RESUMO
BACKGROUND: Surfactant deficiency is the pivotal abnormality in Neonatal and Acute Respiratory Distress Syndrome. Surfactant deactivation can produce hypoxemia, loss of lung compliance, and pulmonary edema, but its circulatory consequences are less understood. OBJECTIVE: To describe the sequential hemodynamic changes and pulmonary edema formation after surfactant deactivation in piglets. METHODS: Surfactant deactivation was induced by tracheal instillation of polysorbate 20 in 15 anesthetized and mechanically ventilated Large White piglets. The hemodynamic consequences of surfactant deactivation were assessed at 30, 120, and 240 min by transpulmonary thermodilution and traditional methods. RESULTS: Surfactant deactivation caused hypoxemia, reduced lung compliance, and progressively increased lung water content (P < 0.01). Early hypovolemia was observed, with reductions of the global end-diastolic volume and stroke volume (P < 0.05). Reduced cardiac output was observed at the end of the study (P < 0.05). Standard monitoring was unable to detect these early preload alterations. Surprisingly, the bronchoalveolar protein content was greatly increased at the end of the study compared with baseline levels (P < 0.01). This finding was inconsistent with the notion that the pulmonary edema induced by surfactant deactivation was exclusively caused by high surface tension. CONCLUSIONS: Hypovolemia develops early after surfactant deactivation, in part due to the resulting fluid shift from the intravascular compartment to the lungs.
Assuntos
Água Extravascular Pulmonar/fisiologia , Deslocamentos de Líquidos Corporais/fisiologia , Hipovolemia/fisiopatologia , Surfactantes Pulmonares , Anestesia , Animais , Gasometria , Líquido da Lavagem Broncoalveolar , Excipientes , Hemodinâmica/fisiologia , Hipovolemia/induzido quimicamente , Complacência Pulmonar/fisiologia , Polissorbatos , Respiração com Pressão Positiva , Edema Pulmonar/patologia , Respiração Artificial , Suínos , TermodiluiçãoRESUMO
BACKGROUND: Currently, 13-cis-retinoic acid (13-cis-RA) is the most effective therapy for acne. Isotretinoin, a first-generation synthetic 13-cis-RA compound, is associated with numerous adverse effects. To investigate the cardiac effects of 13-cis-RA, acne patients receiving 13-cis-RA were studied. METHODS: Twenty male patients with acne were enrolled in the study. Patients were treated with a dose of 0.5 mg/kg/d of isotretinoin. All participants were assessed prior to treatment and after 10 weeks of therapy with Doppler-echocardiogram. RESULTS: Patients showed reductions in right atrium vertical diameter, left atrium longitudinal diameter, left atrium volume and left ventricular diastolic diameter over the course of treatment. Significant increases in interventricular septum diastolic thickness, posterior wall diastolic thickness, relative wall relative thickness and left ventricle (LV) mass were observed. The LV mass index showed an increase in ventricular mass and a decrease in the cavity size. Examining LV systolic function, a decrease was observed for the cardiac index. CONCLUSION: In this study, 10 weeks of 13-cis-RA therapy at a dose of 0.5 mg/kg/d was found to promote concentric-type heart remodeling due to the occurrence of two associated events: heart hypertrophy and hypovolemia.
Assuntos
Acne Vulgar/tratamento farmacológico , Acne Vulgar/epidemiologia , Isotretinoína/efeitos adversos , Remodelação Ventricular/efeitos dos fármacos , Acne Vulgar/fisiopatologia , Adolescente , Humanos , Hipertrofia Ventricular Esquerda/induzido quimicamente , Hipertrofia Ventricular Esquerda/epidemiologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Hipovolemia/induzido quimicamente , Hipovolemia/epidemiologia , Hipovolemia/fisiopatologia , Masculino , Estudos Prospectivos , Resultado do Tratamento , Remodelação Ventricular/fisiologia , Adulto JovemRESUMO
O objetivo deste estudo foi comparar os efeitos da expansão volêmica produzida pelo hidroxietilamido 130/0,4 (HES 130/0,4) ou pelo sangue em gatas com hipovolemia induzida. Foram utilizadas 12 gatas adultas, sem raça definida (SRD), com peso médio de 2,85±0,28kg e hígidas. Os animais foram induzidos à anestesia geral com isofluorano a 5V por cento, intubados e conectados a um sistema sem reinalação de gases. Após a instrumentação, os animais foram mantidos sob anestesia com isoflurano em 1,3V por cento e mantidos em ventilação mecânica, ciclada a pressão. Em seguida, foi induzida a hipovolemia por meio da retirada de 30ml kg-1 de sangue da artéria femoral. Após 60 minutos da estabilização do paciente, os tratamentos foram iniciados. No grupo hidroxietilamido (GH, n=06), os animais receberam, como reposição volêmica, o hidroxietilamido 130/0,4 no mesmo volume de sangue retirado e, no grupo sangue (GS, n=06), os animais receberam o próprio sangue retirado, sendo considerado grupo controle. A pressão arterial sistólica, a diastólica e a média e a pressão venosa central aumentaram após a reposição volêmica em ambos os grupos. Observou-se, para o GH, aumento da PaCO2 no T15, no T30 e no T60. Houve redução do pH no T30 e no T45 e de íons Na+ no T90 para GH. A restauração das pressões arteriais com a administração de HES 130/0,4 foi similar ao grupo controle. A reposição volêmica com HES 130/0,4 produz aumento acentuado da PVC; e o uso do HES 130/0,4 em gatas submetidas à hipovolemia não produziu alterações clinicamente significativas no equilíbrio ácido-básico.
