Carotid Blood Flow as a Surrogate for Pulse Contour Analysis in Assessment of Fluid Responsiveness: A Prospective, Observational, Single-Centre Study (Contour Study).

Background and objectives The quest for an accurate and reliable non-invasive method of assessing cardiac output in critically ill patients is still ongoing. Carotid artery Doppler is a promising non-invasive, reproducible, and feasible bedside monitor. So we compared the change in cardiac output derived from arterial pressure waveforms (pulse contour analysis) with that from carotid artery Doppler-derived measurements, in post-major elective abdominal surgery patients. Materials and methods We conducted a prospective observational study in 30 adult post-major elective abdominal surgery patients admitted to the Gastroenterology and Liver Transplant intensive care unit postoperatively on mechanical ventilator support, who were found to be fluid responsive clinically on passive leg raise (PLR) test. Demographics and vasopressor support were recorded. Hemodynamic parameters including heart rate, systolic blood pressure (SBP), diastolic blood pressure (DBP), cardiac output (CO) using arterial pulse contour analysis (Vigileo monitor/FloTrac® sensor; Edwards Lifesciences, Irvine, California, United States), and carotid blood flow (CBF) were recorded on the baseline, pre- and post- PLR, and post fluid bolus administration. Balanced salt solution at the rate of 6ml/kg over 20 minutes was given as a fluid bolus. Results Of the 30 patients who were included in the study, 16 patients (53.3%) were on vasopressor support, mean (± SD) age of the patients was 52.93 (± 8.13) years. There was a significant increase in the SBP (mmHg) pre- to post-PLR, that is, 112.2±15.57 and 118.7±14.96, respectively (p-value = 0.001). Also from pre-PLR to post-fluid bolus administration, the increase in SBP was significant, 112.2±15.57 and 121.93±13.96, respectively (p-value = 0.001). The change in cardiac output measured using Vigileo and CBF from pre- to post-PLR (7.66±1.45 to 9.14±1.76, p< 0.001 for Vigileo and 8.10±1.66 to 9.72±1.99, p<0.001 for CBF) and pre-PLR to post fluid administration (7.66±1.45 to 9.39±1.77, p< 0.001 for Vigileo and 8.10±1.66 to 10.31±2.26, p< 0.001 for CBF) were significant. There was a positive correlation between the change in cardiac output as measured from arterial pulse contour analysis technique (Vigileo) and that measured from CBF (r=0.884) pre- and post-PLR. There was a significant correlation between cardiac output measurements derived from two techniques, before PLR, after PLR, and after fluid expansion (p< 0.001 for each variable). The change in cardiac output before PLR and after fluid expansion was also correlated by both the techniques (correlation coefficient being, r=0.781). Conclusion There was a significant positive correlation of the CO (absolute and change) measurements pre- and post-interventions (that is, PLR and fluid bolus administration) as made by pulse contour analysis (Vigileo) and by CBF in post-surgical patients. Pulse wave Doppler of CBF could be used as a surrogate for invasive measures of CO measurement for prediction of fluid responsiveness in this subgroup. Further larger studies can be performed to validate the same.

[Project to Improve FloTrac Cognition and Skill Accuracy in Nurses Working in the Intensive Care Unit].

BACKGROUND & PROBLEMS: FloTrac is used to monitor hemodynamics in patients. Insufficient awareness of and inexperience with this machine put patients at risk. PURPOSE: A project was developed to increase FloTrac cognitive accuracy from 57.6% to 85% and skill accuracy from 73.3% to 91% in ICU nurses. Also, FloTrac installation time was intended to be reduced to less than 8 minutes and 38 seconds. RESOLUTION: Create a pithy, easy-to-remember formula; make operation teaching videos, operation manuals, and reminder cards; arrange educational training; and monitor quality regularly. RESULTS: FloTrac cognitive accuracy increased from 57.6% to 90.4%; FloTrac skill accuracy increased from 73.3% to 99.7%; and installation time was shortened from 8 minutes and 38 seconds to 5 minutes and 42 seconds. CONCLUSIONS: After implementation of the project, nurses improved their professional knowledge and were better able to help doctors obtain hemodynamic data efficiently to provide patients with accurate and rapid treatment.

The influence of the Pringle maneuver in laparoscopic hepatectomy: continuous monitor of hemodynamic change can predict the perioperatively physiological reservation.

