Effects of albumin and crystalloid priming strategies on red blood cell transfusions in on-pump cardiac surgery: a network meta-analysis.

BACKGROUND: In on-pump cardiac surgery, the albumin priming strategy could maintain colloid osmotic pressure better than crystalloid solutions and reduce excessive perioperative fluid balance. However, a high-quality meta-analysis is required to compare the safety of these approaches in perioperative red blood cell (RBC) transfusions. Owing to limited direct evidence, we conducted a network meta-analysis (NMA) to increase the pool of studies and provide indirect evidence. METHODS: The pre-defined primary outcomes were intraoperative and the first 24 h postoperative RBC transfusion volume in units. The pre-defined secondary outcome was postoperative blood loss (the first 24 h). We reviewed all randomized controlled trials comparing albumin, crystalloid, and artificial colloid priming strategies. Studies that only displayed pre-defined outcomes could be included. A pairwise meta-analysis was performed on studies that directly compared the pre-defined outcomes between albumin and crystalloids. Additionally, a random-effects network meta-analysis (NMA) model was employed to generate indirect evidence for the pre-defined outcomes between albumin and crystalloids. RESULTS: The literature search identified 830 studies,10 of which were included in the final analysis. Direct meta-analysis indicated that crystalloid priming significantly decreased total perioperative RBC transfusions (MD: -0.68U; 95%CI: -1.26, -0.09U; P = 0.02) and intraoperative RBC transfusions (MD: -0.20U; 95%CI: -0.39, -0.01U; P = 0.03) compared to albumin. Postoperative RBC transfusions showed a decreasing trend in the crystalloid group; however, the difference was not statistically significant. (MD: -0.16U; 95%CI: -0.45, 0.14U; P = 0.30). After including indirect evidence, the NMA results continued to demonstrate a higher RBC receiving with the albumin priming strategy compared to crystalloids, although the differences did not reach statistical significance. For postoperative blood loss, direct evidence showed no significant differences between albumin and crystalloid priming strategies. However, NMA evidence displayed that albumin exist higher probability of reducing postoperative blood loss than crystalloid. CONCLUSION: Both direct and NMA evidence indicated that the albumin priming strategy resulted in more perioperative RBC transfusions than crystalloids. Considering the additional blood management burden, the application of an albumin-priming strategy in on-pump cardiac surgery still needs more consideration.

Revisiting the Use of Normal Saline for Peritoneal Washing in Ovarian Cancer.

The omentum is the predominant site of ovarian cancer metastasis, but it is difficult to remove the omentum in its entirety. There is a critical need for effective approaches that minimize the risk of colonization of preserved omental tissues by occult cancer cells. Normal saline (0.9% sodium chloride) is commonly used to wash the peritoneal cavity during ovarian cancer surgery. The omentum has a prodigious ability to absorb fluid in the peritoneal cavity, but the impact of normal saline on the omentum is poorly understood. In this review article, we discuss why normal saline is not a biocompatible solution, drawing insights from clinical investigations of normal saline in fluid resuscitation and from the cytopathologic evaluation of peritoneal washings. We integrate these insights with the unique biology of the omentum and omental metastasis, highlighting the importance of considering the absorptive ability of the omentum when administering agents into the peritoneal cavity. Furthermore, we describe insights from preclinical studies regarding the mechanisms by which normal saline might render the omentum conducive for colonization by cancer cells. Importantly, we discuss the possibility that the risk of colonization of preserved omental tissues might be minimized by using balanced crystalloid solutions for peritoneal washing.

The kinetics of isotonic and hypertonic resuscitation fluids is dependent on the sizes of the body fluid volumes.

Background and Aims: The extracellular and intracellular fluid volumes (ECV and ICV) vary not only with age, gender, and body weight but also with the habitual intake of water. The present study examines whether the baseline variations in the ECV and ICV change the distribution and elimination of subsequently given infusion fluids. Material and Methods: Twenty healthy male volunteers underwent 50 infusion experiments with crystalloid fluid for which the fluid volume kinetics was calculated based on frequent measurements of the hemodilution using mixed-effects modeling software. The results were compared with the ECV and ICV measured with multifrequency bioimpedance analysis before each infusion started. The fluids were given over 30 minutes and comprised 25 mL/kg Ringer's acetate (N = 20), Ringer's lactate, 5 mL/kg 7.5% saline, and 3 mL/kg 7.5% saline in 6% dextran 70 (these fluids, N = 10). Results: A large ICV was associated with a small extravascular accumulation of infused fluid, which increased the plasma volume expansion and the urinary excretion. With hypertonic fluid, a large ECV greatly accelerated urinary excretion. The body weight did not serve as a covariate in the kinetic models. Albumin was recruited to the plasma during infusion of both types of fluid. The hypertonic fluids served as diuretics. The infused excess sodium and osmolality were distributed over a 35% larger space than the sum of the ECV and ICV. Conclusion: A large ICV reduced the rate of distribution of Ringer's solution, whereas a large ECV accelerated the excretion of hypertonic saline.

