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PubMed1979

Blood and blood substitutes: current practice.

We have seen that the vast majority of previously healthy patients can tolerate a significant reduction in red cell mass without adverse effect on oxygen consumption. For these patients, volume replenishment with electrolyte solutions will adequately restore blood volume and cardiac output. Colloid solutions offer no advantage over electrolyte solutions, certainly are more expensive and may even be harmful. For patients who need restoration of oxygen-carrying capacity, washed, packed red cell administration is the therapy of choice, and frozen, thawed red cells represent optimal utilization of a scarce commodity. Other components, such as fresh frozen plasma, factor VIII or IX concentrates and platelets, are not indicated unless a specific deficiency exists. Autologous blood, using one of the techniques described above, is a safe and effective means of replacing lost red cells in special circumstances. The use of these techniques, combined with realistic ordering of homologous blood for elective surgical procedures, should act in concert to relieve shortages of blood.

Albumins↗
PubMed1985

[Effects of reduction of blood viscosity at constant hematocrit on the cerebral blood flow].

It is well established that cerebral blood flow (CBF) is low in patients with high hematocrit and is high in anemic patients. An inverse relationship between CBF and hematocrit has been found. Furthermore, if hematocrit is reduced, CBF increases. There is some debate as to whether these observations are due to viscosity or to oxygen carrying capacity of the blood. In order to further elucidate this problem, CBF, blood viscosity and hematocrit were measured in 4 patients with paraproteinemias before and after paraproteins had been removed by plasmapheresis without changes in hematocrit. After plasmapheresis, blood viscosity significantly decreases and CBF increases by a mean of 24.4 ml/100 g/min. Mean arterial blood pressure and hematocrit were not influenced by plasmapheresis. These results indicate that blood viscosity is an important factor in determining CBF. This does not exclude the role of oxygen transport as an associated factor, but it is evident that oxygen transport and blood viscosity are independent variables in the control of CBF.

Blood Viscosity↗
PubMed1985

Increased bone calcium following endurance exercise in the mature female rat.

In order to determine the effects of exercise on the calcium status of selected axial and appendicular bones of mature rats, female Sprague-Dawley rats (8-9 mo.) were divided into three groups including, two months (E2, n = 8) or four months (E4, n = 9) of exercise, and four month sedentary controls (S, n = 10). Exercise consisted of treadmill running for 1 hr/day, 5 days/wk at a speed of 14.1 m/min and 8 degrees elevation. After sacrifice all femurs, tibia/fibula complexes, ribs (T7), and vertebrae (T7) were excised, cleaned, weighed and measured for length and volume. After freeze-drying and bone hydrolysis in 5N HCl, total bone calcium contents and concentrations were determined spectrophotometrically. The acid soluble, appendicular bone calcium contents of the E4 group were significantly greater than S for the femur and tibia respectively: E4 = 159.78 +/- 3.44 mg (mean +/- SEM), 129.46 +/- 4.87 mg; S = 140.03 +/- 5.04 mg, 110.40 +/- 4.71 mg. Bone calcium concentration (mg/g dry bone) also was significantly greater in the tibia/fibulas, ribs and vertebrae of the E4 group than the S group. With respect to other training-induced effects, the oxygen carrying capacity of the blood, as well as the heart and lung DNA and protein concentrations did not change after four months of exercise training. Within four months, moderate exercise can increase the calcium deposition in the bones of mature, female rats.

Alkaline Phosphatase↗
PubMed1985

[Familial polycythemia caused by high oxygen affinity hemoglobin. 2nd world case of hemoglobin J Providence].

The cas observed in Auvergne and reported here raises the aetiological problem of polycythaemias. Young subjects with polycythaemia should be investigated for congenital anomaly of oxygen transport by measuring P50 and 2,3-DPG, which provides information on the oxygen-carrying capacity of haemoglobin. When confronted with familial polycythaemia due to high oxygen affinity haemoglobin, clinicians must know that a cause-effect relationship is not always demonstrable since other factors, such as tobacco-smoking in this particular case, may intervene.

Adult↗
PubMed1979

A fluted intramedullary rod for subtrochanteric fractures.

