Clinical review: Goal-directed therapy in high risk surgical patients

Role of Crystalloids in the Perioperative Setting: From Basics to Clinical Applications and Enhanced Recovery Protocols

Perioperative fluid management, a critical aspect of major surgeries, is characterized by pronounced stress responses, altered capillary permeability, and significant fluid shifts. Recognized as a cornerstone of enhanced recovery protocols, effective perioperative fluid management is crucial for optimizing patient recovery and preventing postoperative complications, especially in high-risk patients. The scientific literature has extensively investigated various fluid infusion regimens, but recent publications indicate that not only the volume but also the type of fluid infused significantly influences surgical outcomes. Adequate fluid therapy prescription requires a thorough understanding of the physiological and biochemical principles that govern the body's internal environment and the potential perioperative alterations that may arise. Recently published clinical trials have questioned the safety of synthetic colloids, widely used in the surgical field. A new clinical scenario has arisen in which crystalloids could play a pivotal role in perioperative fluid therapy. This review aims to offer evidence-based clinical principles for prescribing fluid therapy tailored to the patient's physiology during the perioperative period. The approach combines these principles with current recommendations for enhanced recovery programs for surgical patients, grounded in physiological and biochemical principles.

Optimization of the target strategy of perioperative infusion therapy based on monitoring data of central hemodynamics in order to prevent complications

Enhanced Recovery After Surgery (ERAS) protocols are increasingly used in the perioperative period around the world. The concept of goal-directed fluid therapy (GDT) is a key element of the ERAS protocols. Inadequate perioperative infusion therapy can lead to a number of complications, including the development of an infectious process, namely surgical site infections, pneumonia, urinary tract infections. Optimal infusion therapy is difficult to achieve with standard parameters (e.g., heart rate, blood pressure, central venous pressure), so there are various methods of monitoring central hemodynamics - from invasive, minimally invasive to non-invasive. The latter are increasingly used in clinical practice. The current evidence base shows that perioperative management, specifically the use of GDT guided by real-time, continuous hemodynamic monitoring, helps clinicians maintain a patient's optimal fluid balance. The manuscript presents the analytical data, which describe the benefits and basic principles of perioperative targeted infusion therapy based on central hemodynamic parameters to reduce the risk of complications.

Recipient pre-existing chronic hypotension is associated with delayed graft function and inferior graft survival in kidney transplantation from elderly donors

BACKGROUND

Pre-existing chronic hypotension affects a percentage of kidney transplanted patients (KTs). Although a relationship with delayed graft function (DGF) has been hypothesized, available data are still scarce and inconclusive.

METHODS

A monocentric retrospective observational study was performed on 1127 consecutive KTs from brain death donors over 11 years (2003-2013), classified according to their pre-transplant Mean Blood Pressure (MBP) as hypotensive (MBP < 80 mmHg) or normal-hypertensive (MBP ≥ 80 mmHg, with or without effective antihypertensive therapy).

RESULTS

Univariate analysis showed that a pre-existing hypotension is associated to DGF occurrence (p<0.01; OR for KTs with MBP < 80 mmHg, 4.5; 95% confidence interval [CI], 2.7 to 7.5). Chronic hypotension remained a major predictive factor for DGF development in the logistic regression model adjusted for all DGF determinants. Adjunctive evaluations on paired grafts performed in two different recipients (one hypotensive and the other one normal-hypertensive) confirmed this assumption. Although graft survival was only associated with DGF but not with chronic hypotension in the overall population, stratification according to donor age revealed that death-censored graft survival was significantly lower in hypotensive patients who received a KT from >50 years old donor.

CONCLUSIONS

Our findings suggest that pre-existing recipient hypotension, and the subsequent hypotension-related DGF, could be considered a significant detrimental factor, especially when elderly donors are involved in the transplant procedure.

Implications of Continuous Noninvasive Finger Cuff Arterial Pressure Device Use during Cesarean Delivery for Goal-Directed Fluid Therapy Preload Optimization: A Randomized Controlled Trial

Background

Although fixed-volume conventional fluid preloading protocol fails to attenuate postspinal hypotension during cesarean delivery, the effect of goal-directed fluid therapy (GDFT) remains less explored. Continuous noninvasive finger cuff arterial pressure monitoring using devices such as the ClearSight System can provide the noninvasive stroke volume value, enabling clinicians to perform GDFT before spinal anesthesia; however, the efficacy of GDFT requires further elucidation.

Method

In total, 71 consecutive full-term pregnant women were randomly divided into a control group (n = 34) and a GDFT group (n = 37). Before spinal anesthesia, the control group received a fixed dose (1000 mL) of crystalloid fluid, but the GDFT group received repeated 3 mL/kg body weight of crystalloid fluid challenges within 3 minutes with a 1-minute interval between each fluid challenge based on the stroke volume incremental changes obtained using the ClearSight System (targeting a stroke volume increase of ≥5% after a fluid challenge). The primary outcome was the incidence of postspinal hypotension. The secondary outcomes were total fluid volume, vasopressor dosage, hemodynamic parameter changes, maternal adverse effects, and neonatal profiles.

Result

Women in the GDFT group received more fluid than did those in the control group (1132 ± 108 vs. 1247 ± 202 mL; p = 0.0044), but the incidence of postspinal hypotension (79.4% vs. 73.0%,; p = 0.5864) and norepinephrine dose (12.5 ± 10.6 vs. 15.1 ± 12.8 mcg, respectively; p = 0.3512) was comparable between the two groups. Fewer women in the GDFT group experienced nausea (61.76% vs. 35.14%; p = 0.0332). Neonatal outcomes (Apgar score and umbilical blood analysis) were comparable and typical in both groups.

Conclusion

ClearSight-guided GDFT did not ameliorate postspinal hypotension but may reduce nausea. This trial is registered with NCT03013140.

Noninvasive estimation of aortic hemodynamics and cardiac contractility using machine learning

Cardiac and aortic characteristics are crucial for cardiovascular disease detection. However, noninvasive estimation of aortic hemodynamics and cardiac contractility is still challenging. This paper investigated the potential of estimating aortic systolic pressure (aSBP), cardiac output (CO), and end-systolic elastance (E_es) from cuff-pressure and pulse wave velocity (PWV) using regression analysis. The importance of incorporating ejection fraction (EF) as additional input for estimating E_es was also assessed. The models, including Random Forest, Support Vector Regressor, Ridge, Gradient Boosting, were trained/validated using synthetic data (n = 4,018) from an in-silico model. When cuff-pressure and PWV were used as inputs, the normalized-RMSEs/correlations for aSBP, CO, and E_es (best-performing models) were 3.36 ± 0.74%/0.99, 7.60 ± 0.68%/0.96, and 16.96 ± 0.64%/0.37, respectively. Using EF as additional input for estimating E_es significantly improved the predictions (7.00 ± 0.78%/0.92). Results showed that the use of noninvasive pressure measurements allows estimating aSBP and CO with acceptable accuracy. In contrast, E_es cannot be predicted from pressure signals alone. Addition of the EF information greatly improves the estimated E_es. Accuracy of the model-derived aSBP compared to in-vivo aSBP (n = 783) was very satisfactory (5.26 ± 2.30%/0.97). Future in-vivo evaluation of CO and E_es estimations remains to be conducted. This novel methodology has potential to improve the noninvasive monitoring of aortic hemodynamics and cardiac contractility.

Goal-Directed Therapy for Cardiac Surgery

Goal-directed therapy couples therapeutic interventions with physiologic and metabolic targets to mitigate a patient's modifiable risks for death and complications. Goal-directed therapy attempts to improve quality-of-care metrics, including length of stay, rate of readmission, and cost per case. Debate persists around specific parameters and goals, the risk profiles that may benefit, and associated therapeutic strategies. Goal-directed therapy has demonstrated reduced complication rates and lengths of stay in noncardiac surgery studies. Establishing goal-directed therapy's early promise and role in cardiac surgery-namely, producing fewer complications and deaths-will require larger studies, including those with greater focus on high-risk patients.

Guidelines for Perioperative Care in Cytoreductive Surgery (CRS) with or without hyperthermic IntraPEritoneal chemotherapy (HIPEC): Enhanced recovery after surgery (ERAS®) Society Recommendations - Part I: Preoperative and intraoperative management

BACKGROUND

Enhanced recovery after surgery (ERAS) pathways have been shown to considerably reduce complications, length of stay and costs after most of surgical procedures by standardised application of best evidence-based perioperative care. The aim was to elaborate dedicated recommendations for cytoreductive surgery (CRS) ± hyperthermic intraperitoneal chemotherapy (HIPEC) in a two-part series of guidelines based on expert consensus. The present part I of the guidelines highlights preoperative and intraoperative management.

METHODS

The core group assembled a multidisciplinary panel of 24 experts involved in peritoneal surface malignancy surgery representing the fields of general surgery (n = 12), gynaecological surgery (n = 6), and anaesthesia (n = 6). Experts systematically reviewed and summarized the available evidence on 72 identified perioperative care items, following the GRADE (grading of recommendations, assessment, development, evaluation) system. Final consensus (defined as ≥50%, or ≥70% of weak/strong recommendations combined) was reached by a standardised 2-round Delphi process, regarding the strength of recommendations.

RESULTS

Response rates were 100% for both Delphi rounds. Quality of evidence was evaluated high, moderate low and very low, for 15 (21%), 26 (36%), 29 (40%) and 2 items, respectively. Consensus was reached for 71/72(98.6%) items. Strong recommendations were defined for 37 items, No consensus could be reached regarding the preemptive use of fresh frozen plasma.

CONCLUSION

The present ERAS recommendations for CRS±HIPEC are based on a standardised expert consensus process providing clinicians with valuable guidance. There is an urgent need to produce high quality studies for CRS±HIPEC and to prospectively evaluate recommendations in clinical practice.

Design of an interface for teaching cardiovascular physiology to anesthesia clinicians with a patient simulator connected to a minimally invasive cardiac output monitor (LiDCO rapid®)

Cardiovascular physiology can be simulated in patient simulators but is limited to the simulator monitor curves and parameters, missing some important data that today is known as essential to fluid management and therapeutic decision in critical ill and high-risk surgical patients. Our main objective was to project and implement a unidirectional communication channel between a pre-existing patient simulator and a minimally invasive cardiac output monitor (LiDCO rapid®); a monitor that connects to real patients and interprets the arterial wave. To connect the patient simulator to the hemodynamic monitor, firstly, we had to assess both systems and design a communication channel between them. LiDCO monitor accepts as an input an analog voltage varying between 0 V and 5 V and that every volt is directly proportional to a blood pressure (mmHg) value ranging from 0 mmHg (0 V) to 500 mmHg (5 V). A Raspberry Pi 0 (Rpi0) with a WIFI chip integrated was needed and added to a digital analogue converter connected to the board. We designed a system that allowed us to collect, interpret and modify data, and feed it to the LiDCO rapid® monitor. We had developed a Python® script with three independent threads and a circular buffer to handle the data transmission between both systems. The LiDCO hemodynamic monitor successfully received data sent from our setup like a real patient arterial wave pulse and interpreted it to estimate several hemodynamic parameters, as cardiac output, stroke volume, systemic vascular resistance, pulse pressure variation, and stroke volume variation. The connection between the patient simulator and the LiDCO monitor is being used to create arterial curves and other hemodynamic parameters for clinical scenarios where residents and anesthesiologists can simulate a variety of unstable hemodynamic conditions, preparing them to face similar situations with real patients in a safe environment and with their own monitors.

Evaluation of the relationship between lactacidemia and postoperative complications after surgery for peritoneal carcinomatosis

Background

Cytoreductive surgery was developed as a treatment for peritoneal carcinomatosis. However, this surgery is associated with important complications. The present study aimed to assess the relationship between lactacidemia and the rate of associated complications during the immediate postoperative period in the intensive care unit (ICU) in patients undergoing cytoreductive surgery.

Methods

This was a retrospective observational study. A total of 57 patients underwent cytoreductive surgery. All patients were admitted to the ICU immediately after the surgery. Data on lactic acid levels at the time of admission and discharge from the ICU were collected. Postsurgical complications that occurred during the ICU stay were recorded according to failure-to-rescue analysis and their severity stratified according to the Clavien-Dindo classification.

Results

The lactic acid levels at admission to the ICU were significantly higher in patients who developed complications, with an almost tripled unadjusted relative risk (2.9, 95% CI: 1.6, 5.3), than in those who did not develop complications for the lactacidemia threshold established in the cumulative sum curve graphs. After adjustment for confounding effects, the relative risk became even higher (3.1, 95% CI: 1.8, 3.6). Lactic acid levels were still significantly higher in this group at the time of discharge from the ICU.

Conclusions

Serum lactate level is a risk factor for postoperative complications in patients undergoing cytoreductive surgery for peritoneal carcinomatosis. This study suggests that the risk of developing severe complications almost triples with a lactic acid level of 2.5 mmol/L or higher at the time of admission in the ICU.

Perioperative Fluid Administration in Pancreatic Surgery: a Comparison of Three Regimens

BACKGROUND

Optimization of perioperative fluid management is a controversial issue. Weight-adjusted, fixed fluid strategies do not take into account patient hemodynamic status, so that individualized strategies guided by relevant variables may be preferable. We studied this issue in patients undergoing pancreatic surgery within our institution.

METHODS

All patients who underwent a laparotomy for pancreatic cancer during a 5-month period at our hospital (AOUI of Verona, Italy) were eligible to be included in this prospective, observational study. According to the responsible anesthesiologist's free choice, patients received, during surgery, either liberal (12 ml/kg/h) or restricted (4 ml/kg/h) fixed-volume weight-guided replacement fluids or goal-directed (GD) fluid replacement using stroke volume variation (SVV) determined by the FloTrac Vigileo device.

RESULTS

Eighty-six patients were included: 29 in the liberal group, 23 in the restricted group, and 34 in the GD group. The mean duration of surgery was 6 [4-7] h. Patients in the liberal group received more perioperative fluid than those in the GD and restricted groups. Nearly one third of all patients had a major complication, including delayed enteral feeding, and presented a longer duration of hospital stay. Despite the biases related to our limited cohort, there were significantly fewer postoperative complications (such as postoperative fistula, abdominal collection, and hemorrhage) in the restricted and GD groups of patients than in the liberal one.

