Intrathoracic Blood Volume Research Articles

Injection Site Matters: A Comparative Analysis of Transpulmonary Thermodilution via Simultaneous Femoral and Jugular Indicator Injections under Veno-Venous Extracorporeal Membrane Oxygenation Therapy.

Background: The use of veno-venous extracorporeal membrane oxygenation (vv-ECMO) in acute lung failure has witnessed a notable increase. The PiCCO system is frequently used for advanced hemodynamic monitoring in this cohort. Our study aimed to investigate whether the choice of indicator injection site (jugular vs. femoral) in patients undergoing vv-ECMO therapy affects transpulmonary thermodilution (TPTD) measurements using the PiCCO® device (Pulsion Medical Systems SE, Munich, Germany). Methods: In a retrospective single-center analysis, we compared thermodilution-derived hemodynamic parameters after simultaneous jugular and femoral injections in 28 measurements obtained in two patients with respiratory failure who were undergoing vv-ECMO therapy. Results: Elevated values of the extravascular lung water index (EVLWI), intrathoracic blood volume index (ITBVI) and global end-diastolic volume index (GEDVI) were observed following femoral indicator injection compared to jugular indicator injection (EVLWI: 29.3 ± 10.9 mL/kg vs. 18.3 ± 6.71 mL/kg, p = 0.0003; ITBVI: 2163 ± 631 mL/m2 vs. 806 ± 125 mL/m2, p < 0.0001; GEDVI: 1731 ± 505 mL/m2 vs. 687 ± 141 mL/m2, p < 0.0001). The discrepancy between femoral and jugular measurements exhibited a linear correlation with extracorporeal blood flow (ECBF). Conclusions: In a PiCCO®-derived hemodynamic assessment of patients on vv-ECMO, the femoral indicator injection, as opposed to the jugular injection, resulted in an overestimation of all index parameters. This discrepancy can be attributed to mean transit time (MTt) and downslope time-dependent (DSt) variations in GEDVI and cardiac function index and is correlated with ECBF.

Cardiopulmonary interactions in left heart failure.

The primary impact of ventilation and ventilatory efforts on left ventricular (LV) function in left ventricular dysfunction relate to how changes in intrathoracic pressure (ITP) alter the pressure gradients for venous return into the chest and LV ejection out of the chest. Spontaneous inspiratory efforts by decreasing ITP increase both of these pressure gradients increasing venous blood flow and impeding LV ejection resulting in increased intrathoracic blood volume. In severe heart failure states when lung compliance is reduced, or airway resistance is increased these negative swings in ITP can be exacerbated leading to LV failure and acute cardiogenic pulmonary edema. By merely reversing these negative swings in ITP by the use of non-invasive continuous positive airway pressure (CPAP), these profoundly detrimental forces can be immediately reversed, and cardiovascular stability can be restored in moments. This forms the clinical rationale for the immediate use of CPAP for the treatment of acute cardiogenic pulmonary edema. Increasing ITP during positive pressure ventilation decreases the pressure gradients for venous return and LV ejection decreasing intrathoracic blood volume. In a hypovolemic patient even with LV dysfunction this can result in hypotension due to inadequate LV preload. Minor increases in ITP as occur using pressure-limited positive-pressure ventilation primarily reverse the increased LV afterload of negative swings in ITP and if fluid overload was already present, minimally alter cardiac output. The effect of changes in lung volume on LV function are related primarily to its effects on right ventricular (RV) function through changes in pulmonary vascular resistance and overdistention (hyperinflation). In acute lung injury with alveolar collapse, positive pressure ventilation may reduce pulmonary vascular resistance if alveolar recruitment predominates. Hyperinflation, however, impedes diastolic filling while simultaneously increasing pulmonary vascular resistance. Thus, increasing lung volume can reduce RV afterload by reversing hypoxic pulmonary vasoconstriction or increase afterload by overdistention. Hyperinflation can also impede RV filling. All of these processes can be readily identified at the bedside using echocardiography.

Effects of changes in veno-venous extracorporeal membrane oxygenation blood flow on the measurement of intrathoracic blood volume and extravascular lung water index: a prospective interventional study

In severe acute respiratory distress syndrome (ARDS), veno-venous extracorporeal membrane oxygenation (V-V ECMO) has been proposed as a therapeutic strategy to possibly reduce mortality. Transpulmonary thermodilution (TPTD) enables monitoring of the extravascular lung water index (EVLWI) and cardiac preload parameters such as intrathoracic blood volume index (ITBVI) in patients with ARDS, but it is not generally recommended during V-V ECMO. We hypothesized that the amount of extracorporeal blood flow (ECBF) influences the calculation of EVLWI and ITBVI due to recirculation of indicator, which affects the measurement of the mean transit time (MTt), the time between injection and passing of half the indicator, as well as downslope time (DSt), the exponential washout of the indicator. EVLWI and ITBVI were measured in 20 patients with severe ARDS managed with V-V ECMO at ECBF rates from 6 to 4 and 2 l/min with TPTD. MTt and DSt significantly decreased when ECBF was reduced, resulting in a decreased EVLWI (26.1 [22.8–33.8] ml/kg at 6 l/min ECBF vs 22.4 [15.3–31.6] ml/kg at 4 l/min ECBF, p < 0.001; and 13.2 [11.8–18.8] ml/kg at 2 l/min ECBF, p < 0.001) and increased ITBVI (840 [753–1062] ml/m2 at 6 l/min ECBF vs 886 [658–979] ml/m2 at 4 l/min ECBF, p < 0.001; and 955 [817–1140] ml/m2 at 2 l/min ECBF, p < 0.001). In patients with severe ARDS managed with V-V ECMO, increasing ECBF alters the thermodilution curve, resulting in unreliable measurements of EVLWI and ITBVI. German Clinical Trials Register (DRKS00021050). Registered 14/08/2018. https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00021050

The Application of PiCCO-guided Fluid Resuscitation in Patients With Traumatic Shock.

