NICE guidance on CardioQTM oesophageal Doppler monitoring

The Enhanced Recovery after Surgery (ERAS) Pathway Is a Safe Journey for Kidney Transplant Recipients during the "Extended Criteria Donor" Era

Enhanced recovery after surgery (ERAS) protocols are still underused in kidney transplantation (KT) due to recipients’ “frailty” and risk of postoperative complications. We aimed to evaluate the feasibility and safety of ERAS in KT during the “extended-criteria donor” era, and to identify the predictive factors of prolonged hospitalization. In 2010−2019, all patients receiving KT were included in ERAS program targeting a discharge home within 5 days of surgery. Recipient, transplant, and outcomes data were analyzed. Of 454 KT [male: 280, 63.9%; age: 57 (19−77) years], 212 (46.7%) recipients were discharged within the ERAS target (≤5 days), while 242 (53.3%) were discharged later. Patients within the ERAS target (≤5 days) had comparable recipient and transplant characteristics to those with longer hospital stays, and they had similar post-operative complications, readmission rates, and 5 year graft/patient survival. In the multivariate analysis, DGF (HR: 2.16, 95% CI: 1.08−4.34, p < 0.030) and in-hospital dialysis (HR: 3.68, 95% CI: 1.73−7.85, p < 0.001) were the only predictive factors for late discharge. The ERAS approach is feasible and safe in all KT candidates, and its failure is primarily related to the postoperative graft function, rather than the recipient’s clinical status. ERAS pathways, integrated with strict collaboration with local nephrologists, allow early discharge after KT, with clinical benefits.

Cardiac output monitoring - invasive and noninvasive

PURPOSE OF REVIEW

The purpose of this article is to review various contemporary cardiac output (CO) measurement technologies available and their utility in critically ill patients.

RECENT FINDINGS

CO measurement devices can be invasive, minimally invasive, or noninvasive depending upon their method of CO measurement. All devices have pros and cons, with pulmonary artery catheter (PAC) being the gold standard. The invasive techniques are more accurate; however, their invasiveness can cause more complications. The noninvasive devices predict CO via mathematical modeling with several assumptions and are thus prone to errors in clinical situations. Recently, PAC has made a comeback into clinical practice especially in cardiac intensive care units (ICUs). Critical care echocardiography (CCE) is an upcoming tool that not only provides CO but also helps in differential diagnosis. Lack of proper training and nonavailability of equipment are the main hindrances to the wide adoption of CCE.

SUMMARY

PAC thermodilution for CO measurement is still gold standard and most suitable in patients with cardiac pathology and with experienced user. CCE offers an alternative to thermodilution and is suitable for all ICUs; however, structural training is required.

Cardiac output monitoring: Technology and choice

The accurate quantification of cardiac output (CO) is given vital importance in modern medical practice, especially in high-risk surgical and critically ill patients. CO monitoring together with perioperative protocols to guide intravenous fluid therapy and inotropic support with the aim of improving CO and oxygen delivery has shown to improve perioperative outcomes in high-risk surgical patients. Understanding of the underlying principles of CO measuring devices helps in knowing the limitations of their use and allows more effective and safer utilization. At present, no single CO monitoring device can meet all the clinical requirements considering the limitations of diverse CO monitoring techniques. The evidence for the minimally invasive CO monitoring is conflicting; however, different CO monitoring devices may be used during the clinical course of patients as an integrated approach based on their invasiveness and the need for additional hemodynamic data. These devices add numerical trend information for anesthesiologists and intensivists to use in determining the most appropriate management of their patients and at present, do not completely prohibit but do increasingly limit the use of the pulmonary artery catheter.

Best practice & research clinical anaesthesiology: Advances in haemodynamic monitoring for the perioperative patient: Perioperative cardiac output monitoring

Less invasive or even completely non-invasive haemodynamic monitoring technologies have evolved during the last decades. Even established, invasive devices such as the pulmonary artery catheter and transpulmonary thermodilution have still an evidence-based place in the perioperative setting, albeit only in special patient populations. Accumulating evidence suggests to use continuous haemodynamic monitoring, especially flow-based variables such as stroke volume or cardiac output to prevent occult hypoperfusion and, consequently, decrease morbidity and mortality perioperatively. However, there is still a substantial gap between evidence provided by randomised trials and the implementation of haemodynamic monitoring in daily clinical routine. Given the fact that perioperative morbidity and mortality are higher than anticipated and anaesthesiologists are in charge to deal with this problem, the recent advances in minimally invasive and non-invasive monitoring technologies may facilitate more widespread use in the operating theatre, as in addition to costs, the degree of invasiveness of any monitoring tool determines the frequency of its application, at least perioperatively. This review covers the currently available invasive, non-invasive and minimally invasive techniques and devices and addresses their indications and limitations.

