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Objective:To design a laparoscopic partial renal blood flow blocker (LPRB), and to explore the design rationality and effect of LPRB on blocking the blood flow of local renal tissue in rabbit kidney experiment.Methods:⑴ Design.According to the anatomical characteristics of the renal blood flow from the center to the periphery in the human, pig and rabbit, the blood flow at the distal part of the compression area could be blocked by the compression of the medial kidney tissue. LPRB included the first pressure arm, the second pressure arm and shaft. A built-in torsion spring made the two ends of the pressure arm to automatically close. The ends of pressure arm were provided with an arc-shaped compression component, on which, there were multiple adaptive compression plates. ⑵ Fabrication. 3D printer printed the finished product with titanium alloy material. ⑶ Animal experiments. Five New Zealand rabbits were anesthetized and fixed on the operating table in a semi-lateral position, with a lateral abdominal incision. Kidneys were exposed, only the renal pedicle vessels were retained. According to different methods of blocking blood flow, they were divided into conventional group and LPRB group for self-control. The effect of blocking blood flow was observed. The clamping force of LPRB was detected, and the degree of tissue damage at the clamping site was observed by naked eye and pathology.Results:LPRB had been licensed as a utility model and apperance patent. The device was successfully made from titanium alloy by 3D printer. In the experiment, the device was easily placed and removed. The two pressure arms were automatically closed and fixed under the action of torsion spring. The angle of the compression arm could be adjusted according to the position of clamping. The self-adaptive compression plates might be inclined in order to be consistent with the shape of the kidney; The pressure of LPRB was sufficient and the hemostasis was complete.Conclusions:LPRB is basicly rational and safe, and it can realize the partial hemostasis of the excised part and guarantee the blood flow of other parts at the same time. However, the larger size and harder adaptive component need to be improved in the future.
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Abstract We present the clinical case of a 39 year old male that presented with a violent death in the city of Medellin. During the necropsy, a horseshoe Kidney was found, which was never diagnosed according to the patients' medical history. It is a case relevant in the medical field given the unusual vasculature that was found, because it's not a usual arrangement. The lack of symptoms and its spontaneous finding during the necropsy, shows us that it's not a rare find in our environment and that it has a big impact in the surgical fields, and in occasions, with urinary tract infections. Methodology: Descriptive. Informed consent was given by the deceased relatives for the use and analysis of the medical history.
Resumen Se expone el caso de un hombre de 39 años que presenta muerte violenta en la ciudad de Medellín. Durante la necropsia se encuentra un riñón en herradura, que no tuvo diagnóstico clínico en su momento, según los hallazgos en su historial médico. Es un caso que puede tener implicaciones en el campo médico, dada la vasculature accesoria que presenta, presentación que no es comúnmente observada. La falta de sintomatología y su hallazgo espontáneo durante la necropsia hacen ver que, a pesar de la poca incidencia, no es extraño encontrar el caso en pacientes de nuestro entorno. Este tiene mayor impacto en el campo quirúrgico y, en ocasiones, en las afecciones urinarias. Metodología: descriptivo. Se obtuvo consentimiento informado, de la familia del occiso, para el estudio de su historial médico.
