ABSTRACT
ABSTRACT Vitamin D is a pleiotropic steroid hormone that modulates the autonomic balance. Its deficiency has been described as an environmental risk factor for multiple sclerosis (MS). The aim of this study was to investigate the serum levels of vitamin D, vitamin D binding protein (VDBP) and vitamin D receptors (VDR) and to evaluate cardiac dysautonomia in MS patients due to bidirectional interaction between vitamin D and the autonomic nervous system. Methods: The current cross-sectional study was conducted on 26 patients with relapsing-remitting MS and on 24 healthy controls. Twenty-four-hour ambulatory blood pressure variability (BPV) was calculated and the participants were evaluated for orthostatic hypotension and supine hypertension. Serum levels of vitamin D, VDBP and VDR were measured. Results: The mean serum vitamin D level was significantly lower in MS patients than in controls (p = 0.044); however there was no significant difference in terms of VDR and VDBP levels between the groups. Supine hypertension and orthostatic hypotension were significant and the 24-hour systolic BPV was significantly decreased in patients with MS (p < 0.05) compared to controls. No correlation was found between vitamin D, VDBP and VDR with supine hypertension, orthostatic hypotension and systolic BPV values (p > 0.05). Also, there was a negative correlation between VDBP and the EDSS (p = 0.039, r = −0.406). Conclusion: There was no correlation between orthostatic hypotension, supine hypertension and systolic BPV values and serum vitamin D, VDBP and VDR in MS patients. Future prospective studies with large number of patients may help us to better understand the relationship between vitamin D and the autonomic nervous system.
RESUMO A vitamina D é um hormônio esteroide pleiotrópico que modula o equilíbrio autonômico. Sua deficiência tem sido descrita como fator de risco ambiental para esclerose múltipla (EM). O objetivo deste estudo foi investigar os níveis séricos de vitamina D, proteína de ligação à vitamina D (VDBP) e receptor de vitamina D (VDR) e avaliar a disautonomia cardíaca em pacientes com EM devida à interação bidirecional entre vitamina D e sistema nervoso autônomo. Métodos: O presente estudo transversal foi realizado em 26 pacientes com EM remitente-recorrente e em 24 controles saudáveis. A variabilidade da pressão arterial ambulatorial (BPV) por 24 horas foi calculada e os participantes foram avaliados quanto à hipotensão ortostática e hipertensão supina. Os níveis séricos de vitamina D, VDBP e VDR foram medidos. Resultados: O nível sérico médio de vitamina D foi significativamente menor nos pacientes com EM do que nos controles (p = 0,044); no entanto, não houve diferença significativa em termos de níveis de VDR e VDBP entre os grupos. Hipertensão supina e hipotensão ortostática foram significativas e a BPV sistólica de 24 horas diminuiu significativamente em pacientes com EM (p < 0,05) em comparação aos controles. Não foi encontrada correlação entre vitamina D, VDBP e VDR com hipertensão supina, hipotensão ortostática e BPV sistólica (p > 0,05). Também houve correlação negativa entre VDBP e EDSS (p = 0,039, r = −0,406). Conclusão: Não houve correlação entre hipotensão ortostática, hipertensão supina e valores de BPV sistólica e vitamina D sérica, VDBP e VDR em pacientes com EM. Futuros estudos prospectivos com grande número de pacientes podem nos ajudar a entender melhor a relação entre vitamina D e sistema nervoso autônomo.
Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Young Adult , Autonomic Nervous System Diseases/blood , Vitamin D/blood , Vitamin D-Binding Protein/blood , Receptors, Calcitriol/blood , Multiple Sclerosis, Relapsing-Remitting/blood , Primary Dysautonomias/blood , Reference Values , Autonomic Nervous System Diseases/physiopathology , Vitamin D Deficiency/complications , Vitamin D Deficiency/blood , Blood Pressure/physiology , Enzyme-Linked Immunosorbent Assay , Case-Control Studies , Cross-Sectional Studies , Risk Factors , Supine Position/physiology , Statistics, Nonparametric , Multiple Sclerosis, Relapsing-Remitting/physiopathology , Primary Dysautonomias/etiology , Primary Dysautonomias/physiopathology , Heart Rate/physiology , Hypertension/physiopathology , Hypertension/blood , Hypotension, Orthostatic/physiopathology , Hypotension, Orthostatic/bloodABSTRACT
ABSTRACT Obstructive sleep apnea (OSA) occurs in up to 66% of Parkinson's disease (PD) patients, higher than in the general population. Although it is more prevalent, the relationship between OSA and PD remains controversial, with some studies confirming and others denying the relationship of OSA with some risk factors and symptoms in patients with PD. Objective: To determine the factors associated with OSA in PD patients com DP. Methods: A cross-sectional study was performed with 88 consecutive patients with PD from the outpatient clinic. Participants underwent clinical interviews with neurologists and a psychiatrist, assessment using standardized scales (Epworth Sleepiness Scale, Parkinson's Disease Questionnaire, Pittsburgh Sleep Quality Index and, for individuals with a diagnosis of restless legs syndrome/Willis-Ekbom disease, the International Restless Legs Syndrome Rating Scale), and video-polysomnography. Results: Individuals with PD and OSA were older and had less insomnia than those with PD without OSA. Regarding the polysomnographic variables, we observed a lower percentage of stage N3 sleep, a higher arousal index, and a higher oxygen desaturation index in those individuals with OSA, relative to those without OSA. In the multivariate analysis, only the percentage of stage N3 sleep and the oxygen desaturation index were significantly different. Besides this, most of the PD patients with OSA had a correlation with sleeping in the supine position (58% of OSA individuals). Conclusion: The PD patients showed a high prevalence of OSA, with the supine position exerting a significant influence on the OSA in these patients, and some factors that are associated with OSA in the general population did not seem to have a greater impact on PD patients.
RESUMO A Apneia Obstrutiva do Sono (AOS) chega a acometer até 66% dos pacientes com doença de Parkinson (DP), prevalência maior, portanto, que a da população geral. Embora seja mais prevalente, a relação entre AOS e DP permanence controversa, com trabalhos confirmando e outros afastando a relação de AOS com alguns fatores de risco e sintomas em pacientes com DP. Objetivo: Determinar quais fatores estão relacionados à AOS em pacientes com DP. Métodos: Estudo transversal, observacional, realizado com 88 pacientes com DP, provenientes do ambulatório de hospital público. Os pacientes foram submetidos à entrevista clínica com neurologista e psiquiatra, à aplicação de escalas padronizadas (escala de sonolência de Epworth, questionário de qualidade de vida da DP, índice de qualidade de sono de Pittsburgh e, para os indivíduos com diagnóstico de Síndrome das Pernas Inquietas, a escala internacional de graduação da SPI), e vídeo-polissonografia. Resultados: Indivíduos com DP e AOS apresentaram maior idade e menor prevalência de insônia crônica que os indivíduos com DP, sem AOS. Em relação às variáveis polissonográficas, observamos uma baixa proporção de sono N3, elevado índice de microdespertares e maior índice de desaturações nos indivíduos com AOS, em comparação ao grupo sem AOS. Na análise multivariada, apenas a porcentagem de sono N3 e o índice de dessaturação permaneceu significativo. Além disso, a maior parte dos pacientes tem relação com a posição supina (58% dos pacientes com AOS). Conclusão: Pacientes com DP apresentaram prevalência elevada de AOS, a posição supina exerceu influência importante na AOS destes pacientes e alguns fatores que estão associados à AOS na população geral não mostraram impacto significativo nos pacientes com DP.
