Esophageal Doppler Research Articles

The presence of elastic compression stockings reduces the fluid responsiveness of patients in the operating room.

The aim of this study was to investigate whether elastic compression stockings (ECS) can affect fluid responsiveness parameters before and during passive leg raising (PLR) maneuvers. In the operating room (OR), we performed a prospective study including patients referred for cardiac surgery. Blood pressure (BP), ΔPP, heart rate (HR), central venous pressure (CVP), stroke volume (SV) and aortic blood flow (ABF) (by esophageal doppler) were measured according to four conditions: supine position without ECS (baseline 1), lower limbs raised to an angle of 45° (PLR 1), returned to the supine position with ECS (baseline 2), then a second PLR maneuver with ECS was performed (PLR 2). Twenty patients were included. BP, SV, ABF and CVP increased significantly. ΔPP and HR decreased during PLR 1. At baseline 2, HR and ΔPP decreased significantly compared to baseline 1. During PLR 2, increase of SV (4% [9]) and ABF (4% [9]), and the decrease of ΔPP (-19% [104]) were significantly lower than those observed at PLR 1 (7% [21] P=0.05; 9% [8] P=0.02 and -66% [40] P=0.02, respectively). Eleven patients presented a ΔPP≥13% at baseline 1. Only 1 patient still presented a ΔPP≥13% with ECS at baseline 2. Only 3/9 patients with an increase of ABF ≥10% and 2/11 patients with an increase of PP ≥12% during the PLR 1 presented similar results during PLR 2. In the OR, ECS provoke a self-fluid loading increasing ABF, decreasing ΔPP and PLR response. The presence of ECS should be considered when managing hemodynamic parameters of patients.

Multi-parametric functional hemodynamic optimization improves postsurgical outcome after intermediate risk open gastrointestinal surgery: a randomized controlled trial.

Perioperative goal directed therapy (pGDT) using flow monitoring has been associated with improved outcomes. However, its protocols are often based on stroke volume only: as a target for fluid loading, inotropic support and vasopressors (via mathematical coupling of systemic vascular resistance). In this trial, we have tested the multi-parametric pGDT protocol based on esophageal Doppler variables (corrected flow time, peak velocity) in intermediate-to-high risk patients undergoing gastrointestinal surgery. Intermediate-to-high risk patients undergoing gastrointestinal surgery were randomized to standard care (control) or multi-parametric pGDT (intervention). Postoperative complications and death rate as well as hospital length of stay were assessed as primary and secondary outcomes. Overall, 140 patients (intervention, N.=71, and control, N.=69) were included and randomized out of 197 eligible. Higher vasoactive/inotropic drug use and lower fluid balance were observed in the intervention group leading to favorable hemodynamic profile. The pGDT intervention was associated with improved primary outcome (28 days mortality and morbidity defined as occurrence of any defined complication) - 20 patients (28.2%) versus 32 (46.4%) in the control group (P=0.036); RR 0.61 (95% CI: 0.39-0.95), P=0.03. No differences in mortality and hospital length of stay were observed between groups. In this monocentric trial the multi-parametric pGDT protocol based on domain specific functional hemodynamic parameters was associated with lower rate of postoperative complications in intermediate-to-high risk patients undergoing scheduled gastrointestinal procedures.

The plethysmographic variability index does not predict fluid responsiveness estimated by esophageal Doppler during kidney transplantation: A controlled study.

Research is ongoing to find a noninvasive method of monitoring, which can predict fluid responsiveness in patients undergoing kidney transplantation.To compare the responses to fluid challenges with the Pleth Variability Index, a noninvasive dynamic index derived from plethysmographic variability (Radical 7 pulse oximeter; Masimo Corporation, Irvine, CA), and the esophageal Doppler, the criterion standard.Observational study.University hospital; study from May 2011 and May 2012.Forty-eight patients with end-renal function were included and 44 analyzed. Patients with cardiac failure were not eligible.Fluid challenges were administered during maintenance of general anesthesia but before skin incision and repeated if the patient was deemed to be a “responder” (increase in stroke volume ≥10%).The primary endpoint was to assess if the Pleth Variability Index is an accurate predictor of fluid responsiveness.Among 76 fluid challenges, 38 were considered as positive (increase in stroke volume measured by Doppler ≥10%). Pleth Variability Index was similar at baseline between responders and nonresponder patients. Fluid challenges were associated with a significant decrease in Pleth Variability Index in overall cases (12 [8–14] vs 10 [6–17], P = .050), but it was not able to discriminate between responders (12 [8–15] vs 10 [5–15], P = .650) and nonresponders (11 [6–16] vs 8 [5–14], P = .047). The area under the Receiver Operating Characteristic curve for Pleth Variability Index was 0.49 (0.36–0.62).Pleth Variability Index is not an accurate predictor of fluid responsiveness during kidney transplantation.