Importance: This is the first study to investigate the correlation between intra-operative hemodynamic changes and postoperative physiological status. Design settings and participants: Patients receiving laparoscopic hepatectomy were routinely monitored using FloTract for goal-directed fluid management. The Pringle maneuver was routinely performed during parenchymal dissection and the hemodynamic changes were prospectively recorded. We retrospectively analyzed the continuous hemodynamic data from FloTrac to compare with postoperative physiological outcomes. Exposure: The Pringle maneuver during laparoscopic hepatectomy. Results: Stroke volume variation that did not recover from the relief of the Pringle maneuver during the last application of Pringle maneuver predicted elevated postoperative MELD-Na scores. Conclusions and relevance: The complexity of the hemodynamic data recorded by the FloTrac system during the Pringle Maneuver in laparoscopic hepatectomy can be effectively analyzed using the growth mixture modeling (GMM) method. The results can potentially predict the risk of short-term liver function deterioration.

Current Commonly Used Dynamic Parameters and Monitoring Systems for Perioperative Goal-Directed Fluid Therapy: A Review.

Goal-directed fluid therapy (GDFT) is usually recommended in patients undergoing major surgery and is essential in enhanced recovery after surgery (ERAS) protocols. This fluid regimen is usually guided by dynamic hemodynamic parameters and aims to optimize patients' cardiac output to maximize oxygen delivery to their vital organs. While many studies have shown that GDFT benefits patients perioperatively and can decrease postoperative complications, there is no consensus on which dynamic hemodynamic parameters to guide GDFT with. Furthermore, there are many commercialized hemodynamic monitoring systems to measure these dynamic hemodynamic parameters, and each has its pros and cons. This review will discuss and review the commonly used GDFT dynamic hemodynamic parameters and hemodynamic monitoring systems.

Accuracy of Cardiac Output Measured by Fourth-Generation FloTrac and LiDCOrapid, and Their Characteristics Regarding Systemic Vascular Resistance in Patients Undergoing Cardiac Surgery.

OBJECTIVES: The clinical use of less-invasive devices that calculate the cardiac output from arterial pressure waveform is increasing. The authors aimed to evaluate the accuracy and characteristics of the systemic vascular resistance index (SVRI) of the cardiac index measured by 2 less-invasive devices, fourth-generation FloTrac (CIFT) and LiDCOrapid (CILR), compared with the intermittent thermodilution technique, using a pulmonary artery catheter (CITD). DESIGN: This was a prospective observational study. SETTING: This study was conducted at a single university hospital. PARTICIPANTS: Twenty-nine adult patients undergoing elective cardiac surgery. INTERVENTIONS: Elective cardiac surgery was used as an intervention. MEASUREMENTS AND MAIN RESULTS: Hemodynamic parameters, CIFT, CILR, and CITD, were measured after the induction of general anesthesia, at the start of cardiopulmonary bypass, after completion of weaning from cardiopulmonary bypass, 30 minutes after weaning, and at sternal closure (135 measurements in total). The CIFT and CILR had moderate correlations with CITD (r = 0.62 and 0.58, respectively). Compared with CITD, CIFT, and CILR had a bias of -0.73 and -0.61 L/min/m2, limit of agreement of -2.14-to-0.68 L/min/m2 and -2.42-to-1.20 L/min/m2, and percentage error of 39.9% and 51.2%, respectively. Subgroup analysis for evaluating SVRI characteristics showed that the percentage errors of CIFT and CILR were 33.9% and 54.5% in low SVRI (<1,200 dyne×s/cm5/m), 37.6% and 47.9% in moderate SVRI (1,200-1,800 dyne×s/cm5/m), 49.3% and 50.6% in high SVRI (>1,800 dyne·s/cm5/m2), respectively. CONCLUSIONS: The accuracy of CIFT or CILR was not clinically acceptable for cardiac surgery. Fourth-generation FloTrac was unreliable in high SVRI. LiDCOrapid was inaccurate across a broad range of SVRI, and minimally affected by SVRI.

What is the optimal anesthetic monitoring regarding immediate and short-term outcomes after liver transplantation?-A systematic review of the literature and expert panel recommendations.