CONCLUSION

In patients undergoing pancreatic surgery, a restricted or individually guided GD strategy for management of perioperative fluids can result in fewer complications than a liberal fluid strategy. Larger and randomized investigations are warranted to confirm these data on this domain.

Intraoperative Oxygen Delivery and Acute Kidney Injury after Liver Transplantation

Although intraoperative hemodynamic variables were reported to be associated with acute kidney injury (AKI) after liver transplantation, the time-dependent association between intraoperative oxygen delivery and AKI has not yet been evaluated. We reviewed 676 cases of liver transplantation. Oxygen delivery index (DO2I) was calculated at least ten times during surgery. AKI was defined according to the Kidney Disease Improving Global Outcomes criteria. The area under the curve (AUC) was calculated as below a DO2I of 300 (AUC < 300), 400 and 500 mL/min/m2 threshold. Also, the cumulative time below a DO2I of 300 (Time < 300), 400, and 500 mL/min/m2 were calculated. Multivariable logistic regression analysis was performed to evaluate whether AUC < 300 or time < 300 was independently associated with the risk of AKI. As a sensitivity analysis, propensity score matching analysis was performed between the two intraoperative mean DO2I groups using a cutoff of 500 ml/min/m2, and the incidence of AKI was compared between the groups. Multivariable analysis showed that AUC < 300 or time < 300 was an independent predictor of AKI (AUC < 300: odds ratio [OR] = 1.10, 95% confidence interval [CI] 1.06-1.13, time < 300: OR = 1.10, 95% CI 1.08-1.14). Propensity score matching yielded 192 pairs of low and high mean DO2I groups. The incidence of overall and stage 2 or 3 AKI was significantly higher in the lower DO2I group compared to the higher group (overall AKI: lower group, n = 64 (33.3%) vs. higher group, n = 106 (55.2%), P < 0.001). In conclusion, there was a significant time-dependent association between the intraoperative poor oxygen delivery <300 mL/min/m2 and the risk of AKI after liver transplantation. The intraoperative optimization of oxygen delivery may mitigate the risk of AKI.

Noninvasive Cardiac Output and Central Systolic Pressure From Cuff-Pressure and Pulse Wave Velocity

GOAL

We introduce a novel approach to estimate cardiac output (CO) and central systolic blood pressure (cSBP) from noninvasive measurements of peripheral cuff-pressure and carotid-to-femoral pulse wave velocity (cf-PWV).

METHODS

The adjustment of a previously validated one-dimensional arterial tree model is achieved via an optimization process. In the optimization loop, compliance and resistance of the generic arterial tree model as well as aortic flow are adjusted so that simulated brachial systolic and diastolic pressures and cf-PWV converge towards the measured brachial systolic and diastolic pressures and cf-PWV. The process is repeated until full convergence in terms of both brachial pressures and cf-PWV is reached. To assess the accuracy of the proposed framework, we implemented the algorithm on in vivo anonymized data from 20 subjects and compared the method-derived estimates of CO and cSBP to patient-specific measurements obtained with Mobil-O-Graph apparatus (central pressure) and two-dimensional transthoracic echocardiography (aortic blood flow).

RESULTS

Both CO and cSBP estimates were found to be in good agreement with the reference values achieving an RMSE of 0.36 L/min and 2.46 mmHg, respectively. Low biases were reported, namely -0.04 ± 0.36 L/min for CO predictions and -0.27 ± 2.51 mmHg for cSBP predictions.

SIGNIFICANCE

Our one-dimensional model can be successfully "tuned" to partially patient-specific standards by using noninvasive, easily obtained peripheral measurement data. The in vivo evaluation demonstrated that this method can potentially be used to obtain central aortic hemodynamic parameters in a noninvasive and accurate way.

Deep Learning-Based Stroke Volume Estimation Outperforms Conventional Arterial Contour Method in Patients with Hemodynamic Instability

Although the stroke volume (SV) estimation by arterial blood pressure has been widely used in clinical practice, its accuracy is questionable, especially during periods of hemodynamic instability. We aimed to create novel SV estimating model based on deep-learning (DL) method. A convolutional neural network was applied to estimate SV from arterial blood pressure waveform data recorded from liver transplantation (LT) surgeries. The model was trained using a gold standard referential SV measured via pulmonary artery thermodilution method. Merging a gold standard SV and corresponding 10.24 seconds of arterial blood pressure waveform as an input/output data set with 2-senconds of sliding overlap, 484,384 data sets from 34 LT surgeries were used for training and validation of DL model. The performance of DL model was evaluated by correlation and concordance analyses in another 491,353 data sets from 31 LT surgeries. We also evaluated the performance of pre-existing commercialized model (EV1000), and the performance results of DL model and EV1000 were compared. The DL model provided an acceptable performance throughout the surgery (r = 0.813, concordance rate = 74.15%). During the reperfusion phase, where the most severe hemodynamic instability occurred, DL model showed superior correlation (0.861; 95% Confidence Interval, (CI), 0.855-0.866 vs. 0.570; 95% CI, 0.556-0.584, P < 0.001) and higher concordance rate (90.6% vs. 75.8%) over EV1000. In conclusion, the DL-based model was superior for estimating intraoperative SV and thus might guide physicians to precise intraoperative hemodynamic management. Moreover, the DL model seems to be particularly promising because it outperformed EV1000 in circumstance of rapid hemodynamic changes where physicians need most help.

Development and implementation of a comprehensive spine surgery enhanced recovery after surgery protocol: the Cleveland Clinic experience

Enhanced recovery after surgery (ERAS) protocols have been shown to be effective at reducing perioperative morbidity and costs while improving outcomes. To date, spine surgery protocols have been limited in scope, focusing only on specific types of procedures or specific parts of the surgical episode. The authors describe the creation and implementation of one of the first comprehensive ERAS protocols for spine surgery. The protocol is unique in that it has a comprehensive perioperative paradigm encompassing the entire surgical period that is tailored based on the complexity of each individual spine patient.

Perioperative Fluid Management in the Enhanced Recovery after Surgery (ERAS) Pathway

Fluid management is an essential component of the Enhanced Recovery after Surgery (ERAS) pathway. Optimal management begins in the preoperative period and continues through the intraoperative and postoperative phases. In this review, we outline current evidence-based practices for fluid management through each phase of the perioperative period. Preoperatively, patients should be encouraged to hydrate until 2 hours prior to the induction of anesthesia with a carbohydrate-containing clear liquid. When mechanical bowel preparation is necessary, with modern isoosmotic solutions, fluid repletion is not necessary. Intraoperatively, fluid therapy should aim to maintain euvolemia with an individualized approach. While some patients may benefit from goal-directed fluid therapy, a restrictive, zero-balance approach to intraoperative fluid management may be reasonable. Postoperatively, early initiation of oral intake and cessation of intravenous therapy are recommended.