Comparison of Proaqt/Pulsioflex® and oesophageal Doppler for intraoperative haemodynamic monitoring during intermediate-risk abdominal surgery

ObjectiveTo compare cardiac index (CI) between Proaqt/PulsioFlex® and oesophageal Doppler (OD) and the ability of the PulsioFlex® to track CI changes induced by fluid challenge and secondly to assess the impact of the time interval between two auto-calibrations of PulsioFlex® on the accuracy of the measured CI. MethodsIn a single hospital, 49 intermediate-risk oncologic abdominal surgery patients were included in an observational study. We measured the cardiac Index (CI) provided by OD and by the Proaqt/PulsioFlex® before and after internal calibration, which were performed randomly at specific intervals after the initial one (30, 60, 90 and 120min). The ability to track fluid responsiveness was evaluated by measuring stroke volume variation, pulse pressure variation (PPV) and CI before and after a 250ml fluid challenge and assessed by a receiver operating characteristic curve analysis. ResultsThe percentages of error before calibration were 51, 58, 82, 81% for 30, 60, 90 and 120min, they were 39, 57, 65, and 54% after calibration. Trending ability is assumed by a 93% concordance rate after applying a 15% exclusion zone. The trend interchangeability rate was 13.75%. The area under the curve for fluid responsiveness measured by PPV and SVV PulsioFlex were respectively 0.67 [0.57–0.77], P<0.01 and 0.75 [0.47–0.66], which was not clinically relevant. ConclusionsThe Proaqt/Pulsioflex® system is not equivalent to OD for haemodynamic monitoring during non-vascular abdominal surgery in intermediate-risk patients. More studies are required to define the effect of the auto-calibration on the system.

Cardiac output-based fluid optimization for kidney transplant recipients: a proof-of-concept trial.

Intravenous fluid management for deceased donor kidney transplantation is an important, modifiable risk factor for delayed graft function (DGF). The primary objective of this study was to determine if goal-directed fluid therapy using esophageal Doppler monitoring (EDM) to optimize stroke volume (SV) would alter the amount of fluid given. This randomized, proof-of-concept trial enrolled 50 deceased donor renal transplant recipients. Data collected included patient characteristics, fluid administration, hemodynamics, and complications. The EDM was used to optimize SV in the EDM group. In the control group, fluid management followed the current standard of practice. The groups were compared for the primary outcome of total intraoperative fluid administered. There was no difference in the mean (standard deviation) volume of intraoperative fluid administered to the 24 control and 26 EDM patients [2,307 (750) mL vs 2,675 (842) mL, respectively; mean difference, 368 mL; 95% confidence interval (CI), -87 to +823; P=0.11]. The incidence of complications in the control and EDM groups was similar (15/24 vs 17/26, respectively; P=0.99), as was the incidence of delayed graft failure (8/24 vs 11/26, respectively; P=0.36). Goal-directed fluid therapy did not alter the volume of fluid administered or the incidence of complications. This proof-of-concept trial provides needed data for conducting a larger trial to determine the influence of fluid therapy on the incidence in DGF in deceased donor kidney transplantation. www.clinicaltrials.gov (NCT02512731). Registered 31 July 2015.