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Humans , Male , Female , Fused Kidney , Kidney , Renal Circulation , ColombiaABSTRACT
Purpose To explore the influence of duration of scan acquisition on perfusion parameters in whole renal perfusion with Revolution CT.Materials and Methods Fortytwo patients without pathologic changes in bilateral kidneys were divided into group A (with short perfusion time) and group B (with long perfusion time) according to the duration time of the perfusion scan.The Revolution CT axial scan mode was used for perfusion scan,and the width of detector was 16 cm.The perfusion CT series were performed in 50 seconds,each comprising 25 volumes with identical parameters (80 kVp,200 mA) in group A.The perfusion CT series were performed in 594 seconds,each comprising 23 volumes with identical parameters (120 kVp,55 mA) in group B.The source datasets were post-processed with CT Perfusion 4D software,and the perfusion parameter maps were obtained when right renal abdominal aorta was taken as entry artery.Perfusion parameters of bilateral kidneys were compared within and between group A and group B,respectively.CT dosage index of volume (CTDIvol) and dose length product (DLP) were recorded.The effective dose (ED) was calculated and compared.Results There were no statistical difference in all parameters between bilateral kidneys within each group (P＞0.05).However,blood volume,time to peak,and permeability surface in the cortex and medulla of bilateral kidneys all showed differences between the above two groups (P＜0.05).The mean transit time in the medulla between the two groups was different (P＜0.05),but neither the blood flow in the medulla and cortex nor the mean transit time of the cortex had difference between the two groups (P＞0.05).The effective radiation doses were (23.10± 4.39)mSv in group A and (23.19±0.00) mSv in group B,respectively (without statistic difference:P＞0.05).Conclusion CT perfusion parameters with different duration time show differences in whole renal perfusion;therefore,scanning time needs to be set according to the clinical application.
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Objective:To investigate the significance of filtration fraction (FF) and renal artery stenting in the treatment of atherosclerotic renal artery stenosis.Methods:In the study,42 cases of renal artery stenosis were treated with 52 renal artery stent implantation.Percutaneous transluminal renal angioplasty and stent (PTRAS) of the patients' health side kidney,ipsilateral kidney (renal) glomerular filtration rate (GFR),renal effective renal plasma flow effective renal plasma flow (ERPF),kidney filtration fraction changes of preoperative and postoperative serum creatinine (SCR) and the changes in the patients with blood pressure (SBP) and the changes after taking antihypertensive drugs were observed and analyzed.Results:The 52 cases of renal artery stent implantation were all successful.Preoperative ipsilateral GFR was significantly lower than that of normal side (t =-3.989,P =0.000);preoperative ipsilateral ERPF was significantly lower than the contralateral side (t =-4.926,P =0.000).On both sides,the overall FF values were equal (t =1.273,P =O.207).Postoperative ipsilateral renal GFR was increased,but there was no statistical difference (t =-1.411,P =0.164).Postoperative ipsilateral renal ERPF was increased significantly (t =-4.954,P =0.000),and FF lower (closer to the normal value (t =3.274,P =0.002).Postoperative side GFR was significantly reduced (t =2.569,P =0.000),the contralateral ERPF was significantly reduced (t =3.889,P =0.001),and FF had no significant change (t =-0.758,P =0.454).Postoperative side GFR was lower than that of the contralateral (t =-3.283,P =0.002) and postoperative side ERPF was still lower than that of the contralateral (t =-3.351,P =0.001),but on both sides,the FF values were equal (t =-0.361,P =0.719).Preoperative FF was relatively normal in the patients with kidney,and the postoperative FF value change was small (t =O.799,P =O.430);preoperative FF was significantly higher in the patients with kidney,and the postoperative FF value was lower than the preoperative (normal value,t =5.299,P =0.000).Postoperative overall serum creatinine was significantly decreased (t =2.505,P =0.016);but for the patients with unilateral renal artery stenosis,the changes in serum creatinine had no statistical difference (t =1.228,P =0.299);and for the patients with bilateral renal artery stenosis and serum creatinine compared with the preoperative,the changes were decreased significantly (t =2.518,P =0.030);postoperative blood pressure (SBP) was significantly decreased compared with that before operation (t =8.945,P =0.000);antihypertensive drugs taken were decreased significantly compared with the preoperative (t =5.280,P =0.000).Conclusion:For the patients with renal artery stenosis,FF is a useful index to understand the pathophysiological process of renal ischemia.Whether preoperative FF is significantly increased or FF is relatively normal,should be regarded as the indications of renal artery stent implantation.