Impact of a goal-directed fluid therapy on length of hospital stay and costs of hepatobiliarypancreatic surgery: a prospective observational study

AIM

The effectiveness of goal-directed fluid therapy (GDFT) algorithms in improving postoperative outcomes has extensively been suggested. Nevertheless, there is a lack of strong evidence regarding both the clinical impact and the cost-effectiveness of the GDFT protocols. The aim of this study is to evaluate the costs of patients undergoing hepatobiliopancreatic surgery when a GDFT protocol is applied. Materials & methods: Consecutive ASA I-III patients undergoing hepatobiliopancreatic surgery were included in this prospective observational study. Depending on device availability, patients were handled either by fluid therapy guided by Vigileo monitor-derived hemodynamic variables (Vigileo-GDFT group) or by standard fluid treatment (standard group). Postoperative length of stay and economic costs were analyzed.

RESULTS

In total, 147 patients were included (71 in the Vigileo-GDFT group and 76 in the standard group). The total hospital length of stay was 13 (median, 1st-3rd quartile, 9-20) days for the Vigileo-GDFT group and 14 (8-21) days for the standard group (p = 0.58); no statistically significant differences between the two groups emerged regarding costs and postoperative complications. In both groups, complications were the main contributor to total cost sustained.

CONCLUSION

The application of a GDFT algorithm did not reduce the total length of hospital stay and the global costs, which were mainly influenced by the number of complications.

A Review of Goal-Directed Cardiopulmonary Bypass Management in Pediatric Cardiac Surgery

Cardiopulmonary bypass perfusion management significantly affects postoperative outcomes. In recent years, the principles of goal-directed therapy have been applied to the field of cardiothoracic surgery to improve patient outcomes. Goal-directed therapy involves continuous peri- and postoperative monitoring of vital clinical parameters to tailor perfusion to each patient's specific needs. Closely measured parameters include fibrinogen, platelet count, lactate, venous oxygen saturation, central venous oxygen saturation, mean arterial pressure, perfusion flow rate, and perfusion pulsatility. These parameters have been shown to influence postoperative fresh frozen plasma transfusion rate, coagulation state, end-organ perfusion, and mortality. In this review, we discuss the recent paradigm shift in pediatric perfusion management toward goal-directed perfusion.

Changes in Hepatic Blood Flow and Liver Function during Closed Abdominal Hyperthermic Intraperitoneal Chemotherapy following Cytoreduction Surgery

BACKGROUND

The increase in intra-abdominal pressure (IAP) during closed abdominal hyperthermic intraperitoneal chemotherapy (HIPEC) leads to major haemodynamic changes and potential organ dysfunction. We investigated these effects on hepatic blood flow (HBF) and liver function in patients undergoing HIPEC following cytoreductive surgery and fluid management guided by dynamic preload indices.

METHODS

In this prospective observational clinical study including 15 consecutive patients, we evaluated HBF by transesophageal echocardiography and liver function by determination of the indocyanine green plasma disappearance rate (ICG-PDR). Friedman's two-way analysis of variance by ranks and Wilcoxon signed-rank test were performed for statistical analysis.

RESULTS

During HIPEC, HBF was markedly reduced, resulting in the loss of any pulsatile Doppler flow signal in all but one patient. The ICG-PDR, expressed as median (interquartile 25-75), decreased from 23 (20-30) %/min to 18 (12.5-19) %/min (p < 0.001). Despite a generous crystalloid infusion rate (27 (22-35) ml/kg/h), cardiac index decreased during the increased IAP period, inferior vena cava diameter decreased, stroke volume variation and pulse pressure variation increased, lung compliance dropped, and there was an augmentation in plateau pressure. All changes were significant (p < 0.001) and reversed to baseline values post HIPEC.

CONCLUSION

Despite optimizing intravenous fluids during closed abdominal HIPEC, we observed a marked decrease in HBF and liver function. Both effects were transient and limited to the period of HIPEC but could influence the choice between closed or open abdominal cavity procedure for HIPEC and should be considered in similar clinical situations of increased IAP.

Significance of perioperative goal-directed hemodynamic approach in preventing postoperative complications in patients after cardiac surgery: a meta-analysis and systematic review

PURPOSE

Goal-directed hemodynamic therapy (GDT) is used to prevent hypoperfusion resulting from surgery. The objective of this study was to analyze the efficacy and importance of perioperative GDT.

METHODS

PUBMED, MEDLINE, CENTRAL, and Google Scholar databases were searched until 17 June 2016 using the search terms: cardiac output, cardiac surgical procedures, hemodynamics, goal-directed therapy, and intraoperative. Randomized-controlled trials with pre-emptive hemodynamic intervention for cardiac surgical population versus standard hemodynamic therapy were included.

RESULTS

Nine studies were included with a total of 1148 patients. The overall analysis revealed no significant difference in the all-cause mortality (pooled peto OR =0.58, 95%CI =0.27-1.525, p = 0.164), duration of mechanical ventilation (pooled difference in mean= -1.48, 95%CI= -3.24 to 0.28, p = 0.099), or length of intensive care unit (ICU) stay (pooled difference in mean= -9.10, 95%CI= -20.14 to 1.93, p = 0.106) between patients in the GDT and control groups. Patients in the GDP group were associated with shorter hospital stay than those in the control group (pooled difference in mean= -1.52, 95%CI= -2.31 to -0.73, p < 0.001).

CONCLUSION

GDT reduces the length of hospital stay compared with the standard of care. Further studies are necessary to continually assess the benefit of GDT following major surgery. Key Messages The results of this analysis revealed no significant difference between cardiac surgery patients receiving goal-directed hemodynamic therapy (GDT) or conventional fluid therapy in terms of the all-cause mortality, duration of mechanical intervention, and length of ICU-stay. The length of hospital stay was significantly reduced in patients treated with GDT compare to conventional fluid therapy. GDT may have limited benefit in reducing mortality; however, the association to shorter length of hospital stay may suggest that better hemodynamic balance can facilitate postoperative recovery.

Best practice for perioperative management of patients with cytoreductive surgery and HIPEC

Due to the significantly improved outcome and quality of life of patients with different tumor entities after cytoreductive surgery (CRS) and HIPEC, there is an increasing number of centers performing CRS and HIPEC procedures. As this procedure is technically challenging with potential high morbidity and mortality, respectively, institutional experience also in the anesthetic and intensive care departments is essential for optimal treatment and prevention of adverse events. Clinical pathways have to be developed to achieve also good results in more comorbid patients with border line indications and extensive surgical procedures. The anesthesiologist has deal with relevant fluid, blood and protein losses, increased intraabdominal pressure, systemic hypo-/hyperthermia, and increased metabolic rate in patients undergoing cytoreductive surgery with HIPEC. It is of utmost importance to maintain or restore an adequate volume by aggressive substitution of intravenous fluids, which counteracts the increased fluid loss and venous capacitance during this procedure. Supplementary thoracic epidural analgesia, non-invasive ventilation, and physiotherapy are recommended to guarantee adequate pain therapy and postoperative extubation as well as fast-track concepts. Advanced hemodynamic monitoring is essential to help the anesthesiologist picking up information about the real-time fluid status of the patient. Preoperative preconditioning is mandatory in patients scheduled for HIPEC surgery and will result in improved outcome. Postoperatively, volume status optimization, early nutritional support, sufficient anticoagulation, and point of care coagulation management are essential. This is an extensive update on all relevant topics for anesthetists and intensivists dealing with CRS and HIPEC.

