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1.
J Anat ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39022807

RESUMO

Recent evidence suggests that the invasive air sac system evolved at least three times independently in avemetatarsalians: in pterosaurs, sauropodomorphs and theropods. Data from sauropodomorphs showed that the pneumatic architecture in vertebrae first developed in camellate-like trabeculae in the Triassic, later in camerate systems in Jurassic neosauropods, and finally camellate tissue in Cretaceous titanosaurs. This evolutionary trajectory has support from a considerable sampling of sauropodomorph taxa. However, the evolution of pneumatic bone tissues in Theropoda is less understood. We analyzed the computed tomography of Majungasaurus and Rahonavis, using densitometry rendering to differentiate the microarchitecture along the presacral axial skeleton of late Ceratosaurians and early Paravians. We also compared these results with scans of other theropod clades. Our analysis revealed an increase in pneumatic complexity in early paravians compared to the ceratosaurians. Majungasaurus presents some apneumatic neural spines, a condition also observed in Allosaurus. Majungasaurus also features some apneumatic centra despite the presence of lateral pneumatic fossae. This raises caution when evaluating PSP solely based on external morphology. We also found evidence of distinct patterns of PSP in maniraptorans. Considering that Majungasaurus, a late abelisaurid, inherited from their ceratosaurian ancestors, some apneumatic elements such as the neural spine and some centra, Rahonavis, an early paravian, took a different trajectory toward the full pneumatization of the axial skeleton. This characteristic provided paravians an advantage in gliding and flying. Also, unlike Sauropoda, pneumaticity in Theropoda apparently developed by increasing chamber volumes toward paravians. Similar studies on early Theropoda are needed to elucidate their condition and better describe the evolutionary trajectory of different groups.

2.
Respir Care ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39013568

RESUMO

BACKGROUND: PEEP is a cornerstone treatment for children with pediatric ARDS. Unfortunately, its titration is often performed solely by evaluating oxygen saturation, which can lead to inadequate PEEP level settings and consequent adverse effects. This study aimed to assess the impact of increasing PEEP on hemodynamics, respiratory system mechanics, and oxygenation in children with ARDS. METHODS: Children receiving mechanical ventilation and on pressure-controlled volume-guaranteed mode were prospectively assessed for inclusion. PEEP was sequentially changed to 5, 12, 10, 8 cm H2O, and again to 5 cm H2O. After 10 min at each PEEP level, hemodynamic, ventilatory, and oxygenation variables were collected. RESULTS: A total of 31 subjects were included, with median age and weight of 6 months and 6.3 kg, respectively. The main reasons for pediatric ICU admission were respiratory failure caused by acute viral bronchiolitis (45%) and community-acquired pneumonia (32%). Most subjects had mild or moderate ARDS (45% and 42%, respectively), with a median (interquartile range) oxygenation index of 8.4 (5.8-12.7). Oxygen saturation improved significantly when PEEP was increased. However, although no significant changes in blood pressure were observed, the median cardiac index at PEEP of 12 cm H2O was significantly lower than that observed at any other PEEP level (P = .001). Fourteen participants (45%) experienced a reduction in cardiac index of > 10% when PEEP was increased to 12 cm H2O. Also, the estimated oxygen delivery was significantly lower, at 12 cm H2O PEEP. Finally, respiratory system compliance significantly reduced when PEEP was increased. At a PEEP of 12 cm H2O, static compliance had a median reduction of 25% in relation to the initial assessment (PEEP of 5 cm H2O). CONCLUSIONS: Although it may improve arterial oxygen saturation, inappropriately high PEEP levels may reduce cardiac output, oxygen delivery, and respiratory system compliance in pediatric subjects with ARDS with low potential for lung recruitability.

