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Purpose: The preferred vasopressor in post-cardiac arrest shock has not been established with robust clinical outcomes data. Our goal was to perform a systematic review and meta-analysis comparing rates of in-hospital mortality, refractory shock, and hemodynamic parameters in post-cardiac arrest patients who received either norepinephrine or epinephrine as primary vasopressor support., Methods: We conducted a search of PubMed, Cochrane Library, and CINAHL from 2000 to 2022. Included studies were prospective, retrospective, or published abstracts comparing norepinephrine and epinephrine in adults with post-cardiac arrest shock or with cardiogenic shock and extractable post-cardiac arrest data. The primary outcome of interest was in-hospital mortality. Other outcomes included incidence of arrhythmias or refractory shock., Results: The database search returned 2646 studies. Two studies involving 853 participants were included in the systematic review. The proposed meta-analysis was deferred due to low yield. Crude incidence of in-hospital mortality was numerically higher in the epinephrine group compared with norepinephrine in both studies, but only statistically significant in one. Risk of bias was moderate to severe for in-hospital mortality. Additional outcomes were reported differently between studies, minimizing direct comparison., Conclusion: The vasopressor with the best mortality and hemodynamic outcomes in post-cardiac arrest shock remains unclear. Randomized studies are crucial to remedy this., Competing Interests: Declaration of Competing Interest The following authors report no conflict of interest: CL, CC, NA, LR. The following authors received funding by Spero Therapeutics-provided unrestricted research grant via its Investigator Initiated Research Program: BF, MR, GS. GS reports participating in an advisory board meeting for Hema Biologics in 2022 regarding blood factor products. CB reports grant funding from Alexion/Astra Zeneca Rare Disease., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: Compensatory reserve measurement (CRM) is a novel noninvasive monitoring technology designed to assess physiologic reserve using feature interrogation of arterial pulse waveforms. This study was conducted to validate clinically relevant CRM values with a simplified color-coded dashboard view., Methods: We performed a prospective observational study of 300 injured patients admitted to a level I trauma center. Compensatory reserve measurement was recorded upon emergency department admission. Data collected to complement the analysis included patient demographics, vital signs, lifesaving interventions, Injury Severity Score (ISS), and outcomes. Threshold values of CRM were analyzed for predictive capability of hemorrhage., Results: A total of 285 patients met the inclusion criteria. Mean age of the population was 47 years, and 67% were male. Hemorrhage was present in 32 (11%), and lifesaving intervention was performed in 40 (14%) patients. Transfusion of packed red blood cells was administered in 33 (11.6%) patients, and 21 (7.4%) were taken to the operating room for surgical or endovascular control of hemorrhage. Statistical analyses were performed to identify optimal threshold values for three zones of CRM to predict hemorrhage. Optimal levels for red, yellow, and green areas of the dashboard view were stratified as follows: red if CRM was less than 30%, yellow if CRM was 30% to 59%, and green if CRM was 60% or greater. Odds of hemorrhage increased by 12-fold (odds ratio, 12.2; 95% confidence interval, 3.8-38.9) with CRM less than 30% (red) and 6.5-fold (odds ratio, 6.5; 95% confidence interval, 2.7-15.9) with CRM of equal to 30% to 59% (yellow) when compared with patients with CRM of 60% or greater. The area under the receiver operating characteristic curve for three-zone CRM was similar to that of continuous CRM (0.77 vs. 0.79) but further increased the ability to predict hemorrhage after adjusting for ISS (area under the receiver operating characteristic curve, 0.87)., Conclusion: A three-zone CRM could be a potentially useful predictor of hemorrhage in trauma patients with added capabilities of continuous monitoring and a real-time ISS assessment. These data substantiate easily interpretable threshold dashboard values for triage with potential to improve injury outcomes., Level of Evidence: Diagnostic, level II.

Background: Hemorrhage remains the leading cause of death following traumatic injury in both civilian and military settings. Heart rate variability (HRV) and heart rate complexity (HRC) have been proposed as potential "new vital signs" for monitoring trauma patients; however, the added benefit of HRV or HRC for decision support remains unclear. Another new paradigm, the compensatory reserve measurement (CRM), represents the integration of all cardiopulmonary mechanisms responsible for compensation during relative blood loss and was developed to identify current physiologic status by estimating the progression toward hemodynamic decompensation. In the present study, we hypothesized that CRM would provide greater sensitivity and specificity to detect progressive reductions in central circulating blood volume and onset of decompensation as compared with measurements of HRV and HRC., Methods: Continuous, noninvasive measurements of compensatory reserve and electrocardiogram signals were made on 101 healthy volunteers during lower-body negative pressure (LBNP) to the point of decompensation. Measures of HRV and HRC were taken from electrocardiogram signal data., Results: Compensatory reserve measurement demonstrated a superior sensitivity and specificity (receiver operator characteristic area under the curve [ROC AUC] = 0.93) compared with all HRV measures (ROC AUC ≤ 0.84) and all HRC measures (ROC AUC ≤ 0.86). Sensitivity and specificity values at the ROC optimal thresholds were greater for CRM (sensitivity = 0.84; specificity = 0.84) than HRV (sensitivity, ≤0.78; specificity, ≤0.77), and HRC (sensitivity, ≤0.79; specificity, ≤0.77). With standardized values across all levels of LBNP, CRM had a steeper decline, less variability, and explained a greater proportion of the variation in the data than both HRV and HRC during progressive hypovolemia., Conclusion: These findings add to the growing body of literature describing the advantages of CRM for detecting reductions in central blood volume. Most importantly, these results provide further support for the potential use of CRM in the triage and monitoring of patients at highest risk for the onset of shock following blood loss.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the authors due to errors in the data. The authors indicated that they expanded the original sample size from 12 to 50, to study blood circulation upon other types of burns. At the same time, they further verified the results reported in this paper. The decrease in blood volume of the experimental group was not significantly slowed compared to the control group as reported. Since that was the basis of this work, this flaw may shatter all resulting hemodynamic data measured by the PICCO method. The authors have been unable to determine the source of the error., (Copyright © 2018. Published by Elsevier Inc.)

