Intra-arterial Blood Pressure Measurements Research Articles

Comparison of forearm and intra-arterial blood pressure measurements according to body and arm positions in obese patients.

Noninvasive blood pressure (BP) monitoring is very important also difficult for accurate diagnosis and monitor of obese patients. The study aimed to assess the agreement between forearm arm BP and intra-arterial BP values in a different body and arm positions in obese patients. The descriptive study was carried out on 60 intensive care patients with a body mass index above 30 kg/m2 who were monitored with invasive radial BP in the general and surgical intensive care units. BP values obtained from the upper arm and forearm with different arm and body positions were compared with intra-arterial BP results. Bland-Altman analysis and correlation coefficient were used for the accuracy of upper and forearm noninvasive BP reading in different positions. The best agreement was found between the forearm systolic BP in the supine and half-sitting position with the arm down and intra-arterial BP values. Also, the best agreement in diastolic BP was found between the half-sitting and half-sitting position with the arm down and intra-arterial BP. Forearm systolic BP measurement, especially in the supine and half-sitting position with the arm below the heart level position, was best agreement with intra-arterial measurement, regarded as the gold standard. For this reason, it is more appropriate to use forearm BP measurement in obese patients monitored in intensive care to obtain accurate results.

Validation of oscillometric ratio and maximum gradient methods for non-invasive blood pressure measurement with intra-arterial blood pressure measurements as reference.

Most non-invasive blood pressure (BP) measurements are carried out using instruments which implement either the Ratio or the Maximum Gradient oscillometric method, mostly during cuff deflation, but more rarely during cuff inflation. Yet, there is little published literature on the relative advantages and accuracy of these two methods. In this study of 40 lightly sedated individuals aged 64.1 ± 9.6 years, we evaluate and compare the performance of the oscillometric ratio (K) and gradient (Grad) methods for the non-invasive estimation of mean pressure, SBP and DBP with reference to invasive intra-arterial values. There was no significant difference between intra-arterial estimates of mean pressure made via Korotkoff sounds (MP-OWE) or the gradient method (MP-Grad). However, 17.7% of MP-OWE and 15% of MP-Grad were in error by more than 10 mmHg. SBP-K and SBP-Grad underestimated SBP by 14 and 18 mmHg, whilst accurately estimating DBP with mean errors of 0.4 ± 5.0 and 1.7 ± 6.1 mmHg, respectively. Relative to the reference standard SBP-K, SBP-Grad and DBP-Grad were estimated with a mean error of -4.5 ± 6.6 and 1.4 ± 5.6 mmHg, respectively, noting that using the full range of recommended ratios introduces errors of 12 and 7 mmHg in SBP and DBP, respectively. We also show that it is possible to find ratios which minimize the root mean square error (RMSE) and the mean error for any particular individual cohort. We developed linear models for estimating SBP and SBP-K from a range of demographic and non-invasive OWE variables with resulting mean errors of 0.15 ± 5.6 and 0.3 ± 5.7 mmHg, acceptable according to the Universal standard.

Comparison of cuff inflation and cuff deflation brachial sphygmomanometry with intra-arterial blood pressure as reference.

Conventional sphygmomanometry with cuff deflation is used to calibrate all noninvasive BP (NIBP) instruments and the International Standard makes no mention of calibrating methods specifically for NIBP instruments, which estimate systolic and diastolic pressure during cuff inflation rather than cuff deflation. There is however increasing interest in inflation-based NIBP (iNIBP) instruments on the basis of shorter measurement time, reduction in maximal inflation pressure and improvement in patient comfort and outcomes. However, we have previously demonstrated that SBP estimates based on the occurrence of the first K1 Korotkoff sounds during cuff deflation can underestimate intra-arterial SBP (IA-SBP) by an average of 14 ± 10 mmHg. In this study, we compare the dynamics of intra-arterial blood pressure (IABP) measurements with sequential measurement of Korotkoff sounds during both cuff inflation and cuff deflation in the same individual. In 40 individuals aged 64.1 ± 9.6 years (range 36-86 years), the overall dynamic responses below the cuff were similar, but the underestimation error was significantly larger during inflation than deflation, increasing from 14 ± 10 to 19 ± 12 mmHg ( P < 0.0001). No statistical models were found which could compensate for this error as were found for cuff deflation. The statistically significant BP differences between inflation and deflation protocols reported in this study suggest different behaviour of the arterial and venous vasculature between arterial opening and closing which warrant further investigation, particularly for iNIBP devices reporting estimates during cuff inflation. In addition, measuring Korotkoff sounds during cuff inflation represents significant technical difficulties because of increasing pump motor noise.

