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The role of hypertonic saline in sepsis remains unclear because clinical data are limited and the balance between beneficial and adverse effects is not well defined. In this systematic literature review, we searched PubMed and Embase to identify all randomized controlled trials up until January 31, 2018 in which hypertonic saline solutions of any concentration were used in patients of all ages with sepsis and compared to a cohort of patients receiving an isotonic fluid. We identified 8 randomized controlled trials with 381 patients who had received hypertonic saline. Lower volumes of hypertonic saline than of isotonic solutions were needed to achieve the desired hemodynamic goals (standardized mean difference, -0.702; 95% CI, -1.066 to -0.337; P < .001; moderate-quality evidence). Hypertonic saline administration was associated with a transient increase in sodium and chloride concentrations without adverse effects on renal function (moderate-quality evidence). Some data suggested a beneficial effect of hypertonic saline solutions on some hemodynamic parameters and the immunomodulatory profile (very low-quality evidence). Mortality rates were not significantly different with hypertonic saline than with other fluids (odds ratio, 0.946; 95% CI, 0.688-1.301; P = .733; low-quality evidence). In conclusion, in our meta-analysis of studies in patients with sepsis, hypertonic saline reduced the volume of fluid needed to achieve the same hemodynamic targets but did not affect survival.

Prothrombin complex concentrates (PCCs) have been associated with a possible risk of thromboembolic complications, potentially attributable to an increased ratio of the plasma concentration of factor II (FII) to antithrombin (AT). We developed a mathematical model to examine the relationship between amounts of PCC or therapeutic plasma administered, and plasma levels of FII and AT. The model showed that PCC produces substantial increases in plasma levels of FII but only small changes in AT, increasing the FII:AT ratio. Therapeutic plasma was shown to have only modest effects on levels of FII or AT, unless high doses are used.

Background: Crystalloids are used routinely for perioperative fluid management in cesarean delivery. Few studies have determined the crystalloid of choice in obstetric anesthesia. We compared the effects of Ringer's lactate (RL) versus 0.9% normal saline (NS) on maternal and neonatal blood pH and 24-hour postoperative morbidity in urgent cesarean delivery in a low-resource setting. Our hypothesis was that RL would result in 30% less acidosis than NS., Methods: This was a pragmatic prospective double-blind randomized controlled trial in the Mulago National Referral Hospital Labor Ward Theater from September 2011 to May 2012. Five hundred parturients were studied; 252 were randomly assigned to NS and 248 to RL groups. Preoperative and postoperative maternal venous blood gases and placental umbilical arterial cord blood gases were analyzed. The primary outcome was incidence of maternal acidosis, as defined by a postoperative drop in venous pH below 7.32 or reduction in base excess below -3 in a previously normal parturient. Maternal 24-hour postoperative morbidity, neonatal pH, and neonatal base excess were the main secondary outcomes. The study was registered in ClinicalTrials.gov as NCT01585740., Results: The overall incidence of maternal acidosis was 38% in NS and 29% in RL (relative risk, 1.29; 95% confidence interval, 1.01-1.66; P = .04). Thirty-two percent of parturients in NS experienced a drop in venous pH below 7.32 postoperatively, compared with 19% in RL (relative risk, 1.65; 95% confidence interval, 1.18-2.31; P = .003). The comparative drop in base excess postoperatively below -3 between the 2 groups was not statistically significant. There were no significant differences in the incidence of maternal 24-hour postoperative morbidity events and neonatal outcomes between the 2 groups., Conclusions: NS may be a safe choice for intraoperative fluid therapy in urgent cesarean delivery as RL, albeit with an increased incidence of metabolic acidosis.