The aim of this study was to evaluate the application of pulse contour cardiac output (PiCCO) in patients with traumatic shock. Seventy-eight patients with traumatic shock were included and grouped. The control group (CG, n = 39) underwent fluid resuscitation through transthoracic echocardiography (TTE) monitoring, and the research group (RG, n = 39) received PiCCO-guided fluid resuscitation. The mechanical ventilation time, duration of vasoactive drug use, and duration of stay in the intensive care unit were lower in the RG compared to the CG (P < .05). At 72h after fluid resuscitation, the mean arterial pressure and central venous pressure in the RG were higher than those in the CG (P < .05). The stroke volume variation and distensibility index of the inferior vena cava were lower at 72h after fluid resuscitation, but the levels of extravascular lung water, global end-diastolic volume index, and intrathoracic blood volume index were higher in the RG (P < .05). The levels of endothelial 1, nitrogen monoxide, tumor necrosis factor-α, procalcitonin, C-reactive protein, and partial pressure of carbon dioxide at 72h after fluid resuscitation in the RG were lower than those in the CG (P < .05). PiCCO-guided liquid resuscitation may help to accurately evaluate the volumetric parameters, alleviate symptoms of ischemia and hypoxia, regulate hemodynamics and blood gas analysis, reduce inflammatory reactions, improve endothelial functions, and effectively guide the usage of vascular active drugs.

Evaluation of volemic status during combined extracorporeal detoxification in patients with severe acute pancreatitis: a retrospective observational study

INTRODUCTION: The morbidity and mortality of severe acute pancreatitis (SAP) remains high. Intensive therapy aimed at stopping hypovolemia, systemic endotoxicosis is a debatable problem. OBJECTIVE: Improving treatment results in patients with SAP by assessing the dynamics of volumetric criteria and the degree of fluid therapy (FT). MATERIALS AND METHODS: The study included 25 patients. First, study group of 9 patient, used standard therapy in conjunction with selective hemoperfusion and continuous veno-venous hemofiltration. Second, control group of 16 patients, who received standard intensive care. FT in the groups was 2.5–3.5 ml/kg/h. Volemic parameters were measured by transpulmonary thermodilution. The central venous pressure and the diameter of the vena cava inferior were assessed. Comparative analysis was performed between two groups. RESULTS: FT in the amount of 58.7 (52.4–59.4) ml/kg/day in group 1, and 58.3 (54.2–61.4) ml/kg/day in group 2 in the first day, up to 83.9 (72.4–86.1) and 79.3 (72.4–84.1) ml/kg/day, was observed by day 3 (p &lt; 0.05), according to the results of transpulmonary thermodilution. From the 1st to the 3rd day, Global end-diastolic volume index increased from 345 (328–412) to 648 (590–690) ml/m2 in group 1, and from 375 (348–413) to 654 (599–701) ml/m2 in group 2 (p &lt; 0.05). Intrathoracic blood volume index increased from 440 (420–510) to 780 (750–40) ml/m2 in group 1 and 430 (417.5–465) to 750 (665–780) ml/m2 in group 2 (p &lt; 0.05). Extravascular lung water index and pulmonary vascular permeability index by 5 days in group 2 increased by 1.8 — 11 (10.5–11.8) and 2.2 times — 6.5 (5.75–7), respectively (p &lt; 0.05). CONCLUSIONS: FT 3.5 ml/kg/h, reaches isovolemia by the 3rd day of therapy. The use of extracorporeal detoxification methods in complex therapy is accompanied by an improvement in clinical and laboratory parameters.

Do alterations in pulmonary vascular tone result in changes in central blood volumes? An experimental study

BackgroundThe effects of selective pulmonary vascular tone alterations on cardiac preload have not been previously examined. Therefore, we evaluated whether changing pulmonary vascular tone either by hypoxia or the inhalation of aerosolized prostacyclin (PGI2) altered intrathoracic or pulmonary blood volume (ITBV, PBV, respectively), both as surrogate for left ventricular preload. Additionally, the mean systemic filling pressure analogue (Pmsa) and pressure for venous return (Pvr) were calculated as surrogate of right ventricular preload.MethodsIn a randomized controlled animal study in 6 spontaneously breathing dogs, pulmonary vascular tone was increased by controlled moderate hypoxia (FiO2 about 0.10) and decreased by aerosolized PGI2. Also, inhalation of PGI2 was instituted to induce pulmonary vasodilation during normoxia and hypoxia. PBV, ITBV and circulating blood volume (Vdcirc) were measured using transpulmonary thermo-dye dilution. Pmsa and Pvr were calculated post hoc. Either the Wilcoxon-signed rank test or Friedman ANOVA test was performed.ResultsDuring hypoxia, mean pulmonary artery pressure (PAP) increased from median [IQR] 12 [8–15] to 19 [17–25] mmHg (p < 0.05). ITBV, PBV and their ratio with Vdcirc remained unaltered, which was also true for Pmsa, Pvr and cardiac output. PGI2 co-inhalation during hypoxia normalized mean PAP to 13 (12–16) mmHg (p < 0.05), but left cardiac preload surrogates unaltered. PGI2 inhalation during normoxia further decreased mean PAP to 10 (9–13) mmHg (p < 0.05) without changing any of the other investigated hemodynamic variables.ConclusionsIn spontaneously breathing dogs, changes in pulmonary vascular tone altered PAP but had no effect on cardiac output, central blood volumes or their relation to circulating blood volume, nor on Pmsa and Pvr. These observations suggest that cardiac preload is preserved despite substantial alterations in right ventricular afterload.