A new intramedullary rod has been developed for the treatment of subtrochanteric fractures. The stepped fluted rod is designed as a single unit and has exceptional bending strength and rigidity as well as excellent torsional load-carrying capacity. It has been used successfully in eighteen patients with a variety of subtrochanteric fractures. Union was achieved in all instances and no failure of the implant occurred. The simplified technique of insertion, the strength of the device, and the results of this study indicate that the fluted subtrochanteric rod has several advantages over other available devices.

Adult↗
PubMed1979

Acute fatal DDS poisoning. (Report of 4 cases).

Acute dapsone poisoning is rare and such cases are either accidental or suicidal. Though accidental DDS poisoning are reported in children, the same is fairly uncommon in adults. Only 2 such cases are reported in India literature. We here report 4 cases of fatal sucidial DDS poisoning in adults resulting death in 3 cases. The reported acute symptoms include nausea, vomiting, hyperexcitability followed by depression, Carpopedal spasm or convulsions. The most marked signs are dyspnoea and cyanosis. The symptoms are due to methaemoglobinaemia, and or sulphaemoglobinaemia. Normally dapsone induces red cell haemolysis and even with small therapeutic doses of 25-100 mg per day, and in toxic doses reduces the oxygen carrying capacity of blood and damages the red cells making them more vulnerable for haemolysis. The peculiarity of the presentation in this series are manifestation of severe haemorrhagic episode in one case and progressive jaundice in another besides cyanosis. None of the cases had carpopedal spasm or convulsion. Out of four cases three died inspite of intensive care, intravenous vitamin C, exchange transfusion (2 cases) and other supportive measures. Intravenous methylene blue could not be used in these cases due to non-availability.

Acute Disease↗
PubMed1983

Maternal cigarette smoking and fetal oxygen transport: a study of P50, 2,3-diphosphoglycerate, total hemoglobin, hematocrit, and type F hemoglobin in fetal blood.

The current study was undertaken to determine whether the O2 carrying capacity of newborns born to mothers who smoke can accommodate to carbon monoxide poisoning to compensate for the potential tissue hypoxia induced by CO. From a cohort of 1,222 women and newborn infants the total hemogloblin concentration, hematocrit, and carboxyhemoglobin (HbCO) were measured and analyzed with regard to the maternal HbCO level and the number of cigarettes smoked per day. Also, for 100 pairs of mothers, of whom 50 were smokers and 50 nonsmokers, and their newborns, measurements were made of the intraerythrocyte concentration of 2,3-diphosphoglycerate (2,3-DPG), the hemoglobin concentration, and the affinity of hemoglobin for oxygen by determination of O2 tension for 50% of Hb-O2 saturation (P50). The results showed no significant relationship between smoking habits of mothers and their levels of hemoglobin, P50, and 2,3-DPG; only the hematocrit was slightly increased in smoking mothers. However, in fetal blood a significant correlation was found between the number of cigarettes smoked per day and levels of hemoglobin, hematocrit, and P50. The P50 decreased in relationship to the increase in maternal HbCO. The P50 change was brought about by an increase in hemoglobin F found in the fetuses of mothers who smoked. Although all these changes were statistically significant, these mechanisms of acclimatization to CO poisoning appeared trivial in magnitude. It is concluded that the human fetus does not have a biologic capacity to accommodate to maternal cigarette smoking, and therefore the fetus is particularly susceptible to the adverse effects of cigarette smoking.

2,3-Diphosphoglycerate↗
PubMedDate not supplied

Treatment of postischemic reperfusion cardiac injury with a perfluorochemical solution.

We assessed the effects of a perfluorochemical solution on reperfusion injury in a globally ischemic heart model. An isolated rabbit heart, retrogradely perfused at a constant flow rate, served as our experimental model. After initial perfusion with whole blood, hearts were exposed to 30 min of normothermic global ischemia. Reperfusion was then begun with either whole blood or a 20% perfluorochemical solution (FC-43). After 120 min of reperfusion, a markedly greater recovery of contractile function was observed in the perfluorochemical-reperfused hearts (85 +/- 5% of baseline developed pressure) compared with blood-reperfused hearts (57 +/- 3% of baseline developed pressure). This recovery of function was accomplished with only 1 h of perfluorochemical reperfusion and was not lost on returning to blood perfusion. The improved recovery of function could not be attributed to the chemical composition, oxygen-carrying capacity, pH, or temperature of the perfluorochemical perfusate. Neither could the beneficial effects of perfluorochemical be related to differences in left ventricular resting pressure. We speculate that, because of marked differences in coronary resistance during reperfusion with perfluorochemical solution and blood, improved recovery of cardiac function is related to the superior rheological properties of perfluorochemicals.

