Ringer's Lactate Group Research Articles

Hemodynamics of respiratory failure in rabbit model: effect of surfactant supplementation.

In some infants, administration of surfactant has been associated with an acute decrease in blood pressure. We hypothesized that independent of patent ductus arteriosus, low blood volume sensitizes to a negative hemodynamic response to surfactant supplementation. Respiratory failure was induced by bronchoalveolar lavage (BAL) in 30 young rabbits that were paralyzed and ventilated using tidal volumes of 10 ml/kg. After BAL, 15 ml/kg blood was withdrawn while the same volume of one of the following was infused: Ringer's lactate (n = 12); 5% albumin (n = 5); or leukocyte-free red blood cells (RBC, n = 6). The controls were not phlebotomized (n = 7). After blood withdrawal and transfusion, natural surfactant was given (100 mg/kg). The blood volume and pulmonary capillary leak were calculated. Cardiac output (CO) and vascular resistances were measured (Ringer's lactate; n = 5; controls, n = 4). Blood withdrawal and replacement had no immediate effect on either lung function or hemodynamics. Surfactant supplementation improved the gas exchange in all but the albumin-treated animals that had increased protein concentration in epithelial lining fluid. In the Ringer's lactate group, there was a 35% decrease (p < 0.05) in blood pressure, a 28% decrease (p < 0.05) in CO, and a 54% increase (p < 0.05) in pulmonary vascular resistance, shortly after surfactant administration. In the other groups, there was either a transient (controls) or no (RBC and albumin groups) decrease in blood pressure. The total blood volume and the intrapulmonary blood volume were lower in the Ringer's lactate group than in the RBC group. According to the present results, blood pressure and CO may decrease acutely when exogenous surfactant is administered coincidental with blood loss.

Ibuprofen Improves Survival but Does Not Ameliorate Increased Gut Mucosal Permeability in Endotoxic Pigs

Intravenous lipopolysaccharide (LPS) decreases superior mesenteric arterial blood flow and increases ileal mucosal permeability in pigs. We tested the hypothesis that these phenomena can be ameliorated by pretreatment and posttreatment with ibuprofen. Pentobarbital-anesthetized immature swine were mechanically ventilated (fraction of inspired oxygen, 0.5) and infused with Ringer's lactate (RL) solution (0.8 mL/kg per minute). Animals in group RL (n = 10) received no other interventions. Animals in group RL + LPS (n = 15) were infused with LPS (50 micrograms/kg) from a time range equal to 0 through 60 minutes. Animals in group RL + LPS + ibuprofen (n = 10) were similarly infused with LPS, but in addition, they received ibuprofen (10 mg/kg at -30 minutes and 10 mg/kg per hour from -30 through 210 minutes). Intestinal permeability was assessed by measuring plasma-to-lumen clearances of two hydrophilic probes (chromium 51-labeled edetic acid monohydrate [EDTA] and urea) and by expressing the results as a clearance ratio (CEDTA/CUREA). Survival was 100%, 67%, and 100% in groups RL, RL + LPS, and RL + LPS + ibuprofen, respectively. Among survivors only, CEDTA/CUREA increased significantly over time in both endotoxic groups, but not in nonendotoxic controls. Treatment with ibuprofen transiently blocked LPS-induced mesenteric hypoperfusion. These data indicate that mediators other than cyclooxygenase-derived metabolites of arachidonic acid are responsible for the adverse effect of LPS on mesenteric permeability to hydrophilic solutes in this porcine model.

The effects of α-α cross-linked hemoglobin on the feeding and locomotor activity of rats