Balanced Salt Solutions for Critically Ill Patients: Nonplused and Back to Basics.

OBJECTIVES: The purpose of this article is to summarize the results of major randomized controlled trials (RCTs) comparing clinical outcomes of critically ill patients treated with normal saline (NS) or balanced salt solutions (BSSs), address discordant results of these studies, and provide direction for future investigations. DATA SOURCES: PubMed (2011 to January 2022) with bibliographies of retrieved articles searched for additional articles. STUDY SELECTION AND DATA EXTRACTION: RCTs comparing NS and BSSs in critically ill adult patients. DATA SYNTHESIS: Recently published large RCTs comparing NS with BSSs in heterogeneous populations of intensive care unit patients did not find significant differences in mortality, despite positive findings in some end points in prior RCTs. However, there were a number of methodologic issues common to the RCTs including: varying study designs and end points, clinician discretion for the majority or all treatments other than the primary intervention fluid, heterogeneous patients with varying levels of acuity, and lack of power to investigate potential subgroup differences. In addition, there were problematic issues related to blinding and use of nonstudy fluids. RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE: Intravenous fluids are a mainstay of supportive care for critically ill patients. Similar to the so-called crystalloid-colloid debate, there has been a long-standing debate among critical care clinicians and researchers concerning the preferred crystalloid solution, NS versus one of the available BSSs. CONCLUSIONS: Despite the recent publication of large multicenter RCTs, the preferred resuscitation fluid, NS or a BSS, for critically ill patients is still open for debate, although the available investigations do provide some direction for clinicians and for future investigations.

Mid-regional plasma pro-atrial natriuretic peptide and stroke volume responsiveness for detecting deviations in central blood volume following major abdominal surgery.

BACKGROUND: A reduced central blood volume is reflected by a decrease in mid-regional plasma pro-atrial natriuretic peptide (MR-proANP), a stable precursor of ANP, and a volume deficit may also be assessed by the stroke volume (SV) response to head-down tilt (HDT). We determined plasma MR-proANP during major abdominal procedures and evaluated whether the patients were volume responsive by the end of the surgery, taking the fluid balance and the crystalloid/colloid ratio into account. METHODS: Patients undergoing pancreatic (n = 25), liver (n = 25), or gastroesophageal (n = 38) surgery were included prospectively. Plasma MR-proANP was determined before and after surgery, and the fluid response was assessed by the SV response to 10° HDT after the procedure. The fluid strategy was based mainly on lactated Ringer's solution for gastroesophageal procedures, while for pancreas and liver surgery, more human albumin 5% was administered. RESULTS: Plasma MR-proANP decreased for patients undergoing gastroesophageal surgery (-9% [95% CI -3.2 to -15.3], p = .004) and 10 patients were fluid responsive by the end of surgery (∆SV > 10% during HDT) with an administered crystalloid/colloid ratio of 3.3 (fluid balance +1389 ± 452 ml). Furthermore, plasma MR-proANP and fluid balance were correlated (r = .352 [95% CI 0.031-0.674], p < .001). In contrast, plasma MR-proANP did not change significantly during pancreatic and liver surgery during which the crystalloid/colloid ratio was 1.0 (fluid balance +385 ± 478 ml) and 1.9 (fluid balance +513 ± 381 ml), respectively. For these patients, there was no correlation between plasma MR-proANP and fluid balance, and no patient was fluid responsive. CONCLUSION: Plasma MR-proANP was reduced in fluid responsive patients by the end of surgery for the patients for whom the fluid strategy was based on more lactated Ringer's solution than human albumin 5%.

Impact of the utilization of 500 mL IV bags on crystalloid resuscitation volumes administered to trauma patients.

