Fluid resuscitation with colloid or crystalloid solutions

Electrolytes, albumin and acid base equilibrium during laparoscopic surgery

BACKGROUND

Surgery, causing inflammation, disrupts endothelial permeability leading to movement of fluids and albumin across the vascular barrier. Fluid therapy for restoring circulatory homeostasis may lead to positive fluid balance which has been shown to increase morbidity and mortality in surgical patients. The current investigation aims to describe physio-pathological changes in circulating albumin, fluid and electrolyte balance, and acidbase equilibrium in a cohort of patients undergoing laparoscopic surgery under general anesthesia.

METHODS

Single-center prospective observational study. Patients undergoing laparoscopic colorectal surgery were screened for eligibility.. Before surgery the baseline fasting conditions were homogenized. Hemoglobin, urinary and plasmatic were collected before surgery and then at pre-defined timepoints. Albumin/Creatinine ratio was measured before and after surgery. Expected and actual circulating Sodium concentrations were compared according to a physiological theoretical model. Assessment and quantification of changes in major electrolytes, albumin and acid-base balance was defined as the primary outcome of the study.

RESULTS

38 patients were enrolled in the protocol. Patients had a positive electrolytes (Na+ 295 [244-375] mmol, Cl- 234 [195-295] mmol, K+ 16.8 [12.0-21.4] mmol) and fluid balance (2165 [1727-2728] ml). The positive fluid balance was associated with stable chloride (105 [103-107], end study vs 103 [102-106] mmol/L, baseline, p=ns) and potassium (4.2 [3.8-4.4], end study vs 4.1 [3.6-4.4] mmol/L, baseline, p=ns) levels, but sodium concentrations decreased over time (138 [137-140], end study vs 139 [138-141] mmol/L, baseline, p<0.05). The Albumin/Creatinine ratio was higher at the end of surgery 134 [61-267] vs 7 [4-14], p<0.001).

CONCLUSIONS

Data from patients undergoing colorectal laparoscopic surgery showed a positive fluid balance, decreased circulating albumin and increased albuminuria. A positive sodium balance was not always associated with an increase in sodium plasma concentration.

Plasma expanders for people with cirrhosis and large ascites treated with abdominal paracentesis

BACKGROUND

Plasma volume expanders are used in connection to paracentesis in people with cirrhosis to prevent reduction of effective plasma volume, which may trigger deleterious effect on haemodynamic balance, and increase morbidity and mortality. Albumin is considered the standard product against which no plasma expansion or other plasma expanders, e.g. other colloids (polygeline , dextrans, hydroxyethyl starch solutions, fresh frozen plasma), intravenous infusion of ascitic fluid, crystalloids, or mannitol have been compared. However, the benefits and harms of these plasma expanders are not fully clear.

OBJECTIVES

To assess the benefits and harms of any plasma volume expanders such as albumin, other colloids (polygeline, dextrans, hydroxyethyl starch solutions, fresh frozen plasma), intravenous infusion of ascitic fluid, crystalloids, or mannitol versus no plasma volume expander or versus another plasma volume expander for paracentesis in people with cirrhosis and large ascites.

SEARCH METHODS

We searched the Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, LILACS, CNKI, VIP, Wanfang, Science Citation Index Expanded, and Conference Proceedings Citation Index until January 2019. Furthermore, we searched FDA, EMA, WHO (last search January 2019), www.clinicaltrials.gov/, and www.controlled-trials.com/ for ongoing trials.

SELECTION CRITERIA

Randomised clinical trials, no matter their design or year of publication, publication status, and language, assessing the use of any type of plasma expander versus placebo, no intervention, or a different plasma expander in connection with paracentesis for ascites in people with cirrhosis. We considered quasi-randomised, retrieved with the searches for randomised clinical trials only, for reports on harms.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. We calculated the risk ratio (RR) or mean difference (MD) using the fixed-effect model and the random-effects model meta-analyses, based on the intention-to-treat principle, whenever possible. If the fixed-effect and random-effects models showed different results, then we made our conclusions based on the analysis with the highest P value (the more conservative result). We assessed risks of bias of the individual trials using predefined bias risk domains. We assessed the certainty of the evidence at an outcome level, using GRADE, and constructed 'Summary of Findings' tables for seven of our review outcomes.