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Purpose To investigate the value of arterial spin labeling (ASL) in evaluating renal function in patients with renal cell carcinoma (RCC) after laparoscopic partial nephrectomy.Materials and Methods Fifteen patients with RCC undergoing laparoscopic partial nephrectomy were studied prospectively.The patients were performed ASL scan one week before and three months after operation.The correlation between renal blood flow (RBF) value measured by ASL and the glomerular filtration rate (GFR) measured by radionuclide method in the renal cortex of healthy side was analyzed.The RBF values in the kidney of affected side or healthy side were measured,the difference of which between before operation and three months after operation was compared.Results The RBF value and GFR data in the renal cortex of healthy side had positive correlation (r=0.638,P＜0.05).In the affected side of kidney,the RBF value of remaining renal tissue [(291.5 ± 37.3) ml/(100g·min)] compared with that of preoperative renal tissue [(237.8 ± 46.2) ml/(100g·min)]increased about 53.7 ml/(100g · min) (P＜0.05).In the healthy side of kidney,the RBF value of renal tissue [(241.1 ± 50.3) ml/(100 g · min)] compared with that of preoperative renal tissue [(290.4 ± 51.8) ml/(100 g·min)] decreased about 49.3 ml/(100 g·min) (P＜0.05).Conclusion ASL can be used to evaluate renal function,and it is valuable to evaluate renal perfusion function after laparoscopic partial nephrectomy of RCC.
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Background: Renal blood flow evaluation during malaria illness is rarely done despite the high incidence of kidney injury from malaria and availability of Doppler ultrasound scanners in malaria endemic areas. Aims: This study is to evaluate the renal blood flow changes using Doppler ultrasonography among uncomplicated and complicated malaria subsets of pediatric patient with laboratory evidence of malaria parasitemia and without background clinical and laboratory evidence of renal impairment. And to compare these with parameters of age matched healthy pediatric control. Study Design: This was a prospective case control study of renal Doppler indices in children with acute malaria. Place of Study: The study was conducted among pediatric patients presenting at the children outpatient clinics, emergency and pediatric wards of the University College Hospital (UCH), Ibadan Nigeria. Methodology: Doppler indices of 602 kidneys were evaluated among 85 uncomplicated (UM), 85 complicated malaria (CM) children that presented within 24 hours and follow up scans on days 3 and 5 of their illness. These were compared with that of 131 healthy children (control). Results: The main renal artery diameter of the CM group was 0.41±0.07 mm, UM=0.48±0.09 mm and 0.53±0.11 mm (p=<0.001) in the control group. The main renal vein diameter were 0.59±0.11 mm and 0.48±0.10 mm and 0.63±0.15 mm (P=<0.000) among the CM, UM and the control group respectively. The PSV and EDV were slightly lower in the malaria groups than in the control group. PSV=49.01±18.21 cm/s in the UM and CM=50.71±19.68 cm/s. The control group PSV was 56.95±15.47 cm/s. AT was however significantly lower in the two malaria subgroups than in the control. (UM=47.70±18.28 cm/s, CM=52.33±21.06 cm/s and control=75.20±27.66 cm/s respectively (p=<0.000). The Intrarenal S/D in UM was 2.73±0.49 and the CM group S/D was 3.05±0.65 and control=2.62±0.47 (P=0.04). Slightly lower but statistically insignificant mean values were seen in the RI and PI. Conclusion: The main renal arterial and vein diameters and the intra renal vessel AT are significantly reduced during acute falciparum malaria illness. The intra-renal PSV and EDV are likely to be lower in acute falciparum malaria than in the normal healthy children. The intra-renal S/D are significantly higher in the UM and CM. Also, the PI and RI are likely to be higher in the malaria groups. The AT and S/D both showed inverse and direct relationship respectively as malaria severity worsens. We propose that renal Doppler ultrasound can be used to monitor renal status and should be included in the management of children with acute malaria infection more so in malaria endemic area.
