Intravenous volume replacement: which fluid and why?

Pediatric perioperative fluid management

The purpose of perioperative fluid management in children is to maintain adequate volume status, electrolyte level, and endocrine system homeostasis during the perioperative period. Although hypotonic solutions containing glucose have traditionally been used as pediatric maintenance fluids, recent studies have shown that isotonic balanced crystalloid solutions lower the risk of hyponatremia and metabolic acidosis perioperatively. Isotonic balanced solutions have been found to exhibit safer and more physiologically appropriate characteristics for perioperative fluid maintenance and replacement. Additionally, adding 1-2.5% glucose to the maintenance fluid can help prevent children from developing hypoglycemia as well as lipid mobilization, ketosis, and hyperglycemia. The fasting time should be as short as possible without compromising safety; recent guidelines have recommended that the duration of clear fluid fasting be reduced to 1 h. The ongoing loss of fluid and blood as well as the free water retention induced by antidiuretic hormone secretion are unique characteristics of postoperative fluid management that must be considered. Reducing the infusion rate of the isotonic balanced solution may be necessary to avoid dilutional hyponatremia during the postoperative period. In summary, perioperative fluid management in pediatric patients requires careful attention because of the limited reserve capacity in this population. Isotonic balanced solutions appear to be the safest and most beneficial choice for most pediatric patients, considering their physiology and safety concerns.

Effects of rapid fluid infusion on hemoglobin concentration: a systematic review and meta-analysis

Background

Rapid fluid administration may decrease hemoglobin concentration (Hb) by a diluting effect, which could limit the increase in oxygen delivery (DO₂) expected with a positive response to fluid challenge in critically ill patients. Our aim was to quantify the decrease in Hb after rapid fluid administration.

Methods

Our protocol was registered in PROSPERO (CRD42020165146). We searched PubMed, the Cochrane Database, and Embase from inception until February 15, 2022. We selected studies that reported Hb before and after rapid fluid administration (bolus fluid given over less than 120 min) with crystalloids and/or colloids in adults. Exclusion criteria were studies that included bleeding patients, or used transfusions or extracorporeal circulation procedures. Studies were divided according to whether they involved non-acutely ill or acutely ill (surgical/trauma, sepsis, circulatory shock or severe hypovolemia, and mixed conditions) subjects. The mean Hb difference and, where reported, the DO₂ difference before and after fluid administration were extracted. Meta-analyses were conducted to assess differences in Hb before and after rapid fluid administration in all subjects and across subgroups. Random-effect models, meta-regressions and subgroup analyses were performed for meta-analyses. Risk of bias was assessed using the Cochrane Risk of Bias Assessment Tool. Inconsistency among trial results was assessed using the I² statistic.

Results

Sixty-five studies met our inclusion criteria (40 in non-acutely ill and 25 in acutely ill subjects), with a total of 2794 participants. Risk of bias was assessed as “low” for randomized controlled trials (RCTs) and ‘low to moderate’ for non-RCTs. Across 63 studies suitable for meta-analysis, the Hb decreased significantly by a mean of 1.33 g/dL [95% CI − 1.45 to − 1.12; p < 0.001; I² = 96.88] after fluid administration: in non-acutely ill subjects, the mean decrease was 1.56 g/dL [95% CI − 1.69 to − 1.42; p < 0.001; I² = 96.71] and in acutely ill patients 0.84 g/dL [95% CI − 1.03 to − 0.64; p = 0.033; I² = 92.91]. The decrease in Hb was less marked in patients with sepsis than in other acutely ill patients. The DO₂ decreased significantly in fluid non-responders with a significant decrease in Hb.

Conclusions

Hb decreased consistently after rapid fluid administration with moderate certainty of evidence. This effect may limit the positive effects of fluid challenges on DO₂ and thus on tissue oxygenation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-022-04191-x.

Modified fluid gelatin 4% for perioperative volume replacement in pediatric patients (GPS): Results of a European prospective noninterventional multicenter study

INTRODUCTION

Modified fluid gelatin 4% is approved for use in children, but there is still a surprising lack of clinical studies including large numbers of pediatric patients. Therefore, we performed a European prospective noninterventional multicenter study to evaluate the use of a modified fluid gelatin 4% in saline (sal-GEL) or an acetate-containing balanced electrolyte solution (bal-GEL) in children undergoing major pediatric surgery.