3.
Radiol Bras ; 57: e20230079en, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38993970

RESUMO

Objective: To evaluate the correlation between multidetector computed tomography (MDCT) findings and laboratory test results in patients with pulmonary tuberculosis (PTB). Materials and Methods: A total of 57 patients were evaluated. Patients with suspected PTB were divided into groups according to the final diagnosis (confirmed or excluded), and the groups were compared in terms of sociodemographic variables, clinical symptoms, tomography findings, and laboratory test results. Results: Among the patients with a confirmed diagnosis of PTB, small pulmonary nodules with a peribronchovascular distribution were significantly more common in the patients with a positive sputum smear microscopy result (47.4% vs. 8.3%; p = 0.046), as were a miliary pattern (36.8% vs. 0.0%; p = 0.026), septal thickening (84.2% vs. 41.7%; p = 0.021), and lymph node enlargement (52.6% vs. 8.3%; p = 0.020). Small pulmonary nodules with a centrilobular distribution were significantly more common among the culture-positive patients (75.0% vs. 35.7%; p = 0.045), as was a tree-in-bud pattern (91.7% vs. 42.9%; p = 0.014). A tree-in-bud pattern, one of the main tomography findings characteristic of PTB, had a sensitivity, specificity, positive predictive value, and negative predictive value of 71.0%, 73.1%, 75.9%, and 67.9%, respectively. Conclusion: MDCT presented reliable predictive values for the main tomography findings in the diagnosis of PTB, being a safe tool for the diagnosis of PTB in patients with clinical suspicion of the disease. It also appears to be a suitable tool for the selection of patients who are candidates for more complex, invasive examinations from among those with high clinical suspicion of PTB and a negative sputum smear microscopy result.


Objetivo: Avaliar a correlação entre os achados na tomografia computadorizada multidetectores (TCMD) comparativamente aos resultados laboratoriais em pacientes com tuberculose pulmonar (TBP). Materiais e Métodos: Amostra de 57 pacientes foi avaliada. Pacientes com suspeita clínica de TBP foram divididos de acordo com a positividade do diagnóstico, e as variáveis sociodemográficas, sintomas clínicos e achados tomográficos e laboratoriais foram comparados. Resultados: Nos pacientes com TBP e baciloscopia positiva, foram verificadas frequências significativas para pequenos nódulos pulmonares com distribuição peribroncovascular (47,4% vs. 8,3%; p = 0,046) e miliar (36,8% vs. 0,0%; p = 0,026), espessamento septal (84,2% vs. 41,7%; p = 0,021) e linfonodomegalias (52,6% vs. 8,3%; p = 0,020). Em relação à cultura, os pequenos nódulos pulmonares com distribuição centrolobular (75,0% vs. 35,7%; p = 0,045) e opacidades em árvore em brotamento (91,7% vs. 42,9%; p = 0,014) apresentaram frequências significativamente superiores. Medidas de sensibilidade, especificidade, valor preditivo positivo e valor preditivo negativo para árvore em brotamento, um dos principais achados tomográficos característicos da TBP, foram, respectivamente, 71.0%, 73,1%, 75,9% e 67,9%. Conclusão: A TCMD apresentou medidas preditivas confiáveis para os principais achados tomográficos no diagnóstico de TBP, sendo uma ferramenta segura para o diagnóstico da doença em pacientes com suspeita clínica. Também se mostrou adequada para selecionar os pacientes para exames mais complexos e invasivos entre os com alta suspeita clínica de TBP e baciloscopia negativa.

4.
Adv Respir Med ; 92(4): 278-290, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39051189

RESUMO

AIM: Physical activity attenuates hypertension in older adults, but its impact on pulmonary function and mechanics in hypertensive older adults is unknown. The study seeks to understand whether a physically active lifestyle can improve respiratory capacity, the mechanical efficiency of the lungs, and, consequently, the quality of life of these individuals, comparing data between groups of active and sedentary hypertensive older adults. METHODS: This is a cross-sectional study. We evaluated 731 older adults, stratified into two initial groups: hypertensive older adults (HE; n = 445) and non-hypertensive older adults (NHE; n = 286). For a secondary analysis, we used the International Physical Activity Questionnaire to sub-stratify HE and NHE into four groups: physically inactive hypertensive (PIH; n = 182), active hypertensive (AH; n = 110), physically inactive non-hypertensive (PINH; n = 104), and active non-hypertensive (ANH; n = 65). Lung function was measured by spirometry, and lung mechanics were assessed by impulse oscillometry. RESULTS: Hypertensive older adults presented reduced lung function compared to non-hypertensive older adults, and physical inactivity accentuated this decline. Regarding pulmonary mechanics, hypertensive older adults had higher resistance of the entire respiratory system (R5 Hz), the central airways (R20 Hz), and peripheral airways (R5-20 Hz), which may trigger bronchoconstriction. CONCLUSIONS: Hypertension is associated with impaired lung function and mechanics in older adults, and a physically active lifestyle attenuates these dysfunctions.