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Obesity has been associated with a multitude of co-morbid conditions, most importantly with diabetes mellitus and cardiovascular diseases. Diet is one of the major key factors of a successful weight management schemes to ensure a healthy weight. High protein, low carbohydrate and low fat diets are reported to be effective for weight management and gained particular popularity in the recent past. As a result, most individuals have shifted to high protein diet in an attempt to lose weight or maintain a healthy weight or body composition. On the other hand, high dietary protein is well known to increase renal blood flow and glomerular filtration rate and may potentially increase the future risk of renal disease due to increased glomerular pressure and hyperfiltration injury. The mechanism by which protein diet acts on the kidney is not well known; however, multiple potential mechanisms have been postulated. This review discusses the possible mechanisms through which dietary protein intake may influence renal function parameters.
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Objective To explore the change characteristics of early renal blood infusion in patients with diabetes and its relation-ship with fasting blood sugar by using multi-slice spiral CT (MSCT)perfusion scan.Methods Thirty cases of T2DM patients within five years of disease course that meet clinical diagnostic criteria (poor DN glycemic control group and good DN glycemic control group with 1 5 cases in each group)and 1 5 cases in the control group underwent bilateral renal perfusion scan using 64-detector spiral CT,thus obtaning their cortical perfusion parameters of bilateral kidneys,including blood flow (BF),blood volume (BV),mean transit time (MTT)and capillary permeability surface (PS).At the same time,for each case,fasting glucose,blood urea nitrogen, serum creatinine and blood uric acid value on the third days after and before perfusion were also measured;the glomemlar filtration rate (C-GFR)was estimated.Statistical analysis was performed on all of these obtained values.Results (1).For the poor DN gly-cemic control group,the average BF value,average BV value and average PS value were reduced,average MTT was prolonged sig-nificantly,and compared with normal group,average BF value and average MTT were statistically significant (P 0.05)for both normal control group and DN groups in the third day before and after renal CT perfusion imaging examination.Conclusion BF,BV and MTT of MSCT perfusion scan can reflect the characteris-ticsof early renal blood infusion in patients with diabetes.And changes of fasting blood sugar in patients with diabetes may influence mean BF and mean MTT of kidney.
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Objective To observe the effects of angiotensin Ⅱ( Ang Ⅱ) blockade on renal function, renal blood flow and renal oxygen consumption in chronic renal failure ( CRF) rats induced by 5/6th kidney ablation /infarction (5/6A/I).Methods Sprague-Dawley rats were randomly divided into 3 groups:the normal group (group A, n =14), mod-el group (group B, n=14) and angiotensin II blockade (Cozaar with Monopril) treatment group (group C, n =14).The chronic renal failure ( CRF) rat models were induced by 5/6th kidney ablation/infarction.The tail artery systolic pressure (SBP), diastolic blood pressure (DBP) and tail vein serum creatinine (Scr), blood urea nitrogen (BUN), hemoglobin ( Hb) and creatinine clearance rate ( Ccr) were assessed before and after intervention.The course of treatment was sixty days.The renal blood flow ( RBF) , blood gas analysis of abdominal aortic and renal vein, left renal vein pressure ( RV-pO2 ) were detected and remnant renal oxygen consumption ( QO2/TNa ) was calculated, and the pathological changes of remnant kidney were observed after the 60 d intervention.Results (1) Compared with the group A, the levels of Scr, BUN and tail artery SBP, DBP were significantly increased ( P<0.01 for all) , and the levels of Ccr and Hb were signifi-cantly decreased ( P<0.01) in the groups B and C, demonstrating the successful modeling.(2) Compared with the group B, the levels of Scr, tail artery SBP, DBP and QO2/TNa were significantly decreased (P<0.01 for all), the levels of BUN were decreased (P<0.05), the levels of Hb, Ccr and RVpO2 were significantly increased (P<0.01 for all), the level of RBF was increased ( P<0.05) in the group C after intervention.(3) The histopathological examination of the remnant re-nal tissue showed that the pathological changes in the group C were apparently reduced, better than those of the Group B. Conclusions Angiotensin II blockade can increase RBF, reduce renal oxygen consumption, improve renal function, and reduce the renal pathological changes in CRF rats.The mechanism of renal protection may be related to the regulation of cellular energy metabolism and improvement of renal oxygen consumption.
