Contribution of blood detection of insulin-like growth factor binding protein-1 for the diagnosis of amniotic-fluid embolism: a retrospective multicentre cohort study.

OBJECTIVE: To assess the contribution of maternal blood detection of IGFBP-1 for the diagnosis of amniotic-fluid embolism in clinical daily practice. DESIGN: A retrospective multicentre cohort study. SETTING: Three tertiary care obstetric units in France. SAMPLE: Data of 86 women for whom amniotic-fluid embolism had been suspected and maternal serum detection of IGFBP-1 had been performed between 2011 and 2019 were analysed. METHODS: The criteria defined by the United Kingdom Obstetric Surveillance System (UKOSS) were used for the retrospective diagnosis of amniotic-fluid embolism. The more structured definition proposed by the Society for Maternal-Fetal Medicine and the Amniotic Fluid Embolism Foundation (SMFM) was also used as secondary endpoint. MAIN OUTCOME MEASURES: Agreements between biological and clinical assessments were tested. The performance of blood detection of IGFBP-1 for the diagnosis of amniotic-fluid embolism according to the UKOSS criteria, and to the SMFM definition, was also assessed. RESULTS: There was only slight agreement between clinical and laboratory diagnosis of amniotic-fluid embolism (Cohen's Kappa coefficient: 0.04). Blood detection of IGFBP-1 had a sensitivity of 16%, a specificity of 88%, a positive and a negative likelihood ratio of 1.3 and 0.95, respectively, and a positive and a negative predictive value of 58 and 50%, respectively, for the diagnosis of amniotic-fluid embolism based on the UKOSS criteria. The use of the more structured SMFM definition of amniotic-fluid embolism did not substantially change the results. CONCLUSION: These results question the usefulness of blood detection of IGFBP-1 for the early diagnosis of amniotic-fluid embolism in daily clinical practice. TWEETABLE ABSTRACT: This retrospective multicentre study questions the contribution of IGFBP-1 detection for the diagnosis of AFE.

Reliability of gastric suctioning compared with ultrasound assessment of residual gastric volume: a prospective multicentre cohort study.

We aimed to compare the reliability of aspiration via a nasogastric tube with ultrasound for assessment of residual gastric volume. Sixty-one adult patients who were mechanically ventilated and received continuous enteral feeding through a nasogastric tube for > 48 h were included. A first qualitative and quantitative ultrasound examination of the gastric antrum was followed by gastric suctioning, performed by an operator blinded to the result of the ultrasound examination. A second ultrasound examination was performed thereafter, followed by re-injection of the aspirated gastric contents (≤ 250 ml) into the stomach. A third ultrasound assessment was then immediately performed. If the suctioned volume was ≥ 250 ml, 250 mg erythromycin was infused over 30 min. A fourth ultrasound was performed 90 min after the third. Sixty (98%) patients had a qualitatively assessed full stomach at first ultrasound examination vs. 52 (85%) after gastric suctioning (p = 0.016). The calculated gastric volume significantly decreased after gastric suctioning, without a significant decrease in the number of patients with volume ≥ 250 ml. Four of the nine patients with calculated gastric volume ≥ 250 ml had vomiting within the last 24 h (p = 0.013). The antral cross-sectional area significantly decreased between the third and the fourth ultrasound examination (p = 0.015). Erythromycin infusion did not make a significant difference to gastric volume (n = 10). Our results demonstrate that gastric suctioning is not a reliable tool for monitoring residual gastric volume. Gastric ultrasound is a feasible and promising tool for gastric volume monitoring in clinical practice.

Effect of body position on qualitative and quantitative ultrasound assessment of gastric fluid contents.

