critical care management. history 1950 iron lungs (polio and brain stem paralysis) 1958 peter safar...
TRANSCRIPT
Critical Care Management
History
• 1950 iron lungs (polio and brain stem
paralysis)
• 1958 Peter Safar the first Intensive Care
Unit at Baltimore City Hospital
• 1970 Swan Ganz
Important facts in development
• Wars
• Iron lungs
• Dialysis
• Defibrillators
• Transplantation
Cost - benefit ratio?
• Acute Physiology and Chronic Health Evaluation (APACHE)
• Therapeutic Intervention Scoring System (TISS)
• Survival is inversely related to the severity of illness and number of organ systems affected
Ethical and Legal Issues
• What is justified?
• Reversability versus futility
• Decision must involve patients (or guardian), family, hospital policies and law
• Withholding versus withdrawing
• DNAR orders
Critically ill patient
• Unstable conditions in whom small changes in organ function may lead to a serious deterioration in overall body function with irrevesible organ damage and death.
• Monitoring: early to provide optimal treatment and restore a more stable physiologic condition to prevent damage and death
Respiratory therapy
• Integral part of the critical care medicine• Oxygen therapy• Causes of hypoxia• Possitive pressure ventilation: CMV, AC,
IMV, SIMV, PSV, PCV, MMV, IRV, HFJV, weaning from mechanical ventilation,
• Endotracheal intubation, sedation, paralysis,
Anesthesia for cardiovascular surgery
• Cardiopulmonary bypass
• Hypothermia and myocardial preservation
• Anesthetic management: induction, monitoring, prebypass period, cannulation, bypass time, weaning from bypass, postbypass period
• Vascular surgery
Basic parameters
• CO• V02• Preload• Afterload• Contractility• “Lucidotropic effect”• Frank-Starling
Case 1
• 55 y old man after circulatory arrest on the street – resuscitated but uncouscious.
• How to transport, where to transport, treatment?
Case 2
• 60 y old woman with a long history of asthma.
• Came to GP with respiratory distress (tachypnoe and cyanosis):
• Diagnosis?• Monitoring?• Treatment?• Where to go?
Case 3
• 40 y old man injured in car accident: can not breath, pain in the chest, conscious, RR 100/70, HR 120/min,
• Diagnosis, treatment, where to go?
Pressure-volume relationship
Regulatory mechanisms in biology
• No complex research
• No proofs
• Lot of speculations
• Molecular biology
History
• 1628 Harvey (passive)
• 1748 Radermacher (active)
• 1919 Krogh (heterogenic)
• - tissue
• - capillary
• - chaos or homestais?
Altered myocardial states
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Z aw a łB rak fu n kc ji
S tu n n in gC zasow y b rak fu n kc ji
H ib ern a tionO d w raca ln y b rak fu n kc ji
N ied ok rw ien ie /R ep erfu z ja
Sequence of events
Frank-Starling
Shock states
• Cardiovascular management
• Understand mechanisms and definition of shock states
• Signs of circulatory failure• General principles of management• Pharmacology and volume
treatment
Schematic representation of the circulatory system
Basic functions of the circulatory system
• Total (heart, veins, arteries)
• Heart (muscle, valves)
• Altered myocardial states
Definition of the circulatory insufficiency
Complex picture: left ventricular and
neurohormonal dysfunction with signs of
limited exercise capacity, fluid retention
and increse mortality rate
Signs of circulatory insufficiency
• Changes in filling pressure
• Systolic and/or diastolic dysfunction
• Emptying disturbances
Compensation mechanisms
• Increase vascular volume
• Increase filling pressures
• Tachykardia
• Hypertrophia
Myocardial stunning
Classification
• Hypovolemic
• Obstructive
• Cardiogenic
• Distributive
• Endocrine
Clinical signs
• HR
• BP
• Temperature
• Urine output
• Pulse oximetry
Invasive monitoring
• Swan-Ganz
• Pressure (PAP-PCWP)
• Volume (CO)
• Oxygenation (SvO2)
Definition of the ejection fraction
Calculations
• EDV=150 ml
• ESV=50 ml
• EF= 150-50/150 = 0.66 = 60-70%
Inotropic state
• Ino = fibre, tropos = movement
• Increase contractility = increase the power of contraction (under preload, afterload and HR)
• MV02
• Interaction between calcium and troponins
Preload
• Load just before contraction
• Venous return
• Increase LV
• Increase power of contraction
• Increase of the HR
• Example: exercices or i.v. infusion
• Relation to venous return
Afterload
• Systolic pressure
• Ventricular tension
• Periferal resistance
Relaxation failure
• 30-40% pts
• Definition: failure of filling
• Examples:
• pericarditis
• degeneration
• ischemia
• stiffness
Treatment principles
• Preload
• Contractility
• Afterload
• Oxygen delivery
Potential errors in preload estimation
• CVP (EF)
• LVEDV (compliance)
• LVEDP (MS,MI)
• LAP (elevated pulmonary pressure)
• PAOP (catheter position)
Drugs for treatment of circulatory failure
• Vasodilators
• Diuretics
• Glycosides
• Fosfodiesteraze inhibitors
• Calcium synthetizers
• Agonist beta and DM
• Antagonists beta
Vasodilators
• ACE Inhibitors: captopril, enalapril
• