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1.
J Surg Res ; 302: 891-896, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39265276

RESUMO

INTRODUCTION: The measure of mortality following a major complication (failure to rescue [FTR]) provides a quantifiable assessment of the level of care provided by trauma centers. However, there is a lack of data on the effects of patient-related factors on FTR incidence. The aim of this study was to identify the role of frailty on FTR incidence among geriatric trauma patients with ground-level falls (GLFs). METHODS: This is a retrospective analysis of the American College of Surgeons Trauma Quality Improvement Program database (2017-2020). All geriatric (aged ≥ 65 ys) trauma patients with GLFs admitted to a level I trauma center were included. Transferred patients, those with severe head injuries (head abbreviated injury scale ≥ 3), and those who died within 24 h of admission or whose length of stay was ≤1 d were excluded. FTR was defined as death following a major complication (cardiac arrest, myocardial infarction, sepsis, acute respiratory distress syndrome, unplanned intubation, acute renal failure, cerebrovascular accident, ventilator-associated pneumonia, or pulmonary embolism). Patients were stratified into frail (F) and nonfrail (NF) based on the 11-Factor Modified Frailty Index. Multivariable regression analyses were performed to identify the independent effect of frailty on the incidence of FTR. RESULTS: Over 4 ys, 34,100 geriatric patients with GLFs were identified, of whom 9140 (26.8%) were F. The mean (standard deviation) age was 78 (7) years and 65% were female. The median injury severity score was 9 (5-10) with no difference among F and NF groups (P = 0.266). Overall, F patients were more likely to develop major complications (F: 3.6% versus NF: 2%, P < 0.001) and experience FTR (F: 1.8%% versus NF: 0.6%, P < 0.001). Moreover, among patients with major complications, F patients were more likely to die (F: 47% versus NF: 27%, P < 0.001). On multivariable regression analysis, frailty was identified as an independent predictor of major complications (adjusted odds ratio: 1.98, 95% confidence interval [1.70-2.29], P < 0.001) and FTR (adjusted odds ratio: 2.26, 95% confidence interval [1.68-3.05], P < 0.001). CONCLUSIONS: Among geriatric trauma patients with GLFs, frailty increases the risk-adjusted odds of FTR by more than two times. One in every two F patients with a major complication does not survive to discharge. Future efforts should concentrate on improving patient-related and hospital-related factors to decrease the risk of FTR among these vulnerable populations.

2.
J Surg Res ; 303: 14-21, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39288515

RESUMO

BACKGROUND: Diagnostic laparoscopy (DL) has been advocated to reduce the incidence of nontherapeutic laparotomies (NL) among stable trauma patients. This study aimed to compare the outcomes of hemodynamically stable trauma patients undergoing DL versus NL. METHODS: This is a retrospective analysis of the American College of Surgeons Trauma Quality Improvement Program database over 4 y (2017-2020). Hemodynamically stable (systolic blood pressure >90 & heart rate < 120) adult (≥18 y) trauma patients undergoing DL or NL were included. Patients were stratified into DL and NL and substratified based on the mechanism of injury (blunt versus penetrating) and compared. RESULTS: Over 4 y, 3801 patients were identified, of which, 997 (26.2%) underwent DL. Overall, 25.6% sustained blunt injuries. The mean (SD) age was 39 (16) and 79.5% were male. The median injury severity score and abdominal abbreviated injury scale were 4 [4-9] and 1 [1-2], with no difference among study groups (P ≥ 0.05). The overall mortality and major complication rates were 2.8% and 13.2%, respectively. After controlling for potential confounding factors, DL was independently associated with lower odds of mortality (adjusted odds ratio: 0.10, 95% CI [0.04-0.29], P < 0.001) and major complications (adjusted odds ratio: 0.38, 95% CI [0.29-0.50], P < 0.001) and shorter hospital length of stay (ß: -1.22, 95% CI [-1.78 to -0.67], P < 0.001). The trends toward improved outcomes in the DL group remained the same in the subanalysis of patients with penetrating and blunt injuries. CONCLUSIONS: With advances in minimally invasive surgery, unnecessary exploratory laparotomy can be avoided in many trauma patients. Our study shows that hemodynamically stable patients undergoing DL had superior outcomes compared to those with NL.