AIMS

The primary aim was to assess the indications and dosing of modified fluid gelatin, and the secondary aim was to assess the safety and efficacy, focusing, in particular, on routinely collected clinical parameters.

METHODS

Children aged up to 12 years with ASA risk scores of I-III receiving sal-GEL or bal-GEL were followed perioperatively. Demographic data, surgical procedures performed, anesthesia, hemodynamic and laboratory data, adverse events, and adverse drug reactions were documented using a standardized case report form.

RESULTS

601 children that were investigated at 13 European pediatric centers from May 2015 to March 2020 (sal-GEL 20.1%, bal-GEL 79.9%; mean age 29.1 ± 38.6 (range 0-144) months; body weight 12.1 ± 10.5 (1.4-70) kg) were included in the analysis. The most frequent indications for GEL infusion were hemodynamic instability without bleeding (76.0%), crystalloids alone not being sufficient for hemodynamic stabilization (55.7%), replacement of preoperative deficit (26.0%), and significant bleeding (13.0%). Mean infused GEL volume was 13.0 ± 5.3 (2.4-37.5) ml kg^-1 . The total dose was affected by age, with higher doses in younger patients. After gelatin infusion, mean arterial pressure increased (mean change 8.5 ± 7.3 [95% CI: 8 to 9.1] mmHg), and the hemoglobin concentrations decreased significantly (mean change -1.1 ± 1.8 [95% CI: -1.2 to -0.9] g·dL^-1 ). Acid-base parameters were more stable with bal-GEL. No serious adverse drug reactions directly related to gelatin (i.e., anaphylactoid reaction, clotting disorders, and renal failure) were observed.

CONCLUSION

Moderate doses up to 20 ml kg^-1 of modified fluid gelatin were infused most frequently to improve hemodynamic stability in children undergoing major pediatric surgery. The acid-base balance was more stable when gelatin in a balanced electrolyte solution was used instead of saline. No serious adverse drug reactions associated with gelatin were observed.

Perioperative fluid management in children: can we sum it all up now?

PURPOSE OF REVIEW

The composition and type of intravenous fluids during paediatric anaesthesia have been subjects of debates for decades. Errors in perioperative fluid management in children may lead to serious complications and a negative outcome. Therefore, in this review, historical and recent developments and recommendations for perioperative fluid management in children are presented, based on physiology and focused on safety and efficacy.

RECENT FINDINGS

Optimized fasting times and liberal clear fluid intake until 1 h improve patient comfort and metabolic and haemodynamic condition after induction of anaesthesia. Physiologically composed balanced isotonic electrolyte solutions are safer than hypotonic electrolyte solutions or saline 0.9% to protect young children against the risks of hyponatraemia and hyperchloraemic acidosis. For intraoperative maintenance infusion, addition of 1-2% glucose is sufficient to avoid hypoglycaemia, lipolysis or hyperglycaemia. Modified fluid gelatine or hydroxyethyl starch in balanced electrolyte solution can safely be used to quickly normalize blood volume in case of perioperative circulatory instability and blood loss.

SUMMARY

Physiologically composed balanced isotonic electrolyte solutions are beneficial for maintaining homeostasis, shifting the status more towards the normal range in patients with preexisting imbalances and have a wide margin of safety in case of accidental hyperinfusion.

Hazardous Medications in Children with Egg, Red Meat, Gelatin, Fish, and Cow's Milk Allergy

Childhood food allergies are a growing public health problem. Once the offending food allergens have been identified, a strict elimination diet is necessary in treatment or prevention of most of the allergic reactions. Accidental food ingestion can lead to severe anaphylaxis. Food- derived substances can be used in medications at various stages of the manufacturing process. In this review, the possible roles of medications which may contain egg, red meat, gelatin, and fish allergens on allergic reactions in children with food allergy were evaluated.

Does Hemodilution Enhance or Compromise Blood Coagulation?