Subject(s)
Humans , Male , Female , Middle Aged , Aged , Parkinson Disease/complications , Parkinson Disease/epidemiology , Sleep Apnea, Obstructive/complications , Sleep Apnea, Obstructive/epidemiology , Quality of Life , Sleep Stages/physiology , Time Factors , Brazil/epidemiology , Cross-Sectional Studies , Multivariate Analysis , Surveys and Questionnaires , Risk Factors , Supine Position/physiology , Polysomnography , Statistics, NonparametricABSTRACT
Abstract Objective: The aim of the present study was to investigate the acute response to aerobic exercise on autonomic cardiac control of patients undergoing coronary artery bypass grafting (CABG). Methods: The study sample consisted of eight patients (age: 58.6±7.7 years; body mass index: 26.7±3.5 kg.m2) who underwent a successful CABG (no complications during surgery and/or in the following weeks). To assess heart rate variability (HRV), participants remained in a supine position with a 30-degree head elevation for 20 minutes. Electrocardiographic signal (protocol with three derivations) was collected from 600 Hz sample rate to obtain beat-to-beat intervals (R-R interval). This assessment was performed before, after one hour and after 24 hours of the exercise session. All patients underwent a 35 minutes aerobic exercise session (AES) (low-moderate intensity) on the cycle ergometer. Results: Significant differences were found in the time domain, with positive changes in root mean square of successive RR interval differences (rMSSD) (ms) (parasympathetic component) (one [P=0.017] and 24 hours [P=0.007] post-session). In the frequency domain, we found a significant difference in high frequency (HF) (ms2) (parasympathetic component) (one hour [P=0.048] post-session). The low frequency (LF)/HF ratio (sympathetic and parasympathetic components with a predominance of the sympathetic component) reached statistical significance only 24 hours (P=0.018) post-session. Additionally, the largest effect size was observed only for the LF/HF ratio at one (d=-0.8) and 24 hours (d=-1.3) after one AES. Conclusion: The practice of (acute) aerobic exercise improved autonomic cardiac control in patients undergoing CABG.
Subject(s)
Humans , Male , Female , Middle Aged , Aged , Autonomic Nervous System/physiopathology , Exercise/physiology , Coronary Artery Bypass/rehabilitation , Exercise Therapy/methods , Cardiac Rehabilitation/methods , Heart Rate/physiology , Reference Values , Time Factors , Body Mass Index , Reproducibility of Results , Analysis of Variance , Treatment Outcome , Supine Position/physiology , Statistics, Nonparametric , ElectrocardiographyABSTRACT
ABSTRACT Purpose: Obesity is accepted as a risk factor for postoperative visual loss due to possible perioperative elevations in intraocular pressure. This study investigated whether intraocular pressure changes differed according to the body mass index of patients undergoing laparoscopic cholecystectomy. Methods: Thirty obese and 30 non-obese patients (body mass index cutoff point, 30 kg/m2) undergoing laparoscopic cholecystectomy were enrolled. Intraocular pressure was measured at baseline (T1), after induction of anesthesia (T2), 5 min after initiation of mechanical ventilation (T3), 5 min after pneumoperitoneum inflation (T4), 5 min after the patient was placed in the head-up position (T5), 5 min after deflation with the patient in the supine position (T6), and 5 min after extubation with the patient in the 30 degrees upright position (T7). Results: The mean intraocular pressure values of the obese and non-obese groups were similar at T1 (16.60 ± 2.93 and 16.87 ± 2.85 mmHg respectively). In both groups, intraocular pressure decreased following initiation of anesthesia (T2) (p<0.001, T2 vs T1). Intraocular pressure values at T7 were significantly higher than those at T1 in the obese (20.38 ± 4.11 mmHg, p<0.001) and non-obese (20.93 ± 4.37 mmHg, p<0.01) groups. There were no significant differences between intraocular pressure values of obese and non-obese patients at any time point. Conclusions: Obesity is not correlated with intraocular pressure during short laparoscopic surgeries with the patient in the head-up position.
RESUMO Objetivo: A obesidade é aceita como um fator de risco para a perda visual pós-operatória devido a possíveis elevações perioperatórias da pressão intraocular. Este estudo investigou se as alterações na pressão intraocular diferem de acordo com o índice de massa corporal dos pacientes submetidos à colecistectomia laparoscópica. Métodos: Trinta pacientes obesos e 30 não-obesos (limiar de índice de massa corporal de 30 kg/m2), submetidos à colecistectomia laparoscópica foram incluídos. A pressão intraocular foi medida no início do estudo (T1), após a indução anestésica (T2), 5 min após o início da ventilação mecânica (T3), 5 min após a insuflação do pneumoperitôneo (T4), 5 min após o posicionamento vertical da cabeça (T5), 5 min após a deflação na posição em decúbito dorsal (T6) e 5 min após a extubação com o paciente na posição vertical de 30 graus (T7). Resultados: Os valores médios da pressão intraocular dos grupos obeso e não obeso foram semelhantes no T1 (16,60 ± 2,93 e 16,87 ± 2,85 mmHg, respectivamente). Em ambos os grupos, a pressão intraocular diminuiu após o início da anestesia (T2) (p<0,001, T2 vs T1). Os valores da pressão intraocular em T7 foram significativamente maiores do que aqueles em T1 nos grupos obesos (20,38 ± 4,11 mmHg, p<0,001) e não obesos (20,93 ± 4,37 mmHg, p<0,01). Não houve diferenças significativas entre os valores de pressão intraocular de pacientes obesos e não obesos em qualquer momento. Conclusões: A obesidade não está correlacionada com a pressão intraocular durante cirurgias laparoscópicas curtas com o paciente em posição de cabeça erguida.
Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Aged , Young Adult , Cholecystectomy, Laparoscopic/adverse effects , Intraocular Pressure/physiology , Obesity/complications , Obesity/physiopathology , Reference Values , Time Factors , Tonometry, Ocular/methods , Body Mass Index , Ocular Hypertension/etiology , Ocular Hypertension/physiopathology , Analysis of Variance , Supine Position/physiology , Statistics, Nonparametric , Patient PositioningABSTRACT
ABSTRACT Objective: To compare the effects that prone and supine positioning during high-frequency oscillatory ventilation (HFOV) have on oxygenation and lung inflammation, histological injury, and oxidative stress in a rabbit model of acute lung injury (ALI). Methods: Thirty male Norfolk white rabbits were induced to ALI by tracheal saline lavage (30 mL/kg, 38°C). The injury was induced during conventional mechanical ventilation, and ALI was considered confirmed when a PaO2/FiO2 ratio < 100 mmHg was reached. Rabbits were randomly divided into two groups: HFOV in the supine position (SP group, n = 15); and HFOV with prone positioning (PP group, n = 15). For HFOV, the mean airway pressure was initially set at 16 cmH2O. At 30, 60, and 90 min after the start of the HFOV protocol, the mean airway pressure was reduced to 14, 12, and 10 cmH2O, respectively. At 120 min, the animals were returned to or remained in the supine position for an extra 30 min. We evaluated oxygenation indices and histological lung injury scores, as well as TNF-α levels in BAL fluid and lung tissue. Results: After ALI induction, all of the animals showed significant hypoxemia, decreased respiratory system compliance, decreased oxygenation, and increased mean airway pressure in comparison with the baseline values. There were no statistically significant differences between the two groups, at any of the time points evaluated, in terms of the PaO2 or oxygenation index. However, TNF-α levels in BAL fluid were significantly lower in the PP group than in the SP group, as were histological lung injury scores. Conclusions: Prone positioning appears to attenuate inflammatory and histological lung injury during HFOV in rabbits with ALI.
