The Use of New Ultrasound Indices to Evaluate Volume Status and Fluid Responsiveness in Septic Shock Patients Thesis Submitted for partial fulfillment of MD degree in Anesthesiology, Surgical Intensive Care and Pain Management By Ahmed Mohamed Lotfy Mostafa MBBCh, MSc anesthesia and Surgical Intensive Care and Pain Management Faculty of Medicine, Cairo University Under supervision of Prof. Dr. Iman Riad Mohamed Abdel Aal Professor of Anesthesia and Surgical Intensive Care Faculty of medicine, Cairo University Prof. Dr. Jihan Aly El Kholy Professor of Anesthesia and Surgical Intensive Care Faculty of medicine, Cairo University Dr. Ahmed Mohamed Ibrahim Hasanain Lecturer of Anesthesia and Surgical Intensive Care Faculty of medicine, Cairo University Faculty of Medicine Cairo University 2014
Acknowledgments ACKNOWLEDGMENTS First and foremost thanks to "ALLAH" for his help to fulfill this work. I would like to express my deepest gratitude to Professor DR. Iman Riad, professor of anesthesiology, faculty of medicine, Cairo University for her kind guidance and supervision. My thanks to Dr. Jihan Alkholy, Prof. of Anesthesiology, faculty of medicine Cairo University for her continuous encouragement & supervision. Last But not least, I am also expressing my warmest thanks to Dr. Ahmed Hasanin, Lecturer of Anesthesiology, faculty of medicine Cairo University for his generosity & positive attitude. i
Abstract This study was conducted in surgical ICU in Cairo University Hospitals to detect the accuracy of new ultrasound indices (IVC caval index, IJV/CCA cross sectional area and IJV aspect ratio) to guide fluid therapy and predict fluid responsiveness (assessed by trans-thoracic echocardiography) in severe sepsis and septic shock spontaneously breathing patients in comparison to traditional CVP measurement. The results of this study showed that the minimum IVC diameter, caval index, IJV area and the ratio IJV/CCA are good predictors of fluid responsiveness. These parameters were significantly different between the two groups of fluid responders and non-responders. A minimum IVC diameter of 0.9 cm predicted fluid responsiveness with a sensitivity of 100% and specificity of 70%. A caval index of 35% had 92% sensitivity and 86% specificity. An IJV area of 0.9 cm 2 and IJV/CCA ratio of 1.7 had a sensitivity of 85% in predicting fluid responders and a specificity of 70% and 62% respectively. Keyword CVP-IJV-CCA- AUROC- PAoP-IVC
Index Index: Introduction and aim of work. 1 Review... 3 Chapter I : Sepsis... 4 Management of Severe Sepsis........ 7 - Fluid Therapy (Early Goal Directed Therapy).... 7 - Infection Management..... 12 - Source Control..... 13 Chapter II : Ultrasound in ICU... 16 Physics of Ultrasound... 16 - Imaging Modalities... 18 Uses of Ultrasound in ICU....... 19 - Cardiac Applications.. 19 - Thoracic Applications.... 20 - Abdominal Applications... 22 Chapter III : Fluid Responsiveness... 24 Physiology..... 25 Hemodynamic Measurements of Volume Status and Fluid responsiveness..... 31 - Static Measurements 31 - Dynamic Measurements.. 34 1. Stroke Volume Variation And Pulse Pressure Variations... 34 2. Echocardiography. 37 3. Inferior Vena Cava and Superior Vena Cava Diameter...42 4. Passive Leg Raising Test 46 ii
Index - Other Methods of Assessing Fluid Responsiveness...49 Patients and methods.. 51 Ultrasound Measurement Details... 53 Statistical Analysis. 55 Results. 56 Demographic Data and Other Patient Characteristics 56 Hemodynamic Data 58 Achievement of Early Goal Directed Therapy in Fluid Responders and Non Responders.. 59 Ultrasound Indices. 61 Sensitivity and specificity of all parameters in prediction of fluid responsiveness.... 63 Correlation between baseline ultrasound indices and CVP.. 73 1. Correlation between IVC minimum diameter and CVP... 73 2. Correlation between IJV area and CVP 74 3. Correlation between caval index and CVP 75 Correlation between changes in caval index and change in VTI 76 Correlation between changes in IJV area and change in VTI. 77 Discussion.. 78 References. 89 Summery. 107 Arabic Summery. 109 iii