Background: Positive fluid balance has been associated with worse outcomes, and knowledge of differences in the amounts of different types of fluid needed to achieve the same end points may have important clinical implications. Large molecules persist longer in the blood vessels than smaller molecules, such that less IV colloid may be needed to achieve similar hemodynamic end points compared with crystalloid. Recent clinical data have, however, challenged this physiological concept, with investigators reporting lower-than-expected crystalloid/colloid ratios in various populations., Methods: We performed a systematic search in MEDLINE, EMBASE, and CENTRAL up to December 18, 2013, to retrieve all studies comparing (any) crystalloid with (any) colloid in all types of patients. The crystalloid/colloid ratio was calculated for each study. Descriptive analysis was performed for all studies, and a meta-analysis was performed in those studies reporting full data (in terms of means and standard deviations) of infused fluid volumes. Studies were grouped according to study and population characteristics. A meta-regression analysis was then performed to evaluate some of the possible reasons for differences in crystalloid/colloid ratios across studies., Results: From 976 studies, 48 were retained for the final analysis; 24 of the studies had sufficient data for meta-analysis. The crystalloid/colloid ratio across all the studies included in the meta-analysis was 1.5 (95% confidence interval, 1.36-1.65) with marked heterogeneity among studies (I = 94%). From the meta-regression analysis, decade of publication across all publications (P = 0.001) and concentration (tonicity) in the subgroup of albumin studies (P = 0.001) were associated with the administered crystalloid/colloid ratio. The reduction in heterogeneity among studies for all publications in the meta-regression was minimal, with the maximal decrease obtained when decade of publication was considered (R = 12%)., Conclusions: Greater fluid volumes are required to meet the same targets with crystalloids than with colloids, with an estimated ratio of 1.5 (1.36-1.65), but there is marked heterogeneity among studies. The crystalloid/colloid ratio seems to have decreased over the years, and differences in ratios are correlated with the concentration of albumin solutions; however, the main reasons behind the high heterogeneity among studies remain unclear.

Background: Recent studies have shown a decline in glomerular filtration rate and increased renal vasoconstriction after administration of normal saline when compared with IV solutions with less chloride. In this study, we investigated the impact of normal saline versus a chloride-reduced, acetate-buffered crystalloid on the incidence of hyperkalemia during cadaveric renal transplantation. The incidence of metabolic acidosis and kidney function were secondary aims., Methods: In this prospective randomized controlled trial, 150 patients received normal saline or an acetate-buffered balanced crystalloid during and after cadaveric renal transplantation. Venous blood gases were obtained at the start of anesthesia and every 30 minutes until discharge from the postoperative surveillance unit. Serum creatinine and 24-hour urine output were obtained on postoperative days 1, 3, and 7., Results: Patients received a similar amount of fluid (median: 2625mL [interquartile range: 2000 to 3100] vs 2500 mL [2000 to 3050], P = 0.83). Hyperkalemia, defined as serum potassium >5.9 mmol/L, occurred in 13 patients (17%) in the saline and 15 (21%) in the balanced group (P = 0.56; difference between proportions -0.037 [-16.5% to 8.9%]). Minimum base excess was lower in the saline group compared with the balanced regimen (-4.5 mmol/L [-6 to -2.4] vs -2.6 mmol/L [-4 to -1], P < 0.001) and maximum chloride was significantly higher in the saline group (109 mmol/L [107 to 111] vs 107 mmol/L [105 to 109], P < 0.001). No difference in creatinine or urine output was seen postoperatively. Significantly more patients needed catecholamines in the saline group (30% vs 15%, P = 0.03)., Conclusions: The incidence of hyperkalemia differed by less than 17% between groups. Use of balanced crystalloid resulted in less hyperchloremia and metabolic acidosis. Significantly more patients in the saline group required administration of catecholamines for circulatory support.