The reduction in oxygen-carrying capacity during hemodilution is well tolerated by most patients. However, hemodilution not only decreases O2 transport capacity, but also may influence blood coagulation. Advanced hemodilution with crystalloids does not compromise blood coagulation and, with moderate hemodilution, even augmented blood coagulation may develop. In contrast, blood coagulation is compromised during hemodilution with colloids. The effect of human serum albumin and gelatin is relatively modest, but significantly more than during equivalent hemodilution with crystalloids. Dextran and hydroxyethyl starch compromise blood coagulation more. This results from reduction of factor VIII, a decrease in plasmatic coagulation, and an impairment of platelet function. For hydroxyethyl starch, molecular size and degree of substitution are crucial for the effect on blood coagulation, with hydroxyethyl starch (200,000/0.5) having the least effect. Furthermore, accelerated fibrin formation is observed during hemodilution with Dextran, hydroxyethyl starch, and gelatin with an altered fibrin structure. In vitro clot lysis is also increased with all colloids, but there are no reports on augmented in vivo fibrin degradation products. Besides the effect on intraoperative blood coagulation, the hemodynamic effectiveness, duration thereof, effect on microcirculation and edema formation, and, in particular, the effect on the hypercoagulable state in the postoperative period need to be considered in the choice of the replacement fluid during hemodilution and intraoperative blood loss.

Blood pressure in the very low birth weight neonate

Few aspects of management of very low birth weight (VLBW; <1500 g) neonates have generated as much controversy as the assessment of blood pressure (BP) and need for treatment of perceived abnormalities of this physiologic variable. The approach to this problem may differ greatly among various institutions and even among clinicians within a given center. The purpose of this manuscript is to review available information regarding physiologic determinants and measurement of BP in VLBW neonates, normative data for BP, clinical factors that may affect BP in these at-risk neonates and studies in which presumed abnormalities of BP resulted in adverse clinical outcomes. Options for treatment of low BP in VLBW neonates also will be discussed.

Costs related to inappropriate use of albumin in Spain

BACKGROUND

Albumin has been used in various treatments for > 50 years, but, recently, its use in clinical practice has become very controversial.

OBJECTIVE

To assess the use of albumin in clinical practice in the public hospital setting in Andalucía, Spain, focusing on the economic repercussions of the inappropriate use of albumin.

METHODS

Multicentered observational study in 22 public hospitals in which all patients receiving albumin (from start to conclusion of treatment) were assessed during a five-month period on three predetermined, nonconsecutive days. The clinical indications for albumin were evaluated on the basis of Guidelines, a consensus document created by a multidisciplinary team for dissemination by the Governmental Health Authority to all hospitals within its purview. The data were abstracted from the patient case report forms by the pharmacist selected to compile the data in each of the participating hospitals.

RESULTS

A total of 242 forms reporting the use of 62,282 g of albumin were evaluated. The most frequent prescribing motives were nutritional intervention (23%), paracentesis in cirrhotic patients (19%), and radical surgery (11%). Only 59 prescriptions (24%), corresponding to 14,539 g of albumin (23%), were considered appropriate. The total cost of albumin therapy for the 242 cases was $183,796 (US$); $42,905 (23%) of this figure was the cost of appropriate use of albumin and $140,891 (77%) was the amount related to inappropriate use.

CONCLUSIONS

Evaluated against model guidelines, the use of most of the albumin, deemed clinically necessary by the prescribers, was considered unnecessary or inappropriate. Hence, institutions need to define and implement guidelines that focus on responsible use of such agents in an increasingly cost-conscious healthcare environment.

Haemodynamic, acid-base and electrolyte changes during plasma replacement with hydroxyethyl starch or crystalloid solution in young pigs

We investigated haemodynamic, acid-base and electrolyte changes during almost total plasma replacement with hydroxyethyl starch (HES) and physiological balanced electrolyte solution (PBE) by using a cell saver in ten young pigs. In the PBE group an additional 3550 (444) ml crystalloid solution [Mean (SD)] was infused over the course of the study in order to maintain pulmonary capillary wedge pressure. Plasma protein levels decreased in both groups and the colloid osmotic pressure increased in HES and decreased in PBE. At the end of the study, body weight [HES 10.4 (1), PBE 13.1 (1.4) kg, P < 0.01] and lactic acid concentration [HES 0.9 (0.3), PBE 2.9 (1. 3) mmol.l -1, P < 0.01] was higher and tissue oxygen delivery [HES 327 (22), PBE 89 (29) ml.min.m2, P < 0.01] was lower in the PBE group. There were only moderate acid-base changes in both groups, but at the end, anion gap was significant lower in HES. In conclusion, maintenance of colloid osmotic pressure close to the physiological range of infants seems to be advantageous during major paediatric surgery.