INTRODUCTION: Administering large volumes of crystalloids to trauma patients has been shown to exacerbate metabolic complications of hemorrhage including dilutional coagulopathy and worsening acidosis The aim of this study was to evaluate crystalloid administration volumes in trauma patients after replacing 1 L IV containers with 500 mL IV containers in the emergency department trauma resuscitation bay. MATERIALS AND METHODS: This was a single-center, IRB-approved, retrospective cohort evaluation of adult trauma patients conducted at an 864-bed community tertiary referral center located in the southeastern United States. Patterns of crystalloid administration were examined before and after the trauma resuscitation bay began to exclusively stock 500 mL IV containers. The primary outcome was mean total crystalloid volume infused from time of injury to hospital admission. Secondary outcomes included mean total crystalloid volume infused prior to administration of blood products, proportion of patients who received less than 2 L total of crystalloids, time to initiation of blood products, and mortality in both the emergency department and in-hospital. RESULTS: Patient characteristics were largely similar between both groups including age, mechanism of injury, and Injury Severity Score. For the primary outcome, the mean total crystalloid volume infused from time of injury to hospital administration, patients in the 500 mL IV fluid container group were administered 555 mL less crystalloid when compared to the 1 L IV fluid container group, 1048 mL vs 1603 mL (p < 0.01; 95% CI 406 mL - 704 mL), respectively. After conversion to the 500 mL IV container bags, there was a 27.5% increase in the proportion of patients receiving less than 2 L of crystalloid, 90.5% vs 63.0% in the 500 mL IV fluid container and 1 L IV fluid container groups, respectively (p < 0.01). CONCLUSIONS: Due to reduced mortality, expanding literature and guidelines clearly support minimizing IV crystalloid resuscitation. Institutions must now work to minimize use of IV crystalloids to hemorrhaging trauma patients and a simple solution of using smaller IV fluid bags was shown to improve adherence to this practice.

Reliability of Marked Scales on Intravenous Fluid Plastic Bags.

Precise fluid administration is important to prevent hypo- or hypervolemia. However, the accuracy of scales marked on intravenous (IV) fluid plastic bags had remained unknown. Ten 1 L sized IV crystalloids were prepared from each of three manufacturers (H, J, and D). At each scale, the actual volume of the IV fluid was measured. Differences with the measured volumes for each scale were investigated between the three manufacturers. All initial total volume was greater than 1 L. Except for the full-filled level, H overfilled, whereas J and D filled less. For J and D, the maximal differences between the scale and the measured volume were about 200 mL. Fluid volumes of each scale were significantly different among the three manufacturers (P < 0.001). It is inaccurate to measure the amount of fluid depending on the IV bag scales. Clinicians must use electronic infusion pumps for accurate fluid administration.

Albumin in adult cardiac surgery: a narrative review.

PURPOSE: Intravascular fluids are a necessary and universal component of cardiac surgical patient care. Both crystalloids and colloids are used to maintain or restore circulating plasma volume and ensure adequate organ perfusion. In Canada, human albumin solution (5% or 25% concentration) is a colloid commonly used for this purpose. In this narrative review, we discuss albumin supply in Canada, explore the perceived advantages of albumin, and describe the clinical literature supporting and refuting albumin use over other fluids in the adult cardiac surgical population. SOURCE: We conducted a targeted search of PubMed, Embase, Medline, Web of Science, ProQuest Dissertations and Theses Global, the Cochrane Central Register of Controlled trials, and the Cochrane Database of Systematic Reviews. Search terms included albumin, colloid, cardiac surgery, bleeding, hemorrhage, transfusion, and cardiopulmonary bypass. PRINCIPAL FINDINGS: Albumin is produced from fractionated human plasma and imported into Canada from international suppliers at a cost of approximately $21 million CAD per annum. While it is widely used in cardiac surgical patients across the country, it is approximately 30-times more expensive than equivalent doses of balanced crystalloid solutions, with wide inter-institutional variability in use and no clear association with improved outcomes. There is a general lack of high-quality evidence for the superiority of albumin over crystalloids in this patient population, and conflicting evidence regarding safety. CONCLUSIONS: In cardiac surgical patients, albumin is widely utilized despite a lack of high- quality evidence supporting its efficacy or safety. A well-designed randomized controlled trial is needed to clarify the role of albumin in cardiac surgical patients.

