Adverse outcome with delay in identification of catatonia in elderly patients

All three patients to show catatonia at a teaching veterans' hospital over a 1-year period were over 60 years old. Each experienced delays of 2-5 months in identification of catatonia and adverse events attributable to the delay (e.g., pulmonary embolus, physical restraint, pneumonia, mislabeling as "advanced dementia," Do Not Resuscitate orders, and death). These outcomes suggest that geriatric patients with unrecognized catatonia are at high risk for major adverse events.

Quality of life outcomes of saquinavir, zalcitabine and combination saquinavir plus zalcitabine therapy for adults with advanced HIV infection with CD4 counts between 50 and 300 cells/mm3

BACKGROUND

Benefits in patient health-related quality of life (HRQL) have not yet been demonstrated for combination antiretroviral therapy with protease inhibitors and nucleoside analogues. This double-blind study evaluated zalcitabine or saquinavir monotherapy and combination saquinavir plus zalcitabine therapy on HROL of human immunodeficiency virus (HIV)-infected adults.

METHODS

940 HIV-infected patients (CD4 counts 50-300 cells/mm3) who had discontinued zidovudine therapy (for intolerance or treatment failure) were randomized to one of three regimens: zalcitabine 0.75 mg every 8 h; saquinavir 600 mg every 8 h; or combination zalcitabine 0.75 mg plus saquinavir 600 mg every 8 hours. HRQL was measured at baseline, 24 and 48 weeks using the Medical Outcome Study HIV Health Survey (MOS-HIV). The primary endpoints were the physical and mental health summary scores (PHS; MHS) of the MOS-HIV as well as a global visual analogue scale (VAS) score.

RESULTS

After 24 weeks, the zalcitabine-treated patients demonstrated significantly greater decreases in PHS scores (-4.4 +/- 0.6; saquinavir: -1.3 +/- 0.6; zalcitabine plus saquinavir: -1.7 +/- 0.6; P < 0.0001) and MHS scores (-2.2 +/- 0.5; saquinavir: -1.0 +/- 0.5; zalcitabine plus saquinavir: -0.5 +/- 0.5; P = 0.032) compared to saquinavir and zalcitabine plus saquinavir treated patients. No differences were observed on the VAS (P = 0.172). Nine of 10 MOS-HIV subscales demonstrated results consistent with the primary endpoints. After 48 weeks, a statistically significant difference between the saquinavir-treated groups and the zalcitabine monotherapy group was observed for PHS scores (zalcitabine: -5.8 +/- 0.6; saquinavir: -4.1 +/- 0.6; zalcitabine plus saquinavir: -3.5 +/- 0.6; P = 0.014).

CONCLUSIONS

Saquinavir monotherapy and combination saquinavir plus zalcitabine demonstrated a benefit in HRQL relative to zalcitabine monotherapy in patients with prior zidovudine therapy. The HRQL findings are concordant with improved survival and reduced clinical progression of HIV infection found in this study.

Resuscitation considerations to prevent pressure ulcers in trauma patients

The success of a trauma resuscitation is often measured in short-term patient outcomes. To be a true success, the patient should also be protected from long-term problems that are easily preventable. Skin pressure ulcers are a real threat to trauma patients who are immobilized. Nurses involved in the initial care of these patients should be aware of the common causes of skin breakdown and how to prevent it.

Hypofrontal symptoms from olanzapine: a case report

Olanzapine acutely induced disabling hypofrontal symptoms in a 31-year-old male. This occurred after 13 years of exposure to typical neuroleptics without such symptoms. Presumably, hypofrontal symptoms should limit the dose of atypical neuroleptics in some patients. Milder expressions of hypofrontal symptoms should be more common.

False-Positive Ethylene Glycol Levels in Patients With Diabetic Ketoacidosis

OBJECTIVE

To describe two patients with diabetic ketoacidosis and positive ethylene glycol levels and to call attention to the possibility of a false-positive ethylene glycol determination in patients with ketoacidosis.