The feeding and locomotor activities of rats were used as an assay for the potentially toxic effects of an oxygen-carrying blood substitute. Rats lived in individual cages where they could feed ad lib by pressing a lever once for each small food pellet, drink water, or run in a wheel; a 12-h light/dark cycle was continuously in effect. After being anesthetized and hemorrhaged one-third of their total blood volume, individual rats were resuscitated with one of the following fluids: their own shed blood (OB), bis(3,5-dibromosalicylfumarate) α-α cross-linked hemoglobin (HbXL), human serum albumin (HSA), or Ringer's lactate (RL). Rats in a fifth group were not resuscitated (NR). During the dark period on the day of hemorrhage, the food intake and running activity of rats in all groups decreased. Food intake and locomotor activity of rats in the HbXL, NR and OB groups were more suppressed than the HSA or RL groups. The food intake of rats in the HbXL and NR groups remained significantly more suppressed during the dark period of the first recovery day; running continued to be suppressed in the HbXL group on the first recovery day, but not the second recovery day. In an effort to determine the extent to which the rats in the HbXL group were impaired, an increasing number of lever presses was required for each food pellet beginning with recovery day number 3 for all treatment groups. As the ratio of presses per pellet was increased, food intake decreased and running increased for all groups; no differences between groups were significant. The initial impairment of feeding and running in the HbXL group supports the utility of the present procedure as a sensitive bioassay for the potentially toxic effects of hemoglobin substitutes on behavior. The subsequent absence of significant differences between groups during the increasing series of fixed ratios suggests that the effects of α-α HbXL on feeding and running were not lasting.

PRIMING OF CARDIOPULMONARY BYPASS WITH HUMAN ALBUMIN OR RINGER LACTATE: EFFECT ON COLLOID OSMOTIC PRESSURE AND EXTRAVASCULAR LUNG WATER

We have undertaken a randomized study on 20 patients undergoing coronary artery bypass surgery in order to determine the influence of cardiopulmonary pump prime solutions on colloid osmotic pressure and extravascular lung water. Crystalloid priming with Ringer lactate was compared with an albumin solution of nearly physiological colloid osmotic composition (4%). Measurements of extravascular lung water were performed by a modified, highly sensitive thermal dye technique, with additional detection of tracer signals in the pulmonary artery. In the Ringer lactate group, a significantly greater decrease in colloid osmotic pressure occurred immediately after onset of cardiopulmonary bypass. The more pronounced decrease in colloid osmotic pressure and in transcapillary gradient (difference between colloid osmotic pressure and pulmonary capillary wedge pressure) in the Ringer lactate group was associated with a significant increase in extravascular lung water (by 60%) in the postoperative period; the human albumin group, however, showed only a slight tendency to increased lung water. There were no differences in haemodynamic or respiratory states after operation.

Treatment of Hemorrhagic Shock with Intraosseous or Intravenous Infusion of Hypertonic Saline Dextran Solution

The efficacy of intravenous or intraosseous infusion of 250 ml of 7.5% NaCl and 6% dextran 60 (H/H) was compared with intravenous Ringer's lactate (RL) for the initial treatment of patients with hemorrhagic shock due to upper gastrointestinal bleeding. 49 patients were randomly assigned to receive either H/H (n = 26) or RL (n = 23). In the first 16 patients with H/H and in all RL patients, solutions were infused by the intravenous route, while the intraosseous route through sternal puncture was chosen for the last 10 H/H subjects. H/H patients were analyzed together since no differences were noticed between the routes of infusion. The H/H group also received 2.3 +/- 0.7 liters of intravenous crystalloid solutions in the first hour and 4.4 +/- 0.1 liters in the 24-hour period, while RL received 3.3 +/- 0.7 and 7.3 +/- 2.4 liters, respectively. Blood pressure (BP) increased during the first 15 min in the H/H group (from 61 +/- 17/30 +/- 12 to 85 +/- 30/48 +/- 14 mm Hg) and thereafter, while remaining unchanged in the RL group (from 75 +/- 18/40 +/- 12 to 75 +/- 17/40 +/- 14 mm Hg; p less than 0.05). The differences between groups were significant throughout 24 h. Urine output and improvement of the Glasgow Coma Score were also higher in H/H patients than in the control group (p less than 0.05). There were 5 deaths in RL group and 1 in the H/H group. Sternal of peripheral vein infusion of 250 ml of 7.5% NaCl/6% dextran 60 is an effective initial treatment of hemorrhagic shock.

Effect of Ringer's Lactate Irrigation on the Formation of Postoperative Abdominal Adhesions

Intraabdominal adhesions continue to pose a potentially serious postoperative clinical problem. Reported here is an experiment designed to study any effect that balanced Ringer's lactate (RL) solution may have on intraabdominal adhesion formation. Surgical trauma was induced in mice by controlled gauze abrasion of one side of the abdominal wall; the opposite side was used as a control. RL irrigation was compared with no irrigation. Adhesions were scored on the basis of incidence (%) and severity (on a 0-10 scale). The abraded right peritoneum exhibited 100% adhesions for both the RL group and the nonirrigated group. However, on the side that was not abraded, the nonirrigated group showed only 30% incidence of adhesions and 1.7 +/- 3.3 severity as compared with 100% adhesions and 7.7 +/- 2.2 severity for the RL group. These results suggest the need for further studies to establish the extent to which irrigation with solutions such as Ringer's lactate or saline may enhance formation of postoperative adhesions.