Animals↗
PubMed1983

Blood substitutes: where are we?

Plasma volume expanders exist and are available. Balance salt solutions are preferred for initial resuscitation. Albumin should be avoided. Synthetic coagulation factors are not available. They exist because proper component therapy creates them to be stored for selective use. A substitute for the prime function of blood--oxygen delivery by the red cell--does not yet exist. Its clear that one is needed; the form is not yet identified. Fluorocarbon emulsions have a certain chemical cleanliness that makes them appealing, yet there are many unanswered questions, especially as to oxygen-carrying capacity and toxicity. Fluorocarbons have been pushed to clinical testing before their time. Chemically modified stroma-free hemoglobin continues to evolve and develop as a useful blood substitute. Most of the early problems seem to have been resolved and a third generation of molecules, the second set of modifications, is promising.

Animals↗
PubMed1983

[Combined use of mannitol and perfluorochemicals in experimental cerebral ischemia].

Using the "canine model of complete ischemic brain regulated with a perfusion method" in which it is possible to control the degree of blood flow to a cerebral hemisphere via a perfusion pump, the effects of mannitol (which acts as a free radical scavenger) and perfluorochemical emulsion (PFC, which has 0.1 micrograms of average particle size and a high oxygen-carrying capacity) on cerebral ischemia were investigated. After pretreatment with the drugs, blood flow was reduced via the pump to 1/10 of the normal flow volume and 1 hour later, return to a normal flow was allowed. Subsequent changes in electrical activity were observed and the effects of the drugs evaluated. In the control group, no recovery of electrical activity was seen, but in the animals treated with either mannitol or PFC, incomplete, yet distinct recovery was apparent. In the animals administered with mannitol together with PFC, however, marked recovery was evident. These experimental results indicated that a combined administration of PFC and mannitol is effective in protecting the brain from cerebral ischemia.

Animals↗
PubMed1984

The use of hemoglobin solutions in kidney perfusions.

Solutions of hemoglobin have often been considered for both hypothermic and normothermic perfusion of isolated kidneys. This paper considers basic issues, preparative techniques, and the viscosity of hemoglobin solutions, as well as the demands made by the kidney on a perfusate. The natural system of oxygen transport in higher animals is complex, and its perturbation to produce convenient hemoglobin-based renal perfusates produces numerous problems. The desirable effect of 2,3-diphosphoglycerate is not easily maintained in a perfusate, but its inclusion can be avoided by appropriate choice of species donating hemoglobin. Hemoglobin tetramer in free solution may dissociate and be lost by glomerular filtration. Ferric hemoglobin, the dominant form at redox equilibrium, is useless for oxygen transport; the ferrous form is maintained in the erythrocyte by reducing metabolites and, under normothermic conditions, the ferrous to ferric conversion is slow but significant. Methods for lysis of erythrocytes and removal of their stroma are discussed; reduction of ferric hemoglobin by chemical agents and electrolysis are considered in detail; and means for adjusting concentration and solute background are presented. The need for carbonic anhydrase in hemoglobin solutions used as perfusates is shown and methods for its provision are discussed. A review of viscometric data for hemoglobin solutions is provided to which original data are added. Hemoglobin solutions show a temperature-independent intrinsic viscosity, according to Einstein's theory for a molecule of 23 A radius. The O2 and CO2 transport requirements of renal perfusates are analyzed comprehensively. The normothermic kidney has an unusual respiration pattern, requiring an amount of oxygen that is not fixed but, rather, proportional to the total blood flow rate. In canines the average arterio-venous O2 content difference found by many investigators is 2.14 vol%; the corresponding CO2 value is 2.47 vol%; and the respiratory quotient is greater than unity. Wide limits of PO2, but not P CO2 in perfusate, appear allowable. A final section evaluates hemoglobin solutions as both normothermic and hypothermic renal perfusates from the viewpoints of blood gas chemistry, urinary loss, oncotic pressure, fatty acid carrying capacity, viscosity, and the need for functions usually attributed to platelets. It is concluded, overall, that perfusates containing free hemoglobin have only a limited role to play in renal perfusion.