Perioperative fluid volume optimization following proximal femoral fracture

BACKGROUND

Proximal femoral fracture (PFF) is a common orthopaedic emergency that affects mainly elderly people at high risk of complications. Advanced methods for managing fluid therapy during treatment for PFF are available, but their role in reducing risk is unclear.

OBJECTIVES

To compare the safety and effectiveness of the following methods of perioperative fluid optimization in adult participants undergoing surgical repair of hip fracture: advanced invasive haemodynamic monitoring, such as transoesophageal Doppler and pulse contour analysis; a protocol using standard measures, such as blood pressure, urine output and central venous pressure; and usual care.Comparisons of fluid types (e.g. crystalloid vs colloid) and other methods of optimizing oxygen delivery, such as blood product therapies and pharmacological treatment with inotropes and vasoactive drugs, are considered in other reviews.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2015, Issue 9); MEDLINE (October 2012 to September 2015); and EMBASE (October 2012 to September 2015) without language restrictions. We ran forward and backward citation searches on identified trials. We searched ClinicalTrials.gov and the World Health Organization (WHO) International Clinical Trials Registry Platform for unpublished trials. This is an updated version of a review published originally in 2004 and updated first in 2013 and again in 2015. Original searches were performed in October 2003 and October 2012.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) in adult participants undergoing surgical treatment for PFF that compared any two of advanced haemodynamic monitoring, protocols using standard measures or usual care, irrespective of blinding, language or publication status.

DATA COLLECTION AND ANALYSIS

Two review authors assessed the impact of fluid optimization interventions on outcomes of mortality, length of hospital stay, time to medical fitness, whether participants were able to return to pre-fracture accommodation at six months, participant mobility at six months and adverse events in-hospital. We pooled data using risk ratio (RR) or mean difference (MD) for dichotomous or continuous data, respectively, on the basis of random-effects models.

MAIN RESULTS

We included in this updated review five RCTs with a total of 403 participants, and we added two new trials identified during the 2015 search. One of the included studies was found to have a high risk of bias; no trial featured all pre-specified outcomes. We found two trials for which data are awaited for classification and one ongoing trial.Three studies compared advanced haemodynamic monitoring with a protocol using standard measures; three compared advanced haemodynamic monitoring with usual care; and one compared a protocol using standard measures with usual care. Meta-analyses for the two advanced haemodynamic monitoring comparisons are consistent with both increased and decreased risk of mortality (RR Mantel-Haenszel (M-H) random-effects 0.41, 95% confidence interval (CI) 0.14 to 1.20; 280 participants; RR M-H random-effects 0.45, 95% CI 0.07 to 2.95; 213 participants, respectively). The study comparing a protocol with usual care found no difference between groups for this outcome.Three studies comparing advanced haemodynamic monitoring with usual care reported data for length of stay and time to medical fitness. There was no statistically significant difference between groups for these outcomes in the two studies that we were able to combine (MD IV fixed 0.63, 95% CI -1.70 to 2.96); MD IV fixed 0.01, 95% CI -1.74 to 1.71, respectively) and no statistically significant difference in the third study. One study reported reduced time to medical fitness when comparing advanced haemodynamic monitoring with a protocol, and when comparing protocol monitoring with usual care.The number of participants with one or more complications showed no statistically significant differences in each of the two advanced haemodynamic monitoring comparisons (RR M-H random-effects 0.83, 95% CI 0.59 to 1.17; 280 participants; RR M-H random-effects 0.72, 95% CI 0.40 to 1.31; 173 participants, respectively), nor any differences in the protocol and usual care comparison.Only one study reported the number of participants able to return to normal accommodation after discharge with no statistically significant difference between groups.There were few studies with a small number of participants, and by using the GRADE (Grades of Recommendation, Assessment, Development and Evaluation Working Group) approach, we judged the quality of the outcome evidence as low. We had included one study with a high risk of bias, but upon applying GRADE, we downgraded the quality of this outcome evidence to very low.

AUTHORS' CONCLUSIONS

Five studies including a total of 403 participants provided no evidence that fluid optimization strategies improve outcomes for participants undergoing surgery for PFF. Further research powered to test some of these outcomes is ongoing.

Fluid Administration, Vasopressor Use and Patient Outcomes in a Group of High-Risk Cardiac Surgical Patients Receiving Postoperative Goal-Directed Haemodynamic Therapy: A Pilot Study

The role of goal-directed therapy in high-risk cardiac surgical patients has not been determined. This study sought to observe the effect of a postoperative standardised haemodynamic protocol (SHP) on the administration of fluid and vasoactive drugs after high-risk cardiac surgery. This was an interventional pilot study. In 2010 to 2011, the SHP was introduced to the ICU at Wellington Regional Hospital, Wellington, New Zealand, for the perioperative management of patients undergoing high-risk cardiac surgery. A pulmonary artery catheter was inserted in the patients in the study group and fluids and supportive medications were provided in the ICU according to a protocol that targeted a cardiac index ≥2 l/min/m2, mixed venous oxygen saturation ≥60% and a mean arterial pressure of 65 to 75 mmHg. Data from 40 consecutive high-risk cardiac surgical patients assigned to this protocol were compared with a matched cohort of 40 consecutive high-risk cardiac surgical patients receiving ‘usual care’ in 2009. Baseline characteristics were similar in the two groups. There was no significant difference in the duration of noradrenaline infusion in the SHP cohort compared to historical controls (median [IQR] 18.5 hours [31.63] versus 18 hours [18.3]; P=0.35), despite patients receiving more fluid in their first 12 hours in the ICU (mean 4687 ml [SD±2284 ml] versus 1889 ml [SD±1344 ml]; P <0.001). The SHP cohort had a higher rate of reintubation (4 in 37 [10.8%] versus 0 in 40 [0%]; P=0.049). The SHP delivered significantly more fluid, but did not reduce the duration of noradrenaline infusion, compared to usual care.

Defining goals of resuscitation in the critically ill patient

There is still no "universal" consensus on an optimal endpoint for goal directed therapy (GDT) in the critically ill patient. As in other areas of medicine, this should help providers to focus on a more "individualized approach" rather than a protocolized approach to ensure proper patient care. Hemodynamic optimization needs more than simply blood pressure, heart rate, central venous pressure and urine output monitoring. It is essential to also monitor flow variables (cardiac output/stroke volume) and dynamic parameters of fluid responsiveness whenever available. This article will provide a review of current and trending approaches of the goals of resuscitation in the critically ill patient.

Stroke volume variation to guide fluid therapy: is it suitable for high-risk surgical patients? A terminated randomized controlled trial

Background

Perioperative goal-directed fluid therapy (GDFT) may improve outcome after high-risk surgery. Minimal invasive measurement of stroke volume variation (SVV) has been recommended to guide fluid therapy. We intended to study how perioperative GDFT with arterial-based continuous SVV monitoring influences postoperative complications in a high-risk surgical population.