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Purpose To evaluate infrared thermometer (IRT) accuracy compared to standard digital thermometer in measuring kidney temperature during arterial clamping with and without renal cooling. Materials and Methods 20 pigs weighting 20Kg underwent selective right renal arterial clamping, 10 with (Group 1 - Cold Ischemia with ice slush) and 10 without renal cooling (Group 2 - Warm Ischemia). Arterial clamping was performed without venous clamping. Renal temperature was serially measured following clamping of the main renal artery with the IRT and a digital contact thermometer (DT): immediate after clamping (T0), after 2 (T2), 5 (T5) and 10 minutes (T10). Temperature values were expressed in mean, standard deviation and range for each thermometer. We used the T student test to compare means and considered p < 0.05 to be statistically significant. Results In Group 1, mean DT surface temperature decrease was 12.6 ± 4.1°C (5-19°C) while deep DT temperature decrease was 15.8 ± 1.5°C (15-18°C). For the IRT, mean temperature decrease was 9.1 ± 3.8°C (3-14°C). There was no statistically significant difference between thermometers. In Group 2, surface temperature decrease for DT was 2.7 ± 1.8°C (0-4°C) and mean deep temperature decrease was 0.5 ± 1.0°C (0-3°C). For IRT, mean temperature decrease was 3.1 ± 1.9°C (0-6°C). No statistically significant difference between thermometers was found at any time point. conclusions IRT proved to be an accurate non-invasive precise device for renal temperature monitoring during kidney surgery. External ice slush cooling confirmed to be fast and effective at cooling the pig model. IRT = Infrared thermometer DT = Digital contact thermometer D:S = Distance-to-spot ratio .
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Animals , Male , Body Temperature , Infrared Rays , Kidney/surgery , Thermometers/standards , Cold Ischemia , Constriction , Equipment Design , Medical Illustration , Reference Values , Reproducibility of Results , Surface Properties , Sus scrofa , Time Factors , Warm IschemiaABSTRACT
Background & objectives: Regulation of renal function and haemodynamics are under a direct control from the renal sympathetic nerves and renal denervation produces overt diuresis and natriuresis in several mammalian species. However, the inter-related series of changes in renal function and haemodynamics following acute renal denervation (ARD) is not fully understood. Thus, we aimed to investigate and relate the changes in renal function and haemodynamics following acute unilateral renal denervation in anaesthetized Sprague Dawley (SD) rats. Methods: Male SD rats were fasted overnight, anaesthetized with sodium pentobarbitone (60 mg/kg ip), denervated by application of phenol to the left renal artery and maintained on an intravenous (iv) infusion of isotonic saline for 2 h. Throughout this period, six urine and plasma samples were taken at 20-min intervals to study kidney function parameters. In a different set of experiments, renal nerve stimulation (RNS) was carried out to characterize the changes in renal vasoconstrictor responses following ARD. Results: Denervated animals showed significantly (P<0.05 vs. control innervated rats) higher urine flow rate (UFR), absolute sodium excretion (UNaV), fractional sodium excretion (FENa) and glomerular filtration rate (GFR). The renal vasoconstrictor responses to RNS were significantly (P<0.05) lower in denervated rats as compared to the innervated counterparts. However, no appreciable differences were seen in the mean arterial pressure (MAP), plasma sodium (PNa), basal renal blood flow (RBF) and basal renal vascular resistance (RVR) in both innervated and denervated SD rats. Interpretation & conclusions: Natriuresis, diuresis, enhanced GFR and impaired vasoconstriction in response to RNS are typical and instant responses to ARD in SD rats. Renal sympathetic nerves serve more important role in salt and water conservation than in dynamic autoregulation of RBF under normal sympathetic tone; yet, their effects on renal haemodynamics become more evident in the presence of augmented renal sympathetic nerve activity (RSNA).