Effect of goal-directed haemodynamic therapy on postoperative complications in low–moderate risk surgical patients: a multicentre randomised controlled trial (FEDORA trial)

BackgroundThe aim of this study was to evaluate postoperative complications in patients having major elective surgery using oesophageal Doppler monitor-guided goal-directed haemodynamic therapy (GDHT), in which administration of fluids, inotropes, and vasopressors was guided by stroke volume, mean arterial pressure, and cardiac index. MethodsThe FEDORA trial was a prospective, multicentre, randomised, parallel-group, controlled patient- and observer-blind trial conducted in adults scheduled for major elective surgery. Randomization and allocation were carried out by a central computer system. In the control group, intraoperative fluids were given based on traditional principles. In the GDHT group, the intraoperative goals were to maintain a maximal stroke volume, with mean arterial pressure >70 mm Hg, and cardiac index ≥2.5 litres min−1 m−2. The primary outcome was percentage of patients with moderate or severe postoperative complications during the first 180 days after surgery. ResultsIn total, 450 patients were randomized to the GDHT group (n=224) or control group (n=226). Data from 420 subjects were analysed. There were significantly fewer with complications in the GDHT group (8.6% vs 16.6%, P=0.018). There were also fewer complications (acute kidney disease, pulmonary oedema, respiratory distress syndrome, wound infections, etc.), and length of hospital stay was shorter in the GDHT group. There was no significant difference in mortality between groups. ConclusionsOesophageal Doppler monitor-guided GDHT reduced postoperative complications and hospital length of stay in low–moderate risk patients undergoing intermediate risk surgery, with no difference in mortality at 180 days. Clinical trial registrationISRCTN93543537.

Comparison of Hemodynamic Monitoring between Transesophageal Doppler and Ultrasonography-Guided Inferior Vena Cava Distensibility in Supine versus Prone Position: A Pilot Study.

Introduction:Lung-protective ventilation strategy and prone positioning are the strategies practiced to manage patients suffering from acute respiratory distress syndrome (ARDS). Inferior Vena Cava Distensibility (dIVC) Index has been used for predicting fluid responsiveness (FR) in supine position. We conducted this study to observe the utility of dIVC in prone position in ARDS patients and compare it with esophageal Doppler (ED) parameters.Materials and Methods:After ethical clearance, a prospective observational pilot study was conducted in a 12-bedded tertiary care hospital. Adult ARDS patients who were treated with prone ventilation were included. Informed consent was taken from the relatives. IVC was visualized through right lateral approach both in supine and prone positions. We compared IVC distensibility and ED parameters, first in 45° head up and then in prone. FR was defined as an increase in the stroke volume of ≥15% as measured by ED. The patients with dIVC >18% were assumed to be fluid responsive. Statistical analysis was done using SPSS software version 20.Results:Twenty-five patients met the inclusion criteria. ARDS was (mean P/F ratio 116.64 ± 44.76) mostly due to pulmonary etiology. Out of 25 patients, 10 patients were fluid responsive based on dIVC (cutoff >18%) in supine position. When compared to ED values after passive leg raising, dIVC had a sensitivity and specificity of 77.78% and 81.25%, respectively, in predicting FR with a moderate-to-absolute agreement between the two methods. IVC distensibility showed statistically significant negative correlation with corrected flow time (FTc) values both in supine and in prone positions.Conclusion:IVC variability can be observed in acute respiratory distress syndrome patients in prone position. Inferior Vena Cava Distensibility correlates with flow time in both the positions.

Intraoperative Noninvasive Cardiovascular and Brain Monitoring in the Elderly

The purpose of this work is to provide a brief review of noninvasive cardiovascular and brain monitoring tools that could potentially decrease neurological complications in the perioperative period. Noninvasive continuous blood pressure monitoring, cardiac output monitoring, pulse contour analysis, and esophageal doppler can be combined with electroencephalogram and brain oximetry in order to improve patient safety by detecting cerebral insults early, allowing appropriate intervention to be made. Aging population is one of the most salient and ever-expanding issues affecting healthcare for the foreseeable future. Defining and implementing optimal perioperative care for this aging population is of increasing importance. During surgery, preserving brain perfusion is probably one of the most important parts of hemodynamic management and can be appropriately achieved by using several available cardiovascular and neurologic monitoring tools.

