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A retrospective observational study on the types of anaesthesia in hip fracture surgery

Nawi SNM, Wong B, Edwards S, Loh X, Maddison J

J Perioper Pract, 2023;33(1-2):15-23.
PMID: 34197241 DOI: 10.1177/17504589211006020

BACKGROUND: There is no specific recommendation regarding the type of anaesthesia in hip fracture surgery.
OBJECTIVES: This study sought to examine the current local anaesthetic practice (general anaesthesia versus regional anaesthesia (RA)) in hip fracture surgery and to analyse their associations with perioperative outcomes.
METHODOLOGY: A retrospective observational study of hip fracture patients from April to December 2017 was undertaken. Patient characteristics and perioperative outcomes were analysed against the types of anaesthesia using multiple logistic regression.
RESULTS: One hundred and twelve out of 154 patients (72.7%) had a general anaesthesia. Patients from residential care facilities were more likely to receive general anaesthesia (OR = 2.9, 95% CI: 1.1, 7.4; P = 0.03). There was no significant association between type of anaesthesia and specific postoperative outcomes; however, patients with postoperative delirium and hypotension were more likely to have received general anaesthesia [OR = 1.7, 95% CI: 0.68, 4.38; P = 0.25] and [OR = 1.6, 95% CI: 0.67, 4.04; P = 0.27] respectively). Subgroup analysis showed increased length of stay with patients who underwent general anaesthesia (OR = 1.26, 95% CI:1.04, 1.54; P = 0.02).
CONCLUSION: Regional anaesthesia may be considered in patients without contraindications in view of increased risk of postoperative delirium and hypotension, and longer length of stay with general anaesthesia. A larger prospective study is needed to confirm these findings.
The potential of decorative building materials (marble) for retrospective thermoluminescence dosimetry

Yasmin S, Khandaker MU, Nawi SNM, Sani SFA, Bradley DA, Islam MA

Appl Radiat Isot, 2021 Sep;175:109782.
PMID: 34082304 DOI: 10.1016/j.apradiso.2021.109782

Among the various types of decorative materials used in Bangladeshi dwellings, the marble/marble stone is one of the most common ones that used largely for enhancing the beauty and/or aristocracy of the dwelling environment. In this study, the most commonly used, six types of marble stones, have been analyzed for retrospective accident dosimetry. With the interest of characterizing several key thermoluminescence properties to examine their potentiality for dosimetry, annealing - irradiation - readout steps have been done chronologically which comprises the analysis of glow curves, relative sensitivity, dose dependence, repeatability and fading. Considering the various TL parameters, marble 'Carrara' imported from Italy present relatively better capability for reconstruction of radiation dose in the dose range of 10-50 Gy. From fading result, it is clear that for reconstruction of absorbed dose up to four weeks of post exposure, the marble 'Carrara' is found to be the most reliable media among the studied marble types. The Zeff values for the various marble samples are found to be in the range of 13.65-19.12, comparing favorably in replace of TLD-200 (Zeff = 16.3) which can be used for low-level environmental radiation dosimetry. Present work constitutes the first study to investigate the potentials of marble stone for reconstruction of absorbed dose in the range of 10-50 Gy dose.
Sub kGy photon irradiation alterations in graphite

Bradley DA, Nawi SNM, Khandaker MU, Almugren KS, Sani SFA

Appl Radiat Isot, 2020 Jul;161:109168.
PMID: 32321700 DOI: 10.1016/j.apradiso.2020.109168

Present work concerns polymer pencil-lead graphite (PPLG) and the potential use of these in elucidating irradiation-driven structural alterations. The study provides detailed analysis of radiation-induced structural interaction changes and the associated luminescence that originates from the energy absorption. Thermally stimulated emission from the different occupied defect energy levels reflects the received radiation dose, different for the different diameter PPLGs. The PPLG samples have been exposed to photon irradiation, specifically x-ray doses ranging from 1 to 10 Gy, extended to 30-200 Gy through use of a60Co gamma-ray source. Trapping parameters such as order of kinetics, activation energy and frequency factor are estimated using Chen's peak-shape method for a fixed-dose of 30 Gy. X-ray diffractometry was used to characterize the crystal structure of the PPLG, the aim being to identify the degree of structural order, atomic spacing and lattice constants of the various irradiated PPLG samples. The mean atomic spacing and degree of structural order for the different diameter PPLG are found to be 0.3332 nm and 26.6° respectively. Photoluminescence spectra from PPLG arising from diode laser excitation at 532 nm consist of two adjacent peaks, 602 nm (absorption) and 1074 nm (emission), with mean energy band gap values within the range 1.113-1.133 eV.
Physicians' perceived barriers and enablers for deprescribing among older patients at public primary care clinics: a qualitative study