3.
J Surg Res ; 302: 656-661, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39208490

RESUMO

INTRODUCTION: Most traumatic lung injuries are managed non-operatively. There is a paucity of recent data on the outcomes of operatively managed lung injuries. The aim of our study is to determine the survival rates of operatively managed traumatic lung injury patients on a nationwide scale. METHODS: We performed a retrospective analysis of the ACS-TQIP 2017-2020. We included all adult trauma patients with lung injuries that underwent operative management. Patients were stratified based on type of surgery into 3 groups (wedge resection, lobectomy, pneumonectomy). The outcome was mortality. Multivariable logistic regression analysis was performed to identify the independent predictors of mortality. RESULTS: We identified a total of 170,377 patients with lung injuries, out of which 2159 (1.3%) patients underwent operative management (Wedge resection [61%], Lobectomy [31%], Pneumonectomy [8%]). Among operatively managed patients, the mean (SD) age was 37 (16) years, and 86% were male. Overall, 65% sustained penetrating injuries, with a median [IQR] ISS of 25 [16 - 33], and median [IQR] lung injury AIS severity of 4 [3 - 4]. About 7% of the patients suffered hilar injuries. The mean (SD) SBP on arrival was 108 (43) and the median [IQR] time to surgery was 177 [52 - 5351] minutes. The median hospital LOS was 10 [1 - 19] days, and overall mortality rate was 30%. On univariate analysis, patients undergoing pneumonectomy had the highest mortality (54%), followed by lobectomy (33%), and wedge resection (25%). On multivariable regression analysis, hilar injuries (aOR 1.9, 95%CI = 1.06 - 2.80, P = 0.029), increasing age (aOR 1.02, 95%CI = 1.01 - 1.03, P = 0.001), concomitant head (aOR 1.34, 95%CI = 1.22 - 1.47, P < 0.001) and abdominal injuries (aOR 1.42, 95%CI = 1.31 - 1.54, P < 0.001) were independent predictors of mortality. CONCLUSIONS: Nearly 1 in 3 patients with lung injuries who were managed operatively did not survive their index admission. These findings highlight that operatively managed lung injuries still carry a high risk of mortality and should be reserved for selected patients. The decision for surgery in patients with concomitant head or abdominal injuries must be taken on a case-to-case basis.

4.
J Surg Res ; 301: 385-391, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39029261

RESUMO

INTRODUCTION: There is a lack of data on the outcomes of thoracic damage control surgery (TDCS). This study aimed to describe the characteristics and outcomes of patients undergoing TDCS. METHODS: This is a retrospective analysis of the American College of Surgeons-Trauma Quality Improvement Program database (2017-2021). All trauma patients who underwent emergency thoracotomy and packing with temporary closure were included. Patients were stratified based on the age groups (pediatric [<18 y], adults [18-64 y], and older adults [≥65 y]). Our primary outcome measures included 6-h, 24-h, and in-hospital mortality. Secondary outcomes were major complications. RESULTS: We identified 14,192 thoracotomies, out of which 213 underwent TDCS (pediatric [n = 17], adults [n = 175], and older adults [n = 21]). The mean (SD) age was 37 (18), and 86% were male. The mean shock index was 1.1 (0.4) on presentation with a median [IQR] Glasgow Coma Scale of 4 [3-14], and 22.1% had a prehospital cardiac arrest. The study population was profoundly injured with a median injury severity scoreand chest-abbreviated injury scale of 26 [17-38] and 4 [3-5], respectively, with lung (76.5%) being the most injured intrathoracic organs. Overall, the rates of 6-h, 24-h, and in-hospital mortality were 22.5%, 33%, and 53%, respectively, and 51% developed major complications. There was no significant difference in terms of in-hospital mortality (P = 0.800) and major complications (0.416) among pediatrics, adults, and older adults. CONCLUSIONS: One in three patients undergoing TDCS die within the first 24 h, and more than half of them develop major complications and die in the hospital, with no difference among pediatric, adults, and older adults. Future efforts should be directed to improve the survival of these severely injured, metabolically depleted, challenging patients.