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Animals , Diuresis , Hemodynamics , Kidney/innervation , Kidney/physiology , Male , Phenol/administration & dosage , Rats , Rats, Sprague-Dawley , Sympathectomy, ChemicalABSTRACT
Objective To investigate the changes in renal blood flow during laparoscopic cholecystectomy.Methods Thirty-two ASA Ⅰ patients (10 male, 22 female) aged 18-64 yr, weighing 45-81 kg undergoing laparoscopic cholecystectomy were included in this study. Anesthesia was induced with midazolam, fentanyl,propofol and vecuronium and maintained with isoflurane inhalation, continuous infusion of propofol and remifentanil and intermittent iv boluses of vecuronium. The patients were intubated and mechanically ventilated. PET CO2 was maintained at 30-40 mm Hg. The probe of transesophageal echocardiography (TEE) was inserted into esophagus after tracheal intubation. The internal diameter and blood flow velocity and time integral of left renal artery and descending aorta were measured by TEE before (baseline) and at 1, 5, 10, 15, 20 and 30 min of pneumoperitoneum and 1 and 5 min after deflation. The blood flow of left renal artery (LRAF) and decending aorta (DAF) were calculated. The maximal decrease in LRAF and DAF and LRAF/DAF were analyzed. Results LRAF and DAF decreased significantly during pneumoperitoneum compared to the baseline and recovered after deflation. LRAF and DAF decreased maximally by 40% (95% confidence interval (95% CI) 31%-49% ) and 38% (95% CI 31%-44% ) at 8.9 min (95% CI 5.5-12.4 min) and 6.7 min (95% CI 4.0-9.5 min) of pneumoperitoneum respectively. There was no significant change in LRAF/DAF ratio during pneumoperitoneum. Conclusion The renal blood flow decreases at 1-30 min of pneumoperitoneum with the maximum degree of decrease about 40% at about 9 min of pneumoperitoneum and the reason is related to the decrease in the cardiac output.
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Objective To determine the accuracy of renal blood flow assessment by transesophageal echocardiography (TEE) during carbon dioxide (CO2) pneumoperitoneum.Methods The left renal arterial diameter (RAD) and the Doppler velocity time integral (VTI) were measured by TEE before peumoperitoneum (T0, baseline), at 1, 5, 10, 15, 20 and 30 min of pneumoperitoneum and 1 and 5 min after deflation in 35 patients undergoing elective laparoscopic cholecystectomy. The left renal blood flow (LRBF) and the left renal blood perfusion resistance (LRPR) were calculated according to the following formulae: LRBF = 1/4π x RAD2 x VTI x HR, LRPR = MAP/LRBF.Three months later, the TEE images of 10 cases were randomly selected and reviewed by the same and another research team member to check the repeatability and consistency of the LRBF determination during operation, respectively. The quality of the TEE images was evaluated by another specialist.Results Before pneumoperitoneum, 94% of the TEE images were rated as satisfactory. There was no significant difference between the qualities of the TEE images obtained before and during pneumoperitoneum. The variabilities between the RADs measured by TEE during and 3 months after operation were 9.28% by the same team member and 8.71% by another team member. The variabilities between the VTIs measured by TEE during and 3 months after operation were 5.61% by the same team member and 6.25% by another team member. The linear regression analysis of the LRBF showed that the slope and the intercept were 1.05 and 31.4 ml/min respectively by the same member and 0.92 and 47.3 ml/min respectively by another member. The LRBF was decreased during pneumoperitoneum and the LRPR was increased.Conclusion TEE can be used to accurately monitor the changes in renal blood flow during CO2 pneumoperitoneum.