RéSUMé: OBJECTIF: Les liquides intravasculaires sont une composante nécessaire et universelle des soins aux patients de chirurgie cardiaque. Les cristalloïdes et les colloïdes sont utilisés pour maintenir ou restaurer le volume plasmatique en circulation et assurer une perfusion adéquate des organes. Au Canada, les solutions d'albumine humaine (concentration de 5 % ou 25 %) constituent un colloïde couramment utilisé à cette fin. Dans ce compte rendu narratif, nous discutons de l'approvisionnement en albumine au Canada, explorons les avantages perçus de l'albumine et décrivons la littérature clinique soutenant ou réfutant l'utilisation de l'albumine par rapport à d'autres solutions pour la population chirurgicale cardiaque adulte. SOURCES: Nous avons effectué une recherche ciblée dans les bases de données PubMed, Embase, Medline, Web of Science, ProQuest Dissertations and Theses Global, le Cochrane Central Register of Controlled trials et la Cochrane Database of Systematic Reviews. Les termes de recherche (en anglais) incluaient albumine, colloid, cardiac surgery, bleeding, hemorrhage, transfusion, et cardiopulmonary bypass (soit albumine, colloïde, chirurgie cardiaque, saignement, hémorragie, transfusion et circulation extracorporelle). CONSTATATIONS PRINCIPALES: L'albumine est fabriquée à partir de plasma humain fractionné et importée au Canada à partir de fournisseurs internationaux au coût d'environ 21 millions CAD par année. Bien qu'elle soit largement utilisée chez les patients de chirurgie cardiaque à travers le pays, elle est environ 30 fois plus coûteuse que des doses équivalentes de solutions cristalloïdes équilibrées, avec une grande variabilité interinstitutionnelle quant à son utilisation et aucune association claire avec des devenirs améliorés. Il n'existe en général pas de données probantes de qualité élevée confirmant la supériorité de l'albumine par rapport aux cristalloïdes dans cette population de patients, et les données probantes quant à son innocuité sont contradictoires. CONCLUSION: Chez les patients de chirurgie cardiaque, l'albumine est largement utilisée en dépit d'un manque de données probantes de haute qualité soutenant son efficacité ou son innocuité. Une étude randomisée contrôlée bien conçue est nécessaire pour clarifier le rôle de l'albumine chez les patients de chirurgie cardiaque.

Comparison of Commercially Available Balanced Salt Solution and Ringer's Lactate on Extent of Correction of Metabolic Acidosis in Critically Ill Patients.

INTRODUCTION: Appropriate early fluid resuscitation is ubiquitous for critically ill patients with metabolic acidosis. Owing to harmful effects of normal saline, commercially prepared balanced salt solutions are being used. However, there is no study comparing use of Ringer's lactate (RL) and commercially available balanced salt solutions in critically ill patients. MATERIALS AND METHODS: A randomized controlled trial was conducted during July 2016 to December 2017. Fifty adult patients admitted to intensive care unit with metabolic acidosis were randomized into group RL or group acetate solution (AC). Respective trial fluid was administered at 20 mL/kg/hour for first hour and 10 mL/kg/hour for second hour. Arterial blood gas analysis samples were taken 15 minutes apart. The fluid resuscitation was continued till pH got corrected to 7.3 or 2 hours, whichever was earlier. The primary aim was to compare time to correct metabolic acidosis in both the groups. The secondary outcomes were the extent of correction of metabolic acidosis, total volume of fluid used, and total cost per patient. RESULTS: Demographic parameters, APACHE II score, and baseline investigations were comparable. The metabolic acidosis got corrected in 12 patients in group AC and 10 patients in group RL (p value = 0.66). The mean time for correction of metabolic acidosis was 57 ± 3.85 minutes in group RL and 56.25 ± 4.22 minutes in group AC (p value =0.95). The extent of correction of metabolic acidosis and total volume of fluid used was also comparable (p value = 0.05). However, the cost of fluid used was significantly higher in group AC (p value < 0.01). CONCLUSION: During administration of balanced salt solutions, RL or AC, in critically ill patients with metabolic acidosis, AC did not confer any advantage in time to or extent of correction of metabolic acidosis. CLINICAL SIGNIFICANCE: There is no difference in acid-base status with use of different types of balanced salt solutions for resuscitation in critically ill patients. HOW TO CITE THIS ARTICLE: Rawat N, Sahni N, Yaddanapudi L. Comparison of Commercially Available Balanced Salt Solution and Ringer's Lactate on Extent of Correction of Metabolic Acidosis in Critically Ill Patients. Indian J Crit Care Med 2020;24(7):539-543.