Assuntos
Exercício Físico , Hipertensão , Humanos , Hipertensão/fisiopatologia , Estudos Transversais , Idoso , Masculino , Exercício Físico/fisiologia , Feminino , Testes de Função Respiratória , Mecânica Respiratória/fisiologia , Pulmão/fisiopatologia , Qualidade de Vida , Pessoa de Meia-Idade
5.
Int J Nurs Knowl ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951045

RESUMO

OBJECTIVE: To analyze the accuracy of the defining characteristics of four respiratory nursing diagnoses (ND) in patients with COVID-19 and on oxygen therapy. METHODS: This is a cross-sectional study conducted in four Brazilian public hospitals in two regions of the country. A total of 474 patients with COVID-19 receiving oxygen therapy were assessed. Latent-adjusted class analysis with random effects was used to establish the sensitivity (Se) and specificity (Sp) of the defining characteristics evaluated for each ND. RESULTS: Among the ND that constituted the study (impaired spontaneous ventilatory, impaired gas exchange, ineffective airway clearance, and dysfunctional ventilatory weaning response), the following defining characteristics had the highest simultaneous Se and Sp (>0.8): decrease in tidal volume, confusion, irritability, dyspnea, decreased breath sounds, orthopnea, impaired ability to cooperate and respond to coaching, and decrease in the level of consciousness. CONCLUSIONS: Recognizing the clinical signs that predict respiratory ND in patients affected by COVID-19 can contribute to the nurse's accurate diagnostic inference and designate the appropriate nursing interventions to achieve the desired results and avoid complications.


OBJETIVO: Analisar a acurácia das características definidoras de quatro Diagnósticos de Enfermagem (DE) respiratórios em pacientes com COVID­19 e em uso de oxigenoterapia. MÉTODOS: Estudo transversal, realizado em quatro hospitais públicos brasileiros de duas regiões do país. Foram avaliados 474 pacientes diagnosticados com COVID­19 e em uso de oxigenoterapia. A análise de classe latente ajustada com efeitos randômicos foi utilizada para estabelecer a sensibilidade (Se) e especificidade (Sp) das características definidoras avaliadas para cada DE. RESULTADOS: As características definidoras volume corrente diminuído, confusão, irritabilidade, dispneia, sons respiratórios diminuídos, ortopneia, capacidade prejudicada para cooperar e responder orientações, e nível de consciência diminuído foram as que obtiveram maior sensibilidade e especificidade simultaneamente (> 0.8) dentre os diagnósticos de enfermagem compuseram o estudo: Ventilação espontânea prejudicada, Resposta disfuncional ao desmame, Desobstrução ineficaz das vias aéreas e Troca de gases prejudicada. CONCLUSÕES: Conhecer os sinais clínicos preditores dos diagnósticos de enfermagem respiratórios em pacientes acometidos por COVID­19 pode contribuir para a inferência diagnóstica acurada do enfermeiro e designar as intervenções de enfermagem apropriadas para atingir os resultados desejados e evitar complicações.

6.
J Exp Biol ; 227(6)2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38426596

RESUMO

Teiid lizards possess an incomplete post-hepatic septum (PHS) separating the lungs and liver from the remaining viscera, and within this group, Salvator merianae has the most complete PHS. In this study, we explored the combined effects of the presence of the PHS and alterations in abdominal volume on the mechanics of the respiratory system. The PHS is believed to act as a mechanical barrier, mitigating the impact of the viscera on the lungs. Using established protocols, we determined static (Cstat) and dynamic (Cdyn) compliance, lung volume and work of breathing for the respiratory system in tegu lizards with intact (PHS+) or removed (PHS-) PHS, combined with (balloon+) or without (balloon-) increased abdominal volume. The removal of the PHS significantly reduced resting lung volume and Cdyn, as well as significantly increasing the work of breathing. An increase in abdominal volume significantly reduced Cstat, Cdyn, and resting and maximum lung volume. However, the work of breathing increased less in the PHS+/balloon+ treatment than in the PHS- treatments. These results highlight the barrier function of the PHS within the tegu lizard's body cavity. The septum effectively reduces the impact of the viscera on the respiratory system, enabling the lungs to be ventilated at a low work level, even when abdominal volume is increased. The presence of the PHS in teiid lizards underscores how extrapulmonary structures, such as septal divisions of the body cavity, can profoundly affect pulmonary breathing mechanics.