RESUMO Objetivo: Comparar os efeitos das posições prona e supina durante ventilação oscilatória de alta frequência (VOAF) sobre oxigenação e inflamação pulmonar, lesão histológica e estresse oxidativo em um modelo de lesão pulmonar aguda (LPA) em coelhos. Métodos: Trinta coelhos Norfolk machos brancos foram submetidos à LPA por meio de lavagem traqueal com salina (30 ml/kg, 38°C). A lesão foi induzida durante a ventilação mecânica convencional, e a LPA foi considerada confirmada na presença de relação PaO2/FiO2 < 100 mmHg. Os coelhos foram aleatoriamente divididos em dois grupos: VOAF em posição supina (grupo PS, n = 15); e VOAF em posição prona (grupo PP, n = 15). Para a VOAF, a pressão média das vias aéreas foi inicialmente estabelecida em 16 cmH2O. No 30º, 60º e 90º min após o início do protocolo de VOAF, a pressão média das vias aéreas foi reduzida para 14, 12 e 10 cmH2O, respectivamente. No 120º min, os animais foram recolocados ou permaneceram na posição supina por mais 30 min. Foram avaliados os índices de oxigenação e escores histológicos de lesão pulmonar, bem como os níveis de TNF-α em lavado broncoalveolar e tecido pulmonar. Resultados: Após a indução da LPA, todos os animais apresentaram hipoxemia significativa, diminuição da complacência do sistema respiratório, diminuição da oxigenação e aumento da pressão média das vias aéreas em comparação aos valores basais. Não houve diferenças estatisticamente significativas entre os dois grupos, em nenhum dos momentos avaliados, quanto a PaO2 e índice de oxigenação. Entretanto, os níveis de TNF-α no lavado broncoalveolar foram significativamente menores no grupo PP que no grupo PS, assim como os escores histológicos de lesão pulmonar. Conclusões: A posição prona parece atenuar a lesão pulmonar inflamatória e histológica durante a VOAF em coelhos com LPA.
Subject(s)
Humans , Animals , Male , Rats , High-Frequency Ventilation/methods , Supine Position/physiology , Prone Position/physiology , Acute Lung Injury/prevention & control , Oxygen/metabolism , Reference Values , Time Factors , Bronchoalveolar Lavage Fluid/chemistry , High-Frequency Ventilation/adverse effects , Lipid Peroxidation , Prospective Studies , Reproducibility of Results , Tumor Necrosis Factor-alpha/analysis , Oxidative Stress , Models, Animal , Acute Lung Injury/pathologyABSTRACT
OBJECTIVE: The reliability of heart rate variability (HRV) analysis is not yet fully understood, especially considering different body positions and the mathematical influence of heart rate. The aim of this study was to evaluate the reliability of HRV in supine and standing positions, with and without mathematical adjustment of HRV by the average R-R interval (iRR). METHODS: We evaluated 37 young males (23.1±4 years; 25.1±3 kg/m2). A 5-min segment of the iRR was collected in the supine and standing positions on three occasions separated by 48-hour intervals. Absolute and relative reliability of temporal and spectral indices were assessed by the coefficient of variation (CV) and the intraclass correlation coefficient (ICC), respectively. RESULTS: We did not observe differences in HRV indices in the three occasions in the supine or standing position (p>0.05). Moderate to good reproducibility was observed for temporal and spectral indices of HRV in the supine position (ICC: 0.65-0.89; CV: 0.9-19.8). In the orthostatic position, low to good reproducibility was observed (ICC: 0.35-0.89; CV: 1.1-34.8), with higher ICCs for temporal indices. After mathematical adjustment, only a small modification in HRV reliability was observed in both positions. CONCLUSIONS: In young adult males, the mathematical adjustment of HRV by the average iRR led to a nonsignificant effect on HRV reliability. Additionally, HRV reliability is dependent on body position and the index analyzed. Promising measures in both supine and standing positions include r-MSSD and the HF band (parasympathetic indices).
Subject(s)
Humans , Male , Adult , Young Adult , Supine Position/physiology , Standing Position , Heart Rate/physiology , Reference Values , Body Mass Index , Reproducibility of Results , Statistics, Nonparametric , Models, TheoreticalABSTRACT
Abstract Background: The prevalence of orthostatic hypotension (OH) increases with age and is associated with changes in autonomic regulation of blood pressure (BP) and heart rate (HR). Objective: to assess HR and HR variability (HRV) in elderly subjects with OH and determine OH predictors. Methods: a total of 105 patients aged ≥ 60 years, 39 with OH (case group) and 66 without OH (control group) (age-matched) were studied. Patients underwent clinical assessment, electrocardiogram, biochemistry tests and Holter monitoring for spectral analysis of HRV (Fourier transform) in the supine and orthostatism positions to identify low frequency (LF) and high frequency (HF) components, as well as the LF/HF ratio. Results: median age was 73.0 years, 64 patients were women. In all participants, there was a reduction in HF (133.0 versus 76.0 ms2, p = 0.001) and increase in LF/HF (1.6 vs 2.1; p < 0.001) and no change in LF (233.0 versus 218.0 ms2, p = 0.080). Between-group comparisons revealed significant differences in the median values of HR in the supine position (62.0 vs. 69.0 bpm, p = 0.001) and LF in the supine position (157.0 in case group vs. 275.0 ms2 in the control group, p = 0.014). Spearman's correlation coefficient of 0.27 was found between the groups. Multivariate analysis revealed that HR in the supine position was an independent variable for OH (p = 0.001- 95%CI = -0.022 and -0.006). Using the operating characteristic curve, the best cutoff point was 61 bpm, with a sensitivity of 77.3% and specificity of 51.3%, positive predictive value of 61.3%, and negative predictive value 69.3%. Odds ratio was 3.23 for OH in patients with a HR lower than 61 bpm. Conclusions: lower LF and HR in the supine position were found in patients with OH, regardless of age and gender. The independent predictor for OH was HR in the supine position, with an odds ratio of 3.23 for values lower than 61 bpm.
