Fluids and body composition during anesthesia in children and adolescents: A pilot study

The purpose of this study is to evaluate the intracellular and extracellular volume before and after anesthesia in order to ascertain their variations and determine the potential utility of this information in optimizing intraoperative fluid administration practices. A bioimpedance spectroscopy device (body composition monitor, BCM) was used to measure total body fluid volume, extracellular volume, and intracellular volume. BCM measurements were performed before and after general anesthesia in unselected healthy children and adolescents visiting the Pediatric Institute of Southern Switzerland for low-risk surgical procedures hydrated with an isotonic solution. In 100 children and adolescents aged 7.0 (4.8-11) years (median and interquartile range), the average total body water increased perioperatively with a delta value of 182 (0-383) mL/m2 from pre- to postoperatively, as well as the extracellular water content, which had a similar increase with a delta value of 169 (19-307) mL/m2. The changes in total body water and extracellular water content significantly correlated with the amount of fluids administered. The intracellular water content did not significantly change.   Conclusion: Intraoperative administration of isotonic solutions results in a significant fluid accumulation in low-risk schoolchildren during general anesthesia. The results suggest that children without major health problems undergoing short procedures do not need any perioperative intravenous fluid therapy, because they are allowed to take clear fluids up to 1 h prior anesthesia. In future studies, the use of BCM measurements has the potential to be valuable in guiding intraoperative fluid therapy. What is Known: • Most children who undergo common surgical interventions or investigations requiring anesthesia are nowadays hydrated at a rate of 1700 mL/m2/day with an isotonic solution. • The use bioimpedance spectroscopy for the assessment of fluid status in healthy children has already been successfully validated. • The bioimpedance spectroscopy is already currently widely used in various nephrological settings to calculate fluid overload and determine patient's optimal fluid status. What is New: • Routine intraoperative fluid administration results in a significant fluid accumulation during general anesthesia in low-risk surgical procedures. • This observation might be relevant for children and adolescents with conditions predisposing to fluid retention. • In future studies, the use of BCM measurements has the potential to be valuable in guiding intraoperative fluid therapy.

Comparison of bicarbonate Ringer's solution with lactated Ringer's solution among postoperative outcomes in patients with laparoscopic right hemihepatectomy: a single-centre randomised controlled trial

The study was aimed to investigate the positive impact of bicarbonate Ringer's solution on postoperative outcomes in patients who underwent laparoscopic right hemihepatectomy. Patients in the two groups were infused with lactated Ringer's solution (LRS, n = 38) and the bicarbonate Ringer's solution (BRS, n = 38) at a rate of 5 ml·kg-1·h-1. The stroke volume was monitored and 200 ml of hydroxyethyl starch with 130/0.4 sodium chloride injection (Hes) of a bolus was given in the first 5-10 min. The main outcome was to test lactic acid (LAC) concentration before and after surgery. The concentrations of LAC in the LRS group were higher than in the BRS group at 2 h after operation began, at the end of the operation and 2 h after the operation. Overall, the parameters including pH, base excess (BE), HCO3-, aspartate transaminase (AST) and alanine transaminase (ALT) were improved. The values of bilirubin in the LRS group were higher and albumin were lower than in the BRS group at post-operation 1st and 2nd day (P<0.05). The time of prothrombin time (PT) and activated partial thromboplastin time (APTT) in the LRS group were longer than that in the BRS group at post-operation 1st and 2nd day (P<0.05). Likewise, the concentrations of Mg2+, Na+ and K+ also varied significantly. The length of hospital was reduced, and the incidence of premature ventricular contractions (P = 0.042) and total complications (P = 0.016) were lower in group BRS. TRIAL REGISTRATION: The study was registered at clinicalTrials.gov with the number ChiCTR2000038077 on 09/09/2020.

Neonatal Survival After Serial Amnioinfusions for Bilateral Renal Agenesis: The Renal Anhydramnios Fetal Therapy Trial

Importance

Early anhydramnios during pregnancy, resulting from fetal bilateral renal agenesis, causes lethal pulmonary hypoplasia in neonates. Restoring amniotic fluid via serial amnioinfusions may promote lung development, enabling survival.

Objective

To assess neonatal outcomes of serial amnioinfusions initiated before 26 weeks' gestation to mitigate lethal pulmonary hypoplasia.

Design, Setting, and Participants

Prospective, nonrandomized clinical trial conducted at 9 US fetal therapy centers between December 2018 and July 2022. Outcomes are reported for 21 maternal-fetal pairs with confirmed anhydramnios due to isolated fetal bilateral renal agenesis without other identified congenital anomalies.

Exposure

Enrolled participants initiated ultrasound-guided percutaneous amnioinfusions of isotonic fluid before 26 weeks' gestation, with frequency of infusions individualized to maintain normal amniotic fluid levels for gestational age.

Main Outcomes and Measures

The primary end point was postnatal infant survival to 14 days of life or longer with dialysis access placement.

Results

The trial was stopped early based on an interim analysis of 18 maternal-fetal pairs given concern about neonatal morbidity and mortality beyond the primary end point despite demonstration of the efficacy of the intervention. There were 17 live births (94%), with a median gestational age at delivery of 32 weeks, 4 days (IQR, 32-34 weeks). All participants delivered prior to 37 weeks' gestation. The primary outcome was achieved in 14 (82%) of 17 live-born infants (95% CI, 44%-99%). Factors associated with survival to the primary outcome included a higher number of amnioinfusions (P = .01), gestational age greater than 32 weeks (P = .005), and higher birth weight (P = .03). Only 6 (35%) of the 17 neonates born alive survived to hospital discharge while receiving peritoneal dialysis at a median age of 24 weeks of life (range, 12-32 weeks).

Conclusions and Relevance

Serial amnioinfusions mitigated lethal pulmonary hypoplasia but were associated with preterm delivery. The lower rate of survival to discharge highlights the additional mortality burden independent of lung function. Additional long-term data are needed to fully characterize the outcomes in surviving neonates and assess the morbidity and mortality burden.

Trial Registration

ClinicalTrials.gov Identifier: NCT03101891.

Effect of 4% Albumin Solution vs Ringer Acetate on Major Adverse Events in Patients Undergoing Cardiac Surgery With Cardiopulmonary Bypass: A Randomized Clinical Trial

IMPORTANCE

In cardiac surgery, albumin solution may maintain hemodynamics better than crystalloids and reduce the decrease in platelet count and excessive fluid balance, but randomized trials are needed to compare the effectiveness of these approaches in reducing surgical complications.

OBJECTIVE

To assess whether 4% albumin solution compared with Ringer acetate as cardiopulmonary bypass prime and perioperative intravenous volume replacement solution reduces the incidence of major perioperative and postoperative complications in patients undergoing cardiac surgery.

DESIGN, SETTING, AND PARTICIPANTS

A randomized, double-blind, single-center clinical trial in a tertiary university hospital during 2017-2020 with 90-day follow-up postoperatively involving patients undergoing on-pump coronary artery bypass grafting; aortic, mitral, or tricuspid valve surgery; ascending aorta surgery without hypothermic circulatory arrest; and/or the maze procedure were randomly assigned to 2 study groups (last follow-up was April 13, 2020).

INTERVENTIONS

The patients received in a 1:1 ratio either 4% albumin solution (n = 693) or Ringer acetate solution (n = 693) as cardiopulmonary bypass priming and intravenous volume replacement intraoperatively and up to 24 hours postoperatively.

MAIN OUTCOMES AND MEASURES

The primary outcome was the number of patients with at least 1 major adverse event: death, myocardial injury, acute heart failure, resternotomy, stroke, arrhythmia, bleeding, infection, or acute kidney injury.

RESULTS

Among 1407 patients randomized, 1386 (99%; mean age, 65.4 [SD, 9.9] years; 1091 men [79%]; 295 women [21%]) completed the trial. Patients received a median of 2150 mL (IQR, 1598-2700 mL) of study fluid in the albumin group and 3298 mL (IQR, 2669-3500 mL) in the Ringer group. The number of patients with at least 1 major adverse event was 257 of 693 patients (37.1%) in the albumin group and 234 of 693 patients (33.8%) in the Ringer group (relative risk albumin/Ringer, 1.10; 95% CI, 0.95-1.27; P = .20), an absolute difference of 3.3 percentage points (95% CI, -1.7 to 8.4). The most common serious adverse events were pulmonary embolus (11 [1.6%] in the albumin group vs 8 [1.2%] in the Ringer group), postpericardiotomy syndrome (9 [1.3%] in both groups), and pleural effusion with intensive care unit or hospital readmission (7 [1.0%] in the albumin group vs 9 [1.3%] in the Ringer group).

CONCLUSIONS AND RELEVANCE

Among patients undergoing cardiac surgery with cardiopulmonary bypass, treatment with 4% albumin solution for priming and perioperative intravenous volume replacement solution compared with Ringer acetate did not significantly reduce the risk of major adverse events over the following 90 days. These findings do not support the use of 4% albumin solution in this setting.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02560519.

Rational Fluid Resuscitation in Sepsis for the Hospitalist: A Narrative Review

Administration of fluid is a cornerstone of supportive care for sepsis. Current guidelines suggest a protocolized approach to fluid resuscitation in sepsis despite a lack of strong physiological or clinical evidence to support it. Both initial and ongoing fluid resuscitation requires careful consideration, as fluid overload has been shown to be associated with increased risk for mortality. Initial fluid resuscitation should favor balanced crystalloids over isotonic saline, as the former is associated with decreased risk of renal dysfunction. Traditionally selected resuscitation targets, such as lactate elevation, are fraught with limitations. For developing or established septic shock, a focused hemodynamic assessment is needed to determine if fluid is likely to be beneficial. When initial fluid therapy is unable to achieve the blood pressure goal, initiation of early vasopressors and admission to intensive care should be favored over repetitive administration of fluid.

A Treatment to Eliminate SARS-CoV-2 Replication in Human Airway Epithelial Cells Is Safe for Inhalation as an Aerosol in Healthy Human Subjects

BACKGROUND

Low airway surface pH is associated with many airway diseases, impairs antimicrobial host defense, and worsens airway inflammation. Inhaled Optate is designed to safely raise airway surface pH and is well tolerated in humans. Raising intracellular pH partially prevents activation of SARS-CoV-2 in primary normal human airway epithelial (NHAE) cells, decreasing viral replication by several mechanisms.