Despite evidence from clinical studies and meta-analyses that resuscitation with colloids or crystalloids is equally effective in critically ill patients, and despite reports from high-quality clinical trials and meta-analyses regarding nephrotoxic effects, increased risk of bleeding, and a trend toward higher mortality in these patients after the use of hydroxyethyl starch (HES) solutions, colloids remain popular and the use of HES solutions is increasing worldwide. We investigated the major rationales for colloid use, namely that colloids are more effective plasma expanders than crystalloids, that synthetic colloids are as safe as albumin, that HES solutions have the best risk/benefit profile among the synthetic colloids, and that the third-generation HES 130/0.4 has fewer adverse effects than older starches. Evidence from clinical studies shows that comparable resuscitation is achieved with considerably less crystalloid volumes than frequently suggested, namely, <2-fold the volume of colloids. Albumin is safe in intensive care unit patients except in patients with closed head injury. All synthetic colloids, namely, dextran, gelatin, and HES have dose-related side effects, which are coagulopathy, renal failure, and tissue storage. In patients with severe sepsis, higher doses of HES may be associated with excess mortality. The assumption that third-generation HES 130/0.4 has fewer adverse effects is yet unproven. Clinical trials on HES 130/0.4 have notable shortcomings. Mostly, they were not performed in intensive care unit or emergency department patients, had short observation periods of 24 to 48 hours, used cumulative doses below 1 daily dose limit (50 mL/kg), and used unsuitable control fluids such as other HES solutions or gelatins. In conclusion, the preferred use of colloidal solutions for resuscitation of patients with acute hypovolemia is based on rationales that are not supported by clinical evidence. Synthetic colloids are not superior in critically ill adults and children but must be considered harmful depending on the cumulative dose administered. Safe threshold doses need to be determined in studies in high-risk patients and observation periods of 90 days. Such studies on HES 130/0.4 are still lacking despite its widespread and increasing use. Because there are safer and equally effective alternatives in the form of crystalloids, use of synthetic colloids should be avoided except in the context of clinical studies.

Background: Early graft function is crucial for successful kidney transplantation. Maintaining adequate hydration is complicated by rapid movement of water to the extravascular space. We designed this study to test the effect of maximal hydration during graft ischemia time on early renal function., Methods: Forty adult patients with chronic renal failure underwent renal transplantation from related living donors. Study subjects were randomly assigned 1 of 2 regimens for intraoperative hydration. The constant infusion rate group received normal saline 0.9% at an infusion rate 10 to 12 mL . kg(-1) . h(-1) from the start of surgery until the renal vessels were unclamped after vascular anastomosis. The central venous pressure target (CVPT) group received normal saline 0.9% titrated to maintain a specific central venous pressure (CVP). The target CVP from the start of surgery until clamping of the donor renal vessels was 5 mm Hg except for the interval from clamping of the renal vessels until the end of renal vascular anastomosis, when the target CVP was 15 mm Hg. Perioperative hemodynamics, infused saline volumes, rate of infusion, onset of diuresis, graft turgidity, urine volume, and renal function during the first 5 postoperative days were recorded., Results: At the end of renal ischemia time, both groups had received approximately 3 L crystalloid solution. The CVPT group achieved the highest peak of intravascular volume expansion with an average infusion rate of 48.3 mL . min(-1) during 48 +/- 12 minutes of renal ischemia. The CVPT group had better graft function, required fewer vasopressors and diuretics, and had less postoperative tissue edema than the constant infusion rate group., Conclusions: Hydration directed toward maintaining a given CVP during kidney transplantation produced a more stable hemodynamic profile and promoted diuresis. The calculated infusion rate of approximately 45 to 50 mL . min(-1), within an hour ischemia time, seems feasible to enhance early graft function. A larger trial with long-term follow-up of renal function is warranted to confirm the clinical benefit of titrating IV crystalloid administration to maintain a given CVP in this population.