METHODS

Clinical manifestations and laboratory tests in the two patients were summarized. Serum specimens for both patients were analyzed for ethylene glycol, serum ketones, glucose, osmolality, pH, and electrolytes.

RESULTS

Respective laboratory findings in our two patients were as follows: serum glucose levels, 56.4 and 45.7 mmol/L; serum acetone, positive in 1:80 and 1:128 dilution; serum osmolality, 366 and 377 mmol/kg; pH, 6.9 and 7.2; and ethylene glycol, 3.46 and 2.45 mmol/L.

CONCLUSION

Neither of these two elderly women had ingested ethylene glycol; nevertheless, both had positive results for ethylene glycol on a blood toxicology screen. Review of the literature demonstrates that false-positive ethylene glycol levels can be detected in patients with ketoacidosis. This information is documented in this report and should alert practicing physicians to such a possibility.

Blood pressure control and erythrocytosis in rats: theory and observations

We compared some of our latest experiments on blood pressure control and erythrocytosis in spontaneously hypertensive rats with Gaar's computer-simulated studies, which suggest that erythrocytosis is a key to understanding the hemodynamic changes in hypertension. We tested two of Gaar's several predictions: (i) peripheral vascular resistance decreases when the feedback control of erythrocytosis is blocked and (ii) in primary hypertension, blood volume is increased slightly. We also studied the interrelation of systolic blood pressure and plasma renin substrate in spontaneously hypertensive rats, and the effect of diet on renin, blood pressure, and erythrocytosis. Our data showed that (i) on a percentage basis the renin system supports blood pressure essentially in the same manner in normal and hypertensive rats, (ii) peripheral vascular resistance decreased when erythrocytosis was partially blocked by feeding a low-iron diet, (iii) blood volume was similar in normal and hypertensive rats, and (iv) dextrin stimulates plasma renin, packed cell volume, and blood pressure in hypertensive rats. We conclude that blood pressure and erythrocytosis are interrelated, that the combined data of stimulated and experimental studies support the notion that primary hypertension is a blood-vessel adaptation in response to a renal energy need that may require additional oxygen.

Unintentional injury death rates in rural Appalachia

Rural unintentional injury (UI) death rates are higher than rates for urban regions. Our trauma center serves 49 rural Appalachian (AP) counties in a 120-county rural state. We investigated the impact of prehospital and hospital resources on UI death rates in our referral area. Age-adjusted and average age- and sex-specific UI death rates from 1979-1985 were compared among 49 rural AP counties, the 71 non-Appalachian (NAP) counties, and the United States. Counties were grouped for comparisons by level of prehospital care (Advanced Life Support [ALS] vs. Basic Life Support [BLS]) and by presence (H) or absence (NH) of a hospital. Death rates were calculated using data from the 1980 population census, the National Center for Health Statistics (NCHS), and state vital statistics. Within AP, all 49 counties have ambulance service. Only 9/49 (18%) have ALS service and 13/49 (26%) have no hospital. Age-specific AP rates were higher than NAP and US rates in the 25-44 and 45-64 year age groups. AP death rates were highest for BLS and NH counties across all age groups. Rural UI death rates in the region remain unacceptably high. The reason(s) that AP death rates exceed the NAP rates is uncertain. ALS service and an available hospital were associated with lower death rates. We propose both educational and epidemiologic programs to better identify and define additional problems.

Concurrent focal segmental glomerulosclerosis and membranous nephropathy

Focal segmental glomerulosclerosis and membranous glomerulonephropathy are two entities that may result in the nephrotic syndrome. Two young women exhibited concurrent focal segmental glomerulosclerosis and focal segmental membranous nephropathy on renal biopsy. Although the lesions were severe, both patients had asymptomatic proteinuria, normal renal function, and a benign clinical course. The concurrence of these glomerulopathies may portend a more benign clinical course than expected for a patient presenting with either lesion alone.

Duration of ECT-induced tachycardia as a measure of seizure length

The duration of ECT-induced tachycardia in 203 seizures of 28 patients was measured. Tachycardia duration was easily determined; it correlated highly with both motor (cuffed arm) and EEG seizure estimates.