Abbreviations Abbreviations: APACHE.. Acute physiology and chronic health evaluation score aptt..... Activated partial thromboplastin time AUC. Area under the curve AUROC... Area under the receiver operating characteristic curve CCA. Common Carotid artery CI. Confidence interval CVP. Central venous pressure DBP. Diastolic blood pressure DIVC Variation in inferior vena cava ED Emergency department EGDT... Early goal-directed therapy F Frequency FAST Focused assessment with sonography for trauma FiO 2... Fraction of inspired oxygen HR. Heart rate Hz.. Hertz IAP. Intra-abdominal pressure ICU. Intensive care unit IJV.. Internal Jugular vein INR. International normalized ratio IVC. Inferior vena cava IVCd Inferior vena cava diameter IVC Dmax... Maximum inferior vena cava diameter IVC Dmin... Minimum inferior vena cava diameter LOS.. Length of ICU stay LV Left ventricle LVEDA Left ventricular end diastolic area iv
Abbreviations MAP. Mean arterial pressure MBP. Mean blood pressure MHz. Mega Hertz MSFP... Mean systemic filling pressure PA Pulmonary artery PaO 2. Arterial partial pressure of oxygen PAoP Pulmonary artery occlusion pressure Pcrit.. Critical pressure PCwP... Pulmonary capillary wedge pressure PEEP. Positive end expiratory pressure PLR.. Passive leg raising PPV.. Pulse pressure variation RAP. Right atrial pressure RCTs Randomized controlled trials ROC. Receiver operating characteristic Rv. Resistance to venous flow RV Right ventricle SBP.. Systolic blood pressure ScvO 2... Superior vena cava oxygen saturation SD Standard deviations SICU... Surgical intensive care unit SSC.. Surviving sepsis campaign SV Stroke volume SVC. Superior vena cava SVmax. Maximum stroke volume SVmin.. Minimum stroke volume SvO 2.. Mixed venous oxygen saturation SVV.. Stroke volume variation TEE Trans-oesophageal echocardiography v
Abbreviations TTE. Trans-thoracic echocardiography U/S.. Ultrasound VTI.. Velocity Time Index WBC White blood cell vi
Tables LIST OF TABLES Table no. Title Page no. Table 1 Diagnostic criteria of sepsis. 4 Table 2 Diagnostic criteria for severe sepsis. 6 Table 3 Grading of evidence. 15 Table 4 Grading of recommendations. 15 Table 5 Demographic data and other patient characteristics. 57 Table 6 Baseline hemodynamic data. 58 Table 7 Hemodynamic data after fluid bolus. 59 Table 8 Acheivement of targets of early goal directed therapy in the two groups. 60 Table 9 Baseline ultrasound indices. 62 Table 10 Ultrasound indices after fluid bolus. 63 Table 11 Table 12 Table 13 Area under the Receiver operating characteristic (ROC) curve for each variable as a predictor of fluid responsiveness. Sensitivity and specificity of each parameter to predict fluid responsiveness at the best cut-off values. Sensitivity and specificity of DIVC in predicting fluid responsiveness. 71 71 84 vii
Figures LIST OF FIGURES Figure no. Title Page no. Fig. 1 : The cardiac function curve representing the relationship between right atrial pressure (RAP) and cardiac output. 26 Fig. 2 : The venous return curve representing the relationship between right atrial pressure (RAP) and venous return. 28 Fig. 3 : Venous return curves is superimposed on cardiac function curves where the cardiac output and right atrial pressure (RAP) are determined at the junction of the curves assuming a theoretical steady state. 30 Fig. 4 : The physiological explanation for the changes in stroke volume and IVC diameter caused by mechanical ventilation. 41 Fig. 5 : Left ventricular end-diastolic area by TEE. 42 Fig. 6 : Distended IVC in 2D mode by TTE. Don t give volume. 45 Fig. 7 : Collapsed IVC in 2D mode by TTE. Give fluids. 46 Fig. 8 : Receiver operating characteristic (ROC) curve for central venous pressure on prediction of fluid responsiveness in septic shock patients. 64 viii
Fig. 9 : Receiver operating characteristic (ROC) curve for maximum inferior vena cava diameter (IVC) diameter on prediction of fluid responsiveness in septic shock patients. Figures 65 Fig. 10 : Receiver operating characteristic (ROC) curve for minimum internal jugular vein (IVC) diameter on prediction of fluid responsiveness in septic shock patients. 66 Fig. 11 : Receiver operating characteristic (ROC) curve for Caval index on prediction of fluid responsiveness in septic shock patients. 67 Fig. 12 : Receiver operating characteristic (ROC) curve for internal jugular vein (IJV) area on prediction of fluid responsiveness in septic shock patients. 68 Fig. 13 : Receiver operating characteristic (ROC) curve for internal jugular vein/common carotid artery (IJV/CCA) ratio on prediction of fluid responsiveness in septic shock patients. 69 Fig. 14 : Receiver operating characteristic (ROC) curve for internal jugular vein (IJV) aspect ratio on prediction of fluid responsiveness in septic shock patients. 70 Fig. 15 : Area under the receiver operating characteristic (ROC) curve for each variable on prediction of fluid responsiveness. 72 ix