Background: Hypotension after spinal anesthesia for cesarean delivery remains a major clinical problem. Fluid preloading regimens together with vasopressors have been used to reduce its incidence. Previous studies have used noninvasive arterial blood pressure measurement and vasopressor requirements to evaluate the effect of preload. We used a suprasternal Doppler flow technique to measure maternal cardiac output (CO) and corrected flow time (FTc, a measure of intravascular volume) before and after spinal anesthesia after 3 fluid preload regimens. We hypothesized that colloid solutions, compared with crystalloid, would produce the largest increase in CO and have the lowest incidence of hypotension., Methods: Sixty healthy term women scheduled for planned cesarean delivery under spinal anesthesia were recruited for this randomized, double-blind study. Baseline heart rate, systolic blood pressure (SBP), CO, and FTc were recorded in the left lateral tilt position. Patients were randomized to receive 1 of 3 fluid preload regimens given over 15 min: 1.5 L crystalloid (Hartman's solution), 0.5 L of 6% w/v hydroxyethyl starch (HES) solution (HES 0.5), or 1 L of 6% w/v HES solution (HES 1.0). Further measurements were made after fluid loading every 5 min for 30 min. After 30 min, spinal anesthesia was induced with hyperbaric bupivacaine 12.5 mg with fentanyl 15 microg and recordings were continued every 5 min for 20 min or until surgery started. The primary outcome, CO, was compared among groups. The incidence of hypotension (defined as a 20% reduction in SBP from the baseline), ephedrine use, and umbilical cord blood gases were also compared., Results: Patient characteristics, heart rate, SBP, and cord gases were similar among groups. Although CO and FTc increased after preload in all groups (P < 0.005), this was only maintained with HES 1.0 after spinal anesthesia (P < 0.005). There were no differences among groups in the incidence of hypotension (70% vs 35% vs 65% for Hartman's solution, HES 0.5, and HES 1.0, respectively; P = 0.069) or mean ephedrine dose (10.4 vs 5.7 vs 9.7 mg; P = 0.26)., Conclusion: Despite CO and FTc increases after fluid preload, particularly with HES 1.0 L, hypotension still occurred. The data suggest that CO increases after these preload regimens cannot compensate for reductions in arterial blood pressure after spinal anesthesia.

Background: Recent studies have emphasized the importance of perioperative fluid restriction. However, fluid restriction regimens may increase the likelihood of insufficient perioperative fluid administration or may result in excess intravascular crystalloid replacement. We postulate that the use of transesophageal echocardiography may reduce the amount of crystalloid administered during open and laparoscopic colorectal surgery., Methods: Fifteen ASA I and II patients scheduled for open colorectal surgery, and 15 patients scheduled for laparoscopic surgery were studied. Lactated Ringer's solution was infused during the procedures. Left ventricular end diastolic volume index (LVEDVI) and cardiac index were assessed throughout surgery and used to guide the rate of lactated Ringer's solution administration. Statistical analysis was performed with Student's t-test for unpaired samples., Results: The rate of crystalloid administration required to maintain baseline LVEDVI and cardiac index was 5.9 +/- 2 mL x kg(-1) x h(-1) for open surgery and 3.4 +/- 0.8 mL x kg(-1) x h(-1) for laparoscopic surgery (P < 0.01). This slower rate for laparoscopic surgery was offset by the longer surgical duration., Conclusion: The rate of crystalloid solution to maintain baseline LVEDVI and cardiac index was greater in open surgery than laparoscopic surgery, and lower than commonly recommended for colorectal surgery.

Background: Low tissue oxygen tension is an important factor leading to the development of wound dehiscence and anastomotic leakage after colon surgery. We tested whether supplemental fluid and supplemental oxygen can increase tissue oxygen tension in healthy and injured, perianastomotic, and anastomotic colon in an acutely instrumented pig model of anastomosis surgery., Methods: Sixteen Swiss Landrace pigs were anesthetized (isoflurane 0.8%-1%) and their lungs ventilated. The animals were randomly assigned to low fluid treatment ("low" group, 3 mL x kg(-1) x h(-1) lactated Ringer's solution) or high fluid treatment ("high" group, 10 mL/kg bolus, 18 mL x kg(-1) x h(-1) lactated Ringer's solution) during colon anastomosis surgery and a subsequent measurement period (4 h). Two-and-half hours after surgery, tissue oxygen tension was recorded for 30 min during ventilation with 30% oxygen. Three hours after surgery, the animals' lungs were ventilated with 100% oxygen for 60 min. Tissue oxygen tension was recorded in the last 30 min. Tissue oxygen tension was measured with polarographic Clark-type electrodes, positioned in healthy colonic wall, close (2 cm) to the anastomosis, and in the anastomosis., Results: In every group, tissue oxygen tension during ventilation with 100% oxygen was approximately twice as high as during ventilation with 30% oxygen, a statistically significant result. High or low volume crystalloid fluid treatment had no effect on colon tissue oxygen tension., Conclusions: Supplemental oxygen, but not supplemental crystalloid fluid, increased tissue oxygen tension in healthy, perianastomotic, and anastomotic colon tissue.

Small volumes of hypertonic saline solution ([HS] 7.5% NaCl) produce systemic and microcirculatory benefits in hemorrhaged animals. Pentoxifylline (PTX) has beneficial effects when administrated after hemorrhagic shock. We tested the hypothesis that the combination of HS and PTX in the initial treatment of hemorrhagic shock provides synergistic hemodynamic benefits. Twenty-four dogs were bled to a target arterial blood pressure of 40 mm Hg and randomized into 3 groups: lactated Ringer's solution (33 mL/kg; n = 6); HS (7.5% NaCl 4 mL/kg; n = 9); and HS+PTX (7.5% NaCl 4 mL/kg + PTX 15 mg/kg; n = 9). Systemic hemodynamics were measured by Swan-Ganz and arterial catheters. Gastric mucosal-arterial Pco2 gradient (D(g-a)Pco2; gas tonometry), portal vein blood flow (ultrasonic flowprobe), and systemic and regional O2-derived variables were also evaluated. HS induced a partial increase in mean arterial blood pressure, cardiac output, and portal vein blood flow. In the HS+PTX group, we observed a significant, but transitory, increase in systemic oxygen delivery (180 +/- 17 versus 141 +/- 13 mL/min) in comparison to HS alone. PTX infusion during hypertonic resuscitation promoted a significant reduction in D(g-a)Pco2 (41.8 +/- 4.8 to 25.7 +/- 3.9 mm Hg) when compared with isolated HS infusion (48.2 +/- 6.4 to 39.4 +/- 5.5 mm Hg). We conclude that PTX as an adjunct drug during hypertonic resuscitation improves cardiovascular performance and gastric mucosal oxygenation.

Several controlled, experimental, hypotensive models of hemorrhagic shock have evaluated the effects of timing, rate, and types of fluid replacement. In a near-fatal experimental model we evaluated the hemodynamic and metabolic effects of two types of solutions for fluid resuscitation. In this study, 30 young Large-White pigs were randomly assigned to three groups: Group I (control, n= 10), not bled; Group II (hydroxyethyl starch, HES, n = 10), submitted to controlled hemorrhage to a mean arterial blood pressure (MAP) of 30 mmHg and blood lactate >10 mM/L, at which time resuscitation was initiated with 7 mL/kg of HES 130/0.4 6% followed by 33 mL/kg of lactated Ringer's solution (LR) and retransfusion; Group III (LR, n = 10), submitted to controlled hemorrhage to a MAP of 30 mmHg and blood lactate >10 mM/L, at which time resuscitation was initiated with 40 mL/kg of LR followed by retransfusion. The resuscitation with HES 130/0.4 proved to be superior to LR, expressed by hemodynamic and perfusion variables. Despite improvement in tissue perfusion, MAP did not totally return to baseline values. In conclusion, early colloid infusion resulted in prompt recovery of tissue perfusion when compared with infusion with an equal volume of crystalloid.

Unlabelled: Although the distribution of various crystalloid and colloid solutions at equilibrium has been well established, the acute peak expansion of intravascular volume that can be achieved with the rapid administration of crystalloid or colloid is unknown. We studied eight healthy male subjects in a two-part crossover trial designed to assess the maximal increase in intravascular volume achieved with 1000 mL of lactated Ringer's solution compared with the same volume of 6% Hetastarch. Subjects were made moderately hypovolemic by the withdrawal of 900 mL of blood, and then the crystalloid or colloid solution was rapidly infused over 5-7 min. Serial dilution of hematocrit was measured every 5 min for 30 min to determine changes in blood volume. Peak expansion of intravascular volume with lactated Ringer's solution was 630 +/- 127 mL, occurring immediately the rapid infusion was complete, whereas the peak expansion of intravascular volume with 6% Hetastarch was 1123 +/- 116 mL and occurred 5 min after the completion of the fluid infusion. The results were significantly different (P < 0.001). These results would suggest that even for very short periods of time, rapid infusion of colloid significantly more effectively increases blood volume and, by inference, cardiac output than the same volume of crystalloid, even if the crystalloid is administered very rapidly., Implications: Under conditions of moderate hypovolemia, the maximal acute intravascular volume expansion with the rapid infusion of 1000 mL of lactated Ringer's solution is slightly more than half that achieved with the same volume of 6% Hetastarch.