Utilization and Efficacy of Resuscitation Endpoints in Trauma and Burn Patients: A Review Article.

Shock is a sequelae in trauma and burn patients that substantially increases the risk for morbidity and mortality. The use of resuscitation endpoints allows for improved management of these patients, with the potential to prevent further morbidity/mortality. We conducted a review of the current literature on the efficacy of hemodynamic, metabolic, and regional resuscitation endpoints for use in trauma and burn patients. Hemodynamic endpoints included mean arterial pressure (MAP), heart rate (HR), urinary output (UO), compensatory reserve index (CRI), intrathoracic blood volume, and stroke volume variation (SVV). Metabolic endpoints measure cellular responses to decreased oxygen delivery and include serum lactic acid (LA), base deficit (BD), bicarbonate, anion gap, apparent strong ion difference, and serum pH. Mean arterial pressure, HR, UO, and LA are the most established markers of trauma and burn resuscitation. The evidence suggests LA is a superior metabolic endpoint marker. Newer resuscitation endpoint technologies such as point-of-care ultrasound (PoCUS), thromboelastography (TEG), and rotational thromboelastometry (ROTEM) may improve patient outcomes; however, additional research is needed to establish the efficacy in trauma and burn patients. The endpoints discussed have situational strengths and weaknesses and no single universal resuscitation endpoint has yet emerged. This review may increase knowledge and aid in guideline development. We recommend clinicians continue to integrate multiple endpoints with emphasis on MAP, HR, UO, LA, and BD. Future investigation should aim to standardize endpoints for each clinical presentation. The search for universal and novel resuscitation parameters in trauma and burns should also continue.

Preventative Value of Predictive Health Interventions on PICC-Related Thrombosis in Patients with Severe Burns

Background Burn mainly refers to the damage caused by high temperature to the skin and mucous membrane tissue. Seriously, it causes damage to the subcutaneous tissue or subcutaneous mucous membrane, which is easy to induce infection and poses a threat to the life safety of patients.For patients with deep burns, surgical removal of damaged skin and mucosal tissue, Postoperative,immediate coverage of surgical wounds,avoid infection due to body fluid and energy loss with related tissue necrosis.The clinical treatment period for critical burn patients is longer and high incidence of postoperative complications.The corresponding nursing intervention while undergoing treatment can help to eliminate the impact of the bad psychological state on the patients, improve the treatment compliance, and reduce the occurrence of complications. Objective Evaluation of the value of predictive health intervention in preventing thrombosis associated with Peripherally Inserted Central Catheter (PICC) via peripheral vein in critically ill burn patients Methods Select 90 patients with severe burn treated by PICC infusion from January 2019- February 2021, Group by reference to intervention methods, with 45 using conventional health intervention (control group) and another 45 using predictive health interventions (observation group). The incidence of pulmonary and wound infection, the incidence of adverse events associated with PICC catheterization and wound healing time were recorded in the two groups. The degree of pain was evaluated by visual simulation (VAS) score, and the differences of platelet, D- dimer (D-D) and hemodynamics were detected in the two groups Results The incidence of pulmonary infection, PICC associated thrombus and total adverse events in the observation group was lower, and higher rate of functional recovery,but less wound healing time with control group,which had statistical significance (P&lt;0.05) .Incidence of wound infection, incidence of catheter blockage, incidence of unplanned extubation,the difference was not statistically significant (P&gt;0.05) .Comparison before intervention/The pain score decreased at 7 ck 14d&gt; 21d (P&lt;0.05), and the observation group was lower than the control group (P&lt;0.05) .Intervention of the 7d, 14d two sets all platelet elevation (P&lt; 0.05) ,but D-D concentration decreases (P&lt; 0.05) .Intervention of the 7d&gt; 14d two sets was increased of the intrathoracic blood volume index (ITBVI) (P&lt;0.05) , but extravascular lung water index (EVLWI) and mean arterial pressure (MAP) the difference was not statistically significant (P&gt;0.05). Conclusions Predictive health intervention can reduce the pain degree of critically burned patients, reduce the incidence of adverse events such as infection and PICC-related thrombosis, and promote wound recovery.

Predictive value of carotid ultrasound in combination with passive leg raising on fluid responsiveness in critically ill patients