Sickle red blood cells are more susceptible to in vitro haemolysis when exposed to normal saline versus Plasma-Lyte A.

BACKGROUND: Normal saline has been the fluid of choice for resuscitation, rehydration and fluid replacement during plasma or red cell exchange/cytapheresis. There are increased concerns about its clinical effects and data showing it causes more haemolysis in vitro than buffered solutions such as Plasma-Lyte A. METHODS: We investigated whether normal saline or Plasma-Lyte A was associated with greater haemolysis during hours of in vitro incubation with both normal red cells and samples from patients with sickle cell anaemia. RESULTS: Sickle red cells haemolysed more than normal red cells did in both crystalloid solutions. The results of 24-hour exposure to saline were particularly striking (median of 163 mg/dl (IQ range 105-247) for sickle red cells vs. 53 (48-92) for normal red cells (P < 0·0001). In patient samples containing variable quantities of haemoglobin S red cells, increased haemoglobin S was associated with increased haemolysis. This effect was greater for normal saline than Plasma-Lyte A (P = 0·12). CONCLUSIONS: These in vitro models demonstrate that short-term ex vivo exposure of sickle red cells to normal saline leads to greater haemolysis than short-term exposure of normal red cells, and this effect is exacerbated by normal saline. Whether use of normal saline causes increased haemolysis in vivo is unknown. Given recent evidence that normal saline increases renal failure and mortality in critically ill patients, further studies are urgently needed.

Fluid management in patients undergoing cardiac surgery: effects of an acetate- versus lactate-buffered balanced infusion solution on hemodynamic stability (HEMACETAT).

BACKGROUND: Recent evidence suggests that acetate-buffered infusions result in better hemodynamic stabilization than 0.9% saline in patients undergoing major surgery. The choice of buffer in balanced crystalloid solutions may modify their hemodynamic effects. We therefore compared the inopressor requirements of Ringer's acetate and lactate for perioperative fluid management in patients undergoing cardiac surgery. METHODS: Using a randomized controlled double-blind design, we compared Ringer's acetate (RA) to Ringer's lactate (RL) with respect to the average rate of inopressor administered until postoperative hemodynamic stabilization was achieved. Secondary outcomes were the cumulative dose of inopressors, the duration of inopressor administration, the total fluid volume administered, and the changes in acid-base homeostasis. Patients undergoing elective valvular cardiac surgery were included. Patients with severe cardiac, renal, or liver disease were excluded from the study. RESULTS: Seventy-five patients were randomly allocated to the RA arm, 73 to the RL. The hemodynamic profiles were comparable between the groups. The groups did not differ with respect to the average rate of inopressors (RA 2.1 mcg/kg/h, IQR 0.5-8.1 vs. RL 1.7 mcg/kg/h, IQR 0.7-8.2, p = 0.989). Cumulative doses of inopressors and time on individual and combined inopressors did not differ between the groups. No differences were found in acid-base parameters and their evolution over time. CONCLUSION: In this study, hemodynamic profiles of patients receiving Ringer's lactate and Ringer's acetate were comparable, and the evolution of acid-base parameters was similar. These study findings should be evaluated in larger, multi-center studies. TRIAL REGISTRATION: Clinicaltrials.gov NCT02895659 . Registered 16 September 2016.

Volume kinetics of Ringer's lactate solution in acute inflammatory disease.

BACKGROUND: Little is known about the turnover of crystalloid fluids infused in patients with acute systemic inflammation. We hypothesised that systemic inflammation would be associated with altered distribution and elimination of Ringer's lactate solution (volume kinetics). METHODS: Ringer's lactate solution (15 ml kg-1) was infused intravenously over 35 min in patients undergoing cholecystectomy (n=20) or appendectomy (n=20) starting before induction of general anaesthesia. Blood samples and urine were collected over the following 2 h. Plasma concentrations of inflammatory (tumour necrosis factor-α, interleukin-10, and C-reactive protein) and endothelial damage (syndecan-1) biomarkers were quantified by enzyme-linked immunosorbent assay. The volume kinetics was studied using mixed-effect modelling. RESULTS: Ongoing surgery (duration: 30-45 min) increased the rate constant for fluid transfer from the plasma to the extravascular space (k12; from 32 to 57×10-3 min-1; P<0.001), and decreased the elimination rate constant (k10; from 5.3 to 0.6×10-3 min-1; P<0.001). A lower mean arterial pressure was associated with reduced elimination, independent of conscious/anaesthetised state. The redistribution of fluid back to the plasma occurred more slowly in the group with appendicitis (P<0.02), in whom higher plasma concentrations of C-reactive protein were measured [median: 38.1 (range 1.8-143.6) vs 1.3 (0.1-159.0) µg ml-1; P<0.001]. However, no biomarkers for inflammation or endothelial damage were significantly associated covariates in the kinetic model. CONCLUSIONS: No association was found between the volume kinetics of Ringer's lactate solution and the degree of inflammation as indicated by established biomarkers in patients with cholecystitis or appendicitis. However, the rate of elimination was greatly retarded by general anaesthesia in both groups. CLINICAL TRIAL REGISTRATION: ChiCTR-IOR-15006063.

Impact of resuscitation fluid bag size availability on volume of fluid administration in the intensive care unit.

BACKGROUND: Iatrogenic fluid overload is associated with increased mortality in the intensive care unit (ICU). Decisions on fluid therapy may, at times, be based on other factors than physiological endpoints. We hypothesized that because of psychological factors volume of available fluid bags would affect the amount of resuscitation fluid administered to ICU patients. METHODS: We performed a prospective intervention cross-over study at 3 Swedish ICUs by replacing the standard resuscitation fluid bag of Ringer's Acetate 1000 mL with 500 mL bags (intervention group) for 5 separate months and then compared it with the standard bag size for 5 months (control group). Primary endpoint was the amount of Ringer's Acetate per patient during ICU stay. Secondary endpoints were differences between the groups in cumulative fluid balance and change in body weight, hemoglobin and creatinine levels, urine output, acute kidney failure (measured as the need for renal replacement therapy, RRT) and 90-day mortality. RESULTS: Six hundred and thirty-five ICU patients were included (291 in the intervention group, 344 in the control group). There was no difference in the amount of resuscitation fluid per patient during the ICU stay (2200 mL [1000-4500 median IQR] vs 2245 mL [1000-5630 median IQR]), RRT rate (11 vs 9%), 90-day mortality (11 vs 10%) or total fluid balance between the groups. The daily amount of Ringer's acetate administered per day was lower in the intervention group (1040 (280-2000) vs 1520 (460-3000) mL; P = .03). CONCLUSIONS: The amount of resuscitation fluid administered to ICU patients was not affected by the size of the available fluid bags. However, altering fluid bag size could have influenced fluid prescription behavior.

Are we close to the ideal intravenous fluid?

The approach to i.v. fluid therapy for hypovolaemia may significantly influence outcomes for patients who experience a systemic inflammatory response after sepsis, trauma, or major surgery. Currently, there is no single i.v. fluid agent that meets all the criteria for the ideal treatment for hypovolaemia. The physician must choose the best available agent(s) for each patient, and then decide when and how much to administer. Findings from large randomized trials suggest that some colloid-based fluids, particularly starch-based colloids, may be harmful in some situations, but it is unclear whether they should be withdrawn from use completely. Meanwhile, crystalloid fluids, such as saline 0.9% and Ringer's lactate, are more frequently used, but debate continues over which preparation is preferable. Perhaps most importantly, it remains unclear how to select the optimal dose of fluid in different patients and different clinical scenarios. There is good reason to believe that both inadequate and excessive i.v. fluid administration may lead to poor outcomes, including increased risk of infection and organ dysfunction, for hypovolaemic patients. In this review, we summarize the current knowledge on this topic and identify some key pitfalls and some areas of agreed best practice.

Effects of intraoperative and early postoperative normal saline or Plasma-Lyte 148® on hyperkalaemia in deceased donor renal transplantation: a double-blind randomized trial.