BACKGROUND: Liver transplant centers vary in approach to intraoperative vascular accesses, monitoring of cardiac function and temperature management. Evidence is limited regarding impact of selected modalities on postoperative outcomes. OBJECTIVES: To review the literature and provide expert panel recommendations on optimal intraoperative arterial blood pressure (BP), central venous pressure (CVP), and vascular accesses, monitoring of cardiac function and intraoperative temperature management regarding immediate and short-term outcomes after orthotopic liver transplant (OLT). METHODS: Systematic review following PRISMA guidelines and recommendations using the GRADE approach derived from an international expert panel. Recommendations made for: (1) Vascular accesses, arterial BP and CVP monitoring, (2) cardiac function monitoring, and (3) Intraoperative temperature management (CRD42021239908). RESULTS: Of 2619 articles screened 16 were included. Studies were small, retrospective, and observational. Vascular access studies demonstrated low rates of insertion complications. TEE studies demonstrated low rates of esophageal hemorrhage. One study found lower hospital-LOS and 30-day mortality in patients monitored with both PAC and TEE. Other monitoring studies were heterogenous in design and outcomes. Temperature studies showed increased blood transfusion and ventilation times in hypothermic groups. CONCLUSIONS: Recommendations were made for; routine arterial and CVP monitoring as a minimum standard of practice, consideration of discrepancy between peripheral and central arterial BP in patients with hemodynamic instability and high vasopressor requirements, and routine use of high flow cannulae while monitoring for extravasation and hematoma formation. Availability and expertise in PAC and/or TEE monitoring is strongly recommended particularly in hemodynamic instability, portopulmonary HT and/or cardiac dysfunction. TEE use is recommended as an acceptable risk in patients with treated esophageal varices and is an effective diagnostic tool for emergency cardiovascular collapse. Maintenance of intraoperative normothermia is strongly recommended.

Relationship between pulse pressure variation and stroke volume variation with changes in cardiac index during hypotension in patients undergoing major spine surgeries in prone position - A prospective observational study.

Background and Aims: Dynamic indices such as pulse pressure variation (PPV) and stroke volume variation (SVV) are better predictors of fluid responsiveness than static indices. There is a strong correlation between PPV and SVV in the prone position when assessed with the fluid challenge. However, this correlation has not been established during intraoperative hypotension. Our study aimed to assess the correlation between PPV and SVV during hypotension in the prone position and its relationship with cardiac index (CI). Material and Methods: Thirty patients aged 18-70 years of ASA class I-III, undergoing spine procedures in the prone position were recruited for this prospective observational study. Hemodynamic variables such as heart rate (HR), mean arterial pressure (MAP), PPV, SVV, and CI were measured at baseline (after induction of anesthesia and positioning in the prone position). This set of variables were collected at the time of hypotension (T-before) and after correction (T-after) with either fluids or vasopressors. HR and MAP are presented as median with inter quartile range and compared by Mann-Whitney U test. Reliability was measured by intraclass correlation coefficients (ICC). Generalized estimating equations were performed to assess the change of CI with changes in PPV and SVV. Results: A statistically significant linear relationship between PPV and SVV was observed. The ICC between change in PPV and SVV during hypotension was 0.9143, and after the intervention was 0.9091 (P < 0.001). Regression of changes in PPV and SVV on changes in CI depicted the reciprocal change in CI which was not statistically significant. Conclusion: PPV is a reliable surrogate of SVV during intraoperative hypotension in the prone position.

Hemodynamic Monitoring Using a Pulmonary Artery Catheter Versus the Vigileo/FloTrac System during Elective Cardiac Surgery Based on Real-world Data in Japan.

BACKGROUND: The controversy concerning the benefits of pulmonary artery catheter (PAC)-based hemodynamic monitoring in cardiac surgeries has not been adequately addressed. This study aims to compare the all-cause mortality between the PAC with venous oxygen saturation monitoring and the Vigileo/FloTrac (FloTrac) system with central venous oxygen saturation monitoring in cardiac surgeries. METHODS: This nationwide retrospective study includes adult patients who underwent elective cardiac surgeries between April 2010 and October 2014, based on the Japanese health insurance claims database. The main outcome was 30-day all-cause mortality. Propensity scores (PS) were used to adjust for the confounding factors. Treatment effects were estimated using multivariable logistic regression analysis, including PS. RESULTS: A total of 5,838 patients were included in this study. The crude 30-day mortality rates were 2.4% (8/334) and 1.7% (96/5,504) in the FloTrac and PAC groups, respectively. After PS matching, the ORs for 30-day all-cause mortality, in-hospital mortality after PAC placement (vs. FloTrac) were 0.36 (95% CI: 0.05-2.37; p = 0.28) and 0.59 (95% CI: 0.16-2.20; p = 0.43), respectively. The amount of dobutamine was larger in the PAC group (281 ± 31 mg vs 155 ± 19 mg; p < 0.001). There were no significant differences in the amounts of other inotropes, the volume of fluids, or blood transfusions. CONCLUSIONS: The association between PAC (with venous oxygen saturation monitoring) and mortality in patients who underwent elective cardiac surgeries was unclear compared to FloTrac (with central venous oxygen saturation monitoring). Additional investigation is needed to evaluate the benefits of PAC-specific hemodynamic parameters in this population.