We assessed the impact of raising the upper section of the bed, and patient positioning, on ultrasound assessment of gastric fluid contents. We performed ultrasound examinations in 25 subjects lying on their back, left and right sides at bed angles of 0°, 30°, 45° and 90°; this was carried out while the subjects were fasted, and repeated 10 min after drinking ≥ 50 ml water. After drinking, gastric contents were detected more frequently in the 45° semirecumbent position compared with the supine and 30° positions. The diagnostic performance of the Perlas qualitative grading scale to detect gastric fluid volume > 1.5 ml.kg-1 was improved at 45°, compared with 0° and 30° angles. The use of a composite ultrasound grading scale at a 45° angle was associated with the best performance, with a sensitivity and specificity of 82%. Antral cross-sectional area was significantly increased when measured in the right lateral position, but there was no effect of raising the bed. In conclusion, raising the upper section of the bed significantly affected qualitative assessment of gastric fluid contents. Further studies are required to determine the most appropriate composite ultrasound grading scale and bed angle for fast and reliable qualitative ultrasound detection of fluid volumes > 1.5 ml.kg-1 .

Incidence, characteristics, and predictive factors for medication errors in paediatric anaesthesia: a prospective incident monitoring study.

BACKGROUND: Medication errors are not uncommon in hospitalized patients. Paediatric patients may have increased risk for medication errors related to complexity of weight-based dosing calculations or problems with drug preparation and dilution. This study aimed to determine the incidence of medication errors in paediatric anaesthesia in a university paediatric hospital, and to identify their characteristics and potential predictive factors. METHODS: This prospective incident monitoring study was conducted between November 2015 and January 2016 in an exclusively paediatric surgical centre. Children <18 yr undergoing general anaesthesia were consecutively included. For each procedure, an incident form was completed by the attending anaesthetist on an anonymous and voluntary basis. RESULTS: Incident forms were completed in 1400 (73%) of the 1925 general anaesthetics performed during the study period with 37 reporting at least one medication error (2.6%). Drugs most commonly involved in medication errors were opioids and antibiotics. Incorrect dose was the most frequently reported type of error (n=27, 67.5%), with dilution error involved in 7/27 (26%) cases of incorrect dose. Duration of procedure >120 min was the only factor independently associated with medication error [adjusted odds ratio: 4 (95% confidence interval: 2-8); P=0.0001]. CONCLUSIONS: Medication errors are not uncommon in paediatric anaesthesia. Identification of the mechanisms related to medication errors might allow preventive measures that can be assessed in further studies.

Assessment of Neurological Toxicity of Hydroxyethyl Starch 130/0.4 Injected in the Intrathecal Space in Rats.

Objective: Epidural blood patch is the procedure of choice to relieve postdural puncture headache. Hydroxyethyl-starch (HES) has been proposed as a patch in some circumstances such as in the case of hematological disease due to the theoretical risk of neoplastic seeding to the central nervous system. Acute neurological HES toxicity has been excluded by a previous animal study, but the long-term neurological toxicity has not been evaluated. Methods: Rats were randomly assigned to one of three groups: no intrathecal injection, 20 µL of intrathecal saline, or a 20-µL intrathecal HES (6% hydroxyethyl starch 130/0.4) administered via a cervical puncture. Clinical daily rat activity was measured before and after dural puncture by actinometry. The rats were killed at day 28, and the spinal cord was surgically removed and stained with hematoxylin-phloxine-saffron for gross and microscopic examination. Results: Eleven rats underwent dural puncture without injection, 11 were injected with normal saline, and 12 received intrathecal HES. No clinical or actimetric changes (total distance traveled, number of direction changes, and number of rearings) were observed up to one month after injection. Nonspecific histopathological changes were equally observed in all groups. Conclusions: The results of the current study indicate that intrathecal injection of HES in rats does not induce any clinical or histopathological evidence of long-term neuronal toxicity. Further safety studies in animals are warranted before HES might be considered a safe alternative to the classic epidural blood patch.

The effect of pre-operative gastric ultrasound examination on the choice of general anaesthetic induction technique for non-elective paediatric surgery. A prospective cohort study.