Assuntos
Mortalidade Hospitalar , Traumatismos Torácicos , Toracotomia , Humanos , Masculino , Feminino , Estudos Retrospectivos , Adulto , Traumatismos Torácicos/cirurgia , Traumatismos Torácicos/mortalidade , Pessoa de Meia-Idade , Idoso , Adolescente , Adulto Jovem , Toracotomia/mortalidade , Toracotomia/estatística & dados numéricos , Criança , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/mortalidade , Escala de Gravidade do Ferimento , Resultado do Tratamento
5.
J Surg Res ; 301: 591-598, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39094517

RESUMO

INTRODUCTION: This study aimed to develop and validate Futility of Resuscitation Measure (FoRM) for predicting the futility of resuscitation among older adult trauma patients. METHODS: This is a retrospective analysis of the American College of Surgeons-Trauma Quality Improvement Program database (2017-2018) (derivation cohort) and American College of Surgeons level I trauma center database (2017-2022) (validation cohort). We included all severely injured (injury severity score >15) older adult (aged ≥60 y) trauma patients. Patients were stratified into decades of age. Injury characteristics (severe traumatic brain injury [Glasgow Coma Scale ≤ 8], traumatic brain injury midline shift), physiologic parameters (lowest in-hospital systolic blood pressure [≤1 h], prehospital cardiac arrest), and interventions employed (4-h packed red blood cell transfusions, emergency department resuscitative thoracotomy, resuscitative endovascular balloon occlusion of the aorta, emergency laparotomy [≤2 h], early vasopressor requirement [≤6 h], and craniectomy) were identified. Regression coefficient-based weighted scoring system was developed using the Schneeweiss method and subsequently validated using institutional database. RESULTS: A total of 5562 patients in derivation cohort and 873 in validation cohort were identified. Mortality was 31% in the derivation cohort and FoRM had excellent discriminative power to predict mortality (area under the receiver operator characteristic = 0.860; 95% confidence interval [0.847-0.872], P < 0.001). Patients with a FoRM score of >16 had a less than 10% chance of survival, while those with a FoRM score of >20 had a less than 5% chance of survival. In validation cohort, mortality rate was 17% and FoRM had good discriminative power (area under the receiver operator characteristic = 0.76; 95% confidence interval [0.71-0.80], P < 0.001). CONCLUSIONS: FoRM can reliably identify the risk of futile resuscitation among older adult patients admitted to our level I trauma center.


Assuntos
Futilidade Médica , Ressuscitação , Humanos , Estudos Retrospectivos , Idoso , Feminino , Masculino , Ressuscitação/métodos , Ressuscitação/normas , Pessoa de Meia-Idade , Ferimentos e Lesões/terapia , Ferimentos e Lesões/mortalidade , Ferimentos e Lesões/diagnóstico , Idoso de 80 Anos ou mais , Escala de Gravidade do Ferimento , Centros de Traumatologia/estatística & dados numéricos
6.
J Surg Res ; 301: 45-53, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38909477

RESUMO

INTRODUCTION: There is a paucity of data on the effect of preinjury substance (alcohol, drugs) abuse on the risk of delirium in patients with traumatic brain injury (TBI). This study aimed to assess the incidence of delirium among patients with blunt TBI in association with different substances. METHODS: We analyzed the 2020 American College of Surgeons-Trauma Quality Improvement Program. We included all adult (≥18 y) patients with blunt TBI who had a recorded substance (drugs and alcohol) screening. Our primary outcome was the incidence of delirium. RESULTS: A total of 72,901 blunt TBI patients were identified. The mean (standard deviation) age was 56 (20) years and 68.0% were males. The median (interquartile range) injury severity score was 17 (10-25). Among the study population, 23.1% tested positive for drugs (Stimulants: 3.0%; Depressants: 2.9%, hallucinogens: 5.1%, Cannabinoids: 13.4%, TCAs: 0.1%), and 22.8% tested positive for Alcohol. Overall, 1856 (2.5%) experienced delirium. On univariate analysis, patients who developed delirium were more likely to have positive drug screening results. On multivariable regression analyses, positive screen tests for isolated stimulants (adjusted odds ratio [aOR]: 1.340, P = 0.018), tricyclic antidepressants (aOR: 3.107, P = 0.019), and cannabinoids (aOR: 1.326, P ≤ 0.001) were independently associated with higher odds of developing delirium. CONCLUSIONS: Nearly one-fourth of adult patients with blunt TBI had an initial positive substance screening test. Patients with positive results for isolated stimulants, tricyclic antidepressants, and cannabinoids were at a higher risk of developing delirium, whereas this association was not evident with other drugs and alcohol-positive tests. These findings emphasize the need for early drug screening in TBI patients and close monitoring of patients with positive screening tests.