BACKGROUND: Administration of saline in renal transplantation is associated with hyperchloraemic metabolic acidosis, but the effect of normal saline (NS) on the risk of hyperkalaemia or postoperative graft function is uncertain. METHODS: We compared NS with Plasma-Lyte 148® (PL) given during surgery and for 48 h after surgery in patients undergoing deceased donor renal transplantation. The primary outcome was hyperkalaemia within 48 h after surgery. Secondary outcomes were need for hyperkalaemia treatment, change in acid-base status, and graft function. RESULTS: Twenty-five subjects were randomized to NS and 24 to PL. The incidence of hyperkalaemia in the first 48 h after surgery was higher in the NS group; 20 patients (80%) vs 12 patients (50%) in the PL group (risk difference: 0.3; 95% confidence interval: 0.05, 0.55; P=0.037). The mean (sd) peak serum potassium was NS 6.1 (0.8) compared with PL 5.4 (0.9) mmol litre-1 (P=0.009). Sixteen participants (64%) in the NS group required treatment for hyperkalaemia compared with five (21%) in the PL group (P=0.004). Participants receiving NS were more acidaemic [pH 7.32 (0.06) vs 7.39 (0.05), P=0.001] and had higher serum chloride concentrations (107 vs 101 mmol litre-1, P<0.001) at the end of surgery. No differences in the rate of delayed graft function were observed. Subjects receiving PL who did not require dialysis had a greater reduction in creatinine on day 2 (P=0.04). CONCLUSIONS: Compared with PL, participants receiving NS had a greater incidence of hyperkalaemia and hyperchloraemia and were more acidaemic. These biochemical differences were not associated with adverse clinical outcomes. CLINICAL TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry: ACTRN12612000023853.

Effects of intraoperative liberal fluid therapy on postoperative nausea and vomiting in children-A randomized controlled trial.

BACKGROUND: Postoperative nausea and vomiting (PONV) is one of the most distressing complications following surgery. Supplemental perioperative fluid therapy might be an effective strategy to reduce PONV in children. OBJECTIVES: The study was conducted to evaluate the effects of intraoperative liberal fluid therapy with crystalloids on PONV in children. METHODS: In this randomized trial, a total of 150 children of 3-7 years undergoing lower abdominal and penile surgery under general anesthesia were randomly assigned into two groups. "Restricted group" received 10 mL kg-1 h-1 and "Liberal group" received 30 mL kg-1 h-1 infusion of Ringer's lactate solution intraoperatively. All patients received a caudal block and intravenous paracetamol for analgesia. No opioids and muscle relaxants were used. All episodes of nausea-vomiting and the requirement of rescue antiemetic were assessed during 24 hours postoperatively. RESULTS: The incidence of PONV was significantly less in the liberal group patients as compared to the restricted group; 33 (45.8%) patients in the restricted group had vomiting as compared to 20 (27.4%) patients in the liberal group (RR 0.59, 95% CI: 0.38-0.93, P=.021). The adjusted odds ratio of PONV for the liberal group vs restricted group was 2.24 (95% CI: 1.12-4.48, P=.022). The incidence of fluid intake during the first 6 postoperative hours was significantly higher in the restricted group patients; 60 (83%) children in the restricted group complained of thirst as compared to 12 (17%) children in the liberal group (RR 0.19, 95% CI: 0.18-0.33, P=.0001). The parents of the liberal group were more satisfied as compared to the restricted group (mean difference -0.9, 95% CI: -1.8, -0.1, P=.04). None of the children had any complication attributed to the liberal fluid therapy. CONCLUSION: Liberal intraoperative fluid therapy was found to be effective in reducing PONV in children undergoing lower abdominal surgery.

Safety of gelatin solutions for the priming of cardiopulmonary bypass in cardiac surgery: a systematic review and meta-analysis.

This systematic review and meta-analysis was conducted to evaluate the safety of gelatin versus hydroxyethyl starches (HES) and crystalloids when used for cardiopulmonary bypass (CPB)-priming in cardiac surgery. MEDLINE (Pubmed), Embase and CENTRAL were searched. We included only randomized, controlled trials comparing CPB-priming with gelatin with either crystalloids or HES-solutions of the newest generation. The primary endpoint was the blood loss during the first 24 hours. Secondary outcomes included perioperative transfusion requirements, postoperative kidney function, postoperative ventilation times and length of stay on the intensive care unit. Sixteen studies were identified, of which only ten met the inclusion criteria, representing a total of 824 adult patients: 4 studies compared gelatin with crystalloid, and 6 studies gelatin with HES priming. Only 2 of the studies comparing HES and gelatin reported postoperative blood loss after 24 hours. No significant difference in postoperative blood loss was found when results of both studies were pooled (SMD -0.12; 95% CI: -0.49, 0.25; P=0.52). Likewise, the pooled results of 3 studies comparing gelatin and crystalloids as a priming solution could not demonstrate significant differences in postoperative bleeding after 24 hours (SMD -0.07; 95% CI: -0.40, 0.26; P=0.68). No differences regarding any of the secondary outcomes could be identified. This systematic review suggests gelatins to have a safety profile which is non-inferior to modern-generation tetrastarches or crystalloids. However, the grade of evidence is rated low owing to the poor methodological quality of the included studies, due to inconsistent outcome reporting and lack of uniform endpoint definitions.