Comparison of Intraarterial and Oscillometric Blood Pressure Measurement in Premature Newborns and Determination of Factors Affecting the Comparison

Comparison of Intraarterial and Oscillometric Blood Pressure Measurement in Premature Newborns and Determination of Factors Affecting the Comparison

A new noninvasive finger sensor (NICCI system) for continuous blood pressure and pulse pressure variation monitoring: A method comparison study in patients having neurosurgery.

The NICCI system (Getinge, Gothenburg, Sweden) is a new noninvasive haemodynamic monitoring system using a finger sensor. We aimed to investigate the performance of the NICCI system to measure blood pressure and pulse pressure variation compared with intra-arterial measurements. A prospective method comparison study. University Medical Center Hamburg-Eppendorf, Hamburg, Germany. Forty-seven neurosurgery patients. We performed a method comparison study in 47 neurosurgery patients to compare NICCI blood pressure measurements (BP NICCI ) with intra-arterial blood pressure measurements (BP ART ) (Bland-Altman analysis, four-quadrant plot, error grid analysis) and NICCI pulse pressure variation measurements (PPV NICCI ) with pulse pressure variation calculated manually from the intra-arterial blood pressure waveform (PPV ART ) (Bland-Altman analysis, predictive agreement, Cohen's kappa). The mean of the differences ± standard deviation (95% limits of agreement) between BP NICCI and BP ART was 11 ± 10 mmHg (-8 to 30 mmHg) for mean blood pressure (MBP), 3 ± 12 mmHg (-21 to 26 mmHg) for systolic blood pressure (SBP) and 12 ± 10 mmHg (-8 to 31 mmHg) for diastolic blood pressure (DBP). In error grid analysis, 54% of BP NICCI and BP ART MBP measurement pairs were classified as 'no risk', 43% as 'low risk', 3% as 'moderate risk' and 0% as 'significant risk' or 'dangerous risk'. The mean of the differences between PPV NICCI and PPV ART was 1 ± 3% (-4 to 6%). The predictive agreement between PPV NICCI and PPV ART was 80% and Cohen's kappa was 0.55. The absolute agreement between BP NICCI and BP ART was not clinically acceptable. We recommend not using the current version of the NICCI system for blood pressure monitoring during surgery. The absolute agreement between PPV NICCI and PPV ART was clinically acceptable with moderate predictive agreement regarding pulse pressure variation categories. The NICCI system needs to be further developed and re-evaluated when an improved version is available. The study was registered in the German Clinical Trials Register (DRKS00023188) on 2 October 2020.

Validity and success rate of noninvasive mean arterial blood pressure measurements in cf-LVAD patients: A technical review.

