Physiologic Based Management of Circulatory Shock Kuwait 2018

Transcription

1 Physiologic Based Management of Circulatory Shock Kuwait 2018 Dr. Yasser Elsayed, MD, PhD Director of the Targeted Neonatal Echocardiography, Point of Care and Hemodynamics Program Staff Neonatologist and echo-cardiologist

2 Disclosure No conflict of financial interest to disclose

3 Main Objectives To demonstrate: 1. Physiologic assessment of abnormal blood pressure changes 2. Pathophysiologic patterns of circulatory shock 3. Clinical categories of circulatory shock and the physiologic based approach

4 What is the your reliable definition of low BP? a. MBP< post menstrual age b. MBP< 30 mmhg c. MBP< 25 mmhg d. Systolic or diastolic pressure < 2 SD for age e. We don t have specific definition (relying on multiple markers)

5 Evidence based management of hypotension from NRN (USA)

6 The conclusion of the study For the 15 definitions of low BP investigated: Therapy was not prescribed for up to 50% of infants with low BP (50 % of INFANTS WITH LOW BLOOD PRESSURE MAY IMPROVE WITHOUT TREATMENT) Therapy was administered for up to 41% of infants without low BP. IF YOU ARE SOLELY RELYING ON BLOOD PRESSURE: YOU MAY MISS ALMOST 50% OF CASES IN EARLY STAGES OF SHOCK OR DIAGNOSING THEM LATE WITH IRREVERSIBLE SHOCK

7 Systolic and diastolic pressures Systolic blood pressure: 1. Pressure created by ventricular contractile function to exceed vascular resistance (afterload) 2. To push SV through CVS Diastolic blood pressure: 1. Resistance by contractile property of arterioles (SVR) 2. To maintain higher pressure gradient at arterial side (proximal > distal (resistance and intravascular volume) VR Myocardial performance SV SVR Overall Vascular volume

8 PATHOPHYSIOLOGIC PATTERNS OF COMPROMISED CIRCULATION (4 PATTERNS)

9 1-Low systemic vascular resistance Peripheral vasodilation in SIRS or iatrogenic The most common mechanism Explanation Myocardial muscle is more tolerant to changes in PH and hypoxia compared to pulmonary and systemic vasculature

10 2-Low preload Definition Preload is the diastolic filling of the ventricle until reaching the physiologic end diastolic volume Expected in: Severe hypovolemia Severe pulmonary hypertension External compression by high MAP or tension pneumothorax, and HCM) (Low systolic, normal or low diastolic with narrow PP)

11 3-High Afterload Definition Afterload is contractile work load that ventricle should perform to overcome the resistance Expected in: Failure of adaptation 1. Failure of Post natal transition 2. Post PDA ligation syndrome

12 4-Poor myocardial performance Low SV Definition Impaired ventricular contractility against low, normal vascular resistance. Expected in: Advanced shock due to systemic inflammatory response cardiomyopathy and prolonged arrhythmia

13 CLINICAL CATEGORIES (3 CATEGORIES)

14 Category one: low peripheral vascular resistance: Blood pressure components are low (SBP, DBP, and MBP), with normal pulse pressure. Drop of BP > 5mmHg /h is significant

15 Delayed compliance or stress relaxation after sudden change in volume (unnecessary or over transfusion or) or after drop of volume or pressure NOT related to contractility but related viscoelastic property, mainly veins

16 2 Boluses 10 cc/kg Dopamine of 5 ug/kg/min shift to vasopressin

17 Category two: High ventricular afterload (High systemic vascular resistance with low cardiac output) Low to normal SBP with high DBP and narrow pulse pressure (PP) Pathognomonic marker is narrowing of the pulse pressure (< 10 mmhg for preterm infants < 24 hours old and<20mmhg for > 24 hours old,

18 Preterm 30 weeks, 7 days old with lactic acidosis, renal failure on Lasix infusion to keep UOP >1 ml/kg/h. On HFJV and FIO2 of 40% What is your DD?

19 After start of Milrenone

20 Category three (Low cardiac output or myocardial dysfunction with normal or low systemic vascular resistance): Blood pressure trends: Low all BP components SBP, DBP and MBP) with narrow pulse pressure (PP)

21 25 weeks day 1 with hypotension and lactic acid of 5 Epinephrine of 0.05

22 Pulse pressure vs MAP in prediction of death

23 Conclusion 1- look at the TREND of systolic, diastolic and pulse pressures before and after any deterioration and intervention 2- Compare the values to the normalized centile curves for PMA 3- Integrate the impression from systolic and diastolic pressure with other parameters (UOP, acidosis, MAP, fluid status, Hb, oxygen requirement, and peripheral perfusions) 4- Change your formulated recommendation if there is no improvement after 1-2 hours, or worsening after any time 5- Consider echocardiography by an expert person if the case is worsening despite multiple strategies

24 Thank You Questions?