To investigate the value of monitor carotid velocity time integral (VTI) and corrected flow time (FTc) by bedside ultrasound before and after passive leg raising (PLR) in predicting fluid responsiveness in critically ill patients. A prospective observational study was conducted. Fifty patients with critical illness admitted to the First People's Hospital of Fuyang Hangzhou from January 2020 to March 2021 were enrolled. The clinical data including the gender, age, body mass index (BMI), acute physiology and chronic health evaluation II (APACHE II) score, and the duration of mechanical ventilation were recorded. The changes of carotid VTI and FTc were measured by bedside ultrasound, and the values of heart rate, mean arterial pressure (MAP), central venous pressure (CVP), stroke volume index (SVI), and intrathoracic blood volume index (ITBVI) were measured by pulse indicated continuous cardiac output (PiCCO) monitor before and after PLR in all patients. According to the changes of SVI before and after PLR, the patients were divided into fluid responsiveness positive group with the change rate of SVI ≥ 15% and fluid responsiveness negative group with the change rate of SVI < 15%. The differences in the values of VTI, FTc, CVP, and ITBVI obtained before and after PLR (ΔVTI, ΔFTc, ΔCVP and ΔITBVI) were calculated and then compared between the two groups. The predictive values of these indicators on fluid responsiveness in critically ill patients were analyzed by receiver operator characteristic curve (ROC curve), and their relationship with the difference in SVI (ΔSVI) obtained before and after PLR was evaluated by Pearson correlation analysis. Fifty patients were all enrolled in this study, in which 27 patients were fluid response and 23 patients were fluid nonresponse. Basic clinical data were not different between the two groups. The values of ΔVTI, ΔFTc, ΔCVP, and ΔITBVI in fluid response were all significantly higher than those in fluid nonresponse [ΔVTI (cm): 2.07±1.16 vs. 0.67±0.86, ΔFTc (ms): 4.00±6.10 vs. 0.01±2.26, ΔCVP (cmH2O, 1 cmH2O = 0.098 kPa): 1.67±1.14 vs. 1.00±1.17, ΔITBVI (mL/m2): 98±69 vs. 48±70, all P < 0.05]. ROC curve analysis showed that ΔVTI, ΔFTc, ΔCVP and ΔITBVI were all positive for predicting fluid responsiveness, their area under ROC curve (AUC) and 95% confidence interval (95%CI) were 0.870 (0.769-0.972), 0.694 (0.547-0.841), 0.684 (0.535-0.832) and 0.709 (0.564-0.855), respectively. When using ΔVTI 0.92 cm, ΔFTc 1.45 ms, ΔCVP 1.50 cmH2O and ΔITBVI 44.50 mL/m2 as the threshold values, the sensitivities were 96.3%, 63.0%, 44.4% and 81.5%, and the specificities were 65.2%, 78.3%, 82.6% and 56.5%, respectively, in which the predictive value of ΔVTI was the largest. Pearson correlation analysis indicated that ΔVTI, ΔFTc, ΔCVP, and ΔITBVI were positively associated with ΔSVI (r values were 0.971, 0.334, 0.440, 0.650, P values were 0.000, 0.018, 0.001, 0.000, respectively). Carotid ΔVTI and ΔFTc monitored by bedside ultrasound before and after PLR could be as effective as conventional indicators in predicting fluid responsiveness in critically ill patients, and the predictive value of ΔVTI was better than others.

МОНИТОРИНГ ЦЕНТРАЛЬНОЙ ГЕМОДИНАМИКИ У ПАЦИЕНТОВ С СИНДРОМОМ ПОЛИОРГАННОЙ НЕДОСТАТОЧНОСТИ

Objective: comparative analysis of the use of PiCCO monitoring for correction of the intensive care in patients with multiple organ dysfunction syndrome (MODS) after abdominal and cardiac surgery. Material and methods. A prospective cohort study was carried out in 19 patients with MODS after abdominal (n=10) and cardiac (n=9) interventions. Of these, 13 men and 6 women, aged 63 (58-69) years, their height was 176 (174-180) cm, body weight - 90 (80-100) kg. Central hemodynamic parameters were monitored in these patients by the PiCCO method. Several steps have been distinguished in the study: 1st stage - 1st day after surgery, 2nd stage - 2nd day after surgery, etc. Results. In patients after cardiac surgery, compared with the group of patients after abdominal surgery, significantly (p &lt;0.001) lower preload indices (global end-diastolic volume and index, intrathoracic blood volume and index) were noted at 1-2 stages, as well as significantly (p&lt;0.05) lower rates of contractility (continuous cardiac output and index at 1-4 stages, stroke volume and index at 1-5 stages). When analyzing the treatment in patients after cardiac surgery, the frequency of dobutamine use (p=0.017) and the frequency of simultaneous use of 3 vasoactive substances (p=0.0495) were statistically significantly higher than in patients undergoing abdominal surgery. Conclusions. Monitoring of central hemodynamics enables to individualize infusion therapy, vasopressor and inotropic support in patients with MODS after abdominal and cardiac surgery.

Extravascular Lung Water and Intrathoracic Blood Volume Index Are Associated With Liver Function in Brain Dead Donors for Organ Transplant.

Hemodynamic measurements during organ transplant procedures are essential. In this observational study, we measured clinical and hemodynamic parameters in 11 patients with advanced pulse indicator continuous cardiac output monitoring. Normally distributed clinical data were calculated as means ± standard deviation; hemodynamic, metabolic, and respiratory parameters related to liver and renal function were compared by linear regression analysis using Pearson correlation. Compared with the normal range, systemic vascular resistance was high (2278.02 ± 719.6 dyne·s/cm²/m²) and intrathoracic blood volume was low (787.37 ± 224.01 mL/m²) in our patient group. C-reactive protein and interleukin 6 levels were 96.26 ± 68.10 mg/mL and 246.24 ± 355.74 mmol/L, respectively. Liver and renal function parameters were in normal ranges. Extravascular lung water was correlated with total, conjugated, and unconjugated bilirubin and albumin (r = 0.342/P = .005; r = 0.338/ P = .005; r = 0.394/P = .001, and r = 0.358/P = .003) but not with aspartate aminotransferase, alanine aminotransferase, blood urea nitrogen, and serum creatinine. Intrathoracic blood volume index was correlated with total bilirubin, unconjugated bilirubin, and albumin (r = 0.324/P = .007; r = 0.394/P = .001, and r = 0.296/P = .015) but not with conjugated bilirubin, aspartate aminotransferase, alanine aminotransferase, blood urea nitrogen, and serum creatinine. Lactate was not correlated with total bilirubin, unconjugated bilirubin, albumin, and serum creatinine, but base excess was correlated with total bilirubin, unconjugated bilirubin, alanine aminotransferase, and albumin. PO₂ and Pco₂ were not correlated with liver function, although PO₂ was correlated with albumin. No correlations were shown between intrathoracic blood volume index, extravascular lung water, and liver function, but metabolic parameters, including base excess and lactate, were correlated with liver function. Pulse indicator continuous cardiac output monitoring may be a useful method to assess organ function and tissue perfusion in organ transplant.