Resumo Fundamento: A prevalência de hipotensão ortostática (HO) aumenta com a idade e está relacionada a alterações da regulação autonômica da pressão arterial (PA) e da frequência cardíaca (FC). Objetivos: Avaliar a FC e variabilidade da FC (VFC) em idosos com HO e verificar os preditores de HO. Métodos: foram avaliados 105 pacientes, com idade ≥ 60 anos, 39 com HO (grupo caso) e 66 sem HO (grupo controle), pareados por idade. Foram submetidos à avaliação clínica, eletrocardiograma, exames de bioquímica e monitoramento pelo Holter para análise espectral da VFC (transformação de Fourier), na posição supina e em ortostatismo, para detectar os componentes de baixa frequência (LF), de alta frequência (HF) e sua relação LF/HF. Resultados: A mediana de idade foi de 73,0 anos, 64 dos pacientes eram mulheres. Em toda a população, com a mudança de posição, houve redução do HF (133,0 versus 76,0 ms2, p = 0,001) e aumento da relação LF/HF (1,6vs2,1; p < 0,001), sem alteração quanto à mediana do componente LF (233,0 versus 218,0 ms2, p = 0,080). Quando comparado o grupo caso ao grupo controle, houve diferença quanto às medianas da FC nas posições supina (62,0 vs 69,0 bpm, p = 0,001) e do componente LF na posição supina (157,0 no grupo caso vs 275,0 ms2 no grupo controle, p = 0,014). Quanto ao gênero, o coeficiente de Spearman foi de 0,27 entre os grupos. Pela análise multivariada, a FC na posição supina foi a variável independente para a ocorrência de HO (p = 0,001- IC95% = -0,022 e -0,006). Pela curva de operação característica, o melhor ponto de corte para FC foi de 61 bpm, com sensibilidade de 77,3%, especificidade de 51,3%, valor preditivo positivo de 61,3%, e o valor preditivo negativo de 69,3%. A razão de chance foi de 3,23 para HO entre os pacientes com FC < 61 bpm. Conclusões: Houve menor valor do LF e da FC na posição supina entre os pacientes com HO, sem influência da idade e do gênero. O preditor independente para HO foi a FC na posição supina, a qual apresentou uma razão de chance de 3,23 se inferior a 61 bpm.
Subject(s)
Humans , Male , Female , Aged , Heart Rate/physiology , Hypotension, Orthostatic/physiopathology , Reference Values , Time Factors , Blood Pressure/physiology , Epidemiologic Methods , Age Factors , Supine Position/physiology , Electrocardiography , Patient Positioning , Heart Rate Determination/methodsABSTRACT
Abstract Background: Cardioinhibitory vasovagal response is uncommon during the tilt test (TT). Heart rate variability (HRV) by use of spectral analysis can distinguish patients with that response. Objective: To compare the HRV in patients with cardioinhibitory vasovagal syncope (case group - G1) with that in patients without syncope and with negative response to TT (control group - G2). Methods: 64 patients were evaluated (mean age, 36.2 years; 35 men) and submitted to TT at 70 degrees, under digital Holter monitoring. The groups were paired for age and sex (G1, 40 patients; G2, 24). Results: In G1, 21 patients had a type 2A response and 19 had type 2B, with mean TT duration of 20.4 minutes. There was a greater low frequency (LF) component (11,6 versus 4,5 ms2, p=0.001) and a lower low/high frequency ratio in the supine position (3,9 versus 4,5 ms2, p=0.008) in G1, with no difference during TT between the groups. Applying the receiver operating characteristic curve for cardioinhibitory response, the area under the curve was 0.74 for the LF component in the supine position (p = 0.001). The following were observed for the cutoff point of 0.35 ms(2) for the LF component: sensitivity, 97.4%; specificity, 83.3%; positive predictive value, 85.3%; negative predictive value, 96.9%; and positive likelihood ratio, 5.8. Conclusion: HRV in the supine position allowed identifying patients with syncope and cardioinhibitory response with a high negative predictive value and likelihood ratio of 5.8.
Resumo Fundamento: A resposta cardioinibitória vasovagal ao teste de inclinação (TI) é pouco frequente. A variabilidade da frequência cardíaca (VFC) por meio da análise espectral pode discernir os pacientes (pts) com aquela resposta. Objetivo: Avaliar a VFC em pts com síncope vasovagal cardioinibitória (grupo caso - G1), comparando-a com a VFC de pts sem síncope e com resposta negativa ao TI (grupo controle - G2). Métodos: foram avaliados 64 pts, média de idade 36,2 anos, 35 homens, submetidos ao TI a 70º, sob monitoramento pelo Holter digital. Os grupos foram pareados por idade e sexo, sendo 40 pts do G1 e 24 do G2. Resultados: No G1, 21 pts apresentaram resposta tipo 2A e 19, tipo 2B, com média do TI de 20,4 min. Houve maior valor do componente de baixa frequência (BF) (11,6 versus 4,5 ms2, p=0,001) e menor relação baixa/alta frequência na posição supina (3,9 versus 4,5 ms2, p=0,008) no G1, sem diferença durante o TI. Aplicando-se a curva de operação característica para resposta cardioinibitória, foi obtida a área abaixo da curva de 0,74 para o componente BF na posição supina (p=0,001). Para o ponto de corte de 0,35 ms2 para BF observaram-se: sensibilidade, 97,4%; especificidade, 83,3%; valor preditivo positivo, 85,3%; valor preditivo negativo, 96,9%; e razão de probabilidade positiva, 5,8. Conclusão: A VFC na posição supina permitiu identificar os pts com síncope e com resposta cardioinibitória, com um alto valor preditivo negativo e uma razão de probabilidade de 5,8.
Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Aged , Young Adult , Tilt-Table Test/methods , Syncope, Vasovagal/physiopathology , Heart Rate/physiology , Reference Values , Time Factors , Blood Pressure/physiology , Prospective Studies , ROC Curve , Electrocardiography, Ambulatory , Supine Position/physiology , Statistics, Nonparametric , Electrocardiography/methodsABSTRACT
Abstract Background: Orthostatic intolerance patients' pathophysiological mechanism is still obscure, contributing to the difficulty in their clinical management. Objective: To investigate hemodynamic changes during tilt test in individuals with orthostatic intolerance symptoms, including syncope or near syncope. Methods: Sixty-one patients who underwent tilt test at - 70° in the phase without vasodilators were divided into two groups. For data analysis, only the first 20 minutes of tilting were considered. Group I was made up of 33 patients who had an increase of total peripheral vascular resistance (TPVR) during orthostatic position; and Group II was made up of 28 patients with a decrease in TPVR (characterizing insufficient peripheral vascular resistance). The control group consisted of 24 healthy asymptomatic individuals. Hemodynamic parameters were obtained by a non-invasive hemodynamic monitor in three different moments (supine position, tilt 10' and tilt 20') adjusted for age. Results: In the supine position, systolic volume (SV) was significantly reduced in both Group II and I in comparison to the control group, respectively (66.4 ±14.9 ml vs. 81.8±14.8 ml vs. 101.5±24.2 ml; p<0.05). TPVR, however, was higher in Group II in comparison to Group I and controls, respectively (1750.5± 442 dyne.s/cm5 vs.1424±404 dyne.s/cm5 vs. 974.4±230 dyne.s/cm5; p<0.05). In the orthostatic position, at 10', there was repetition of findings, with lower absolute values of SV compared to controls (64.1±14.0 ml vs 65.5±11.3 ml vs 82.8±15.6 ml; p<0.05). TPVR, on the other hand, showed a relative drop in Group II, in comparison to Group I. Conclusion: Reduced SV was consistently observed in the groups of patients with orthostatic intolerance in comparison to the control group. Two different responses to tilt test were observed: one group with elevated TPVR and another with a relative drop in TPVR, possibly suggesting a more severe failure of compensation mechanisms.
