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Background: Changes in blood volume during acute normovolemic hemodilution (ANH) and their consequences for the perioperative period have not been investigated sufficiently., Methods: In 15 patients undergoing radical hysterectomy, preoperative ANH to a hematocrit of 24% was performed using 5% albumin solution. Intraoperatively, saline 0.9% solution was used for volume substitution, and intraoperative retransfusion was started at a hematocrit of 20%. Plasma volume (indocyanine green dilution technique), hematocrit, and plasma protein concentration were measured before and after ANH, before retransfusion, and postoperatively. Red cell volume (labeling erythrocytes with fluorescein) was determined before and after ANH and postoperatively., Results: Mean normal plasma volumes (1,514 +/- 143 ml/m2) and reduced red cell volumes (707 +/- 79 ml/m2) were measured preoperatively. Blood (1,150 +/- 196 ml) was removed and replaced with 1,333 +/- 204 ml of colloid. Blood volume before and after ANH was equal and amounted to 3,740 ml. Intraoperatively, plasma volume did not increase until retransfusion despite infusing 3,389 +/- 1,021 ml of crystalloid (corrected for urine output) to compensate for an estimated surgical blood loss of 727 +/- 726 mi. Postoperatively, after retransfusion of all autologous blood, blood volume was 255 +/- 424 ml higher than preoperatively before ANH. Despite mean calculated blood loss of 1,256 +/- 892 ml, only one patient received allogeneic blood., Conclusions: During ANH, normovolemia was exactly maintained. After surgical blood loss of 1,256 +/- 892 ml, crystalloid and colloid supplies of 5,752 +/- 1,462 ml and 1,667 +/- 548 ml, respectively, and complete intraoperative retransfusions of autologous blood in every patient, mean blood volume was 250 ml higher than preoperatively before ANH.

Background: Changes in acid-base balance caused by infusion of a 0.9% saline solution during anesthesia and surgery are poorly characterized. Therefore, the authors evaluated these phenomena in a dose-response study., Methods: Two groups of 12 patients each who were undergoing major intraabdominal gynecologic surgery were assigned randomly to receive 0.9% saline or lactated Ringer's solution in a dosage of 30 ml x kg(-1) x h(-1). The pH, arterial carbon dioxide tension, and serum concentrations of sodium, potassium, chloride, lactate, and total protein were measured in 30-min intervals. The serum bicarbonate concentration was calculated using the Henderson-Hasselbalch equation and also using the Stewart approach from the strong ion difference and the amount of weak plasma acid. The strong ion difference was calculated as serum sodium + serum potassium - serum chloride - serum lactate. The amount of weak plasma acid was calculated as the serum total protein concentration in g/dl x 2.43., Results: Infusion of 0.9% saline, but not lactated Ringer's solution, caused a metabolic acidosis with hyperchloremia and a concomitant decrease in the strong ion difference. Calculating the serum bicarbonate concentration using the Henderson-Hasselbalch equation or the Stewart approach produced equivalent results., Conclusions: Infusion of approximately 30 ml x kg(-1) x h(-1) saline during anesthesia and surgery inevitably leads to metabolic acidosis, which is not observed after administration of lactated Ringer's solution. The acidosis is associated with hyperchloremia.

Unlabelled: We measured red cell volume (RCV) with the nonradioactive marker sodium fluorescein (SoF) in 30 patients undergoing gynecological operations. Sixteen patients underwent preoperative isovolemic hemodilution (PIHD). RCV measurements were performed before and after PIHD and at the end of the operation. All RCVs were related to corresponding hematocrit (hct) levels. We report a simplified method for its clinical application by reducing the number of blood samples required. To validate our method, we compared RCV within the PIHD bags (bag RCV) with the difference of the patients' RCV before and after PIHD. Bag RCV obtained during PIHD (mean 399+/-81 mL) was measured with a precision of 4.2% by using SoF. There was a significant difference (mean 286+/-401 mL; P < 0.05) between intraoperatively estimated and measured blood loss. The blood loss tended to be underestimated and, in some cases, was underestimated or overestimated substantially. Preoperative and postoperative hct values only offered an imprecise estimation of the patients' RCV. We conclude that RCV measurement using SoF is a precise method for monitoring changes in RCV during PIHD and surgical operation., Implications: We measured red cell volume changes of 30 patients with the nonradioactive marker sodium fluorescein before and after hemodilution and postoperatively with a high precision. We frequently found large differences between intraoperatively estimated and measured blood loss. Preoperative hematocrit values offered an imprecise estimation of the patients' red cell volume.

