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PubMed1986

Late hemodynamic sequelae of deep venous thrombosis.

Twenty-nine limbs in 19 patients who had deep venous thrombosis documented by phlebography were studied by hemodynamic techniques 2 to 13 years later (mean, 7 years). Two limbs were found to be "normal." Nine limbs were hemodynamically obstructed; the remaining 18 limbs had developed reflux abnormality. All of the nine limbs with obstruction demonstrated symptoms of severe swelling or ulceration. In contrast, limbs with valve reflux were either asymptomatic or had only mild to moderately severe symptoms. Correspondingly, the reflux hemodynamic derangement was also mild, with reflux confined to a single level (commonly the popliteal valve). The implications of the differences in clinical presentation and hemodynamic profile between this group with post-thrombotic valve reflux and the typical patient with stasis caused by chronic venous insufficiency are explored. The natural history of stasis sequelae of deep venous thrombosis has apparently changed somewhat since the introduction of anticoagulation therapy.

Arm↗
PubMed2000

Effective hemodynamic diameter: an intrinsic property of vein grafts with predictive value for patency.

INTRODUCTION: Conduit size and quality are major determinants of the long-term success of infrainguinal autologous vein grafting. However, accurate measurement of the internal diameter of vein grafts is difficult given their variable wall thickness and taper. The purpose of this study was to define the "effective" internal diameter of a vein graft according to its hemodynamic properties and to determine its significance for graft patency. METHODS: Sixty infrainguinal bypass grafts performed on 57 patients were evaluated intraoperatively. Proximal and distal graft pressure and blood flow (Q(meas)) were measured with fluid-filled catheter transduction and ultrasonic transit-time flowimetry, respectively, after unclamping. Waveforms were recorded digitally at 200 Hz under baseline conditions and after stimulation with 60 mg of papaverine. According to Fourier transformation of the measured pressure gradient (DeltaP), the Womersley solution for fluid flow in a straight rigid tube was used to calculate theoretical flow waveforms (Q(calc)) for a range of graft diameters. The theoretical waveforms were then compared with the measured flow waveforms and the best-fit diameter chosen as the "effective hemodynamic diameter" (EHD). Only grafts in which the correlation coefficient of Q(calc) versus Q(meas) was more than 0.90 were accepted (n = 47) to assure validity of the hemodynamic model. After a mean follow-up of 12.5 months (range, 0.1-43.9 months), patency was determined by the life table method. Hemodynamic and clinical variables were tabulated, and their effect on patency determined the use of univariate and multivariate Cox regression. RESULTS: Mean EHD was 4.1 +/- 0.1 mm with a range of 2.5 to 5.7 mm. Administration of papaverine caused profound changes in DeltaP (+78% +/- 17%) and Q(meas) (+71% +/- 12%) as expected, but had no effect on EHD (+0.05% +/- 0.1%). Univariate regression identified five variables associated with decreased secondary patency (P <.10): low EHD, conduit source other than the greater saphenous vein, high baseline DeltaP(mean), female sex, and redo operation. Of these, only low EHD was significant after multivariate analysis (P =.03). Patency of small diameter grafts (EHD < 3.6 mm; n = 11) was compared with patency of larger grafts (EHD > 3.6 mm; n = 36) to test a frequently espoused clinical guideline. Grafts with an EHD less than 3.6 mm exhibited significantly lower secondary patency compared with larger grafts (P =.0001). The positive and negative predictive values for an EHD less than 3.6 mm for secondary graft failure for grafts with at least 1 year follow-up were 86% and 88%, respectively. CONCLUSION: An EHD is a unique parameter that quantifies conduit size and has a significant impact on vein graft patency. An EHD less than 3.6 mm portends graft failure.

Aged↗
PubMed2001

A 1-year follow-up quality of life study after hemodynamically successful or unsuccessful surgical revascularization of lower limb ischemia.

