Perioperative Cardiac Output Research Articles

OCOSO2: study protocol for a single-blinded, multicentre, randomised controlled trial assessing a central venous oxygen saturation-based goal-directed therapy to reduce postoperative complications in high-risk patients after elective major surgery

BackgroundFluid loading-based goal-directed therapy is a cornerstone of anaesthesia management in major surgery. Its widespread application has contributed to a significant improvement in perioperative morbidity and mortality. In theory, only hypovolemic patients should receive fluid therapy. However, to achieve such a diagnosis, a surrogate marker of cardiac output adequacy must be used. Current methods of fluid loading-based goal-directed therapy do not assess cardiac output adequacy. Nowadays, new devices make it possible to continuously monitor central venous oxygen saturation (ScvO2) and therefore, to assess the adequacy of perioperative cardiac output during surgery. In major surgery, ScvO2-based goal-directed therapy can be used to enhance fluid therapy and improve patient outcomes.MethodsWe designed a prospective, randomised, single-blinded, multicentre controlled superiority study with a 1:1 allocation ratio. Patients to be included will be high-risk major surgery patients (> 50 years old, ASA score > 2, major intra-abdominal or intra-thoracic surgery > 90 min). Patients in the control group will undergo standard fluid loading-based goal-directed therapy, as recommended by the guidelines. Patients in the intervention group will have ScvO2-based goal-directed therapy and receive fluid loading only if fluid responsiveness and cardiac output inadequacy are present. The primary outcome will be the Comprehensive Complication Index on day five postoperatively.DiscussionThis study is the first to address the issue of cardiac output adequacy in goal-directed therapy. Our hypothesis is that cardiac output optimisation during major surgery achieved by continuous monitoring of the ScvO2 to guide fluid therapy will result in a reduction of postoperative complications as compared with current goal-directed fluid therapy practices.Trial registrationClinicalTrials.gov. NCT03828565. Registered on February 4, 2019.

Application of Propofol Target-Controlled Infusion for Optimized Hemodynamic Status in ESRD Patients Receiving Arteriovenous Access Surgery: A Randomized Controlled Trial.

Background and Objectives: End-stage renal disease (ESRD) is associated with increased anesthetic risks such as cardiovascular events resulting in higher perioperative mortality rates. This study investigated the perioperative and postoperative outcomes in ESRD patients receiving propofol target-controlled infusion with brachial plexus block during arteriovenous (AV) access surgery. Materials and Methods: We recruited fifty consecutive patients scheduled to receive AV access surgery. While all patients received general anesthesia combined with ultrasound-guided brachial plexus block, the patients were randomly assigned to one of two general anesthesia maintenance groups, with 23 receiving propofol target-controlled infusion (TCI) and 24 receiving sevoflurane inhalation. We measured perioperative mean arterial pressure (MAP), heart rate, and cardiac output and recorded postoperative pain status and adverse events in both groups. Results: ESRD patients receiving propofol TCI had significantly less reduction in blood pressure than those receiving sevoflurane inhalation (p < 0.05) during AV access surgery. Perioperative cardiac output and heart rate were similar in both groups. Both groups reported relatively low postoperative pain score and a low incidence of adverse events. Conclusions: Propofol TCI with brachial plexus block can be used as an effective anesthesia regimen for ESRD patients receiving AV access surgery. It can be used with less blood pressure fluctuation than inhalational anesthesia.