MAIN RESULTS

We identified 27 randomised clinical trials for inclusion in this review (24 published as full-text articles and 3 as abstracts). Five of the trials, with 271 participants, assessed plasma expanders (albumin in four trials and ascitic fluid in one trial) versus no plasma expander. The remaining 22 trials, with 1321 participants, assessed one type of plasma expander, i.e. dextran, hydroxyethyl starch, polygeline, intravenous infusion of ascitic fluid, crystalloids, or mannitol versus another type of plasma expander, i.e. albumin in 20 of these trials and polygeline in one trial. Twenty-five trials provided data for quantitative meta-analysis. According to the Child-Pugh classification, most participants were at an intermediate to advanced stage of liver disease in the absence of hepatocellular carcinoma, recent gastrointestinal bleeding, infections, and hepatic encephalopathy. All trials were assessed as at overall high risk of bias. Ten trials seemed not to have been funded by industry; twelve trials were considered unclear about funding; and five trials were considered funded by industry or a for-profit institution.We found no evidence of a difference in effect between plasma expansion versus no plasma expansion on mortality (RR 0.52, 95% CI 0.06 to 4.83; 248 participants; 4 trials; very low certainty); renal impairment (RR 0.32, 95% CI 0.02 to 5.88; 181 participants; 4 trials; very low certainty); other liver-related complications (RR 1.61, 95% CI 0.79 to 3.27; 248 participants; 4 trials; very low certainty); and non-serious adverse events (RR 1.04, 95% CI 0.32 to 3.40; 158 participants; 3 trials; very low certainty). Two of the trials stated that no serious adverse events occurred while the remaining trials did not report on this outcome. No trial reported data on health-related quality of life.We found no evidence of a difference in effect between experimental plasma expanders versus albumin on mortality (RR 1.03, 95% CI 0.82 to 1.30; 1014 participants; 14 trials; very low certainty); serious adverse events (RR 0.89, 95% CI 0.10 to 8.30; 118 participants; 2 trials; very low certainty); renal impairment (RR 1.17, 95% CI 0.71 to 1.91; 1107 participants; 17 trials; very low certainty); other liver-related complications (RR 1.10, 95% CI 0.82 to 1.48; 1083 participants; 16 trials; very low certainty); and non-serious adverse events (RR 1.37, 95% CI 0.66 to 2.85; 977 participants; 14 trials; very low certainty). We found no data on heath-related quality of life and refractory ascites.

AUTHORS' CONCLUSIONS

Our systematic review and meta-analysis did not find any benefits or harms of plasma expanders versus no plasma expander or of one plasma expander such as polygeline, dextrans, hydroxyethyl starch, intravenous infusion of ascitic fluid, crystalloids, or mannitol versus albumin on primary or secondary outcomes. The data originated from few, small, mostly short-term trials at high risks of systematic errors (bias) and high risks of random errors (play of chance). GRADE assessments concluded that the evidence was of very low certainty. Therefore, we can neither demonstrate or discard any benefit of plasma expansion versus no plasma expansion, and differences between one plasma expander versus another plasma expander.Larger trials at low risks of bias are needed to assess the role of plasma expanders in connection with paracentesis. Such trials should be conducted according to the SPIRIT guidelines and reported according to the CONSORT guidelines.

Fluid resuscitation in pre-hospital trauma care: a consensus view

Fluid administration for trauma in the pre-hospital environment is a challenging and controversial area. The available evidence does not clearly support any single approach. Nevertheless, some provisional conclusions may be drawn. We believe that the following guidelines represent a sound expert consensus. It is intended that they will be modifi ed as future research brings clarity to the area. When treating trauma victims in the pre-hospital arena cannulation should take place en route where possible. Only two attempts at cannulation should be made. Transfer should not be delayed by attempts to obtain intravenous access. Entrapped patients require cannulation at the scene. Normal saline may be titrated in boluses of 250 ml against the presence or absence of a radial pulse (caveats; penetrating torso injury, head injury, infants).

Hydroxyethylstarch supplementation in burn resuscitation--a prospective randomised controlled trial

INTRODUCTION

Hydroxyethylstarches (HES) are thought to be beneficial in trauma and major surgery management, due to their volume expansion and anti-inflammatory properties. This study examined the use of 6% (HES) in burn resuscitation.

METHODS

26 adult patients with burns exceeding 15% total body surface area (TBSA) were randomised to either crystalloid (Hartmann's solution) or a colloid-supplemented resuscitation regime, where 1/3 of the crystalloid-predicted requirement was replaced by 6% HES.