PURPOSE: The impact of hemodynamically successful or unsuccessful bypass grafting or angioplasty on patients' quality of life was assessed throughout the first year postsurgery. METHODS: A total of 146 patients, 97 patients who underwent successful revascularization and 49 patients who underwent unsuccessful revascularization, were assessed for quality of life with the Nottingham Health Profile. RESULTS: Hemodynamically successful revascularization resulted in an immediate and lasting impact on the patients' quality of life. Despite hemodynamic failure, patients had improvements in pain, emotional reactions, sleep, and family relationships at the 1-year follow-up assessment. A successful revascularization in patients with claudication demonstrated the most marked quality of life benefits, including all health dimensions that were not normal at baseline. Patients with critical ischemia had improved quality of life for pain, sleep, and physical mobility. High ankle pressure, in the claudicant group, and a high sense of coherence were significantly associated with high quality of life. CONCLUSION: The treatment of lower limb ischemia resulted in an immediate and relatively lasting improvement in patients' quality of life. Patients who underwent hemodynamically successful bypass grafting procedures or angioplasty demonstrated higher quality of life benefits than patients who underwent a failed bypass grafting procedure. Quality of life was further determined by means of the patients' sense of coherence.

Aged↗
PubMed2003

Comparison of abdominal aortic hemodynamics between men and women at rest and during lower limb exercise.

INTRODUCTION: Biologic variations between men and women have been hypothesized to contribute to the differences in atherosclerosis epidemiology of the two genders. Hemodynamics are also hypothesized to play an important role in the localization of atherosclerosis in the abdominal aorta. However, the hemodynamics of men and women have not been compared at this location at rest or during lower limb exercise conditions. METHODS: A magnetic resonance-compatible exercise bicycle, magnetic resonance imaging techniques, and custom data processing software were used to quantify blood flow rate, wall shear stress, and oscillations in flow and wall shear stress at the supraceliac and infrarenal levels of the abdominal aorta of young healthy men and women at rest and during lower limb exercise. RESULTS: Heart rate increased from 73 +/- 6.2 bpm at rest to 110 +/- 8.8 bpm during exercise (P <.0001). No statistical differences were found at the infrarenal level for mean blood flow rate (men, 0.9 +/- 0.4 L/min; women, 0.8 +/- 0.4 L/min) or mean wall shear stress (men, 1.2 +/- 0.5 dynes/cm(2); women, 1.4 +/- 0.7 dynes/cm(2)) at rest or mean blood flow rate (men, 5.9 +/- 1.3 L/min; women, 5.2 +/- 0.8 L/min) or mean wall shear stress (men, 5.1 +/- 0.8 dynes/cm(2); women, 5.4 +/- 2.1 dynes/cm(2)) during exercise. Also, no differences were seen in temporal flow and wall shear stress oscillations between men and women at rest or during exercise. Similarly, no significant hemodynamic differences were found between the genders at the supraceliac level. CONCLUSION: These similarities suggest that hemodynamics may not play a significant role in abdominal aortic disease differentiation between the genders and that biologic factors may be more important.

Adult↗
PubMed2001

Splanchnic and systemic hemodynamic effects of sustained euglycemic hyperinsulinemia in rats.

Insulin, in addition to its metabolic function, was found to induce skeletal muscle vasodilatation after acute administration. The vasoactive effects of sustained euglycemic hyperinsulinemia, especially in the splanchnic circulation, are less well known. The aim of this study was to evaluate the systemic and splanchnic hemodynamic effects of sustained euglycemic hyperinsulinemia. Hyperinsulinemia was induced by a sustained-release insulin implant in the scurf area of male rats (release rate -1 U/day). Beginning on the 3rd day, the study group was fed a glucose-rich diet. Hemodynamic studies were performed on the 5th day using the radioactive microsphere technique. Serum insulin was measured by radioimmunoassay. At the time of the hemodynamic measurements, plasma insulin level was higher in the insulin-treated (n=8) compared to control rats (n=8) (23.6 +/- 4.7 vs. 13.2+/-3.9 microu/mL, respectively; p<0.001). Plasma glucose level of the two groups was similar (5.43 +/- 1.07 vs. 5.83 +/- 1.44 mmol/L, respectively). Abdominal skeletal muscle blood flow was higher in the insulin-treated group (0.11 +/- 0.05 vs. 0.05 +/- 0.04 mL x min(-1) x g(-1), respectively; p<0.02). No significant changes were observed in cardiac output and renal blood flow. In the splanchnic circulation: stomach, pancreatic, intestinal, splenic, hepatic arterial and total hepatic blood flow were also not significantly different. In summary, short-term, sustained euglycemic hyperinsulinemia in rats increased blood flow to skeletal muscle but had no hemodynamic effects on cardiac output or splanchnic circulation.

Animals↗
PubMed1987

Systemic and renal hemodynamic consequences of manipulation of serum calcium and/or parathyroid hormone in the intact conscious mongrel dog.