Comparison of accuracy of two uncalibrated pulse contour cardiac output monitors in off-pump coronary artery bypass surgery patients using pulmonary artery catheter-thermodilution as a reference.

BACKGROUND: Cardiac output (CO) is a key measure of adequacy of organ and tissue perfusion, especially in critically ill or complex surgical patients. CO monitoring technology continues to evolve. Recently developed CO monitors rely on unique algorithms based on pulse contour analysis of an arterial blood pressure (ABP) waveform. The objective of this investigation was to compare the accuracy of two monitors using different methods of pulse contour analysis - the Retia Argos device and the Edwards Vigileo-FloTrac device - with pulmonary artery catheter (PAC)-thermodilution as a reference. METHODS: Fifty-eight patients undergoing off-pump coronary artery bypass surgery formed the study cohort. A total of 572 triplets of CO measurements from each device - Argos, Vigileo-FloTrac (third generation), and thermodilution - were available before and after interventions (e.g., vasopressors, fluids, and inotropes). Bland-Altman analysis accounting for repeated measurements per subject and concordance analysis were applied to assess the accuracy of the CO values and intervention-induced CO changes of each pulse contour device against thermodilution. Cluster bootstrapping was employed to statistically compare the root-mean-squared-errors (RMSE = √(µ2 + σ2), where µ and σ are the Bland-Altman bias and precision errors) and concordance rates of the two devices. RESULTS: The RMSE (mean (95% confidence intervals)) for CO values was 1.16 (1.00-1.32) L/min for the Argos device and 1.54 (1.33-1.77) L/min for the Vigileo-FloTrac device; the concordance rate for intervention-induced CO changes was 87 (82-92)% for the Argos device and 72 (65-78)% for the Vigileo-FloTrac device; and the RMSE for the CO changes was 17 (15-19)% for the Argos device and 21 (19-23)% for the Vigileo-FloTrac device (p < 0.0167 for all comparisons). CONCLUSIONS: In comparison with CO measured by the PAC, the Argos device proved to be more accurate than the Vigileo-FloTrac device in CO trending and absolute CO measurement in patients undergoing off-pump coronary artery bypass surgery.

Intraoperative cardiac function assessment by transesophageal echocardiography versus FloTrac/Vigileo™ system during pectus excavatum surgical repair.

BACKGROUND: Pectus excavatum (PE), a congenital deformity of the chest wall, can lead to cardiac compression and related symptoms. PE surgical repair can improve cardiac function. Intraoperative transesophageal echocardiography (TEE) has been successfully employed to assess intraoperative hemodynamic variations in patients undergoing PE repair. FloTrac/Vigileo™ system (Edwards Life-sciences Irvine, CA) (FT/V) is a minimally invasive cardiac output monitoring system. This retrospective study aimed to assess hemodynamic changes in surgical repair of PE using FT/V and concordance with parameters measured by TEE. RESULTS: N=19 patients submitted to PE repair via Ravitch or Nuss technique were enrolled. Intraoperative cardiac assessments simultaneously obtained via TEE and FT/V system were investigated. The agreement between TEE-derived cardiac output (CO-TEE) and FT/V system parameter (COAP) was evaluated. The relationship between COTEE and COAP was analyzed for all data using linear regression analysis. A significant correlation between COAP and COTEE values (R = 0.65, p < 0.001) was found. Bland-Altman analysis of COAP and COTEE showed a bias of 0.13 L/min and a limit of agreement of - 2.33 to 2.58 L/min, with a percentage error of 48%. Intraoperative measurements by TEE and FT/V both showed a significant increase in CO after surgical correction of PE (p < 0.005). CONCLUSIONS: FT/V system compared to TEE in hemodynamic monitoring during PE surgery yielded clinically unacceptable results due to a high percentage error. After surgical correction of PE, CO, measured by TEE and FT/V, significantly improved.