Unlabelled: In this randomized, controlled study in dogs, we examined the short-term effects of blood pressure targeted fluid resuscitation with colloids or crystalloids solutions on systemic oxygen delivery, and lactate blood concentration. Fluid resuscitation using hydroxyethyl starch (HES) 6% to a mean arterial blood pressure (MAP) of 60 mm Hg was compared with lactated Ringer's solution (LR) to a MAP of 60 or 80 mm Hg (LR60 and LR80, respectively). The model was one of withdrawal of blood to a MAP of 40 mm Hg through an arterial catheter that was then connected to a system allowing bleeding to occur throughout the study whenever MAP exceeded 40 mm Hg. Target MAP was maintained for 60 min with a continuous infusion of the designated fluid replacement. All 15 dogs (5 in each group) survived until the last measurement. Blood loss in the LR80 group (2980 +/- 503 mL) (all values mean +/- SD) was larger than in the LR60 and HES60 groups (1800 +/- 389 mL, and 1820 +/- 219 mL, respectively) (P < 0.001). Whereas 840 +/- 219 mL of HES60 was needed to maintain target MAP, 1880 +/- 425 mL of LR was needed in the LR60 group, and 4590 +/- 930 mL in the LR80 group (P < 0.001). Lactate blood concentrations were smaller and delivered O(2) higher in the HES60 group (35 +/- 17 mg/dL and 239 +/- 61 mL/min, respectively) in comparison to the LR60 group (89 +/- 18 mg/dL and 140 +/- 48 mL/min, respectively) and the LR80 group (75 +/- 23 mg/dL and 153 +/- 17 mL/min, respectively) (P = 0.02 and P = 0.026). In conclusion, fluid resuscitation during uncontrolled bleeding, to a target MAP of 60 mm Hg, using HES60 resulted in larger oxygen delivery and smaller systemic lactate A resuscitation to a target MAP of 60 or 80 mm Hg using LR., Implications: Fluid resuscitation to a target mean arterial blood pressure of 60 mm Hg during uncontrolled bleeding resulted in larger oxygen delivery and smaller systemic lactate concentrations when hydroxyethyl starch 6% was used, in comparison to lactated Ringer's solution resuscitation to a target mean arterial blood pressure of 60 or 80 mm Hg.

Unlabelled: To evaluate the influence of acute isovolemic hemodilution on the dose-response and time course of action of vecuronium, we studied 60 adult patients with and without hemodilution during surgery. The patients with hemodilution underwent major elective plastic surgery with an anticipated surgical loss of more than 600 mL. Anesthesia was induced with thiopental 4-6 mg/kg and fentanyl 2-4 microg/kg i.v. and was maintained with 60% nitrous oxide in oxygen. Further increments of thiopental 2 mg/kg or fentanyl 2 microg/kg were given as required. Acute isovolemic hemodilution in the hemodilution group was induced by drainage of venous blood and an i.v. infusion of lactated Ringer's solution and 6% dextran, during which hematocrit and hemoglobin decreased from 45.7% to 26.2% and from 148.5 g/L to 90.2 g/L, respectively. Neuromuscular function was assessed mechanomyographically with train-of-four stimulation at the wrist every 12 s, and the percent depression of T1 response was used as the study parameter. The dose-response relationships of vecuronium in the two groups were determined by using the cumulative dose-response technique. The results showed that during hemodilution, the dose-response curve of vecuronium was shifted to the left in a parallel fashion, and the potency of vecuronium was increased. There were significant differences in the 50%, 90%, and 95% effective doses between the two groups. After the i.v. administration of vecuronium 80 microg/kg, vecuronium-induced neuromuscular block was significantly longer in the patients with hemodilution than in the control patients. The duration of peak effect, clinical duration, recovery index, and total duration in the hemodilution patients were significantly different from those in the control patients. We conclude that hemodilution induces significant changes in the pharmacodynamics of vecuronium., Implications: We found that patients with hemodilution were 20% more sensitive to vecuronium and had a longer duration of action after the administration of the same dose than the controls. This should be taken into account when vecuronium is used as a muscle relaxant during acute hemodilution.

