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PubMedDate not supplied

Relation between lowered colloid osmotic pressure, respiratory failure, and death.

Plasma colloid osmotic pressure was measured each day in 84 intensive care unit patients. Probit analysis demonstrated a direct relationship between colloid osmotic pressure (COP) and survival. The COP associated with a 50% survival rate was 15.0 torr. COP was higher in survivors than in nonsurvivors without respiratory failure and in patients who recovered from respiratory failure. We conclude that lowered COP is associated with an elevated mortality rate. However, the relationship to death is not explained by the relationship to respiratory failure.

Colloids↗
PubMed1980

Comparison of measured and calculated colloid osmotic pressure of serum and pulmonary edema fluid in patients with pulmonary edema.

Serum and pulmonary edema fluid samples of 26 patients with pulmonary edema were examined. The correlation coefficient comparing measured colloid osmotic pressure (COPm) to calculated colloid osmotic pressure (COPc) (Landis and Pappenheimer equation) was 0.84. Significant differences between COPm and COPc were noted when total protein (TP) concentrations were less than or greater than 5 g/dl (p < 0.001 and p < 0.01, respectively). Twenty-one of 69 samples (30%) had a greater than 4 mm Hg difference between measured and calculated values. COP should be measured rather than calculated for accurate determinations.

Adult↗
PubMed1981

Colloid osmotic pressure of normal newborns and premature infants.

Colloid osmotic pressure (COP) is an important regulator of fluid movement and can now be measured simply and reliably. The authors used the 4100 Wescor Colloid Osmometer to define COP values and its relation to total protein concentration (TP) in different groups of newborns. The mean COP was 19.4 +/- 2.2 (SD) torr in 99 term infants delivered vaginally and 16.0 +/- 2.1 in 40 term infants delivered by cesarean section (p less than 0.005). The COP was lower in those born operatively without preceding labor (14.9 +/- 1.8). COP correlated well with TP (r = 0.92) in term infants. In 60 sick preterm infants with 362 determinations, COP (12.5 +/- 2.5) was different from term infants (p less than 0.001) and the correlation with TP was poor (r = 0.64). Different therapeutic modalities were found to affect COP widely. Crystalloid infusion decreased COP by 22% and surgery by 32%. The authors conclude that COP varies not only with gestational age but also with mode of delivery and experience of labor. In critically ill preterm neonates, because estimations form TP are inadequate, the only way to obtain a quantitative measure of COP is by direct measurement. Repeated measurements of COP will permit precise selection of the fluids and will warn of changes that may lead to pulmonary edema.

Asphyxia Neonatorum↗
PubMed1982

Colloid osmotic pressure and fluid resuscitation with hetastarch, albumin, and saline solutions.

The effects of fluid resuscitation with 6% hetastarch, 5% albumin, or 0.9% saline solutions on plasma colloid osmotic pressure (COP) were examined in 26 patients with hypovolemic circulatory shock. One liter of hetastarch produced a 36% increase in COP compared to an 11% increase after 1 L of albumin (p less than 0.001). One liter of saline resulted in a 12% decrease in COP (p less than 0.05). The mean COP increased from 16.3 +/- 1.6 (SE) mm Hg to a maximum of 23.7 +/- 1.4 mm Hg during the first 24 h of hetastarch resuscitation (p less than 0.01), and from 17.0 +/- 1.1 to 22.3 +/- 1.5 mm Hg with albumin (p less than 0.001). Saline resuscitation decreased the COP from 17.1 +/- 1.1 mm Hg to a minimum of 12.7 +/- 1.1 mm Hg (p less than 0.02). These changes persisted from 2-5 days after resuscitation. Saline resuscitation required significantly larger amounts of fluid. The authors conclude that fluid resuscitation of circulatory shock with colloid solutions increases COP and requires less volume of resuscitative fluid.

Aged↗
PubMed1983

Hemodynamic and colloid osmotic pressure alterations in the surgical patient.

Colloid osmotic pressure (COP) was measured simultaneously with cardiorespiratory measurements in 103 surgical patients suspected of having circulatory problems. In a small subset of 28 patients, measurements were taken before, during, and after surgical operations. Similarly, data sets were taken before, during, and after infusions of colloids and crystalloids to assess the interactions of these variables during the stress of surgery and the administration of fluid therapy. COP was found to decrease during and shortly after surgical operations despite reasonably well-maintained pressure, volume, and flow variables. Concentrated (25%) albumin and plasma protein fraction (PPF) increased COP, cardiac index (CI), CVP, pulmonary capillary wedge pressure (WP), and blood volume, whereas crystalloids transiently increased CI, CVP, and WP but did not significantly change COP and blood volume. Low COP values were weakly related to survival, and COP-WP differences less than or equal to 3 mm Hg were roughly related to ARDS and pulmonary edema.