The aim of this study was to compare the volemic expansion effects produced by hydroxyethyl starch 130/0.4 (HES 130/0.4) or blood, in female cats with induced hypovolemia. Twelve healthy adult female cats, crossbreed and weighing an average of 2.85±0.28kg were used. They were induced into general anesthesia with isofluorane at 5V percent, intubated and connected to a non-rebreathing system. After instrumentation, the animals were maintained under anesthesia with isofluorane at 1.3V percent and maintained on pressure cycled mechanic ventilation. Afterwards, hypovolemia was induced by withdrawal of 30ml kg-1 of blood from the femoral artery. After 60 minutes of stabilization of the patient, the treatments were initiated. In the hydroxyethyl starch group (GH, n=06) the animals received hydroxyethyl starch 130/0.4 as volemic expansion at the same volume of blood withdrawed, in the blood group (GS, n=06) the animals received their own withdrawed blood, being considered the control group. The systolic, diastolic and mean arterial pressures and central venous pressure increased after volemic expansion in both groups. An increase of PaCO2 at T15, T30 and T60 in GH was observed. In addition, there was reduction of pH at T30 and T45 and Na+ ions at T90 in GH. The arterial pressure restoration with the use of HES 130/0.4 was similar to the control group; the volemic expansion with HES 130/0,4 produces accentuated increase of CVP; the use of HES 130/0,4 in female cats submitted to hypovolemia did not produce clinically significant alterations in acid-base equilibrium.
Assuntos
Animais , Feminino , Gatos , Derivados de Hidroxietil Amido/efeitos adversos , Hipovolemia/induzido quimicamente , Hipovolemia/veterinária , Metabolismo , Sistema Cardiovascular , Substitutos do Plasma/efeitos adversos , Transfusão de Sangue Autóloga/veterináriaRESUMO
Hypokalemia (serum K+ < 3.5 mEq/1) is a potentially serious adverse effect of diuretic ingestión. We report a 27 year-old woman admitted with muscle weakness, a serum potassium of 2.0 mEq/1, metabolic alkalosis and EKG abnormalities simulating cardiac ischemia, that reverted with potassium chloride administration. She admitted high dose furosemide self-medication for edema. Glomerular filtration rate, tubular sodium reabsortion, potassium secretion, the renin-aldosterone system, total body water distribution and capillary permeability, were studied sequentially until 90 days after her admission. There was hyperactivity of the renin-aldosterone axis, reduction in extracellular and intracellular volumes, normal capillary permeability and high sodium tubular reabsorption, probably explained by a "rebound" salt retention associated with her decreased extracellular volume.
Assuntos
Adulto , Feminino , Humanos , Diuréticos/efeitos adversos , Furosemida/efeitos adversos , Hipopotassemia/induzido quimicamente , Hipovolemia/induzido quimicamente , Automedicação/efeitos adversos , Edema/tratamento farmacológico , Eletrocardiografia/efeitos dos fármacos , Cloreto de Potássio/uso terapêuticoRESUMO
Estudaram-se os efeitos de soluções salinas isotônica e hipertônica em eqüinos hipovolêmicos sobre as concentrações séricas de sódio, cloreto e potássio e freqüências cardíaca (FC) e respiratória (FR). Quinze eqüinos machos com peso entre 390 e 475kg e idades entre quatro e 18 anos foram submetidos à retirada de sangue correspondente a 2 por cento do peso corporal e distribuídos em três grupos de igual número: o grupo GSH recebeu solução hipertônica de NaCl a 7,5 por cento em glicose a 5 por cento; o GSI, solução isotônica de NaCl a 0,9 por cento; e o GC não foi tratado. Os eletrólitos séricos foram avaliados antes (T0), após a retirada de sangue (T1) e após a infusão das soluções, entre 20 e 30 minutos (T2), entre 60 e 70 minutos (T3) e entre 120 e 130 minutos (T4). Após T0, houve elevação da FC e da FR, e as concentrações séricas de Na, Cl, K permaneceram inalteradas. Após a infusão, houve melhora das variáveis clínicas em GSI e GSH, em relação ao GC. Quanto a T3 e T4, os valores de Na em T2 do GSH foram maiores, e os de Cl e de K não se alteraram. As soluções hipertônica e isotônica são seguras na correção da hipovolemia induzida e não produzem alteração eletrolítica significativa.