Background/purpose: Appropriate patient selection for mechanical circulatory support following percutaneous coronary intervention (PCI) remains a challenge. This study aims to evaluate the role of coronary perfusion pressure and other left ventricular hemodynamics to predict cardiovascular collapse following PCI., Methods/materials: We retrospectively analyzed all patients who underwent PCI for acute coronary syndrome (ACS) from 2003 to 2016. Coronary perfusion pressure was calculated for each patient and defined as the difference in mean arterial pressure and left ventricular end diastolic pressure (LVEDP). Logistic regression analysis was performed to determine predictor of composite outcome of in-hospital mortality, myocardial infarction (MI), congestive heart failure (CHF), and cardiogenic shock., Results: Nine hundred twenty-two patients were analyzed. Two-hundred twenty-eight (25%) presented with ST-elevation MI (STEMI) while 694 (75%) underwent PCI for unstable angina or non-Q-wave MI. The mean LVEDP was significantly higher in the STEMI patients (24 ± 9 vs. 19 ± 8 mm Hg, p < 0.05) and perfusion pressure significantly lower (68 ± 24 vs. 74 ± 18 mm Hg, p < 0.05). Eighty-seven (9.4%) reached the composite endpoint, and there was no difference between the STEMI and Not-STEMI groups. Neither LVEDP nor coronary perfusion pressure was a predictor of the composite outcome following multivariable logistic regression analysis for either STEMI or Not-STEMI patients. Increasing age, chronic renal insufficiency (CRI), CHF, and low left ventricular ejection fraction were predictors of the composite outcome for Not-STEMI patients, whereas only history of cerebrovascular accident and CRI were predictors for STEMI patients., Conclusions: In hemodynamically stable patients presenting with ACS, LVEDP and coronary perfusion pressure are not predictive of in-hospital cardiovascular collapse., Summary: The authors retrospectively analyzed 922 patients from a single center who underwent percutaneous coronary intervention (PCI) for acute coronary syndromes to evaluate the role of coronary perfusion pressure and other left ventricular hemodynamics to predict cardiovascular collapse following PCI. They found that neither coronary perfusion pressure nor left ventricular end diastolic pressure was predictive of in-hospital cardiovascular collapse., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Delayed sternal closure (DSC) in patients with severely compromised preoperative hemodynamics can be helpful as the chest sometimes cannot be able to contain both lungs and heart. We report our experience to evaluate the midterm results of this strategy in an adult population., Materials and Methods: From May 2009 till July 2015, 33 patients had DSC as first treatment of severe hemodynamic deterioration after cardiac surgery. Surgical procedures were valvular (9.27%) or coronary artery bypass grafting + others (24.73%). Stepwise logistic regression (SLR) showed that patients with lower ejection fraction, dilated right ventricle, and severe pulmonary hypertension were more likely to need DSC. Patients were divided in two groups: group A ( n  = 17), when the sternum was reopened before any hemodynamic collapse, or was never closed, and group B ( n  = 16), when the sternum was reopened after hemodynamic collapse., Results: Inhospital mortality was 39% ( n  = 13), 18% in group A and 62% in group B ( p  < 0.0001). In 28 patients where the sternum was reopened, cardiac index increased from 1.7 (1.6, 1.9) L/m 2 to 2.8 (2.4, 3) L/m 2 , p  < 0.0001. The sternum was closed in 28 patients (85%), 94% in group A and 75% in group B ( p  = 0.13), after a median of 4 (2.5) days. SLR showed that only group B ( p  < 0.0001) was a risk factor for early death. Two-year survival was 48 ± 9%, higher in group A (71 ± 13) than in group B (25 ± 11), p  < 0.0001. Cox's analysis showed that group B ( p  < 0.0001) and redo ( p  < 0.0001) were risk factors for lower survival., Conclusion: Elective DSC represents a useful strategy in severely compromised patients, entailing an improvement of hemodynamics and a higher survival., Competing Interests: Prof. Antonio Maria Calafiore discloses that he is a consultant for Fehling Instruments GmbH & Co. KG, Karlstein, Germany., (Georg Thieme Verlag KG Stuttgart · New York.)

Candidates for percutaneous coronary revascularization are becoming progressively older and more complex. A combination of factors related to the patient, lesion, and/or hemodynamic conditions may increase the risk of adverse events. Therefore, when a high-risk procedure is identified, it is crucial to provide the patient with adequate support in order to safely perform percutaneous coronary intervention (PCI). We report the case of a 77-year-old man with moderate left ventricular dysfunction and stage IV chronic kidney disease who underwent successful recanalization of a chronically occluded left anterior descending artery. The procedure was performed with a micro-axial percutaneous left ventricular assist device (Impella 2.5) in order to provide stable hemodynamics, and with minimal contrast medium administration (14 ml) to minimize the risk of acute kidney injury. Despite the use of aggressive techniques (including rotational atherectomy), the patients remained stable throughout the procedure and did not experience contrast-induced nephropathy or periprocedural myocardial infarction, and was discharged two days later. Moreover, we provide recommendations to assist interventional cardiologist safely perform complex and high-risk PCI, with particular attention to renal function preservation., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Williams syndrome (WS) is a congenital, multisystem disorder affecting the cardiovascular, connective tissue, and central nervous systems in 1 in 10 000 live births. Cardiovascular involvement is the most common cause of morbidity and mortality in patients with WS, and noninvasive and invasive procedures are common. Sudden cardiovascular collapse in patients with WS is a well-known phenomenon, especially in the peri-procedural period. Detailed guidelines for peri-procedural management of patients with WS are limited. The goal of this review is to provide thoughtful, safe and effective management strategies for the peri-procedural care of patients with WS with careful consideration of hemodynamic impacts of anesthetic strategies. In addition, an expanded risk stratification system for anesthetic administration is provided., (© 2017 Wiley Periodicals, Inc.)

Few previous studies have monitored hemodynamic parameters to determine the physiological process of dengue or examined inferior vena cava (IVC) parameters to assess cardiac preload during the clinical phase of dengue. From January 2013 to July 2015, we prospectively studied 162 hospitalized adults with confirmed dengue viral infection using non-invasive cardiac output monitoring and bedside ultrasonography to determine changes in hemodynamic and IVC parameters and identify the types of circulatory shock that occur in patients with dengue. Of 162 patients with dengue, 17 (10.5%) experienced dengue shock and 145 (89.5%) did not. In patients with shock, the mean arterial pressure was significantly lower on day 6 after fever onset (P = 0.045) and the pulse pressure was significantly lower between days 4 and 7 (P<0.05). The stroke volume index and cardiac index were significantly decreased between days 4 and 15 and between days 5 and 8 after fever onset (P<0.05), respectively. A significant proportion of patients with dengue shock had an IVC diameter <1.5 cm and IVC collapsibility index >50% between days 4 and 5 (P<0.05). Hypovolemic shock was observed in 9 (52.9%) patients and cardiogenic shock in 8 (47.1%), with a median (interquartile range) time to shock onset of 6.0 (5.0-6.5) days after fever onset, which was the median day of defervescence. Intravascular hypovolemia occurred before defervescence, whereas myocardial dysfunction occurred on the day of defervescence until 2 weeks after fever onset. Hypovolemic shock and cardiogenic shock each occurred in approximately half of the patients with dengue shock. Therefore, dynamic measures to estimate changes in hemodynamic parameters and preload should be monitored to ensure adequate fluid therapy among patients with dengue, particularly patients with dengue shock.

We report a case of an 87-year-old female who underwent percutaneous coronary intervention (PCI) for non-ST elevation myocardial infarction while she was being worked up for transcatheter aortic valve procedure. Hemodynamic compromise occurred during the PCI, which could only be mitigated by doing a balloon aortic valvuloplasty and Impella™ insertion. This case report will help in preparedness for any untoward events in patients with aortic stenosis and undergoing percutaneous coronary intervention., (© 2015 Wiley Periodicals, Inc.)

Unlabelled: Shock is defined as a situation where oxygen transport is inadequate to meet the body's oxygen demand. An understanding of the mechanism(s) of reduced cardiac output, a determinant of oxygen transport, is crucial in order to initiate appropriate therapy to manage shock. Combining the concept of venous return with the ventricular pressure-volume relationship is a useful method to appreciate the complex circulatory physiology of shock. Clues from the patient's history, physical examination, and key laboratory tests, along with the careful inspection of hemodynamic, electrocardiographic and respiratory waveforms can help with the identification of the etiology and mechanism(s) of shock. Following verification of the arterial pressure, general resuscitation can begin, and more specific treatment can be undertaken to manage shock. If the patient is unresponsive to these measures, bedside ultrasound can then be performed to ascertain more detail regarding the mechanism(s) and etiology of shock., Purpose: To develop an approach to the management of the hemodynamically unstable patient., Principal Finding: Not applicable., Conclusion: Not applicable.

Cardiac rhabdomyomas are rare and often regress spontaneously. However, the management of rhabdomyoma with severe inflow and outflow obstructions is a challenge. An infant with a massive left ventricular rhabdomyoma mimicking the haemodynamics of hypoplastic left heart syndrome is reported. Surgery could not be contemplated because the mitral valve leaflets and chordae were imbedded in the tumour mass. The arterial duct (AD) was kept open to perfuse the systemic circulation and palliations with pulmonary artery branch banding and AD stenting were planned. However; while waiting for spontaneous regression of the tumour, the child died of circulatory collapse when 4 weeks old.

Introduction: The military recommends that a 500 mL bolus of Hextend® be administered via an intravenous (IV) 18-gauge needle or via an intraosseous (IO) needle for patients in hypovolemic shock., Purposes: The purposes of this study were to compare the time of administration of Hextend and the hemodynamics of IV and IO routes in a Class II hemorrhage swine model., Methods: This was an experimental study using 27 swine. After 30% of their blood volume was exsanguinated, 500 mL of Hextend was administered IV or IO, but not to the control group. Hemodynamic data were collected every 2 minutes until administration was complete., Results: Time for administration was not significant (p=.78). No significant differences existed between the IO and IV groups relative to hemodynamics (p>.05), but both were significantly different than the control group (p<.05)., Conclusions: The IO route is an effective method of administering Hextend., (2014.)

Objective: Neurogenic shock considered a distributive type of shock secondary to loss of sympathetic outflow to the peripheral vasculature. In this study, we examine the hemodynamic profiles of a series of trauma patients with a diagnosis of neurogenic shock., Methods: Hemodynamic data were collected on a series of trauma patients determined to have spinal cord injuries with neurogenic shock. A well-established integrated computer model of human physiology was used to analyze and categorize the hemodynamic profiles from a system analysis perspective. A differentiation between these categories was presented as the percent of total patients., Results: Of the 9 patients with traumatic neurogenic shock, the etiology of shock was decrease in peripheral vascular resistance (PVR) in 3 (33%; 95% confidence interval, 12%-65%), loss of vascular capacitance in 2 (22%; 6%-55%) and mixed peripheral resistance and capacitance responsible in 3 (33%; 12%-65%), and purely cardiac in 1 (11%; 3%-48%). The markers of sympathetic outflow had no correlation to any of the elements in the patients' hemodynamic profiles., Conclusions: Results from this study suggest that hypotension of neurogenic shock can have multiple mechanistic etiologies and represents a spectrum of hemodynamic profiles. This understanding is important for the treatment decisions in managing these patients., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Objectives: The aim of this study was to assess the association of hemodynamic factors with 90-day mortality in critically ill patients with severe acute pancreatitis (SAP)., Methods: One hundred fifty-nine consecutive patients with SAP admitted to the intensive care units between January 2005 and December 2008 were included in study. We assessed the association of hemodynamic variables during the first 24 hours in the intensive care unit with 90-day mortality using multivariate analysis for all patients with SAP and for a subgroup with circulatory shock., Results: Advanced age (odds ratio [OR], 1.09; 95% confidence interval, 1.04-1.15 per year), higher serum creatinine (OR, 1.01; 95% confidence interval, 1.00-1.02 per unit), and lower mean arterial pressure (OR, 0.92; 95% confidence interval, 0.86-0.99 per mm Hg) were independently associated with 90-day mortality. In the subgroup of SAP with shock, higher Acute Physiology and Chronic Health Evaluation II score (OR, 1.15; 95% confidence interval, 1.00-1.32 per point), higher central venous pressure (OR, 1.25; 95% confidence interval, 1.03-1.52 per mm Hg), and lower cardiac index (OR, 0.33; 95% confidence interval, 0.11-0.98 per L/min per m²) were independent risk factors for 90-day mortality., Conclusions: Advanced age, higher serum creatinine, and lower mean arterial pressure are associated with 90-day mortality in patients with SAP. In the subgroup of patients with SAP and shock, higher Acute Physiology and Chronic Health Evaluation II score, higher central venous pressure, and lower cardiac index predicted 90-day mortality.

Aim: The aim of this study was to validate the classification of hypovolaemic shock given by the Advanced Trauma Life Support (ATLS)., Methods: Patients derived from the TraumaRegister DGU(®) database between 2002 and 2010 were analyzed. First, patients were allocated into the four classes of hypovolaemic shock by matching the combination of heart rate (HR), systolic blood pressure (SBP) and Glasgow Coma Scale (GCS) according to ATLS. Second, patients were classified by only one parameter (HR, SBP or GCS) according to the ATLS classification and the corresponding changes of the remaining two parameters were assessed within these four groups. Analyses of demographic, injury and therapy characteristics were performed as well., Results: 36,504 patients were identified for further analysis. Only 3411 patients (9.3%) could be adequately classified according to ATLS, whereas 33,093 did not match the combination of all three criteria given by ATLS. When patients were grouped by HR, there was only a slight reduction of SBP associated with tachycardia. The median GCS declined from 12 to 3. When grouped by SBP, GCS dropped from 13 to 3 while there was no relevant tachycardia observed in any group. Patients with a GCS=15 presented normotensive and with a HR of 88/min, whereas patients with a GCS<12 showed a slight reduced SBP of 117mmHg and HR was unaltered., Conclusion: This study indicates that the ATLS classification of hypovolaemic shock does not seem to reflect clinical reality accurately., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Purpose of Review: Circulatory abnormalities in cirrhosis include hyperdynamic circulation and cirrhotic cardiomyopathy. The extent of circulatory abnormalities is further exaggerated in acute-on-chronic liver failure (ACLF). The mechanism remains unclear and management also needs to be evaluated., Recent Findings: The predominant mechanism of ACLF is thought to be a systemic inflammatory reaction. Cardiovascular-active factors such as tumor necrosis factor and nitric oxide are increased and cortisol is decreased; the former further dilates the vasculature and the latter decreases the sensitivity to vasoconstrictors. The exaggerated vasodilatation further decreases the cardiac afterload. However, no study has yet demonstrated the benefit of vasodilators/vasoconstrictors in the management of ACLF. Standard medical treatment in this setting is associated with high mortality. Patients treated with molecular adsorbent recirculating system (MARS) had improved serum levels of inflammatory mediators such as tumor necrosis factor alpha and interleukin-6, but this was not associated with improved survival. Liver transplantation eventually reverses the cardiovascular abnormalities., Summary: Circulatory abnormalities are exaggerated in ACLF. The predominant mechanism is a systemic inflammatory reaction. Modalities such as MARS improve serum markers of inflammation, but not survival. Liver transplantation is the definitive treatment of the cardiovascular abnormalities of ACLF.