Fig. 16 : Correlation between inferior vena cava (IVC) minimum diameter and central venous pressure (CVP) (r = 0.22). Figures 73 Fig. 17 : Correlation between internal jugular vein (IJV) area and central venous pressure (CVP) (r = 0.41). 74 Fig. 18 : Correlation between caval index and central venous pressure (CVP) (r = -0.23). 75 Fig. 19 : Correlation between change of caval index and change of velocity time index (VTI) (r = 0.15). 76 Fig. 20 : Correlation between change of internal jugular vein (IJV) area and change of velocity time index (VTI) (r = 0.14). 77 x
Introduction Introduction Fluid therapy is the corner stone of management of severe sepsis and septic shock and adequate fluid resuscitation is recommended worldwide to improve prognosis. However, assessment of volume status and hence fluid responsiveness can sometimes be challenging to the critical care physician. Invasive hemodynamic monitoring of central venous pressure (CVP) is still considered in directing early resuscitative efforts. Unfortunately, there are limitations of the use of CVP. First, central filling pressures are not systematically available in the initial phase of shock because a central venous catheter is not always available. Second, it has been clearly shown that static indices as CVP do not accurately predict fluid responsiveness, except for values < 5 mmhg. Therefore, fluid challenge is often used to test fluid responsiveness. Nevertheless, about 50% of fluid challenges are not justified. This exposes patients to deleterious fluid overload. Ultrasound examination has recently been used to provide information regarding responsiveness to fluids. Many studies introduced ultrasound examination as a new substitute to the traditional invasive methods, especially static dimensions. 1
Introduction Inferior vena cava (IVC) collapsibility (greater than 50%) during normal respiration was proved to be strongly associated with low central venous pressure (less than 8 mmhg). Respiratory variation in the IVC diameter was used as a guide for fluid therapy in septic shock in both spontaneous breathing and mechanically ventilated patients. Aim of the work: The aim of this work was to detect the accuracy of new ultrasound indices [IVC collapsibility index, internal jugular vein (IJV)/common carotid artery(cca) cross sectional area and IJV aspect ratio] in predicting fluid responsiveness (assessed by transthoracic echocardiography) in severe sepsis and septic shock spontaneously breathing patients in comparison to traditional CVP measurement. 2
REVIEW Chapter I: Sepsis SEPSIS Sepsis is a systemic, deleterious host response to infection. It is defined as systemic inflammatory response to infection. Severe sepsis (acute organ dysfunction secondary to documented or suspected infection) and septic shock (severe sepsis plus hypotension not reversed with fluid resuscitation) are common squeals of sepsis. Severe sepsis and septic shock are major healthcare problems, affecting millions of people around the world each year, killing one in four (and often more), and are increasing in incidence. 1 Sepsis induced hypotension is defined as a systolic blood pressure (SBP) < 90 mm Hg or mean arterial pressure (MAP) < 70 mm Hg or a SBP decrease > 40 mm Hg or less than two standard deviations (SD) below normal for age in the absence of other causes of hypotension. Septic shock is defined as sepsis-induced hypotension persisting despite adequate fluid resuscitation. Sepsis-induced tissue hypo perfusion is defined as infectioninduced hypotension, elevated lactate, or oliguria. 1 The diagnostic criteria of sepsis and severe sepsis are shown in tables 1 and 2. 3