Blood Physiological Phenomena↗
PubMed1987

Effects of three colloid solutions on plasma volume and hemodynamics after coronary bypass surgery.

The effects of 4% plasma protein solution (group P), 6% dextran-70 (group D), and 5.5% oxypolygelatin (group G) on plasma volume and hemodynamics were compared with each other and with controls (group C) who received only maintenance infusion 20 h after coronary bypass surgery. After infusing 10 ml/kg of colloid at 1 g/min, the immediate increases in plasma volume were 6.1 ml/kg in group P, 8 ml/kg in group D, and 7.9 ml/kg in group G. After one hour, the corresponding increases were 4.2 ml/kg (group P), 8.2 ml/kg (group D), and 6.2 ml/kg (group G). The increases in pulmonary capillary wedge pressure and stroke index were greatest and most persistent in group D, second largest but shortest in duration in group G, and lowest in group P. In conclusion, the volume effects of these three colloid solutions in coronary bypass patients are comparable to those obtained in other elective surgical patients.

Blood Proteins↗
PubMed1987

Effects of colloid or crystalloid solutions on edemagenesis in normal and thrombomicroembolized lungs.

We studied the effects of crystalloid (75 ml/kg of Ringer's lactate) or colloid (6% dextran-70, 6% hydroxyethyl starch, or 25 ml/kg of 5% human serum albumin) fluid infusions or no treatment (control) on the calculated lung capillary (Pc)-plasma oncotic pressure (pi c) gradient and pulmonary edema. Two sets of mongrel dogs were studied: uninjured (n = 25; 14 to 22 kg) and pulmonary fibrin-microembolized (n = 25; 15 to 23 kg). In both sets of experiments, left atrial pressure was controlled (15 mm Hg) throughout the 4-h plus experimental period. In the uninjured set, the Pc-pi c gradient averaged +1.0 and -0.2 mm Hg in the hydroxyethyl starch and dextran groups, +0.7 and +2.3 mm Hg in the human serum albumin and control groups, and +6.2 mm Hg in the Ringer's lactate group. In the fibrin-microembolized group, this gradient averaged 2.6, 2.4, 3.0, 5.3, and 9.5, respectively. The extravascular lung water to bloodless dry lung wet weight ratios in the no-fluid treatment group of the uninjured and microembolism groups with increased pressure (3.8 +/- 0.3 to 4.1 +/- 0.4 [SEM]; NS) are consistent with interstitial or perivascular edema. There were, however, no significant differences noted between the respective control groups or any fluid treatment group in either set of experiments. These data support the view that infusion of either colloid or crystalloid solutions in normal or pulmonary fibrin-microembolized lungs does not produce sufficient change in the Pc-pi c gradient to elevate edemagenesis when pulmonary capillary pressure is limited to 22 mm Hg in dogs.

Animals↗
PubMed1987

Detection of acute gastrointestinal bleeding by intra-arterial Tc-99m sulfur colloid scintigraphy in a canine model. Preliminary study.

The diagnostic sensitivities of arteriography, intravenous (IV) Tc-99m sulfur colloid scintigraphy, and intra-arterial (IA) Tc-99m sulfur colloid scintigraphy were evaluated in a canine model of gastrointestinal bleeding. Fifteen dogs were studied at bleeding rates ranging from .4 to 1.0 ml/minute. All three studies were obtained in six of the 15 dogs. Intravenous scintigraphy was superior to angiography in two cases, inferior in three, and equal in one. No significant difference could be shown between these two tests at these bleeding rates. Intra-arterial scintigraphy was superior to angiography in four cases and equal in two (P = .06). It was superior to IV scintigraphy in five cases and inferior in one (P = .10). In this small preliminary study, IA scintigraphy appears to be superior to the other two modalities and may prove useful in the detection of acute bleeding at the time of negative arteriography, and in serial studies in patients receiving Pitressin.

Acute Disease↗
PubMedDate not supplied

Chondroitin sulfate iron colloid as an MR contrast agent for the hepatic reticuloendothelial system.