Objective: Acute pneumonitis with acute lung injury is a cause of significant mortality related to the 2009 pH1N1 influenza A virus. Widespread lung inflammation and increased pulmonary vascular permeability has been noted on autopsy. Also, many of these patients present with significant hemodynamic compromise suggesting systemic cytokine release. Therefore, attenuating circulating cytokines, and other mediators, by blood purification techniques is a theoretically attractive strategy. We report the use therapeutic plasma exchange in three children with 2009 H1N1 related acute lung injury with severe hemodynamic compromise that had failed conventional therapeutic interventions., Design: Case series., Setting: Pediatric intensive care unit in a university children's hospital., Patients: Three children, aged 8, 11, and 17 yrs, with acute respiratory distress syndrome and hemodynamic compromise related to the 2009 pH1N1 influenza A virus documented by polymerase chair reaction. All patients were on mechanical ventilation and inhaled nitric oxide, and one patient was on extracorporeal membrane oxygenation. Therapeutic plasma exchange was used as a rescue strategy., Interventions: Each patient received three exchanges of 35-40 mL/kg on consecutive days., Measurements: All three patients had dramatic reduction in pediatric logistic organ dysfunction scores, oxygen requirements, and vasopressor requirements after two exchanges. All survived with good functional recovery., Main Results: In this small series of patients with H1N1/acute respiratory distress syndrome and hemodynamic compromise, therapeutic plasma exchange appeared to benefit as a method of mitigating the associated cytokine storm. The procedure was well tolerated with no reported side effects. All three patients survived, defying the predicted mortality. Because these procedures used the filtration exchange method, it was performed in a timely fashion by intensive care unit personnel and on equipment already available in the intensive care unit for renal support., Conclusions: This very limited case series suggest there may be a role for therapeutic plasma exchange as a rescue therapy in severe shock and acute lung injury related to pH1N1 that has not responded to traditional therapy.

Objective: In the cancer population, pericardial effusions are a common and potentially life-threatening occurrence. Although decompression benefits most patients, paradoxical hemodynamic instability (PHI) develops in some, with hypotension and shock in the immediate postoperative period. This study examines paradoxical hemodynamic instability after pericardial window and identifies prognostic factors in patients with cancer who are treated for pericardial effusion., Methods: Retrospective review of 179 consecutive pericardial windows performed for pericardial effusion in a tertiary cancer center over a 5-year period (January 2004 through March 2009). Demographic, surgical, pathologic, and echocardiographic data were analyzed for the end points of paradoxical hemodynamic instability (pressor-dependent hypotension requiring intensive care unit admission) and overall survival., Results: The most common malignancies were lung (44%), breast (20%), hematologic (10%), and gastrointestinal (7%). Overall survival for the group was poor (median, 5 months); patients with hematologic malignant disease fared significantly better than the others (median survival 36 months; P = .008). Paradoxical hemodynamic instability occurred in 19 (11%) patients. These patients were more likely to have evidence of tamponade on echocardiogram (89% vs 56%; P = .005), positive cytology/pathology (68% vs 41%; P = .03), and higher volume drained (674 mL vs 495 mL; P = .003). Overall survival was significantly shorter in those in whom paradoxical hemodynamic instability developed (median survival 35 vs 189 days; hazard ratio = 3; P < .001), and the majority of them (11/19, 58%) did not survive their hospitalization., Conclusions: Postoperative hemodynamic instability after pericardial window portends a grave prognosis. Evidence of tamponade, larger effusion volumes, and positive cytologic findings may predict a higher risk of paradoxical hemodynamic instability and anticipate a need for invasive monitoring and intensive care postoperatively., (Copyright © 2011 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.)

The purpose of the research is t objectify the indications for use of catecholamines and/or change of the infusion therapy volume based on transpulmonary thermodilution in children with severe traumatic injuries. The examined group consisted of 22 children with thermal concomitant or isolated trauma and drowning. All the patents were transferred to the Intensive Care Unit from other hospitals. Hemodynamic parameter estimation was based upon transpulmonary thermodilution. Results indicate, that based upon dynamic assessment of cardiac output, preload (global end diastolic volume index) and postload (systemic vascular resistance index) it is possible to carry out an early targeted correction of the fluid therapy and chose the right type of inotorpic support. Transpulmonary thermodilution in children with severe traumatic injuries allows achieving optimal parameters of blood circulation just 24 hours after its adaption.

Extracorporeal membrane oxygenation (ECMO) is an important circulatory assist for children with refractory cardiopulmonary dysfunction, but its role and indications after a stage 1 Norwood procedure are controversial. We assessed outcomes and risk factors in patients who underwent a Norwood palliation and ECMO at our institution. We retrospectively reviewed all patients who underwent a Norwood procedure and were supported with ECMO between January 1998 and January 2010. Of the 91 children who underwent a Norwood procedure during the study period, there were 15 postoperative runs of ECMO in 12 patients. The diagnoses of the patients included five with hypoplastic left heart syndrome, five with a hypoplastic left heart syndrome variant, and two with critical aortic stenosis. A total of four patients underwent bilateral pulmonary artery banding, and two patients underwent aortic valvuloplasty before the stage 1 Norwood procedure. The mean age of the patients was 28±30 days, and mean body weight was 2.6±0.5kg at the induction of ECMO. The indications for ECMO were low cardiac output in six children, circulatory collapse needing cardiopulmonary resuscitation in six children, and hypoxemia in three children. Five of the 12 patients were successfully weaned from ECMO. The significant risk factors for the inability to be weaned from ECMO were a history of circulatory collapse requiring cardiopulmonary resuscitation, and the induction of ECMO in the intensive care unit. Induction of ECMO may be considered earlier when hemodynamics are unstable in impaired patients following a stage 1 Norwood procedure to avoid circulatory collapse., (© 2010, Copyright the Authors. Artificial Organs © 2010, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.)

Sepsis is the systemic inflammatory response syndrome secondary to a local infection, and severe sepsis and septic shock are the more devastating scenarios of this disease. In the last decade, considerable achievements were obtained in sepsis knowledge, and an international campaign was developed to improve the treatment of this condition. However, sepsis is still one of the most important causes of death in intensive care units. The early stages of sepsis are characterized by a variety of hemodynamic derangements that induce a systemic imbalance between tissue oxygen supply and demand, leading to global tissue hypoxia. This dysfunction, which may occur in patients presenting normal vital signs, can be accompanied by a significant increase in both morbidity and mortality. The early identification of high-risk sepsis patients through tissue perfusion markers such as lactate and venous oxygen saturation is crucial for prompt initiation of therapeutic support, which includes early goal-directed therapy as necessary. The purpose of this article was to review the most commonly used hemodynamic and perfusion parameters for hemodynamic optimization in sepsis, emphasizing the physiological background for their use and the studies that demonstrated their effectiveness as goals of volemic resuscitation.

Background: Refractory hypotension is a frequent event during reperfusion of a liver graft. Measures that help maintain hemodynamic stability include correction of electrolytes and acid-base abnormalities as well as administration of fluid and/or catecholamines. Vasoplegic syndrome represents the most severe form of hemodynamic instability. Management of this condition is very difficult due primarily to the inadequate response to even very high doses of catecholamines., Case Report: A 60-year-old patient presented for liver transplantation due to end stage liver disease. After an initially uneventful hepatic phase, the patient developed excessive tachycardia and refractory hypotension during cross-clamping of the vena cava. The situation rapidly deteriorated despite administration of fluid and extremely high doses of norepinephrine and vasopressin. A transesophageal echocardiogram (TEE) performed at that time failed to demonstrate any cardiac dysfunction or signs of pulmonary emboli. Subsequent blood cultures and imaging studies did not confirm any signs of sepsis. Further investigation revealed an increased preoperative level of cyclic guanosine monophosphate (cGMP). cGMP is the second messenger for nitric oxide, and is responsible for relaxation of vascular smooth muscle with subsequent vasodilatation. This finding suggests a release of nitric oxide in the systemic circulation which could have been a potential cause for vasoplegic shock., Conclusions: Release of nitric oxide in the systemic circulation can be a potential cause of vasoplegic syndrome. Future investigation will demonstrate whether a patient's preoperative cGMP plasma level can be a potential predictor of intraoperative hemodynamic instability.