Studies were undertaken in conscious mongrel dogs to separate the systemic and renal hemodynamic effects of alterations in serum calcium (Ca) from those of parathyroid hormone (PTH) in an intact conscious animal. Blood pressure was measured intra-arterially, cardiac output was determined by dye-dilution or thermodilution, total peripheral resistance (TPR) was calculated from standard formulae, and renal hemodynamics were estimated by the clearance of inulin and para-aminohippurate. Measurements were made before and after a 2 hour calcium chloride (CaCl2) infusion in 10 dogs (group 1). These animals had previously received a dose of PTH to prevent suppression of PTH during the CaCl2 infusion. Ionized calcium (Ca++) and TPR increased significantly. Blood pressure increased but not significantly. Administration of EDTA did not significantly change any systemic hemodynamic variable in eight thyroparathyroidectomized dogs (group 2). Chelation in seven dogs with intact parathyroid glands (group 3) reduced mean arterial blood pressure and total peripheral resistance. Renal hemodynamic measurements were not affected. Isolated acute elevation of serum Ca++, independent of suppression of PTH, increased total peripheral resistance. Decreased serum Ca++ required normal activity of parathyroids to reduce total peripheral resistance. The renal circulation was resistant to acute manipulation of ionized serum calcium and PTH. CaCl2 infusion to intact dogs (group 1) decreased serum magnesium significantly, increased urine flow rate, and decreased urinary PGE2 excretion. Comparisons between group 2 and group 3 revealed a greater decline in serum Mg and urinary prostaglandin E2 excretion in group 2 vs group 3. Elevation of peripheral resistance due to acute Ca elevations was accompanied by decreased serum Mg and decreased renal prostaglandin excretion.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2003

Hypertension and triglyceride catabolism: implications for the hemodynamic model of the metabolic syndrome.

OBJECTIVE: We sought to determine if hypertensive adults have a blunted triglyceride catabolic rate (TG K(2)) and if related hemodynamic and vascular alterations are determinants of TG K(2). METHODS: Fasting levels of insulin, glucose, lipoproteins and plasma catecholamines were measured in 10 normotensive and 10 hypertensive adults. TG K(2) was determined by an intravenous fat tolerance test. Forearm blood flow, maximum forearm blood flow and minimal forearm vascular resistance were determined by strain gauge plethysmography. Vascular compliance and systemic hemodynamics were measured by computerized arterial pulse waveform analysis. RESULTS: Compared to normotensives, hypertensives had a significantly elevated blood pressure (145 +/- 8/94 +/- 11 versus 111 +/- 15/74 +/- 14 mm Hg, p < 0.001), systemic vascular resistance (1695 +/- 441 versus 1172 +/- 430 dynes x sec x cm(-5), p = 0.02) and reduced large vessel compliance (11.7 +/- 3.6 versus 15.1 +/- 3.1 ml/mm Hg x 100, p = 0.04). There were no significant group differences in TG K(2) (3.07 +/- 2.01 versus 2.88 +/- 2.12 mg/dL/min, p = 0.85) or other metabolic and anthropometric variables. TG K(2) was not predicted by the forearm vascular measures or the hemodynamic variables, but was correlated to waist/hip ratio (r = -0.71, p = 0.001), fasting triglycerides (r = -0.64, p = 0.003), and male gender (r = 0.56, p = 0.012). An enhanced TG K(2) was independently predicted by a reduced small vessel compliance (r = -0.61, p = 0.006). CONCLUSIONS: Elevated blood pressure per se and hypertension-related hemodynamic and vascular alterations are not associated with reduced TG K(2) or other metabolic abnormalities. Rather, aspects of the insulin resistance syndrome are closely related to abdominal adiposity. The independent association between small vessel compliance and TG K(2) deserves further investigation.

Adult↗
PubMed2001

Plasma levels of natriuretic peptides and hemodynamic assessment of patent ductus arteriosus in preterm infants.