Tangiisuran B, Rajendran V, Sha'aban A, Daud NAA, Nawi SNM

Int J Clin Pharm, 2021 Oct 12.
PMID: 34642869 DOI: 10.1007/s11096-021-01336-w

Background Increased harmful effects of medication resulting from polypharmacy, especially among older patients, is a significant concern globally. Hence, continuous medication review and withdrawal of inappropriate medications are essential to improve patient safety. Objective To explore physicians' perceived barriers and enablers of deprescribing among older patients in the public primary healthcare setting. Setting Public primary care clinics in the northern states of Malaysia. Methods A semi-structured, face-to-face interview was conducted among physicians working in eight primary care clinics in northern Malaysia using a purposive sampling approach. Interviews were conducted using validated topic guides. All the responses were recorded, transcribed verbatim, validated, and analysed for the emerging themes using thematic analysis. Main outcome measure Physicians perceived barriers and enablers of deprescribing among geriatric patients. Results A total of eleven physicians were interviewed. Seven emerging themes were identified, which are categorised under barriers and enablers of deprescribing. The barriers were patient-specific, prescriber-specific, and healthcare provision and system. Prescriber deprescribing competencies, medication-specific outcomes, availability of empirical evidence, and pharmacist's role were the enablers identified. Conclusion Patient-specific barriers were identified as a significant challenge for deprescribing. Improving competencies on deprescribing was the repeatedly adduced enabler by physicians. The development of targeted educational training can help to reduce the obstacles faced by prescribers.
Thermoluminescent characterization and defect studies of graphite-rich media under high dose neutron exposure

Khandaker MU, Nawi SNM, Lam SE, Sani SFA, Islam MA, Islam MA, et al.

Appl Radiat Isot, 2023 Jun;196:110771.
PMID: 36933313 DOI: 10.1016/j.apradiso.2023.110771

Thermoluminescence (TL) materials have a broad variety of uses in various fields, such as clinical research, individual dosimetry, and environmental dosimetry, amongst others. However, the use of individual neutron dosimetry has been developing more aggressively lately. In this regard, present study establishes a relationship between the neutron dosage and the optical property changes of graphite-rich materials caused by high doses of neutron radiation. This has been done with the intention of developing a novel, graphite-based radiation dosimeter. Herein, the TL yield of commercially graphite-rich materials (i.e. graphite sheet, 2B and HB grade pencils) irradiated by neutron radiation with doses ranging from 250 Gy to 1500 Gy has been investigated. The samples were bombarded with thermal neutrons as well as a negligible amount of gamma rays, from the nuclear reactor TRIGA-II installed at the Bangladesh Atomic Energy Commission. The shape of the glow curves was observed to be independent of the given dosage, with the predominant TL dosimetric peak maintained within the region of 163 °C-168 °C for each sample. By studying the glow curves of the irradiated samples, some of the most well theoretical models and techniques were used to compute the kinetic parameters such as the order of kinetics (b), activation energy (E) or trap depth, frequency factor (s) or escape probability, and trap lifetime (τ). All of the samples were found to have a good linear response over the whole dosage range, with 2B grade of polymer pencil lead graphite (PPLGs) demonstrating a higher level of sensitivity than both HB grade and graphite sheet (GS) samples. Additionally, the level of sensitivity shown by each of them is highest at the lowest dosage that was given, and it decreases as the dose increases. Importantly, the phenomenon of dose-dependent structural modifications and internal annealing of defects has been observed by assessing the area of deconvoluted micro-Raman spectra of graphite-rich materials in high-frequency areas. This trend is consistent with the cyclical pattern reported in the intensity ratio of defect and graphite modes in previously investigated carbon-rich media. Such recurrent occurrences suggest the idea of employing Raman microspectroscopy as a radiation damage study tool for carbonaceous materials. The excellent responses of the key TL properties of the 2B grade pencil demonstrate its usefulness as a passive radiation dosimeter. As a consequence, the findings suggest that graphite-rich materials have the potential to be useful as a low-cost passive radiation dosimeter, with applications in radiotherapy and manufacturing.