METHODS

We grew primary NHAE cells from healthy subjects, infected them with SARS-CoV-2 (isolate USA-WA1/2020), and used clinical Optate at concentrations used in humans in vivo to determine whether Optate would prevent viral infection and replication. Cells were pretreated with Optate or placebo prior to infection (multiplicity of infection = 1), and viral replication was determined with plaque assay and nucleocapsid (N) protein levels. Healthy human subjects also inhaled Optate as part of a Phase 2a safety trial.

RESULTS

Optate almost completely prevented viral replication at each time point between 24 h and 120 h, relative to placebo, on both plaque assay and N protein expression (P < .001). Mechanistically, Optate inhibited expression of major endosomal trafficking genes and raised NHAE intracellular pH. Optate had no effect on NHAE cell viability at any time point. Inhaled Optate was well tolerated in 10 normal subjects, with no change in lung function, vital signs, or oxygenation.

CONCLUSIONS

Inhaled Optate may be well suited for a clinical trial in patients with pulmonary SARS-CoV-2 infection. However, it is vitally important for patient safety that formulations designed for inhalation with regard to pH, isotonicity, and osmolality be used. An inhalational treatment that safely prevents SARS-CoV-2 viral replication could be helpful for treating patients with pulmonary SARS-CoV-2 infection.

Clinical Effects of Balanced Crystalloids vs Saline in Adults With Diabetic Ketoacidosis: A Subgroup Analysis of Cluster Randomized Clinical Trials

IMPORTANCE

Saline (0.9% sodium chloride), the fluid most commonly used to treat diabetic ketoacidosis (DKA), can cause hyperchloremic metabolic acidosis. Balanced crystalloids, an alternative class of fluids for volume expansion, do not cause acidosis and, therefore, may lead to faster resolution of DKA than saline.

OBJECTIVE

To compare the clinical effects of balanced crystalloids with the clinical effects of saline for the acute treatment of adults with DKA.

DESIGN, SETTING, AND PARTICIPANTS

This study was a subgroup analysis of adults with DKA in 2 previously reported companion trials-Saline Against Lactated Ringer's or Plasma-Lyte in the Emergency Department (SALT-ED) and the Isotonic Solutions and Major Adverse Renal Events Trial (SMART). These trials, conducted between January 2016 and March 2017 in an academic medical center in the US, were pragmatic, multiple-crossover, cluster, randomized clinical trials comparing balanced crystalloids vs saline in emergency department (ED) and intensive care unit (ICU) patients. This study included adults who presented to the ED with DKA, defined as a clinical diagnosis of DKA, plasma glucose greater than 250 mg/dL, plasma bicarbonate less than or equal to 18 mmol/L, and anion gap greater than 10 mmol/L. Data analysis was performed from January to April 2020.

INTERVENTIONS

Balanced crystalloids (clinician's choice of Ringer lactate solution or Plasma-Lyte A solution) vs saline for fluid administration in the ED and ICU according to the same cluster-randomized multiple-crossover schedule.

MAIN OUTCOMES AND MEASURES

The primary outcome was time between ED presentation and DKA resolution, as defined by American Diabetes Association criteria. The secondary outcome was time between initiation and discontinuation of continuous insulin infusion.

RESULTS

Among 172 adults included in this secondary analysis of cluster trials, 94 were assigned to balanced crystalloids and 78 to saline. The median (interquartile range [IQR]) age was 29 (24-45) years, and 90 (52.3%) were women. The median (IQR) volume of isotonic fluid administered in the ED and ICU was 4478 (3000-6372) mL. Cumulative incidence analysis revealed shorter time to DKA resolution in the balanced crystalloids group (median time to resolution: 13.0 hours; IQR: 9.5-18.8 hours) than the saline group (median: 16.9 hours; IQR: 11.9-34.5 hours) (adjusted hazard ratio [aHR] = 1.68; 95% CI, 1.18-2.38; P = .004). Cumulative incidence analysis also revealed shorter time to insulin infusion discontinuation in the balanced crystalloids group (median: 9.8 hours; IQR: 5.1-17.0 hours) than the saline group (median: 13.4 hours; IQR: 11.0-17.9 hours) (aHR = 1.45; 95% CI, 1.03-2.03; P = .03).

CONCLUSIONS AND RELEVANCE

In this secondary analysis of 2 cluster randomized clinical trials, compared with saline, treatment with balanced crystalloids resulted in more rapid resolution of DKA, suggesting that balanced crystalloids may be preferred over saline for acute management of adults with DKA.

TRIAL REGISTRATION

ClinicalTrials.gov Identifiers: NCT02614040; NCT02444988.

[Simultaneous infusion of Ringer's lactate and Ringer's acetate and other drugs]

In this review, the administration of y-site infusion of crystalloid fluids such as Ringer's lactate and Ringer's acetate is discussed. Incompatibility may occur, and it can manifest as haziness, development of gas, colour change, precipitation and a decline of the concentration of the drug. It can also lead to phlebitis, pulmonary embolism and even death. Information on y-site compatibility with Ringer's lactate can be found, but there is a need for further research regarding y-site compatibility with Ringer's acetate.

Clinical Guideline Highlights for the Hospitalist: Maintenance Intravenous Fluids in Infants and Children

2018 American Academy of Pediatrics (AAP) Clinical Practice Guideline: Maintenance Intravenous Fluids in Children RELEASE DATE: November 26, 2018 PRIOR VERSION: Not Applicable DEVELOPER: Multidisciplinary subcommittee of experts assembled by the AAP FUNDING SOURCE: AAP TARGET POPULATION: Patients 28 days to 18 years of age requiring maintenance intravenous fluids (IVFs).

Clinical Guideline Highlights for the Hospitalist: The Use of Intravenous Fluids in the Hospitalized Adult

Intravenous Fluid Therapy in Adults in Hospital RELEASE DATE: December, 2013 PRIOR VERSION: Not Applicable DEVELOPER: Multidisciplinary Guideline Development Group within the United Kingdom's National Clinical Guideline Centre FUNDING SOURCE: National Institute for Health and Care Excellence TARGET POPULATION: Hospitalized adult patients.

Optimal crystalloid volume ratio for blood replacement for maintaining hemodynamic stability and lung function: an experimental randomized controlled study

BACKGROUND

Crystalloids are first line in fluid resuscitation therapy, however there is a lack of evidence-based recommendations on the volume to be administered. Therefore, we aimed at comparing the systemic hemodynamic and respiratory effects of volume replacement therapy with a 1:1 ratio to the historical 1:3 ratio.

METHODS

Anesthetized, ventilated rats randomly included in 3 groups: blood withdrawal and replacement with crystalloid in 1:1 ratio (Group 1, n = 11), traditional 1:3 ratio (Group 3, n = 12) and a control group with no interventions (Group C, n = 9). Arterial blood of 5% of the total blood volume was withdrawn 7 times, and replaced stepwise with different volume rations of Ringer's acetate, according to group assignments. Airway resistance (Raw), respiratory tissue damping (G) and tissue elastance (H), mean arterial pressure (MAP) and heart rate (HR) were assessed following each step of fluid replacement with a crystalloid (CR1-CR6). Lung edema index was measured from histological samples.

RESULTS

Raw decreased in Groups 1 and 3 following CR3 (p < 0.02) without differences between the groups. H elevated in all groups (p < 0.02), with significantly higher changes in Group 3 compared to Groups C and 1 (both p = 0.03). No differences in MAP or HR were present between Groups 1 and 3. Lung edema was noted in Group 3 (p < 0.05).

CONCLUSIONS

Fluid resuscitation therapy by administering a 1:1 blood replacement ratio revealed adequate compensation capacity and physiological homeostasis similar with no lung stiffening and pulmonary edema. Therefore, considering this ratio promotes the restrictive fluid administration in the presence of continuous and occult bleeding.

Intravenous Fluid to Prevent Hypotension in Patients Undergoing Elective Colonoscopy

Colonoscopy may be associated with hypotension during sedation leading to postoperative morbidity. However, no treatment is proven to ameliorate intraoperative hypotension for this procedure. We therefore conducted a randomized trial to determine the effect of intravenous fluid infusion on the incidence of hypotension during sedation for colonoscopy. With institutional approval, 160 patients presenting for elective colonoscopy were randomized to 1.5 ml/kg or 15 ml/kg Hartmann's solution before colonoscopy. All observers were blind to group allocation. The incidence of hypotension during sedation (29% vs 25%; P=0.59) and postoperative morbidity (nausea, vomiting, headache, drowsiness and dizziness) (41% vs 39%; P=0.75) did not differ between the two groups. Hypotensive patients were older, had a higher baseline systolic blood pressure, and were thirstier after fluid infusion than normotensive patients. This study does not support the use of 15 ml/kg Hartmann's solution to reduce the incidence of hypotension or postoperative morbidity in patients undergoing elective colonoscopy.

Haemodynamic effects of cold versus warm fluid bolus in healthy volunteers: a randomised crossover trial

OBJECTIVE

To test the hypothesis that changes in cardiac index and mean arterial pressure (MAP) during and after a fluid bolus (FB) are altered by fluid temperature.

DESIGN

Randomised, controlled, crossover trial.

SETTING

Research laboratory at Swedish teaching hospital.

PARTICIPANTS

Twenty-one healthy adult volunteers.

INTERVENTIONS

Subjects were randomly allocated to 500 mL of Ringer's acetate at room temperature (22°C; cold) or body temperature (38°C; warm).

MAIN OUTCOME MEASURES

For 2 hours after starting the FB, we measured cardiac index, MAP, systolic blood pressure, diastolic blood pressure and pulse rate (PR) continuously. We recorded temperature and O₂ saturation every 5 minutes during infusion and every 15 minutes thereafter. In a second session, volunteers crossed over.

RESULTS

During the first 15 minutes, mean cardiac index increased more with warm FB (0.09 L/min/m² [95% CI, 0.06-0.11] v 0.03 L/min/m² [95% CI, 0.01-0.06]; P < 0.001). This effect was mediated by a significant difference in mean PR (+0.80 beats/min [95% CI, 0.47-1.13] v -1.33 beats/ min [95% CI, -1.66 to -1.01]; P < 0.010). In contrast, MAP increased more with cold FB (4.02 mmHg [95% CI, 3.63-4.41] v 0.60 mmHg [95% CI, 0.26-0.95]; P < 0.001). Cardiac index and MAP returned to baseline after a median of 45.3 min (interquartile range [IQR], 10.7-60.7 min) and 27.7 min (IQR, 5.3-105.0 min), respectively, after cold FB, and by 15.8 min (IQR, 3.8-64.3 min) and 22.7 min (IQR, 3.3-105.0 min), respectively, after warm FB.