Perioperative Cardiac Output Monitoring Utilizing Non-pulse Contour Methods

The purpose of this review was to provide an overview of the recent concepts regarding cardiac output measurement devices that utilize non-pulse contour methods, especially in an intraoperative setting. The techniques include inert gas rebreathing method, partial CO2 rebreathing method, impedance cardiography, and its derivative technologies such as electrical velocimetry and bioreactance, transesophageal echocardiography/Doppler, and transthoracic echocardiography/Doppler. We focused on the invasiveness of the devices and their underlying technology. Although various types of cardiac output monitoring devices are available, none of them may be considered as an ideal device in terms of accuracy, trending ability of cardiac output changes, and reproducibility of measurements. There are increasing types of devices applicable for intraoperative use, yet only few data are available regarding the trending ability of cardiac output changes and reproducibility of the measurements. Therefore, the empirical application of these devices for various surgical patients may be done under the consideration of their invasiveness and their underlying technology, and it may provide us with more data over time. The non-pulse contour-derived cardiac output measurement devices are classified according to their underlying principles, which closely reflect their advantages and disadvantages in the perioperative setting.

Randomized comparison of sevoflurane versus propofol-remifentanil on the cardioprotective effects in elderly patients with coronary heart disease

BackgroundIt is skeptical about cardioprotective property of sevoflurane in patients undergoing noncardiac surgery, especially in the elderly patients with coronary heart disease. We hypothesized that long duration of sevoflurane inhalation in noncardiac surgery could ameliorate myocardial damage in such patients.MethodsThis was a randomized, prospective study. One hundred twenty-one elderly patients with coronary heart disease were randomly allocated into two groups. Maintenance of anesthesia was achieved by sevoflurane inhalation (Group S) or propofol-remifentanil respectively (Group PR). Serum cardiac troponin I (cTnI) and brain natriuretic peptide (BNP) were measured before anesthesia induction (T0), 8 h (T1) and 24 h (T2) after anesthesia respectively. The perioperative cardiac output, complications and postoperative 3-month follow-up from end of surgery were recorded.ResultsBetween the two groups, there were no statistical differences in the values of cTnI and BNP during the study. However, The area under the curve of cTnI values over 24 h after operation was less in Group S. Group PR had lower cardiac output and consumed more amount of phenylephrine during the study (P < 0.05).ConclusionsCompared with the group PR, sevoflurane had no benefit in the myocardial protection for the elderly patients with CHD. However, Sevoflurane showed advantage in maintaining hemodynamic stability during the operative period.Trial registrationChinese Clinical Trial Registry, ChiCTR-IPR-16008871, 21 July 2016.

Guiding Goal-Directed Therapy

Several studies have demonstrated that perioperative hemodynamic optimization (or “goal directed therapy”) using minimally invasive hemodynamic monitoring technologies has the ability to improve postoperative patients’ outcome with lower complication rates, shorter hospital lengths of stay, and lower cost of surgery. This specific concept of goal-directed therapy (GDT) uses perioperative cardiac output monitoring and manipulation of physiologic parameters (dynamic parameters of fluid responsiveness) to guide intravenous fluids and inotropic therapy with the goal of ensuring adequate tissue perfusion. Recently, the evidence related to the implementation of GDT strategies has been considered strong enough to allow for the creation of national recommendations in the UK, in France, and by the European Society of Anaesthesiology. The aims of the programs are to apply best practices to high-risk surgical patients and requires the participation of all clinicians involved in patients’ care. Considering the potential clinical and economic benefits of GDT protocols and the positive recommendations from influential scientific societies, more and more hospitals around the world have become interested in implementing hemodynamic optimization in their departments. This review provides the information about the evolution of hemodynamic monitoring from invasive to the more recent noninvasive devices, and how these devices can be used in the operating rooms through well-defined algorithms of GDT.

The effect of perhexiline on myocardial protection during coronary artery surgery: a two-centre, randomized, double-blind, placebo-controlled trial.