Methods

From February 1st 2012, all ASA 3 and 4 patients undergoing abdominal surgery in two university hospitals were assessed for randomization into a control group or GDFT group. An arterial-line cardiac output monitor was used to measure SVV, and fluid was given after an algorithm in the intervention group. Restrictions of the method excluded patients undergoing laparoscopic surgery, patients with atrial fibrillation and patients with severe mitral/aortal stenosis. To detect a decrease in number of complication from 40 % in the control group to 20 % in the GDFT group, n = 164 patients were needed (power 80 %, alpha 0.05, two-sided test). To include the needed amount of patients, the study was estimated to last for 2 years.

Results

After 1 year, 30 patients were included and the study was halted due to slow inclusion rate. Of 732 high-risk patients scheduled for abdominal surgery, 391 were screened for randomization. Of those, n = 249 (64 %) were excluded because a laparoscopic technique was preferred and n = 95 (24 %) due to atrial fibrillation.

Conclusions

Our study was stopped due to a slow inclusion rate. Methodological restrictions of the arterial-line cardiac output monitor excluded the majority of patients. This leaves the question if this method is appropriate to guide fluid therapy in high-risk surgical patients.

Trial registration

ClinicalTrials.gov: NCT01473446.

Electronic supplementary material

The online version of this article (doi:10.1186/s13741-015-0016-x) contains supplementary material, which is available to authorized users.

Outcomes of implementation of enhanced goal directed therapy in high-risk patients undergoing abdominal surgery

Background and Aims:

Advanced monitoring targeting haemodynamic and oxygenation variables can improve outcomes of surgery in high-risk patients. We aimed to assess the impact of goal directed therapy (GDT) targeting cardiac index (CI) and oxygen extraction ratio (O₂ER) on outcomes of high-risk patients undergoing abdominal surgery.

Methods:

In a prospective randomised trial, forty patients (American Society of Anaesthesiologists II and III) undergoing major abdominal surgeries were randomised into two groups. In-Group A mean arterial pressure ≥ 65 mmHg, central venous pressure ≥ 8–10 mmHg, urine output ≥ 0.5 mL/kg/h and central venous oxygen saturation ≥ 70% were targeted intra-operatively and 12 h postoperatively. In-Group-B (enhanced GDT), in addition to the monitoring in-Group-A, CI ≥ 2.5 L/min/m² and O₂ER ≤ 27% were targeted. The end-points were lactate levels and base deficit during and after surgery. The secondary end points were length of Intensive Care Unit (ICU) and hospital stay and postoperative complications. Wilcoxon Mann Whitney and Chi-square tests were used for statistical assessment.

Results:

Lactate levels postoperatively at 4 and 8 h were lower in-Group-B (P < 0.05). The mean base deficit at 3, 4, 5 and 6 h intra-operatively and postoperatively after 4, 8 and 12 h were lower in-Group-B (P < 0.05). There were no significant differences in ICU stay (2.10 ± 1.52 vs. 2.90 ± 2.51 days) or hospital stay (10.85 + 4.39 vs. 13.35 + 6.77 days) between Group A and B.

Conclusions:

Implementation of enhanced GDT targeting CI and OER was associated with improved tissue oxygenation.

Goal-directed fluid therapy in gastrointestinal surgery in older coronary heart disease patients: randomized trial

BACKGROUND

Our aim was to determine whether substitution of goal-directed fluid therapy (GDT) (perioperative fluid administration) for traditional therapy to manage elderly patients with coronary heart disease scheduled for gastrointestinal (GI) surgery was advantageous. We determined if it would reduce cardiac complications and shorten time to recovery and discharge.

METHODS

Altogether, 60 of these elderly patients were randomized into GDT (n = 30) and control (n = 30) groups. In the GDT group, fluid management was carried out under guidance of hemodynamic status indicators. Types and quantities of fluids administered, blood loss, intraoperative urine output, time of extubation, intensive care unit (ICU) stay, hospital stay, postoperative adverse cardiac events, and GI complications were recorded.

RESULTS

Total fluids infused were 2,910 ± 645 ml (GDT group) and 3,640 ± 771 ml (control group) (p < 0.05). Numbers of adverse cardiac events in the two groups were not significantly different (p = 0.121). Return of GI function was significantly faster in the GDT group (p < 0.001). Median ICU stay was 32.5 h in the GDT group and 47.5 h in the control group (p < 0.001). Median hospital stay was 18 days in the GDT group and 22 days in the control group (p < 0.001).

CONCLUSIONS

GDT was associated with shorter ICU stay and time to discharge and faster return of GI function compared to traditional fluid therapy. The number of adverse cardiac events was similar in the two groups.

Perioperative fluid therapy: a statement from the international Fluid Optimization Group

BACKGROUND

Perioperative fluid therapy remains a highly debated topic. Its purpose is to maintain or restore effective circulating blood volume during the immediate perioperative period. Maintaining effective circulating blood volume and pressure are key components of assuring adequate organ perfusion while avoiding the risks associated with either organ hypo- or hyperperfusion. Relative to perioperative fluid therapy, three inescapable conclusions exist: overhydration is bad, underhydration is bad, and what we assume about the fluid status of our patients may be incorrect. There is wide variability of practice, both between individuals and institutions. The aims of this paper are to clearly define the risks and benefits of fluid choices within the perioperative space, to describe current evidence-based methodologies for their administration, and ultimately to reduce the variability with which perioperative fluids are administered.

METHODS

Based on the abovementioned acknowledgements, a group of 72 researchers, well known within the field of fluid resuscitation, were invited, via email, to attend a meeting that was held in Chicago in 2011 to discuss perioperative fluid therapy. From the 72 invitees, 14 researchers representing 7 countries attended, and thus, the international Fluid Optimization Group (FOG) came into existence. These researches, working collaboratively, have reviewed the data from 162 different fluid resuscitation papers including both operative and intensive care unit populations. This manuscript is the result of 3 years of evidence-based, discussions, analysis, and synthesis of the currently known risks and benefits of individual fluids and the best methods for administering them.

RESULTS

The results of this review paper provide an overview of the components of an effective perioperative fluid administration plan and address both the physiologic principles and outcomes of fluid administration.

CONCLUSIONS

We recommend that both perioperative fluid choice and therapy be individualized. Patients should receive fluid therapy guided by predefined physiologic targets. Specifically, fluids should be administered when patients require augmentation of their perfusion and are also volume responsive. This paper provides a general approach to fluid therapy and practical recommendations.