UNLABELLED: The main purpose of this study was to investigate whether circulating natriuretic peptides in premature infants reflect the hemodynamic significance of a patent ductus arteriosus (PDA). The study comprises 120 examinations in 55 premature infants with a mean gestational age of 27.2 wk and a mean birthweight of 933 g. Based on clinical and echocardiographic findings, the hemodynamic influence of ductal shunting was classified as small, moderate or large. Blood samples for N-terminal proatrial natriuretic peptide (Nt-proANP) and brain natriuretic peptide (BNP) were analysed after completion of the clinical part of the study. Linear regression indicated a very strong association between Nt-proANP and BNP (adjusted R = 0.89). The mean levels of Nt-proANP and BNP increased with the size of the shunt through a PDA, and peptide values followed hemodynamic alterations. The size of PDA accounted for 50% and 47% of the total variation in the plasma values of Nt-proANP and BNP, respectively. In detecting an echocardiographically significant PDA, the area under a ROC curve was 0.94 for Nt-proANP and 0.90 for BNP. CONCLUSION: The magnitude of shunting through a PDA is the main determinant of plasma levels of natriuretic peptides in premature infants. Nt-proANP and BNP seem to have the same pattern of secretion. Our findings indicate that measurements of natriuretic peptides may provide clinically relevant information in the hemodynamic assessment of premature infants.

Atrial Natriuretic Factor↗
PubMed2003

Duplex Doppler ultrasound assessment of clitoral hemodynamics after topical administration of alprostadil in women with arousal and orgasmic disorders.

There are limited hemodynamic data in women with arousal or orgasmic disorders and even fewer normative control hemodynamic data in women without sexual dysfunction. In addition, there is limited experience with topical vasoactive agents (used to maximize genital smooth muscle relaxation) applied to the external genitalia during hemodynamic evaluations. The aim of this study was to report duplex Doppler ultrasound clitoral cavernosal arterial changes before and after topical PGE-1 (Alprostadil) administration in control women and in patients with arousal and orgasmic sexual disorders. We found that women with sexual arousal and orgasmic disorders had significantly (p < 0.05) diminished clitoral peak systolic and end diastolic velocity responses compared to controls. Further research is needed to establish the diagnostic role of topical vasoactive agents in the hemodynamic evaluation of women with sexual dysfunction.

Administration, Topical↗
PubMed2004

Effects of altered volume loading on left ventricular hemodynamics and diastolic filling during hemodialysis.

BACKGROUND: Changes in the circulating volume associated with hemodialysis (HD) resulted in alternations of left ventricular (LV) filling. However, previous studies offered conflicting findings. This study thus evaluated the impact of HD on LV diastolic filling indices and hemodynamics. MATERIALS AND METHODS: Forty patients with end-stage renal disease were studied by Doppler echocardiography immediately before and after HD. The cardiac size, volume and mass were determined by M-mode and two-dimensional echocardiography. LV diastolic filling parameters and hemodynamics were assessed from mitral inflow using Doppler echocardiography. RESULTS: Left atrial and LV dimension, LV volume, and LV mass decreased significantly after HD (p<0.001). Cardiac output declined from 5.74+/-1.37 to 4.98+/-1.27 L/min (p<0.001), whereas, the ejection fraction remained unchanged. HD elicited marked changes in the early diastolic E (95.1+/-20.5 to 70.3+/-18.2 cm/s, p<0.001) and late atrial filling A velocities (104.3+/-20.9 to 88.9+/-16.9 cm/s, p<0.001). In addition, correction of the deceleration time of E and isovolumic relaxation time prolonged significantly (p=0.011 and p<0.001, respectively). CONCLUSIONS: Findings in this study indicate that HD altering the loading condition significantly influenced the LV diastolic function and hemodynamics. Moreover, Doppler echocardiography provides an effective means of assessing the effects on LV diastolic filling and hemodynamics during HD.

Adolescent↗
PubMed2004

Hemodynamic effects of arteriovenous fistula in end-stage renal failure.

Hemodynamic parameters using Swan Ganz catheter were studied in 17 patients with end stage renal disease. The acute effects of radiocephalic AV fistula on the hemodynamic parameters were studied at 24 hours of surgery. The chronic effects were studied in 8 of these patients at 6 weeks of arteriovenous (AV) fistula. The AV fistula matured in 3 to 4 weeks time and blood flow was sufficient for hemodialysis (400 mL/min). Patients with chronic renal failure had normal or high normal hemodynamic parameters. Six weeks after the AV fistula, the cardiac index and the stroke volume index slightly increased along with a significant increase in systolic and mean systemic arterial pressure. None of the patients had significant increase in cardiac filling pressures. Although there was some fall in systemic vascular resistance index and rise in cardiac index and stroke volume index, these changes were physically small and unlikely to put any extra hemodynamic load. Thus, AV fistula in dialysis patients is not an appreciable cause of circulatory or pulmonary congestion.