Comparing the Mutual Interchangeability of ECOM, FloTrac/Vigileo, 3D-TEE, and ITD-PAC Cardiac Output Measuring Systems in Coronary Artery Bypass Grafting.

OBJECTIVE: The aim of this study was to compare the mutual interchangeability of 4 cardiac output measuring devices by comparing their accuracy, precision, and trending ability. DESIGN: A single-center prospective observational study. DESIGN: Nonuniversity teaching hospital, single center. PARTICIPANTS: Forty-four consecutive patients scheduled for elective, nonemergent coronary artery bypass grafting (CABG). INTERVENTIONS: The cardiac output was measured for each participant using 4 methods: intermittent thermodilution via pulmonary artery catheter (ITD-PAC), Endotracheal Cardiac Output Monitor (ECOM), FloTrac/Vigileo System (FLOTRAC), and 3-dimensional transesophageal echocardiography (3D-TEE). MEASUREMENTS AND MAIN RESULTS: Measurements were performed simultaneously at 5 time points: presternotomy, poststernotomy, before cardiopulmonary bypass, after cardiopulmonary bypass, and after sternal closure. A series of statistical and comparison analyses including ANOVA, Pearson correlation, Bland-Altman plots, quadrant plots, and polar plots were performed, and inherent precision for each method and percent errors for mutual interchangeability were calculated. For the 6 two-by-two comparisons of the methods, the Pearson correlation coefficients (r), the percentage errors (% error), and concordance ratios (CR) were as follows: ECOM_versus_ITD-PAC (r = 0.611, % error = 53%, CR = 75%); FLOTRAC_versus_ITD-PAC (r = 0.676, % error = 49%, CR = 77%); 3D-TEE versus ITD-PAC (r = 0.538, % error = 64%, CR = 67%); FLOTRAC_versus_ECOM (r = 0.627, % error = 51%, CR = 75%); 3D-TEE_versus ECOM (r = 0.423, % error = 70%, CR = 60%), and 3D-TEE_versus_FLOTRAC (r = 0.602, % error = 59%, CR = 61%). CONCLUSIONS: Based on the recommended statistical measures of interchangeability, ECOM, FLOTRAC, and 3D-TEE are not interchangeable with each other or to the reference standard invasive ITD-PAC method in patients undergoing nonemergent cardiac bypass surgery. Despite the negative result in this study and the majority of previous studies, these less-invasive methods of CO have continued to be used in the hemodynamic management of patients. Each device has its own distinct technical features and inherent limitations; it is clear that no single device can be used universally for all patients. Therefore, different methods or devices should be chosen based on individual patient conditions, including the degree of invasiveness, measurement performance, and the ability to provide real-time, continuous CO readings.

To compare intraoperative goal directed fluid therapy by trans-oesophageal Doppler vis-à-vis FloTrac™ in patients undergoing living related renal transplantation-a prospective randomised controlled study.

BACKGROUND: Optimal intra-operative fluid therapy in renal transplantation (RT) is essential to ensure adequate graft function while preventing fluid overload related complications. This RCT was to compare the intraoperative goal directed fluid therapy (GDFT) based either on corrected flow time (CFT), measured by trans oesophageal Doppler (TED) or on the stroke volume variation (SVV), by FloTrac in patients undergoing living donor RT. METHODS: This prospective, randomised controlled trial (RCT) was done on 60 end stage renal disease (ESRD) patients, American Society of Anaesthesiologists(ASA) grade III-IV, age 18 to 65 years of either sex, scheduled for living donor RT under general anaesthesia. They were randomly divided into two groups: TED group (n = 30) and FloTrac™ group (n = 30) and administered GDFT, based upon CFT (TED) and SVV (FloTrac™). The primary outcome was to compare the total fluid and number of fluid boluses administered intraoperatively, while the secondary outcomes were to compare any postoperative complications due to fluid overload and allograft function, assessed by serial serum creatinine levels up to 90 days postoperatively. RESULTS: The mean total intra-operative fluid [3991.67 ± 856.32 vs. 3543.33 ± 1131.35, P = 0.089] and the amount of fluid administered per kg body weight per hour [13.32 ± 4.67 vs. 11.82 ± 4.76, P = 0.222] were lesser in the FloTrac compared to TED group, though not statistically significant. However, the postoperative incidence of allograft dysfunction, including rejection (P = 0.743) and acute tubular necrosis (ATN) (P = 0.999), and other complications (P = 0.643) were comparable. CONCLUSIONS: Both TED and FloTrac devices can be used effectively to guide GDFT in RT, However, lesser total fluid was required in the FloTrac group, which may lead to a lesser number of fluid-related postoperative complications.

Postoperative hemodynamic changes for predicting anastomotic leakage after esophagectomy in patients with esophageal cancer using the FloTrac system.

Background : Anastomotic leakage after esophagectomy is significantly associated with more severe complications, such as sepsis and mortality. Early prediction for anastomotic leakage is usually difficult and needs to be treated rapidly. In the current study, we investigated the correlation between hemodynamic and several complications after esophagectomy in patients with esophageal cancer, using the FloTrac system. Materials and Methods : Between April 2013 and December 2014, 39 patients with a mean age of 66.6 ±â€…8.9 years underwent postoperative supervision using the FloTrac sensor / Vigileo monitoring system after curative surgery for esophageal cancer. We retrospectively evaluated the association between the number of aberrant cardiac index (CI) along with stroke volume variability (SVV) values and clinicopathological parameters of postoperative complications in this report. Results : There were significant positive correlations between the number of aberrant values of CI along with SVV and depth of invasion during pathological stage. Concerning major postoperative complications, there was a significant positive correlation between the number of aberrant values of CI and anastomotic leakage. Discussion: The hemodynamic change by employing the FloTrac system could predicts the complication of anastomotic leakage after esophagectomy. Adequate management of hemodynamic stability by utilizing it will reduce the complications of anastomotic leakage. J. Med. Invest. 67 : 240-245, August, 2020.

Surgical Field Visualization during Functional Endoscopic Sinus Surgery: Comparison of Propofol- vs Desflurane-Based Anesthesia.

OBJECTIVE: To assess if the type of general anesthetic affects bleeding and field visualization during endoscopic sinus surgery. STUDY DESIGN: Prospective, randomized, controlled trial. SETTING: Academic teaching hospital and Veterans Affairs hospital in the United States. SUBJECTS AND METHODS: Seventy patients were randomized to 1 of 3 anesthetic regimens: (1) the volatile anesthetic desflurane (n = 22), (2) intravenous anesthesia with propofol (n = 25), or (3) a combination of propofol and desflurane (n = 23). Intravenous remifentanil was titrated to decrease the mean arterial pressure to 60 to 70 mm Hg but not ≥30% from baseline. Surgical bleeding scores were recorded along with bleeding rates and hemodynamic parameters, including cardiac output and systemic vascular resistance through pulse contour analysis from a radial arterial line. Statistics: multiple comparison tests and regression analyses; α = .05. RESULTS: There were no differences in bleeding rate (median, 0.58, 0.85, 0.57 mL min-1), bleeding score (2.1, 2.0, 2.0), surgery duration (79, 81, 86 minutes), extubation time (9, 7, 8 minutes), recovery room time (65, 61, 61 minutes), or any hemodynamic parameters among groups 1 through 3, respectively. Group 1 required lower remifentanil infusions than group 2 (0.11 vs 0.26 µg kg-1 min-1; P = .01). The bleeding score correlated positively with height (P = .014) and the Lund-MacKay score (P = .013). Bilateral vs unilateral surgery led to longer surgery duration (P = .001) and recovery room time (P = .004). CONCLUSION: When remifentanil is used for controlled hypotension, propofol has no advantage over desflurane to improve surgical field visualization during functional endoscopic sinus surgery.

The association between arterial pulse waveform analysis device and in-hospital mortality in high-risk non-cardiac surgeries.