Application of pulse contour cardiac output monitoring technology in fluid resuscitation of severe burn patients in shock period

Objective: To investigate the application of pulse contour cardiac output (PiCCO) monitoring technology in fluid resuscitation of severe burn patients in shock period. Methods: From January 2015 to December 2019, 33 patients with severe burns who were hospitalized in Guangzhou Red Cross Hospital, meeting the inclusion criteria, were recruited into a retrospective cohort study with their clinical information collected. The patients were divided into PiCCO monitoring group with 15 cases (13 males and 2 females, aged (43±13) years) and routine monitoring group with 18 cases (14 males and 4 females, aged (39±9) years) according to the monitoring method used. After admission, all the patients were rehydrated following the rehydration formula of the Third Military Medical University for shock period. In routine monitoring group, the fluid resuscitation of patients was performed by monitoring indicators such as urine volume and blood pressure, while PiCCO monitoring was performed among patients in PiCCO monitoring group, and their fluid resuscitation was guided by the patient's condition and the hemodynamic parameters (without pursuing normal levels of the parameters) of PiCCO monitoring on the basis of normal monitoring indicators in routine monitoring group. The colloids coefficients, the electrolyte coefficients (compared with the corresponding rehydration formula value of 0.75 mL·kg(-1)·% total body surface area (TBSA)(-1) of the Third Military Medical University for shock period during the first 24 h post injury), the total rehydration coefficients, and the urine volumes during the first and second 24 h post injury, the lactic acid level, the base excess level, and the oxygenation index at admission and 24, 48 h after admission, and the mechanical ventilation time, the wound healing time, and the death ratio of patients in the two groups were recorded. The cardiac index, the global end-diastolic volume index (GEDVI), the intrathoracic blood volume index (ITBVI), the extravascular lung water index (EVLWI), and the systemic vascular resistance index (SVRI) of patients in PiCCO monitoring group at post injury hour 24, 48, and 72 and the abnormal cases were recorded. Data were statistically analyzed with Fisher's exact probability test, independent-sample or one-sample t test, analysis of variance for repeated measurement, and Bonferroni correction. Results: During the first 24 h post injury, the colloids coefficients of patients in PiCCO monitoring group was (0.69±0.15) mL·kg(-1)·%TBSA(-1), which was significantly less than (0.85±0.16) mL·kg(-1)·%TBSA(-1) in routine monitoring group (t=-2.612, P<0.05). Compared with the rehydration formula value of the Third Military Medical University for shock period, only the colloids coefficient of patients in routine monitoring group during the first 24 h post injury was significantly increased (t=2.847, P<0.05). There were no statistically significant differences between the two groups in the colloids coefficients of patients during the second 24 h post injury, or the electrolyte coefficients, the total rehydration coefficients, the urine volumes of patients during the first and the second 24 h post injury (t=0.579, -0.011, 0.417, -1.321, -0.137, 0.031, 1.348, P>0.05). The lactic acid level, the base excess level, the oxygenation index of patients at admission and 48 h after admission, and the oxygenation index of patients at 24 h after admission between the two groups were similar (t=-1.837, 0.620, 0.292, -1.792, 1.912, -0.167, 1.695, P>0.05). The levels of lactic acid and base excess of patients in PiCCO monitoring group were (4.8±1.4) and (1.2±5.5)mmol/L, respectively, which were significantly better than (7.0±1.5) and (-2.8±3.0) mmol/L in routine monitoring group at 24 h after admission (t=-3.904, 2.562, P<0.05 or P<0.01). There were no statistically significant differences between the two groups in the mechanical ventilation time or the wound healing time of patients (t=-0.699, -0.697, P>0.05), or the death ratio of patients (P>0.05). In PiCCO monitoring group, the GEDVI, and the ITBVI of patients were lower than the normal low values at post injury hour 24 and 48, which were in the normal range at post injury hour 72; the cardiac index of patients increased gradually and recovered to normal at post injury hour 48; the SVRI of patients increased significantly at post injury hour 24 and then gradually decreased to normal; the EVLWI average of patients at all time points post injury were less than 10 mL/kg. At post injury hour 24, most of the hemodynamic parameters of more than or equal to 8/15 patients in PiCCO monitoring group were abnormal, and the abnormal proportion decreased later. Conclusions: On the basis of traditional monitoring indicators, the use of PiCCO monitoring technology combined with the patient's condition (without pursuing normal levels of the parameters) in guiding the fluid resuscitation in severe burn patients can reduce the usage of colloid and better improve tissue perfusion, with the resuscitation effect being better than conventional monitoring.

Evaluation of the association between extravascular lung water and prognosis of sepsis: A protocol of systematic review.

Background:The purpose of this study is to explore the association between extravascular lung water (EVLW) and prognosis of sepsis (PS).Methods:We will carry out comprehensive literature search in electronic databases (PUBMED/MEDLINE, EMBASE, CENTRAL, WorldSciNet, PsycINFO, Allied and Complementary Medicine Database, CBM, and CNKI) and additional sources. All electronic databases will be searched from their initial to the present without language restrictions. Case-controlled studies reporting the association between EVLW and PS will be evaluated for inclusion. Outcomes of interest will include mortality rate, extravascular lung water index, pulmonary vascular permeability index, blood lactate clearance, oxygenation index, blood gas analysis, PaO2/FiO2, cardiac output index, global end diastolic volume index, intrathoracic blood volume index, systemic resistance index, acute physiology and chronic health scoring system II, and infection-related organ failure scoring system. Study quality will be evaluated using Newcastle-Ottawa Tool, and statistical analysis will be performed utilizing RevMan 5.4 software.Results:This study will summarize the most recent evidence to investigate the association between EVLW and PS.Conclusions:The results of this study will provide an exhaustive view of the association between EVLW and PS.Study registration OSF:osf.io/vhnxw.