Ultrasound examination of the gastric antrum is a non-invasive tool that allows reliable estimation of gastric contents. We performed this prospective cohort study in non-elective paediatric surgery to assess whether gastric ultrasound may help to determine the best anaesthetic induction technique, whether rapid sequence or routine. The primary outcome was the reduction of inappropriate induction technique. A pre-operative clinical assessment was performed by the attending anaesthetist who made a provisional plan for induction. Gastric ultrasound was performed in the semirecumbent and right lateral decubitus positions for a qualitative assessment of gastric contents, using a 0-2 grading scale. A final induction plan was made based on this assessment. Immediately after tracheal intubation, gastric contents were suctioned through a multi-orifice nasogastric tube; these were defined as above risk threshold for regurgitation and aspiration if there was clear fluid > 0.8 ml.kg-1 , and/or the presence of thick fluid and/or solid particles. Gastric ultrasound was feasible in 130 out of 143 (90%) of children, and led to a change in the planned induction technique in 67 patients: 30 from routine to rapid sequence, and 37 from rapid sequence to routine. An appropriate induction technique was therefore performed in 85% of children, vs. 49% planned after pre-operative clinical assessment alone (p < 0.00001). Our results suggest that gastric ultrasound is a useful guide to the general anaesthetic induction technique with respect to the risk of pulmonary aspiration, in comparison with pre-operative clinical assessment alone.

Effect of gum chewing on gastric volume and emptying: a prospective randomized crossover study.

BACKGROUND: Current fasting guidelines allow oral intake of water up to 2 h before induction of anaesthesia. We assessed whether gum chewing affects gastric emptying of 250 ml water and residual gastric fluid volume measured 2 h after ingestion of water. METHODS: This prospective randomized observer-blind crossover trial was performed on 20 healthy volunteers who attended two separate study sessions: Control and Chewing gum (chlorophyll flavour, with 2.1 g carbohydrate). Each session started with an ultrasound measurement of the antral area, followed by drinking 250 ml water. Then, volunteers either chewed a sugared gum for 45 min (Chewing gum) or did not (Control). Serial measurements of the antral area were performed during 120 min, and the half-time to gastric emptying (t½), total gastric emptying time, and gastric fluid volume before ingestion of water and 120 min later were calculated. RESULTS: Gastric emptying of water was not different between sessions; the mean (sdsd) t½ was 23 (10) min in the Control session and 21 (7) min in the Chewing gum session (P=0.52). There was no significant difference between sessions in gastric fluid volumes measured before ingestion of water and 120 min later. CONCLUSIONS: Chewing gum does not affect gastric emptying of water and does not change gastric fluid volume measured 2 h after ingestion of water. CLINICAL TRIAL REGISTRATION: NCT02673307.

Prevalence and factors predictive of full stomach in elective and emergency surgical patients: a prospective cohort study.

Background: This prospective observational study sought to assess the rate of full and empty stomach in elective and emergency patients and to determine the factors associated with full stomach. Methods: Non-premedicated patients were consecutively included between May 2014 and October 2014. Ultrasound examination of the gastric antrum was performed by an operator blinded to the history of the patient. It included measurement of the antral cross-sectional area, performed in the supine position with the head of the bed elevated to 45°, and qualitative assessment of the gastric antrum, performed in both semirecumbent and right lateral decubitus positions. Full stomach was defined by the appearance of any gastric content in both positions (Grade 2). Empty stomach was defined either by empty antrum in both positions (Grade 0) or by empty antrum in the semirecumbent position only (Grade 1) with measured antral area <340 mm2. The combination of Grade 1 and antral area >340 mm2 defined intermediate stomach. Logistic regression analyses were performed for the identification of factors associated with full stomach. Results: Four hundred and forty patients were analysed. The prevalence of full stomach was 5% (95% confidence interval: 2­9) in elective patients and 56% (95% confidence interval: 50­62) in emergency patients (P<0.0001). Obesity, diabetes mellitus, emergency surgery, and preoperative consumption of opiates were independent factors predictive of full stomach. Conclusions: The results suggest that preoperative ultrasound assessment of gastric content should be performed in all emergency patients, and in elective patients with identified predictive factors for full stomach.

Children and parental anxiolysis in paediatric ambulatory surgery: a randomized controlled study comparing 0.3 mg kg-1 midazolam to tablet computer based interactive distraction.

BACKGROUND: The operating theatre, anaesthesia induction and separation from parents create fear and anxiety in children. Anxiety leads to adverse behavioral changes appearing and sometimes persisting during the postoperative period. Our aim was to compare the effects of midazolam (0.3 mg kg-1: MDZ) for premedication with age-appropriate tablet game apps (TAB) on children anxiety during and after ambulatory surgery. METHODS: A randomized controlled trial was conducted from May 16th, 2013 to March 25th, 2014 at the Children Hospital of Lyon. The primary outcome of this study was the change in m-YPAS score at the time of anaesthetic mask induction. Anxiety was also assessed in the waiting surgical area, at the time of separation with parents and when back in the ambulatory surgery ward. RESULTS: One hundred and eighteen patients aged four-11 yr were recruited, 60 in the TAB Group and 58 in the MDZ Group. Main endpoint was missing for three patients from the MDZ Group. At the time of mask induction, there was no significant difference between MDZ and TAB Group for the m-YPAS score (40.5 (18.6) vs 41.8 (20.7), P = 0.99). There was no significant correlation between m-YPAS score and its evolution over the four period of time between subjects. CONCLUSIONS: We were not able to show whether TAB is superior to MDZ to blunt anxiety in children undergoing ambulatory surgery. TAB is a non-pharmacological tool which has the capacity in reducing perioperative stress without any sedative effect in this population. CLINICAL TRIAL REGISTRATION: NCT 02192710.

Ultrasound assessment of gastric contents in children undergoing elective ear, nose and throat surgery: a prospective cohort study.

Ultrasound examination of the gastric antrum allows reliable assessment of gastric contents and volume. Postoperative assessment of gastric contents before recovery from anaesthesia could help the physician to choose the most appropriate extubation technique after surgery in children. In this prospective observational study, we assessed whether significant changes occurred in gastric contents during the intra-operative period in children undergoing elective ear, nose and throat (ENT) surgery. Children aged between six months and 16 years were recruited consecutively. Ultrasound examination of the antrum was performed before induction of anaesthesia and at the end of surgery before tracheal extubation, and included quantitative and qualitative assessment of gastric contents. The mean (SD) gastric volume was 0.28 (0.30) ml.kg-1 before surgery and 0.27 (0.30) ml.kg-1 after surgery, p = 0.82. No solid contents were identified in the antrum, and the gastric volume was < 1.5 ml.kg-1 in all patients during both ultrasound examinations. Our results suggest that, after elective ENT surgery, children are not at risk of a full stomach before tracheal extubation, and that pulmonary aspiration of blood that may occur after elective ENT surgery is probably not related to regurgitation of ingested blood from the stomach.

Ultrasound assessment of the gastric contents for the guidance of the anaesthetic strategy in infants with hypertrophic pyloric stenosis: a prospective cohort study.

