Hypo- and Hypervolemic Status Assessment in Pediatric and Neonatal Patients

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1 Hypo- and Hypervolemic Status Assessment in Pediatric and Neonatal Patients TEDVI -Heart at end of diastole CBVI -Heart -Lungs -Large Central Vessels ACVI -Heart -Lungs -Brain, Liver, Kidneys, etc. *ACVI is close to total blood volume in infants COstatusParameters(CO-29-fly)RevB2016USltr

2 Blood Volume Measurement Calculations Total End Diastolic Volume Index (TEDVI) TEDVI = CO x (1.62/HR x CHc) / BW Total End Diastolic Volume is the amount of blood volume in the four chambers of the heart at the end of diastole. Calculation of TEDV assumes that the spread of the arterial indicator dilution curve from its initial venous shape results largely from indicator mixing in the heart chambers. This measurement is not valid for patients with shunts. Curve Spread Central Blood Volume Index (CBVI) CBVI = CO x (MTTa - MTTv - MTTt) / BW Mean transit time of indicator travel Central Blood Volume is calculated as the volume between the injection site (central vein) and the recording site (artery), and includes the volume of blood in the heart, lungs, and large vessels. The longer the indicator travels (large mean transit time MTTa), the larger volume is the volume between the two sites. This measurement is valid in most patient anatomies except Bidirectional Glenn. Active Circulation Volume Index (ACVI) ACVI = (Vinj/H) / BW Active Circulation Volume is the amount of blood volume that immediately supports CO through quick multiple recirculations through the heart, lungs and other low resistance organs such as the brain, liver, kidneys, etc. It is calculated as the volume of blood in which the indicator mixes in the first minute after injection. This volume is close to the total blood volume in infants. Indicator dilution in intravascular space Where: CHc = (CHart 2 - CHven 2 ) 1/2 CHven, CHart - Chord of venous and arterial indicator curves [min] HR - Heart rate [beats per minute] BW - patient s body weight [kg] MTTa - time of indicator traveling from the injection site (venous senor) to the arterial sensor MTTv - mean transit time of venous injection recorded by the venous sensor MTTt - mean transit time that indicator travels in the arterial loop before reaching the sensor H - level of isotonic saline concentration in blood [ml (saline)/ ml (blood)] at the end of the first minute after injection Vinj - volume of injected isotonic saline [ml] COstatusBloodVolumeCurve(CO-6)RevB2016USltr

3 Vital Signs Do Not Show Signs of Deep Hypovolemia 3 kg patient had low blood volumes, but good vitals (CVP, ABP, HR, SaO 2, & NIRS). The doctor pushed on the child s liver then felt fluid movement and noticed a change in vitals. Patient was hypovolemic. Vital signs showed no sign of deep hypovolemic status. Initial Two Hours Later Next Day Increased Cardiac Output and Blood Volumes to an acceptable level Initial Volumes Courtesy: Dr. Perdreau, Dr. Ros, & Dr. Mauriat, CHU Hopitaux de Bordeaux, France COstatusHypovolemia(CO-206-cs)RevB2016USltr

4 Uncontrolled Fluid Infusion Leads to Hypervolemic Status of the Patient 6 kg patient after Tetralogy of Fallot Surgery (no residual shunts). Patient becomes hypervolemic. 2 hours after surgery CVP = 18 mmhg 5 hours after surgery CVP = 9 mmhg 22 hours after surgery CVP = 12 mmhg Initial Final Courtesy: Dr. Ackermann, German Heart Centre Munich, Germany COstatusFluidOverload(CO-207-cs)RevB2016USltr

5 Fluid Overloading Increases Morbidity 1. Hassinger, A. B., Wald, E. L., & Goodman, D. M. (2014). Early Postoperative Fluid Overload Precedes Acute Kidney Injury and Is Associated With Higher Morbidity in Pediatric Cardiac Surgery Patients. Pediatr Crit Care Med, 15(2), Seguin, J., et al. (2014). Extent, Risk Factors, and Outcome of Fluid Overload After Pediatric Heart Surgery. Crit Care Med, 42(12), Hazle, M et al. (2013). Fluid overload in infants following congenital heart surgery. Pediatr Crit Care Med, 14(1), Arikan AA, Zappitelli M, Goldstein SL, Naipaul A, Jefferson LS, Loftis LL. (2012). Fluid overload is associated with impaired oxygenation and morbidity in critically ill children. PCCM 13(3), Lex DJ, Toth R, Czobor NR, et al. (2016). Fluid Overload is Associated With Higher Mortality and Morbidity in Pediatric Patients Undergoing Cardic Surgery. Pediatr Crit Care Med, 17(4), Data from [1] Data from [2] Fluid Overloading had a significant effect on how long patients were on drugs, stayed in the hospital, and were ventilated. COstatusFluidOverloadMorbidity(CO-205-cs)RevC2016USltr