Background: In patients with ruptured abdominal aortic aneurysm (RAAA) and shock, the time lag between the onset of the symptoms due to RAAA and the presence of a full developed shock syndrome was evaluated to assess its prognostic meaning. This time lag was called time before shock (TBS)., Methods: Ninety-four patients operated on between 2002 and 2007 have been retrospectively analyzed regarding TBS and the following parameters: presence of shock, severity of bleeding, age, comorbidities, and gender. According to TBS, on a 10-hour cutoff value, three groups of patients were distinguished: patients with TBS of 10 or less (short TBS), patients with TBS greater than 10 (long TBS), and patients without shock. The relationship of these variables with intraoperative and 30-day mortality was analyzed by both univariate and multivariate analyses., Results: In the univariate analysis, patients with short TBS presented with four-fold mortality compared to patients without shock (p=0.000), whereas the increase in mortality of the patients with long TBS was nonsignificant (p=0.448). The mortality in patients with shock (presence of shock) was 3.7 times higher than in patients without shock (p=0.001). The mortality related to massive bleeding was 3.7 times higher than that associated with moderate bleeding (p=0.001). An increased mortality with borderline significance level was observed in patients older than 75 years (p=0.052). The relationship of mortality to the presence of comorbidities and gender was not significant. In the multivariate analysis, the mortality among the patients with short TBS was clearly highest, after either massive or moderate bleeding. In the logistic model with TBS, the Wald test showed as significant both short TBS (p=0.001) and severity of bleeding (p=0.033) but not age (p=0.103) and long TBS (p=0.0401). The model with TBS presented a better performance than that with shock, showing higher sensitivity, higher values of Youden's J, and a greater proportion of the total variation in mortality. Through the model with TBS, two groups of patients (those 75 years or younger with massive bleeding and those older than 75 years with moderate bleeding), both with short TBS, presented with a high risk of death not predicted by the model with shock., Conclusion: TBS seems to complete the information given by the parameter "presence of shock," and its evaluation allows a more effective judgment of the risk of death, at emergency admission of patients with RAAA., (Copyright (c) 2010. Published by Elsevier Inc.)

Background: Right ventricular myocardial infarction (RVMI) is the major cause of hypotension and/or shock (HpS) after acute inferior myocardial infarction (inferior AMI). It is, however, unclear how RVMI affects the acute hemodynamic course., Methods and Results: In the present study, 153 patients with inferior AMI caused by right coronary artery occlusion were examined. Associations between in-hospital outcome and HpS before admission (preER-HpS) or HpS after admission (postER-HpS) were assessed using multivariate logistic regression analysis. Multivariate analysis was also conducted to determine a predictor for postER-HpS, including clinical findings in the emergency room as independent variables. HpS developed in 48.4% of patients with inferior AMI. Patients with RVMI more frequently had HpS than their counterparts in the first 6 h after infarction onset. RVMI was, however, not associated with preER-HpS, but was independently with postER-HpS (odds ratio (OR): 10.1; 4.0-27.7), whereas left ventricular failure was associated with preER-HpS, but not with postER-HpS. Furthermore, RVMI (OR: 9.4; 3.6-27.1) identified at presentation predicted postER-HpS., Conclusions: Independent of concomitant left ventricular involvement, RVMI was significantly associated with postER-HpS, but not with preER-HpS. These findings highlight the importance of identifying RVMI immediately after admission in the setting of inferior AMI. (Circ J 2010; 74: 148 - 155).

Objectives: To appraise the impact of AngioJet rheolytic thrombectomy (RT) on angiographic and clinical endpoints in patients with acute pulmonary embolism (PE)., Background: The management of patients with acute PE and hemodynamic compromise, based mainly on anticoagulant and thrombolytic therapies, is challenging and still suboptimal in many patients. In such a setting, mechanical removal of thrombus from pulmonary circulation holds the promise of significant clinical benefits, albeit remains under debate., Methods: We retrospectively report on 51 patients referred to our catheterization laboratory and treated with AngioJet RT. Patients were classified according to the degree of hemodynamic compromise (shock, hypotension, and right ventricular dysfunction) to explore thoroughly the degree of angiographic pulmonary involvement (angiographic massive PE was defined as the presence of a Miller index >or= 17) and the impact on angiographic (obstruction, perfusion, and Miller indexes) and clinical (all-cause death, recurrence of PE, bleeding, renal failure, and severe thrombocytopenia) endpoints of AngioJet RT., Results: Angiographic massive PE was present in all patients with shock, whereas patients with right ventricular dysfunction and hypotension showed a similar substantial pulmonary vascular bed involvement. Technical success was obtained in 92.2% of patients, with a significant improvement in obstruction, perfusion and Miller indexes in each subgroup (all P < 0.0001). Four patients reported major bleedings and eight (15.7%) died in-hospital. Laboratory experience was significantly associated to a lower rate of major bleedings. All survivors were alive at long-term follow-up (35.5 +/- 21.7 months) except three who expired due to cancer and acute myocardial infarction., Conclusions: In experienced hands AngioJet RT can be operated safely and effectively in most patients with acute PE, either massive or submassive, and substantial involvement of pulmonary vascular bed., ((c) 2009 Wiley-Liss, Inc.)

We report a case of hemodynamic collapse during pulmonary embolectomy with cardiopulmonary bypass. The hemodynamic collapse was due to complete loss of venous return due to thromboembolic occlusion of the atrial cannula. The diagnosis was made during focused intraoperative transesophageal echocardiography.

The controversy surrounding the use of the pulmonary artery catheter, has stimulated research into alternative methods of haemodynamic monitoring. As yet, however, no new gold standard has emerged. In the future, interest in haemodynamic monitoring is likely to focus more on tissue perfusion and metabolism instead of central circulation. Important causes of shock in the ICU, apart from acute blood loss, are sepsis and acute heart failure. Septic shock results from vasodilatation and myocardial dysfunction. Early initiation of aggressive fluid resuscitation, if necessary accompanied by vasoactive and inotropic agents, improves survival. In addition, low dose corticosteroids have a positive impact on mortality. In the treatment of patients with acute heart failure, phosphodiesterase III-inhibitors are becoming part of standard therapy in addition to beta-adrenoceptor agonists, especially in patients who take beta-blockers.

Background: The causes of hemodynamic collapse during off-pump coronary artery bypass (OPCAB) remain scarcely defined. We present an analysis of 23 cases of sustained hemodynamic collapse during elective off-pump CABG., Methods: During a 54-month period, we performed 1420 elective OPCAB procedures through a sternotomy, constituting 71.2% of the total CABG procedures performed. Twenty-three patients (1.6%) experienced hemodynamic collapse intra-operatively requiring immediate cardiopulmonary bypass. Preoperative characteristics, intraoperative data, and postoperative outcome were retrospectively reviewed in each patient., Results: In all cases, improvements in intra-operative technique and/or judgment could be made retrospectively. Twenty (20/23) of these patients had an uneventful postoperative course and three (3/23) patients had an unstable course with two deaths., Conclusions: The causes of hemodynamic collapse during elective OPCAB were ischemic, mechanical, or a combination of both. A detailed review of our five and a half year experience has revealed a number of suggestions for improving the conduct of the operation.