Interpretation of Noninvasive and Invasive Information

Traditional, static measures of resuscitation, such as vital signs, central venous pressure, and pulmonary arterial pressure, provide momentary glimpses evolving hemodynamic states. In patients with shock, these measures of resuscitation are poor indicators of response to therapy. As a result, dynamic assessments of cardiovascular status are now used in critically ill patients to facilitate resuscitation. Some of these approaches focus on fluid responsiveness. These assessments allow care to be tailored to each patient’s response to interventions. An evolving aspect of hemodynamic monitoring is evaluation of the adequacy of tissue perfusion and oxygen delivery. In this review, we consider the use of arterial, central venous, and pulmonary arterial blood pressure monitoring; echocardiography; transesophageal Doppler technology; pulse contour analysis; bioimpedance and bioreactance; and partial rebreathing monitoring modalities to assess hemodynamic status in critically ill patients. This review contains 22 figures, 5 tables, and 38 references. Key words: echocardiography, esophageal Doppler technology, invasive and noninvasive hemodynamic monitoring, pulse contour analysis, shock

Thoracic Epidural Analgesia With Levobupivacaine Reduces Remifentanil and Propofol Consumption Evaluated by Closed-Loop Titration Guided by the Bispectral Index: A Double-Blind Placebo-Controlled Study.

Thoracic epidural analgesia (TEA) combined with general anesthesia decreases anesthetic requirements by half when hemodynamic criteria are used for the titration of analgesia. We therefore determined the impact of TEA on anesthetic requirements, when a closed-loop controller was used allowing the automated coadministration of propofol-remifentanil guided solely by the Bispectral index. This single-center double-blind study enrolled patients scheduled for elective posterolateral thoracotomy using TEA. Patients were randomly assigned to receive a bolus followed by a continuous infusion of levobupivacaine 0.5% (levo group) or saline 0.9% solution (saline group). General anesthesia was performed by the same automated controller. Stroke volume optimization guided by an esophageal Doppler probe was performed before randomization. The primary outcome variable was the amount of remifentanil delivered by the automated controller between skin incision and closure. Major arterial hypotension was recorded. Data are presented as medians [interquartile range] or number (%) RESULTS:: Nineteen adult patients per group completed the study. At similar depth of anesthesia evaluated by the percentage of time with the Bispectral index in the range 40-60 (85 [77-88] vs 83 [72-87]; P = .39), patients with neuraxial block required less remifentanil (0.15 [0.10-0.20] vs 0.23 [0.14-0.25], µg·kg·min; P = .03) and propofol (4.3 [3.7-4.9] vs 5.7 [4.6-7.3] mg·kg·h; P = .005). Major arterial hypotension was similar in both groups (6 [32%] vs 5 [25%]; P = .46; levo versus saline group, respectively). Epidurally administered levobupivacaine allowed a decrease by one-third of remifentanil requirement. After stroke volume optimization, major arterial hypotension was similar between groups.

Diagnostic value of plasma NGAL and intraoperative diuresis for AKI after major gynecological surgery in patients treated within an intraoperative goal-directed hemodynamic algorithm: A substudy of a randomized controlled trial.

ISRCTN 53154834.

Oesophageal Doppler guided goal-directed haemodynamic therapy in thoracic surgery - a single centre randomized parallel-arm trial

BackgroundPostoperative pulmonary and renal complications are frequent in patients undergoing lung surgery. Hyper- and hypovolaemia may contribute to these complications. We hypothesized that goal-directed haemodynamic management based on oesophageal Doppler monitoring would reduce postoperative pulmonary complications in a randomized clinical parallel-arm trial. MethodsOne hundred patients scheduled for thoracic surgery were randomly assigned to either standard haemodynamic management (control group) or goal-directed therapy (GDT group) guided by an oesophageal Doppler monitoring-based algorithm. The primary endpoint was postoperative pulmonary complications, including spirometry. Secondary endpoints included haemodynamic variables, renal, cardiac, and neurological complications, and length of hospital stay. The investigator assessing outcomes was blinded to group assignment. ResultsForty-eight subjects of each group were analysed. Compared to the control group, fewer subjects in the GDT group developed postoperative pulmonary complications (6 vs. 15 patients; P = 0.047), while spirometry did not differ between groups. Compared to the control group, patients of the GDT group showed higher cardiac index (2.9 vs. 2.1 [l min−1 m − 2]; P < 0.001) and stroke volume index (43 vs. 34 [ml m2]; P < 0.001) during surgery. Renal, cardiac and neurological complications did not differ between groups. Length of hospital stay was shorter in the GDT compared to the control group (9 vs. 11 days; P = 0.005). ConclusionsCompared to standard haemodynamic management, oesophageal Doppler monitor-guided GDT was associated with fewer postoperative pulmonary complications and a shorter hospital stay. Clinical trial registrationThe study was registered in the German Clinical Trials Register (DRKS 00006961). https://drks-neu.uniklinik-freiburg.de/drks_web/