The life expectancy of patients with a continuous flow left ventricular assist device (cf-LVAD) is increasing. Adequate determination and regulation of mean arterial pressure (MAP) is important to prevent adverse events. Given the low pulsatility characteristics in these patients, standard blood pressure equipment is inadequate to monitor MAP and not recommended. We provide an overview of currently available noninvasive techniques, using an extensive search strategy in three online databases (Pubmed, Scopus and Google Scholar) to find validation studies using invasive intra-arterial blood pressure measurement as a reference. Mean differences with the reference values smaller than 5 ± 8 mm Hg were considered acceptable. After deduplication, screening, and exclusion of incorrect sources, eleven studies remained with 3139 successful MAP measurements in 386 patients. Four noninvasive techniques, using Doppler, pulse oximetry, finger cuff volume clamp, or slow upper arm cuff deflation, were identified and evaluated for validity and success rate in cf-LVAD patients. Here, a comprehensive technical background of the blood pressure measurement methods is provided in combination with a clinical use comparison. Of the reported noninvasive techniques, slow cuff devices performed most optimally (mean difference 1.3 ± 5.2 mm Hg). Our results are encouraging and indicate that noninvasive blood pressure monitoring options with acceptable validity and success rate are available. Further technical development and validation is warranted for the growing population of patients on long-term cf-LVAD support.

Intra-arterial blood pressure measurement: sources of error and solutions.

Intra-arterial blood pressure measurement is the cornerstone of hemodynamic monitoring in intensive care units (ICU). Accuracy of the measurement is dependent on the dynamic response of the measuring system, defined by its natural frequency (fnatural) and damping coefficient (Zdamping). Gardner's plot (1981) has long been the only way to determine the accuracy of the pressure measurement. Specific objectives: (i) estimation of the amplitude of error in pressure measurement through simulations based on real-world data, (ii) a novel method to correct the error. Simulated blood pressure waveforms of various heart rates were passed through simulated measurement systems with varying fnatural and Zdamping. The numerical errors in systolic and diastolic pressures and mean error in the measured pressure were used to generate heat maps for the various recording conditions, in the same plot as that by Gardner (1981). fnatural and Zdamping from 121 patient recordings are plotted on these heat maps to demonstrate the fraction of unacceptable recordings. Performance of a tunable filter to correct the error is demonstrated. In many clinical settings, the measurement of intra-arterial pressure is prone to significant error. The proposed tunable filter is shown to improve the accuracy of intra-arterial pressure recording.

Blood Pressure in Critically Ill Children: Exploratory Analyses of Concurrent Invasive and Noninvasive Measurements.

Differences and biases between directly measured intra-arterial blood pressure and intermittingly measured noninvasive blood pressure using an oscillometric cuff method have been reported in adults and children. At the bedside, clinicians are required to assign a confidence to a specific blood pressure measurement before acting upon it, and this is challenging when there is discordance between measurement techniques. We hypothesized that big data could define and quantify the relationship between noninvasive blood pressure and intra-arterial blood pressure measurements and how they can be influenced by patient characteristics, thereby aiding bedside decision-making. A retrospective analysis of cuff blood pressure readings with associated concurrent invasive arterial blood pressure measurements (452,195 noninvasive blood pressure measurements). Critical care unit at The Hospital for Sick Children, Toronto. Six-thousand two-hundred ninety-seven patients less than or equal to 18 years old, hospitalized in a critical care unit with an indwelling arterial line. None. Two-dimensional distributions of intra-arterial blood pressure and noninvasive blood pressure were generated and the conditional distributions of intra-arterial blood pressure examined as a function of the noninvasive systolic, diastolic, or mean blood pressure. Modification of these distributions according to age and gender were examined using a multilevel mixed-effects model. For any given combination of patient age and noninvasive blood pressure, the expected distribution of intra-arterial blood pressure readings exhibited marked variability at the population level and a bias that significantly depended on the noninvasive blood pressure value and age. We developed an online tool that allows exploration of the relationship between noninvasive blood pressure and intra-arterial blood pressure and the conditional probability distributions according to age. A large physiologic dataset provides clinically applicable insights into the relationship between noninvasive blood pressure and intra-arterial blood pressure measurements that can help guide decision-making at the patient bedside.

Comparison of Noninvasive Oscillometric and Intra-Arterial Blood Pressure Measurements in Children Admitted to the Pediatric Intensive Care Unit.

Intra-arterial blood pressure (IABP) measurement, although considered the gold standard in critically ill children, is associated with certain risks and lacks widespread availability. This study was conducted to determine the differences and agreements between oscillometric non-invasive blood pressure (NIBP) and invasive IABP measurements in children. Inclusion criteria consisted of children (from 1 month to 18 years) admitted to the pediatric intensive care unit (PICU) of a teaching hospital who required arterial catheter insertion for blood pressure (BP) monitoring. The comparison between IABP and NIBP was studied using paired t -test, Bland-Altman analysis, and Pearson's correlation coefficient. In total, 4,447 pairs of simultaneously recorded hourly NIBP and IABP measurements were collected from 65 children. Mean differences between IABP and NIBP were -3.6 ± 12.85, -4.7 ± 9.3, and -3.12 ± 9.30 mm Hg for systolic, diastolic, and mean arterial BP, respectively ( p < 0.001), with wide limits of agreement. NIBP significantly overestimated BP ( p < 0.001) in all three BP states (hypotensive, normotensive, and hypertensive), except systolic blood pressure (SBP) during hypertension where IABP was significantly higher. The difference in SBP was most pronounced during hypotension. The difference in SBP was significant in children <10 years ( p < 0.001), with the maximum difference being in infants. It was insignificant in adolescents ( p = 0.28) and underweight children ( p = 0.55). NIBP recorded significantly higher BP in all states of BP except SBP in the hypertensive state. SBP measured by NIBP tended to be the most reliable in adolescents and underweight children. NIBP was the most unreliable in infants, obese children, and during hypotension.

Perioperative Hemodynamic Monitoring: An Overview of Current Methods.

Perioperative hemodynamic monitoring is an essential part of anesthetic care. In this review, we aim to give an overview of methods currently used in the clinical routine and experimental methods under development. The technical aspects of the mentioned methods are discussed briefly. This review includes methods to monitor blood pressures, for example, arterial pressure, mean systemic filling pressure and central venous pressure, and volumes, for example, global end-diastolic volume (GEDV) and extravascular lung water. In addition, monitoring blood flow (cardiac output) and fluid responsiveness (preload) will be discussed.

Intraoperative Invasive Blood Pressure Monitoring and the Potential Pitfalls of Invasively Measured Systolic Blood Pressure.

Invasive intraarterial blood pressure measurement is currently the gold standard for intraoperative hemodynamic monitoring but accurate systolic blood pressure (SBP) measurement is difficult in everyday clinical practice, mostly because of problems with hyper-resonance or damping within the measurement system, which can lead to erroneous treatment decisions if these phenomena are not recognized. A hyper-resonant blood pressure trace significantly overestimates true systolic blood pressure while underestimating the diastolic pressure. Invasively measured systolic blood pressure is also significantly more affected than mean blood pressure by the site of measurement within the arterial system. Patients in the intraoperative period should be treated based on the invasively measured mean blood pressure rather than the systolic blood pressure. In this review, we discuss the pros/cons, mechanisms of invasive blood pressure measurements, and the interpretation of the invasively measured systolic blood pressure value.

Innovation in measuring obese patients' blood pressure: measurement with conical wrapping technique.

Accurate measurement of blood pressure (BP) is difficult in obese patients due to their upper arm shape and width. Errors made during BP measurement cause misdiagnosis or lead to wrong treatment. The data of this methodological study were collected from 40 patients who were 18 years old or above, with a BMI above 25 kg/m2, and who were followed up with radial catheter arterial pressure in adult intensive care and postoperative care units between March and December 2020. In total 55% of the participants were male with a mean age of 63.9 years, mean height of 165.7 cm, mean weight of 85.2 kg and mean BMI of 31.0 ± 2.1 kg/m2. Intra-arterial BP (IABP) measurement values were found to be correlated with conical wrapping technique and cylindrical wrapping technique (P < 0.001). As a result, a statistically significance was found between conical SBP and intra-arterial SBP (r = 0.921; P < 0.05) and conical DBP and intra-arterial DBP (r = 0.902; P < 0.05). It was determined that the SBP and DBP results of the conical wrapping technique were closer to the results obtained by IABP measurements. For this reason, it is more appropriate to measure BP with conical wrapping technique in clinically obese patients.