The effect of isotonic and hypertonic solutions on serum levels of sodium, chloride and potassium and cardiac (CR) and respiratory rates (RR) of hypovolemic horses were studied. Fifteen horses weighting from 390 to 475kg, aging from four to 18-years-old were submitted to bleeding of 2 percent of body weight and divided in three groups: 7.5 percent NaCl hypertonic saline in 5 percent glucose (GSH), 0.9 percent NaCl isotonic saline and control group (GC). Serum electrolytes were evaluated before (T0) and after bleeding (T1) and after the administration of the solutions between 20 and 30 minutes (T2), 60 and 70 minutes (T3) and 120 and 130 minutes (T4). After T0, CR and RR increased while serum sodium, chloride, potassium were not affected. After the treatment, the clinical variables improved in GSI and GSH as compared to GC. The Na levels increased in GSH at T2 being higher than T3 and T4 while chloride and potassium concentrations did not change. The hypertonic and isotonic solutions safely corrected the hypovolemia of the horses, without altering significantly the electrolyte balance.
Assuntos
Animais , Masculino , Cavalos , Hipovolemia/induzido quimicamente , Solução Salina Hipertônica/efeitos adversos , Solução Salina Hipertônica/uso terapêutico , Soluções Isotônicas/efeitos adversos , Soluções Isotônicas/uso terapêutico , Hidratação/veterinária , BiomarcadoresRESUMO
Estudaram-se os efeitos de soluções salinas isotônica e hipertônica em eqüinos hipovolêmicos sobre as concentrações séricas de sódio, cloreto e potássio e freqüências cardíaca (FC) e respiratória (FR). Quinze eqüinos machos com peso entre 390 e 475kg e idades entre quatro e 18 anos foram submetidos à retirada de sangue correspondente a 2 por cento do peso corporal e distribuídos em três grupos de igual número: o grupo GSH recebeu solução hipertônica de NaCl a 7,5 por cento em glicose a 5 por cento; o GSI, solução isotônica de NaCl a 0,9 por cento; e o GC não foi tratado. Os eletrólitos séricos foram avaliados antes (T0), após a retirada de sangue (T1) e após a infusão das soluções, entre 20 e 30 minutos (T2), entre 60 e 70 minutos (T3) e entre 120 e 130 minutos (T4). Após T0, houve elevação da FC e da FR, e as concentrações séricas de Na, Cl, K permaneceram inalteradas. Após a infusão, houve melhora das variáveis clínicas em GSI e GSH, em relação ao GC. Quanto a T3 e T4, os valores de Na em T2 do GSH foram maiores, e os de Cl e de K não se alteraram. As soluções hipertônica e isotônica são seguras na correção da hipovolemia induzida e não produzem alteração eletrolítica significativa.(AU)
The effect of isotonic and hypertonic solutions on serum levels of sodium, chloride and potassium and cardiac (CR) and respiratory rates (RR) of hypovolemic horses were studied. Fifteen horses weighting from 390 to 475kg, aging from four to 18-years-old were submitted to bleeding of 2 percent of body weight and divided in three groups: 7.5 percent NaCl hypertonic saline in 5 percent glucose (GSH), 0.9 percent NaCl isotonic saline and control group (GC). Serum electrolytes were evaluated before (T0) and after bleeding (T1) and after the administration of the solutions between 20 and 30 minutes (T2), 60 and 70 minutes (T3) and 120 and 130 minutes (T4). After T0, CR and RR increased while serum sodium, chloride, potassium were not affected. After the treatment, the clinical variables improved in GSI and GSH as compared to GC. The Na levels increased in GSH at T2 being higher than T3 and T4 while chloride and potassium concentrations did not change. The hypertonic and isotonic solutions safely corrected the hypovolemia of the horses, without altering significantly the electrolyte balance.(AU)
Assuntos
Animais , Masculino , Soluções Isotônicas/uso terapêutico , Soluções Isotônicas/efeitos adversos , Solução Salina Hipertônica/uso terapêutico , Solução Salina Hipertônica/efeitos adversos , Hipovolemia/induzido quimicamente , Cavalos , Biomarcadores , Hidratação/veterináriaRESUMO
Hypokalemia (serum K+ < 3.5 mEq/1) is a potentially serious adverse effect of diuretic ingestion. We report a 27 year-old woman admitted with muscle weakness, a serum potassium of 2.0 mEq/1, metabolic alkalosis and EKG abnormalities simulating cardiac ischemia, that reverted with potassium chloride administration. She admitted high dose furosemide self-medication for edema. Glomerular filtration rate, tubular sodium reabsorption, potassium secretion, the renin-aldosterone system, total body water distribution and capillary permeability, were studied sequentially until 90 days after her admission. There was hyperactivity of the renin-aldosterone axis, reduction in extracellular and intracellular volumes, normal capillary permeability and high sodium tubular reabsorption, probably explained by a "rebound" salt retention associated with her decreased extracellular volume.