Norepinephrine reduces arterial compliance less than phenylephrine when treating general anesthesia‐induced arterial hypotension

During general anesthesia, arterial hypotension is frequent and may be an important contributor to perioperative morbidity. We assessed the effect of a 5μg bolus of Norepinephrine (NA) when compared with 50μg bolus of Phenylephrine (PE) administered to treat hypotension during maintenance anesthesia, on MAP, derived cardiac output and arterial stiffness parameters. Patients scheduled for a neurosurgical procedure under general anesthesia were prospectively included. Monitoring included invasive blood pressure, esophageal Doppler, and arterial tonometer used to estimate central aortic pressure with arterial stiffness parameters, such as augmentation index (Aix). After initial resuscitation, hypotensive episodes were corrected by a bolus administration of NA or PE in a peripheral venous line. There were 269 bolus administrations of vasopressors (149 NA, 120 PE) in 47 patients with no adverse effects detected. A decrease in stroke volume (SV) was observed with PE compared with NA (-18±9% vs. -14±7%, P<0.001). This decrease was associated with an increase in Aix, which was greater for PE than for NA (+10±8% vs. +6±6%, P<0.0001), and a decrease in total arterial compliance greater for PE compared to NA (Ctot=SV/Central Pulse Pressure) (-35±9% vs. -29±10%, P<0.001). This study suggests that 5μg of NA administered as a bolus in a peripheral venous line could treat general anesthesia-induced arterial hypotension with a smaller decrease in SV and arterial compliance when compared to PE.

Comparison of stroke volume measurement between non-invasive bioreactance and esophageal Doppler in patients undergoing major abdominal–pelvic surgery

Bioreactance is a non-invasive technology for measuring stroke volume (SV) in the operating room and critical care setting. We evaluated how the NICOM® bioreactance device performed against the CardioQ® esophageal Doppler monitor in patients undergoing major abdominal-pelvic surgery, focusing on the effect of different hemodynamic interventions. SVNICOM and SVODM were simultaneously measured intraoperatively, including before and after interventions including fluid challenge, vasopressor boluses, peritoneal gas insufflation/removal, and Trendelenburg/reverse Trendelenburg patient positioning. A total of 768 values were collected from 21 patients. Pre- and post-intervention measures were recorded on 155 occasions. Bland-Altman analysis revealed a bias of 8.6ml and poor precision with wide limits of agreement (54 and -37ml) and a percentage error of 50.6%. No improvement in precision was detected after taking into account repeated measurements for each patient (bias: 8ml; limits of agreement: 74 and -59ml). Concordance between changes in SVNICOM and SVODM before and after interventions was also poor: 78.7% (all measures), 82.4% (after vasopressor administration), and 74.3% (after fluid challenge). Using Doppler SV as the reference technique, the area under the receiver operating characteristic curve assessing the ability of the NICOM device to predict fluid responsiveness was 0.81 (0.7-0.9). In patients undergoing major abdomino-pelvic surgery, SV values obtained by NICOM showed neither clinically or statistically acceptable agreement with those obtained by esophageal Doppler. Although, in the setting of this study, bioreactance technology cannot reliably replace esophageal Doppler monitoring, its accuracy for predicting fluid responsiveness was higher, up to approximately 80%. Observational study.

Oesophageal Doppler guided optimization of cardiac output does not increase visceral microvascular blood flow in healthy volunteers.