BACKGROUND: Evacuation of gastric content through a nasogastric tube, followed by rapid sequence induction, is usually recommended in infants undergoing pyloromyotomy. However, rapid sequence induction may be challenging, and is therefore controversial. Some anaesthetists regularly perform classical non-rapid induction technique, after blind aspiration of the gastric contents, although this aspiration may have been incomplete. This prospective observational study aimed to assess whether the ultrasound monitoring of the aspiration of the stomach contents, may be useful to appropriately guide the choice of the anaesthetic induction technique, in infants undergoing pyloromyotomy. METHODS: Infants undergoing pyloromyotomy were consecutively included. Ultrasound assessment of the antrum was performed before and after the aspiration of the gastric contents through a 10 French gastric tube. The stomach was defined as empty when no content was seen in both supine and right lateral positions. The correlation between antral area and the aspirated gastric volume was also tested. RESULTS: We analysed 34 infants. Ultrasound examination of the antrum failed in three infants. The stomach was empty in 30/34 infants (nine before aspiration, 21 after aspiration), allowing to perform a non-rapid induction technique in 88.2% of the infants. There was a significant correlation between antral area measured in right lateral decubitus and the aspirated gastric volume. CONCLUSIONS: Our results suggest that the qualitative ultrasound assessment of the antral content may be a simple and useful point-of-care tool, for the choice of the most appropriate anaesthetic technique for pyloromyotomy according to the estimated risk of pulmonary aspiration of gastric contents.

Introduction of a paediatric anaesthesia comic information leaflet reduced preoperative anxiety in children.

BACKGROUND: The aim of the study was to determine whether the introduction of a paediatric anaesthesia comic information leaflet reduced preoperative anxiety levels of children undergoing major surgery. Secondary objectives were to determine whether the level of understanding of participants and other risk factors influence STAIC-S (State-Trait Anxiety Inventory for Children-State subscale) score in children. METHODS: We performed a randomized controlled parallel-group trial comparing preoperative anxiety between two groups of children aged >6 and <17 yr. Before surgery, the intervention group received a comic information leaflet at home in addition to routine information given by the anaesthetist at least 1 day before surgery. The control group received the routine information only. The outcome measure was the difference between STAIC-S scores measured before any intervention and after the anaesthetist's visit. A multiple regression analysis was performed to explore the influence of the level of education, the anxiety of parents, and the childrens' intelligence quotient on STAIC-S scores. RESULTS: One hundred and fifteen children were randomized between April 2009 and April 2013. An intention-to-treat analysis on data from 111 patients showed a significant reduction (P=0.002) in STAIC-S in the intervention group (n=54, mean=-2.2) compared with the control group (n=57, mean=0.90). The multiple regression analysis did not show any influence on STAIC-S scores of the level of education, parental anxiety, or the intelligence quotient of the children. CONCLUSIONS: A paediatric anaesthesia comic information leaflet was a cheap and effective means of reducing preoperative anxiety, measured by STAIC-S, in children. CLINICAL TRIALS REGISTRATION: NCT 00841022.

Ultrasonographic measurement of antral area for estimating gastric fluid volume in parturients.

BACKGROUND: The aim of this prospective observational study was to assess the performance of ultrasonographic gastric antral area (GAA) to predict gastric fluid volumes of >0.4, >0.8 and >1.5 ml kg(-1), in fasted women in established labour. METHODS: A first ultrasound examination of the antrum was performed, in order to confirm gastric vacuity by using a qualitative score. Baselines GAA measurements were obtained in both supine and right lateral decubitus positions. Thereafter, parturients were allowed to drink clear fluids only. Measurement of GAA was repeated 15 min after last fluid intake, in both supine and right lateral positions. Receiver operating characteristics (ROC) curves were constructed to determine the accuracy of GAA to diagnose ingested volumes of >0.4, >0.8 and >1.5 ml kg(-1). RESULTS: Data from forty parturients were analysed. The areas under the ROC curves ranged from 80% to 86%. The cut-off value for antral area measured in supine position, to detect a volume >0.4 ml kg(-1), was 387 mm(2), with a sensitivity of 87%, a specificity of 70% and a negative predictive value of 85%. A cut-off value of 608 mm(2) predicted a fluid volume >1.5 ml kg(-1), with a specificity of 94%, a sensitivity of 75% and a negative predictive value of 92%. CONCLUSIONS: This study provides cut-off values for GAA that could be used in addition to the qualitative assessment of the antrum to define a full stomach in labouring patients.