CONCLUSION

Intravenous FB at body temperature leads to a greater increase in cardiac index compared with room temperature, while the reverse applies to MAP. These findings imply that in healthy volunteers, when a room temperature FB is given, the temperature of the fluid rather than its volume accounts for most of the MAP increase.

TRIAL REGISTRATION

EudraCT no. 2016-002548-18 and Clinicaltrials.gov NCT03209271.

Beat the heat: Identification and Tx of heat-related illness

The prompt identification and treatment of heat-related illnesses and expedited transport to a higher level of care can be lifesaving. This article serves as a go-to guide.

Balanced 10% hydroxyethyl starch compared with balanced 6% hydroxyethyl starch and balanced crystalloid using a goal-directed hemodynamic algorithm in pancreatic surgery: A randomized clinical trial

BACKGROUND

While hydroxyethyl starch (HES) solutions are not recommended any longer in critically ill patients, data on efficacy and safety during surgery are still limited.

METHODS

In a randomized controlled trial 63 patients were assigned to receive 10% HES (130/0.42), 6% HES (130/0.42), or crystalloid within a goal-directed hemodynamic algorithm during pancreatic surgery. The primary endpoints were intraoperative volume of HES and time until fully on oral diet.

RESULTS

The trial was terminated early upon recommendation of an independent data monitoring committee due to futility for efficacy at a planned interim analysis. The intraoperative volume of HES was not different between 10% and 6% HES group (2000 [1500; 2250] vs 2250 [1750; 3000] mL, P=.059). However, considering an inhomogeneity of patient's body weight between HES groups, there was a significant difference in intraoperative volume of HES between 10% and 6% group after adjusting for patient's body weight (24.0 [21.6; 28.3] vs 33.3 [28.2; 46.2] mL kg BW, P = .002). Patients in the HES groups required less additional fluid after dose limit than those in the crystalloid group, resulting in lower intraoperative net balances. The time until fully on oral diet was not different between all study groups. Applying KDIGO oliguria criterion, patients receiving 10% HES had more AKI compared to patients receiving crystalloids (86.7 vs 45.0%, P = .010), whereas those receiving 6% HES and crystalloids did not differ (58.8 vs 45.0%, P = .253). Further explorative analyses using a gray-zone approach indicated that patients receiving 6% HES below 18.8 mL kg will not experience AKI with near certainty.

CONCLUSIONS

After adjusting for patient's body weight, patients receiving 6% HES required more volume of HES than patients receiving 10% HES. The relation of 140% represents very well the volume effect of a hyperoncotic 10% HES solution. Nonetheless, both HES solutions were similarly effective in reducing intraoperative fluid administration compared with crystalloid, but this did not result into differences in gastrointestinal outcomes. Patients receiving 10% HES showed an increased rate of AKI, whereas those receiving 6% HES and crystalloid did not differ. However, 6% HES should not be applied beyond 18 mL kg during surgery.

Differential effects of isotonic and hypotonic 4% albumin solution on intracranial pressure and renal perfusion and function

OBJECTIVES

Albumin is used to resuscitate trauma patients but may increase intracranial pressure (ICP). Its effects on renal blood flow and function are unknown. Our aim was to examine the effects of hypertonic albumin on ICP and renal function, and if any effects are due to the hypotonicity of the solution containing albumin or to albumin itself.

DESIGN, SETTING AND SUBJECTS

Cross-over, randomised controlled experimental study of six adult Merino ewes in the animal facility of a research institute.

METHOD

Sheep were implanted with flow probes around the pulmonary and renal arteries and an ICP monitoring catheter in a lateral cerebral ventricle. Conscious sheep received normal saline, commercially available hypotonic 4% albumin solution (4% Albumex [278 mOsm/kg]) or a novel isotonic 4% albumin solution (288 mOsm/kg), with at least 48 hours between each intervention.

RESULTS

Commercial hypotonic albumin solution increased ICP (by 8.5 mmHg [SEM, 2.1 mmHg]; P < 0.01), but neither isotonic albumin solution nor saline significantly changed ICP. The increase in ICP with hypotonic albumin solution was associated with an increase in central venous pressure (CVP) (by 5.4 mmHg [SEM, 0.6 mmHg]; P < 0.001), but no significant changes in cardiac output or stroke volume. None of the infusions changed renal blood flow, plasma creatinine level, creatinine clearance or plasma or urinary electrolyte levels.

CONCLUSION

Compared with saline or isotonic albumin solution, hypotonic albumin solution increased ICP and CVP, but did not alter arterial pressure, cardiac output renal blood flow or renal function. Our findings support the view that the tonicity of the albumin solution, rather than the albumin itself, is responsible for increasing ICP.

Preoperative fluid management in traumatic shock: A retrospective study for identifying optimal therapy of fluid resuscitation for aged patients

Fluid resuscitation was used on aged patients with traumatic shock in their early postoperative recovery. The present study aimed to assess whether different fluid resuscitation strategies had an influence on aged patients with traumatic shock.A total of 219 patients with traumatic shock were recruited retrospectively. Lactated Ringer and hydroxyethyl starch solution were transfused for fluid resuscitation before definite hemorrhagic surgery. Subjects were divided into 3 groups: group A: 72 patients were given aggressive fluid infusion at 20 to 30 mL/min to restore normal mean arterial pressure (MAP) of 65 to 75 mm Hg. Group B: 72 patients were slowly given restrictive hypotensive fluid infusion at 4 to 5 mL/min to maintain MAP of 50 to 65 mm Hg. Group C: 75 patients were given personalized infusion to achieve MAP of 75 to 85 mm Hg. Preoperative infusion volume, preoperative MAP, optimal initial points for surgery, postoperative shock time and mortality rates at 6 and 24 hours after surgery were determined.No significant difference in clinical characteristics was found among the 3 groups. Amount of preoperative infusion was considerably lower in the restrictive group (P < .01, compared with group A). A significant difference in preoperative infusion volume was found between the personalized and other 2 groups (P < .01, compared with groups A and B). Patients in the personalized resuscitation group achieved a higher preoperative MAP (P < .01 compared with Group B; P < .05, compared with group A) and required less prepared time for surgery (P < .01 compared with groups A and B). In addition, a lower mortality rate at 6 and 24 hours after operation was observed in the subjects with personalized therapy (P < .05, compared with group B).Personalized management of fluid resuscitation in traumatized aged patients with appropriate volume and speed of fluid transfusion, suggesting increased survival rate and less prepared time for surgery.

Limit Crystalloid Resuscitation after Traumatic Brain Injury

Patients with traumatic brain injury (TBI) are often resuscitated with crystalloids in the emergency department (ED) to maintain cerebral perfusion. The purpose of this study was to evaluate whether crystalloid resuscitation volume impacts mortality in TBI patients. This was a retrospective study of trauma patients with head abbreviated injury scale score ≥2, who received crystalloids during ED resuscitation between 2004 and 2013. Clinical characteristics and volume of crystalloids received in the ED were collected. Patients who received <2 L of crystalloids were categorized as low volume (LOW), whereas those who received ≥2 L were considered high volume (HIGH). Mortality and outcomes were compared. Multivariable regression analysis was used to determine the odds of mortality while controlling for confounders. Over 10 years, 875 patients met inclusion criteria. Overall mortality was 12.5 per cent. Seven hundred and forty-two (85%) were in the LOW cohort and 133 (15%) in the HIGH cohort. Gender and age were similar between the groups. The HIGH cohort had lower admission systolic blood pressure (128 vs 138 mm Hg, P = 0.001), lower Glasgow coma scale score (10 vs 12, P < 0.001), higher head abbreviated injury scale (3.8 vs 3.3, P < 0.001), and higher injury severity score (25 vs 18, P < 0.001). The LOW group had a lower unadjusted mortality (10 vs 26%, P < 0.001). Multivariable analysis adjusting for confounders demonstrated that those resuscitated with ≥2 L of crystalloids had increased odds of mortality (adjusted odds ratio 2.25, P = 0.005). Higher volume crystalloid resuscitation after TBI is associated with increased mortality, thus limited resuscitation for TBI patients may be indicated.

Maintenance fluid practices in paediatric intensive care units in Australia and New Zealand

BACKGROUND

Maintenance fluid administration is a common practice in paediatric intensive care units (PICUs), contributing to daily fluid intake and fluid balance, but little is known about this practice.

OBJECTIVES

To determine the volume and type of maintenance fluid delivered to PICU patients, and to assess changes in practice compared with a previous time point.

METHODS

A prospective, observational, single-day, point prevalence study of paediatric patients from 11 Australian and New Zealand PICUs, conducted in 2014.

RESULTS

Seventy-two patients were enrolled. The median age and weight of infants aged < 1 year (n = 34) were 2 months (interquartile range [IQR],1-4) and 5 kg (IQR, 4-6), respectively; while in children ≥ 1 year of age (n = 38), these were 4 years (IQR, 2-8) and 17 kg (IQR, 12-23), respectively. On the study day, 19 infants (56%) and 19 children aged ≥ 1 year (50%) received maintenance fluids. Infants received a median of 23 mL/kg (IQR, 12-45) of maintenance fluid in addition to 51 mL/kg (IQR, 40-72) of fluid and nutrition from other sources; maintenance fluids contributed 29% (IQR, 13%-60%) of the total daily fluid intake. Children ≥ 1 year of age received a median of 18 mL/kg (IQR, 9-37) of maintenance fluid in addition to 39 mL/kg (IQR, 25-53) of fluid and nutrition from other sources; maintenance fluids contributed 33% (IQR, 17%-69%) of the total daily fluid intake. When compared with similar data from 2011, there was no change in the amount of maintenance fluid given, which was administered mostly as isotonic fluids.

CONCLUSION

Maintenance fluid contributes about a third of total fluid administration in children in Australian and New Zealand PICUs and is mostly administered as isotonic solutions.

