results, nevertheless, points at the feasibility of the network to act as an effective classifier using intensive care units data, and glycemic control performance to be the basis of a probabilistic, personalized, and automated decision support in the intensive care unit
Acute high-dose intravenous epoetin did not increase blood pressure in critically ill patients with acute kidney injury
Introduction: Erythropoiesis stimulating agents (ESA) correction of renal anemia increases blood pressure in as many as 35% of patients. It is uncertain whether this phenomenon is due to ESA-induced vasoconstriction and/or increased red blood cell mass. The Early Intervention in Acute Renal Failure (EARLYARF) trial4 provided an opportunity to assess whether intravenous (IV) epoetin induces immediate vasoconstriction.
Method: A post-hoc analysis of 160 of 163 patients randomized to receive two doses 24 hours apart of IV epoetin (500 U/kg) or placebo. These intensive-care patients were enrolled following identification of acute kidney injury (AKI) by the urinary biomarkers ฮณ-glutamyltranspeptidase and alkaline phosphatase. Hourly mean arterial pressures (MAP), and norepinephrine equivalent dose (NED: determined using equipotency conversion factors for doses of epinephrine, vasopressin, phenylephrine, or dopamine), and hemoglobin (Hb) and hematocrit (Hct) were extracted from clinical records. The differences between maximum and baseline MAP and NED (ฮMAP and ฮNED) were determined at 4, 24, and 72 hours, and Hb and Hct at 7, and 30-day after study drug administration.
Result: At baseline, MAP was 78ยฑ14 mmHg in the epoetin group and 81ยฑ15 mmHg in the placebo group (p=0.22). There were no differences between groups in ฮMAP, ฮNED or ฮMAP adjusted for ฮNED at 4-h after the first and second drug dose (Table 1). Similarly, there were no differences within 24 hours (Figure 1), or at any other time points. Hemoglobin concentration and hematocrit were unchanged. A subgroup analysis of patients with no vasopressor use (n=71) also showed no differences between epoetin and placebo for all outcomes.
Conclusion: Parenteral high dose epoetin administration did not acutely increase blood pressure in critically ill individuals at risk of acute kidney injury, suggesting epoetin did not induce acute vasoconstriction
Estimation of plasma insulin and endogenous insulin secretion in critically ill patients using ICING model
The objective of this study is to estimate total plasma insulin level and endogenous insulin secretion by using Intensive Control Insulin-Nutrition-Glucose (ICING) model and 90 critically ill patientsโ data from Hospital Tengku Ampuan Afzan, Kuantan. Integral-based method was applied to solve mathematical equations defined in ICING model to find critical parameters of insulin sensitivity (SI) and results of total endogenous insulin secretion and total plasma insulin level were presented in median and 95% confidence interval (CI). It is reported that the total median plasma insulin is 1.35 x 106 mU while (6.59 x 105, 2.79 x 106) mU is in 95% CI, and the total median endogenous insulin secretion is 12.9% from the total median plasma insulin. The results elucidated the effectiveness of current practice via Intensive Insulin Infusion Therapy (IIT) and also suggest a further study on investigating the incretin mechanism which is strongly believed to contribute to the total plasma insulin level and help to simulate endogenous insulin secretio