Oesophageal Doppler monitoring (ODM) is used clinically to optimize cardiac output (CO) and guide fluid therapy. Despite limited experimental evidence, it is assumed that increasing CO increases visceral microvascular blood flow (MBF). We used contrast-enhanced ultrasound (CEUS) to assess whether ODM-guided optimization of CO altered MBF. Sixteen healthy male volunteers (62±3·4years) were studied. Baseline measurements of CO were recorded via ODM. Hepatic and renal MBF was assessed via CEUS. Saline 0·9% was administered to optimize CO according to a standard protocol and repeat CEUS performed. Time-intensity curves were constructed, allowing organ perfusion calculation via time to 5% perfusion (TT5). MBF was assessed via organ perfusion rise time (RT) (5-95%). CO increased (4535±241ml/min versus 5442±329ml/min, P<0·0001) following fluid administration, whilst time to renal (22·48±1·19s versus 20·79±1·31s; P=0·03), but not hepatic (28·13±4·48s versus 26·83±1·53s; P=0·15) perfusion decreased. Time to renal perfusion was related to CO (renal: r=-0·43, P=0·01). Hepatic nor renal RT altered following fluid administration (renal: 9·03±0·86 versus 8·93±0·85s P=0·86; hepatic: 27·86±1·60s versus 30·71±2·19s, P=0·13). No relationship was observed between changes in CO and MBF in either organ (renal: r=-0·17, P=0·54; hepatic: r=-0·07, P=0·80). ODM-optimized CO reduces time to renal perfusion but does not alter renal or hepatic MBF. A lack of relationship between microvascular visceral perfusion and CO following ODM-guided optimization may explain the absence of improved clinical outcome with ODM monitoring.

Beat-by-beat assessment of cardiac afterload using descending aortic velocity-pressure loop during general anesthesia: a pilot study.

Continuous cardiac afterload evaluation could represent a useful tool during general anesthesia (GA) to titrate vasopressor effect. Using beat to beat descending aortic pressure(P)/flow velocity(U) loop obtained from esophageal Doppler and femoral pressure signals might allow to track afterload changes. Methods We defined three angles characterizing the PU loop (alpha, beta and Global After-Load Angle (GALA)). Augmentation index (AIx) and total arterial compliance (Ctot) were measured via radial tonometry. Peripheral Vascular Resistances (PVR) were also calculated. Twenty patients were recruited and classified into low and high cardiovascular (CV) risk group. Vasopressors were administered, when baseline mean arterial pressure (MAP) fell by 20%. Results We studied 118 pairs of pre/post bolus measurements. At baseline, patients in the lower CV risk group had higher cardiac output (6.1 ± 1.7 vs 4.2 ± 0.6L min; p = 0.005), higher Ctot (2.7 ± 1.0 vs 2.0 ± 0.4ml/mmHg, p = 0.033), lower AIx and PVR (13 ± 10 vs 32 ± 11% and 1011 ± 318 vs 1390 ± 327dyns/cm5; p < 0.001 and p = 0.016, respectively) and lower GALA (41 ± 15 vs 68 ± 6°; p < 0.001). GALA was the only PU Loop parameter associated with Ctot, AIx and PVR. After vasopressors, MAP increase was associated with a decrease in Ctot, an increase in AIx and PVR and an increase in alpha, beta and GALA (p < 0.001 for all). Changes in GALA and Ctot after vasopressors were strongly associated (p = 0.004). Conclusions PU Loop assessment from routine invasive hemodynamic optimization management during GA and especially GALA parameter could monitor cardiac afterload continuously in anesthetized patients, and may help clinicians to titrate vasopressor therapy.

The use of the oesophageal Doppler in perioperative medicine: new opportunities in research and clinical practice.

The oesophageal Doppler (OD) is a minimally invasive haemodynamic monitor used in the surgical theatre and the ICU. Using the OD, goal-directed therapy (GDT) has been shown to reduce perioperative complications in high-risk surgical patients. However, most GDT protocols currently in use are limited to stroke volume optimisation. In the present manuscript, we examine the conceptual models behind new OD-based measurements. These would provide the clinician with a comprehensive view of haemodynamic pathophysiology; including pre-load, contractility, and afterload. Specifically, volume status could be estimated using mean systemic filling pressure (MSFP), the pressure to which all intravascular pressures equilibrate during asystole. Using the OD, MSFP could be readily estimated by simultaneous measurements of aortic blood flow and arterial pressure with sequential manoeuvres of increasing airway pressure. This would result in subsequent reductions in cardiac output and arterial pressure and would allow for a linear extrapolation of a static MSFP value to a "zero flow" state. In addition, we also demonstrate that EF is proportional to mean blood flow velocity measured in the descending thoracic aorta with the OD. Furthermore, OD-derived indexes of blood flow velocity and acceleration, as well as force and kinetic energy, can be derived and used for continuous assessment of cardiac contractility at the bedside. Using OD-derived parameters, the different components of afterload: inertia, resistance and elastance, could also be individually determined. The integration of these additional haemodynamic parameters could assist the clinician in optimising and individualising haemodynamic performance in unstable patients.