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Objective To investigate the impact on the endothelial cell function and renal blood flow through effective treatment for elderly patients with hypertension. Methods 64 cases of elderly hypertensive patients over 70years old with effective treatment, according to pre-treatment blood pressure, were divided into two groups: hyptension level-2 group(30cases) and hypertension level-3 group(34cases), and 30 cases of elderly people with health physical examination during the same period were setlected as the control group. Endothelial cell function was detected, including the endothelin-1 (ET-1)、 nitrous oxide (NO), thromboxane B2 (TXB2)、 6-keto-prostaglandinF1α (6-K-PDGF1α) in plasma. Renal blood flow was explored by color doppler ultrasonic instrument ,involving peak velocity in systole(PSV) and lowest velocity in end-diastole(EDV) of renal arteries, segmental arteries and interlobar arteries.After indicators had reached the standard 1 month in the hypertension level-2 and hypertension leve1-3 patients with effective antihypertensive therapy, the difference of ET-1, NO, TXB2,6-k-PGF1o and PSV, EDV among the three groups were compared. Results The differences were statistically significant in ET-1, NO, TXB2,6-k-PGF1α, PSV and EDV before treatment among three groups (P ＜ 0.05). After blood pressure treated had reached the standard 1 month,indicators were no statistically meaningful difference among the three groups (P ＞ 0.05). Conclusion After effective clinical treatments, the endothelial cell function and renal blood flow of the elderly hypertensive patients can be improved. At the same time, to delay renal damage in elderly patients with hypertension provide a theoretical basis.
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Objective To explore the changes of renal blood flow and renal injury in neonates with birth asphyxia. Methods Seventy-one patients were tested for Ultrasonic Doppler renal blood flow and renal function. Results The blood perfusion resistance was increased and the blood flow perfusion was decreased, Even in light asphyxia. Conclusion The hemodynamic disturbance is the main reason for renal injury and dysfunction in infants with birth asphyxia, and detecting hemodynamic disturbance and urinary enzyme may be an early diagnostic method to evaluate the renal injury.
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Renal plasma flow (RPF) and glomerular filtration rate (GFR) are decreased in patients with heat stroke. Heat stroke after prolonged exercise under high temperatures is usually associated with hypotension and dehydration, leading to decreased RPF. However, whether renal blood flow (RBF), RPF, and GFR are increased or decreased during immersion in mild warm water remains unknown.<br>Para-aminohippurate clearance (C<sub>PAH</sub>), sodium thiosulfate clearance (C<sub>thio</sub>), and creatinine clearance (C<sub>cr</sub>) were determined in 14 healthy men aged 19 to 27 years old (mean±SD, 22±2), 161 to 181cm (171.5±6.3) tall, and weighing 52 to 78kg (64.2±7.4) without immersion at about 25°C (room temperature) and during immersion in water at 41±0.5°C.<br>C<sub>PAH</sub>, C<sub>thio</sub>, and RBF significantly increased during immersion compared with those without immersion (P<0.0001, P<0.03, P<0.0001, respectively). C<sub>cr</sub> did not change (P=0.108). The filtration fraction (FF) was significantly decreased (P<0.001). Levels of plasma atrial natriuretic peptide, aldosterone, anti-diuretic hormone and renin did not significantly differ between these two conditions.<br>This investigation suggests that daily immersion at 41°C is beneficial for renal function.
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@#ObjectiveTo investigate the long term effect of different antihypertensive agents on renal hemodynamics with ultrasound Doppler.Methods52 essential hypertensive patients were divided into three groups according to the antihypertensive agent they took: angiotensin-converting-enzyme inhibitor (ACEI), calcium channel blocker (CCB) and β-adrenoceptor blocker (βB). The blood pressures of right upper arms were measured with mercury column blood pressure gauge using Korotkoff method. Renal hemodynamics were examined with ultrasound Doppler before and after treatment with agents. ResultsSystolic blood pressure (SBP) and diastolic blood pressure (DBP) of all patients were decreased significantly. An significant correlation was found between the deceases of blood pressure and the betterment of renal homodynamic parameters in ACEI and CCB groups, but not in βB group. ConclusionTo a degree, the betterment of renal hemodynamics is correlation with the reduction of systemic blood pressure and mechanism of action of antihypertensive agents.