Assuntos
Lesões Encefálicas Traumáticas , Delírio , Transtornos Relacionados ao Uso de Substâncias , Humanos , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/epidemiologia , Masculino , Feminino , Delírio/epidemiologia , Delírio/etiologia , Delírio/diagnóstico , Pessoa de Meia-Idade , Incidência , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/complicações , Adulto , Idoso , Estudos Retrospectivos , Fatores de Risco , Escala de Gravidade do Ferimento
7.
J Surg Res ; 302: 621-627, 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39190972

RESUMO

INTRODUCTION: The management of injuries to the iliac artery presents a challenging clinical scenario due to the impeded anatomical access. Obesity is a common comorbid condition known to affect the outcomes of trauma patients; however, there is a paucity of data on the association of obesity with the treatment and outcomes of iliac artery injuries. The aim of this study was to assess the association between body mass index (BMI) on the management and outcomes of patients with iliac artery injuries. METHODS: This is a retrospective analysis of the American College of Surgeons-Trauma Quality Improvement Program (2017-2020). All adult (aged ≥18 y) trauma patients with iliac artery injuries who underwent open or endovascular repair were included. Patients were divided based on BMI (normal: BMI <25 kg/m2, overweight: BMI ≥25-30 kg/m2, obese: BMI ≥30 kg/m2) and compared. Outcomes included rates of open and endovascular repair, in-hospital mortality, and complications. Multivariable regression analysis was performed for these outcomes. RESULTS: A total of 380 patients were identified who underwent repair (Open: 61%, Endovascular: 39%) for iliac artery injuries. The mean (standard deviation) age was 41 (19) y and 74% were male. There was no difference in the rates of open or endovascular repair among the BMI categories (P = 0.332). The median (interquartile range) injury severity score was 22 (9-29) with no difference among the BMI categories (P = 0.244). On univariate analysis, the rates of mortality and major complications were higher among obese patients compared to overweight and normal BMI groups (P < 0.05) (Table). On multivariable regression analysis, increasing BMI was not a predictor of open or endovascular repair of the iliac arteries; however, increasing BMI was independently associated with higher odds of major complications (adjusted odds ratio [aOR]: 1.09, 95% confidence interval [CI] [1.02-1.16], P = 0.007), acute kidney injury (aOR: 1.13, 95% CI [1.02-1.24], P = 0.015), acute respiratory distress syndrome (aOR: 1.18, 95% CI [1.01-1.38], P = 0.031), and mortality (aOR: 1.30, 95% CI [1.06-1.59], P = 0.009). CONCLUSIONS: Although BMI was not identified as a predictor of the type of repair for iliac artery injuries, increasing BMI was significantly associated with mortality, complications, and acute kidney injury in patients who undergo repair of the iliac arteries. Future research is warranted to identify the optimal management approach for obese patients to improve the outcomes.

8.
J Surg Res ; 302: 393-397, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39153360

RESUMO

INTRODUCTION: Trauma and cancer are the leading causes of death in the US. There is a paucity of data describing the impact of cancer on trauma patients. We aimed to determine the influence of cancer on outcomes of trauma patients. METHODS: In this retrospective analysis of American College of Surgeons-Trauma Quality Improvement Program 2019-2021, we included all adult trauma patients (≥18 y) and excluded patients with severe head injuries and nonmelanomatous skin cancers. Patients were stratified into cancer (C), and no cancer (No-C). Propensity score matching (1:3) was performed. Outcomes were complications and mortality. RESULTS: A matched cohort of 3236 patients (C, 809; No-C, 2427) was analyzed. The mean age was 70 y, 50.5% were males, and the median injury severity score was 8 (4-10). There were no differences in terms of receiving thromboprophylaxis (C 51%: No-C 50%, P = 0.516). Compared to No-C group, the C group had higher rates of deep vein thrombosis (C 1.1% versus No-C 0.3%, P = 0.004), but there was no difference in terms of overall complications. Patients in the C group had higher mortality (C 7.5% versus No-C 2.7%, P < 0.001). CONCLUSIONS: Trauma patients with cancer have nearly 4 times higher odds of deep vein thrombosis and 3 times higher odds of mortality. Developing pathways specific to cancer patients might be necessary to improve the outcomes of trauma patients with cancer.