Unlabelled: None of the natural and synthetic colloids currently available is free from the risk of side effects. This study was performed to contribute to the epidemiology of adverse reactions of the widely used 200/0.5 hydroxyethyl starch 6% solution (HES). Study end points were anaphylactoid reactions during preanesthesia infusion and perioperative course, and pruritus 5 days postoperatively (clinical examination and inquiry) and 8 wk after application (mailed patient questionnaire). We consecutively randomized 750 patients undergoing minor elective surgery into two parallel groups treated with HES (from two different manufacturers) and one control group treated with lactated Ringer's solution. The study population was well matched among the groups and consisted of patients of both sexes, aged 18-95 yr, ASA physical status I-III. No drug-related anaphylactoid reactions were detected during either of the observation intervals. There was no episode of pruritus after the fifth postoperative day. Incidence of pruritus after 8 wk was quite frequent but not significantly different (chi2 test, P = 0.77): 9.1% and 12.0% in the two HES groups and 11.5% in the lactated Ringer's solution control group. Except for pruritus, we conclude that HES was associated with no more complications than lactated Ringer's solution., Implications: Anaphylactoid reactions and pruritus (itching) after the administration of a 6% hydroxyethyl starch (200/0.5) versus lactated Ringer's solution were assessed in a prospective, randomized, controlled study. There were no differences, although there was a more than 10% incidence of pruritus in both groups.

The practice of routinely prehydrating patients by infusing a crystalloid or colloid solution (up to 1.0 L/70 kg) for prevention of spinal anesthesia-induced hypotension has been challenged recently, after several reports of failure to demonstrate its efficacy in young women. We compared the incidence and frequency of hypotension and vasopressor therapy after spinal anesthesia and no prehydration with crystalloid and colloid prehydration in elderly patients. Eighty-five ASA grade I or II patients (aged 60-89 yr) for elective total hip replacement were randomized to receive 500 mL crystalloid solution (Hartmanns, n = 29), 500 mL colloid (Haemaccel, n = 28), or no prehydration (n = 28) over 10 min prior to spinal anesthesia. Hypotension was defined as a 30% decrease from baseline systolic blood pressure (BP) or systolic < 90 mm Hg, and was treated with ephedrine 3-mg boluses. Although absolute systolic BP readings were significantly higher in the colloid group between 6 and 30 min (P < 0.05), the incidence of hypotension was not significantly different between the groups. The incidence of ephedrine use, incidence of nausea/vomiting, and median total dose of ephedrine were similar in all groups. We conclude that, in elderly patients undergoing elective procedures, withholding prehydration is not associated with any greater degree of hypotension or need for vasopressor therapy compared with crystalloid or colloid prehydration.