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BACKGROUND: The incidence of renal insufficiency is reported about 18-27% during the thoracoabdominal aneurysm surgery. The possible mechanisms are reduction and maldistribution of renal blood flow, activation of renin angiotensin system, release of various mediators. In this study, we observed the effect of nicardipine, one of the calcium channel blockers that commonly used, on the systemic hemodynamics and the renal fuctions. METHODS: A total of 13 mongrel dogs were divided into two groups: control group (C, n = 7), nicardipine administration group (N, n = 6). After brachial arterial and Swan-Ganz catheterization, midline abdominal incision was made. For the aortic cross clamping the supraceilac aorta was exposed and the doppler flowmeter probe was placed on the left renal artery. The thermal diffusion microprobe was inserted in the renal parenchyme to measure local renal perfusion. At sixty minutes after aortic cross clamping, systemic hemodynamic data, renal blood flow and local renal perfusion were measured and at 1, 2, 3, 4, 5 and 6 hours after unclamping the same parameters were measured. RESULTS: There were no differences on renal blood flow, renal perfusion and oxygen extraction ratio between two groups. The renal blood flow and renal perfusion did not recover to the baseline level after unclamping in both groups. The plasma renin activity, serum creatinine concentration and cystatin-c did not show any difference between groups respectively. CONCLUSIONS: We concluded that the administration of nicardipine after supraceliac aortic unclamping to improve the renal function was not effective in experimental dogs.
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Animals , Dogs , Aneurysm , Aorta , Calcium Channel Blockers , Catheterization, Swan-Ganz , Constriction , Creatinine , Flowmeters , Hemodynamics , Incidence , Nicardipine , Oxygen , Perfusion , Plasma , Renal Artery , Renal Circulation , Renal Insufficiency , Renin , Renin-Angiotensin System , Thermal DiffusionABSTRACT
OBJECTIVE:To research the mechanism of action of compound Huanggan gr anules(FHG) METHODS:To observe the effect of FHG on the renal blood flow and glomerular filtration rate,and its mechanism of diuresis by means of isotopic tracer,electromagnetic flowmeter and ureter catheterization RESULTS:FHG could significantly increase the renal blood flow and glomerular filtration rate,and enhance the diuresis CONCLUSION:Its diuresis is based on the increase of rena l blood flow and glomerular filtration rate,which results in the decrease of ne phrotoxic substances such as blood urea nitrogen and serum creatinine
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BACKGROUND: Norepinephrine, which is frequently administered as a vasopressor to the patients with septic shock, can decrease splanchnic and renal blood flows and aggravate splanchnic and renal ischemia. The low-dose dopamine (LDD) has been frequently combined with norepinephrine to ameliorate renal and splanchnic hypoperfusion in patients with septic shock. However, the effect of the LDD on the splanchnic and renal blood flow has not been fully elucidated. This investigation was carried out to determine the effect of the LDD on the splanchnic and renal blood flow in the patients with septic shock under the treatment of norepinephrine. METHODS: Eleven patients with septic shock were included in this study. All of them were under the norepinephrine treatment as the mean arterial pressure (MAP) was less than 70 mm Hg in spite of the adequate fluid resuscitation. With stabilization of MAP, the LDD (2 g/kg/min) was administered for two hours in each patients. Hemodynamics, gastric intramucosal pH (pHi), gastric regional PCO2 (rPCO2), rPCO2 - PaCO2, urine volume, urine sodium excretion and creatinine clearance were compared between with and without the LDD infusion. Diuretics was not used during the study period. RESULTS: Age of patients (n=11) was 64 12 and the APACHE III score was 84 17. The mortality rate of the subjects was 64%. Dosage of norepinephrine was 0.55 0.63 g/kg/min during the study period. There were no significant differences in hemodynamics (central venous pressure, cardiac output, pulmonary artery occlusion pressure, mixed venous gas), pHi, rPCO2, rPCO2 - PaCO2 depending on the concomitant infusion of the LDD. The volume of urine tended to increase (P=0.074) after concomitant LDD, but the changes in urine sodium excretion and creatinine clearance were not significantly different. CONCLUSIONS: The combined infusion of the LDD with norepinephrine did not improve splanchnic and renal blood flow in the patients with septic shock.