Fluid resuscitation management in patients with burns: update.

Since 1968, when Baxter and Shires developed the Parkland formula, little progress has been made in the field of fluid therapy for burn resuscitation, despite advances in haemodynamic monitoring, establishment of the 'goal-directed therapy' concept, and the development of new colloid and crystalloid solutions. Burn patients receive a larger amount of fluids in the first hours than any other trauma patients. Initial resuscitation is based on crystalloids because of the increased capillary permeability occurring during the first 24 h. After that time, some colloids, but not all, are accepted. Since the emergence of the Pharmacovigilance Risk Assessment Committee alert from the European Medicines Agency concerning hydroxyethyl starches, solutions containing this component are not recommended for burns. But the question is: what do we really know about fluid resuscitation in burns? To provide an answer, we carried out a non-systematic review to clarify how to quantify the amount of fluids needed, what the current evidence says about the available solutions, and which solution is the most appropriate for burn patients based on the available knowledge.

Isotonic crystalloid solutions: a structured review of the literature.

BACKGROUND: Several different crystalloid solutions are available for i.v. fluid administration but there is little information about their specific advantages and disadvantages. METHODS: We performed a systematic search of MEDLINE, EMBASE, and CENTRAL up until May 17, 2012, selecting all prospective human studies that directly compared any near-isotonic crystalloids and reported any outcome. RESULTS: From the 5060 articles retrieved in the search, only 28 met the selection criteria. There was considerable heterogeneity among the studies. Several articles reported an increased incidence of hyperchloraemic acidosis with the use of normal saline, and others an increase in blood lactate levels when large amounts of Ringer's lactate solutions were infused. From the limited data available, normal saline administration appears to be associated with increased blood loss and greater red blood cell transfusion volumes in high-risk populations compared to Ringer's lactate. Possible effects of the different solutions on renal function, inflammatory response, temperature, hepatic function, glucose metabolism, and splanchnic perfusion are also reported. The haemodynamic profiles of all the solutions were similar. CONCLUSIONS: Different solutions have different effects on acid-base status, electrolyte levels, coagulation, renal, and hepatic function. Whether these differences have clinical consequences remains unclear.

Impact of intraoperative fluid administration on outcome in patients undergoing robotic-assisted laparoscopic prostatectomy--a retrospective analysis.

BACKGROUND: Robotic-assisted laparoscopic prostatectomy (RALP) gained much popularity during the last decade. Although the influence of intraoperative fluid management on patients' outcome has been largely discussed in general, its impact on perioperative complications and length of hospitalization in patients undergoing RALP has not been examined so far. We hypothesized that a more restrictive fluid management might lead to a shortened length of hospitalization and a decreased rate of complications in our patients. METHODS: Retrospective analysis of data of 182 patients undergoing RALP at an University Hospital (first series of RALP performed at the center). RESULTS: The amount of fluid administered was initially normalized for body mass index of the patient and the duration of the operation and additionally corrected for age and the interaction of these variables. The application of crystalloids (multiple linear regression model, estimate = -0.044, p = 0.734) had no effect on the length of hospitalization, whereas a negative effect was found for colloids (estimate = -8.317, p = 0.021). Additionally, a significant interaction term between age and the amount of colloid applied (estimate = 0.129, p = 0.028) was calculated. Evaluation of the influence of intraoperative fluid administration using multiple logistic regression models corrected for body mass index, duration of the surgery and additionally for age revealed a negative effect of crystalloids on the incidence of an anastomotic leak between bladder and urethra (estimate = -23.860, p = 0.017), with a significant interaction term between age and the amount of crystalloids (estimate = 0.396, p = 0.0134). Colloids had no significant effect on this particular complication (estimate = 1.887, p = 0.524). Intraoperative blood loss did not alter the incidence of an anastomotic leak (estimate = 0.001, p = 0.086), nor did it affect the length of hospitalization (estimate = 0.0001, p = 0.351). CONCLUSIONS: In accordance to the findings of our study, we suggest that a standardized, more restrictive fluid management might be beneficial in patients undergoing RALP. In older patients this measure would be able to shorten the length of hospitalization and to decrease the incidence of anastomosis leakage as a major complication.