The occurrence of migraine in women is influenced by hormonal changes throughout the lifecycle. A beneficial effect of pregnancy on migraine, mainly during the last 2 trimesters, has been observed in 55 to 90% of women who are pregnant, irrespective of the type of migraine. A higher percentage of women with menstrual migraine find that their condition improves when they are pregnant. However, in rare cases migraine may appear for the first time during pregnancy. The positive effects of pregnancy on migraine and the possible worsening post partum are probably related to the uniformly high and stable estrogen levels during pregnancy and the rapid fall-off thereafter. Nondrug therapies (relaxation, sleep, massage, ice packs, biofeedback) should be tried first to treat migraine in women who are pregnant. For treatment of acute migraine attacks 1000 mg of paracetamol (acetaminophen) preferably as a suppository is considered the first choice drug treatment. The risks associated with use of aspirin (acetylsalicylic acid) and ibuprofen are considered to be small when the agents are taken episodically and if they are avoided during the last trimester of pregnancy. The 'triptans' (sumatriptan, zolmitriptan, naratriptan), dihydroergotamine and ergotamine tartrate are contraindicated in women who are pregnant. Prochlorperazine for treatment of nausea is unlikely to be harmful during pregnancy. Metoclopramide is probably acceptable to use during the second and third trimester. Prophylactic treatment is rarely indicated and the only agents that can be given during pregnancy are the beta-blockers metoprolol and propranolol.

Background: [corrected] Clinical experience in patients with ovarian cancer has shown special difficulties in maintaining cardiovascular stability during surgery., Methods: To evaluate the causes for this observation, 15 patients with benign ovarian tumours (group I) and 13 patients with ovarian cancer (group II) were investigated perioperatively. Plasma volume (indocyanine green-dilution technique), haematocrit, plasma protein concentration, mean arterial pressure, heart rate, and central venous pressure were measured immediately before and after cytoreductive surgery., Results: Normal values of blood-, plasma-, and red cell volume were determined preoperatively in both groups, and in relation to body surface area there were no intergroup differences of these parameters. In group I, the significant decrease in red cell volume of 313 ml postoperatively was compensated for by an increase in plasma volume of 371 ml (median values). In contrast to group I, the decrease in red cell volume of 328 ml in group II was not related to a significant increase in plasma volume, so that blood volume postoperatively was 483 ml lower than preoperatively, although the same standardized infusion regimen as in group I was applied. Patients of group II had a significantly higher loss of intravascular protein (49 g vs 13 g in group I), which left the intravascular space by another way than by surgical bleeding. This extra protein loss is termed Intraoperative Protein Shift (IPS)., Conclusion: IPS could be an important quantity in perioperative fluid balance. We assume that different surgical procedures predispose to occurrence of differing amounts of IPS.

Hope is the sum of goal thoughts as tapped by pathways and agency. Pathways reflect the perceived capability to produce goal routes; agency reflects the perception that one can initiate action along these pathways. Using trait and state hope scales, studies explored hope in college student athletes. In Study 1, male and female athletes were higher in trait hope than nonathletes; moreover, hope significantly predicted semester grade averages beyond cumulative grade point average and overall self-worth. In Study 2, with female cross-country athletes, trait hope predicted athletic outcomes; further, weekly state hope tended to predict athletic outcomes beyond dispositional hope, training, and self-esteem, confidence, and mood. In Study 3, with female track athletes, dispositional hope significantly predicted athletic outcomes beyond variance related to athletic abilities and affectivity; moreover, athletes had higher hope than nonathletes.

In a retrospective survey performed in Germany and Switzerland, 207 patients (ranging in age from newborn to 70 years) were evaluated in order to establish the frequency, prognosis and diagnostic awareness of kidney involvement in the tuberous sclerosis complex. Renal manifestations were observed in 48% of patients: renal cysts (33 patients), renal angiomyolipoma (AML) (30 patients), a combination of both (8 patients), renal cell carcinoma (3 patients), life-threatening events such as haemorrhage (4 patients), hypertensive crisis (2 patients) and chronic renal failure (10 patients) were also documented. The diagnostic imaging techniques of ultrasonography, intravenous urography, computed tomography and magnetic resonance imaging (MRI) are important but do not always yield definitive information. Differentiation between AML and cysts can be achieved using special MRI techniques (RARE). The potential for renal involvement should be monitored in all patients with the tuberous sclerosis complex.

An unexpected acceleration in elongation of Avena coleoptile segments has been observed with a position sensor transducer 2 to 2.5 h after excision when the segments are immersed in 5 mM succinate buffer (pH 6). The cause of the accelerated growth is unknown.

The effects of cyclic adenosine 3':5'-monophosphate (cAMP) on the growth of Avena coleoptile segments over 4 to 10 hours were monitored with a position sensing transducer. At pH 6, cAMP (0.1 mm with and without 2.5 mm glucose; or 2 mm alone) or dibutyryl cAMP (0.1 mm) was added at the beginning of the experiment, or after about 1 hour or after about 6 or 7 hours. Under all conditions tested, cAMP compounds had little or no effect on coleoptile segment elongation. Inasmuch as cAMP does not duplicate the rapid and vigorous elongation obtained with 2 mum auxin, the hypothesis that cAMP is a mediator of auxin activity is not supported by experimental evidence in this system. This conclusion is dependent upon the assumption that the cAMP compounds penetrated the tissue.