A Randomized Prospective Study of Topical Antimicrobial Agents on Skin Grafts after Thermal Injury

We prospectively studied 52 consecutive patients who were treated by early tangential excision and grafting following thermal injury. The usefulness of two topical antimicrobial agents--0.5% silver nitrate (Ag) and neomycin (1 gm/liter) plus bacitracin (50,000 units/liter) (NB)--was compared with the effectiveness of Ringer's lactate (RL) for prevention of autogenous skin-graft loss due to infection. Graft loss of 10 percent or more occurred in 17 patients (33 percent)--due to infection in 16. Skin-graft loss was a minor problem in patients with less than 20 percent total body surface area (TBSA) burn (Ag: 0 of 6, NB: 1 of 6, RL: 1 of 5). The use of either antimicrobial (Ag or NB) resulted in less graft loss (1 of 14) than RL (4 of 6; p less than 0.05) in the 20 to 40 percent TBSA burn group. Large burns (greater than 40 percent) had a very high incidence of at least 10 percent graft loss (67 percent) regardless of treatment. Infection in the area of graft loss was caused by antibiotic-resistant organisms or yeast in 50 percent of the Ringer's lactate group and the entire neomycin plus bacitracin group. No graft infections were caused by resistant organisms or yeast in the silver nitrate group. This study demonstrates that topical antimicrobial agents reduce infection-related skin-graft loss in patients with medium-sized (20 to 40 percent TBSA) burns and that neomycin plus bacitracin is associated with rapid emergence of drug-resistant organisms whereas silver nitrate is not.

Haemodilution with medium molecular weight hydroxyethyl starch in patients with peripheral arterial occlusive disease stage IIb

The basic therapy of peripheral arterial occlusive disease stage IIb, according to Fontaine, is exercise. It should be determined whether a mild hypervolaemic haemodilution with hydroxyethyl starch or Ringer lactate can produce a further increase in walking distance. For this purpose, three groups of 25 patients each were formed. One group exercised three times weekly and the second group, in addition to exercise, underwent a mild hypervolaemic to isovolaemic dilution therapy with HES for a period of 6 weeks. In the final group the haematocrit was reduced to the same extent by venesections and volume substitution using Ringer lactate. The walking distance in the HES group increased from 216 m to 311 m (44%), in the Ringer lactate group from 214 m to 258 m (20%), and in the exercise group from 213 m to 242 m (14%). On comparison of the groups, the increase in pain-free walking distance in the HES group differs significantly (P less than 0.05) from that achieved in the other groups. It was demonstrated that haemodilution with HES in combination with exercise brings about a clinical effect three times that achieved by exercise alone. Venesection with subsequent administration of Ringer lactate and exercise is superior to exercise alone but markedly inferior to the combination therapy with HES.

Comparison of dextran 40 with albumin and Ringer's lactate as components of perfusion prime for cardiopulmonary bypass in patients undergoing myocardial revascularization

A major expense for the conduct of cardiopulmonary bypass in many institutions is the cost of 5% albumin. Potential advantages in using dextran 40 as the colloid component of the priming solution for cardiopulmonary bypass include decreased cost and less viscosity in the microcirculation. Possible disadvantages include bleeding and anaphylactic reactions. From August 1985 to February 1986, 60 consecutive patients undergoing elective myocardial revascularization were prospectively randomized to receive either 5% albumin ( N = 29) or dextran 40 (N = 31) as the colloid component of the priming solution for cardiopulmonary bypass. Twenty matched patients also underwent revascularization with the prime consisting only of Ringer's lactate solution. There were no differences among the three groups for age, sex, size, crossclamp time, cardiopulmonary bypass time or number of coronary artery bypass grafts performed. In all three groups important postoperative changes were noted in platelet count, bleeding time, thrombin time, prothrombin time, fibrinogen and fibrin split products. Complement levels (C5a) were elevated in the dextran group (p = 0.03). Postoperative crystalloid (p = 0.04) and colloid (p = 0.0001 ) requirements were increased in the Ringer's lactate group and there was a significant weight gain (p = 0.0001). Colloid osmotic pressure was highest in the dextran group during (p = 0.0001) and after bypass (p = 0.001). There was no difference in clinical events and no hospital deaths. In conclusion, we found dextran to be a safe colloid for use as prime in uncomplicated coronary artery bypass grafting patients. The cost of dextran prime was substantially less than for albumin prime. A purely crystalloid prime is discouraged because of a tendency for fluid retention.