OBJECTIVE: Chondroitin sulfate iron colloid (CSI), a therapeutic agent for asiderotic anemia, is widely used in the clinical field, and its safety has been established in Japan. We studied the potential of this agent for MRI of the hepatic reticuloendothelial system. Chondroitin sulfate iron colloid has a paramagnetic trivalent iron ion and is effective in shortening T2 relaxation time because it is taken up rapidly in the hepatic reticuloendothelial system after intravenous injection. MATERIALS AND METHODS: Hepatic MR images were obtained before and 1 h after the intravenous injection of 26.9 mumol Fe/kg of CSI in rats with experimentally induced tumors and of 18-30 mumol Fe/kg in human subjects. RESULTS: The signal intensities of normal hepatic tissue were decreased in all cases, whereas those of tumors were unchanged after CSI injection in these two series. Consequently, good contrast was observed in each pulse sequence. CONCLUSION: Therefore, CSI seems to be clinically useful as a contrast agent for hepatic MRI.

Animals↗
PubMed1976

Organ culture of craniopharyngioma and its cellular effects induced by colloidal chromic phosphate.

Since a marked clinical improvement has been reported following chromic phosphate treatment in recurrent craniopharyngioma, we have attempted to study the in vitro cellular changes of two craniopharyngiomas maintained in organ culture system and subsequently treated with colloidal chronic phosphate. When incubated for 24 and 48 hours respectively, at a concentration of 10 muCi/ml. of colloidal 32P, only vacuolar degeneration and hyperchromasia of the tumor cells have been observed. When incubated with 50 muCi/ml. for 24 hours, further cellular degeneration and focal necrosis begin to appear. Up to 48 hours after 50 muCi/ml. obvious necrosis and extensive degeneration become apparent. Autoradiography confirms the fact that radioactive material is absorbed by the tumor cells. Brain tumors when maintained in an organ culture system may serve as a useful model for the evaluation of the effects of various chemotherapeutic and radiotherapeutic agents in vitro.

Adult↗
PubMed1989

Effects of crystalloid and colloid infusions on intracranial pressure and computerized electroencephalographic data in dogs with vasogenic brain edema.

This experiment was designed to study the effects of intravascular volume expansion with crystalloid and colloid agents on intracranial pressure (ICP) and computerized electroencephalographic (EEG) data in dogs with cerebral vasogenic edema. A liquid nitrogen cold lesion was produced in the right parietal lobes of 30 anesthetized mongrel dogs. ICP data from an intraventricular catheter, hemodynamic data, and EEG power data were recorded continuously during the course of the experiment. Six hours after creation of the liquid nitrogen cold lesion, each dog was infused with one of the following treatments: 1) no treatment (control); 2) 5% dextrose in water (D5W) (30 ml/kg/h); 3) 0.9% NaCl (30 ml/kg/h); 4) hetastarch (10 ml/kg/h); and 5) hetastarch (30 ml/kg/h). The animals were treated for 2 hours, killed, and the brains examined and measured for water content. During the D5W infusion, ICP increased significantly (141%) but the EEG power data did not change. During the normal saline infusion, ICP increased significantly (91%) and the EEG power data showed marked deterioration. Both hetastarch infusions produced no change in ICP and demonstrated an improvement in the EEG power data (P less than 0.001). These data suggest that crystalloid infusions may have profound deleterious effects in the presence of brain edema, but colloids do not, and should be considered in the fluid management of patients with cerebral edema.

Animals↗
PubMed1986

99Tcm-(tin) colloid scans in the evaluation of renal transplant rejection.

Technetium-99m-(tin) colloid uptake in renal transplants was quantified to evaluate rejection. A dynamic acquisition following i.v. injection of 110 MBq of this radiopharmaceutical enabled quantification of 15 to 20 min transplant uptake (PU), in terms of percentage of an injected dose after allowing for attenuation in the patient. An uptake ratio (UR) i.e. the ratio of 15 to 20 min uptake over the 0 to 5 min uptake was also derived. Normal values were obtained in 20 stable functioning transplants (normal PU less than or equal to 1%, normal UR less than or equal to 0.7). In 66 patients, PU and UR were compared with clinical, biochemical, histological and radiological, evidence of rejection. A sensitivity of 70% and specificity of 85% was obtained for this 99Tcm-(tin) colloid study in the diagnosis of renal transplant rejection.