Prolactin levels after bilateral and unilateral ECT

Serial post-ictal serum prolactin levels were obtained over a period of one hour after bilateral or unilateral electroconvulsive therapy (ECT) in six patients. Bilateral ECT yielded significantly higher mean post-ictal prolactin levels than unilateral ECT at the 15, 20, 30 and 60 minute sampling times. These findings demonstrate a greater hypothalamic-stimulating effect of bilateral than unilateral ECT, and may explain the reported therapeutic advantage of bilateral over unilateral ECT in the treatment of patients with melancholia.

Predicting success of intensive dialysis in the treatment of uremic pericarditis

To identify predictors of the success or failure of daily intensive dialysis in uremic pericarditis, a retrospective examination was made of initial clinical, laboratory, and echocardiographic data in 97 patients using univariate and multivariate statistical analysis. In this group, 67 patients showed response to intensive dialysis, and 30 patients did not (22 required surgery and eight died). By univariate analysis, nine factors correlated with intensive dialysis failure (p less than 0.10): admission temperature over 102 degrees F, rales, admission blood pressure under 100 mm Hg, jugular venous distension, peritoneal dialysis treatment only because of severe hemodynamic instability, white blood cell count over 15,000/mm3, white blood cell count left shift, large effusion by echocardiography, and both anterior and posterior effusion by echocardiography. Echocardiographic left ventricular size and function were not useful predictors of success or failure; there was no difference in response to hemodialysis in patients with pericarditis before dialysis (69 percent) versus patients with pericarditis during a maintenance program (67 percent). By discriminant analysis, a seven-variable function was constructed that divided the patients into three groups: (1) those likely to show response to intensive dialysis (48 patients, predictive value of 98 percent), (2) those with an intermediate (38 percent) chance of showing response to intensive dialysis (30 patients), and (3) those unlikely to show response to intensive dialysis (14 patients, predictive value of 100 percent). When the function was applied prospectively to 12 patients (eight with success and four with failure), all were classified correctly. Thus, discriminant analysis of patients with uremic pericarditis allows improved selection of patients with uremic pericarditis likely to have response to daily intensive dialysis and early consideration of alternative forms of treatment in patients unlikely to show response to intensive dialysis. However, the model should be validated in the particular institution where it is to be used before its application.

Reversible nephrotic range proteinuria with renal artery stenosis: a clinical example of renin-associated proteinuria

Nephrotic range proteinuria occurred in a 60-year-old woman with renal artery stenosis and marked hyperreninemia. Treatment by nephrectomy produced resolution of both proteinuria and hypertension. The gradual resolution of the proteinuria postoperatively suggested the proteinuria, at least in part, came from the contralateral kidney. Foot process fusion in the nephrectomy specimen suggested it too was a source of proteinuria. A marked degree of hyperreninemia, as was present in this case, may be necessary before massive proteinuria occurs in renal artery stenosis.

Managing desperate emotional behaviour with hypnosis

When no other psychotherapy or pharmacotherapy could prevent debilitation or institutionalization consequent to longstanding frequent repeated maladaptive behaviour, hypnosis has been observed to be effective in suitable patients. A documentation, three cases of such chronic severe behaviour which have been encountered by the author are described; each had been regarded as hopelessly unmanageable by the primary physician at the time of referral for hypnotherapy. Relevant to their suitability for hypnosis, all three patients were able to understand normal speech with difficulty, were able to concentrate well, and were agreeable to using hypnosis.

Body fluid volumes in the spontaneously hypertensive rat

1. Plasma volume, packed cell volume (PCV), blood pressure, extracellular fluid volume (ECFV) and evans blue disappearance rate were measured in conscious spontaneously hypertensive rats and in weight-matched Wistar normotensive rats. 2. Over the weight range studied (250-350 g), plasma and blood volumes were significantly lower in the spontaneously hypertensive rat. Extracellular fluid volumes were similar in the two groups. PCV and Evans blue disappearance rates were significantly higher in the spontaneously hypertensive rat. 3. Negative correlations were obtained between plasma volume and mean arterial pressure and between the plasma/interstitial fluid volume ratio and mean arterial pressure. 4. The normal extracellular fluid volume and the lack of correlation with mean arterial pressure excludes volume expansion as a pressor mechanism during the established phase of hypertension in the spontaneously hypertensive rat.