Accuracy of Cardiac Output by Nine Different Pulse Contour Algorithms in Cardiac Surgery Patients: A Comparison with Transpulmonary Thermodilution

Objective. Today, there exist several different pulse contour algorithms for calculation of cardiac output (CO). The aim of the present study was to compare the accuracy of nine different pulse contour algorithms with transpulmonary thermodilution before and after cardiopulmonary bypass (CPB). Methods. Thirty patients scheduled for elective coronary surgery were studied before and after CPB. A passive leg raising maneuver was also performed. Measurements included CO obtained by transpulmonary thermodilution (CO_TPTD) and by nine pulse contour algorithms (CO_X1–9). Calibration of pulse contour algorithms was performed by esophageal Doppler ultrasound after induction of anesthesia and 15 min after CPB. Correlations, Bland-Altman analysis, four-quadrant, and polar analysis were also calculated. Results. There was only a poor correlation between CO_TPTD and CO_X1–9 during passive leg raising and in the period before and after CPB. Percentage error exceeded the required 30% limit. Four-quadrant and polar analysis revealed poor trending ability for most algorithms before and after CPB. The Liljestrand-Zander algorithm revealed the best reliability. Conclusions. Estimation of CO by nine different pulse contour algorithms revealed poor accuracy compared with transpulmonary thermodilution. Furthermore, the less-invasive algorithms showed an insufficient capability for trending hemodynamic changes before and after CPB. The Liljestrand-Zander algorithm demonstrated the highest reliability. This trial is registered with NCT02438228 (ClinicalTrials.gov).

Monitoring high-risk patients: minimally invasive and non-invasive possibilities

Over the past decades, there has been considerable progress in the field of less invasive haemodynamic monitoring technologies. Substantial evidence has accumulated, which supports the continuous measurement and optimization of flow-based variables such as stroke volume, that is, cardiac output, in order to prevent occult hypoperfusion and consequently to improve patients' outcome in the perioperative setting. However, there is a striking gap between the developments in haemodynamic monitoring and the increasing evidence to implement defined treatment protocols based on the measured variables, and daily clinical routine. Recent trials have shown that perioperative morbidity and mortality is higher than anticipated. This emphasizes the need for the anaesthesia community to address this issue and promotes the implementation of proven concepts into clinical practice in order to improve patients' outcome, especially in high-risk patients. The advances in minimally invasive and non-invasive monitoring techniques can be seen as a driving force in this respect, as the degree of invasiveness of any monitoring tool determines the frequency of its application, especially in the operating room (OR). From this point of view, we are very confident that some of these minimally invasive and non-invasive haemodynamic monitoring technologies will become an inherent part of our monitoring armamentarium in the OR and in the intensive care unit (ICU).

Using cardiac output monitoring to guide perioperative haemodynamic therapy

PURPOSE OF REVIEW

The aim of this study was to review recent advances and evidence for the use of cardiac output monitors to guide perioperative haemodynamic therapy.

RECENT FINDINGS

There are multiple different cardiac output monitoring devices available for clinical use which are coupled with many different intervention protocols to manipulate perioperative haemodynamics. There is little evidence to demonstrate superiority of any one device. Previous small studies and meta-analyses have suggested that perioperative haemodynamic therapy guided by cardiac output monitoring improves outcomes after major surgery. Despite relatively low-quality evidence several national bodies have recommended 'perioperative goal-directed therapy' (GDT) as a standard of care.Recent larger trials of GDT have mostly failed to prove a benefit of GDT and one explanation for this is the increased quality of usual care that may be occurring because of initiatives such as enhanced recovery after surgery and the WHO Safer Surgery programmes.

SUMMARY

Perioperative GDT remains an exciting intervention to reduce significant morbidity following major surgery; however, it is not yet a proven standard of care. Further large pragmatic trials are required to demonstrate its effectiveness particularly in the era of enhanced recovery after surgery programmes.

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.

Goal-Directed Fluid Therapy Guided by Cardiac Monitoring During High-Risk Abdominal Surgery in Adult Patients: Cost-Effectiveness Analysis of Esophageal Doppler and Arterial Pulse Pressure Waveform Analysis

BACKGROUND

Several minimally invasive techniques for cardiac output monitoring such as the esophageal Doppler (ED) and arterial pulse pressure waveform analysis (APPWA) have been shown to improve surgical outcomes compared with conventional clinical assessment (CCA).