9.
J Surg Res ; 302: 385-392, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39153359

RESUMO

INTRODUCTION: Management of subclavian artery injuries (SAI) and iliac artery injuries (IAI) in adolescent trauma patients poses a considerable challenge due to their complex anatomical locations. The aim of our study was to determine the association between the injury mechanism and type of repair with the outcomes of patients with traumatic SAI and IAI. METHODS: In this retrospective analysis of the American College of Surgeons Trauma Quality Improvement Program database2017-2020, adolescent (<18 y) patients with SAI and IAI undergoing either endovascular or open repair were included. Patients were stratified by mechanism (blunt versus penetrating) and type of repair (endovascular [E] versus open [O]) and compared. Outcomes measured were mortality and major complications. Multivariable logistic regression analyses were performed. RESULTS: Over 4 y, 170 pediatric patients were identified, of which 73 (43%) sustained an SAI and 97 (57%) had IAI. The mean age was 15 and 79% were male. Overall, 39% were managed endovascularly. Both groups had comparable median injury severity score (E: 23 versus O: 25, P = 0.278). For patients with blunt injury (n = 60), the type of repair was neither associated with major complications (E: 39% versus O: 33%, P = 0.694) nor mortality (E: 2.6% versus O: 4.8%, P = 0.651). For patients with penetrating injuries (n = 110), the endovascular repair had significantly lower morbidity (19% versus 41%, P = 0.034) and mortality (3.7% versus 21%, P = 0.041). On multivariable logistic regression, endovascular repair was identified as the only modifiable risk factor associated with reduced mortality (adjusted odds ratio: 0.201, 95% confidence interval [0.14-0.76], P = 0.038). CONCLUSIONS: Difficult-to-access vascular injuries result in significant morbidity and mortality. Endovascular repair was found to be the only modifiable factor associated with decreased mortality of patients with penetrating injury, whereas the type of repair was not associated with mortality in those with blunt injury.

10.
Langenbecks Arch Surg ; 409(1): 269, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39225912

RESUMO

PURPOSE: Robotic-assisted rectal surgery (RARS) and Laparoscopic-assisted rectal surgery are the two techniques that are increasingly used for rectal cancer, and both have their advantages and disadvantages. This meta-analysis will analyze the outcomes of both techniques to determine their relative performance and suitability. METHODS: An extensive search was carried out on PubMed, Cochrane, Scopus, Embase, and Google Scholar, followed by a meta-analysis of all randomized controlled trials (RCTs) to assess both approaches for rectal cancer. RESULTS: This meta-analysis is comprised of fifteen RCTs. The conversion to open surgery (RR = 0.53, 95% CI: 0.38-0.74, P = 0.0002) was significantly lower in the RARS group. The outcomes like anastomotic leak, postoperative ileus, postoperative urinary retention (POUR), surgical site infection (SSI), and intra-abdominal abscess showed no significant difference between the two groups. The reoperation rate (RR = 0.56, 95% CI: 0.34-0.95, P = 0.03) was lower in the robotic group. High heterogeneity was obtained when pooling data on operative time, length of hospital stay, and blood loss. Oncological outcomes, including local recurrence, the number of harvested lymph nodes (LN) and distal resection margin showed no significant distinction among both groups, while the positive circumferential resection margin (CRM) (RR = 0.67, 95% CI: 0.49-0.91, P = 0.01) was lower in the RARS group. RARS demonstrated a significantly higher rate of total mesorectal excision (TME) (RR = 1.07, 95% CI: 1.01-1.14, P = 0.03). CONCLUSION: RARS is safe and feasible for rectal cancer patients and may be superior or equivalent to Laparoscopic-assisted rectal surgery, but high-standard, large-scale trials are required to determine the best approach.


Assuntos
Laparoscopia , Neoplasias Retais , Procedimentos Cirúrgicos Robóticos , Humanos , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Laparoscopia/estatística & dados numéricos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Neoplasias Retais/cirurgia , Neoplasias Retais/patologia , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Procedimentos Cirúrgicos Robóticos/estatística & dados numéricos , Resultado do Tratamento
11.
Sensors (Basel) ; 24(2)2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38257527

RESUMO

Switched filter banks find widespread application in frequency-hopping radar systems and communication networks with multiple operating frequencies, especially in situations demanding elevated filter element isolation. In this paper, the design and implementation of a highly isolated switchable narrow-bandpass filter bank architecture using hairpin microstrip topology is presented. The filter bank has four discrete bandpass filters with passbands of 2.0-2.2 GHz, 2.3-2.5 GHz, 3.1-3.3 GHz, and 3.9-4.1 GHz. These filters span the radar S-frequency band (2.0-4.0 GHz). In order to switch between channels with a switching speed of nanoseconds, low-loss and highly isolated SP4T switches are implemented. Advanced design system (ADS) software is used to design the various filter functionalities, and the entire system is tested on a vector network analyzer (VNA). The proposed architecture makes it much easier to put the filter bank into practice and switch it to the desired frequency, which is useful for radar receiver applications.