The comparative effects of metabolic inhibitors on acid- and auxininduced growth in oat (Avena sativa L. var. Victory) coleoptile segments have been examined. Acid (pH 4)-induced growth in both peeled and unpeeled segments is inhibited by 1 millimolar KCN when added at the time of acidification. KCN inhibits total acid-induced growth by 59 and 76%, respectively, in peeled and nonpeeled segments during the first 60 minutes. The growth rate of cyanide-treated tissue drops to zero or near zero in both peeled and nonpeeled segments during this period. Cyanide inhibition of total acid-induced growth in peeled segments at pH 5 is even more severe, amounting to about 80% during the first 60 minutes. The possibility that inhibition by cyanide may be caused by some nonspecific effect of the inhibitor on a process other than respiration, e.g. turgor reduction due to membrane damage, has not been ruled out. Acid-induced growth is also inhibited by 3 millimolar sodium fluoride and by anoxia. In unpeeled segments total pH 4-induced growth is inhibited 73% by sodium fluoride and 38% by anoxia during the 1st hour. Possible corrections to the above inhibition percentages which may be necessary due to the sensitivity of basal growth to inhibitors are discussed. Cyanide was found to inhibit auxin-induced growth much more rapidly than acid-induced growth. These data suggest that acid growth may be dependent on respiratory metabolism but to a lesser degree than is auxin-induced growth. If the acid growth theory of auxin action is correct, it appears that there may be two steps in the growth process which are dependent on respiratory metabolism: (a) auxin-induced proton pumping which is highly sensitive to respiratory inhibitors; and (b) acid-mediated wall loosening which is moderately and perhaps indirectly sensitive to respiratory inhibitors.

The effects of cordycepin (3'-deoxyadenosine), an RNA synthesis inhibitor, on auxin-induced elongation in Avena coleoptile segments were studied with a position-sensing transducer. Cordycepin rapidly inhibited auxin-stimulated growth in the coleoptile segments whether added before, at the same time as, or after, the 2 mum auxin treatment. Midcourse additions of 100, 50, and 25 mug/ml cordycepin inhibited auxin-promoted elongation in an average of 18, 22, and 35 minutes, respectively. Additions of cordycepin before or at the same time as the auxin treatment partially inhibited the magnitude of the subsequent auxin-promoted growth but did not appreciably alter the latent period of the auxin response. It was concluded that if cordycepin is inhibiting the synthesis of RNA required for growth, the decay time for this RNA may be considerably shorter than that suggested in the literature from actinomycin D experiments. Preliminary kinetic evidence indicated that cordycepin does not inhibit auxin-induced elongation by acting as a respiratory inhibitor. Studies in mung bean shoot mitochondria demonstrated that cordycepin has no effect on respiration, respiratory control, or ADP/oxygen ratios.

An angular position-sensing transducer was used to make continuous measurements of acid-induced elongation of Avena sativa coleoptile segments. Elongation rates at pH 4.5 (5 mm succinate buffer) were about 5-fold greater than those at pH 6.0. Buffered 0.1 mm abscisic acid produced a partial decrease of the growth rate. Pretreatments with abscisic acid buffered at pH 6.0 usually caused a further reduction of the elongation response when the coleoptile segments were subsequently placed in buffer at pH 4.5 containing abscisic acid. Abscisic acid did not completely prevent the pH effect in any of these experiments, and the brief latent period of the pH response was not affected by abscisic acid treatments. At pH 4.5, where the inhibitory effect of ABA was maximum, low pH-induced elongation was also inhibited by KCN and HgCl(2). These results suggest that pH-(4.5) induced elongation in this system may be dependent on some metabolic processes and that abscisic acid-induced inhibition of this elongation may involve an interaction with these processes.

An angular position sensing transducer was used to make continuous measurements of elongation of a column of Avena sativa coleoptile segments. Elongation stimulated by 2 mum indoleacetic acid was inhibited by 0.1 mm abscisic acid with a latent period of about 4 or 5 minutes at pH 6.0, 30 C. Full growth inhibition was not established until about 1 hour after the addition of the abscisic acid. The same degree of final growth inhibition could be obtained under the above conditions using 10 muM and 1 muM abscisic acid, but the latent period was longer. Pretreatments with abscisic acid affected the growth rate but did not extend the latent period of a subsequent response to auxin. The short term kinetics of inhibition by abscisic acid were not similar to those of any of the inhibitors of RNA and protein synthesis tested in this system.