Haemodynamics of stable renal transplant recipients

1. Haemodynamics, blood volume, plasma renin concentration and creatinine clearance were evaluated in 24 stable renal transplant recipients. 2. The mean cardiac index of the transplant recipients was not different from that of the normal subjects. 3. The transplant recipients comprised eight hypertensive and 16 normotensive patients. The mean cardiac index was the same in eight hypertensive and 16 normotensive patients. Thus the hypertension of stable renal transplant recipients is sustained by a high total peripheral resistance. 4. The mean blood volume, plasma renin concentration and creatinine clearance were similar in eight hypertensive and 16 normotensive patients. Therefore the hypertension of stable renal transplant recipients is not related to blood volume expansion, elevated peripheral renin or low creatinine clearance. The cause of the elevated total peripheral resistance in hypertension in stable renal transplant recipients remains to be elucidated.

Interrelation of the renin system and erythropoietin in rats

Evidence is presented implicating the renin-angiotensin system in the regulation of plasma erythropoietin concentration. Male and female rats were exposed to hypoxia at 0.43 atm for 8 hr. In male rats, individual erythropoietin values showed a positive correlation with renin, renin substrate, and angiotensin I after 8 hr of hypoxia. In female rats, renin was not elevated during hypoxia. However, after renin was injected subcutaneously, plasma renin values became similar to those in male rats and erythropoietin doubled. Individual erythropoietin values of the combined groups showed a positive correlation with plasma renin. A single oral dose of SQ 14225, an angiotensin I-converting enzyme inhibitor, reduced erythropoietin to undetectable levels in renin-injected female rats. Angiotensin II, in subpressor amounts, prevented the suppression of erythropoietin by SQ 14225. SQ 14225 also reduced renin substrate concentration at ambient pressure and during hypoxic exposure. The correlation coefficient between renin substrate and erythropoietin in rats given SQ 14225 to lower substrate or angiotensin II to increase substrate was 0.85; p < 0.0005. The increase in renin substrate that occurred during hypoxia in female rats given angiotensin II correlated positively with erythropoietin, r = 0.86; p < 0.0005.

Sequential hemodynamic changes in end-stage renal disease and the anephric state during volume expansion

The sequence of hemodynamic events during periods of salt- and water-loading was studied in anephric patients and those with end-stage kidney disease. The 10 patients studied showed four different sequential hemodynamic patterns: 1) no significant increase in blood pressure (BP) in two patients; 2) increase in BP associated with an increase in cardiac output and without change in total peripheral resistance in two patients; 3) increase in BP associated with an increase in total peripheral resistance from the beginning without an increase in cardiac output in five patients; and 4) increase in BP associated with an initial increase in cardiac output followed by an increase in total peripheral resistance in one patient. There was a significant positive correlation between BP and blood volume and between BP and total exchangeable sodium in the patients in whom salt- and water-loading increased the BP. It is concluded that during salt- and water-loading an initial rise in cardiac output is not necessary to increase BP and that a sustained rise in cardiac output does not always increase the total peripheral resistance. Mechanisms other than whole-body autoregulation play a role in increasing BP during salt- and water-loading in patients deprived of renal excretory function.