Intra-arterial versus oscillometric blood pressure measurements in women with severe peripartum hypertension undergoing urgent treatment with nicardipine: An observational study.

The aim of this study was to compare radial arterial catheter-derived pressure with oscillometric blood pressure in women with severe peripartum hypertension undergoing urgent treatment with intravenous nicardipine at a maternal intensive care unit. We obtained patients' paired values of systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP). All of the measurements were divided into four groups based on the levels of SBP and MAP measured using the oscillometric method. We assessed agreements of the paired values using the Bland-Altman method. The clinical relevance of differences between the two methods was assessed by error grid analysis. A total of 337 paired SBP and DBP values and 305 paired MAP values were obtained for 89 patients. The values of intra-arterial SBP were higher than those of oscillometric SBP. The values of intra-arterial MAP were higher than those of oscillometric MAP except for the women with MAP≥125mm Hg. Bland - Altman analysis showed acceptable agreement for DBP and MAP measured by intra-arterial method and oscillometric method. Error grid analysis showed the proportions of measurements in risk zones A to E were 83.22%, 16.46%, 0.32%, 0%, and 0% for SBP, and 97.81%, 2.19%, 0%, 0%, and 0% for MAP, respectively. Intra-arterial MAP can be used reliably to monitor the effect of intravenous nicardipine for treating severe hypertension. Intra-arterial SBP may trigger moderate-risk treatment decisions in the women with oscillometric SBP≤160mm Hg.

This Month in Anesthesiology

This Month in Anesthesiology

Intraoperative Blood Pressure Monitoring in Obese Patients.

The optimal method for blood pressure monitoring in obese surgical patients remains unknown. Arterial catheters can cause potential complications, and noninvasive oscillometry provides only intermittent values. Finger cuff methods allow continuous noninvasive monitoring. The authors tested the hypothesis that the agreement between finger cuff and intraarterial measurements is better than the agreement between oscillometric and intraarterial measurements. This prospective study compared intraarterial (reference method), finger cuff, and oscillometric (upper arm, forearm, and lower leg) blood pressure measurements in 90 obese patients having bariatric surgery using Bland-Altman analysis, four-quadrant plot and concordance analysis (to assess the ability of monitoring methods to follow blood pressure changes), and error grid analysis (to describe the clinical relevance of measurement differences). The difference (mean ± SD) between finger cuff and intraarterial measurements was -1 mmHg (± 11 mmHg) for mean arterial pressure, -7 mmHg (± 14 mmHg) for systolic blood pressure, and 0 mmHg (± 11 mmHg) for diastolic blood pressure. Concordance between changes in finger cuff and intraarterial measurements was 88% (mean arterial pressure), 85% (systolic blood pressure), and 81% (diastolic blood pressure). In error grid analysis comparing finger cuff and intraarterial measurements, the proportions of measurements in risk zones A to E were 77.1%, 21.6%, 0.9%, 0.4%, and 0.0% for mean arterial pressure, respectively, and 89.5%, 9.8%, 0.2%, 0.4%, and 0.2%, respectively, for systolic blood pressure. For mean arterial pressure and diastolic blood pressure, absolute agreement and trending agreement between finger cuff and intraarterial measurements were better than between oscillometric (at each of the three measurement sites) and intraarterial measurements. Forearm performed better than upper arm and lower leg monitoring with regard to absolute agreement and trending agreement with intraarterial monitoring. The agreement between finger cuff and intraarterial measurements was better than the agreement between oscillometric and intraarterial measurements for mean arterial pressure and diastolic blood pressure in obese patients during surgery. Forearm oscillometry exhibits better measurement performance than upper arm or lower leg oscillometry.

Comparing oscillometric noninvasive and invasive intra-arterial blood pressure monitoring in term neonates under general anesthesia: A retrospective study.