Impact of early haemodynamic goal-directed therapy in patients undergoing emergency surgery: an open prospective, randomised trial

Haemodynamic goal-directed therapies (GDT) may improve outcome following elective major surgery. So far, few data exist regarding haemodynamic optimization during emergency surgery. In this randomized, controlled trial, 50 surgical patients with hypovolemic or septic conditions were enrolled and we compared two algorithms of GDTs based either on conventional parameters and pressure pulse variation (control group) or on cardiac index, global end-diastolic volume index and stroke volume variation as derived from the PiCCO monitoring system (optimized group). Postoperative outcome was estimated by a composite index including major complications and by the Sequential Organ Failure Assessment (SOFA) Score within the first 3 days after surgery (POD1, POD2 and POD3). Data from 43 patients were analyzed (control group, N = 23; optimized group, N = 20). Similar amounts of fluid were given in the two groups. Intraoperatively, dobutamine was given in 45 % optimized patients but in no control patients. Major complications occurred more frequently in the optimized group [19 (95 %) versus 10 (40 %) in the control group, P < 0.001]. Likewise, SOFA scores were higher in the optimized group on POD1 (10.2 ± 2.5 versus 6.6 ± 2.2 in the control group, P = 0.001), POD2 (8.4 ± 2.6 vs 5.0 ± 2.4 in the control group, P = 0.002) and POD 3 (5.2 ± 3.6 and 2.2 ± 1.3 in the control group, P = 0.01). There was no significant difference in hospital mortality (13 % in the control group and 25 % in the optimized group). Haemodynamic optimization based on volumetric and flow PiCCO-derived parameters was associated with a less favorable postoperative outcome compared with a conventional GDT protocol during emergency surgery.

Goal-Directed Fluid Therapy Using Stroke Volume Variation for Resuscitation after Low Central Venous Pressure-Assisted Liver Resection: A Randomized Clinical Trial

BACKGROUND

The optimal perioperative fluid resuscitation strategy for liver resections remains undefined. Goal-directed therapy (GDT) embodies a number of physiologic strategies to achieve an ideal fluid balance and avoid the consequences of over- or under-resuscitation.

STUDY DESIGN

In a prospective randomized trial, patients undergoing liver resection were randomized to GDT using stroke volume variation as an end point or to standard perioperative resuscitation. Primary outcomes measure was 30-day morbidity.

RESULTS

Between 2012 and 2014, one hundred and thirty-five patients were randomized (GDT: n = 69; standard perioperative resuscitation: n = 66). Median age was 57 years and 56% were male. Metastatic disease comprised 81% of patients. Overall (35% GDT vs 36% standard perioperative resuscitation; p = 0.86) and grade 3 morbidity (28% GDT vs 18% standard perioperative resuscitation; p = 0.22) were equivalent. Patients in the GDT arm received less intraoperative fluid (mean 2.0 L GDT vs 2.9 L standard perioperative resuscitation; p < 0.001). Perioperative transfusions were required in 4% (6% GDT vs 2% standard perioperative resuscitation; p = 0.37) and boluses in the postanesthesia care unit were administered to 24% (29% GDT vs 20% standard perioperative resuscitation; p = 0.23). Mortality rate was 1% (2 of 135 patients; both in GDT). On multivariable analysis, male sex, age, combined procedures, higher intraoperative fluid volume, and fluid boluses in the postanesthesia care unit were associated with higher 30-day morbidity.

CONCLUSIONS

Stroke volume variation-guided GDT is safe in patients undergoing liver resection and led to less intraoperative fluid. Although the incidence of postoperative complications was similar in both arms, lower intraoperative resuscitation volume was independently associated with decreased postoperative morbidity in the entire cohort. Future studies should target extensive resections and identify patients receiving large resuscitation volumes, as this population is more likely to benefit from this technique.

A randomized trial of goal directed vs. standard fluid therapy in cytoreductive surgery with hyperthermic intraperitoneal chemotherapy

The use of adequate fluid therapy during cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) remains controversial. The aim of the study was to assess whether the use of fluid therapy protocol combined with goal-directed therapy (GDT) is associated with a significant change in morbidity, length of hospital stay, and mortality compared to standard fluid therapy. Patients American Society of Anesthesiologists (ASA) II-III undergoing CRS and HIPEC were randomized into two groups. The GDT group (N = 38) received fluid therapy according to a protocol guided by monitored hemodynamic parameters. The control group (N = 42) received standard fluid therapy. We evaluated incidence of major complications, total length of hospital stay, total amount of fluids administered, and mortality rate. The incidence of major abdominal complications was 10.5% in GDT group and 38.1% in the control group (P = 0.005). The median duration of hospitalization was 19 days in GDT group and 29 days in the control group (P < 0.0001). The mortality rate was zero in GDT group vs. 9.5% in the control group (P = 0.12). GDT group received a significantly (P < 0.0001) lower amount of fluid (5812 ± 1244 ml) than the control group (8269 ± 1452 ml), with a significantly (P < 0.0001) lower volume of crystalloids (3884 ± 1003 vs. 68,528 ± 1413 ml). In CRS and HIPEC, the use of a GDT improves outcome in terms of incidence of major abdominal and systemic postoperative complications and length of hospital stay, compared to standard fluid therapy protocol.

Monitoring needs and goal-directed fluid therapy within an enhanced recovery program

Patients having major abdominal surgery need perioperative fluid supplementation; however, enhanced recovery principles mitigate against many of the factors that traditionally led to relative hypovolemia in the perioperative period. An estimate of fluid requirements for abdominal surgery can be made but individualization of fluid prescription requires consideration of clinical signs and hemodynamic variables. The literature supports goal-directed fluid therapy. Application of this evidence to justify stroke volume optimization in the setting of major surgery within an enhanced recovery program is controversial. This article places the evidence in context, reviews controversies, and suggests implications for current practice and future research.

Clinical Predictors of a Low Central Venous Oxygen Saturation after Major Surgery: A Prospective Prevalence Study

Optimising perioperative haemodynamic status may reduce postoperative complications. In this prospective prevalence study, we investigated the associations between standard haemodynamic parameters and a low central venous oxygen saturation (ScvO2) in patients after major surgery. A total of 201 patients requiring continuous arterial and central venous pressure monitoring after major surgery were recruited. Simultaneous arterial and central venous blood gases, haemodynamic and biochemical data and perfusion index were obtained from patients at a single time-point within 24 hours of surgery. A low ScvO2 (<70%) was observed in 109 patients (54%). Use of mechanical ventilation, mean arterial pressure, central venous pressure, haemoglobin concentrations, arterial pH and lactate concentrations, arterial oxygen (PaO2) and carbon dioxide tensions (PaCO2) were all associated with a low ScvO2 in the univariate analyses. In the multivariate analysis, only a higher perfusion index (odds ratio [OR] 0.87, 95% confidence interval [CI] 0.78 to 0.98), PaO2 (OR 0.98 per mmHg increment, 95% CI 0.97 to 0.99) and PaCO2 (OR 0.88 per mmHg increment, 95% CI 0.82 to 0.95) and a lower central venous pressure (OR 1.14 per mmHg increment, 95% CI 1.04 to 1.25) were significantly associated with a reduced risk of a low ScvO2, all in a linear fashion. In conclusion, PaO2, PaCO2, perfusion index and central venous pressure were significant predictors of a low ScvO2 in patients after major surgery including cardiac surgery, suggesting that ScvO2 should always be interpreted with the arterial blood gases and that liberal perioperative fluid therapy aiming at a high central venous pressure may be detrimental in optimising ScvO2.