OBJECTIVESPerhexiline is thought to modulate metabolism by inhibiting mitochondrial carnitine palmitoyltransferase-1, reducing fatty acid uptake and increasing carbohydrate utilization. This study assessed whether preoperative perhexiline improves markers of myocardial protection in patients undergoing coronary artery bypass graft surgery and analysed its effect on the myocardial metabolome.METHODSIn a prospective, randomized, double-blind, placebo-controlled trial, patients at two centres were randomized to receive either oral perhexiline or placebo for at least 5 days prior to surgery. The primary outcome was a low cardiac output episode in the first 6 h. All pre-specified analyses were conducted according to the intention-to-treat principle with a statistical power of 90% to detect a relative risk of 0.5 and a conventional one-sided α-value of 0.025. A subset of pre-ischaemic left ventricular biopsies was analysed using mass spectrometry-based metabolomics.RESULTSOver a 3-year period, 286 patients were randomized, received the intervention and were included in the analysis. The incidence rate of a low cardiac output episode in the perhexiline arm was 36.7% (51/139) vs 34.7% (51/147) in the control arm [odds ratio (OR) 0.92, 95% confidence interval (CI) 0.56–1.50, P = 0.74]. Perhexiline was associated with a reduction in the cardiac index at 6 h [difference in means 0.19, 95% CI 0.07–0.31, P = 0.001] and an increase in inotropic support in the first 12 h (OR 0.55, 95% CI 0.34–0.89, P = 0.015). There were no significant differences in myocardial injury with troponin-T or electrocardiogram, reoperation, renal dysfunction or length of stay. No difference in the preischaemic left ventricular metabolism was identified between groups on metabolomics analysis.CONCLUSIONSPreoperative perhexiline does not improve myocardial protection in patients undergoing coronary surgery and in fact reduced perioperative cardiac output, increasing the need for inotropic support. Perhexiline has no significant effect on the mass spectrometry-visible polar myocardial metabolome in vivo in humans, supporting the suggestion that it acts via a pathway that is independent of myocardial carnitine palmitoyltransferase inhibition and may explain the lack of clinical benefit observed following surgery.ClinicalTrials.Gov IDNCT00845364.

Hybrid measurement to achieve satisfactory precision in perioperative cardiac output monitoring.

Advanced haemodynamic monitoring employing minimally invasive cardiac output measurement may lead to significant improvements in patient outcomes in major surgery. However, the precision (scatter) of measurement of available generic technologies has been shown to be unsatisfactory with percentage error of agreement with bolus thermodilution (% error) of 40% to 50%. Simultaneous measurement and averaging by two or more technologies may reduce random measurement scatter and improve precision. This concept, called the hybrid method, was tested by comparing accuracy and precision of measurement relative to bolus thermodilution using combinations of three component methods. Thirty patients scheduled for either elective cardiac surgery or liver transplantation were studied. Agreement with simultaneous bolus thermodilution of hybrid combinations of continuous thermodilution (QtCCO) or Vigeleo™/FloTrac™ pulse contour measurement (QtFT) with pulmonary Capnotracking (QtCO2) was assessed pre- and post-cardiopulmonary bypass or pre- and post-reperfusion of the donor liver and compared with that of the component methods alone. Hybridisation of QtCO2 (% error 42.2) and QtCCO (% error 51.3) achieved significantly better precision (% error 31.3) than the component methods (P=0.0004) and (P=0.0195). Due to poor inherent precision of QtFT (% error 82.8), hybrid combination of QtFT with QtCO2 did not result in better precision than QtCO2 alone. Hybrid measurement can approach a 30% error, which is recommended as the upper limit for acceptability. This is a practical option where at least one component method, such as Capnotracking, is automated and does not increase the cost or complexity of the measurement process.

Adherence to the nurse-driven hemodynamic protocol during postoperative care

The aim of this work is to verify that low incidence of hemodynamic interventions in hemodynamically monitored patients in our postoperative ICU is not caused by insufficient attention being paid to the drop of noncalibrated cardiac index (nCI). In the last 2 years there was a need for hemodynamic intervention in 92% of patients with perioperative cardiac output monitoring, while only 31% of these patients needed at least one hemodynamic intervention postoperatively in the ICU.

