• Fluid therapy
• General anesthesia
• Intraoperative monitoring
• Pulse pressure
• Retrospective study

• Humans
• Female
• Retrospective Studies
• Male
• Middle Aged
• Respiration, Artificial
• Aged
• Operating Rooms
• Fluid Therapy/methods
• Tidal Volume/physiology
• Intraoperative Care/methods
• Adult
• Switzerland
• Blood Pressure/physiology
• Positive-Pressure Respiration/methods
• Germany

• Universitätsmedizin Rostock (8980)

• Cardiac surgery
• Fluid responsiveness
• Hemodynamic monitoring
• Pulmonary artery catheter
• Swan-Ganz

• anaesthesia in cardiology
• anaesthetics
• cardiac surgery
• thoracic surgery

• Cardiac Surgical Procedures
• Fluid Therapy
• Hemodynamics
• Humans
• Reproducibility of Results
• Stroke Volume
• Thoracic Surgery

The prediction accuracy of pulse pressure variation (PPV) for fluid responsiveness was suggested to be unreliable in low tidal volume (VT) ventilation. However, high PEEP can cause ARDS patients relatively hypovolemic and more fluid responsive. We hypothesized that high PEEP 15 cmH₂O can offset the disadvantage of low VT and improve the predictive performance of PPV. We prospectively enrolled 27 hypovolemic ARDS patients ventilated with low VT 6 ml/kg and three levels of PEEP (5, 10, 15 cmH₂O) randomly. Each stage lasted for at least 5 min to allow for equilibration of hemodynamics and pulmonary mechanics. Then, fluid expansion was given with 500 ml hydroxyethyl starch (Voluven 130/70). The hemodynamics and PPV were automatically measured with a PiCCO2 monitor. The PPV values were significantly higher during PEEP15 than those during PEEP5 and PEEP10. PPV during PEEP15 precisely predicts fluid responsiveness with a cutoff value 8.8% and AUC (area under the ROC curve) of ROC (receiver operating characteristic curve) 0.847, higher than the AUC during PEEP5 (0.81) and PEEP10 (0.668). Normalizing PPV with driving pressure (PPV/Driving-P) increased the AUC of PPV to 0.875 during PEEP15. In conclusions, high PEEP 15 cmH₂O can counteract the drawback of low VT and preserve the predicting accuracy of PPV in ARDS patients.

• Esophageal Doppler
• fluid responsiveness
• one-lung ventilation
• positive end-expiratory pressure
• pulse pressure variation
• stroke volume variation

Heart-lung interaction mechanisms are generally not well understood. Mechanical ventilation, for example, accentuates such interactions and could compromise cardiac activity. Thereby, assessment of ventilation-induced changes in cardiac function is considered an unmet clinical need. We believe that mathematical models of the human cardiopulmonary system can provide invaluable insights into such cardiorespiratory interactions. In this article, we aim to use a mathematical model to explain heart-lung interaction phenomena and provide physiologic hypotheses to certain contradictory experimental observations during mechanical ventilation. To accomplish this task, we highlight three model components that play a crucial role in heart-lung interactions: 1) pericardial membrane, 2) interventricular septum, and 3) pulmonary circulation that enables pulmonary capillary compression due to lung inflation. Evaluation of the model’s response under simulated ventilation scenarios shows good agreement with experimental data from the literature. A sensitivity analysis is also presented to evaluate the relative impact of the model’s highlighted components on the cyclic ventilation-induced changes in cardiac function.

Aim: Cardiac pressure-volume (PV loop) analysis under β-adrenergic stimulation is a powerful method to simultaneously determine intrinsic cardiac function and β-adrenergic reserve in mouse models. Despite its wide use, several key approaches of this method, which can affect murine cardiac function tremendously, have not been experimentally investigated until now. In this study, we investigate the impact of three lines of action during the complex procedure of PV loop analysis: (i) the ventilation with positive end-expiratory pressure, (ii) the time point of injecting hypertonic saline to estimate parallel-conductance, and (iii) the implications of end-systolic pressure-spikes that may arise under β-adrenergic stimulation.