Resuscitation using small volumes (3-5 mL/kg) of 7.5% hypertonic saline (HTS) is effective for hemorrhagic shock. Whether HTS is beneficial for the initial resuscitation of burn injury is not clear. We compared the hemodynamic effects of HTS versus lactated Ringer's solution (LR) and examined organ tissue perfusion during burn resuscitation (R). Full thickness scald burn (35% of total body surface area) was induced in pentobarbital-anesthetized rats. Regional blood flows were measured using radioactive microspheres before and 30 min after burn, and after R with either HTS (4 mL/kg) or LR (at a dose required for equivalent restoration of arterial blood pressure). Data from the HTS-or LR-resuscitated groups were compared to those from a nonresuscitated group (n = 10 in each group). Mean arterial pressure decreased 30% after burn (from 120 +/- 4 to 84 +/- 5 mm Hg, mean +/- SEM) and returned toward baseline (112 +/- 7 mm Hg) at 10 min after R with HTS (4 mL/kg) or LR (22.6 +/- 0.7 mL/kg), but subsequently decreased to 100 +/- 7 mm Hg with HTS and 105 +/- 5 mm Hg with LR at 30 min. In contrast to LR, resuscitation using HTS was associated with tachycardia. Blood flows to the skin and muscle of the normal or burn regions did not change after fluid resuscitation as compared to a nonresuscitated group. Fluid resuscitation transiently increased intestinal perfusion. Similar improvements in blood flow to the spleen were observed with HTS and LR at 10 min after R (from 128 +/- 10 to 156 +/- 15 and from 113 +/- 10 to 145 +/- 26 mL.min-1 x 100 g-1, respectively). However, at 30 min after R, splenic perfusion in the LR group was not different from that in the nonresuscitated group. Blood flows to the brain and kidney increased 39% and 42%, respectively, with HTS. HTS was also associated with pronounced improvements in blood flows to the heart (from 346 +/- 20 to 631 +/- 37 mL.min-1 x 100 g-1), liver (from 36 +/- 2 to 62 +/- 4 mL.min-1 x 100 g-1), and testis (from 29 +/- 2 to 43 +/- 2 mL.min-1 x 100g-1). Resuscitation using HTS was associated with rapid improvement in organ tissue perfusion in anesthetized rats subjected to burn injury. In comparison to LR, greater increases in blood flows to the heart, kidney, liver, and testis were observed with HTS. The results suggest that significant improvement in blood flow distribution can be achieved using HTS at less than one fifth the volume of LR for the initial treatment of burn shock.

The purpose of this study was to compare the accuracy of conductivity, adjusted conductivity, photometric, and centrifugation methods of measuring or estimating hemoglobin (Hb) with Coulter measured HB as the reference. These bedside methods were studied in 25 cardiac surgery patients during euvolemia and hemodilution and after salvaged autologous red blood cell transfusion. In vivo patient blood samples were obtained before induction, at the start of cardiopulmonary bypass (CPB), after CPB, and after blood transfusion. In 10 patients, blood was sampled in vitro from units of processed blood. Hb values were determined using conductivity by Stat-Crit, adjusted conductivity by Nova Stat Profile 9, bedside photometry by HemoCue, and centrifugation methods. The calculated bias values of Coulter test method Hb (mean +/- SD) for in vivo patient blood samples (n = 90) were: Stat-Crit = 0.6 +/- 0.8 g/dL; Nova Stat Profile 9 = -0.7 +/- 0.4 g/dL; HemoCue = -0.1 +/- 0.2 g/dL; and centrifuge = 0.1 +/- 0.5 g/dL (P < 0.0001). Hb bias values (g/dL) for in vitro samples (n = 10) obtained from processed blood were Stat-Crit = 5.1 +/- 0.6; Nova Stat Profile 9 = 3.0 +2- 0.6; HemoCue = 0.4 +/- 0.4; and centrifuge = 0.6 +/- 0.3 (P < 0.0001). Hb assessment by different test methods may be significantly affected during hemodilution and after blood transfusion. In vitro conditions exaggerated the inaccuracy of conductivity and adjusted conductivity Hb estimates. The rank order of closest approximation to the Coulter measurement for all in vivo blood samples was provided by bedside photometry, followed by centrifugation, adjusted conductivity, and uncorrected conductivity methods.

The purpose of this study was to determine whether Ringer's lactate solution increases extravascular lung water (EVLW) during resuscitation after hemorrhagic shock. Ten sheep anesthetized with thiamylal were bled to a mean arterial pressure (MAP) of 50 mm Hg; further bleeding maintained that pressure for 30 min. Resuscitation fluid consisted of Ringer's lactate solution in volumes necessary to restore and maintain for 1 hr MAP, pulmonary capillary wedge pressure (PCWP), and cardiac index at levels equal to those measured before bleeding. After volume replacement, the colloid oncotic pressure (COP) - PCWP gradient (COP - PCWP) decreased from 12 +/- 3 to 2 +/- 5 mm Hg (P less than 0.001). After volume restoration, COP decreased from 19 +/- 8 mm Hg to 12 +/- 2 mm Hg (P less than 0.001). Despite the large volume of fluid administered, EVLW did not increase. Crystalloid resuscitation does not necessarily increase EVLW despite significant decreases in COP and COP - PCWP gradient.