Assuntos
Lagartos , Animais , Fígado , Pulmão , Respiração , Mecânica Respiratória
7.
Neurocrit Care ; 41(1): 272-284, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38396279

RESUMO

Neurocritical patients (NCPs) in the intensive care unit (ICU) rapidly progress to respiratory and peripheral muscle dysfunctions, which significantly impact morbidity and death. Early mobilization in NCPs to decrease the incidence of ICU-acquired weakness has been showing rapid growth, although pertinent literature is still scarce. With this review, we summarize and discuss current concepts in early mobilization of critically ill patients within the context of neurologic pathology in NCPs. A narrative synthesis of literature was undertaken trying to answer the following questions: How do the respiratory and musculoskeletal systems in NCPs behave? Which metabolic biomarkers influence physiological responses in NCPs? Which considerations should be taken when prescribing exercises in neurocritically ill patients? The present review detected safety, feasibility, and beneficial response for early mobilization in NCPs, given successes in other critically ill populations and many smaller intervention trials in neurocritical care. However, precautions should be taken to elect the patient for early care, as well as monitoring signs that indicate interruption for intervention, as worse outcomes were associated with very early mobilization in acute stroke trials.


Assuntos
Estado Terminal , Deambulação Precoce , Humanos , Cuidados Críticos , Doenças do Sistema Nervoso/terapia , Unidades de Terapia Intensiva
8.
Anat Rec (Hoboken) ; 307(4): 1084-1092, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36971057

RESUMO

One of the most remarkable features in sauropod dinosaurs relates to their pneumatized skeletons permeated by a bird-like air sac system. Many studies described the late evolution and diversification of this trait in mid to late Mesozoic forms but few focused on the origin of the invasive respiratory diverticula in sauropodomorphs. Fortunately, it is possible to solve this thanks to the boom of new species described in the last decade as well as the broad accessibility of new technologies. Here we analyze the unaysaurid sauropodomorph Macrocollum itaquii from the Late Triassic (early Norian) of southern Brazil using micro-computed tomography. We describe the chronologically oldest and phylogenetically earliest unambiguous evidence of an invasive air sac system in a dinosaur. Surprisingly, this species presented a unique pattern of pneumatization in non-sauropod sauropodomorphs, with pneumatic foramina in posterior cervical and anterior dorsal vertebrae. This suggests that patterns of pneumatization were not cladistically consistent prior to the arrival of Jurassic eusauropods. Additionally, we describe the protocamerae tissue, a new type of pneumatic tissue with properties of both camellae and camerae. This reverts the previous hypothesis which stated that the skeletal pneumatization first evolved into camarae, and derived into delicate trabecular arrangements. This tissue is evidence of thin camellate-like tissue developing into larger chambers. Finally, Macrocollum is an example of the gradual evolution of skeletal tissues responding to the fastly specializing Respiratory System of saurischian dinosaurs.


Assuntos
Sacos Aéreos , Dinossauros , Animais , Evolução Biológica , Dinossauros/anatomia & histologia , Microtomografia por Raio-X , Fósseis , Filogenia
9.
Radiol. bras ; 57: e20230079en, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1558823