Resumo Fundamento: O mecanismo fisiopatológico de pacientes com intolerância ortostática ainda é obscuro, contribuindo para a dificuldade no manejo clínicos desses pacientes. Objetivo: Investigar as alterações hemodinâmicas durante teste de inclinação (tilt teste) em indivíduos com sintomas de intolerância ortostática, incluindo síncope ou pré-síncope. Métodos: Sessenta e um pacientes, com tilt teste a 70º negativo na fase livre de vasodilatador, foram divididos em dois grupos. Para análise dos dados foram considerados apenas os primeiros 20 minutos de inclinação. Grupo I (33 pacientes) que tiveram elevação da resistência vascular periférica total (RVPT) durante posição ortostática e Grupo II (28 pacientes) com queda da RVPT (caracterizando insuficiência de resistência vascular periférica). O grupo controle consistia de indivíduos saudáveis e assintomáticos (24 indivíduos). Os parâmetros hemodinâmicos foram obtidos por um monitor hemodinâmico não invasivo em 3 momentos distintos (posição supina, tilt 10' e tilt 20'), ajustados para idade. Resultados: Na posição supina, o volume sistólico (VS) foi significantemente reduzido tanto no Grupo II quanto no I, quando comparado ao do Grupo controle, respectivamente (66,4 ±14,9 ml vs. 81,8±14,8 ml vs. 101,5±24,2 ml; p<0,05.) A RVPT, no entanto, foi mais elevada no Grupo II, quando comparada a do Grupo I e controles, respectivamente (1750,5± 442 dyne.s/cm5 vs.1424±404 dyne.s/cm5 vs. 974,4±230 dyne.s/cm5; p<0,05). Na posição ortostática, aos 10', houve repetição dos achados, com valores absolutos inferiores de VS Comparado aos controles (64,1±14,0 ml vs 65,5±11,3 ml vs 82,8±15,6 ml; p<0,05). A RVPT, todavia, apresentou queda relativa no Grupo II comparado ao I. Conclusão: Volume sistólico reduzido foi consistentemente observado nos grupos de pacientes com intolerância ortostática, quando comparado ao grupo controle. Foram observadas duas respostas distintas ao teste de inclinação: um grupo com elevação de RVPT e outro com queda relativa desta, indicando, possivelmente, falência mais acentuada dos mecanismos de compensação.
Subject(s)
Humans , Adolescent , Adult , Middle Aged , Aged , Aged, 80 and over , Young Adult , Blood Pressure/physiology , Tilt-Table Test/methods , Orthostatic Intolerance/physiopathology , Hemodynamics/physiology , Reference Values , Syncope/physiopathology , Systole/physiology , Time Factors , Case-Control Studies , Anthropometry , Retrospective Studies , Supine Position/physiologyABSTRACT
OBJECTIVES: While respiratory distress is accepted as the only indication for diaphragmatic plication surgery, sleep disorders have been underestimated. In this study, we aimed to detect the sleep disorders that accompany diaphragm pathologies. Specifically, the association of obstructive sleep apnea syndrome with diaphragm eventration and diaphragm paralysis was evaluated. METHODS: This study was performed in Süreyyapasa Chest Diseases and Thoracic Surgery Training and Research Hospital between 2014-2016. All patients had symptoms of obstructive sleep apnea (snoring and/or cessation of breath during sleep and/or daytime sleepiness) and underwent diaphragmatic plication via video-assisted mini-thoracotomy. Additionally, all patients underwent pre- and postoperative full-night polysomnography. Pre- and postoperative clinical findings, polysomnography results, Epworth sleepiness scale scores and pulmonary function test results were compared. RESULTS: Twelve patients (7 males) with a mean age of 48 (range, 27-60) years and a mean body mass index of 25 (range, 20-30) kg/m2 were included in the study. Preoperative polysomnography showed obstructive sleep apnea syndrome in 9 of the 12 patients (75%), while 3 of the patients (25%) were regarded as normal. Postoperatively, patient complaints, apnea hypopnea indices, Epworth sleepiness scale scores and pulmonary function test results all demonstrated remarkable improvement. CONCLUSION: All patients suffering from diaphragm pathologies with symptoms should undergo polysomnography, and patients diagnosed with obstructive sleep apnea syndrome should be operated on. In this way, long-term comorbidities of sleep disorders may be prevented.
Subject(s)
Humans , Male , Female , Adult , Middle Aged , Diaphragmatic Eventration/physiopathology , Diaphragm/physiopathology , Polysomnography/methods , Respiratory Paralysis/physiopathology , Sleep Apnea, Obstructive/physiopathology , Sleep Wake Disorders/physiopathology , Diaphragmatic Eventration/diagnosis , Forced Expiratory Volume/physiology , Postoperative Period , Preoperative Period , Reference Values , Reproducibility of Results , Respiratory Paralysis/diagnosis , Severity of Illness Index , Sleep Apnea, Obstructive/diagnosis , Sleep Apnea, Obstructive/surgery , Sleep Wake Disorders/diagnosis , Statistics, Nonparametric , Supine Position/physiology , Vital Capacity/physiologyABSTRACT
Benign paroxysmal positional vertigo (BPPV), the most frequent cause of vertigo is associated with high morbidity in the elderly population. The most common form is linked to debris in the posterior semicircular canal. However, there has been an increasing number of reported BPPV cases involving the horizontal canals. The purpose of this article is to highlight the clinical features, diagnosis, and treatment in 37 patients with horizontal canal BPPV; twenty-six with geotropic nystagmus, and eleven with the apogeotropic form. Treatment consisted of the Gufoni manoeuver in eighteen patients (48.6%), the barbecue 360° maneuver in twelve patients (32.4%), both manoeuvers in four patients (10.8%), both manoeuvers plus head shaking in one patient (2.7%), and the Gufoni maneuver plus head shaking in two patients. Cupulolithiasis patients were asked to sleep in a forced prolonged position. We obtained a complete resolution of vertigo and nystagmus in 30 patients (81.0%) on the initial visit.
Vertigem posicional paroxística benigna (VPPB) é a causa mais frequente de vertigem e promove alta morbidade na população idosa. A forma mais comum está relacionada com otoconias no canal semicircular posterior. Entretanto, nos últimos anos identifica-se cada vez mais casos de VPPB dos canais horizontais. Os principais objetivos deste artigo são destacar as características clínicas, diagnóstico e tratamentos aplicados em 37 pacientes com VPPB do canal horizontal; vinte e seis com nistagmo geotrópico, e onze com nistagmo apogeotrópico. O tratamento consistiu na manobra de Gufoni em dezoito pacientes (48,6%) manobra do churrasco 360° em doze pacientes (32,4%) ambas as manobras em quatro pacientes (10,8%) ambas as manobras mais a manobra de sacudir a cabeça (MSC) em um paciente (2,7%), e manobra de Gufoni mais MSC em dois pacientes (2,7%). Pacientes com cupulolitíase dormiram uma noite na posição forçada prolongada. Em 30 pacientes (81,0%) o sucesso terapêutico ocorreu na primeira consulta.
Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Benign Paroxysmal Positional Vertigo/diagnosis , Benign Paroxysmal Positional Vertigo/therapy , Exercise Therapy/methods , Patient Positioning/methods , Benign Paroxysmal Positional Vertigo/physiopathology , Head Movements/physiology , Nystagmus, Pathologic/physiopathology , Nystagmus, Pathologic/therapy , Semicircular Canals/physiopathology , Supine Position/physiology , Time Factors , Treatment OutcomeABSTRACT
PURPOSE: To determine effectiveness of Valsalva maneuver and standing position on scrotal color Doppler ultrasound (CDU) for the varicocele diagnosis. MATERIALS AND METHODS: We reviewed the physical examination and CDU finding in 87 patients who visited National Police Hospital from January 2011 to April 2014. Diameters of pampiniform plexus were measured bilaterally during resting and Valsalva maneuver in the supine position and standing position. We calculated the ratio of mean of maximal vein diameter (mMVD) during resting and Valsalva maneuver (resting-Valsalva ratio) and compared in the both position. RESULTS: In the resting and supine position, mMVD of varicocele testis units were 1.8 mm, 2.1 mm, 2.6 mm (grades I, II, III, respectively), and that of normal testis units (NTU) 1.2 mm. During Valsalva maneuver in the supine position, mMVD were 3.0 mm, 3.4 mm, 4.2 mm (grades I, II, III) vs 1.8 mm (NTU) (p=0.007, p<0.001, p<0.001, respectively). Average of resting-Valsalva ratio in the supine position were 0.69, 0.74, 0.74 (grades I, II, III) and 0.67 (NTU). Whereas in the resting and standing position, mMVD were 2.8 mm, 3.3 mm, 3.8 mm (grades I, II, III) and 1.8 mm (NTU) (p=0.002, p<0.001, p<0.001). During Valsalva maneuver in the standing position, mMVD were 5.0 mm, 5.8 mm, 6.6 mm (grades I, II, III) and 2.5 mm (NTU) (p=0.002, p<0.001, p<0.001). And average resting-Valsalva ratio were 0.76, 0.90, 0.71 (grades I, II, III) and 0.26 (NTU), which showed significant differences from all grades (p<0.001, p<0.001, p<0.001). CONCLUSIONS: It is suggested that the standing position and Valsalva maneuver during CDU could improve diagnostic ability for varicocele. Resting-Valsalva ratio in the standing position could be a new diagnostic index for varicocele diagnosis using CDU.
Subject(s)
Adult , Aged , Humans , Male , Middle Aged , Young Adult , Patient Positioning/methods , Physical Examination/methods , Posture/physiology , Scrotum/diagnostic imaging , Supine Position/physiology , Ultrasonography, Doppler, Color/methods , Valsalva Maneuver , Varicocele/diagnostic imaging , Veins/diagnostic imagingABSTRACT
Background: Early mobilization in intensive care units (ICU) provides respiratory, neurological and cardiovascular benefits in hospitalized patients. However, the orthostatic effects of changing from a supine to a sitting position may interfere with cerebral hemodynamics of patients with aneurysmal subarachnoid hemorrhage (aSAH). Aim: To describe the changes in mean cerebral blood flow velocity (MCBFV) in supine and sitting position, in adult patients with aSAH, with asymptomatic vasospasm (AVS) or without vasospasm (VS) at a neurosurgical ICU. Material and Methods: Descriptive case series study in 21 patients with aSAH, both with and without VS. They were positioned in a supine 30° position and then seated at the edge of bed for six minutes. MCBFV was measured by transcranial Doppler (TCD), and hemodynamic variables in both positions were registered. After this basal assessment and for 21 days after the episode of SAH, patients were seated once a day and signs of VS were recorded. Results: No significant changes in MCBFV or hemodynamic variables were detected during position changes, except for an increase in heart rate in the sitting position. No patient with AVS at the onset, had symptomatic VS during the 21 days of follow up when patients were seated. Among patients with a normal MCBFV at baseline, five patients (24%) had VS at a mean of three days after the first time that they were seated on the edge of bed. Conclusions: Sitting patients at the edge of the bed is a safe mobilization alternative for patients who suffered aSAH who did not have VS or had AVS.
Subject(s)
Adult , Female , Humans , Male , Cerebrovascular Circulation/physiology , Patient Positioning/methods , Subarachnoid Hemorrhage/physiopathology , Supine Position/physiology , Vasospasm, Intracranial/physiopathology , Blood Flow Velocity/physiology , Patient Positioning/adverse effects , Subarachnoid Hemorrhage/complications , Subarachnoid Hemorrhage , Ultrasonography, Doppler, Transcranial , Vasospasm, Intracranial/etiology , Vasospasm, IntracranialABSTRACT
FUNDAMENTO: Diversos mecanismos podem estar envolvidos no desencadeamento da síncope em pacientes com cardiomiopatia hipertrófica (CMH), incluindo colapsos hemodinâmicos que podem estar relacionados a um desequilíbrio autonômico. OBJETIVO: Avaliar e comparar a função autonômica de pacientes que apresentam CMH com síncope inexplicada (SI) com os que não apresentam síncope. MÉTODOS: Trinta e sete pacientes foram incluídos, sendo 16 com SI e 21 sem síncope. Sua função autonômica foi avaliada por sensibilidade barorreflexa (SB) espontânea e induzida por fenilefrina, pela variabilidade da frequência cardíaca (VFC) no domínio do tempo durante o Holter de 24 horas e no domínio da frequência (análise espectral), ambos em decúbito dorsal e no teste de inclinação (TI) a 70º. RESULTADOS: A SB espontânea mostrou-se semelhante em ambos os grupos (16,46 ± 12,99 vs. 18,31 ± 9,88 ms/mmHg, p = 0,464), assim como a SB induzida por fenilefrina (18,33 ± 9,31 vs. 15,83 ± 15,48 ms/mmHg, p = 0,521). Não foram observadas diferenças no SDNN (137,69 ± 36,62 vs . 145,95 ± 38,07 ms, p = 0,389). O grupo com síncope apresentou um RMSSD significativamente menor (24,88 ± 10,03 vs. 35,58 ± 16,43 ms, p = 0,042) e tendência a menor pNN50 (4,51 ± 3,78 vs . 8,83 ± 7,98%, p =0,085) e a menores valores do componente de alta frequência da análise espectral da VFC em repouso (637,59 ± 1.295,53 vs. 782,65 ± 1.264,14 ms2 , p = 0,075). Nenhuma diferença significativa foi observada em resposta ao TI (p = 0,053). A sensibilidade, especificidade e acurácia do TI na identificação da etiologia da SI em pacientes com CMH foram 6%, 66% e 40%, respectivamente. CONCLUSÃO: Observou-se tônus parassimpático mais baixo em pacientes com CMH e SI, mas a relevância clínica deste achado ainda não está clara. O TI não é uma ferramenta vantajosa para avaliar a origem da síncope em tais doentes, principalmente por causa da sua baixa especificidade.