Effect of different fluid resuscitation strategies on renal function in patients with septic shock induced acute kidney injury

To compare the therapeutic effect of fluid resuscitation strategy guided by pulse-indicated continuous cardiac output (PiCCO) monitoring and early goal-directed therapy (EGDT) on renal function of acute kidney injury (AKI) patients caused by septic shock. Septic shock patients with AKI admitted to the intensive care unit (ICU) of Tianjin Fifth Central Hospital and Teda International Cardiovascular Hospital from March 2017 to February 2020 were enrolled. All patients were given fluid resuscitation. Patients were divided into PiCCO-guided fluid resuscitation group [PiCCO group, intrathoracic blood volume index (ITBVI) was maintained between 850-1 000 mL/m2] and EGDT-guided fluid resuscitation group [EGDT group, central venous pressure (CVP) was maintained between 8-12 mmHg (1 mmHg = 0.133 kPa) or CVP ≤ 15 mmHg when patients received mechanical ventilation (MV)] according to both the patient's condition and the informed consent of the patient's family. The changes of heart rate (HR), mean arterial pressure (MAP), CVP, blood lactic acid (Lac), fluid balance, urine volume and serum creatinine (SCr) at 6, 24, and 48 hours after fluid resuscitation in the two groups were observed, and the renal replacement therapy (RRT), duration of MV, length of ICU stay and 28-day mortality between the two group were compared. (1) A total of 94 patients were enrolled, including 51 in the EGDT group and 43 in the PiCCO group. There was no significant difference in gender, age, acute physiology and chronic health evaluation II (APACHE II) score, sequential organ failure assessment (SOFA) score, procalcitonin (PCT), HR, MAP, CVP, Lac or SCr at ICU admission between the two groups. (2) The parameters of hemodynamics, fluid balance, urine volume and SCr were improved with the time of resuscitation in the two groups, and there was no significant difference in HR, MAP or Lac between the two groups. Compared with the EGDT group, the CVP decreased significantly at 24 hours and 48 hours after fluid resuscitation in the PiCCO group (mmHg: 9.1±0.9 vs. 12.0±1.3 at 24 hours, 8.0±1.0 vs. 10.2±1.3 at 48 hours), the fluid balance significantly decreased (mL: 2 929.8±936.3 vs. 3 898.4±923.5 at 24 hours, 3 143.5±1 325.4 vs. 4 843.8±1 326.7 at 48 hours), and the condition of urine volume and SCr were better in the PiCCO group [urine volume (mL×kg-1×h-1): 1.02±0.21 vs. 0.79±0.14 at 24 hours, 1.28±0.18 vs. 0.94±0.22 at 48 hours; SCr (μmol/L): 145.7±37.6 vs. 164.3±46.4 at 24 hours, 128.4±33.6 vs. 143.5±37.7 at 48 hours), with significant differences (all P < 0.05). (3) Compared with the EGDT group, the rate of RRT in the PiCCO group was lower [11.6% (5/43) vs. 17.6% (9/51)], the duration of MV and the length of ICU stay were shorter [duration of MV (days): 4.64±1.31 vs. 6.50±2.19, length of ICU stay (days): 10.35±3.50 vs. 14.50±5.78), with significant differences (all P < 0.05). There was no significant difference in the 28-day mortality between the PiCCO group and EGDT group [14.0% (6/43) vs. 15.7% (8/51), P > 0.05]. Fluid resuscitation strategy guided by PiCCO in septic shock patients with AKI can reduce the amount of fluid load, improve renal function, shorten the MV duration and length of ICU stay, and shows clinical significance.

Lactate and lactate clearance in critically burned patients: usefulness and limitations as a resuscitation guide and as a prognostic factor

ObjectiveLactate levels to guide resuscitation in critically burned patients are controversial. The purpose of our study was to determine whether absolute lactate values or lower lactate clearance predict mortality, and whether these are useful tools in the resuscitation phase. MethodsWe conducted a prospective, unicentric, observational study of a cohort of 214 burn patients admitted in the Burn Intensive Care Unit. We collected demographic and laboratory data, complications, absolute lactate levels and lactate clearance every 8 h since admission to 72 h. In critical patients we monitored hemodynamic parameters with transpulmonary thermodilution. We used Student’s t-test or nonparametric tests, mixed models and Pearson and Spearman methods, Fisher’s exact and chi-squared test. ResultsOf the 214 patients, 76.6% were male, mean age were 46 ± 15 years and 23.0 ± 19.5% of Total Basal Surface Area (TBSA) burned. Initial mean absolute levels of lactate were 2.02 ± 1.62 mmol/L in survivors vs. 4.05 ± 3.90 mmol/L in nonsurvivors. Initial elevated lactate levels increased mortality (p < .001), length of ICU stay, mechanical ventilation and shock. In the subgroup of burned TBSA < 20%, lowering the lactate cut-off point from 2.0 to 1.8 mmol/L improved the mortality prediction (OR:9.3). We found no relationship between lactate clearance in the first 24 h and mortality. In more severe patients (> 20% TBSA burned and initial lactate levels > 2), a good correlation was found between lactate and cardiac index; but not with intrathoracic blood volume index (ITBVI). Patients with low ITBVI preload (< 600 mL/m2) did not show significant differences in lactate clearance compared with those with ITBVI > 600. ConclusionsInitial elevated lactate levels are a factor of poor prognosis and the cut-off point that best predicts mortality should be adjusted in the patients with TBSA burned < 20%.The global clearance of lactate in the first 24 h, unlike what occurs in other injuries, does not correlate with mortality.Monitoring lactate can ensure adequate peripheral perfusion during resuscitation with lower than normal fluid preload values.