RESUMO

Abstract Objective: To evaluate the correlation between multidetector computed tomography (MDCT) findings and laboratory test results in patients with pulmonary tuberculosis (PTB). Materials and Methods: A total of 57 patients were evaluated. Patients with suspected PTB were divided into groups according to the final diagnosis (confirmed or excluded), and the groups were compared in terms of sociodemographic variables, clinical symptoms, tomography findings, and laboratory test results. Results: Among the patients with a confirmed diagnosis of PTB, small pulmonary nodules with a peribronchovascular distribution were significantly more common in the patients with a positive sputum smear microscopy result (47.4% vs. 8.3%; p = 0.046), as were a miliary pattern (36.8% vs. 0.0%; p = 0.026), septal thickening (84.2% vs. 41.7%; p = 0.021), and lymph node enlargement (52.6% vs. 8.3%; p = 0.020). Small pulmonary nodules with a centrilobular distribution were significantly more common among the culture-positive patients (75.0% vs. 35.7%; p = 0.045), as was a tree-in-bud pattern (91.7% vs. 42.9%; p = 0.014). A tree-in-bud pattern, one of the main tomography findings characteristic of PTB, had a sensitivity, specificity, positive predictive value, and negative predictive value of 71.0%, 73.1%, 75.9%, and 67.9%, respectively. Conclusion: MDCT presented reliable predictive values for the main tomography findings in the diagnosis of PTB, being a safe tool for the diagnosis of PTB in patients with clinical suspicion of the disease. It also appears to be a suitable tool for the selection of patients who are candidates for more complex, invasive examinations from among those with high clinical suspicion of PTB and a negative sputum smear microscopy result.


Resumo Objetivo: Avaliar a correlação entre os achados na tomografia computadorizada multidetectores (TCMD) comparativamente aos resultados laboratoriais em pacientes com tuberculose pulmonar (TBP). Materiais e Métodos: Amostra de 57 pacientes foi avaliada. Pacientes com suspeita clínica de TBP foram divididos de acordo com a positividade do diagnóstico, e as variáveis sociodemográficas, sintomas clínicos e achados tomográficos e laboratoriais foram comparados. Resultados: Nos pacientes com TBP e baciloscopia positiva, foram verificadas frequências significativas para pequenos nódulos pulmonares com distribuição peribroncovascular (47,4% vs. 8,3%; p = 0,046) e miliar (36,8% vs. 0,0%; p = 0,026), espessamento septal (84,2% vs. 41,7%; p = 0,021) e linfonodomegalias (52,6% vs. 8,3%; p = 0,020). Em relação à cultura, os pequenos nódulos pulmonares com distribuição centrolobular (75,0% vs. 35,7%; p = 0,045) e opacidades em árvore em brotamento (91,7% vs. 42,9%; p = 0,014) apresentaram frequências significativamente superiores. Medidas de sensibilidade, especificidade, valor preditivo positivo e valor preditivo negativo para árvore em brotamento, um dos principais achados tomográficos característicos da TBP, foram, respectivamente, 71.0%, 73,1%, 75,9% e 67,9%. Conclusão: A TCMD apresentou medidas preditivas confiáveis para os principais achados tomográficos no diagnóstico de TBP, sendo uma ferramenta segura para o diagnóstico da doença em pacientes com suspeita clínica. Também se mostrou adequada para selecionar os pacientes para exames mais complexos e invasivos entre os com alta suspeita clínica de TBP e baciloscopia negativa.

10.
Acta cir. bras ; 39: e390324, 2024. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1533359

RESUMO

Purpose: The current study aimed at evaluating the repair of a partial defect of the trachea with a muscle flap, an advanced technique that employs combined suture patterns. Methods: Sixteen healthy male New Zealand white rabbits were used as an experimental model. A partial defect in the trachea within the ventral region of the fourth to eighth tracheal ring was created. Subsequently, repair was initiated with a flap of the sternocephalicus muscle. The animals were divided into four groups for postoperative evaluation using clinical, tracheoscopic, and histopathological analyses. Each group was separated according to the time of euthanasia, programmed at interval of seven (G7), 15 (G15), 30 (G30), and 60 days (G60). Results: One animal from the G60 group died, whereas the other animals had good surgical recovery without serious changes in the breathing pattern. The major clinical signs observed were stridor and coughing. Tracheoscopy revealed secretions in the tracheal lumen, exuberant granulation, and stenosis. Histopathological analysis showed growth of the ciliary respiratory epithelium at the flap site 30 days after implantation. Conclusions: Partial repair showed satisfactory results owing to the anatomical location of the muscle, adequate vascular support, and structural and physiological maintenance without serious changes in the respiratory system.


Assuntos
Animais , Coelhos , Coelhos/cirurgia , Retalhos Cirúrgicos/veterinária , Doenças da Traqueia/veterinária , Endoscopia/veterinária
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