Colloids↗
PubMed1988

Binding of 99Tcm sulphur colloid to blood components: implications in renal transplant rejection.

The percentage binding of 99Tcm sulphur colloid to blood components (formed elements and plasma proteins) was studied within 1 min of the intravenous injection of the radiopharmaceutical in humans as well as rats. In humans, 68% of the total blood counts were bound to the formed elements (erythrocytes, leucocytes and platelets). The binding pattern (as percentage of plasma counts) among the plasma protein fractions in humans was as follows: albumin, 9.85 +/- 2.06; fibrinogen, 56.70 +/- 7.96; and total proteins, 66.55 +/- 7.32. Activity bound to fibrinogen represented 82.3 +/- 9.1% of the total protein-bound activity in humans. In rats as well fibrinogen was the predominant binding protein (73.8 +/- 5.6). The significant binding of the 99Tcm sulphur colloid to plasma fibrinogen and formed elements of blood may be one of the reasons for the uptake of this radiocolloid in renal transplants before rejection.

Animals↗
PubMed1992

Correlation of splenic function with the splenic uptake rate of Tc-colloids.

The splenic uptake rate of Tc-sulphur colloid or Tc-tin colloid was measured and found to correlate well with splenic function. The normal tracer uptake rate was 0.0002/s-0.0006/s (measured uptake rate divided by measured injected activity). Lower values indicated hyposplenism (sensitivity = 0.97, specificity = 0.95), and values over 0.0006/s indicated hypersplenism (sensitivity = 0.96, specificity = 0.97). Higher values of splenic uptake were associated with proportional reductions in the white blood cell and platelet counts, and to a lesser extent the haemoglobin concentration in peripheral blood. Patients with rheumatoid arthritis had increased tracer uptake, but still below the criteria for hypersplenism, whereas patients with Felty's syndrome had tracer uptake rates in the 'hypersplenic' range.

Humans↗
PubMed1992

The importance of a colloid in canine pancreas preservation.

The role of hydroxyethyl starch (HES), the colloid component of the UW solution, was tested in canine pancreas preservation. Segmental pancreatic autografts were preserved for 48 hr cold storage with UW solution with HES (group 1) or UW solution without HES (group 2). After preservation, the pancreas was transplanted, and survival, serum glucose, serum amylase, intravenous glucose tolerance tests, tissue water content, and histology were compared between groups. In group 1 (with HES), 9/10 dogs were long-term survivors with one dog dying due to causes unrelated to preservation failure. In group 2 (without HES), 3/6 dogs died due to graft loss within one week posttransplant (P = 0.01). No graft failure occurred in group 1 (0/9) versus graft loss in 4/6 dogs in group 2 (P = 0.04). All animals in group 1 (with HES) showed normal serum glucose and amylase concentrations postoperatively, normal tissue water values after preservation, k values comparable to those observed after segmental autotransplantation without preservation, and relatively good histology. In group 2 (without HES), in 4/6 dogs graft failure occurred that led to the death (3 dogs) of the animals or to a diabetic state (1 dog). After 48-hr cold storage without HES, a significant increase in tissue water content, glucose and amylase levels was seen. After transplantation, hyperglycemia, hyperamylasemia, and clinical diabetes were observed in 4/6 dogs. Autopsy and histological evaluation showed evidence of thrombosis and ischemic insult. Two of 6 dogs in group 2 remained normoglycemic during follow-up with borderline k values. The results suggested that for consistently successful 48-hr preservation of the pancreas, HES is an important component of the UW solution. Although a colloid may not be essential for short-term preservation of kidney and liver, it appears to be an important factor in successful pancreas preservation.

Adenosine↗
PubMed1992

Technetium-99m sulfur colloid accumulation as a predictor of acute renal transplant rejection.