VOLEMIC AND HEMODYNAMIC STATUS OF PATIENTS WITH COMORBIDITY OF CORONARY HEART DISEASE AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE BEFORE AND AFTER MYOCARDIAL REVASCULARIZATION

Introduction . The comorbidity of chronic obstructive pulmonary disease (COPD) and coronary heart disease (CHD) significantly worsens the clinical course of these pathologies, which determines the need for careful hemodynamic monitoring during coronary artery bypass grafting (CABG). Aim. To evaluate the parameters of central and pulmonary hemodynamics during the performance of CABG under conditions of cardiopulmonary bypass (CPB) in patients with comorbidity of IHD and COPD. Materials and methods. Two groups of patients with IHD before and after CABG were examined. The first group included 11 patients with coronary heart disease in combination with COPD II-III severity without exacerbation, the second group included 29 patients with coronary heart disease without pulmonary pathology. Volumetric and hemodynamic parameters were measured by transpulmonary thermodilution using a Drager Delta XL monitor and the Pulsion PiCCO Plus module (Germany) at three stages of the study: after the start of artificial lung ventilation; completion of the CPB procedure; 24 hours after IR. Results. For patients with comorbidity of coronary heart disease and COPD, a specific set of volumic and hemodynamic parameters was characteristic that distinguishes them from persons with coronary artery disease without pulmonary pathology. In the early postoperative period, this was manifested by the formation of a hypokinetic type of blood circulation, an increase in systemic vascular resistance, a less noticeable decrease in the global final diastolic volume, intrathoracic and pulmonary blood volumes. In addition, in patients with cardio-respiratory comorbidity, the maximum values of the indices of extravascular water in the lungs and permeability of the pulmonary vessels were recorded. Timely diagnosis of these disorders contributed to the restoration of pulmonary hemodynamics and water balance. Conclusion. When conducting CABG in patients with comorbidity of IHD and COPD, it is advisable to use the method of transpulmonary thermodilution, which provides more accurate control of hemodynamics and a personalized approach to correcting its disorders.

Application of pulse index continuous cardiac output system in elderly patients with acute myocardial infarction complicated by cardiogenic shock: A prospective randomized study.

BACKGROUNDCardiogenic shock (CS) secondary to acute myocardial infarction (AMI) complicates management of the condition, and often leads to poor prognosis. Prompt and accurate monitoring of cardiovascular and accompanying hemodynamic changes is crucial in achieving adequate management of the condition. Advances in technology has availed procedures such as pulse index continuous cardiac output (PiCCO), which can offer precise monitoring of cardiovascular functions and hemodynamic parameters. In this study, PiCCO is evaluated for its potential utility in improving management and clinical outcomes among elderly patients with AMI complicated by CS.AIMTo assess whether use of the PiCCO system can improve clinical outcomes in elderly patients with AMI complicated by CS.METHODSPatients from emergency intensive care units (EICU) or coronary care units (CCU) were randomized to receive PiCCO monitoring or not. The APACHE II score, SOFA score, hs-TnI, NT-proBNP, PaO2/FiO2 ratio and lactate levels on day 1, 3 and 7 after treatment were compared. The infusion and urine volume at 0-24 h, 24-48 h and 48-72 h were recorded, as were the cardiac index (CI), extravascular lung water index (EVLWI), intrathoracic blood volume index (ITBVI) and global end diastolic volume index (GEDVI) at similar time intervals.RESULTSSixty patients with AMI complicated by CS were included in the study. The PiCCO group had a significantly lower APACHE II score, SOFA score, hs-TnI and NT-proBNP levels on day 1, 3 and 7 after treatment. The infusion and urine volume during 0-24 h in the PiCCO group were significantly greater, and this group also showed significantly higher ADL scores. Furthermore, the PiCCO group spent lesser days on vasoactive agents, mechanical ventilation, and had a reduced length of stay in EICU/CCU. Additionally, the CI was significantly higher at 48 h and 72 h in the PiCCO group compared with that at 24 h, and the EVLWI, ITBVI and GEDVI were significantly decreased at 48 h and 72 h.CONCLUSIONApplying the PiCCO system could improve the clinical outcomes of elderly patients with AMI complicated by CS.

Effect of goal-directed therapy bundle based on PiCCO parameters to the prevention and treatment of acute kidney injury in patients after cardiopulmonary bypass cardiac operation: a prospective observational study