A Method to Administer Agents to the Larynx in an Awake Large Animal

PURPOSE

This research note describes an adapted experimental methodology to administer an exogenous agent to the larynx and upper airway of awake animals. The exogenous agent could be a perturbation. In the current study, the agent was isotonic saline. Isotonic saline was selected because it is safe, of similar composition to extracellular fluid, and used in voice studies. The described approach allowed large animals such as pigs to be comfortably restrained without chemical sedation or anesthesia for extended periods while receiving the agent.

METHOD

Six Sinclair pigs were successfully trained with positive reinforcement to voluntarily enter and then be restrained in a Panepinto Sling. Once restrained, the pigs accepted a nose cone that delivered nebulized isotonic saline. This procedure was repeated 3 times per day for 20 days. At the end of the study, the larynx and airway tissues were excised and examined using histology and transmission electron microscopy.

RESULTS

Pathology related to the procedure (i.e., nebulized inhaled isotonic saline or stress) was not identified in any examined tissues.

CONCLUSIONS

This methodology allowed for repeated application of exogenous agents to awake, unstressed animals. This method can be used repeatedly in the laboratory to test various therapeutics for safety, toxicity, and dosage. Future studies will specifically manipulate the type of agent to further our understanding of laryngeal pathobiology.

The effects of hypervolemic infusion on microcirculation perfusion of patients during laparoscopic colorectal surgery

The aim of this study is to assess the effects of hypervolemic infusion with different solutions on microcirculation perfusion during laparoscopic colorectal surgery.Thirty-six patients were randomly divided into Ringer lactate solution [RL] group, succinylated gelatin injection [Gel] group, and hypertonic saline hydroxyethyl starch 40 injection [HS] group. Hypervolemic infusion was performed during the induction period of general anesthesia. Arterial blood-gas parameters, noninvasive hemodynamics, gastric tonometry values, and central venous pressure (CVP) were compared at baseline (T1); the end of hypervolemic infusion (T2); 5 min (T3), 15 min (T4), 30 min (T5), and 60 min (T6) during pneumoperitoneum; 5 min (T7), 15 min (T8), and 25 min (T9) after pneumoperitoneum. Patients were also grouped by age for further comparisons.The hematocrit levels of all groups after T2 decreased. The gastric mucosal-arterial carbon dioxide partial pressure (Pg-aCO2) started to decrease after T2 and rebounded after T5. There was no difference in the gastric mucosal perfusion when compared between 3 groups. The blood Na of HS group increased significantly after T2, then gradually restored and returned to baseline by T8. The plasma bicarbonate (HCO3) levels of RL and Gel groups elevated from T2 to T7, after which they started to decrease, but this phenomenon was not significant in HS group. In both RL and Gel groups, blood pressure has a significant fluctuation in elder patients.Hypervolemic infusion of these solutions during the induction of anesthesia can improve gastric mucosal perfusion. HS can maintain a more stable hemodynamic effect when used with caution in patients with preoperative hypernatremia.

Perioperative administration of buffered versus non-buffered crystalloid intravenous fluid to improve outcomes following adult surgical procedures

BACKGROUND

Perioperative fluid strategies influence clinical outcomes following major surgery. Many intravenous fluid preparations are based on simple solutions, such as normal saline, that feature an electrolyte composition that differs from that of physiological plasma. Buffered fluids have a theoretical advantage of containing a substrate that acts to maintain the body's acid-base status - typically a bicarbonate or a bicarbonate precursor such as maleate, gluconate, lactate, or acetate. Buffered fluids also provide additional electrolytes, including potassium, magnesium, and calcium, more closely matching the electrolyte balance of plasma. The putative benefits of buffered fluids have been compared with those of non-buffered fluids in the context of clinical studies conducted during the perioperative period. This review was published in 2012, and was updated in 2017.

OBJECTIVES

To review effects of perioperative intravenous administration of buffered versus non-buffered fluids for plasma volume expansion or maintenance, or both, on clinical outcomes in adults undergoing all types of surgery.

SEARCH METHODS

We electronically searched the Clinicaltrials.gov major trials registry, the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 6) in the Cochrane Library, MEDLINE (1966 to June 2016), Embase (1980 to June 2016), and the Cumulative Index to Nursing and Allied Health Literature (CINAHL; 1982 to June 2016). We handsearched conference abstracts and, when possible, contacted leaders in the field. We reran the search in May 2017. We added one potential new study of interest to the list of 'Studies awaiting classification' and will incorporate this trial into formal review findings when we prepare the review update.

SELECTION CRITERIA

Only randomized controlled trials that compared buffered versus non-buffered intravenous fluids for surgical patients were eligible for inclusion. We excluded other forms of comparison such as crystalloids versus colloids and colloids versus different colloids.

DATA COLLECTION AND ANALYSIS

Two review authors screened references for eligibility, extracted data, and assessed risks of bias. We resolved disagreements by discussion and consensus, in collaboration with a third review author. We contacted trial authors to request additional information when appropriate. We presented pooled estimates for dichotomous outcomes as odds ratios (ORs) and for continuous outcomes as mean differences (MDs), with 95% confidence intervals (CIs). We analysed data via Review Manager 5.3 using fixed-effect models, and when heterogeneity was high (I² > 40%), we used random-effects models.

MAIN RESULTS

This review includes, in total, 19 publications of 18 randomized controlled trials with a total of 1096 participants. We incorporated five of those 19 studies (330 participants) after the June 2016 update. Outcome measures in the included studies were thematically similar, covering perioperative electrolyte status, renal function, and acid-base status; however, we found significant clinical and statistical heterogeneity among the included studies. We identified variable protocols for fluid administration and total volumes of fluid administered to patients intraoperatively. Trial authors variably reported outcome data at disparate time points and with heterogeneous patient groups. Consequently, many outcome measures are reported in small group sizes, reducing overall confidence in effect size, despite relatively low inherent bias in the included studies. Several studies reported orphan outcome measures. We did not include in the results of this review one large, ongoing study of saline versus Ringer's solution.We found insufficient evidence on effects of fluid therapies on mortality and postoperative organ dysfunction (defined as renal insufficiency leading to renal replacement therapy); confidence intervals were wide and included both clinically relevant benefit and harm: mortality (Peto OR 1.85, 95% CI 0.37 to 9.33; I² = 0%; 3 trials, 6 deaths, 276 participants; low-quality evidence); renal insufficiency (OR 0.82, 95% CI 0.34 to 1.98; I² = 0%; 4 trials, 22 events, 276 participants; low-quality evidence).We noted several metabolic differences, including a difference in postoperative pH measured at end of surgery of 0.05 units - lower in the non-buffered fluid group (12 studies with a total of 720 participants; 95% CI 0.04 to 0.07; I² = 61%). However, this difference was not maintained on postoperative day one. We rated the quality of evidence for this outcome as moderate. We observed a higher postoperative serum chloride level immediately after operation, with use of non-buffered fluids reported in 10 studies with a total of 530 participants (MD 6.77 mmol/L, 95% CI 3.38 to 10.17), and this difference persisted until day one postoperatively (five studies with a total of 258 participants; MD 8.48 mmol/L, 95% CI 1.08 to 15.88). We rated the quality of evidence for this outcome as moderate.

AUTHORS' CONCLUSIONS

Current evidence is insufficient to show effects of perioperative administration of buffered versus non-buffered crystalloid fluids on mortality and organ system function in adult patients following surgery. Benefits of buffered fluid were measurable in biochemical terms, particularly a significant reduction in postoperative hyperchloraemia and metabolic acidosis. Small effect sizes for biochemical outcomes and lack of correlated clinical follow-up data mean that robust conclusions on major morbidity and mortality associated with buffered versus non-buffered perioperative fluid choices are still lacking. Larger studies are needed to assess these relevant clinical outcomes.

Effect of Intravenously Administered Crystalloid Solutions on Acid-Base Balance in Domestic Animals

Intravenous fluid therapy can alter plasma acid-base balance. The Stewart approach to acid-base balance is uniquely suited to identify and quantify the effects of the cationic and anionic constituents of crystalloid solutions on plasma pH. The plasma strong ion difference (SID) and weak acid concentrations are similar to those of the administered fluid, more so at higher administration rates and with larger volumes. A crystalloid's in vivo effects on plasma pH are described by 3 general rules: SID > [HCO3-] increases plasma pH (alkalosis); SID < [HCO3-] decreases plasma pH (alkalosis); and SID = [HCO3-] yields no change in plasma pH. The in vitro pH of commercially prepared crystalloid solutions has little to no effect on plasma pH because of their low titratable acidity. Appreciation of IV fluid composition and an understanding of basic physicochemical principles provide therapeutically valuable insights about how and why fluid therapy can produce and correct alterations of plasma acid-base equilibrium. The ideal balanced crystalloid should (1) contain species-specific concentrations of key electrolytes (Na+ , Cl- , K+ , Ca++ , Mg++ ), particularly Na+ and Cl- ; (2) maintain or normalize acid-base balance (provide an appropriate SID); and (3) be isosmotic and isotonic (not induce inappropriate fluid shifts) with normal plasma.

REstricted Fluid REsuscitation in Sepsis-associated Hypotension (REFRESH): study protocol for a pilot randomised controlled trial

BACKGROUND

Guidelines recommend an initial intravenous (IV) fluid bolus of 30 ml/kg isotonic crystalloid for patients with sepsis and hypotension. However, there is a lack of evidence from clinical trials to support this. Accumulating observational data suggest harm associated with the injudicious use of fluids in sepsis. There is currently equipoise regarding liberal or restricted fluid-volume resuscitation as first-line treatment for sepsis-related hypotension. A randomised trial comparing these two approaches is, therefore, justified.

METHODS/DESIGN

The REstricted Fluid REsuscitation in Sepsis-associated Hypotension trial (REFRESH) is a multicentre, open-label, randomised, phase II clinical feasibility trial. Participants will be patients presenting to the emergency departments of Australian metropolitan hospitals with suspected sepsis and a systolic blood pressure of < 100 mmHg, persisting after a 1000-ml fluid bolus with isotonic crystalloid. Participants will be randomised to either a second 1000-ml fluid bolus (standard care) or maintenance rate fluid only, with the early commencement of a vasopressor infusion to maintain a mean arterial pressure of > 65 mmHg, if required (restricted fluid). All will receive further protocolised fluid boluses (500 ml or 250 ml, respectively), if required during the 6-h study period. The primary outcome measure is total volume administered in the first 6 h. Secondary outcomes include fluid volume at 24 h, organ support 'free days' to day 28, 90-day mortality, and a range of feasibility and process-of-care measures. Participants will also undergo serial measurement, over the first 24 h, of biomarkers of inflammation, endothelial cell activation and glycocalyx degradation for comparison between the groups.