Changes in qualitative and quantitative ultrasound assessment of the gastric antrum before and after elective caesarean section in term pregnant women: a prospective cohort study.

Ultrasound measurement of the antral cross-sectional area allows a quantitative estimate of gastric contents in non-pregnant adults, but this relationship may be affected by compression of the stomach exerted by the gravid uterus during pregnancy. This study aimed to assess differences in quantitative (Perlas score) and qualitative (antral cross-sectional area) ultrasound assessments of the gastric antrum performed immediately before and after caesarean section. Forty-three women having elective caesarean section performed under spinal anaesthesia were studied in the semirecumbent and semirecumbent-right lateral positions. Thirty-nine women showed no change in stomach contents using the Perlas score between the two measurement periods; four women showed a change, but by one grade only. The median (IQR [range]) antral cross-sectional area was 323 (243-495 [103-908]) mm2 before, and 237 (165-377 [112-762]) mm2 after, caesarean section in the semirecumbent position (p = 0.001); the comparable values in the semirecumbent-right lateral position were 418 (310-640 [161-1238]) mm2 and 362 (280-491 [137-1231]) mm2 (p = 0.09). The distance between the skin and the antrum, and the aorta and the antrum, decreased significantly in both positions after surgery. We suggest that our results indicate that stomach contents remain largely unchanged in women having elective caesarean section, but antral cross-sectional area decreases, especially in the semirecumbent position, related to a change in the position of the stomach within the abdomen. This implies that the relationship of antral cross-sectional area to volume of stomach contents, which has been determined for non-pregnant subjects, may not apply in term pregnant women.

Effect of acute cigarette smoking on gastric contents in regular smoker volunteers. A prospective randomized cross-over study.

BACKGROUND: The authors sought to assess the effect of acute smoking on gastric contents in regular smoker volunteers. The primary endpoint was the variation in antral area during the 120-min study period after cigarette smoking. METHODS: Regular smoker volunteers were included in this prospective randomized single blind cross-over study. Volunteers attended two separate study sessions: Control and Smoking sessions. The study started with an initial ultrasound measurement of the antral area, immediately followed by a 30-min periods of waiting (Control session) or of two-cigarettes smoking (Smoking session). Ultrasound measurements of the antral area were then performed 30, 60, 90 and 120 min after the initial ultrasonography, allowing for the calculations of the variation rates in antral area during the periods 0-30, 0-60, 0-90 and 0-120 min in both sessions. RESULTS: The variation in antral area during the period 0-120 min was equivalent in both sessions, as the difference in the variation rates between both sessions was -1.2%, with 90% confidence interval of the difference including 0 and lying entirely within the range of equivalence of -10% to 10%. No equivalence was found for the periods 0-30, 0-60 and 0-90 min, because of a non-significant decrease in antral area in the Smoking sessions during these periods. CONCLUSIONS: Preoperative acute smoking did not affect the variation in the gastric volume in regular smoker volunteers during the study period. These results allow for the suggestion that acute preoperative smoking does not probably change the risk of pulmonary aspiration of gastric contents in healthy regular smokers. CLINICAL TRIAL REGISTRATION: NCT 02080598.

Neurotoxicity of intrathecal 6% hydroxyethyl starch 130/0.4 injection in a rat model.

Epidural blood patch is the gold standard treatment for post-dural puncture headache, although hydroxyethyl starch may be a useful alternative to blood if the latter is contraindicated. The aim of this experimental study was to assess whether hydroxyethyl starch given via an indwelling intrathecal catheter resulted in clinical or histopathological changes suggestive of neurotoxicity. The study was conducted in rats that were randomly allocated to receive three 10-µl injections on consecutive days of either saline or hydroxyethyl starch administered via the intrathecal catheter. Eight rats were given injections of saline 0.9% and 11 were given 6% hydroxyethyl starch 130/0.4 derived from thin boiling waxy corn starch in 0.9% sodium chloride (Voluven). Daily clinical evaluation, activity measured by actimetry and neuropathological analysis of the spinal cord were subsequently performed to assess for signs of neurotoxicity. No clinical or actimetric changes were observed in either group following intrathecal saline or hydroxyethyl starch administration. Histopathological examination showed non-specific changes with no differences between the two groups. This experimental study in the rat suggests that repeated intrathecal injection of hydroxyethyl starch is not associated with neurotoxicity.