Oscillometric noninvasive blood pressure and/or invasive intra-arterial blood pressure are commonly used to measure the systolic, diastolic, and mean components of blood pressure. Agreement between the two methods has been reported in adults, children, and infants, but rarely in neonates, especially under general anesthesia. This retrospective study compared the agreement of each measured blood pressure value (oscillometric noninvasive or invasive intra-arterial blood pressure monitoring) in term neonates under general anesthesia. Data were collected from neonates born at ≥36weeks of gestation whose body weight was ≥2500g and who underwent abdominal or noncardiac thoracic surgery with both oscillometric noninvasive and invasive intra-arterial blood pressure measurements from January 2015 to March 2020. The primary outcome was the agreement of systolic, diastolic, and mean blood pressure values between the two methods using Bland-Altman analysis. Paired blood pressure measurements (n=1193) from 67 cases were compared. In Bland-Altman analysis, bias (standard deviation), 95% limits of agreement, and percentage error were -9.3 (8.4), -26.1-7.6, and 26.9% for systolic; 1.6 (6.5), -11.3-14.6, and 38.7% for diastolic; and -1.3 (5.8), -13.0-10.3, and 26.9% for mean blood pressure, respectively. During low blood pressure (intra-arterial mean blood pressure ≤30mmHg), the biases (standard deviation) of systolic, diastolic, and mean blood pressure were -11.4 (5.7), -0.7 (3.7), and -5.1 (4.2), whereas during high blood pressure (intra-arterial mean blood pressure ≥60mmHg), the values were 0.1 (9.7), 5.6 (9.4), and 6.4 (7.4), respectively. Based on the bias and percentage error, the mean blood pressure exhibited the most acceptable agreement between oscillometric noninvasive and invasive intra-arterial blood pressure monitoring in term neonates under general anesthesia. However, during hypertension or hypotension, there was a large discrepancy between the two methods.

Noninvasive measurement of arterial blood pressure in patients with continuous-flow left ventricular assist devices: a systematic review.

Accurate mean blood pressure determination is essential to prevent adverse events in patients with continuous-flow left ventricular assist devices (CFLVAD). We sought to evaluate the accuracy of noninvasive methods of blood pressure measurement compared with invasive intra-arterial recordings in patients with CFLVAD. Systematic electronic search was performed on four online databases (PubMed, Scopus, Embase, and Web of Knowledge) for the terms "Blood Pressure" AND ("Heart-Assist Devices" OR "Left ventricular Assist Devices"). Only studies that compared an intra-arterial and noninvasive blood pressure measurement were included. Electronic search of scientific literature identified 5968 articles. After deduplication, screening of titles and abstracts, full-text review, and excluding incorrect populations and comparator, a total of 12 studies with 502 participants were included, of those 402 participants who had intra-arterial blood pressure measurement. Doppler mean arterial blood pressure showed a very high correlation with mean intra-arterial blood pressure (r = 0.97, r = 0.87) in low pulsatility situations. When the pulsatility was not evaluated, the correlation was high moderate (r = 0.63, r = 0.741). In low pulsatility situations, the correlation was moderate to high moderate (r = 0.42 to r = 0.65). Oscillometer automatic blood pressure cuff showed a moderate to very high correlation with intra-arterial mean arterial blood pressure (r = 0.42, r = 0.86) but also could be low in the context of low pulsatility associated with inconsistent success in noninvasive measurement (r = 0.25). Studies correlating intra-arterial with noninvasive techniques were performed in the context of routine clinical care using fluid-filled catheters. The degree of correlation between both methods is at least moderate.

Brain Death Induction in Mice Using Intra-Arterial Blood Pressure Monitoring and Ventilation via Tracheostomy.