Adult↗
PubMed2003

Effects of intermittent exposure to high altitude on pulmonary hemodynamics: a prospective study.

Chronic alveolar hypoxia due to disease or low atmospheric pressure at high altitude results in the development of hypoxic pulmonary hypertension. The effects of intermittent hypoxia on pulmonary hemodynamics in healthy men have not been studied. We aimed to investigate, prospectively, pulmonary hemodynamics in workers commuting between an elevation of 3700 and 4200 m (4-week working shift) and lowland, below 500 m (4 weeks of holiday). Pulmonary hemodynamics has been investigated by Doppler echocardiography in 26 healthy Caucasian males, mean age 42 +/- 9 yr. First at lowland (760 m) and next during the fourth week of work at high altitude. Investigations were repeated in 21 subjects 1 year later at the end of the high-altitude exposure. The third series of investigations was performed 2 yr after the initial ones in 10 subjects who earlier had shown the strongest hypoxic vasoconstriction. At lowland, subjects presented with normal pulmonary hemodynamics. At high altitude, mean pulmonary artery pressure (PAPm) rose from 14.7 +/- 2.7 mmHg to 25.8 +/- 8.3 mmHg. One year later the PAPm remained unchanged in hypoxic conditions (25.0 +/- 7.3 mmHg). At the end of a 2-year follow-up of 10 "hyperreactors," PAPm measured at the end of the hypoxic exposure was the same as at the initial investigation, averaging 28 +/- 4.0, 28 +/- 3.5, and 29 +/- 2.5 mmHg at the beginning and at 1 and after 2 yr of intermittent exposure to high altitude. We concluded that intermittent exposure to 4000 m lasting 3 yr does not lead to development of permanent pulmonary hypertension.

Acclimatization↗
PubMed1989

Hemodynamic responses to converting enzyme inhibition in patients with renal disease.

We studied the effects of lisinopril on mean arterial blood pressure (MAP), plasma renin activity (PRA), and renal hemodynamics in nine patients with chronic renal disease and hypertension, before, and after three months of therapy. Lisinopril normalized blood pressure in five of nine patients (responders) and did not in the remaining four (nonresponders). PRA rose after lisinopril (4.8 +/- 2.6 ng/mL/h to 25 +/- 15 ng/mL/h, P less than 0.05) in responders, but not in nonresponders (2.0 +/- 1.4 ng/mL/h to 3.4 +/- 2.9 ng/mL/h). Glomerular filtration rate remained stable in both groups (responders: 43 +/- 11 mL/min to 43 +/- 22 mL/min; nonresponders: 39 +/- 25 mL/min to 32 +/- 21 mL/min). In the responders renal hemodynamics remained stable after lisinopril (renal plasma flow: 223 +/- 80 mL/min to 216 +/- 91 mL/min; filtration fraction: .20 +/- .04 to .20 +/- .05; renal vascular resistance: 386 +/- 179 to 326 +/- 209 units). In the nonresponders, renal plasma flow decreased (228 +/- 141 mL/min to 162 +/- 117 mL/min, P less than 0.005), filtration fraction increased (.19 +/- .08 to .24 +/- .12, P less than 0.05), and renal vascular resistance increased (695 +/- 747 to 1265 +/- 1574 units, P less than 0.05) after chronic lisinopril therapy. We conclude (1) there is a heterogeneous response to lisinopril in patients with chronic renal disease and hypertension, (2) lisinopril monotherapy may result in effective blood pressure control without renal hemodynamic compromise, and (3) an increase in PRA following converting enzyme inhibition may identify those in whom the circulating renin angiotensin system is participating in systemic hypertension and intrarenal hemodynamic changes.

Adult↗
PubMed2001

Alanyl-glutamine dipeptide does not affect hemodynamics despite a greater increase in myocardial heat shock protein 72 immunoreactivity in endotoxemic sheep.