Objective: Arginine-vasopressin (AVP) might be a potent vasopressor agent in catecholamine-resistant postcardiotomy shock. However, its use remains experimental because of considerations about deleterious effects on the heart. We report on the effects of continuous AVP-infusion on cardiac performance, biomarkers of myocardial ischemia, and systemic hemodynamics in catecholamine-resistant postcardiotomy shock., Design: Retrospective study., Setting: Twenty-one-bed general and surgical intensive care unit., Patients: Forty-one patients with catecholamine-resistant postcardiotomy shock., Interventions: Continuous infusion of AVP., Measurements and Results: Heart rate (HR), heart rhythm, mean arterial pressure (MAP), central venous pressure, mean pulmonary arterial pressure, cardiac index (CI), stroke volume index (SVI), left ventricular stroke work index (LVSWI), systemic vascular resistance (SVR) as well as milrinone and norepinephrine requirements were collected before and 1, 4, 12, 24, and 48 h after start of AVP infusion. Creatine kinase MB and troponin-I serum concentrations were measured daily. During AVP administration we observed a significant decrease in HR (-14.8%), milrinone (-17.5%), and norepinephrine requirements (-54.9%) as well as biomarkers of cardiac ischemia and a significant increase in LVSWI (+46.2%), MAP (+41.8%) and SVR (+60%). CI and SVI remained unchanged. Forty-five percent of postoperative new-onset tachyarrhythmias (TA) converted into sinus rhythm during AVP infusion., Conclusions: AVP was devoid of adverse effects on the heart in these patients with catecholamine-resistant postcardiotomy shock. The significant reduction in HR, vasopressor, and inotropic support suggest a substantial improvement in myocardial performance. These findings are supported by a significant decrease of cardiac enzymes and cardioversion of TA into sinus rhythm in 45.5% of patients with new-onset TA.

To elucidate one way of the shock mechanisms, the hemodynamic alterations were examined in 7 dogs with heartworm (HW) extract-induced shock. The first alteration observed after injection of HW extract was a decrease in right ventricular end-diastolic pressure (RVEDP). After that, left ventricular (LV) end-diastolic pressure, LV systolic pressure, and LV dp/dt fell significantly, followed by a decrease in the cardiac output of all dogs to below the detectable level (1.00 l/min). Since RVEDP depends on blood flow into the right ventricle, the decrease in RVEDP means a reduction in venous return. Therefore, this study showed that the first trigger of a decrease in blood pressure in HW extract-induced shock is the reduction in venous return.

We studied the effect of abrupt discontinuation of inhaled nitric oxide (iNO) in patients receiving this drug for treatment of acute hypoxemic respiratory failure (AHRF), in order to determine the need for continued therapy, the incidence and nature of adverse events, and the risk factors predicting these adverse events. Thirty-one patients who showed an initial increase in Pa(O(2)) of > 20 mm Hg in response to iNO underwent a discontinuation trial at 10 to 30 h after beginning iNO. Indwelling arterial and pulmonary artery catheters facilitated monitoring of hemodynamic and gas-exchange parameters. For the group, discontinuation of iNO caused a significant decrease in Pa(O2 ), arterial and mixed venous oxygen saturation, and ratio of Pa(O(2)) to fraction of inspired oxygen (FI(O(2))). Three patterns of response were observed. Eight of 31 (25.8%) patients had minimal changes in oxygenation or hemodynamics, suggesting no need for ongoing therapy. Fifteen of 31 (48%) patients had worsened gas exchange as a predominant response. Eight of 31 patients exhibited hemodynamic collapse, defined as > 20% fall in cardiac output and/or mean arterial blood pressure. In this last subgroup, the pattern of cardiovascular changes suggested that this response arose from an acute increase in right ventricular afterload, and was not a consequence of gas-exchange abnormalities. In all cases, reinstitution of iNO promptly reversed worsened hemodynamics and gas exchange. Independent factors associated with an increased risk of cardiovascular collapse included multisystem organ failure, older age, and initial blood pressure increase in response to iNO; a smaller change in the ratio of Pa(O(2)) to FI(O(2)) with initiation of iNO therapy also tended to correlate with this phenomenon. We conclude that careful and monitored discontinuation of iNO in patients with AHRF will identify substantial fractions of patients who are either receiving no benefit from this therapy or who require iNO to maintain an adequate circulation and are therefore at risk for adverse outcome with transport or inadvertent discontinuation of iNO. Future trials of iNO should recognize this complication of such therapy and include assessments for it.

Sustained whole-body exposure of anesthetized rats to 35-GHz radio frequency radiation produces localized hyperthermia and hypotension, leading to circulatory failure and death. The physiological mechanism underlying the induction of circulatory failure by 35-GHz microwave (MW) heating is currently unknown. We hypothesized that oxidative stress may play a role in the pathophysiology of MW-induced circulatory failure and examined this question by probing organs for 3-nitrotyrosine (3-NT), a marker of oxidative stress. Animals exposed to low durations of MW that increased colonic temperature but were insufficient to produce hypotension showed a 5- to 12-fold increase in 3-NT accumulation in lung, liver, and plasma proteins relative to the levels observed in control rats that were not exposed to MW. 3-NT accumulation in rats exposed to MW of sufficient duration to induce circulatory shock returned to low, baseline levels. Leukocytes obtained from peripheral blood showed significant accumulation of 3-NT only at exposure levels associated with circulatory shock. 3-NT was also found in the villus tips and vasculature of intestine and within the distal tubule of the kidney but not in the irradiated skin of rats with MW-induced circulatory failure. The relationship between accumulation in liver, lung, and plasma proteins and exposure duration suggests either that nitro adducts are formed in the first 20 min of exposure and are then cleared or that synthesis of nitro adducts decreases after the first 20 min of exposure. Taken together, these findings suggest that oxidative stress occurs in many organs during MW heating. Because nitration occurs after microwave exposures that are not associated with circulatory collapse, systemic oxidative stress, as evidenced by tissue accumulation of 3-NT, is not correlated with circulatory failure in this model of shock.

Shock is a syndrome of numerous etiologies. The treatment of shock syndrome depends on the etiology and circulatory pathophysiology. From the viewpoint of circulatory physiology, the mechanism of circulatory failure can be attributed to three factors: blood volume; cardiac contractility; and vascular resistance. Balloon-tipped pulmonary artery (Swan-Ganz) catheters can distinguish between these factors in the clinical setting and allows physicians to treat shock patients most appropriately and logically. The author proposes a treatment-oriented classification of shock based on Swan-Ganz catheter findings and divides shock into three types: hypovolemic; cardiogenic; and low-resistant shock. All clinicians who treat shock must have qualified knowledge of and experience in handling this beneficial but invasive monitoring device.