Methods and Results: We performed pressure-volume analysis during β-adrenergic stimulation in an open-chest protocol under Isoflurane/Buprenorphine anesthesia. Our analysis showed that (i) ventilation with 2 cmH₂O positive end-expiratory pressure prevented exacerbation of peak inspiratory pressures subsequently protecting mice from macroscopic pulmonary bleedings. (ii) Estimations of parallel-conductance by injecting hypertonic saline prior to pressure-volume recordings induced dilated chamber dimensions as depicted by elevation of end-systolic volume (+113%), end-diastolic volume (+40%), and end-diastolic pressure (+46%). Further, using this experimental approach, the preload-independent contractility (PRSW) was significantly impaired under basal conditions (−17%) and under catecholaminergic stimulation (−14% at 8.25 ng/min Isoprenaline), the β-adrenergic reserve was alleviated, and the incidence of ectopic beats was increased >5-fold. (iii) End-systolic pressure-spikes were observed in 26% of pressure-volume recordings under stimulation with 2.475 and 8.25 ng/min Isoprenaline, which affected the analysis of maximum pressure (+11.5%), end-diastolic volume (−8%), stroke volume (−10%), and cardiac output (−11%).

Conclusions: Our results (i) demonstrate the advantages of positive end-expiratory pressure ventilation in open-chest instrumented mice, (ii) underline the perils of injecting hypertonic saline prior to pressure-volume recordings to calibrate for parallel-conductance and (iii) emphasize the necessity to be aware of the consequences of end-systolic pressure-spikes during β-adrenergic stimulation.

• catheter entrapment
• end-systolic pressure-spikes
• hemodynamics
• hypertonic saline
• parallel-conductance
• positive end-expiratory pressure
• pressure-volume analysis
• β-adrenergic stimulation

In last few years, emphasis was placed in goal-directed therapy in order to optimize patient's hemodynamic status and improve their prognosis. Parameters based on the interaction between heart and lungs have been questioned in situations like low tidal volume and open chest surgery. The goal of the study was to analyze the changes that one-lung ventilation can produce over stroke volume variation and to assess the possible impact of airway pressures and lung compliance over stroke volume variation.

Prospective observational study, 112 patients undergoing lung resection surgery with one-lung ventilation periods were included. Intravenous fluid therapy with crystalloids was set at 2 mL.g⁻¹. Hypotension episodes were treated with vasoconstrictive drugs. Two-lung Ventilation was implemented with a TV of 8 mL.g⁻¹ and one-lung ventilation was managed with a TV of 6 mL.g⁻¹. Invasive blood pressure was monitored. We recorded the following cardiorespiratory values: heart rate, mean arterial pressure, cardiac index, stroke volume index, airway peak pressure, airway plateau pressure and static lung compliance at 3 different times during surgery: immediately after lung collapse, 30 min after initiating one-lung ventilation and after restoration of two-lung ventilation.

Stroke volume variation values were influenced by lung collapse (before lung collapse 14.6 (DS) vs. OLV 9.9% (DS), p < 0.0001); or after restoring two-lung ventilation (11.01 (DS), p < 0.0001). During two-lung Ventilation there was a significant correlation between airway pressures and stroke volume variation, however this correlation lacks during one-lung ventilation.

The decrease of stroke volume variation values during one-lung ventilation with protective ventilatory strategies advices not to use the same threshold values to determine fluid responsiveness.

• afterload
• neonatal rat model
• pulmonary artery banding
• right ventricular

• Anesthesiology
• Oesophageal Neoplasms
• Oesophagectomy
• Perioperative Risk
• Surgery

• cardiac surgery
• dog
• electrical velocimetry
• fluid therapy
• haemodynamic monitoring

The importance of the safety of healthy living liver donors is widely recognized during donor hepatectomy which is associated with blood loss, transfusion, and subsequent post-operative morbidity. Although the low central venous pressure (CVP) technique can still be effective, it may not be advantageous concerning the safety of healthy donors undergoing hepatectomy. Emerging evidence suggests that stroke volume variation (SVV), a simple and useful index for fluid responsiveness and preload status in various clinical situations, can be applied as a guide for fluid management to reduce blood loss during living donor hepatectomy. Synthetic colloid solutions are also associated with serious adverse events such as the use of renal replacement therapy and transfusion in critically ill or septic patients. However, it is uncertain whether the intra-operative use of colloid solution is associated with similarly adverse effects in patients undergoing living donor hepatectomy. In this review article we discuss the recent issues regarding the low CVP technique and the high SVV method, i.e., maintaining 10%-20% of SVV, for fluid management in order to reduce blood loss during living donor hepatectomy. In addition, we briefly discuss the effects of intra-operative colloid or crystalloid administration for surgical rather than septic or critically ill patients.