Comparison of esophageal Doppler and plethysmographic variability index to guide intraoperative fluid therapy for low-risk patients undergoing colorectal surgery

Study objectiveThis study aims to investigate if there is equivalence in volumes of fluid administered when intravenous fluid therapy is guided by Pleth Variability Index (PVI) compared to the established technology of esophageal Doppler in low-risk patients undergoing major colorectal surgery. DesignRandomized controlled trial. SettingOperating room. PatientsForty low-risk patients undergoing elective colorectal surgery. InterventionPatients were monitored by esophageal Doppler and PVI probes and were randomized to have fluid therapy directed by using one of these technologies, with 250 mL boluses of colloid to maintain a maximal stroke volume, or a PVI of less than 14%. MeasurementsAbsolute volumes of fluid volumes given intraoperatively were measured as were 24 hours fluid volumes. Perioperative measurements of lactate and base excess were recorded as were postoperative complications. Main resultThere was no significant difference between PVI and esophageal Doppler groups in mean total fluid administered (1286 vs 1520 mL, P=.300) or mean intraoperative fluid balance (+839 v+1145 mL, P=.150). ConclusionsPVI offers an entirely non-invasive alternative for goal-directed fluid therapy in this group of patients.

Intraoperative fluid management guided by esophageal Doppler monitoring in major abdominal surgery utilizing the enhanced recovery after surgery program: a systematic review protocol.

The objectives of this review are to identify the effectiveness of esophageal Doppler monitoring (EDM) for goal-directed fluid therapy on postoperative outcomes during abdominal surgery when an enhanced recovery after surgery (ERAS) program is implemented.The specific question of this review is: does the guidance of fluid management by EDM versus fluid management without EDM affect the length of hospital stay, occurrence of postoperative infection, hemodynamic stability and 30-day postoperative complication rate in adult patients undergoing major abdominal surgery with ERAS or similar programs?

Goal directed hemodynamic therapy based in esophageal Doppler flow parameters: A systematic review, meta-analysis and trial sequential analysis

BackgroundNumerous studies have compared perioperative esophageal Doppler monitoring (EDM) guided intravascular volume replacement strategies with conventional clinical volume replacement in surgical patients. The use of the EDM within hemodynamic algorithms is called ‘goal directed hemodynamic therapy’ (GDHT). MethodsMeta-analysis of the effects of EDM guided GDHT in adult non-cardiac surgery on postoperative complications and mortality using PRISMA methodology. A systematic search was performed in Medline, PubMed, EMBASE, and the Cochrane Library (last update, March 2015). Inclusion criteria: Randomized clinical trials (RCTs) in which perioperative GDHT was compared to other fluid management. Primary outcomes: Overall complications. Secondary outcomes: Mortality; number of patients with complications; cardiac, renal and infectious complications; incidence of ileus. Studies were subjected to quantifiable analysis, pre-defined subgroup analysis (stratified by surgery, type of comparator and risk); pre-defined sensitivity analysis and trial sequential analysis (TSA). ResultsFifty six RCTs were initially identified, 15 fulfilling the inclusion criteria, including 1368 patients. A significant reduction was observed in overall complications associated with GDHT compared to other fluid therapy (RR=0.75; 95% CI: 0.63–0.89; p=0.0009) in colorectal, urological and high-risk surgery compared to conventional fluid therapy. No differences were found in secondary outcomes, neither in other subgroups. The impact on preventing the development of complications in patients using EDM is high, causing a relative risk reduction (RRR) of 50% for a number needed to treat (NNT)=6. ConclusionsGDHT guided by EDM decreases postoperative complications, especially in patients undergoing colorectal surgery and high-risk surgery. However, no differences versus restrictive fluid therapy and in intermediate-risk patients were found.