Objectives: To document the effects of dobutamine on standard hemodynamics and right ventricular (RV) performance in patients exhibiting pulmonary edema following severe scorpion envenomation, and to characterize the tissue oxygenation profile in patients sustaining scorpion envenomation-related shock., Design: Prospective cohort study., Setting: An ICU in a university hospital., Patients: Nineteen consecutive patients were admitted to the ICU for severe scorpion envenomation; all 19 patients exhibited hemodynamic pulmonary edema, and 10 patients had peripheral shock., Interventions: All patients underwent a hemodynamic study with a Swan-Ganz catheter. In 8 of 19 patients, the thermodilution catheter was equipped with a fast-response thermistor., Measurements and Results: Standard hemodynamic parameters were recorded on admission and following the infusion of dobutamine in all patients at a dosage, from 7 to 20 microg/kg/min, intended to achieve the best hemodynamic and tissue oxygenation compromise. RV ejection fraction (RVEF) and RV volumes were simultaneously recorded in 8 patients, and tissue oxygenation parameters were assessed in the 10 patients with peripheral shock. The clinical signs of tissue hypoperfusion improved, and optimal hemodynamic parameters were achieved at a mean +/- SD dobutamine dosage of 17 +/- 7 microg/kg/min. Dobutamine infusion evoked statistically significant increases in cardiac index, from 2.3 +/- 0.6 to 3.6 +/- 0.7 L/min/m2; stroke volume index, from 18 +/- 5 to 31 +/- 10 mL/m2; and systemic arterial pressure, from 64 +/- 12 to 78 +/- 14 mm Hg. Pulmonary artery occlusion pressure (PAOP) and venous admixture decreased significantly: from 23 +/- 4 to 15 +/- 6 mm Hg and from 29 +/- 7% to 20 +/- 5%, respectively. With respect to RV function, dobutamine infusion significantly increased the RVEF, from 24 +/- 7% to 42 +/- 9%, without significantly changing the RV end-diastolic volume index, reflecting an enhanced RV contractility. In patients with peripheral circulatory failure, the baseline tissue oxygenation profile was consistent with cardiogenic shock, showing increased oxygen extraction as a consequence of a striking depression in oxygen delivery (DO2). After dobutamine infusion, DO2 improved significantly, from 386 +/- 104 to 676 +/- 156 mL/min/m2, with a significant decrease in oxygen extraction, from 34 +/- 8% to 24 +/- 6%., Conclusions: In severe scorpion envenomation, dobutamine infusion improves impaired heart function. The effects involve both left ventricular and RV dysfunction. Impaired tissue oxygenation is also improved.

Background: Upper gastrointestinal endoscopy in the elderly is increasingly becoming more common, despite the possibility that a minimal load on the circulation can cause serious complications such as shock and cardiac arrest., Objective: The effects of endoscopy on the heart and the possibility of predicting circulatory accidents were studied using natriuretic peptide levels., Methods: The patients were randomly chosen according to their age and divided into an elderly group (over 60 years of age, 64 patients) and a young group (under 30 years of age, 20 patients). The patients in the elderly group were further subdivided into two groups based on the presence or absence of circulatory complications (46 patients with circulatory complications and 18 without complications). The load on the heart was evaluated by measuring human atrial natriuretic peptide (hANP) and human brain natriuretic peptide (hBNP) which are secreted by the myocardial cells in response to cardiac load. Specimens were obtained before and after endoscopy., Results: The hANP level was significantly higher after endoscopy in the elderly group, regardless of the presence or absence of circulatory complications. No significant difference was observed in the hBNP level. No significant increase in hANP or hBNP levels was observed after endoscopy in the young group., Conclusions: These observations suggest an increased atrial load during endoscopy in the elderly. The increase in pulse rate during endoscopy is one possible cause of atrial load. Therefore, the risk of circulatory system damage must be recognized when endoscopy is performed in the elderly. The measurement of plasma hANP and hBNP levels may provide effective indices for evaluating cardiac load during endoscopy.

Objective: To assess the hemodynamic effects of fluid loading in patients with acute circulatory failure caused by acute massive pulmonary embolism (AMPE)., Design: Prospective study., Setting: Respiratory critical care unit of a university hospital., Patients: Thirteen patients free of previous cardiopulmonary disease with angiographically proven AMPE (Miller index = 24 +/- 1), with acute circulatory failure defined by a cardiac index (CI) lower than 2.5 L/min/m2., Intervention: Infusion of 500 mL of dextran 40 over 20 mins., Measurements and Main Results: Fluid loading induced a substantial increase in right atrial pressure from 9 +/- 1 mm Hg to 17 +/- 1 mm Hg and in right ventricular end-diastolic volume index from 123 +/- 14 mL/m2 to 150 +/- 11 mL/m2 (p < .05 for both comparisons). The increase in right ventricular preload was associated with an increase in Cl from 1.6 +/- 0.1 to 2.0 +/- 0.1 L/min/m2 (p < .05), whereas right ventricular ejection fraction (15 +/- 3% at baseline vs. 16 +/- 3% after fluid loading) and total pulmonary vascular resistance index (1689 +/- 187 dyne x sec/cm5 x m2 at baseline vs. 1492 +/- 166 dyne x sec/ cm5 x m2 after fluid loading) remained unchanged. The increase in Cl induced by fluid loading was inversely correlated to baseline right ventricular end-diastolic volume index (r = -.89 ; p< .05)., Conclusions: These results suggest that fluid loading can improve hemodynamic status in patients with acute circulatory failure caused by AMPE.

Objective: Diaspirin cross-linked hemoglobin (DCLHb) is a vasoactive hemoglobin-based oxygen carrier or "blood substitute" that has been shown to improve base deficit in several experimental studies of hemorrhagic shock. Our objective was to determine if the addition of DCLHb to the resuscitation regimen would improve hemodynamic parameters, metabolic acidosis, and survival in our rat burn shock model compared with currently used resuscitation therapy., Methods: This was a randomized, controlled, experimental rat study. Male Wistar rats, weighing 200 to 250 g, were surgically prepared for an acute study. After placement of indwelling catheters, baseline hemodynamic values (mean arterial pressure, cardiac output, systemic vascular resistance, stroke volume, and base excess) were obtained. Thirty-two rats were used in the study, and they were either subjected to a 30% scald burn (experimental group) or sham burned (control group). The experimental animals were immediately intravenously resuscitated and followed for 6 hours. The resuscitation was based on the Parkland formula (4 mL/kg for each 1% of total body surface area [TBSA] burn), with 50% of the calculated fluid amount to be administered at a constant rate during the first 8 hours after burn. The animals were resuscitated for 6 hours and received between 9.00 and 11.25 mL of fluid depending on weight. The experimental animals were randomly assigned to one of three treatment groups: group I, lactated Ringer's solution; group II, lactated Ringer's solution-human serum albumin; group III, lactated Ringer's solution-DCLHb. Group I (n = 8) received 4 mL/kg lactated Ringer's solution for each 1% of TBSA burn. Group II (n = 8) received 2 mL/kg lactated Ringer's solution and 2 mL/kg human serum albumin for each 1% of TBSA burn. Group III (n = 8) received 2 mL/kg lactated Ringer's solution and 2 mL/kg DCLHb for each 1% of TBSA burn. The sham group (n = 8) was not burned and was not resuscitated. Animals that survived up to 6 six hours were killed., Results: We found that mean arterial pressure, cardiac output, stroke volume, and base excess were all improved in the DCLHb-lactated Ringer's solution-treated animals compared with the other experimental treatment groups. The 6-hour mortality rates were zero of eight (lactated Ringer's solution-DCLHb group), zero of eight (sham group), three of eight (lactated Ringer's solution-human serum albumin group), and six of eight (lactated Ringer's solution only group)., Conclusion: Early resuscitation with DCLHb is superior to non-oxygen-carrying resuscitative fluids in improving hemodynamics and survival in this model of burn shock. DCLHb might improve general tissue perfusion in the acute postburn period, and it could be useful in the early management of patients with severe burns.