Assuntos
Diuréticos/efeitos adversos , Furosemida/efeitos adversos , Hipopotassemia/induzido quimicamente , Hipovolemia/induzido quimicamente , Automedicação/efeitos adversos , Adulto , Edema/tratamento farmacológico , Eletrocardiografia/efeitos dos fármacos , Feminino , Humanos , Cloreto de Potássio/uso terapêuticoRESUMO
Furosemide is a potent diuretic that affects water transfer across the respiratory epithelium, which is closely related to the transepithelial potential difference (PD). Water is a critical factor that determines mucus transport; an important lung defence mechanism that removes particles and microorganisms from the respiratory system. The aim of the present study was to investigate the acute effects of furosemide and hypovolaemia on tracheal PD and mucus properties. A total of 36 male mixed-breed dogs were submitted to anaesthesia, mechanical ventilation and haemodynamic monitoring. They were randomly assigned to three groups consisting of: a control group, a furosemide (40 mg i.v.) + hypovolaemia group, and a furosemide (40 mg i.v.) + volume replacement group. Tracheal PD and mucus samples were collected at time 0, 1 and 2 h after intervention. Mucus properties were analysed by means of a magnetic microrheometer and in vitro mucociliary transportability on the frog palate. Compared to controls, furosemide decreased PD to intermediate values, and only significantly when associated with hypovolaemia (-13+/-5 and -8+/-2 mV, time 0 and 2 h, respectively). In addition to the direct effect of furosemide, these results indicate that hypovolaemia also affects ion transport in the tracheal membrane. Furosemide and hypovolemia have no acute effects on respiratory mucus properties.
Assuntos
Diuréticos/farmacologia , Furosemida/farmacologia , Hipovolemia/fisiopatologia , Muco/efeitos dos fármacos , Traqueia/efeitos dos fármacos , Doença Aguda , Animais , Anuros , Cães , Hipovolemia/induzido quimicamente , Técnicas In Vitro , Masculino , Potenciais da Membrana/efeitos dos fármacos , Depuração Mucociliar/efeitos dos fármacos , Distribuição AleatóriaRESUMO
To explore the role of oxytocin in the regulation of salt appetite and blood pressure, we conducted studies in oxytocin gene-knockout mice and determined (1) blood pressure and heart rate during day and night periods, (2) salt appetite after iso-osmotic volume depletion, and (3) salt appetite and blood pressure after central injection of angiotensin II. Long-term arterial catheters were inserted, and blood pressure and heart rate were recorded for 24 hours. There was a modest decrease in blood pressure and heart rate in knockout mice. Salt appetite was measured with a 2- bottle choice (water and 2% NaCl), with measurement of licking activity. Mice were injected subcutaneously with 30% polyethylene glycol (0.5 mL), and voluntary intakes were measured for 24 hours. Knockout mice consumed 3 times the amount of NaCl than did controls, 276+/-77 vs 90+/-38 licks/24 h (P<0.05). Water consumption was similar between groups. Angiotensin II (5, 50, and 200 ng/3 microL) injected intracerebroventricularly produced dose-related increases in intake, with no differences between the groups. The 50-ng dose of angiotensin II elicited salt and water intakes of 151+/-43 vs 160+/-33 licks and 250+/-53 vs and 200+/-51 licks, respectively (control vs knockout). The pressor response to angiotensin II was not different between the groups. Results suggest that oxytocin plays a role in the regulation of blood pressure and salt appetite, specifically as mediated by volume receptors, and that the renin-angiotensin system is not involved in these changes.