The effect of intraperitoneal progesterone on postoperative adhesion formation in rabbits

The immunosuppressive and anti-inflammatory properties of progesterone (P) have been established. The authors investigated whether the intraperitoneal instillation of P would lessen postoperative adhesion formation in New Zealand white rabbits undergoing pelvic surgical procedures. In phase I, severe, peritoneal lesions were made in the right uterine horn (n = 48). Animals were randomized to receive equal volumes of either (1) Ringer's lactate (RL); (2) 32% dextran 70 (HY; Hyskon Division, Pharmacia, Piscataway, NJ); (3) 500 mg P in oil (PO); or (4) 500 mg aqueous P (PA) at initial laparotomy. In phase II, the distal right uterine horn, including the mesosalpinx, was excised and microsurgical anastomosis was accomplished (n = 45). Aqueous P was not used in phase II; otherwise, the same agents were tested. Six weeks later, the severity of the adhesions formed was graded. The mean adhesion scores for the RL and HY groups were low for the right side in both phases and did not differ (P greater than 0.05). In contrast, higher scores were observed in all the P groups, regardless of the P preparation used or the surgical procedure performed (P less than 0.05).

Response of extravascular lung water to intraoperative fluids.

The effect of Ringer's Lactate (RL) and a colloid containing salt solution Plasmanate (PL) on extravascular lung water (EVLW) during aortic surgery was evaluated in a prospective study of 18 patients. Measured blood loss was replaced with packed red blood cells. In addition to red blood cell replacement, either RL or PL was infused (1) to maintain the cardiac output (CO) equal to or greater than the preoperative value, (2) to maintain the pulmonary capillary wedge pressure (PCWP) plus or minus 2 mmHg of preoperative values, and (3) to keep the urinary output greater than or equal to 30 cc/hr. Cardiac output, EVLW, PCWP, serum colloid osmotic pressure (COP), and intrapulmonary shunt fraction (Qs/Qt) were measured serially. All baseline values were similar between groups. The groups were well matched for age, associated disease, operating time, blood loss, and blood transfusions. During operation, the RL group required two times the rate of infusion of the PL group. Urine flow rates were similar on the day of surgery, but by postoperative days one and two, the PL group had approximately one-half of the urine flow rate compared to the RL group. Cardiac output and Qs/Qt increased in both groups. EVLW did not change after operation in either group, despite marked decrease in COP in the RL group. These data indicate that crystalloid resuscitation to physiologic endpoints does not increase extravascular lung water. Thus, manipulation of COP by PL was unnecessary in these patients.

Crystalloid Vs. Colloid Resuscitation

The effects of hemodynamic resuscitation with protein-containing or balanced salt solution were studied prospectively in 29 patients undergoing abdominal aortic surgery. Blood loss was replaced with packed red cells and extracellular volume with either Ringer's Lactate (RL) or 5% albumin in Ringer's lactate (ALB). Fluids were given to maintain the pulmonary capillary wedge pressure (PCWP) equal to or within 5 torr above preoperative (PO) levels, the cardiac output (CO) equal to or greater than preoperative values, and the urine output at least 50 ml/hr. Serum colloid osmotic pressure (COP), CO, PCWP, the gradient between COP and PCWP (COP-PCWP), and intrapulmonary shunt (Qs/Qt) were measured PO, intraoperatively (IO), and daily for 3 days. The measured variables were similar PO in both groups. Operation time, estimated blood loss, and transfusions were similar. Total fluids received for resuscitation (day of operation) was 11.3 +/- 0.8 liters (RL) and 6.2 +/- 0.4 liters (ALB). Fluid balance at the end of resuscitation was 8.4 +/- 0.8 liters (RL) and 3.4 +/- 0.5 liters (ALB). Maximum decrease in COP was 40% (P less than 0.001) in the RL group and was insignificant in the ALB group. The COP-PCWP decreased from 11 +/- 1 to 2 +/- 1 in RL (P less than 0.001) and insignificantly in ALB. Qs/Qt increased slightly in both groups following operation but was not different between groups. Fluid balance, total fluid infused, sodium balance, total sodium infused, COP, or COP-PCWP did not significantly correlate with Qs/Qt. Two patients in the ALB group experienced pulmonary edema associated with normal COPs and elevated PCWPs. There were no cases of pulmonary edema associated with low COPs and normal PCWPs in the crystalloid group. These data seriously question the necessity to maintain COP by using protein-containing solutions during acute hemodynamic resuscitation. When titrated to physiological end points, even large volumes of balanced salt solutions are tolerated well.