The possible beneficial effect of supplemental glutamine (Gln) in critically ill patients has been suggested to be mediated by the induction of the cytoprotective heat shock proteins (HSP)32 and HSP72. There is evidence that HSP72 and HSP32 have opposite effects on the hemodynamic situation during endotoxemia. Therefore, the effect of Gln supplementation on the cardiovascular system is not clear. We investigated the effect of alanyl-Gln (Ala-Gln) dipeptide on cardiovascular function in healthy and endotoxemic sheep. Ten sheep catheterized for chronic studies received Ala-Gln 700 mg/(kg x d) [equal to 470 mg/(kg x d)Gln] on 4 consecutive days, and 10 sheep received NaCl (9 g/L) as the control solution. On d 4, four sheep of each group were killed and myocardial samples were taken for immunohistochemistry. The remaining sheep received a continuous infusion of endotoxin [Salmonella typhosa, 10 ng/(kg x min)]. Hemodynamic parameters were measured before application of Ala-Gln or the control solution, and during endotoxemia. Myocardial HSP72 immunoreactivity was determined by immunohistochemistry. After 24 h of endotoxemia, the sheep exhibited a hyperdynamic circulation. No difference was found in the hemodynamic parameters between treatment and control group. Ala-Gln treated sheep had a greater increase in myocardial HSP72 immunoreactivity compared with controls after (P < 0.05) but not before endotoxemia. In summary, Ala-Gln increased HSP72 immunoreactivity after endotoxemia, but did not alter hemodynamic parameters. Thus, Ala-Gln supplementation does not seem to aggravate the hyperdynamic circulation in endotoxemic shock.

Animals↗
PubMed2001

Pregnancy and steroid hormones enhance the systemic and regional hemodynamic effects of calcitonin gene-related peptide in rats.

Calcitonin gene-related peptide (CGRP) is a potent vasodilator neuropeptide known to be involved in the regulation of vascular resistance. Several lines of evidence suggest that CGRP plays a role in the vascular adaptations that occur during normal pregnancy; however, the effects of exogenous CGRP on systemic and regional hemodynamics during pregnancy remain unknown. Therefore, the purpose of this study was to determine the hemodynamic effects of systemically administered CGRP in adult pregnant (Day 19) and ovariectomized (ovx) rats using the radioactive microsphere technique. In addition, we also used ovariectomized rats treated for 3 days with estradiol (E2), progesterone (P4), E2 + P4 in sesame oil, or oil only to assess if these hormones regulate the CGRP-induced hemodynamic changes. On the day of study, catheters were inserted into the left cardiac ventricle (through the right carotid artery), right jugular vein, and caudal tail artery. Hemodynamic studies using radioactive microspheres were then performed in conscious rats 3 h after recovery from anesthesia. Blood pressure and heart rate were continuously monitored, and left ventricular pressure was determined immediately prior to each microsphere injection. Microspheres labeled with either (141)Ce or (85)Sr were injected prior to and 2 min following the i.v. bolus injection of CGRP (270 pmol/kg body weight [BW]). Mean arterial pressure (MAP) and total vascular resistance in pregnant rats was lower than in ovx rats, and this was further decreased with an i.v. bolus injection of 270 pmol CGRP/kg BW. Cardiac output was elevated with further increases upon CGRP administration in pregnant but not in ovx rats. The CGRP-induced changes in MAP, total vascular resistance, and cardiac output in E2 + P4 -treated rats were similar to that observed in Day 19 pregnant rats, indicating that CGRP effects on these parameters during pregnancy may be modulated by steroid hormones. Both pregnancy and E2 + P4 treatment in ovx rats caused significant decreases in CGRP-induced resistance in mesenteric, coronary, and renal vasculature. Thus, the vasodilatory sensitivity to CGRP during pregnancy may be mediated through decreased total vascular resistance, particularly to coronary, mesenteric, and renal vascular beds. Thus, CGRP-induced vasodilatory effects may play a role in mediating vascular adaptations that occur during pregnancy and that steroid hormones may modulate these CGRP effects.

Animals↗
PubMed1996

Hemodynamic changes after retroperitoneal CO2 insufflation for posterior retroperitoneoscopic adrenalectomy.

Intraoperative complications and hemodynamic alterations during posterior capnoretroperitoneoscopic adrenalectomy in the prone position were investigated in 16 consecutive patients using invasive hemodynamic monitoring. Under general anesthesia with propofol and fentanyl, hemodynamic changes were made before (M1) and during retroperitoneal CO2 insufflation (15 mm Hg) [M2]; 20 mm Hg [M3]. Retroperitoneal insufflation resulted in a significant increase of cardiac output (+72%), stroke volume (+42%), mean arterial pressure (+39 %), and mean pulmonary arterial pressure (+36%). Although retroperitoneal inflation was accompanied by a significant increase of central venous pressure (+37%), an increase of preload may have lead to higher filling pressures. Heart rate, systemic vascular resistance, and pulmonary vascular resistance did not show significant changes. One pneumothorax and two cutaneous emphysemas occurred. We have demonstrated, in a small number of patients, that retroperitoneal CO2 insufflation for posterior capnoretroperitoneoscopic adrenalectomy in the prone position results in hemodynamic changes without apparent adverse effects.