During endotoxin shock mean arterial pressure (MAP) and cardiac output (CO) fall, and the latter is redistributed. To evaluate whether these changes are solely caused by the low output, or are also based on endotoxin itself, we compared regional hemodynamic changes during endotoxemia with those in a nonendotoxemic state of decreased CO in anesthetized rats. In group E (n = 10) endotoxin Escherichia coli O127:B8 (8 mg.kg-1) was infused from t = 0 till t = 60 min. In group B (n = 10) the same decrease of CO and MAP was obtained as in group E by inflating a balloon in the inferior caval vein, distal to the renal veins, from t = 0 till t = 60 min. We measured MAP, CO (thermodilution), central venous pressure, heart rate, organ blood flow, and redistribution of CO (microspheres), arterial lactate and glucose, and hematocrit. MAP and CO decreased (p < .05) in both groups (by 30 and 50%, respectively at t = 60). Heart rate, hematocrit, arterial lactate, and arterial glucose were significantly higher (p < .05) in group E (by 17, 12, 180, and 55%, respectively). Blood flow to most organs had similarly decreased in both groups. The decreased intestinal blood flow lead to macroscopic damage only in group E. Blood flows (absolute or as percentage of CO) to heart, hepatic artery, and diaphragm, however, had significantly increased in group E while blood flows to skin, skeletal muscle, and stomach had decreased more in group E. Except for the heart these differences could be explained by increased work load (detoxification: liver; hyperventilation: diaphragm, muscle) and thus to a more pronounced redistribution at the expense of skin and muscle blood flow. Regional hemodynamic changes during endotoxemia thus could largely be attributed to decrease of CO and redistribution of the circulating blood volume. In the heart, endotoxin seemed to exert effects independent of the hypodynamic state. This was also true for the intestinal damage and the rise in hematocrit and arterial lactate.

The changes in oxygen transport and hemodynamics during retrograde whole-body extracorporeal perfusion (retro-ECC) were studied in six mongrel dogs. Oxygen consumption during retro-ECC, in which the blood flow rate was set at 25% and 50% of the flow during antegrade extracorporeal perfusion (ante-ECC), respectively, was relatively high compared with that during ante-ECC. These changes were caused by an increase in the oxygen extraction ratio to 71.5% +/- 8.2% and 51.2% +/- 12.4% during retro-ECC/25% and retro-ECC/50%, respectively. Thus, tissue perfusion was apparently well maintained by retrograde perfusion on the basis of the oxygen transport data. However, central venous pressure increased markedly to 29.5 +/- 11.6 mmHg and 56.2 +/- 24.5 mmHg during retro-ECC/25% and retro-ECC/50%, respectively, because of massive venous congestion caused by insufficient arterial return of perfused blood. The great venous compliance and increased systemic vascular resistance were the main causes of circulatory failure during retro-ECC. The risk of serious complications owing to the venous congestion must be considered during retrograde perfusion, especially during the clinical application of retrograde cerebral perfusion.

The aim of this study was to determine the hemodynamic effect of somatostatin, either prophylactically or therapeutically, in shock caused by acute necrohemorragic pancreatitis in conscious rats. For this purpose, radioactive microspheres were used in 3 groups (control pancreatitis, therapeutic somatostatin and prophylactic somatostatin), performing a basal and final hemodynamic study. In the control group, acute necrohemorragic pancreatitis resulted in overwhelming shock with decrease of 55% in cardiac output, 58% in renal blood flow, increase in total peripheral resistances of 342%, and death after 70 min. Therapeutic somatostatin decreased cardiac output by 42%, renal blood flow by 47%, and increased total peripheral resistances by 153%. Prophylactic somatostatin decreased cardiac output by 24%, and renal blooded flow by 28%; it increased peripheral resistances by 146%, and improved survival up to 97 min. In conclusion, therapeutic somatostatin, and particularly prophylactic somatostatin, improved hemodynamic shock after acute necrohemorragic pancreatitis in conscious rats.

Many of our patients in ICUs suffer from shock, be it due to sepsis, trauma, arrest, or other causes. These patients continue to have a very high mortality rate in spite of very labor intensive and expensive treatment. The ability to identify patients who are likely to succumb to their illness is of utmost importance. Of the multitude of scoring systems published, the APACHE seems to accurately stratify shock patients according to severity of illness. However, these systems tend to be more useful for stratifying risk groups of patients than assessing the risk of death. Hemodynamic data can specifically assess the severity of the shock state in an individual patient. Those who maintain a relatively low cardiac index (< 4.5 L/m/M2) and oxygen delivery (< 15 mL/m/kg or 600 mL/m/M2) have persistent tissue hypoperfusion. Arterial lactate concentrations reflect the severity of this perfusion defect and correlate with outcome. Therefore, by restoring tissue perfusion, we can clearly improve mortality. CPP, although not generally obtainable during cardiac arrest, is the major physiologic determinant of outcome from CPR. ETCO2 monitoring during cardiac arrest in humans correlates with resuscitability, however, provides a rapid noninvasive monitor of cardiac output, and therefore has secured its role as an invaluable tool for assessing the effectiveness of CPR. An ETCO2 over 10 mm Hg is associated with effective CPR. A rapid rise in ETCO2 during CPR heralds recovery of spontaneous circulation. In conclusion, the use of prognostic indicators as predictors of outcome is supported as an important adjunct to the management of critically ill patients. These indicators serve as useful monitors to evaluate treatment and guide clinical management. Understanding the underlying pathophysiologic mechanisms responsible for the wide variety of illnesses associated with circulatory failure is crucial in our concerted effort to reduce mortality in these patients. As knowledge is gained, we hopefully will be able to develop more accurate and specific predictors of outcome to prudently select patients most likely to benefit.

Objective: Acute adrenocortical insufficiency is an unusual cause of isolated shock. The purpose of this study is to describe the cardiovascular changes in 6 patients with acute adrenal insufficiency presenting with hemodynamic instability., Design: Retrospective and prospective study., Setting: Medical intensive care unit in a university hospital., Patients: 6 patients studied by right cardiac catheterization., Measurements and Results: Results before glucocorticoid treatment show two possible hemodynamic states: 1) myocardial depression with hypovolemia in 3 patients, and 2) hyperdynamic shock with high cardiac output and diminished systemic arterial resistance in 3 other patients. The 3 patients presenting hyperdynamic shock were all given intravenous fluid therapy of over 20 ml/kg before the first hemodynamic measurement. For 2 other patients with low cardiac index and high systemic arterial resistance studied prospectively, 20 ml/kg intravenous fluid therapy transformed the hemodynamic state to hyperdynamic shock. The cardiovascular effect of glucocorticoid treatment studied in 4 patients was resulted in an improvement in the left ventricular systolic work index., Conclusions: Diagnosis of acute adrenocortical insufficiency must be considered if clinical manifestations are present suggesting septic shock without any obvious infectious cause in patients having undergone considerable intravenous fluid therapy as an initial course of treatment.

The investigation of central haemodynamics indexes dynamics with the use of the developed automatized system in 65 patients with pancreonecrosis was conducted for the aim of disease course prognostication and differentiated prescription of cardiotonics. Three stages of circulatory disorders were established. The possibility of patient's death significantly increases in the presence of prolonged depression of cardiac output when rapid effect of conservative therapy is absent.