Haemodynamics and body fluid volumes in response to fluid loading in conscious dogs: non-excretory renal influences

1. Twelve conscious, chronically instrumented dogs were subjected to rapid loading with sodium chloride solution (150 mmol/1; saline) before and 1 day after bilateral nephrectomy (six dogs) or ureterocaval anastomosis (six dogs). Measurements were performed up to 3 h after the fluid load and included cardiac output with an electromagnetic flowmeter, mean arterial pressure and right atrial pressure with chronically implanted catheters, interstitial fluid pressure with a plastic capsule, heart rate, extracellular fluid volume, erythrocyte volume, plasma volume, plasma protein concentration and other variables. 2. The increase in cardiac output in response to saline load was significantly prolonged in the anephric dogs compared with those with uretero-caval anastomosis; mean arterial pressure, right atrial pressure and heart-rate changes were similar in both groups. 3. Plasma volume appeared to increase more in the anephric dogs than in those with uretero-caval anastomosis during the first hour after the infusion, although conflicting results were obtained with different estimates of plasma volume changes. Interstitial fluid pressure increased significantly less in the anephric dogs in the early stages of the fluid load. 4. Effective vascular compliance (the ratio of the change in blood volume to the change in right atrial pressure) appeared increased in the anephric dogs. On the other hand, the change in cardiac output for a given change in right atrial pressure was found to increase after bilateral nephrectomy. 5. It is suggested that the prolonged increase in cardiac output observed in anephric dogs was not the consequence of preferential plasma volume expansion nor of decreased venous compliance, but may reflect an alteration in the cardiac function curve.     

Gonadoblastoma: clinicopathologic correlation in six patients

Six patients with a total of nine gonadoblastomas are presented; three--and possibly a fourth--had dysgerminomatous overgrowth which was massive in two patients. Calcification detected by abdominal films was present in three sufficient for preoperative diagnosis. All patients were found to have a Y stem line on peripheral leukocyte chromosome cultures except one patient, who had a 46 XX/45 XO karyotype. She was found to have Y chromatin bodies in the germ cells of her tumor which was in a normal ovary found at exploration for an ectopic pregnancy. Three were found in virilized phenotypic females investigated for amenorrhea, and two for therapy of pelvic masses due to dysgerminomatous overgrowth. Y chromatin studies are reported on gonadal tissue.     

Craig-Scott orthosis: a biochemical and functional evaluation

The Craig-Scott double upright knee ankle orthosis was subjected to a biomechanical evaluation which included analysis of the force interaction with the supported limb and a functional evaluation. The results were compared with data previously determined from biomechanical evaluations of other common orthoses. In the Craig-Scott design, the single application of the knee stabilizing force below the knee concentrates this force in a relatively small bony area, sometimes exceeding tolerance. This might be avoided by using a tibial closure with patellar tendon bearing features. The design was found to produce relatively low anatomic knee shear. In functional aspects such as donning, doffing, transfers and ambulation, the orthosis is essentially equivalent to other double upright designs. The rigidity of the orthosis with only a tibial band closure and a bail connecting the uprights was determined to be adequate. The limited number of bands and closures provides some advantages in reduced donning and doffing time; however, in the absence of posterior closures below the knee, the orthosis had a tendency to slide forward off the leg when transferring. This disadvantage was eliminated by adding a soft posterior closure below the knee, which produced a minimal increase in donning and doffing times.     

Toxicity following methoxyflurane anaesthesia. IV. The role of obesity and the effect of low dose anaesthesia on fluoride metabolism and renal function

Seven obese and five normal weight patients were studied before, during and after one hour of methoxyflurane-nitrous oxide anaesthesia during peripheral surgical operations and compared with eight patients of normal weight anaesthetized with nitrous oxide-meperidine and d-tubocurare. Estimates were made of renal function, including serum and urinary electrolytes, osmolarity, uric acid, urea and creatinine. Renal clearances for the latter three substances were also calculated. Serum and urinary inorganic and organic fluoride concentrations were measured, as were renal clearances. This low dose methoxyflurane anaesthesia resulted only in a decrease in uric acid clearance among all the measures, when compared to the meperidine-nitrous oxide controls. The clearance of uric acid remained depressed for longer in the obese patients, but otherwise they did not differ from the normal weight patients. It is possible but not proven that depressed uric acid clearance may be related to the organic fluoride metabolite and an early indicator of methoxyflurane renal toxicity. The previously documented biotransformation of methoxyflurane was seen in this study. A double peak in serum inorganic fluoride was shown in all patients but one. Rather large differences in peak levels of serum inorganic fluoride occurred. The only significant difference between the obese and normal weight patients as far as fluoride metabolism was concerned was a greater variability in the serum inorganic fluoride levels in the obese patients. It would appear that the obese patient metabolizes methoxyflurane in a quantitatively if not qualitatively different fashion than the normal weight patient, perhaps because of fatty infiltration of the liver. Caution is advised in the use of methoxyflurane for more than 90 minutes of low concentration administration in view of the unpredictability of the biotransformation.     

Cardiovascular and subjective effects of intravenous cocaine administration in humans

Nine volunteer subjects were tested with intravenously administered cocaine hydrochloride in doses ranging from 4 to 32 mg, as well as 10 mg of dextroamphetamine sulfate. Measures of cardiovascular and subjective effects were made. Generally parallel dose-effect functions were obtained for heart rate, blood pressure, Addiction Research Center Inventory scores, Profile of Mood Scales, and subject ratings. A substantial effect on each of these variables was recorded after 8 mg of cocaine. The increase continued and peaked at approximately 16 mg after which it usually leveled off. Ten milligrams of dextroamphetamine generally had an effect comparable to 8 to 16 mg of cocaine.