DISCUSSION

This is the first randomised trial examining fluid volume for initial resuscitation in septic shock in an industrialised country. A pragmatic, open-label design will establish the feasibility of undertaking a large, international, multicentre trial with sufficient power to assess clinical outcomes. The embedded biomarker study aims to provide mechanistic plausibility for a larger trial by defining the effects of fluid volume on markers of systemic inflammation and the vascular endothelium.

TRIAL REGISTRATION

Australia and New Zealand Clinical Trials Registry, ID: ACTRN12616000006448. Registered on 12 January 2016.

Multidisciplinary team learning in the management of the morbidly adherent placenta: outcome improvements over time

BACKGROUND

Morbidly adherent placenta (MAP) is a serious obstetric complication causing mortality and morbidity.

OBJECTIVE

To evaluate whether outcomes of patients with MAP improve with increasing experience within a well-established multidisciplinary team at a single referral center.

STUDY DESIGN

All singleton pregnancies with pathology-confirmed MAP (including placenta accreta, increta, or percreta) managed by a multidisciplinary team between January 2011 and August 2016 were included in this retrospective study. Turnover of team members was minimal, and cases were divided into 2 time periods so as to compare 2 similarly sized groups: T1 = January 2011 to April 2014 and T2 = May 2014 to August 2016. Outcome variables were estimated blood loss, units of red blood cell transfused, volume of crystalloid transfused, massive transfusion protocol activation, ureter and bowel injury, and neonatal birth weight. Comparisons and adjustments were made by use of the Student t test, Mann-Whitney U test, χ² test, analysis of covariance, and multinomial logistic regression.

RESULTS

A total of 118 singleton pregnancies, 59 in T1 and 59 in T2, were managed during the study period. Baseline patient characteristics were not statistically significant. Forty-eight of 59 (81.4%) patients in T1 and 42 of 59 (71.2%) patients in T2 were diagnosed with placenta increta/percreta. The median [interquartile range] estimated blood loss (T1: 2000 [1475-3000] vs T2: 1500 [1000-2700], P = .04), median red blood cell transfusion units (T1: 2.5 [0-7] vs T2: 1 [0-4], P = .02), and median crystalloid transfusion volume (T1: 4200 [3600-5000] vs T2: 3400 [3000-4000], P < .01) were significantly less in T2. Also, a massive transfusion protocol was instituted more frequently in T1: 15/59 (25.4%) vs 3/59 (5.1%); P < .01. Neonatal outcomes and surgical complications were similar between the 2 groups.

CONCLUSION

Our study shows that patient outcomes are improved over time with increasing experience within a well-established multidisciplinary team performing 2-3 cases per month. This suggests that small, collective changes in team dynamics lead to continuous improvement of clinical outcomes. These findings support the development of centers of excellence for MAP staffed by stable, core multidisciplinary teams, which should perform a significant number of these procedures on an ongoing basis.

Maintenance fluid therapy in a tertiary hospital: A prevalence study

OBJECTIVE

To assess the types of maintenance fluids used in our hospital, comparing their volume and composition to the standards recommended by the guidelines.

MATERIAL AND METHODS

Observational, cross-sectional study. Volume and type of fluid therapy administered during 24h to patients admitted to various hospital departments were recorded. Patients receiving fluid therapy because of water-electrolyte imbalance were excluded.

RESULTS

Out of 198 patients registered, 74 (37.4%) were excluded because they did not meet the criteria for inclusion. Mean administered volume was 2,500cc/day. Mean daily glucose dose was 36g per 24h (SD: 31.4). The most frequent combination included normal saline solution (NSS) and glucose 5% (64.4%). Mean daily dose of sodium and chlorine was, respectively, 173mEq (SD: 74.8) and 168mEq (SD: 75), representing a surplus daily dose of +87.4mEq and +85mEq. Potassium, magnesium and calcium daily deficit was, respectively, -50mEq, -22mEq and -21mEq per day. Buffer administration was exceptional, bicarbonate (2.29%), acetate (1.29%), lactate (1.15%) and gluconate (1.10%) being the buffering agents most frequently used.

CONCLUSION

NNS is the most frequently used solution. In contrast to excess doses of sodium and chlorine, there is a great deficit of other ions, buffering agents and caloric intake in the fluid therapy regimens that are usually prescribed.

Use of intravenous fluids/solutions: a narrative review

OBJECTIVE

Intravenous fluids are broadly categorized into colloids and crystalloids. The aim of this review is to present under a clinical point of view the characteristics of intravenous fluids that make them more or less appropriate either for maintaining hydration when enteral intake is contraindicated or for treating hypovolemia.

METHODS

We considered randomized trials and meta-analyses as well as narrative reviews evaluating the effects of colloids or crystalloids in patients with hypovolemia or as maintenance fluids published in the PubMed and Cochrane databases.

RESULTS

Clinical studies have not shown a greater clinical benefit of albumin solutions compared with crystalloid solutions. Furthermore, albumin and colloid solutions may impair renal function, while there is no evidence that the administration of colloids reduces the risk of death compared with resuscitation with crystalloids in patients with trauma, burns or following surgery. Among crystalloids, normal saline is associated with the development of hyperchloremia-induced impairment of kidney function and metabolic acidosis. On the other hand, the other commonly used crystalloid solution, the Ringer's Lactate, has certain indications and contraindications. These matters, along with the basic principles of the administration of potassium chloride and bicarbonate, are meticulously discussed in the review.

CONCLUSIONS

Intravenous fluids should be dealt with as drugs, as they have specific clinical indications, contraindications and adverse effects.

Intravenous nutrients for preventing inadvertent perioperative hypothermia in adults

BACKGROUND

Inadvertent perioperative hypothermia (a drop in core temperature to below 36°C) occurs because normal temperature regulation is disrupted during surgery, mainly because of the effects of anaesthetic drugs and exposure of the skin for prolonged periods. Many different ways of maintaining body temperature have been proposed, one of which involves administration of intravenous nutrients during the perioperative period that may reduce heat loss by increasing metabolism, thereby increasing heat production.

OBJECTIVES

To assess the effectiveness of preoperative or intraoperative intravenous nutrients in preventing perioperative hypothermia and its complications during surgery in adults.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; November 2015) in the Cochrane Library; MEDLINE, Ovid SP (1956 to November 2015); Embase, Ovid SP (1982 to November 2015); the Institute for Scientific Information (ISI) Web of Science (1950 to November 2015); and the Cumulative Index to Nursing and Allied Health Literature (CINAHL, EBSCO host; 1980 to November 2015), as well as the reference lists of identified articles. We also searched the Current Controlled Trials website and ClincalTrials.gov.

SELECTION CRITERIA

Randomized controlled trials (RCTs) of intravenous nutrients compared with control or other interventions given to maintain normothermia in adults undergoing surgery.

DATA COLLECTION AND ANALYSIS

Two review authors extracted data and assessed risk of bias for each included trial, and a third review author checked details if necessary. We contacted some study authors to request additional information.

MAIN RESULTS

We included 14 trials (n = 565), 13 (n = 525) of which compared intravenous administration of amino acids to a control (usually saline solution or Ringer's lactate). The remaining trial (n = 40) compared intravenous administration of fructose versus a control. We noted much variation in these trials, which used different types of surgery, variable durations of surgery, and different types of participants. Most trials were at high or unclear risk of bias owing to inappropriate or unclear randomization methods, and to unclear participant and assessor blinding. This may have influenced results, but it is unclear how results might have been influenced.No trials reported any of our prespecified primary outcomes, which were risk of hypothermia and major cardiovascular events. Therefore, we decided to analyse data related to core body temperature instead as a primary outcome. It was not possible to conduct meta-analysis of data related to amino acid infusion for the 60-minute and 120-minute time points, as we observed significant statistical heterogeneity in the results. Some trials showed that higher temperatures were associated with amino acids, but not all trials reported statistically significant results, and some trials reported the opposite result, where the amino acid group had a lower core temperature than the control group. It was possible to conduct meta-analysis for six studies (n = 249) that provided data relating to the end of surgery. Amino acids led to a statistically significant increase in core temperature in comparison to those receiving control (MD = 0.46°C 95% CI 0.33 to 0.59; I2 0.0%; random-effects; moderate quality evidence).Three trials (n = 155) reported shivering as an outcome. Meta-analysis did not show a clear effect, and so it is uncertain whether amino acids reduce the risk of shivering (RR 0.36, 95% CI 0.13 to 1.00; I2 = 93%; random-effects model; very low-quality evidence).

AUTHORS' CONCLUSIONS

Intravenous amino acids may keep participants up to a half-degree C warmer than the control. This difference was statistically significant at the end of surgery, but not at other time points. However, the clinical importance of this finding remains unclear. It is also unclear whether amino acids have any effect on the risk of shivering and if intravenous nutrients confer any other benefits or harms, as high-quality data about these outcomes are lacking.

Response of fibroblast growth factor 23 to volume interventions in arterial hypertension and diabetic nephropathy

Fibroblast growth factor 23 (FGF-23) rises progressively in chronic kidney disease and is associated with adverse cardiovascular outcomes. FGF-23 putatively induces volume retention by upregulating the sodium-chloride cotransporter (NCC). We studied whether, conversely, interventions in volume status affect FGF-23 concentrations.We performed a post hoc analysis of 1) a prospective saline infusion study with 12 patients with arterial hypertension who received 2 L of isotonic saline over 4 hours, and 2) a randomized controlled trial with 45 diabetic nephropathy (DN) patients on background angiotensin-converting enzyme -inhibition (ACEi), who underwent 4 6-week treatment periods with add-on hydrochlorothiazide (HCT) or placebo, combined with regular sodium (RS) or low sodium (LS) diet in a cross-over design. Plasma C-terminal FGF-23 was measured by ELISA (Immutopics) after each treatment period in DN and before and after saline infusion in hypertensives.The patients with arterial hypertension were 45 ± 13 (mean ± SD) years old with an estimated glomerular filtration rate (eGFR) of 101 ± 18 mL/min/1.73 m. Isotonic saline infusion did not affect FGF-23 (before infusion: 68 median [first to third quartile: 58-97] relative unit (RU)/mL, after infusion: 67 [57-77] RU/mL, P = 0.37). DN patients were 65 ± 9 years old. During ACEi + RS treatment, eGFR was 65 ± 25 mL/min/1.73 m and albuminuria 649 mg/d (230-2008 mg/d). FGF23 level was 94 (73-141) RU/mL during ACEi therapy. FGF-23 did not change significantly by add-on HCT (99 [74-148] RU/mL), LS diet (99 [75-135] RU/mL), or their combination (111 [81-160] RU/mL, P = 0.15).Acute and chronic changes in volume status did not materially change FGF-23 in hypertensive patients and DN, respectively. Our data do not support a direct feedback loop between volume status and FGF-23 in hypertension or DN.