Renal transplantation is the preferred treatment for end-stage renal disease in children. Most transplant failures are due to allograft rejection. To date, only histopathological findings on renal biopsy can establish this diagnosis. Prior to the availability of cyclosporine, technetium-99m sulfur colloid nuclear scans (TSC) were used in a limited number of institutions to detect rejection episodes. The purpose of this study was to determine whether TSC could predict acute rejection in the cyclosporine era. A prospective study involving 41 pediatric renal transplant patients (M = 25, F = 16) was conducted from 6/1/89 to 10/31/91. Patients who received a TSC and biopsy (41 patients, 62 studies) within one week of clinical and laboratory evidence of acute rejection were included in the study. A qualitative method of determining sulfur colloid uptake was used by comparing allograft uptake with that of the fifth lumbar vertebrae (L5) marrow uptake: 3(+)--allograft with greater than L5 marrow uptake, 2(+)--same as, 1(+)--less than, and 0--no allograft uptake. Transplant accumulation of > or = 2+ was considered consistent with acute rejection (P < 0.001). Acute rejection was noted in 53 of 62 renal biopsies. Of those with biopsy-proved acute rejection, SC was positive (> or = 2+) in 46 of 53. SC of > or = 2+ has proved to be a good predictor of acute rejection. This technique has a sensitivity of 98%, specificity of 53%, positive predictive value of 87%, and negative predictive value of 89%.

Adolescent↗
PubMed1996

Protection of isolated lung from reperfusion injuries by rinsing with high colloidal osmotic solution with deferoaxmine.

We examined the efficacy of rinsing isolated lungs subjected to prolonged hypothermic storage with a high colloidal osmotic pressure solution prior to ex vivo blood reperfusion in order to preserve physiologic functions, suppress peroxidation of mitochondrial membranes, and inhibit infiltration of neutrophils. Isolated rabbit lungs were flushed with a Rinse-1 solution (289 mOsm/kg H2O) to remove remaining blood and immersed in physiologic saline at 8 degrees C for 24 hr. The control group received blood reperfusion immediately after storage; the Rinse-1 group was rinsed with Rinse-1 solution before blood reperfusion and the Rinse-2 group with Rinse-2 solution (312 mOsm/kg H20) including deferoxamine. Reperfused blood was passed through an artificial membranous lung to reduce oxygen tension (PO2) to the venous level, and time-dependent changes in airway pressure (AWP), pulmonary artery pressure (PAP), and PO2, as a measure of gas-exchange capability were examined. We estimated the lipid peroxide level in mitochondrial membranes as thiobarbituric acid-reactive substances (TBARS), i.e., malonedialdehyde, and neutrophil infiltration into lung tissue by measuring myeloperoxidase activity after 60 min of blood reperfusion. The PO2 was significantly higher in both rinsed groups compared with the control, while neither AWP nor PAP was significantly different in the three treatment groups. Both mitochondrial TBARS and myeloperoxidase activity were significantly higher in the control group compared with either rinsed group. These results indicate that rinsing stored lungs with a solution of high colloidal osmotic pressure prior to blood reperfusion was effective in preserving physiologic function and inhibiting neutrophil infiltration. Addition of deferoxamine was markedly effective in reducing TBARS formation and lessening reperfusion injury of stored lungs.

Animals↗
PubMed1998

Transport and retention of colloidal tracers in regional lymphoscintigraphy in melanoma: influence on lymphatic mapping and sentinel node biopsy.

Sentinel node (SN) biopsy is a staging technique used to select patients for regional lymphadenectomy in melanoma. We compared the two most widely used radioactive tracers, 99mTc-colloidal albumin (99mTc-CA) and 99mTc-sulphur colloid (99mTc-SC), with respect to scintigraphy, success rate in gamma probe guided biopsy and absolute uptake in the SN. Scintigraphy was performed in six volunteers after simultaneous injection of the respective tracers in each leg. Comparison of uptake of both tracers showed a higher uptake on the 99mTc-CA side. The scintigraphic count ratio of SNs labelled with 99mTc-SC compared with 99mTc-CA was 1 to 9 28. Next, 20 patients with biopsy-proven melanoma were randomized for injection of 99mTc-CA or 99mTc-SC followed by SN biopsy. Within 20 min after the injection, focal uptake was seen in all cases of the 99mTc-CA group but in only seven of the 10 patients in the 99mTc-SC group (P < 0.05). Focal accumulations were seen in all patients of both groups after 2 h. Spill to non-SNs was seen in five of the 99mTc-CA patients and three of the 99mTc-SC patients. In all patients the SNs could be retrieved under the guidance of a gamma probe and blue dye. The uptake in the SN was significantly higher (P < 0.001) after the injection of 99mTc-CA (0.92+/-0.40%) compared with 99mTc-SC (0.34+/-0.34%). When dynamic scintigraphy is performed, 99mTc-CA is preferable. SN uptake of 99mTc-SC is less than that of 99mTc-CA but this does not adversely affect the surgical procedure.

Adult↗