BACKGROUND: Perioperative goal-directed fluid therapy is used for haemodynamic optimization in high-risk surgeries. Cardiac output monitoring can be performed by a specialized pressure transducer for arterial pulse waveform analysis (S-APWA). No study has assessed whether real-world use of S-APWA is associated with post-operative outcomes; therefore, using a Japanese administrative claims database, we retrospectively investigated whether S-APWA use is associated with in-hospital mortality among patients undergoing high-risk surgery under general anaesthesia. METHODS: Adult patients who underwent high-risk surgery under general anaesthesia and arterial catheterization between 2014 and 2016 were divided into S-APWA and conventional arterial pressure transducer groups, then compared regarding baseline factors and outcomes. Logistic regression analysis was performed to compare in-hospital mortality. Subgroup analyses evaluated S-APWA efficacy and outcomes based on the type of surgery and patients' comorbidity. RESULTS: S-APWA was used in 6859 of 23 655 (29.0%) patients; the crude in-hospital mortality rate was 3.5%. Adjusted analysis showed no significant association between S-APWA use and in-hospital mortality rate (adjusted odds ratio [aOR] = 0.91; 95% confidence interval [CI]: 0.76-1.07; P = .25). S-APWA use was associated with significantly lower in-hospital mortality in patients undergoing vascular surgery (aOR = 0.67; 95% CI: 0.49-0.94), and significantly higher in-hospital mortality in patients undergoing lower limb amputation (aOR = 2.63; 95% CI: 1.32-5.22). S-APWA use and in-hospital mortality were not significantly associated with other subgroups. CONCLUSION: S-APWA use was not associated with in-hospital mortality in the entire study population. However, S-APWA was associated with decreased in-hospital mortality among vascular surgery and increased in-hospital mortality among lower limb amputation.

Hemodynamic Changes During Surgical Decompression in Traumatic Brain Injury Patients.

OBJECTIVE: To understand the hemodynamic changes that occur with surgical decompression of lesions caused by traumatic brain injury. METHODS: In this prospective, observational study, patients with traumatic brain injury requiring craniotomy within 48 hours of injury were recruited. Cardiac index (CI), stroke volume index, stroke volume variation, systemic vascular resistance index (SVRI), heart rate, and mean arterial pressure were monitored throughout surgery using a FloTrac transducer. Standard anesthetic and surgical regimens were followed. RESULTS: Hemodynamic data in 107 patients were compared before skin incision and after hematoma decompression (comparable anesthetic state). There was a significant increase in CI and stroke volume index and a decrease in SVRI and mean arterial pressure following surgical decompression. On subgroup analysis based on preincision CI, the changes were similar in patients with low and normal CI, whereas in patients with high CI, SVRI did not decrease significantly. High preincision CI with no change in SVRI with decompression was associated with poor neurologic outcome at discharge. CONCLUSIONS: In patients with TBI, surgical decompression leads to an increase in CI and a decrease in mean arterial pressure owing to a decrease in SVRI in patients with preincision low or normal cardiac output. These changes were not seen in patients with preincision high CI, and such patients had a poor neurologic outcome.

Evaluation of Surgical Procedures that Affect the Hemodynamics Using the FloTrac System in Esophageal Cancer Patients.

BACKGROUND/AIM: Esophagectomy is more invasive compared to other gastrointestinal surgery types. Perioperative circulatory management is important to avoid postoperative heart complications. The FloTrac sensor along with the Vigileo monitor is a minimally invasive haemodynamic monitoring device. Here, we examined different surgical procedures affecting hemodynamics using the FloTrac system in esophageal cancer patients following esophagectomy. PATIENTS AND METHODS: Thirty-one patients undergoing postoperative monitoring with the FloTrac sensor/Vigileo monitor system following esophagectomy were included. Evaluation of cardiac index (CI) and stroke volume variation (SVV) measurements were performed by analyzing the number of aberrant values. We evaluated the correlation between the number of aberrant values of CI, SVV and surgical methods of esophagectomy and perioperative factors. RESULTS: There was no significant correlation between the number of aberrant values of CI, SVV and operative approach or fields of lymphadenectomy. Regarding the reconstruction route following esophagectomy, there was a significant correlation between the number of aberrant values of CI, SVV and retrosternal route compared with other routes. There was a significant correlation between the number of aberrant values of SVV and preoperative heart complication. CONCLUSION: Hemodynamic stability management using FloTrac/Vigileo system following esophagectomy is useful for safe performance of postoperative management of esophageal cancer patients.

Utilization of arterial pulse waveform analysis during non-cardiac surgery in Japan: a retrospective observational study using a nationwide claims database.