12.
Purinergic Signal ; 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37981630

RESUMO

Inflammatory pain, sustained by a complex network of inflammatory mediators, is a severe and persistent illness affecting many of the general population. We explore possible anti-inflammatory pathways of Polyphyllin VI (PPVI) based on our prior study, which showed that PPVI reduces inflammation in mice to reduce pain. Network pharmacology and RNA-Seq identified the contribution of the MAPK signaling pathway to inflammatory pain. In the LPS/ATP-induced RAW264.7 cell model, pretreatment with PPVI for 1 h inhibited the release of IL-6 and IL-8, down-regulated expression of the P2X7 receptor(P2X7R), and decreased phosphorylation of p38 and ERK1/2 components of the MAPK pathway. Moreover, PPVI decreased expression of IL-6 and IL-8 was observed in the serum of the inflammatory pain mice model and reduced phosphorylation of p38 and ERK1/2 in the dorsal root ganglia while the reductions of expression of IL-6 and phosphorylation of ERK1/2 were not observed after the pre-treatment with A740003 (an antagonist of the P2X7R). These results suggest that PPVI may inhibit the release of IL-8 by regulating P2X7R to reduce the phosphorylation of p38. However, the modulation of PPVI on the release of IL-6 and phosphorylation of ERK1/2 may mediated by other P2X7R-independent signals.

13.
Inorg Chem ; 62(23): 8892-8902, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37236171

RESUMO

Two-dimensional hybrid-organic-inorganic perovskite (2D-HOIP) lead bromide perovskite crystals have demonstrated great potential as scintillators with high light yields and fast decay times while also being low cost with solution-processable materials for wide energy radiation detection. Ion doping has been also shown to be a very promising avenue for improvements of the scintillation properties of 2D-HOIP crystals. In this paper, we discuss the effect of rubidium (Rb) doping on two previously reported 2D-HOIP single crystals, BA2PbBr4 and PEA2PbBr4. We observe that doping the perovskite crystals with Rb ions leads to an expansion of the crystal lattices of the materials, which also leads to narrowing of band gaps down to 84% of the pure compounds. Rb doping of BA2PbBr4 and PEA2PbBr4 shows a broadening in the photoluminescence and scintillation emissions of both perovskite crystals. Rb doping also leads to faster γ-ray scintillation decay times, as fast as 4.4 ns, with average decay time decreases of 15% and 8% for Rb-doped BA2PbBr4 and PEA2PbBr4, respectively, compared to those of undoped crystals. The inclusion of Rb ions also leads to a slightly longer afterglow, with residual scintillation still being below 1% after 5 s at 10 K, for both undoped and Rb-doped perovskite crystals. The light yield of both perovskites is significantly increased by Rb doping with improvements of 58% and 25% for BA2PbBr4 and PEA2PbBr4, respectively. This work shows that Rb doping leads to a significant enhancement of the 2D-HOIP crystal performance, which is of particular significance for high light yield and fast timing applications, such as photon counting or positron emission tomography.

14.
Phys Chem Chem Phys ; 25(45): 31374-31381, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37961857

RESUMO

Cation migration coupled with oxygen vacancy formation is known to drive the layered to disordered spinel/rock-salt phase transformation in the high-Ni layered oxide cathodes of Li-ion batteries. However, the effect of different electronic states of oxygen vacancies on the cation migration still remains elusive. Here, we investigate Ni migration in delithiated Ni-rich Li0.5Ni0.8Mn0.1Co0.1O2 (hence Li0.5NMC811) in the presence of neutral and charged oxygen vacancies by means of first-principles density functional theory (DFT) calculations coupled with the nudged elastic band (NEB) method. We find that oxygen vacancies with neutral or +2 charge favor the Ni migration to Li tetrahedral and/or octahedral sites, both thermodynamically and kinetically. As for the case of +1 charged oxygen vacancies, while they thermodynamicaly favor the Ni migration to the Li site, the relatively high migration barrier suggests that they kinetically prohibit the Ni migration. Our results suggest that controlling the formation of oxygen vacancies is the key to enhancing the Ni-rich NMC structural stability in particular in their charged states.