Animals↗
PubMed1983

Encapsulation of exogenous agents in erythrocytes and the circulating survival of carrier erythrocytes.

Erythrocytes can be made to entrap enzymes, lipids, drugs, pesticides, and large macromolecules by a variety of encapsulation procedures. Methods of encapsulation include hypotonic dilution and dialysis, lipid fusion, electrical hemolysis, and chemical perturbation. The survival of carrier erythrocytes is dependent on the method of encapsulation as is the encapsulation efficiency. Research has led to utilization of carrier cells for drug and enzyme-replacement therapies, for incorporation of DNA and antibodies into living cells, and for enhancement of the oxygen-carrying capacity of hemoglobin. Many of the possible uses of erythrocytes as carriers are explored.

Animals↗
PubMed1981

[Development of new methods in suppressing brain infarction--combined administration of mannitol and perfluorochemicals (author's transl)].

Various therapeutic methods have been attempted for cerebral infarction, but the development of more effective methods is still awaited. We have investigations of the effect of mannitol in preventing the development of cerebral infarction and have reported it effects in clinical cases of operated cerebral aneurysms. In recent years, our attention has been drawn to the so-called red cell substitute, perfluorochemicals (FC), which has a high oxygen-carrying capacity and a small particle less than 0.1 mu. In the present studies, using infarction models in dogs which have previously developed and reported, observations are made on recovery of brain electrical activity in severe ischemia, suppressing brain swelling following recirculation of cerebral blood flow and protection upon the hemorrhagic brain infarction, due to administration of mannitol or FC. These experimental results indicate that the combined administration of mannitol and FC is effective in protecting the brain from cerebral ischemia.

Animals↗
PubMed1984

In vivo evaluation of pyridoxalated-polymerized hemoglobin solution.

Previous evaluations of stroma free hemoglobin solutions (SFHS) revealed two problems, a low P50 (13 to 15 torr) which theoretically limits oxygen off-loading to tissues, and a short intravascular half time of only 3.5 hours. To correct these problems the hemoglobin molecule was pyridoxalated and polymerized to raise the P50 (20 to 22 torr) and to increase the plasma half-disappearance time to 25 hours. In the current investigation, rats exchange transfused to 75 per cent of their initial blood volume with SFHS exhibited centrilobular liver necrosis 12 and 24 hours after the transfusion as a result of the hypovolemic state induced by the hemoglobin diuresis. In contrast, animals administered pyridoxalated polymerized hemoglobin solution (Pr-Pl-Hb) displayed a normal hepatic morphologic finding. Renal morphologic findings in the two groups were similar except for the smaller quantities of hemoglobin observed in the proximal and distal tubules of Pr-Pl-Hb animals. This finding may be a result of the slower degradation of Pr-Pl-Hb in the intravascular compartment. Renal function in Pr-Pl-Hb remained normal after exchange transfusion, while the BUN in SFHS treated animals increased significantly due to the state of dehydration. Thus, Pr-P1-Hb represents an improvement over the previously tested SFHS in both P50 and intravascular half-time and, because of lowered osmotic and oncotic activities, it may be used in higher concentration to improve oxygen carrying capacity.

Animals↗
PubMed1984

Serum lipids and lipoprotein composition in spontaneously diabetic BB Wistar rats.

Serum lipid and lipoprotein composition in spontaneously diabetic BB Wistar rats, nondiabetic littermates, and control Wistar rats was studied to elucidate diabetes-related abnormalities of lipoprotein composition. Serum total triglycerides and pre-beta-lipoprotein concentrations of insulin-treated spontaneously diabetic BB and nondiabetic littermate rats were significantly higher than those of control Wistar rats. Serum cholesterol and HDL cholesterol concentrations of spontaneously diabetic BB and nondiabetic littermate rats did not differ from controls. Concentrations of very low density lipoproteins (VLDL), low density lipoproteins (LDL), and high density lipoproteins (HDL) of spontaneously diabetic BB and nondiabetic littermate rats were higher than those of normal rats. With sodium dodecylsulfate-polyacrylamide gel electrophoresis it was observed that the spontaneously diabetic BB and nondiabetic littermate rat VLDL contained higher percentages of apoE relative to total apoC when compared with control Wistar rats. With isoelectric focusing, apoC-II relative percentages in VLDL and HDL of both spontaneously diabetic BB and nondiabetic littermate rats were higher than apoC-II proportions in VLDL and HDL of controls. Apolipoprotein A-I of the control rat HDL showed four isoforms that focused at pI 5.8 (17.3%), 5.75 (30.6%), 5.65 (31.8%), and 5.55 (20.5%); however, the spontaneously diabetic BB and nondiabetic littermate rat HDL apoA-I was mainly represented by two isoforms that focused at pI 5.8 and 5.75. VLDL of both diabetic and nondiabetic BB rats contained higher levels of acidic apoE isoforms compared to their counterparts in control Wistar rats. Although HDL cholesterol concentrations of spontaneously diabetic BB rats remained normal, protein concentrations were higher resulting in a low cholesterol/protein ratio in HDL suggesting that the cholesterol-carrying capacity of spontaneously diabetic BB rat HDL could be less than normal and may be due to an abnormal apoA-I composition. Quantitative alterations of lipid and lipoprotein composition appear in the BB Wistar rat when compared to the Wistar rat, but some of the changes are more pronounced in the spontaneously diabetic BB Wistar rat.