OBJECTIVE

To evaluate the cost-effectiveness of these techniques in high-risk abdominal surgery from the perspective of the French public health insurance fund.

METHODS

An analytical decision model was constructed to compare the cost-effectiveness of ED, APPWA, and CCA. Effectiveness data were defined from meta-analyses of randomized clinical trials. The clinical end points were avoidance of hospital mortality and avoidance of major complications. Hospital costs were estimated by the cost of corresponding diagnosis-related groups.

RESULTS

Both goal-directed therapy strategies evaluated were more effective and less costly than CCA. Perioperative mortality and the rate of major complications were reduced by the use of ED and APPWA. Cost reduction was mainly due to the decrease in the rate of major complications. APPWA was dominant compared with ED in 71.6% and 27.6% and dominated in 23.8% and 20.8% of the cases when the end point considered was "major complications avoided" and "death avoided," respectively. Regarding cost per death avoided, APPWA was more likely to be cost-effective than ED in a wide range of willingness to pay.

CONCLUSIONS

Cardiac output monitoring during high-risk abdominal surgery is cost-effective and is associated with a reduced rate of hospital mortality and major complications, whatever the device used. The two devices evaluated had negligible costs compared with the observed reduction in hospital costs. Our comparative studies suggest a larger effect with APPWA that needs to be confirmed by further studies.

State-of-the-art fluid management in the operating room

The underlying principles guiding fluid management in any setting are very simple: maintain central euvolemia, and avoid salt and water excess. However, these principles are frequently easier to state than to achieve. Evidence from recent literature suggests that avoidance of fluid excess is important, with excessive crystalloid use leading to perioperative weight gain and an increase in complications. A zero-balance approach aimed at avoiding fluid excess is recommended for all patients. For major surgery, there is a sizeable body of evidence that an individualized goal-directed fluid therapy (GDFT) improves outcomes. However, within an Enhanced Recovery program only a few studies have been published, yet so far GDFT has not achieved the same benefit. Balanced crystalloids are recommended for most patients. The use of colloids remains controversial; however, current evidence suggests they can be beneficial in intraoperative patients with objective evidence of hypovolemia.

Peri-operative care of the elderly 2014: Association of Anaesthetists of Great Britain and Ireland

Increasing numbers of elderly patients are undergoing an increasing variety of surgical procedures. There is an age-related decline in physiological reserve, which may be compounded by illness, cognitive decline, frailty and polypharmacy. Compared with younger surgical patients, the elderly are at relatively higher risk of mortality and morbidity after elective and (especially) emergency surgery. Multidisciplinary care improves outcomes for elderly surgical patients. Protocol-driven integrated pathways guide care effectively, but must be individualised to suit each patient. The AAGBI strongly supports an expanded role for senior geriatricians in coordinating peri-operative care for the elderly, with input from senior anaesthetists (consultants/associate specialists) and surgeons. The aims of peri-operative care are to treat elderly patients in a timely, dignified manner, and to optimise rehabilitation by avoiding postoperative complications. Effective peri-operative care improves the likelihood of very elderly surgical patients returning to their same pre-morbid place of residence, and maintains the continuity of their community care when in hospital. Postoperative delirium is common, but underdiagnosed, in elderly surgical patients, and delays rehabilitation. Multimodal intervention strategies are recommended for preventing postoperative delirium. Peri-operative pain is common, but underappreciated, in elderly surgical patients, particularly if they are cognitively impaired. Anaesthetists should administer opioid-sparing analgesia where possible, and follow published guidance on the management of pain in older people. Elderly patients should be assumed to have the mental capacity to make decisions about their treatment. Good communication is essential to this process. If they clearly lack that capacity, proxy information should be sought to determine what treatment, if any, is in the patient's best interests. Anaesthetists must not ration surgical or critical care on the basis of age, but must be involved in discussions about the utility of surgery and/or resuscitation. The evidence base informing peri-operative care for the elderly remains poor. Anaesthetists are strongly encouraged to become involved in national audit projects and outcomes research specifically involving elderly surgical patients.