Haemodynamic monitoring in the intensive care unit: results from a web-based Swiss survey

Background. The aim of this survey was to describe, in a situation of growing availability of monitoring devices and parameters, the practices in haemodynamic monitoring at the bedside. Methods. We conducted a Web-based survey in Swiss adult ICUs (2009-2010). The questionnaire explored the kind of monitoring used and how the fluid management was addressed. Results. Our survey included 71% of Swiss ICUs. Echocardiography (95%), pulmonary artery catheter (PAC: 85%), and transpulmonary thermodilution (TPTD) (82%) were the most commonly used. TPTD and PAC were frequently both available, although TPTD was the preferred technique. Echocardiography was widely available (95%) but seems to be rarely performed by intensivists themselves. Guidelines for the management of fluid infusion were available in 45% of ICUs. For the prediction of fluid responsiveness, intensivists rely preferentially on dynamic indices or echocardiographic parameters, but static parameters, such as central venous pressure or pulmonary artery occlusion pressure, were still used. Conclusions. In most Swiss ICUs, multiple haemodynamic monitoring devices are available, although TPTD is most commonly used. Despite the usefulness of echocardiography and its large availability, it is not widely performed by Swiss intensivists themselves. Regarding fluid management, several parameters are used without a clear consensus for the optimal method.

Ultrasound-based imaging in neurocritical care patients: a review of clinical applications

OBJECTIVE

To analyze the diagnostic, monitoring, and procedural applications of ultrasound (US) imaging in neurocritical care (NCC) patients.

METHOD

US imaging has been extensively validated in various subset of critically ill patients, but not specifically in the NCC population. We reviewed the clinical applications of US imaging for heart, vascular, brain, and lung evaluation and for possible procedural uses in NCC patients. Major neurosurgical books, journals, testimonials, authors' personal experience, and scientific databases were analyzed.

RESULTS

Cardiac US imaging provides accurate information at NCC arrival to stratify risk factors, including presence of atrial septal defect/patent formen ovale, abnormal ventricular function, or pericardial effusion, and to monitor cardiac anatomy and function during the NCC stay for guiding goal-directed therapy. Vascular US in NCC patients has three especially relevant indications: to screen anatomy and flow in extracranial supra-aortic arteries, to diagnose deep vein thrombosis, and to optimize the safety of central venous catheterization. Brain US has important clinical applications in the NCC, including transcranial Doppler and emerging techniques for cerebral blood flow evaluation with contrast-enhanced US imaging. Lung US, as demonstrated in other intensive care unit patients, provides accurate diagnosis of anatomical and functional abnormalities and enables diagnosis of pleural effusion, pneumothorax, lung consolidation, pulmonary abscess and interstitial-alveolar syndrome, and lung recruitment/derecruitment. US imaging can effectively guide percutaneous tracheostomy.

CONCLUSION

In conclusion, US imaging is an important diagnostic tool that provides real-time information at the bedside to stratify risk, monitor for complications, and guide invasive procedures in NCC patients.

Perioperative fluid volume optimization following proximal femoral fracture

BACKGROUND

Proximal femoral fracture (PFF) is a common orthopaedic emergency, affecting mainly elderly people at high risk of complications. Advanced methods for managing fluid therapy during treatment for PFF are available, but their role in reducing risk is unclear.

OBJECTIVES

To compare the safety and effectiveness of different methods of perioperative fluid optimization in adult participants undergoing surgical repair of hip fracture. We considered the following methods: advanced invasive haemodynamic monitoring, such as transoesophageal Doppler and pulse contour analysis; a protocol using standard measures, such as blood pressure, urine output and central venous pressure; and usual care.Comparisons of fluid types (e.g. crystalloid vs colloid) and other methods of optimizing oxygen delivery, such as blood product therapies and pharmacological treatment with inotropes and vasoactive drugs, are considered elsewhere.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 9); MEDLINE (1966 to October 2012); and EMBASE (1980 to October 2012) without language restrictions. We ran forward and backward citation searches on identified trials. We contacted authors and searched ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform for unpublished trials. This is an updated version of a review published in 2004. The original search was performed in October 2003.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) in adult participants undergoing surgical treatment for PFF, which compared any two of advanced haemodynamic monitoring, protocols using standard measures or usual care, irrespective of blinding, language or publication status.

DATA COLLECTION AND ANALYSIS

Two review authors assessed the impact of fluid optimization interventions on outcomes of mortality, length of hospital stay, return of participant to pre-fracture accommodation and mobility at six months and adverse events in hospital. We pooled data using risk ratio or mean difference for dichotomous or continuous data, respectively, based on random-effects models.

MAIN RESULTS

We included three RCTs with a total of 200 participants. One of these included studies was found to have a high risk of bias; no trial featured all pre-specified outcomes. We found one trial for which data are awaited for classification and two ongoing trials. One included study with low risk of bias found that compared with usual care, time to medical fitness for discharge was shorter with the use of advanced haemodynamic monitoring (mean reduction 6.20 days, 95% CI 2.3 to 10.1 days; 59 participants, one trial) and with the use of protocols that apply standard measures (mean reduction 3.9 days, 95% CI 0.75 to 7.05; 57 participants, one trial). Our results are consistent with both increased and decreased risk of mortality and adverse events in participants receiving the intervention. No data for other outcomes were available. Our results are limited by the quantity of available data.

AUTHORS' CONCLUSIONS

Three studies considering a total of 200 participants reveal an absence of evidence that fluid optimization strategies improve outcomes for participants undergoing surgery for PFF. Length of hospital stay may be improved, but lack of good quality data leaves uncertainty. Further research powered to test some of these outcomes is ongoing.

Haemodynamic optimisation in lower limb arterial surgery: room for improvement?

BACKGROUND

Goal-directed therapy has been proposed to improve outcome in high-risk surgery patients. The aim of this study was to investigate whether individualised goal-directed therapy targeting stroke volume and oxygen delivery could reduce the number of patients with post-operative complications and shorten hospital length of stay after open elective lower limb arterial surgery.

METHODS

Forty patients scheduled for open elective lower limb arterial surgery were prospectively randomised. The LiDCO™plus system was used for haemodynamic monitoring. In the intervention group, stroke volume index was optimised by administering 250 ml aliquots of colloid intraoperatively and during the first 6 h post-operatively. Following surgery, fluid optimisation was supplemented with dobutamine, if necessary, targeting an oxygen delivery index level ≥ 600 ml/min(/) m(2) in the intervention group. Central haemodynamic data were blinded in control patients. Patients were followed up after 30 days.

RESULTS

In the intervention group, stroke volume index, and cardiac index were higher throughout the treatment period (45 ± 10 vs. 41 ± 10 ml/m(2), P < 0.001, and 3.19 ± 0.73 vs. 2.77 ± 0.76 l/min(/) m(2), P < 0.001, respectively) as well as post-operative oxygen delivery index (527 ± 120 vs. 431 ± 130 ml/min(/) m(2), P < 0.001). In the same group, 5/20 patients had one or more complications vs. 11/20 in the control group (P = 0.05). After adjusting for pre-operative and intraoperative differences, the odds ratio for ≥ 1 complications was 0.18 (0.04-0.85) in the intervention group (P = 0.03). The median length of hospital stay did not differ between groups.

CONCLUSION

Perioperative individualised goal-directed therapy may reduce post-operative complications in open elective lower limb arterial surgery.