Fluid Choice Matters in Critically-ill Patients with Acute Pancreatitis: Lactated Ringer's vs. Isotonic Saline

OBJECTIVES

To investigate the effect of different crystal- loid solutions on clinical outcomes in critically-ill patients with acute pancreatitis (AP).

METHODS

We conducted a retrospective study of patients with AP admitted to the ICU using the Multiparameter Intelligent Monitoring in Intensive Care III (MIMIC-III) database. We investigated the effect of fluid type; lactated ringer's (LR) vs. isotonic saline (IS) on hospital mortality rates, and ICU length of stay (LOS).

RESULTS

Hospital mortality of the 198 included patients was 12%. For fluid type, 32.9% were resuscitated with LR vs. 67.1% with IS. Hospital mortality was lower in the LR group (5.8%) vs. 14.9% for IS group, odds ratio of 3.10 [P=0.041]. This effect was still observed after adjusting for confounders. However, ICU LOS was longer in LR compared to IS group; 6.2±6.9 vs. 4.2±4.49 days respectively [P= 0.020].

CONCLUSION

The type of fluid used for resuscitation in AP may affect the outcome. LR may have survival benefit over IS in critically-ill patients with AP. [Full article available at http://rimed.org/rimedicaljournal-2016-10.asp].

The impact of hematocrit on oxygenation-sensitive cardiovascular magnetic resonance

BACKGROUND

Oxygenation-sensitive (OS) Cardiovascular Magnetic Resonance (CMR) is a promising utility in the diagnosis of heart disease. Contrast in OS-CMR images is generated through deoxyhemoglobin in the tissue, which is negatively correlated with the signal intensity (SI). Thus, changing hematocrit levels may be a confounder in the interpretation of OS-CMR results. We hypothesized that hemodilution confounds the observed signal intensity in OS-CMR images.

METHODS

Venous and arterial blood from five pigs was diluted with lactated Ringer solution in 10 % increments to 50 %. The changes in signal intensity (SI) were compared to changes in blood gases and hemoglobin concentration. We performed an OS-CMR scan in 21 healthy volunteers using vasoactive breathing stimuli at baseline, which was then repeated after rapid infusion of 1 L of lactated Ringer's solution within 5-8 min. Changes of SI were measured and compared between the hydration states.

RESULTS

The % change in SI from baseline for arterial (r = -0.67, p < 0.0001) and venous blood (r = -0.55, p = 0.002) were negatively correlated with the changes in hemoglobin (Hb). SI changes in venous blood were also associated with SO2 (r = 0.68, p < 0.0001) and deoxyHb concentration (-0.65, p < 0.0001). In healthy volunteers, rapid infusion resulted in a significant drop in the hemoglobin concentration (142.5 ± 15.2 g/L vs. 128.8 ± 15.2 g/L; p < 0.0001). Baseline myocardial SI increased by 3.0 ± 5.7 % (p = 0.026) following rapid infusion, and in males there was a strong association between the change in hemoglobin concentration and % changes in SI (r = 0.82, p = 0.002). After hyperhydration, the SI response after hyperventilation was attenuated (HV, p = 0.037), as was the maximum SI increase during apnea (p = 0.012). The extent of SI attenuation was correlated with the reduction in hemoglobin concentration at the end of apnea (r = 0.55, p = 0.012) for all subjects and at maximal SI (r = 0.63, p = 0.037) and the end of breath-hold (r = 0.68, p = 0.016) for males only.

CONCLUSION

In dynamic studies using oxygenation-sensitive CMR, the hematocrit level affects baseline signal intensity and the observed signal intensity response. Thus, the hydration status of the patient may be a confounder for OS-CMR image analysis.

Hypertonic hydroxyethyl starch solution for hypovolaemia correction following heart surgery

Background. The aim of the study was to evaluate the effect of hypertonic NaCl hydroxyethyl starch solution on haemodynamics and cardiovascular parameters in the early postoperative period in patients for correction of hypovolaemia after heart surgery. Methods. Eighty patients undergoing myocardial revascularisation at the Clinic of Cardiac Surgery of the Heart Centre (Kaunas University of Medicine) were randomly divided into two groups. The HyperHaes® group (n = 40) received 250 ml 7.2% NaCl/6% HES solution and the control Ringer's acetate group (n = 40) received placebo (500ml Ringer's acetate solution) for volume correction after the surgery. Results. After infusion of HyperHaes® solution, cardiac index increased from 2.69 (0.7) to 3.52 (0.8)l/min/m2, systemic vascular resistance index, pulmonary vascular resistance index and the gradient between central and peripheral temperature decreased, and oxygen transport parameters improved. Ringer's group patients needed more intensive infusion therapy (4050.0 (1102.2) ml in the Ringer's group, 3513.7(762.5) ml in the HyperHaes® group). During the first 24 hours postoperatively, diuresis was significantly higher in the HyperHaes® group (3640.0 (1122.9) ml and 2736.0 (900.7) ml), total fluid balance was lower in HyperHaes® group (1405.6 (1519.0) ml and 2718.3 (1508.0) ml, respectively). After the infusion of HyperHaes ® solution, no adverse events were noted. Conclusions. HyperHaes ® solution had a positive effect on haemodynamic parameters and microcirculation. Oxygen transport was more effective after HyperHaes® solution infusion. Higher diuresis, lower need for the infusion therapy for the first 24 hours and lower total fluid balance were determined in the HyperHaes® group. No adverse effects were observed after HyperHaes® solution infusion. Perfusion (2007) 22, 121—127.

Hypertonic salt solution for peri-operative fluid management

BACKGROUND

Fluid excess may place people undergoing surgery at risk for various complications. Hypertonic salt solution (HS) maintains intravascular volume with less intravenous fluid than isotonic salt (IS) solutions, but may increase serum sodium. This review was published in 2010 and updated in 2016.

OBJECTIVES

To determine the benefits and harms of HS versus IS solutions administered for fluid resuscitation to people undergoing surgery.

SEARCH METHODS

In this updated review we have searched the Cochrane Central Register of Controlled Trials (CENTRAL; Issue 4, 2016); MEDLINE (January 1966 to April 2016); EMBASE (January 1980 to April 2016); LILACS (January 1982 to April 2016) and CINAHL (January 1982 to April 2016) without language restrictions. We conducted the original search on April 30th, 2007, and reran it on April 8th, 2016.

SELECTION CRITERIA

We have included randomized clinical trials (RCTs) comparing HS to IS in people undergoing surgery, irrespective of blinding, language, and publication status.

DATA COLLECTION AND ANALYSIS

Two independent review authors read studies that met our selection criteria. We collected study information and data using a data collection sheet with predefined parameters. We have assessed the impact of HS administration on mortality, organ failure, fluid balance, serum sodium, serum osmolarity, diuresis and physiologic measures of cardiovascular function. We have pooled the data using the mean difference (MD) for continuous outcomes. We evaluated heterogeneity between studies by I² percentage. We consider studies with an I² of 0% to 30% to have no or little heterogeneity, 30% to 60% as having moderate heterogeneity, and more than 60% as having high heterogeneity. In studies with low heterogeneity we have used a fixed-effect model, and a random-effects model for studies with moderate to high heterogeneity.

MAIN RESULTS

We have included 18 studies with 1087 participants of whom 545 received HS compared to 542 who received IS. All participants were over 18 years of age and all trials excluded high-risk patients (ASA IV). All trials assessed haematological parameters peri-operatively and up to three days post-operatively.There were three (< 1%) deaths reported in the IS group and four (< 1%) in the HS group, as assessed at 90 days in one study. There were no reports of serious adverse events. Most participants were in a positive fluid balance postoperatively (4.4 L IS and 2.5 L HS), with the excess significantly less in HS participants (MD -1.92 L, 95% confidence interval (CI) -2.61 to -1.22 L; P < 0.00001). IS participants received a mean volume of 2.4 L and HS participants received 1.49 L, significantly less fluid than IS-treated participants (MD -0.91 L, 95% CI -1.24 to -0.59 L; P < 0.00001). The maximum average serum sodium ranged between 138.5 and 159 in HS groups compared to between 136 and 143 meq/L in the IS groups. The maximum serum sodium was significantly higher in HS participants (MD 7.73, 95% CI 5.84 to 9.62; P < 0.00001), although the level remained within normal limits (136 to 146 meq/L).A high degree of heterogeneity appeared to be related to considerable differences in the dose of HS between studies. The quality of the evidence for the outcomes reported ranged from high to very low. The risk of bias for many of the studies could not be determined for performance and detection bias, criteria that we assess as likely to impact the study outcomes.

AUTHORS' CONCLUSIONS

HS reduces the volume of intravenous fluid required to maintain people undergoing surgery but transiently increases serum sodium. It is not known if HS affects survival and morbidity, but this should be examined in randomized controlled trials that are designed and powered to test these outcomes.

Changes in intravenous fluid use patterns in Australia and New Zealand: evidence of research translating into practice

OBJECTIVES

To describe changes in the use of intravenous (IV) fluid by quantity and type in different regions of Australia and New Zealand.

DESIGN, SETTING AND PARTICIPANTS

We conducted a retrospective ecological study examining regional and temporal trends in IV fluid consumption across Australia and New Zealand over the periods 2012-2013 and 2013- 2014, using national proprietary sales data as a surrogate for consumption, and demographic data from the public domain.