Animals↗
PubMed1984

[Contrast material with oxygenated Fluosol-DA, 20 for the protection against complications of catheter cerebral angiography].

Although computed tomography may change the criteria of cerebral angiography in neurosurgery, the neurosurgeon still requires angiographic confirmation of vascular anatomy at the operative sites, and catheterization for intra-luminal constructive surgery is also seeing progress. Cerebral angiography is a rather safe procedure; however, persistent serious neurological deficits and fatal complications are occasionally reported. The mechanisms of these complications are considered to be due to mechanically dislodged fragments of clots and/or atheroma, or direct endothelial damage by the catheter, contrast agents toxicity to brain tissue, anoxic neurocytologic injury due to the disturbance of the blood flow. Fluosol-DA (a type of perfluorochemical) has a potent oxygen-carrying capacity and has been safely used in humans as an artificial blood substitute. Meglumine diatrizoate (65% Angiografin) has not lost the x-ray opacification faculty in cerebral angiography by mixing with oxygenated Fluosol-DA, 20 up to 30 vol % of the latter in clinical use. In animal experiments, from 0.25 to 4 ml/kg of Angiografin-65 or Angiografin-65 with oxygenated Fluosol-DA, 20 were injected into the internal carotid artery of mongrel dogs. When 2.0 ml/kg of Angiografin-65 was injected into the carotid artery, remarkable arrhythmia was observed for 7.5 seconds. Blood pressure dropped 28.3 mmHg for 20.2 seconds; thereafter, it increased 25 mmHg in rebound for 15 seconds. Intracranial pressure increased 5 mmHg for 35 seconds, respiratory disturbance continued for 22.6 seconds. When a 20 vol % mixture of Fluosol-DA, 20 with Angiografin-65 was applied, these adverse reactions were markedly reduced.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1983

A critique of applications of the Euler equation to the human spine.

The Euler buckling theory has been presented as evidence that spinal curves increase the spine's axial load carrying capacity. The Euler theory is however, derived for an initially straight beam or column and as such cannot be applied to initially curved structures, such as the human spine.

Biomechanical Phenomena↗
PubMed1984

Total bloodless open heart surgery in the pediatric age group.

Forty-eight pediatric open heart surgical procedures were performed with bloodless techniques regardless of surgical complexity or presence of cyanosis at the Children's Hospital of Buffalo. Priming solution for cardiopulmonary bypass was reduced to avoid excessive hemodilution, and careful surgical techniques were used to minimize blood loss. Hypothermia compensated for decreased oxygen-carrying capacity and made it possible to reduce bypass flow safely. Tissue perfusion and oxygenation on bypass appeared comparable to or better than those in a control group that underwent open heart surgery with milder degrees of hemodilution. All patients tolerated bypass uneventfully without transfusion. Platelet counts were higher and blood loss less marked than those in the control group. Prevention of excessive dilution by priming solution seemed most important for preservation of platelets and subsequent hemostasis. Four of the smaller infants with complex cyanotic defects needed postoperative transfusion, while 44 patients did not receive transfusion at all during their hospital stay. Total blood product requirement was reduced from 11.5 to 0.35 units per patient. Intracardiac surgery without transfusion is possible in most pediatric patients without evidence of increased risk.

Blood Transfusion↗