15.
Perfusion ; 38(3): 645-650, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-34927476

RESUMO

INTRODUCTION: Extracorporeal membrane oxygenation (ECMO) is a well-recognized therapy in children with refractory hypoxia. Different cannulas have been used with reported complications with placement, such as cardiac perforation, and multiple reports focusing on avoiding this. However, strategies to avoid hepatic vein cannulation and reposition when it occurs are not well described. CASE REPORT: Here, we report a case where a 27-Fr Avalon bicaval double lumen cannula in the left hepatic vein was successfully repositioning using serial chest X-rays (CXR) and transthoracic echocardiography (TTE) in a 17-year-old female. DISCUSSION: While venovenous (VV) ECMO is preferred by many, placement of the Avalon catheter, a cannula available for VV ECMO, may be challenging due to migration or positioning issues. Specific techniques of wire and catheter advancement as well as confirming wire position in the infra-hepatic inferior vena cava can help ensure appropriate positioning while avoiding hepatic vein cannulation and enabling successful repositioning when it occurs. CONCLUSION: Wire position in the infra-hepatic inferior vena cava helps ensure safe and appropriate Avalon cannula position and placement. The Avalon cannula can be successfully repositioned from the left hepatic vein by retracting the cannula, reinserting the wire and introducer together, and then manipulation techniques using serial CXR and TTE.


Assuntos
Cânula , Oxigenação por Membrana Extracorpórea , Criança , Feminino , Humanos , Adolescente , Veias Hepáticas , Oxigenação por Membrana Extracorpórea/métodos , Catéteres , Cateterismo/métodos
16.
Phys Chem Chem Phys ; 24(7): 4196-4203, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35119442

RESUMO

Understanding the factors that influence the activity of a catalyst toward CH4 activation is of high importance for tuning the catalyst performance or designing new, better catalysts. Here, we performed a set of density functional theory (DFT) calculations on the H-CH3 bond cleavage over the Cu-O-Cu active site in the MOR zeolite with various Al-pair arrangements to obtain molecular insight into the structure-activity relation and clarify key parameters that define the Cu-O-Cu reactivity toward CH4. We found that weakening of the Cu-O-Cu bond during CH4 activation is crucial for determining the O-H bond strength and thus the Cu-O-Cu reactivity. In this regard, the zeolite lattice constraints are found to play a significant role as, on the one hand, it strengthens the Cu⋯Cu interaction and consequently weakens the Cu-O-Cu bonds and, on the other hand, it forces the Cu-O-Cu bond elongation process to destabilize the active site structure. The non-planar Cu-O-Cu geometry, due to lattice constraints, is also found to make the CH4 adsorption site, whether positioned closer to the µ-O or the Cu atom, crucial in determining the C-H activation product, i.e., a ˙CH3 radical or a Cu2-CH3- ligand.

17.
Am J Otolaryngol ; 43(1): 103204, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34537511

RESUMO

BACKGROUND: Thyroid nodules are commonly being diagnosed in general population and have a potential for malignant transformation. Historically, surgery has been considered as the first line treatment for these tumors. However, with passage of time newer minimally invasive techniques such as RFA (radiofrequency ablation) has been adapted. Though, RFA for thyroid tumors has been performed more commonly in Asian and European countries, it is a fairly new technique in North America. The aim of the review is to assess the current data and conclude that whether RFA is likely a valuable option when compared to surgery for treatment of thyroid tumors. MATERIALS AND METHODS: A Comprehensive PubMed/MEDLINE, Embase and Web of Science search was performed. To expand our search, references of the retrieved articles were also screened for additional data. After selecting the studies that fulfilled the initial screening, authors independently reviewed the selected studies and screened the full texts to identify those that met the inclusion criteria. RESULTS: The comprehensive literature search from PubMed/MEDLINE, Web of Science, and EMBASE databases revealed 1094 studies (Embase 870, PubMed 200, and Web of Science 24). References were imported for screening. Amongst 1094 studies, 138 duplicates removed, and 956 studies were screened against title and abstract. After these 777 studies were excluded the remaining 179 studies were assessed for full-text eligibility. Amongst them 127 studies excluded due to wrong design or setting. Finally, 18 studies were included in the review. CONCLUSION: RFA appears to be a safe alternative to surgery in selected cases. However, it is not widely used and there are few randomized controlled trials. Furthermore, it is associated with a low risk profile and has shown promising results in patients who are difficult surgery candidates. Currently large-scale prospective studies are needed in North America to establish the efficacy of RFA and its use as an alternative to surgery for thyroid tumors.