To explore the effect of goal-directed therapy bundle based on pulse-indicated continuous cardiac output (PiCCO) parameters to the prevention and treatment of acute kidney injury (AKI) in patients after cardiopulmonary bypass cardiac operation. A prospective observational study was conducted. The adult patients with selective cardiopulmonary bypass cardiac operation admitted to the Third People's Hospital of Chengdu from December 2015 to January 2018 were enrolled. All patients were divided into two groups based on informed consent for PiCCO monitor at the time of admission to the intensive care unit (ICU): regular monitoring and treatment group (group A) and goal-directed therapy group based on PiCCO parameters (group B). In group A, the restrictive capacity management strategy was implemented to maintain the mean arterial pressure (MAP) > 65 mmHg (1 mmHg = 0.133 kPa) and the central venous pressure (CVP) between 8 mmHg and 10 mmHg. In group B, volume and hemodynamic status were optimized depending on PiCCO parameters to a goal of cardiac index (CI) > 41.68 mL×s-1×m-2, global end diastolic volume index (GEDVI) > 700 mL/m2 or intrathoracic blood volume index (ITBVI) > 850 mL/m2, extravascular lung water index (EVLWI) < 10 mL/kg, and MAP > 65 mmHg. Then the changes in hemodynamics and different prognosis of the patients in two groups were observed. Risk factors affecting the AKI were analyzed by Logistic regression. 171 cases were included, with 68 in group A and 103 in group B. There were no significant differences in gender, age, pre-operative scores by European system for cardiac operative risk evaluation (EuroScore), operation ways, operation time, cardiopulmonary bypass time, intraoperative dominant liquid equilibrium quantity, the use of intra-aortic balloon counterpulsation (IABP) during operation, and serum creatinine (SCr) level at the time of admission to ICU between the two groups. There were no significant differences in CVP within 24 hours after admission to ICU between the two groups. MAP in group B was significantly higher than that in group A at 8 hours and 16 hours after ICU admission (mmHg: 68.9±6.3 vs. 66.7±5.1, 69.0±4.9 vs. 67.0±5.3, both P < 0.05). Sequential organ failure assessment (SOFA) score in group B was significantly lower than that in group A at 24 hours after ICU admission (5.7±2.2 vs. 6.9±2.8, P < 0.05). Dominant liquid equilibrium quantity in group B was significant higher than that in group A at 24 hours after ICU admission (mL/kg: 7.1±6.2 vs. -0.1±8.2, P < 0.01), but there was no significant difference of that between groups at 48 hours and 72 hours after ICU admission. Compared with group A, incidence of combination with AKI during 72 hours after ICU admission was significantly decreased in group B [48.5% vs. 69.1%; odds ratio (OR) = 0.422, 95% confidence interval (95%CI) = 0.222-0.802, P < 0.05], and incidence of moderate to severe AKI was also significantly decreased in group B (19.4% vs. 35.3%; OR = 0.442, 95%CI = 0.220-0.887, P < 0.05). There was no significant difference in usage of continuous renal replacement therapy (CRRT) after ICU admission between both groups (group A was 4.4%, group B was 4.9%, P > 0.05). It was shown by correlation analysis that only MAP and CI at 8 hours after ICU admission were significantly negatively correlated with AKI (MAP and AKI: r = -0.697, P = 0.000; CI and AKI: r = -0.664, P = 0.000). It was shown by Logistic regressive analysis that the MAP and CI at 8 hours after ICU admission were independent risk factors that influence the incidence of AKI at 72 hours after ICU admission (MAP: OR = 0.736, 95%CI = 0.636-0.851, P = 0.000; CI: OR = 0.006, 95%CI = 0.001-0.063, P = 0.000). There were no significant differences in the duration of mechanical ventilation, the length of ICU stay, the post-operation complications (except AKI), 7-day and 28-day mortality between the two groups. Goal-directed therapy bundle based on PiCCO parameters reduced the incidence of AKI in patients after cardiopulmonary bypass cardiac operation and improved the severity of systemic disease. However, it did not reduce the duration of mechanical ventilation, length of ICU stay, the incidence of complications (except AKI), short-term mortality. The MAP and CI at 8 hours after ICU admission were independent risk factors that influence the incidence of AKI in patients after cardiopulmonary bypass cardiac operation.

Intravenous administration of normal saline may be misinterpreted as a change of end-expiratory lung volume when using electrical impedance tomography

Electrical impedance tomography (EIT) is a noninvasive imaging modality that allows real-time monitoring of regional lung ventilation. The aim of the study is to investigate whether fast saline infusion causes changes in lung impedance that could affect the interpretation of EIT data. Eleven pigs were anaesthetized and mechanically ventilated. A bolus of 500 mL of normal saline was administered rapidly. Two PEEP steps were performed to allow quantification of the effect of normal saline on lung impedance. The mean change of end-expiratory lung impedance (EELI) caused by the saline bolus was equivalent to a virtual decrease of end-expiratory lung volume (EELV) by 227 (188–250) mL and decremental PEEP step of 4.40 (3.95–4.59) cmH2O (median and interquartile range). In contrast to the changes of PEEP, the administration of normal saline did not cause any significant differences in measured EELV, regional distribution of lung ventilation determined by EIT or in extravascular lung water and intrathoracic blood volume. In conclusion, EELI can be affected by the changes of EELV as well as by the administration of normal saline. These two phenomena can be distinguished by analysis of regional distribution of lung ventilation.

Pulse Pressure Variations and Plethysmographic Variability Index Measured at Ear Are Able to Predict Fluid Responsiveness in the Sitting Position for Neurosurgery

Pulse pressure variation (PPV) and plethysmographic variability index (PVI), dynamic indicators of preload dependence based on heart-lung interactions, are used to predict fluid responsiveness in mechanically ventilated patients in the supine position. The sitting position for neurosurgery, by changing intrathoracic blood volume, could affect the capacity of PPV and PVI to predict fluid responsiveness. The aim of the study was to assess the ability of PPV and PVI to predict fluid responsiveness during general anesthesia in the sitting position. In total, 31 patients were included after settling in the sitting position but before surgery began. PPV, PVI with a finger sensor (PVI finger), and PVI with an ear sensor (PVI ear) were recorded before and after a fluid challenge of hydroxylethylstarch 250 mL over 10 minute. Esophageal Doppler was used to record stroke volume. Patients were defined as fluid responders if stroke volume increased by more than 10% after the fluid challenge. In total, 13 (42%) patients were fluid responders. PPV and PVI ear were higher in responders than in nonresponders before the fluid challenge (12±5 vs. 7±3; P=0.0005 and 14±5 vs. 8±3; P=0.001, respectively). Areas under the receiver-operating curves to predict fluid responsiveness were 0.87 for PPV (P<0.0001), 0.87 for PVI ear (P<0.0001), and 0.64 for PVI finger (P=0.17). PPV ≥8% or PVI ear ≥11% predicted fluid responsiveness with sensitivities of 83% for both, and specificities of 83% and 91%, respectively. However PVI ear data were not available in 26% of patients. PPV can be used to predict fluid responsiveness in the sitting position for neurosurgery.