BACKGROUND: Several mechanisms may be involved in the trigger of syncope in patients with hypertrophic cardiomyopathy (HCM), including hemodynamic collapses that might be related to an autonomic imbalance. OBJECTIVE: To evaluate and compare the autonomic function of patients presenting HCM with unexplained syncope (US) to those without syncope. METHODS: Thirty-seven patients were included, 16 with US and 21 without syncope. Their autonomic function was assessed by spontaneous and phenylephrine induced baroreflex sensitivity (BRS), by heart rate variability (HRV) in time domain during 24-hour Holter and in frequency domain (spectral analysis), both in supine position and at 70º head-up tilt (HUT). RESULTS: The spontaneous BRS was similar in both groups (16,46 ± 12,99 vs. 18,31 ± 9,88 ms/mmHg, p = 0,464), as was phenylephrine-induced BRS (18,33 ± 9,31 vs. 15,83 ± 15,48 ms/mmHg, p = 0,521). No differences were observed in SDNN (137,69 ± 36,62 vs . 145,95 ± 38,07 ms, p=0,389). The group presenting syncope had a significantly lower RMSSD (24,88±10,03 vs. 35,58 ± 16,43 ms, p = 0,042) and a tendency to lower pNN50 (4,51 ± 3,78 vs . 8,83 ± 7,98%, p =0,085) and lower values of the high frequency component of HRV spectral analysis at rest (637,59±1.295,53 vs. 782,65±1.264,14ms2, p=0,075). No significant difference was observed in response to HUT (p = 0,053). HUT sensitivity, specificity and accuracy in identifying the etiology of US in HCM patients were 6%, 66% and 40%, respectively. CONCLUSIONS: A lower parasympathetic tone was observed in HCM patients with US, but the clinical relevance of this finding remains unclear. HUT is not a valuable tool for evaluating the origin of syncope in these patients, mainly because of its poor specificity.
Subject(s)
Adult , Female , Humans , Male , Autonomic Nervous System/physiopathology , Baroreflex/physiology , Cardiomyopathy, Hypertrophic/physiopathology , Heart Rate/physiology , Syncope/physiopathology , Baroreflex/drug effects , Epidemiologic Methods , Phenylephrine/administration & dosage , Supine Position/physiology , Tilt-Table TestABSTRACT
OBJECTIVE: Obstructive sleep apnea is frequent during the acute phase of stroke, and it is associated with poorer outcomes. A well-established relationship between supine sleep and obstructive sleep apnea severity exists in non-stroke patients. This study investigated the frequency of supine sleep and positional obstructive sleep apnea in patients with ischemic or hemorrhagic stroke. METHODS: Patients who suffered their first acute stroke, either ischemic or hemorrhagic, were subjected to a full polysomnography, including the continuous monitoring of sleep positions, during the first night after symptom onset. Obstructive sleep apnea severity was measured using the apnea-hypopnea index, and the NIHSS measured stroke severity. RESULTS: We prospectively studied 66 stroke patients. The mean age was 57.6±11.5 years, and the mean body mass index was 26.5±4.9. Obstructive sleep apnea (apnea-hypopnea index >5) was present in 78.8% of patients, and the mean apnea-hypopnea index was 29.7±26.6. The majority of subjects (66.7%) spent the entire sleep time in a supine position, and positional obstructive sleep apnea was clearly present in the other 23.1% of cases. A positive correlation was observed between the NIHSS and sleep time in the supine position (r s = 0.5; p<0.001). CONCLUSIONS: Prolonged supine positioning during sleep was highly frequent after stroke, and it was related to stroke severity. Positional sleep apnea was observed in one quarter of stroke patients, which was likely underestimated during the acute phase of stroke. The adequate positioning of patients during sleep during the acute phase of stroke may decrease obstructive respiratory events, regardless of the stroke subtype.
Subject(s)
Female , Humans , Male , Middle Aged , Cerebral Hemorrhage/physiopathology , Sleep Apnea, Obstructive/diagnosis , Sleep/physiology , Stroke/physiopathology , Supine Position/physiology , Body Mass Index , Cerebral Hemorrhage/complications , Epidemiologic Methods , Polysomnography , Sleep Apnea, Obstructive/etiology , Stroke/complications , Time FactorsABSTRACT
The objective of this study was to use linear and non-linear methods to investigate cardiac autonomic modulation in healthy elderly men and women in response to a postural change from the supine to the standing position. Fourteen men (66.1 ± 3.5 years) and 10 women (65.3 ± 3.3 years) were evaluated. Beat-to-beat heart rate was recorded in the supine and standing positions. Heart rate variability was studied by spectral analysis, including both low (LFnu-cardiac sympathetic modulation (CSM) indicator) and high (HFnu-cardiac vagal modulation (CVM) indicator) frequencies in normalized units as well as the low frequency/high frequency (LF/HF) ratio. Symbolic analysis was performed using the following indexes: 0V percent (CSM indicator), 1V percent (CSM and CVM indicators), 2LV percent (predominantly CVM indicator) and 2ULV percent (CVM indicator). Shannon entropy was also calculated. Men presented higher LFnu and LF/HF ratio and lower HFnu and 1V percent symbolic index (57.56, 4.14, 40.53, 45.96, respectively) than women (24.60, 0.45, 72.47, 52.69, respectively) in the supine position. Shannon entropy was higher among men (3.53) than among women (3.33) in the standing position, and also increased according to postural change in men (3.25; 3.53). During postural change, the LFnu (24.60; 49.85) and LF/HF ratio (0.45; 1.72) increased, with a concomitant decrease in HFnu (72.47; 47.56) and 2LV percent (14.10; 6.95) in women. Women presented increased CSM in response to postural change and had higher CVM and lower CSM than men in the supine position. In conclusion, women in the age range studied presented a more appropriate response to a postural change than men, suggesting that cardiac autonomic modulation may be better preserved in women than in men.
Subject(s)
Aged , Female , Humans , Male , Middle Aged , Autonomic Nervous System/physiology , Heart Rate/physiology , Posture/physiology , Sex Factors , Electrocardiography , Models, Cardiovascular , Supine Position/physiologyABSTRACT
Contexto: O aumento do volume gástrico observado na alimentação por gavagem traz consequências ao recém-nascido pré-termo, alterando indicadores da função respiratória. Objetivo: Investigar as alterações no sistema cardiorrespiratório nas diferentes posições do corpo de recém-nascidos prematuros submetidos ao aumento do volume gástrico através da alimentação por gavagem. Métodos: Trata-se de um ensaio aleatório, tipo "crossover". Foram estudados 16 recém-nascidos de 31 a 34 semanas de idade gestacional e peso menor ou igual a 2.500 g. Foram incluídos os recém-nascidos com 7 a 10 dias de vida, alimentados via sonda orogástrica (fórmula artificial padronizada e/ou leite materno ordenhado no banco de leite do Hospital Santa Casa de Misericórdia de Franca, SP) de 3 em 3 horas, volume total de 150 mL/kg/dia, sem oxigenoterapia suplementar. Foi utilizado a cada gavagem um posicionamento diferente e elevado a 30°, tal como: lateral direito, lateral esquerdo, pronação e supinação. Foram observadas as variáveis: frequência respiratória e cardíaca, saturação de oxigênio, tiragem de intercostais, batimento de asa nasal e gemência. Estas variáveis foram coletadas de 2 em 2 minutos, a partir de 5 minutos, antecedendo a gavagem e até 5 minutos após. Resultados: O grupo estudado apresentou média de 32 semanas de idade gestacional (desvio-padrão 1,3), peso médio de 1.722 g (desvio-padrão 276,3). Em supinação e lateral esquerdo, a frequência respiratória média apresentou-se com valores mais altos e a saturação de oxigênio média apresentou os menores valores. Em lateral direito e pronação os níveis de frequência cardíaca média foram mais baixos e estáveis. Os posicionamentos lateral direito e pronação apresentaram maior ausência de tiragem intercostal, batimento de asa nasal e gemência. Conclusão: Os decúbitos lateral direito e pronação demonstraram maior repercussão positiva (menor aumento da frequência cardíaca, da frequência respiratória, menor diminuição...