Assuntos
Ablação por Radiofrequência/métodos , Neoplasias da Glândula Tireoide/cirurgia , Transformação Celular Neoplásica , Feminino , Humanos , Masculino , Nódulo da Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/cirurgia , Resultado do Tratamento
18.
BMC Med Educ ; 22(1): 534, 2022 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-35810272

RESUMO

BACKGROUND: Cross-cultural competence is widely regarded to play an important role in being able to deliver appropriate and effective health care to patients with different backgrounds, race, gender orientation and cultural beliefs. This study aims to assess how medical students feel about their comfort, knowledge, and skill level in handling a diverse patient population using a validated questionnaire. METHODS: This study was carried out over a period of three weeks from July 5th to July 26th of 2021, in the Aga Khan University Hospital, Karachi, Pakistan. All medical students who fulfilled the eligibility criteria and gave informed consent were included in the study. A modified version of the Harvard cross-cultural care survey was used to assess the medical students' comfort, knowledge and skill level in a variety of circumstances related to patients with different backgrounds and cultures. Descriptive statistical analysis of the questionnaire items was carried out. We reported frequencies and percentages for gender and year of study. For the questionnaire items, we reported mean, assuming that our Likert scale had equivariant intervals. Furthermore, multivariate analysis between demographics and themes was carried out. A p-value of < 0.05 was taken as statistically significant. RESULTS: It was found that students of year 5 considered themselves more knowledgeable, comfortable and skilled in dealing with patients of different backgrounds, religions and beliefs compared to students of year 1 and had a higher average score in all of these categories which was statistically significant. Additionally, students who believed it is extremely important to practice medicine with a diverse patient population also had the highest averages in perceived knowledge, comfort and skills in dealing with patients of different sociocultural backgrounds compared to students who believed it wasn't important at all. CONCLUSION: This is a first of its kind study in a private medical university in Pakistan and highlights the students' self-assessment of their competence when caring for patients from different backgrounds. This study can be used as a reference study in the region to carry out further studies and to assess and improve the gaps in medical training being provided.


Assuntos
Competência Cultural , Estudantes de Medicina , Competência Cultural/educação , Assistência à Saúde Culturalmente Competente , Humanos , Percepção , Inquéritos e Questionários
19.
Ergonomics ; 65(5): 704-718, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34544328

RESUMO

The health and working environment of bus drivers is compromised in low-middle-income countries like Pakistan which leads to burnout and excessive Road Traffic Crashes. Hence, this study delves into factors affecting their safe operations from health and work environment perspectives and measures their associated stress and Burnout level. In a study of four hundred and ninety-nine (499), 86% city and 14% transit bus drivers are surveyed through a questionnaire. Stress is estimated for city and transit bus drivers, using the Effort/Reward Imbalance Model (ERI) of Siegrist, and burnout is calculated using the Copenhagen Burnout Inventory (CBI). For the determination of important determinants, descriptive and regression analyses are conducted. Findings show that stress has emerged as a negative factor for the physical and psychological health of city and transit bus drivers. Results based on bus drivers' responses suggest that organisational awareness and emphasis on health and safety levels can significantly reduce driver stress and burnout. Practitioner Summary: This study explores burnout and work-related stress of bus drivers in Lahore (Pakistan). City and transit bus drivers were interviewed through a questionnaire, containing three sections, using different subjective ratings based upon their past reliability. Results indicate that stress in bus drivers emerged as a physical and psychological health-damaging factor.


Assuntos
Condução de Veículo , Esgotamento Profissional , Estresse Ocupacional , Ergonomia , Humanos , Paquistão/epidemiologia , Reprodutibilidade dos Testes , Sono
20.
J Environ Sci Health B ; 57(12): 932-947, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36469565

RESUMO

Pesticides present in their commercial formulations are studied for their preferable binding toward carbon-based graphene oxide (GO) or transition metal nanoparticles (Fe, Co, Ni, and Cu), present as hybrids. This simple study also reveals the mechanism of interaction of few selected different classes of pesticides, namely, λ-cyhalothrin, imidacloprid, and metsulfuron-methyl toward these hybrids. Individually, to study this comparative binding when hybrids are not used, the understanding of preferred binding toward any of these selected compounds could be challenging, costly, and time-consuming. Dynamic light scattering (DLS) is used to study the changes observed for hydrodynamic radius and zeta potential for the stability of the resulting products. This simple method can also be extended to identify the binding mechanism for other diverse set of combinations. These studies are supported by binding of GO with nanoparticles in batch adsorption and the best fit using Langmuir and Freundlich isotherms is presented. Moreover, pesticide adsorption toward GO-nanoparticle composites is also evidenced.


Assuntos
Grafite , Nanopartículas Metálicas , Praguicidas , Difusão Dinâmica da Luz , Nanopartículas Metálicas/química , Grafite/química
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