Water and protein movement in the sheep lung after septic shock: Effect of colloid versus crystalloid resuscitation

The pulmonary effects of colloid vs crystalloid solutions in resuscitation from septic shock remain controversial. Previous work by us showed increased albumin extravasation in the lung and increased mortality in baboons resuscitated with plasmanate (PL) compared to Ringer's lactate (RL). The present experiments were done using the Staub sheep model to provide correlation of pulmonary lymph flow and lymph protein concentration with hemodynamic and lung water changes. Seventeen sheep were studied; 5 were controls and 12 received 5 × 10 8 organisms per kilogram live E. coli intravenously and were observed for a 2-hr shock period followed by a 2-hr resuscitation period. PL or RL was administered in sufficient volume to maintain left atrial pressure at 12 cm H 2O. Pulmonary, left atrial, systemic arterial, and venous pressures, extravascular lung water (EVLW), pulmonary lymph flow ( Q ̇ L ), and lymph (L Alb) and plasma albumin (P Alb) concentrations were measured every 30 min during shock and resuscitation. Microvascular pressure ( P mv) was calculated. Q ̇ L and P mv did not differ in the PL and RL groups. Q ̇ L was directly proportional to P mv in all animals, indicating that resistance to lymph flow is constant and independent of P mv or treatment regimen. P Alb, L Alb, L Alb flux, and EVLW were significantly different ( P < 0.05) during the resuscitation period in the two groups and showed parallel changes. We conclude that EVLW following resuscitation from sepsis is increased with PL vs RL and that this results from increased plasma and lymph albumin concentrations and increased pulmonary interstitial albumin flux. No evidence of increased permeability to albumin was found during this acute experiment. Q ̇ L did not differ in the PL and RL groups and did not contribute to the increased edema in the PL group.

Effects of large volume-hemodilution perfusion on plasma volume, plasma proteins and plasma electrolytes in neonatal piglets.

Two groups of 15 neonatal piglets underwent arteriovenous perfusion with the chest closed, at normothermia and without an oxygenator in the system until complete mixing of the blood and priming fluid was accomplished. The extracorporeal circuit was primed in one group with a warm (38 °C) buffered Ringer-lactate solution, and in the second group with an equally warm buffered solution of 2% Rheomacrodex in Ringer-lactate. The priming volumes of the perfused animals were individually tailored to result in a mixed (blood and priming solution) hematocrit of 22%. A control group of 15 piglets underwent the same surgical procedures but were not perfused. Large vessel hematocrit, plasma volume, the five major plasma protein components, plasma electrolytes and plasma osmolarity were measured before perfusion, immediately after and every 8 h for a period of 24 h. During perfusion, plasma volume, erythrocytes, and proteins were lost from the circulation. Plasma osmolarities showed larger fluctuations in the Rheomacrodex group than in the Ringer-lactate group. The neonatal pig is able to cope with large volume hemodilution resulting in a hematocrit of 22%. It shows a well-developed regulatory mechanism to counteract plasma volume and plasma protein losses; the replenishment of plasma volume and restoration of each major circulating plasma protein fraction, except γ-globulin, are accomplished in about 24 h. The restoration of plasma volume occurs faster than the restoration of plasma proteins, but when dextran is present the reverse is the case. Since the restoration of plasma volume, plasma proteins, and red blood cells do not show the same patterns, sequestration of whole blood is unlikely. 2% Rheomacrodex in Ringer-lactate appears to enhance protein restoration considerably.