Context: The increase of the gastric volume observed in the gavage feeding is likely to cause consequences to the premature newborn, modifying the respiratory indicators. Objective: To investigate the alterations in the cardiorespiratory system of premature newborns submitted to an increase of the gastric volume by gavage feeding, according to four different body positioning methods. Methods: The study is a randomized crossover trial using a sample of 16 newborns with gestational age from 31 to 34 weeks and birth weight less or equal to 2.500 g. The newborns were included in the study if they had from 7 to 10 days of life, feeding by orogastric tube, total volume of 150 mL/kg/day and absence of supplemental oxygen-therapy. A different positioning method was used at each gavage (all raised to 30º), or say, right lateral, left lateral, prone and supine positions. The following response variables were considered: respiratory and cardiac frequencies, saturation of oxygen, drawing of intercostals, beating of nasal wing and grunting. These measures were collected in intervals of 2 minutes during 5 minutes after the gavage feeding, during whole period of the gavage feeding, and during 5 minutes before the gavage feeding. Results: The mean gestational age was 32 weeks (standard deviation 1.3) and the mean weight of the newborns was 1.722 g (standard deviation 276.3). The newborns presented higher values of the mean respiratory frequency in supine and left lateral body positions. In the right lateral and prone positions, the newborns presented lower mean cardiac frequency. The mean oxygen saturation had the lowest values in the left lateral and supine positions. The right lateral and prone positions presented low frequencies of intercostals drawing, beating of nasal wing and grunting. Conclusion: Our results indicate that right lateral and prone positions have influence on the cardiorespiratory effect, where left lateral and supine are the positions...
Subject(s)
Female , Humans , Infant, Newborn , Male , Blood Pressure/physiology , Heart Rate/physiology , Infant, Premature/physiology , Posture/physiology , Respiratory Mechanics/physiology , Stomach/anatomy & histology , Cross-Over Studies , Enteral Nutrition , Organ Size/physiology , Prone Position/physiology , Respiration , Supine Position/physiologyABSTRACT
OBJETIVO: Avaliar a influência das posições prona e supina em recém-nascidos prematuros pós-síndrome do desconforto respiratório, respirando espontaneamente e em estado de sono ativo, sobre variáveis de padrão respiratório, movimento toracoabdominal e saturação periférica da hemoglobina pelo oxigênio. MÉTODOS: Estudo quase experimental. Doze prematuros com peso > 1.000 g no momento do estudo foram estudados nas duas posições, em ordem randomizada. A pletismografia respiratória por indutância foi utilizada para avaliação do padrão respiratório (volume corrente, frequência respiratória, ventilação minuto, fluxo inspiratório médio) e do movimento toracoabdominal (índice de trabalho respiratório, relação de fase inspiratória, relação de fase expiratória, relação de fase respiratória total e ângulo de fase). A oximetria de pulso registrou a saturação periférica de oxigênio. Para a análise estatística foram realizados os testes t de Student para amostras pareadas ou Wilcoxon. Foi considerado significativo p < 0,05. RESULTADOS: Foram analisados 9.167 ciclos respiratórios. Na posição prona, houve redução significativa do índice de trabalho respiratório (-0,84±0,69; p = 0,001; IC95 por cento -1,29 a -0,40), das relações de fase inspiratória (-27,36±17,55; p = 0,000; IC95 por cento -38,51 a -16,20), expiratória (-32,36±16,20; p = 0,000; IC95 por cento -42,65 a -22,06) e total (-30,20±14,76; p = 0,000; IC95 por cento -39,59 a -20,82). Não houve diferença significativa entre as posições nas demais variáveis analisadas. CONCLUSÃO: A posição prona promoveu diminuição significativa da assincronia toracoabdominal, sem influenciar o padrão respiratório e a saturação periférica de oxigênio.
OBJECTIVE: To assess the effect of prone and supine positions on breathing pattern variables, thoracoabdominal motion and peripheral oxygen saturation of hemoglobin of premature newborn infants recovering from respiratory distress syndrome, while breathing spontaneously and in rapid eye movement sleep. METHODS: This was a quasi-experimental study. Twelve preterms weighing > 1,000 g at enrollment were studied in both positions, in random order. Respiratory inductive plethysmography was used to analyze breathing pattern (tidal volume, respiratory rate, minute ventilation, mean inspiratory flow) and thoracoabdominal motion (labored breathing index, phase relation in inspiration, phase relation in expiration, phase relation in total breath and phase angle). Pulse oximetry was used to evaluate peripheral oxygen saturation. Student's t test for paired samples or the Wilcoxon test were used for statistical analysis. Significance was set at p < 0.05. RESULTS: A total of 9,167 respiratory cycles were analyzed. The prone position was associated with significant reductions in labored breathing index (-0.84±0.69; p = 0.001; 95 percentCI -1.29 to -0.40), phase relation in inspiration (-27.36±17.55; p = 0.000; 95 percentCI -38.51 to -16.20), phase relation in expiration (-32.36±16.20; p = 0.000; 95 percentCI -42.65 to -22.06) and phase relation in total breath (-30.20±14.76; p = 0.000; 95 percentCI -39.59 to -20.82). There were no significant differences between the two positions in any of the other variables analyzed. CONCLUSION: The prone position resulted in a significant reduction in thoracoabdominal asynchrony, without affecting breathing pattern or peripheral oxygen saturation.
Subject(s)
Female , Humans , Infant, Newborn , Male , Abdominal Muscles/physiology , Posture/physiology , Respiratory Mechanics/physiology , Infant, Premature , Oxygen Consumption/physiology , Prone Position/physiology , Statistics, Nonparametric , Supine Position/physiologyABSTRACT
One of the nurses' roles in patient care is frequent position change in patients undergoing mechanical ventilation. Because of attaching many lines and tubes to these patients, they are in supine or lateral positions most of the time. Nurses prefer these positions due to making care simple. Many studies have shown that prone position has positive effects on oxygenation and ventilation. However, other studies have shown some negative effects. The aim of this study was to determine the effect of prone position on oxygenation in patients undergoing mechanical ventilation. In this quasi-experimental study, 36 patients were selected using simple sampling method. Data were collected using a questionnaire and oxygenation data sheet. First, patients were put in supine position. After 30 and 120 minutes, oxygenation was assessed. Then they were changed to prone position and after 30 and 120 minutes oxygenation was reassessed. Data were analyzed using paired t test, spearman, and fisher exact tests in SPSS. The results indicated that there was significant differences between prone position and the amount of spo2 and sao2 oxygenation after 30 and 120 minutes [P < 0.001]. Prone positioning was effective on oxygenation after 30 and 120 minutes; so nurse should use this position in their care