Adolescent↗
PubMed1996

The hemodynamic and renal effects of sevoflurane and isoflurane in patients with coronary artery disease and chronic hypertension. Sevoflurane Ischemia Study Group.

In patients without significant cardiovascular disease, the hemodynamic effects of sevoflurane and isoflurane are similar; however, the hemodynamic effects of sevoflurane in patients with hypertension and ischemic heart disease are unknown. To examine the effects of sevoflurane in comparison to isoflurane in this high-risk population, 214 patients scheduled for elective surgery were enrolled if they had evidence of ischemic heart disease or multiple risk factors for ischemic heart disease. Patients were randomly assigned to receive sevoflurane (n = 106) or isoflurane (n = 108) for anesthetic maintenance in conjunction with fentanyl and nitrous oxide in oxygen. Deviations in arterial blood pressure or heart rate of more than 20% from preinduction values that persisted after adjustment of the volatile anesthetic concentration were treated with intravenous phenylephrine, ephedrine, nitroglycerin, atropine, or esmolol as needed. Creatinine, blood urea nitrogen (BUN), and urine protein were measured before surgery, immediately after surgery, and 24 and 48 h postoperatively. For analysis, patients were divided into those with and those without the diagnosis of chronic hypertension. Heart rate and arterial blood pressure responses to sevoflurane and isoflurane were not different for the patients with or without chronic hypertension. Neither anesthetic was associated with a more frequent treatment for hemodynamic deviation. After surgery, creatinine and BUN decreased in both the sevoflurane and isoflurane groups without significant differences between groups. The incidence of post-operative proteinuria was similar in the sevoflurane and isoflurane groups. We conclude that hemodynamic stability in patients with hypertension and ischemic heart disease is similar with sevoflurane and isoflurane. No differences in renal function were observed between the sevoflurane and isoflurane groups.

Adult↗
PubMed1996

The effects of triiodothyronine on hemodynamic status and cardiac function in potential heart donors.

Brain death is associated with altered cardiac function and low concentrations of circulating triiodothryronine (T3). However, the effects of T3 administration on hemodynamic status and cardiac function in potential heart donors remain controversial. Thirty-seven brain-dead patients were randomly and blindly allocated to receive an intravenous bolus of either 0.2 microgram/kg T3 (n = 19) or saline placebo (n = 18). Measurements included conventional hemodynamic and echocardiographic variables of cardiac volume conditions and systolic function of the left ventricle (fractional area change [FAC], velocity of myocardial fiber shortening) using a transesophageal probe, arterial and mixed venous blood gas parameters, and serum thyroid hormone concentrations. The mean concentration of T3 was 1.86 +/- 1.55 pmol/L, and only six patients (16%) had normal values of T3 in control conditions. There was no significant correlation between T3 concentration and FAC (R = 0.17, not significant). All patients receiving T3 had normalized serum T3 concentration (7.55 +/- 2.56 pmol/L) in contrast to patients receiving saline (1.48 +/- 1.26 pmol/L). No significant differences in hemodynamic and echocardiographic parameters were observed between the placebo and T3 groups. Indeed, FAC remained unchanged after T3 (44% +/- 17% vs 46% +/- 22%) or placebo (47% +/- 18% vs 50% +/- 14%) administration. In 20 patients with impaired left ventricular function (FAC < 50%), FAC remained unchanged after T3 (n = 10; 34% +/- 12% vs 30% +/- 10%) or placebo (n = 10; 38% +/- 12% vs 35% +/- 13%) administration. In 17 patients in whom organ harvesting was delayed, transesophageal echocardiography was performed 6 h later and no significant changes in FAC were noted in the T3 group (n = 8; 49% +/- 17% vs 44% +/- 17%) and the placebo group (n = 9; 51% +/- 18% vs 47% +/- 18%). In conclusion, T3 administration did not improve hemodynamic status and myocardial function in brain-dead patients, suggesting that the euthyroid sick syndrome is not the main determinant of myocardial dysfunction in these patients.

Adolescent↗