A randomised prospective trial of intra-operative oesophageal Doppler-guided fluid administration in major gynaecological surgery

Intra-operative oesophageal Doppler monitor-guided fluid management has been associated with improved postoperative length of hospital stay and morbidity in gastrointestinal and orthopaedic surgery. We designed a randomised controlled trial to test the hypothesis that this approach to intra-operative fluid management in major elective open gynaecological surgery would shorten the length of postoperative stay, defined as time to readiness for hospital discharge. Postoperative morbidity was evaluated as a secondary outcome. The oesophageal Doppler monitor group underwent intra-operative fluid management using an oesophageal Doppler-guided stroke volume optimisation algorithm. Control group (conventional fluid therapy) intra-operative fluid management was based on conventional haemodynamic indices. In a single centre, 102 patients were randomly assigned: 51 to the oesophageal Doppler monitor group (51 analysed) and 51 to the control group (50 analysed). Evaluators who were blinded to patient assignment collected postoperative outcome data. There was no difference in the length of postoperative hospital stay between the groups: median (IQR [range]) number of days until ready for discharge was 6 (5-8 [4-25]) days in the oesophageal Doppler monitor group compared with 7 (5-9 [4-42]) days in the control group, p = 0.5. There was no difference between the groups in postoperative morbidity survey scores on postoperative days 1, 3 or 5. Seven patients in the oesophageal Doppler monitor group and 11 in the control group experienced postoperative complications (p = 0.41). These findings question whether intra-operative oesophageal Doppler-guided fluid therapy is of benefit in patients undergoing open gynaecological surgery.

Less invasive methods of advanced hemodynamic monitoring: principles, devices, and their role in the perioperative hemodynamic optimization

The monitoring of the cardiac output (CO) and other hemodynamic parameters, traditionally performed with the thermodilution method via a pulmonary artery catheter (PAC), is now increasingly done with the aid of less invasive and much easier to use devices. When used within the context of a hemodynamic optimization protocol, they can positively influence the outcome in both surgical and non-surgical patient populations. While these monitoring tools have simplified the hemodynamic calculations, they are subject to limitations and can lead to erroneous results if not used properly. In this article we will review the commercially available minimally invasive CO monitoring devices, explore their technical characteristics and describe the limitations that should be taken into consideration when clinical decisions are made.

Comparison of stroke volume and fluid responsiveness measurements in commonly used technologies for goal-directed therapy

STUDY OBJECTIVE

To compare stroke volume (SV) and preload responsiveness measurements from different technologies with the esophageal Doppler monitor (EDM).

DESIGN

Prospective measurement study.

SETTING

Operating room.

PATIENTS

20 ASA physical status 3 patients undergoing vascular, major urological, and bariatric surgery.

INTERVENTIONS

Subjects received fluids using a standard Doppler protocol of 250 mL of colloid administered until SV no longer increased by >10%, and again when the measured SV decreased by 10%.

MEASUREMENTS

Simultaneous readings of SV, stroke volume variation (SVV) and pulse pressure variation (PPV) from the LiDCOrapid, and SVV from the FloTrac/Vigileo were compared with EDM measurements. The pleth variability index (PVI) also was recorded.

MAIN RESULTS

No correlation was seen in percentage SV change as measured by either the LiDCOrapid (r=0.05, P=0.616) or FloTrac (r=0.09, P= 0.363) systems compared with the EDM. Correlation was present between the LiDCOrapid and FloTrac (r=0.515, P<0.0001). Percentage error compared with the EDM was 81% for the FloTrac and 90% for the LiDCOrapid. SVV as measured by LiDCOrapid differed for fluid responders and nonresponders (10% vs 7%; P=0.021). Receiver operator curve analysis to predict a 10% increase in SV from the measured variables showed an area under the curve of 0.57 (95% CI 0.43-0.72) for SVV(FloTrac), 0.64 (95% CI 0.52-0.78) for SVV(LiDCO), 0.61 (95% CI 0.46 -0.76) for PPV, and 0.59 (95% CI 0.46 -0.71) for PVI.

CONCLUSIONS

Stroke volume as measured by the FloTrac and LiDCOrapid systems does not correlate with the esphageal Doppler, has poor concordance, and a clinically unacceptable percentage error. The predictive value of the fluid responsiveness parameters is low, with only SVV measured by the LiDCOrapid having clinical utility.

Pulmonary carbon dioxide elimination for cardiac output monitoring in peri-operative and critical care patients: history and current status

Minimally invasive measurement of cardiac output as a central component of advanced haemodynamic monitoring has been increasingly recognised as a potential means of improving perioperative outcomes in patients undergoing major surgery. Methods based upon pulmonary carbon dioxide elimination are among the oldest techniques in this field, with comparable accuracy and precision to other techniques. Modern adaptations of these techniques suitable for use in the perioperative and critical are environment are based on the differential Fick approach, and include the partial carbon dioxide rebreathing method. The accuracy and precision of this approach to cardiac output measurement has been shown to be similar to other minimally invasive techniques. This paper reviews the underlying principles and evolution of the method, and future directions including recent adaptations designed to deliver continuous breath-by-breath monitoring of cardiac output.