Haemoconcentration by gelatin-induced acceleration of erythrocyte sedimentation rate

Erythrocyte sedimentation rates from 40 suspensions of packed red blood cells in modified fluid gelatin, 4% albumin solution, 6% hydroxyethyl starch and normal saline were measured at room temperature using Westergren's method. The erythrocyte sedimentation rate was extremely high in gelatin and this increase was significant after 10-60 min when compared with the other fluids. Erythrocyte sedimentation rates in albumin, hydroxyethyl starch and normal saline were low and there were no differences between these fluids [erythrocyte sedimentation after 60 min, median (interquartile range): gelatin 128 (111.2-130.0) mm, albumin 2 (1.5-2.0) mm, hydroxyethyl starch 1.5 (1.0-1.6) mm, normal saline 2 (1.9-2.5) mm, p < 0.0001]. The addition of twice the volume of modified fluid gelatin to a volume of red blood cells leads to rapid acceleration of the erythrocyte sedimentation rate. This is caused by increased erythrocyte aggregation, and in clinical practice this effect may be useful for the haemoconcentration of diluted blood from cardiopulmonary bypass circuits or cell-saver autotransfusion in paediatric surgery.

Randomised controlled trial of colloid or crystalloid in hypotensive preterm infants

AIM

To compare the efficacy of a colloid (5% albumin) and a crystalloid (isotonic saline) solution for treating hypotension in mechanically ventilated preterm infants.

METHODS

Sixty three preterm infants weighing 540 to 1950 g at birth and with gestational ages of 23 to 34 weeks, who developed hypotension (mean arterial pressure < 25, 30, and 35 mm Hg for infants with birthweight < 1, 1-1.49, and 1.5-1.99 kg, respectively) within the first 2 hours of life, were randomly allocated to receive intravenous infusions at 10 ml/kg of either 5% albumin (group 1, n = 32) or isotonic (0.9%) saline (group 2, n = 31). Inotropic support with dopamine infusion was given if the infants remained hypotensive after a total of three infusions (30 ml/kg). Subsequent extra doses of volume expander in the form of 5% albumin was given, depending on the infant's blood pressure.

RESULTS

There was no difference in the volume of the test solutions required between the two groups. Outcome, as assessed by the number of infants requiring inotropic support and death or chronic lung disease, did not differ between the groups. After inotropic support, however, group 1 required significantly more volume expander to maintain normal blood pressure (median: 27.5 ml/kg vs 10 ml/kg; P = 0.0187) and had a higher mean (SEM) percentage weight gain within the first 48 hours of life (at 24 hours: 6.3(1.3)% vs 3.3(0.8)%; P = 0.049; at 48 hours: 5.9(1.9)% vs 0.9(1.7)%; P = 0.045). The difference in weight gain was significant at 48 hours even when only those infants not requiring inotropic support or extra 5% albumin were compared (group 1: 1.5(1.5)%, group 2: -4.2(1.1)%; P = 0.027).

CONCLUSIONS

Isotonic saline is as effective as 5% albumin for treating hypotension in preterm infants, and it has the additional advantage of causing less fluid retention in the first 48 hours.

A comparison of 4.5% human albumin solution and Haemaccel in neonates undergoing major surgery

In a randomized blinded study we compared two colloid solutions in 30 neonates undergoing major surgery. Fifteen neonates received 4.5% Human albumin solution (HAS) (mean volume 25.6 ml.kg-1, SD 9.5) and the others received Haemaccel (Hoechst) (24.9 ml.kg-1, SD 10). Pre and postoperative plasma albumin and haemoglobin concentrations and plasma colloid osmotic pressure (COP) were compared. In the group given Haemaccel there was an appreciable and statistically significant decrease in the mean plasma albumin concentration from 34.27 to 28.27 g.1(-1) (mean difference 6, CI 3.38 to 8.62) and the mean COP decreased significantly from 22.2 to 19.9 mmHg (mean difference 2.3, CI 0.3 to 4.5). In the HAS group there was no significant change in either the plasma albumin concentration or COP. There was a small but significant decrease in the mean haemoglobin concentration from 15.92 to 14.35 g.dl-1 (mean difference 1.56, CI 0.57 to 2.55) after HAS. We conclude that HAS is the superior colloid for volume replacement in neonates undergoing surgery.

Transfusion and surgery

In this survey of transfusion in surgery, we have attempted to provide the surgeon with an understanding of the problems associated with homologous transfusion and a practical knowledge of treatment strategies and alternatives designed to reduce homologous blood exposure. Such a review cannot be encyclopedic. Our hope is that it will serve the reader as a stimulus to examine his or her transfusion practices and as a guide for future self-learning.