Clinically occult diffuse proliferative lupus nephritis. An age-related phenomenon

Thirteen patients with systemic lupus erythematosus (SLE) who had normal results of urinalysis, absence of proteinuria, and normal serum creatinine values underwent renal biopsy. Three of 13 patients had diffuse proliferative glomerulonephritis (group 1). Biopsy specimens showed segmental fibrinoid necrosis, diffuse mesangial hypercellularity, and substantial immunoglobulin deposition. Group 2 comprised those patients whose histologic findings did not portend a poor prognosis. Four had mesangial proliferative glomerulonephritis, three had focal proliferative glomerulonephritis, and three had minimal mesangial widening. The values of inulin clearance in group 1 did not differ significantly from those in group 2. Patients in group 1 had a mean age of 19 years, a value significantly lower than in group 2 (41.8 years). Review of previous reports also supports the thesis that this phenomenon is age related. Our study underscores the importance of renal biopsy in patients with SLE despite the absence of clinical evidence of renal involvement, particularly in patients under 30 years of age.

Neurogenic activity--angiotensin II interaction during the development and maintenance of renal hypertension in the rat

1. Pentolinium tartrate (a ganglionic blocker) was injected in conscious rats during the early and late phases of two-kidney renal hypertension produced by aortic ligation. 2. In the early phase ( 5 days after aortic ligation), ganglionic blockade resulted in a decrease in blood pressure equal to that obtained in normotensive rats. Later, at days 12 and 40, for equally severe hypertension, ganglion blockade resulted in a greater decrease in blood pressure. 3. A 30 min infusion of [Sar1, Ala8]angiotensin II during the pentolinium-induced nadir in blood pressure resulted in a further decrease in blood pressure at day 5. Later, at days 12 and 40, this effect was smaller. 4. A 300 min infusion of [Sar1, Ala8]angiotensin II normalized the blood pressure in hypertensive rats at day 40. This delay response may be secondary to a central effect of the antagonist, reducing neurogenic tone or peripheral antagonism of locally generated angiotensin II in the blood vessel walls. 5. At day 40, removal of the small left kidney resulted in a greater decrease in blood pressure. This suggests the presence of a renal factor other than renin in the chronic phase of this hypertension.

Glomerular lesions in benign essential hypertension. A study of eight biopsy specimens with laboratory evidence suggestive of glomerular abnormalities

We performed renal biopsies on eight patients who had benign essential hypertension but laboratory abnormalities suggestive of glomerulonephritis. Persistent microscopic hematuria was detected in four patients, proteinuria in five, RBC casts in two, and decreased glomerular filtration in seven. In all eight biopsy specimens, we detected hyaline arterionephrosclerosis, focal glomerular obsolescence, and segmental, afibrillar thickening of glomerular basement membranes. Direct immunofluorescence studies performed on all eight samples were negative for immunoglobulins, complement, and fibrinogen. Although the patients in our study had laboratory findings suggestive of glomerulonephritis, the morphologic changes were indicative of benign essential hypertension.

Long-term clinical effects, bioavailability, and kinetics of minoxidil in relation to renal function

Minoxidil was used to treat 26 patients (17 to 67 years old) with severe hypertension and varying degrees of renal function. Our object was to assess long-term clinical efficacy, kinetics (acute and chronic), and bioavailability of minoxidil in chronic renal insufficiency. Minoxidil, 27 to 30 mg per day, decreased systolic and diastolic blood pressure during the first three months of therapy. Between the third and 24th months (30 months in one patient) there was no further change. Propranolol or clonidine was needed to control heart rate, and furosemide or dialysis was needed to control edema induced by minoxidil. Renal function improved in some of the mildy azotemic patients. Minoxidil kinetics after the customary dose did not differ whether the drug was taken as tablet or solution. Kinetic parameters during chronic administration of minoxidil did not differ from those after acute administration. The kinetics in chronic renal insufficiency do not differ from these in subjects with normal renal function.

Effect of administration of Sar1-Ala8-angiotensin II during the development and maintenance of renal hypertension in the rat

1. Sar1-Ala8-Angiotensin II (an angiotensin antagonist) was infused in rats during the development and maintenance of renal hypertension produced by aortic ligation between renal arteries. 2. In the early phase (5 and 12 days after ligation), infusion of the antagonist markedly decreased blood pressure although it did not reach normal pressures. Later (day 40) only a modest decrease in blood pressure was noted. 3. Removal of the small left kidney always decreased the blood pressure to normal pressures. 4. It is concluded that the renin-angiotensin system is the major pressor component in the initiation of this hypertension. Later, other factors of renal origin assume a pressor function.