• Donor hepatectomy
• Central venous pressure
• Stroke volume variation
• Fluid
• Synthetic colloid

• Blood Loss, Surgical/prevention & control
• Crystalloid Solutions
• Fluid Therapy/adverse effects
• Fluid Therapy/methods
• Humans
• Isotonic Solutions/administration & dosage
• Isotonic Solutions/adverse effects
• Liver Transplantation/adverse effects
• Liver Transplantation/methods
• Living Donors
• Monitoring, Intraoperative/methods
• Predictive Value of Tests
• Stroke Volume
• Treatment Outcome

• heart failure with preserved ejection fraction
• myocardial stiffness
• spectral analysis
• spectral transfer function

• cardiac output
• positive end-expiratory pressure
• pulmonary artery catheter
• right ventricle
• stroke volume variation
• thermodilution

• Aged
• Artifacts
• Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography/instrumentation
• Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography/methods
• Female
• Humans
• Image Interpretation, Computer-Assisted/methods
• Male
• Organophosphorus Compounds
• Organotechnetium Compounds
• Patient Positioning/methods
• Prone Position
• Radiopharmaceuticals
• Reproducibility of Results
• Semiconductors
• Sensitivity and Specificity
• Stroke Volume
• Supine Position
• Ventricular Dysfunction, Left/diagnostic imaging

• Acute Disease
• Child
• Child, Preschool
• Critical Illness
• Extravascular Lung Water
• Female
• Humans
• Infant
• Male
• Prognosis
• Respiratory Insufficiency/mortality
• Respiratory Insufficiency/physiopathology
• Survival Rate

• Aged
• Algorithms
• Blood Volume
• Coronary Artery Bypass, Off-Pump
• Female
• Fluid Therapy
• Hemodynamics
• Humans
• Male
• Middle Aged
• Monitoring, Physiologic
• Oxygen/blood
• Thermodilution

• Anesthesia
• Animals
• Female
• Hemodynamics/drug effects
• Swine
• Ventricular Function, Right/drug effects
• Xenon/pharmacology

Adequate fluid loading is the first step of hemodynamic optimization in cardiac patients undergoing surgery. Neither a clinical approach alone nor conventional parameters like central venous pressure (CVP) and pulmonary capillary wedge pressure (PCWP) are thought to be sufficient for recognizing fluid deficiency or overload. The aim of this study was to evaluate the suitability of CVP, PCWP, global end-diastolic volume index (GEDVI), pulse pressure variation (PPV), and stroke volume variation (SVV) for predicting changes in the cardiac index (CI) and stroke volume index (SVI) after sternotomy.

In 40 patients, CVP, PCWP, GEDVI, PPV, SVV, and the CI were measured at two points of time. One measurement was performed after inducing anesthesia and one after sternotomy.

A significant increase in heart rate, CI, and GEDVI was observed during the study period. CVP, SVV, and PPV decreased significantly. There were no significant correlations between CVP and PCWP and changes in CI. In contrast, GEDVI, SVV, and PPV significantly correlated with CI changes. Only relative changes of GEDVI, SVV, and PPV predicted changes in SVI.

During cardiac surgery and especially after sternotomy, CVP and PCWP are not suitable for monitoring fluid status. Direct volume measurement like GEDVI and dynamic volume responsive measurements like SVV and PPV may be more suitable for monitoring the volume status of patients, particularly under open-chest conditions.

• Blood Pressure
• Heart/physiology
• Humans
• Lung/physiology
• Monitoring, Physiologic
• Positive-Pressure Respiration/methods
• Pulse
• Stroke Volume

• HL073198 NHLBI NIH HHS
• HL07820 NHLBI NIH HHS
• HL67181 NHLBI NIH HHS

• Animals
• Anti-Arrhythmia Agents/pharmacology
• Blood Pressure/drug effects
• Blood Pressure/physiology
• Coronary Circulation/drug effects
• Coronary Circulation/physiology
• Coronary Vessels/physiology
• Femoral Nerve/surgery
• Glyburide/pharmacology
• Hindlimb
• Ischemic Preconditioning/methods
• Male
• Models, Animal
• Swine
• Vascular Resistance/drug effects
• Vascular Resistance/physiology
• Ventricular Function, Left/physiology