RESULTS

More than 13.3 million litres of IV fluid were consumed in Australia and New Zealand in 2012-2013, and more than 13.9 million litres in 2013-2014, with colloid solutions accounting for < 2%. There was marked regional variation in consumption of fluids, by volumes and proportions used, when standardised to overall Australian and New Zealand values. There was no significant change in the overall volume of crystalloid solutions consumed but there was a significant decrease (9%; P = 0.02) in the ratio of unbalanced to balanced crystalloid solutions consumed. Consumption of all forms of colloid solutions decreased, with a 12% reduction overall (P = 0.02), primarily driven by a 67% reduction in the consumption of hydroxyethyl starch (HES) solutions.

CONCLUSIONS

The amount and type of IV fluid use, as determined by fluid sales, is highly variable across Australia and New Zealand. However, overall use of balanced crystalloid solutions is increasing and the use of HES has decreased dramatically.

Hearing Loss after Spinal Anesthesia: The Effect of Different Infusion Solutions

OBJECTIVE: We speculate that the preoperative volume replacement with a convenient solution may protect the inner ear function after spinal anesthesia.

METHODS: The patients were randomized in a single-blind fashion into two groups: group LR (n = 40) received lactated Ringer's and group GF (n = 40) received gelatin polysuccinate 4% (Gelofusine). Spinal anesthesia was performed with a 25 G Quincke needle and was given bupivacaine 0.5% 10 mg and fentanyl 25 jxg. Audio-grams were performed preoperatively and 2 days postoperatively.

RESULTS: The overall incidence of hearing loss was 7.5%. The hearing loss was unilateral in two and bilateral in four patients. Hearing loss occurred within the low-frequency range and the hearing thresholds returned to normal by the fifth postoperative day.

CONCLUSIONS: Although the incidence of hearing loss for the lactated Ringer's group was higher than the Gelofusine group, there was no statistically significant difference between the groups. For medicolegal and ethical reasons, patients should be informed about the possibility of hearing loss after spinal anesthesia.

Does the infusion rate of fluid affect rapidity of mean arterial pressure restoration during controlled hemorrhage

OBJECTIVE

This study aimed to compare 2 fluid infusion rates of lactated Ringer (LR) and hydroxyethyl starch (HES) 130/0.4 on hemodynamic restoration at the early phase of controlled hemorrhagic shock.

METHODS

Fifty-six anesthetized and ventilated piglets were bled until mean arterial pressure (MAP) reached 40 mm Hg. Controlled hemorrhage was maintained for 30 minutes. After this period, 4 resuscitation groups were studied (n=14 for each group): HES infused at 1 or 4mL/kg per minute or LR1 infused at 1 or 4mL/kg per minute until baseline MAP was restored. Hemodynamic assessment using PiCCO monitoring and biological data were collected.

RESULTS

Time to restore baseline MAP ±10% was significantly lower in LR4 group (11±11 minutes) compared to LR1 group (41±25 minutes) (P=.0004). Time to restore baseline MAP ±10% was significantly lower in HES4 group (4±3 minutes) compared to HES1 (11±4 minutes) (P=.0003). Time to restore baseline MAP ±10% was significantly lower with HES vs LR whatever the infusion rate. No statistically significant difference was observed in cardiac output, central venous saturation, extravascular lung water, and arterial lactate between 4 and 1 mL/kg per minute groups.

CONCLUSIONS

In this controlled hemorrhagic shock model, a faster infusion rate (4 vs 1mL/kg per minute) significantly decreased the time for restoring baseline MAP, regardless of the type of infused fluid. The time for MAP restoration was significantly shorter for HES as compared to LR whatever the fluid infusion rate.

WITHDRAWN: Nasal saline irrigations for the symptoms of chronic rhinosinusitis

Review withdrawn from Issue 4, 2016. Review replaced by 'Saline irrigation for chronic rhinosinusitis' (Chong 2016).

The editorial group responsible for this previously published document have withdrawn it from publication.

Impact of Albumin on Coagulation Competence and Hemorrhage During Major Surgery: A Randomized Controlled Trial

For patients exposed to a massive blood loss during surgery, maintained coagulation competence is important. It is less obvious whether coagulation competence influences bleeding during elective surgery where patients are exposed to infusion of a crystalloid or a colloid. This randomized controlled trial evaluates whether administration of 5% human albumin (HA) or lactated Ringer solution (LR) affects coagulation competence and in turn blood loss during cystectomy due to bladder cancer. Forty patients undergoing radical cystectomy were included to receive either 5% HA (n = 20) or LR (n = 20). Nineteen patients were analyzed in the HA group and 20 patients in the lactated Ringer group. Blinded determination of the blood loss was similar in the 2 groups of patients: 1658 (800-3300) mL with the use of HA and 1472 (700-4330) mL in the lactated Ringer group (P = 0.45). Yet, by thrombelastography (TEG) evaluated coagulation competence, albumin affected clot growth (TEG-angle 69 ± 5 vs 74° ± 3°, P < 0.01) and strength (TEG-MA: 59 ± 6 vs 67 ± 6 mm, P < 0.001) more than LR. Furthermore, by multivariate linear regression analyses reduced TEG-MA was independently associated with the blood loss (P = 0.042) while administration of albumin was related to the changes in TEG-MA (P = 0.029), aPPT (P < 0.022), and INR (P < 0.033). This randomized controlled trial demonstrates that administration of HA does not affect the blood loss as compared to infusion of LR. Also the use of HA did not affect the need for blood transfusion, the incidence of postoperative complications, or the hospital in-stay. Yet, albumin decreases coagulation competence during major surgery and the blood loss is related to TEG-MA rather than to plasma coagulation variables.

Plasma pro-atrial natriuretic peptide to indicate fluid balance during cystectomy: a prospective observational study

OBJECTIVES

During surgery the volume of administered fluid is debated. Pro-atrial natriuretic peptide (proANP) is released by atrial distension, and we evaluated the relationship between changes in proANP associated with perioperative fluid balance.

DESIGN

Prospective observational study.

SETTING

One university/tertiary centre.

PARTICIPANTS

The study included patients who underwent radical cystectomy. Plasma for determination of proANP was obtained before surgery, after resection of the bladder, and at the end of surgery for 20 robotic-assisted radical cystectomy (RARC) and 20 open radical cystectomy (ORC) procedures.

RESULTS

The blood loss was 1871 (95% CI 1267 to 2475) vs 589 mL (378 to 801) in the ORC and RARC groups (p=0.001), respectively, and fluid balance was positive by 1518 mL (1215 to 1821) during ORC, and by 1858 mL (1461 to 2255) during RARC (p=0.163). Yet, at the end of ORC, plasma proANP was reduced by 23% (14% to 32%, p=0.001), while plasma proANP did not change significantly during RARC. Thus, plasma proANP was associated both with the perioperative blood loss (r= -0.475 (0.632 to -0.101), p=0.002), and with fluid balance (r=0.561 (0.302 to 0.740), p=0.001), indicating that a stable plasma proANP required a fluid surplus by 2.4 L (2.0 to 2.7).

CONCLUSIONS

There was a correlation between intraoperative haemorrhage and a decrease in plasma proANP and, taking plasma proANP to indicate filling of the heart, about 2.5 L surplus volume of lactated Ringer's solution appears to maintain cardiac preload during cystectomy.

TRIAL REGISTRATION NUMBER

EudraCT (2012-005040-20), Results.

[Sodium chloride 0.9%: nephrotoxic crystalloid?]

Sodium chloride 0.9%, often incorrectly called physiological saline, contains higher concentration of chloride compared to plasma. It is known that the administration of sodium chloride 0.9% can cause hyperchloremic metabolic acidosis in a reproducible manner. The elevated chloride concentration in 0.9% NaCl solution can also adversely affect renal perfusion. This effect is thought to be induced by hyperchloremia that causes renal artery vasoconstriction. For these reasons, the use of 0.9% NaCl solution is raising attention and some would advocate the use of a more "physiological" solution, such as balanced solutions that contain a level of chloride closer to that of plasma. Few prospective, randomized, controlled trials are available today and most were done in a perioperative setting. Some studies suggest that the chloride excess in 0.9% NaCl solution could have clinical consequences; however, this remains to be established by quality randomized controlled trials.

Changes in Sonographically Measured Inferior Vena Caval Diameter in Response to Fluid Loading in Term Pregnancy

OBJECTIVES

The purpose of this study was to determine whether the inferior vena caval (IVC) diameter is influenced by intravascular volume changes in pregnancy.

METHODS

A prospective observational study was done on 2 groups of normal term gravidas. In 24 patients, we measured the IVC diameter, blood pressure, and heart rate (HR) before and after a 1-L fluid infusion in preparation for regional anesthesia, after initiation of an epidural block, and within 24 hours postpartum. In a second group of 15 women, we measured the IVC diameter sequentially during a 1-L crystalloid infusion.

RESULTS

In the first group, the mean baseline IVC diameter ± SD at end-inspiration was 1.45 ± 0.32 cm, which was 19% smaller than at end-expiration (1.73 ± 0.31 cm; P= .003). This respiratory cycle variation remained significant at each measurement epoch. The mean caval diameter at end-inspiration increased by 23% after the fluid bolus (P = .012). Hydration was not, however, accompanied by any significant change in the HR, mean arterial pressure, or collapsibility index of the inferior vena cava. With epidural anesthesia, the mean arterial pressure decreased from 88 ± 9 to 80 ± 7 mm Hg (P= .018), but the HR and collapsibility index remained unchanged. Postpartum values were not significantly different from their baseline measurements, except for the mean arterial pressure, which was lower by about 6 mm Hg (P = .042). In the second group, the IVC diameter at end-inspiration increased by 31% after the 1-L infusion, and there was a positive correlation between the volume infused and the IVC diameter (r= 0.67; P< .0001).

CONCLUSIONS

Measurable variations in the IVC diameter occur in response to volume changes in normal term pregnancy and postpartum.

Compliance with management guidelines in patients with suspected dengue

Dengue is an endemic disease in Puerto Rico, with three to nine thousand suspected dengue cases reported yearly. In PR, physicians are required to maintain medical education courses about dengue in order to recertify their medical licenses. The purpose of this study was to describe characteristics of patients admitted to Bella Vista Hospital with suspected dengue and estimate the compliance with guidelines established by the CDC documented in medical records. A total of 197 medical records of patients admitted with diagnosis of suspected dengue during January 1, 2013 through December 31, 2013 were reviewed. The annual distribution of admitted cases showed a higher incidence during the months of June through September, with August having the higher incidence of all. Combined aches and pains were most commonly reported at admission with a prevalence of 82%. In general there was a low prevalence of severe disease as per definition at presentation (DM, clinical fluid accumulation, hepatomegaly, pregnancy and/or renal insufficiency). Overall, compliance with CDC established guidelines were only partially followed. The guideline that was followed more frequently was a daily CBC, with 95% of patients having this as part of their management. Prevalence of administration of isotonic intravenous fluids was 63%, monitoring of vital signs was 48%), and administration of bolus of intravenous fluid was11%. No fatalities were reported during the period.