Pressure recording analytical method for measuring perioperative cardiac output in pediatric cardiac surgery: A validation study

Pressure recording analytical method for measuring perioperative cardiac output in pediatric cardiac surgery: A validation study

A meta‐analysis of the accuracy and precision of the ultrasonic cardiac output monitor (USCOM)

The ultrasonic cardiac output monitor is a non-invasive, continuous-wave Doppler monitor that can be used to measure cardiac output. Its accuracy and precision in peri-operative and critical care has been assessed with varied results. We conducted a meta-analysis to calculate a pooled mean bias, precision and percentage error for this device. Six studies were suitable for inclusion into a pooled parametric analysis consisting of 320 measurements. The mean weighted bias was -0.39 l.min(-1) (95% CI -0.25 to -0.53 l.min(-1) ), precision 1.27 l.min(-1) and percentage error 42.7% (95% CI 38.5-46.9%). The ultrasonic cardiac output monitor achieved similar agreement with bolus thermodilution to that of other minimally invasive methods of peri-operative cardiac output monitoring, and may have a useful role in cardiac output monitoring.

Case Scenario

Case Scenario

Clinical evaluation and advancement of perioperative minimally-invasive cardiac output monitoring methods

Background Perioperative cardiac output (CO) monitoring of critical patients is one of the objective indicators of cardiac functions. In recent years, along with the development of software, perioperative minimally-invasive cardiac output monitoring methods get more and more attractive. Objective To summarize the new progress of perioperative minimally-invasive cardiac output monitoring and objectively evaluate their role of perioperative hemodynamic monitoring. Content The basic principle of perioperative minimally-invasive cardiac output monitoring methods (FTV, PiCCO and Modelflow)were summed up.Enumerate the clinical research to compare their accuracy with invasive(Swan-Ganz) or non-invasive(TEE) cardiac output monitoring methods. Estimate the advantages and limitations of three methods. Trend Perioperative minimally -invasive cardiac output monitoring methods are simple and safe, less trauma, high accuracy and can continuously record cardiac output and related hemodynamic parameters. Perioperative minimally-invasive cardiac output monitoring reflect the state of the cardiovascular system promptly and effectively guide therapy in critical patients undergoing anesthesia. It will be more important and widely used in the future. Key words: Cardiac output; Arterial pulse wave; Thermodilution; Modelflow model

Intraoperative correction of low cardiac output to normal values improves outcome in patients with elective abdominal surgery

Clinically unrecognised hypovolemia [1], low stroke volume and/or cardiac output [1,2] during the intraoperative period represent risk factors for unfavourable postoperative outcome. Several prospective randomized clinical studies have shown a decreased postoperative morbidity and mortality linked to perioperative cardiac output or DO2 stimulation to so-called supranormal values (CI > 4.5 l/min/m2 or DO2I > 600 ml/min/m2) [3]. The objective of our study was to find out whether intraoperative maintenance of at least normal values of cardiac output (i.e. 5-7 l/min) would influence postoperative outcome in a group of elective abdominal surgery patients. The reason to choose normal range of cardiac output as a therapeutic goal was the observation, that average values of intraoperatively measured cardiac output are frequently found in a range lower than normal values in a group of patients with unfavourable postoperative outcome [2].

Colon Infarction After Ruptured Abdominal Aortic Aneurysm

Colon infarction is a lethal complication of ruptured abdominal aortic aneurysm. We compared multiple anatomic, hemodynamic, and clinical features in 25 patients with ruptured abdominal aortic aneurysm who suffered colon ischemia and 25 initial survivors of ruptured abdominal aortic aneurysm in whom this complication did not develop. Prior impressions notwithstanding, preoperative shock or volume administration did not correlate with the development of colon ischemia, nor did aneurysm location, cross-clamp site, graft type, or inferior mesenteric artery patency. However, patients with colon ischemia had a significantly lower perioperative cardiac output and were significantly more likely to have received alpha-adrenergic vasoconstrictor agents. Seventeen patients (68%) with colon ischemia died compared with nine patients (36%) without colon ischemia. Perioperative maintenance of cardiac output and avoidance of alpha-adrenergic vasopressor agents are critical elements in prevention of this lethal complication.