Effect of propranolol on blood pressure and renin in renal hypertension in the rat

1. Propranolol was administered to groups of mature rats before and during the development of renal hypertension induced by ligation of the aorta between the renal arteries. 2. At a dose 10 mumol (3 mg) of propranolol/kg, administered by intraperitoneal injection, the onset and severity of hypertension were not affected, although plasma renin concentration was significantly lower than in the untreated hypertensive rats in the first 5 days after the operation. 3. With 200 mumol (60 mg) of propranolol/kg, administered in the drinking water, peak blood pressure 5 days after aortic ligation was lower than in the untreated control rats, but plasma renin concentration was no lower than with the smaller dose. 4. The development of severe hypertension despite reduction in plasma renin concentration on the low dose of propranolol suggests the participation of renal vasopressor factors other than renin in this model. 5. A higher dose of propranolol reduced the rise in plasma concentration to an equal extent but the rise of blood pressure at 5 days was also reduced, which supports this concept.

The haemodynamic response to salt and water loading in patients with end-stage renal disease and anephric man

1. Patients with end-stage renal disease and anephric patients underwent expansion and depletion of body fluids with salt and water. This resulted in four different sequential haemodynamic patterns: (i) no significant increase in blood pressure; (ii) increase in blood pressure associated with a rise in cardiac output and no effect on total peripheral resistance; (iii) increase in cardiac output followed by a rise in blood pressure and total peripheral resistance; (iv) increase in total peripheral resistance and blood pressure without significant changes in cardiac output. 2. It is concluded that an initial rise in cardiac output is not necessary to increase-blood pressure in either anephric man or patients with end-stage renaldisease.

Salt, frusemide and renin in severe experimental renal hypertension

1. Sodium-deficient diet failed to alter development and maintenance of severe renal hypertension produced in the rat by ligation of the aorta between the renal arteries. 2. High sodium diet did not alter the early phase of this hypertension, but significantly decreased blood pressure elevation in the late phases. 3. The decrease in blood pressure produced by high sodium intake does not appear to be mediated by renin suppression. 4. Frusemide effectively reduced blood pressure and renin at all phases.

The interrelation of renin and iron binding capacity

When rats are subjected to hypoxia, an increase in serum angiotensinogen concentration occurs which is accompanied by the appearance of serum erythropoietin (EP) during the first 24 h. Subsequent increases in EP reach maximum values 24 to 48 h after increases in packed cell volume (PCV) and serum renin levels. The current experiments were designed to determine if a decrease in iron stores is the stimulus for renin production when rats are rapidly expanding their red cell volume in a hypoxic environment. Young rats fed McCall's low iron diet were paired with rats fed the same diet supplemented with ferric citrate (6 g/kg diet). After two weeks at ambient pressure, they were subjected to hypoxia (0.48 atm) for 1 to 10 days. After 5 days at the reduced pressure, a fraction of the rats on the low iron diet were fed the iron-supplemented diet. At the time of sacrifice, serum was assayed for total iron binding capacity (TIBC) and renin. Rats that were fed the low iron diet showed an increase in TIBC, an increase in serum renin and a positive correlation between serum renin and TIBC. Rats that were fed a normal iron diet under the same conditions had lower TIBC, lower serum renin and no correlation between serum renin and TIBC. When low iron diet rats were supplemented with iron, TIBC and serum renin decreased. These experiments may have a clinical counterpart. The total iron binding capacity, renin and angiotensinogen were measured in the serum of women during the first 19 weeks of pregnancy. Women during early pregnancy showed an increase in TIBC, an increase of renin and angiotensinogen in the serum and a positive correlation between TIBC and renin concentration. It is suggested that the increased concentration of renin in the serum of women during the first 19 weeks of pregnancy and in the serum of rats that are rapidly expanding their red cell volume are related to a decrease in iron stores.