Resuscitation with lipid, epinephrine, or both in levobupivacaine-induced cardiac toxicity in newborn piglets.

BACKGROUND: The optimal dosing regimens of lipid emulsion, epinephrine, or both are not yet determined in neonates in cases of local anaesthetic systemic toxicity (LAST). METHODS: Newborn piglets received levobupivacaine until cardiovascular collapse occurred. Standard cardiopulmonary resuscitation was started and electrocardiogram (ECG) was monitored for ventricular tachycardia, fibrillation, or QRS prolongation. Piglets were then randomly allocated to four groups: control (saline), Intralipid(®) alone, epinephrine alone, or a combination of Intralipd plus epinephrine. Resuscitation continued for 30 min or until there was a return of spontaneous circulation (ROSC) accompanied by a mean arterial pressure at or superior to the baseline pressure and normal sinus rhythm for a period of 30 min. RESULTS: ROSC was achieved in only one of the control piglets compared with most of the treated piglets. Mortality was not significantly different between the three treatment groups, but was significantly lower in all the treatment groups compared with control. The number of ECG abnormalities was zero in the Intralipid only group, but 14 and 17, respectively, in the epinephrine and epinephrine plus lipid groups (P<0.05). CONCLUSIONS: Lipid emulsion with or without epinephrine, or epinephrine alone were equally effective in achieving a return to spontaneous circulation in this model of LAST. Epinephrine alone or in combination with lipid was associated with an increased number of ECG abnormalities compared with lipid emulsion alone.

6% Hydroxyethyl starch (130/0.4) vs Ringer's lactate preloading before spinal anaesthesia for Caesarean delivery: the randomized, double-blind, multicentre CAESAR trial.

BACKGROUND: Vasopressor administration is recommended to prevent hypotension during spinal anaesthesia (SA) for elective Caesarean delivery. We aimed to test the superior efficacy and ensure safety of a hydroxyethyl starch (HES) vs a Ringer's lactate (RL) preloading, when combined with a phenylephrine-based prophylaxis. METHODS: A total of 167 healthy parturients undergoing elective Caesarean delivery under SA were included in this multicentre, randomized, double-blind study. Patients received 500 ml of 6% HES (130/0.4)+500 ml of RL (HES group) or 1000 ml of RL (RL group) i.v. before SA. After SA, i.v. phenylephrine boluses were titrated when systolic arterial pressure (SAP) was below 95% of baseline. The primary outcome was the incidence of maternal hypotension (SAP <80% of baseline). RESULTS: The incidence of both hypotension and symptomatic hypotension (i.e. with dizziness, nausea/vomiting, or both) was significantly lower in the HES group vs the RL group: 36.6% vs 55.3% (one-sided P=0.025) and 3.7% vs 14.1%. There was no significant difference in total phenylephrine requirements [median (range): 350 (50-1800) vs 350 (50-1250) µg]. The decrease in maternal haemoglobin value the day after surgery was similar in the two groups [1.2 (1.0) vs 1.0 (0.9) g dl(-1)]. There was no detectable placental transfer of HES in six umbilical cord blood samples analysed in the HES group. Neonatal outcomes were comparable between the groups. CONCLUSIONS: Compared with a pure RL preloading, a mixed HES-RL preloading significantly improved prevention of both hypotension and symptomatic hypotension based on early phenylephrine bolus administration and did not induce adverse effects. CLINICAL TRIAL REGISTRATION: NCT00694343 (http://clinicaltrials.gov).