While both living donation and donation after circulatory death provide alternative opportunities for organ transplantation, donation after donor brain death (BD) still represents the major source for solid transplants. Unfortunately, the irreversible loss of brain function is known to induce multiple pathophysiological changes, including hemodynamic as well as hormonal modifications, finally leading to a systemic inflammatory response. Models that allow a systematic investigation of these effects in vivo are scarce. We present a murine model of BD induction, which could aid investigations into the devastating effects of BD on allograft quality. After implementing intra-arterial blood pressure measurement via the common carotid artery and reliable ventilation via a tracheostomy, BD is induced by steadily increasing intracranial pressure using a balloon catheter. Four hours after BD induction, organs may be harvested for analysis or for further transplantation procedures. Our strategy enables the comprehensive analysis of donor BD in a murine model, therefore allowing an in-depth understanding of BD-related effects in solid organ transplantation and potentially paving the way to optimized organ preconditioning.

Accuracy of Non-Invasive Measurement of Mean Arterial Blood Pressure in Patients with Continuous Flow Left Ventricular Assist Devices: A Systematic Review

To determine the accuracy of non-invasive blood mean blood pressure (MAP) assessment in patients with continuous flow left ventricular assist devices. Systematic electronic search was performed on four online databases (PubMed, Scopus, Embase, and Web of Knowledge) for the terms "Blood Pressure" AND ("Heart-Assist Devices" OR "Left ventricular Assist Devices"). Only studies where a non-invasive blood pressure measurement was compared with intra-arterial blood pressure recording were included. A total of 12 studies with 502 participants were included, of those 402 had intra-arterial blood pressure measurement. The median number of participants per study was 30.5 (range: 5-154). The mean age of participants was 53 years old and 77% were male. All were single center prospective studies and intra-arterial blood pressure recordings were performed in the context of routine medical care in the Intensive Care Unit. Characteristics of the included studies are shown in figure 1. Intra-arterial recording was obtained using fluid filled catheter in all studies. Statements regarding the leveling and calibration of transducer 6 (50%) studies. Simultaneous recording occurred in 4 (30%) studies. The correlations between non-invasive and intra-arterial recordings are shown in Figure 2 CONCLUSION: Standardization of quality of signal acquisition and assessment of pulsatility was variable among studies. Non-invasive MAP has variable accuracy and this may adversely influence patients outcomes.

Inflammatory response and optimalisation of perioperative fluid administration during hyperthermic intraoperative intraperitoneal chemotherapy surgery.

Surgical cytoreduction and simultaneous hyperthermic intraoperative intraperitoneal chemotherapy (HIPEC) for peritoneal carcinomatosis has a high incidence of postoperative complications. Inadequate intraoperative volume therapy is a known risk factor for the development of postoperative complications. Another possible risk factor is the inflammatory response due to surgery and HIPEC. The aim of this observational pilot study was to monitor fluid intake in the first 24 hours peri- and postoperative by using a non-invasive cardiac output indicator. Furthermore, we measured circulating cytokines and evaluated the possible relation of these changes of inflammatory response with the non-invasive monitored fluid management. Twenty-four patients undergoing cytoreductive surgery and HIPEC for peritoneal carcinomatosis were included. Patients were randomised into either a liberal fluid management group using intra-arterial blood pressure and central venous pressure measurement or a restrictive group by using intra-arterial blood pressure and central venous pressure measurement with FloTrac/Vigileo monitoring. Cytokines were measured with multiplex immunoassays. We found no difference in the amount of fluid administration in patients undergoing HIPEC surgery with FloTrac/Vigileo monitoring compared to standard care. Furthermore, there was no difference in mortality, ICU and hospital length of stay between both groups. A severe inflammatory response was seen in all patients after the HIPEC procedure with a rapid increase of interleukins and C-reactive protein (CRP). There was however no difference between our intervention and control group in the severity of this reaction. Finally, we found no relation between the severity of the inflammatory response and mortality, or a composite end-point of mortality and severe complications within 30 days postoperative. FloTrac/Vigileo monitoring does not lead to a more restrictive fluid administration and does not influence short-term clinical course in patients undergoing HIPEC surgery. The procedure itself leads to a severe inflammatory response, which is not affected by the use of FloTrac/Vigileo. Our data do not support the use of FloTrac/Vigileo monitoring in patients undergoing HIPEC surgery concerning fluid restrictive management.