RESULTS

There was no difference in age, gender or TBSA between the two groups. The median (95% CI) fluid volume/%TBSA received in the first 24 h was 307 ml and 263 ml for the crystalloid only and HES-supplemented group respectively (p=0.0234, Mann-Whitney). Body weight gain within the first 24 h after injury was significantly lower in the HES-supplemented group 2.5 kg versus 1.4 kg respectively (p=0.0039). The median (95% CI) serum C-reactive protein at 48 h after injury was 210 (167-257) and 128 (74-145) mg/L for the crystalloid only and HES-supplemented group respectively (p=0.0001). Albumin-creatinine ratio per % burn (ACR, a marker of capillary leak) was lower in the HES-supplemented group at 12h after burn (p=0.0310).

CONCLUSIONS

Patients treated with HES-supplemented resuscitation required less fluid, showed less interstitial oedema and a dampened inflammatory response compared to patients receiving isotonic crystalloid alone.

Sugar Solutions Used In Resuscitation

Although recent studies have shown that the timing of volume replacement deserves careful consideration (56), which fluid to use is less clear, with the perennial debate of crystalloid v colloid and now colloid v colloid still unresolved. This review has examined three sugar solutions, two colloids and one crystalloid. In general, all three agents are unhelpful in the immediate resuscitation of hypovolaemic trauma by virtue of a combination of pathophysiology and side effects. Dextran solutions and mannitol are useful in specific situations.

The Thoracic Surgical Patient: Initial Postoperative Care

Thoracic surgery patients require complex perioperative care. Accurate preoperative screening of pulmonary conditions can only partially predict the requirement of postoperative mechanical ventilation. In general, extensive lung resections are associated with significant gas exchange abnormalities. In this group of patients, a mechanical ventilation strategy protective from barotrauma and volutrauma and a conservative use of intraoperative and postoperative fluid limit the inevitable increase of extravascular lung water and gas exchange impairment. A wise use of pulmonary vasodilatatory and bronchodilating drugs and airway manipulation including suctioning and bronchoscopy can also significantly affect postoperative respiratory dysfunction and hospital stay. A number of acute postoperative complications have been described specifically related to the type of surgery or pleural space suctioning devices. The role of the intensivist is to maintain a low index of suspicion for such complications, when acute hemodynamic or pulmonary deterioration occurs and be prepared to immediately correct them or alert the thoracic surgeon. In general, when these roles are observed, thoracic surgery can be safely performed with a low perioperative mortality.

Randomized trial of hydroxyethyl starch versus gelatine for trauma resuscitation

BACKGROUND

Previous studies have demonstrated the rapid increase in systemic capillary permeability after blunt trauma and its association with poor outcome. There are theoretical advantages in resuscitation with colloid fluids, which are well retained in the vascular compartment during times of capillary leak. The aim of this study was to compare the effects of posttrauma resuscitation with hydroxyethyl starch (HES) (molecular mass, 250 kDa) or gelatine (molecular mass, 30 kDa), the hypothesis being that HES would reduce capillary leak.

METHODS

Forty-five patients suffering blunt trauma were randomized on admission to receive either gelatine (Gelofusine) (n = 21) or HES (Pentaspan) (n = 24) for the first 24 hours, after which the choice of fluid was at the discretion of the clinician. The mean Injury Severity Score for the HES and gelatine groups were 20.0 (range, 9-41) and 18.1 (range, 9-32), respectively (p = 0.43). Capillary permeability was assessed by urine albumin excretion rate for the first 24 hours. For 5 days the daily mean P(O2)/F(IO2) ratio, serum C-reactive protein, hemoglobin, white cell and platelet counts, prothrombin, and activated partial thromboplastin time were recorded.

RESULTS

Capillary permeability was lower in HES-treated patients during the first 24 hours. Log mean (95% confidence interval) albumin excretion rate for gelatine and HES groups at 6 hours were 117.5 (84.9) and 46.8 (24.3) microg/min (p = 0.011), at 12 hours were 54.9 (30.0) and 17.2 (7.6) microg/min (p = 0.001), and at 24 hours were 50.5 (23.4) and 23.6 (16.3) microg/min (p = 0.030), respectively. The mean (95% confidence interval) P(O2)/F(IO2) ratio for the HES and gelatine groups 48 hours after admission were 324 (44) and 267 (43) mm Hg, respectively (p = 0.03). The mean (95% confidence interval) serum C-reactive protein in the HES and gelatine groups 24 hours after admission were 72.4 (19.2) and 105.7 (30.1) mg/L, respectively (p = 0.03). There were no significant differences in any of the hematologic parameters during the first 48 hours.

CONCLUSION

The results suggest that compared with gelatine, resuscitation with HES reduces posttrauma capillary leak.