Using bispectral index and cerebral oximetry to guide hemodynamic therapy in high-risk surgical patients

High-risk surgery represents 12.5% of cases but contributes 80% of deaths in the elderly population. Reduction in morbidity and mortality by the use of intervention strategies could result in thousands of lives being saved and savings of up to £400m per annum in the UK. This has resulted in the drive towards goal-directed therapy and intraoperative flow optimization of high-risk surgical patients being advocated by authorities such as the National Institute of Health and Care Excellence and the Association of Anaesthetists of Great Britain and Ireland.Conventional intraoperative monitoring gives little insight into the profound physiological changes occurring as a result of anesthesia and surgery. The build-up of an oxygen debt is associated with a poor outcome and strategies have been developed in the postoperative period to improve outcomes by repayment of this debt. New monitoring technologies such as minimally invasive cardiac output, depth of anesthesia and cerebral oximetry can minimize oxygen debt build-up. This has the potential to reduce complications and lessen the need for postoperative optimization in high-dependency areas.Flow monitoring has thus emerged as essential during intraoperative monitoring in high-risk surgery. However, evidence suggests that current optimization strategies of deliberately increasing flow to meet predefined targets may not reduce mortality.Could the addition of depth of anesthesia and cerebral and tissue oximetry monitoring produce a further improvement in outcomes?Retrospective studies indicate a combination of excessive depth of anesthesia hypotension and low anesthesia requirement results in increased mortality and length of hospital stay.Near infrared technology allows assessment and maintenance of cerebral and tissue oxygenation, a strategy, which has been associated with improved outcomes. The suggestion that the brain is an index organ for tissue oxygenation, especially in the elderly, indicates a role for this technology in the intraoperative period to assess the adequacy of oxygen delivery and reduce the build-up of an oxygen debt.The aim of this article is to make the case for depth of anesthesia and cerebral oximetry alongside flow monitoring as a strategy for reducing oxygen debt during high-risk surgery and further improve outcomes in high-risk surgical patients.

The Role of Intraoperative Fluid Optimization Using the Esophageal Doppler in Advanced Gynecological Cancer: Early Postoperative Recovery and Fitness for Discharge

Objective

To determine the effect of fluid optimization using esophageal Doppler monitoring (EDM) when compared to standard fluid management in women who undergo major gynecological cancer surgery and whether its use is associated with reduced postoperative morbidity.

Methods

From January 2009 to December 2010, women undergoing laparotomy for pelvic masses or uterine cancer had either fluid optimization using intraoperative EDM or standard fluid replacement without using EDM. Cases were selected from 2 surgeons to control for variability in surgical practice. Demographic and surgical details were collected prospectively. Univariate and multivariate analyses were performed to quantify the association between the use of EDM with “early postoperative recovery” and “early fitness for discharge.”

Results

A total of 198 women were operated by the 2 prespecified surgeons; 79 women had fluid optimization with EDM, whereas 119 women had standard anesthetic care. The use of ODM was associated with earlier postoperative recovery (adjusted odds ratio, 2.83; 95% confidence interval, 1.20–6.68; P = 0.02) and earlier fitness for discharge (adjusted odds ratio, 2.81; 95% confidence interval, 1.01–7.78; P = 0.05). Women with advanced-stage disease in the “EDM” group resumed oral diet earlier than women in the “no EDM” group (median, 1 day vs 2 days; P = 0.02). These benefits with EDM did not extend to women with early-stage disease/benign/borderline tumors. No significant difference in postoperative complications was noted.

Conclusions

Intraoperative fluid optimization with EDM in women with advanced gynecological cancer may be associated with improved postoperative recovery and early fitness for discharge. Studies with adequate power are needed to investigate its role in reducing postoperative complications.

A comparison of clinical practice guidelines for proximal femoral fracture

Clinical practice guidelines are designed to assist clinical decision-making by summarising evidence and forming recommendations. The number of available guidelines is vast and they vary in relevance and quality. We reviewed guidelines relevant to the management of a patient with a fractured neck of femur and explored similarities and conflicts between recommendations. As guidelines are often produced in response to an area of clinical uncertainty, recommendations differ. This can result in a situation where the management of a particular clinical problem will depend upon which guideline is followed. We explore the reasons for such differences.