Fluid management in living donor hepatectomy: Recent issues and perspectives

The importance of the safety of healthy living liver donors is widely recognized during donor hepatectomy which is associated with blood loss, transfusion, and subsequent post-operative morbidity. Although the low central venous pressure (CVP) technique can still be effective, it may not be advantageous concerning the safety of healthy donors undergoing hepatectomy. Emerging evidence suggests that stroke volume variation (SVV), a simple and useful index for fluid responsiveness and preload status in various clinical situations, can be applied as a guide for fluid management to reduce blood loss during living donor hepatectomy. Synthetic colloid solutions are also associated with serious adverse events such as the use of renal replacement therapy and transfusion in critically ill or septic patients. However, it is uncertain whether the intra-operative use of colloid solution is associated with similarly adverse effects in patients undergoing living donor hepatectomy. In this review article we discuss the recent issues regarding the low CVP technique and the high SVV method, i.e., maintaining 10%-20% of SVV, for fluid management in order to reduce blood loss during living donor hepatectomy. In addition, we briefly discuss the effects of intra-operative colloid or crystalloid administration for surgical rather than septic or critically ill patients.

Sodium reduction during cardiopulmonary bypass: Plasma-Lyte 148 versus trial fluid as pump primes

OBJECTIVES

We compared effects on plasma sodium concentrations plus calculated plasma tonicity of two "balanced" crystalloid solutions used as 2 L pump primes during cardiopulmonary bypass (CPB): Plasma-Lyte 148 (sodium concentration, 140 mmol/L; potassium concentration, 5 mmol/L) versus a bicarbonate-balanced fluid (sodium concentration, 140 mmol/L; potassium concentration, 0 mmol/L).

DESIGN, SETTING AND PARTICIPANTS

We analysed pooled data from two prospective interventional studies performed in university-affiliated hospitals, from 50 patients undergoing elective cardiac surgery.

INTERVENTIONS

Participants were allocated equally to Plasma-Lyte 148 or bicarbonate-balanced fluid, with plasma electrolytes measured by direct ion selective electrodes immediately before bypass (pre-CPB), within 3 minutes of commencement (T2), and before bypass cessation (end-CPB).

RESULTS

Plasma sodium fell at T2 in 46 patients (92%) (P<0.0005). With Plasma-Lyte 148, the mean sodium decreased by 3.0 mmol/L (SD, 1.7 mmol/L), and with bicarbonate-balanced fluid it decreased by 2.2 mmol/L (SD, 1.1 mmol/L) (P=0.002). The mean tonicity fell by >5 mOsm/kg for both groups (P<0.0005). At end-CPB, the mean sodium for both groups remained reduced by >2 mmol/L (P<0.0005). In the group receiving Plasma-Lyte 148, 52% of patients were hyponatraemic (sodium<135 mmol/L) at T2 and end-CPB.

CONCLUSIONS

Sodium reductions were common with both priming solutions, but more severe with Plasma-Lyte 148. Crystalloid priming solutions require sodium concentrations>140mmol/L to ensure normonatraemia throughout CPB.

Hemodynamic Consequences of Malignant Ascites in Epithelial Ovarian Cancer Surgery*: A Prospective Substudy of a Randomized Controlled Trial

Malignant ascites (MA) is most commonly observed in patients scheduled for epithelial ovarian cancer (EOC) surgery and is supposed as a major risk factor promoting perioperative hemodynamic deterioration. We aimed to assess the hemodynamic consequences of MA on systemic circulation in patients undergoing cytoreductive EOC surgery.This study is a predefined post-hoc analysis of a randomized controlled pilot trial comparing intravenous solutions within a goal-directed algorithm to optimize hemodynamic therapy in patients undergoing cytoreductive EOC surgery. Ascites was used to stratify the EOC patients prior to randomization in the main study. We analyzed 2 groups according to the amount of ascites (NLAS: none or low ascites [<500 mL] vs HAS: high ascites group [>500 mL]). Differences in hemodynamic variables with respect to time were analyzed using nonparametric analysis for longitudinal data and multivariate generalized estimating equation adjusting the analysis for the randomized study groups of the main study.A total of 31 patients in the NLAS and 16 patients in the HAS group were analyzed. Although cardiac output was not different between groups suggesting a similar circulatory blood flow, the HAS group revealed higher heart rates and lower stroke volumes during surgery. There were no differences in pressure-based hemodynamic variables. In the HAS group, fluid demands, reflected by the time to reindication of a fluid challenge after preload optimization, increased steadily, whereas stroke volume could not be maintained at baseline resulting in hemodynamic instability after 1.5 h of surgery. In contrast, in the NLAS group fluid demands were stable and stroke volume could be maintained during surgery. Clinically relevant associations of the type of fluid replacement with hemodynamic consequences were particularly observed in the HAS group, in which transfusion of fresh frozen plasma (FFP) was associated to an improved circulatory flow and reduced vasopressor and fluid demands, whereas the administration of artificial infusion solutions was related to opposite effects.Malignant ascites >500 mL implies increased fluid demands and substantial alterations in circulatory blood flow during cancer surgery. Fresh frozen plasma transfusion promotes recovering hemodynamic stability in patients with malignant ascites >500 mL, in whom artificial infusion solutions could not prevent from hemodynamic deterioration.

[GOAL-DIRECTED FLUID THERAPY IN SEVERE CONCOMITANT TRAUMA]

METHODS

We examined 78 patients with severe concomitant injury. Were evaluated the severity of the injury and indices of volumetric haemodynamic monitoring by PICCO. The retrospective comparison group consisted of 50 patients with severe concomitant injury who were treated in the ICU of Trauma Institution during 2009-2011.

RESULTS

In patients with severe concomitant injury goal-directed fluid therapy based on PICCO monitoring parameters increasing the volume of infusion on the second and third post-traumatic days by 45% and 24%, respectively (< 0.05). Infusion-related pulmonary complications in the study group patients were not recorded Goal-directed fluid therapy was one of the factors that made it possible to reduce patient's mortality 2.1 times on conditions that severity of the injury and the initial state were similar. Colloid (6% HES 200/0.5) infusion was associated with increases in rate of transient azotemia.

Multidisciplinary consensus document on the management of massive haemorrhage (HEMOMAS document)

Massive haemorrhage is common and often associated with high morbidity and mortality. We perform a systematic review of the literature, with extraction of the recommendations from the existing evidences because of the need for its improvement and the management standardization. From the results we found, we wrote a multidisciplinary consensus document. We begin with the agreement in the definitions of massive haemorrhage and massive transfusion, and we do structured recommendations on their general management (clinical assessment of bleeding, hypothermia management, fluid therapy, hypotensive resuscitation and damage control surgery), blood volume monitoring, blood products transfusion (red blood cells, fresh frozen plasma, platelets and their best transfusion ratio), and administration of hemostatic components (prothrombin complex, fibrinogen, factor VIIa, antifibrinolytic agents).

Effect of a Buffered Crystalloid Solution vs Saline on Acute Kidney Injury Among Patients in the Intensive Care Unit: The SPLIT Randomized Clinical Trial

IMPORTANCE

Saline (0.9% sodium chloride) is the most commonly administered intravenous fluid; however, its use may be associated with acute kidney injury (AKI) and increased mortality.

OBJECTIVE

To determine the effect of a buffered crystalloid compared with saline on renal complications in patients admitted to the intensive care unit (ICU).

DESIGN AND SETTING

Double-blind, cluster randomized, double-crossover trial conducted in 4 ICUs in New Zealand from April 2014 through October 2014. Three ICUs were general medical and surgical ICUs; 1 ICU had a predominance of cardiothoracic and vascular surgical patients.

PARTICIPANTS

All patients admitted to the ICU requiring crystalloid fluid therapy were eligible for inclusion. Patients with established AKI requiring renal replacement therapy (RRT) were excluded. All 2278 eligible patients were enrolled; 1152 of 1162 patients (99.1%) receiving buffered crystalloid and 1110 of 1116 patients (99.5%) receiving saline were analyzed.

INTERVENTIONS

Participating ICUs were assigned a masked study fluid, either saline or a buffered crystalloid, for alternating 7-week treatment blocks. Two ICUs commenced using 1 fluid and the other 2 commenced using the alternative fluid. Two crossovers occurred so that each ICU used each fluid twice over the 28 weeks of the study. The treating clinician determined the rate and frequency of fluid administration.

MAIN OUTCOMES AND MEASURES

The primary outcome was proportion of patients with AKI (defined as a rise in serum creatinine level of at least 2-fold or a serum creatinine level of ≥3.96 mg/dL with an increase of ≥0.5 mg/dL); main secondary outcomes were incidence of RRT use and in-hospital mortality.

RESULTS

In the buffered crystalloid group, 102 of 1067 patients (9.6%) developed AKI within 90 days after enrollment compared with 94 of 1025 patients (9.2%) in the saline group (absolute difference, 0.4% [95% CI, -2.1% to 2.9%]; relative risk [RR], 1.04 [95% CI, 0.80 to 1.36]; P = .77). In the buffered crystalloid group, RRT was used in 38 of 1152 patients (3.3%) compared with 38 of 1110 patients (3.4%) in the saline group (absolute difference, -0.1% [95% CI, -1.6% to 1.4%]; RR, 0.96 [95% CI, 0.62 to 1.50]; P = .91). Overall, 87 of 1152 patients (7.6%) in the buffered crystalloid group and 95 of 1110 patients (8.6%) in the saline group died in the hospital (absolute difference, -1.0% [95% CI, -3.3% to 1.2%]; RR, 0.88 [95% CI, 0.67 to 1.17]; P = .40).

CONCLUSIONS AND RELEVANCE

Among patients receiving crystalloid fluid therapy in the ICU, use of a buffered crystalloid compared with saline did not reduce the risk of AKI. Further large randomized clinical trials are needed to assess efficacy in higher-risk populations and to measure clinical outcomes such as mortality.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: ACTRN12613001370796.