Experimental model of severe renal hypertension

A simple technique is described for producing severe reproducible renal hypertension in the rat. Total ligation of the aorta between the renal arteries and just below the origin of the superior mesenteric artery resulted in sustained systolic and diastolic pressures in 90 per cent of 170 rats studied. Arterial pressure is then measured in the conscious unrestrained rat through a carotid cannula inserted no more than 48 hours before measurements are made. The mean arterial pressure increases to a peak of 180 mm. Hg at day 5 and then remains at a plateau of 160 mm. Hg through the 40 days of the study. Plasma renin increases to a peak at 5 days but returns to baseline at 30 days despite the persistence of severe hypertension. Infarction of the left kidney below the aortic constriction results in no increase in pressure or plasma renin. Infarctions of the right kidney by emboli originating from the indwelling carotid cannula are associated with greater increases in blood pressure and plasma renin than the standard preparation. Prolonged carotid cannulation must be avoided in order to prevent such emboli. This simple technique for producing renal hypertension allows studies on the pathogenesis of hypertension with an excellent degree of reproducibility and reliability.

A three-phase clinical evaluation of prazosin

A preliminary study of cardiac hemodynamics with measurement in both supine and tilt positions showed that the antihypertensive effect of prazosin given intravenously is associated with a fall in total peripheral resistance, with minor effects on cardiac output and heart rate, and with no consistent orthostatic hypotension. The postural reflexes appear to remain intact. The results are entirely similar to those reported by Lund-Johansen. In a second, short-term study of ambulatory patients, prazosin alone exerted an antihypertensive effect somewhat less than that of methyldopa, but the difference in blood pressure reduction between supine and standing positions was less with prazosin than with methyldopa. Both drugs were well tolerated. In a third, long-term study, prazosin alone gave satisfactory antihypertensive results, and prazosin used in combination with polythiazide produced a satisfactory response in 80% of the patients.

Blood pressure regulation in end-stage renal disease and anephric man

The hemodynamic pattern of response to bilateral nephrectomy was studied in 29 patients with end-stage renal disease on maintenance hemodialysis. Four patterns of hemodynamic response were seen. In 12 patients with nonmalignant hypertension, bilateral nephrectomy reduced blood pressure and total peripheral resistance with no effects on cardiac output. In 5 patients with malignant hypertension, bilateral nephrectomy reduced blood pressure, increased cardiac index, and reduced total peripheral resistance more markedly. In these two groups, at equivalent levels of total exchangeable sodium, before and after bilateral nephrectomy, mean arterial pressure and total peripheral resistance were invaribly lower in the absence of renal tissue. In 3 additional patients with nonmalignant hypertension, the decrease in blood pressure after bilateral nephrectomy was delayed from 3 to 12 weeks. When this occurred spontaneously, it was accompanied by a decrease in total peripheral resistance. The fourth hemodynamic pattern was seen in 6 normotensive patients with end-stage renal disease. After bilateral nephrectomy, there were no significant changes in mean arterial pressure, total peripheral resistance, or cardiac output. Salt and water loading failed to elevate blood pressure significantly. Renal transplantation was performed in 3 hypertensive patients before removal of the end-stage kidney. The functioning renal homograft did not result in normal blood pressure as long as the end-stage kidneys remained in place. Removal of the end-stage kidneys significantly decreased mean arterial pressure and total peripheral resistance. In the anephric state, a sharp difference was seen in blood pressure response to salt and water loading between previously normotensive and previously hypertensive patients. Previously hypertensive patients responded with a progressive increase in blood pressure that reached hypertensive levels. Previously normotensive patients failed to elevate their blood pressure significantly. It is concluded that the vasopressor function of the kidney is the most important factor in the pathophysiology of hypertension of end-state renal disease. Expansion of body fluid plays a role, but elevates the blood pressure only in patients who were previously hypertensive. The antihypertensive function of the kidney does not appear to be a major factor in the regulation of blood pressure in end-stage renal disease.