Arterial pulse waveform analysis (APWA) is used for cardiac output monitoring. However, data on the frequency of and patient characteristics for specialized pressure transducer for APWA (S-APWA) use are lacking. We retrospectively identified 175,201 patients aged 18 years or older, who underwent non-cardiac surgery under general anesthesia with an arterial catheter from January 1, 2014, to December 31, 2016. We extracted data on patient demographics, comorbidities, surgical and anesthesia characteristics, and hospital characteristics. Among the full study cohort, 24,605 (14.0%) patients were monitored using S-APWA. Further, the use of S-APWA was higher in patients undergoing high-risk surgery than in those undergoing low-risk surgery [high vs low: adjusted odds ratio (aOR) 1.95; 95% confidence interval (CI) 1.76-2.15, moderate vs low: aOR 1.11; 95% CI 1.01-1.22] and those with more comorbidities than in those with less comorbidities (high vs low: aOR 1.49; 95% CI 1.42-1.56, moderate vs low: aOR 1.25; 95% CI 1.20-1.31). S-APWA use was significantly associated with both surgery risk and patients' comorbidities. In conclusion, our study may provide a benchmark for future studies related to the appropriate use of S-APWA.

Evaluation of the Fourth-Generation FloTrac/Vigileo System in Comparison With the Intermittent Bolus Thermodilution Method in Patients Undergoing Cardiac Surgery.

OBJECTIVES: The aim of this study was to evaluate the accuracy, precision, and trending ability of the fourth-generation FloTrac/Vigileo system (version 4.00; Edwards Lifesciences, Irvine, CA) by comparing cardiac output derived from FloTrac/Vigileo system (COAP) with that measured by a pulmonary artery catheter (COTD), and to determine the effects of hemodynamic variables on the bias between COTD and COAP. DESIGN: A prospective study. SETTING: University hospital. PARTICIPANTS: Thirty patients undergoing elective cardiac surgery using cardiopulmonary bypass. INTERVENTIONS: Including hemodynamic variables, COTD and COAP were measured simultaneously at the following 10 time points: after the induction of anesthesia, at the start of operation, after sternotomy, before and after the administration of heparin, before and after the administration of protamine, at the start of sternal closure, at the end of operation, and on arrival to intensive care unit. MEASUREMENTS AND MAIN RESULTS: In total, 280 pairs of datasets were obtained. Bland-Altman analysis showed a bias of -0.41 L/min, a precision of 0.72 L/min, and limits of agreement of -1.85 and 1.03 L/min, with a percentage error of 37.1%. The concordance rate determined by 4-quadrant plot analysis and the polar concordance rate were 76% and 79%, respectively. The linear mixed-effect model revealed that the bias was influenced strongly by the difference in pulse pressure between the radial and femoral artery (p < 0.001), and the systemic vascular resistance index (p < 0.001). CONCLUSION: The fourth-generation FloTrac/Vigileo system still lacks accuracy and trending ability in cardiac surgery, and the discrepancy in cardiac output measurement depends on the peripheral vascular tone. Further improvement of this system is needed.

Clinical Applications of Goal-Directed Fluid Therapy for Pancreatoduodenectomy / 中国医科大学学报

Objective To investigate the clinical applications of goal-directed fluid therapy for pancreatoduodenectomy. Methods A total of 40 patients undergoing pancreatoduodenectomy under general anesthesia were randomly divided into two groups, G and C, with 20 cases in each group. Goal-directed fluid therapy was used in Group G, whereas conventional fluid therapy was used in group C. The intraoperative hemodynamics, liquid management, duration of the first postoperative gastrointestinal ventilation, postoperative renal function, serum lactate, and the incidence of postoperative complications were recorded. Results Compared with group C, the CI increased and SVV decreased (P ＜ 0.05) at T3 to T5, and MAP increased at T4 to T5 (P ＜ 0.05). The amount of fluid infusion and total infusion in group G were less than that of group C (P ＜ 0.05), and the number of vasoactive drugs was greater than that of group C (P ＜ 0.05). The duration of the first postoperative gastrointestinal ventilation in group G was shorter than that of group C (P ＜ 0.05). There were no significant differences between the 2 groups for the incidence of serum lactate, BUN, Cr, and the incidence of postoperative complications (P＞ 0.05).Conclusion For major complex operations, such as pancreaticoduodenectomy, goal-directed fluid therapy can guide intraoperative fluid therapy more accurately with individual optimizations, and has more advantages in maintaining intraoperative hemodynamics stability and improving postoperative outcome.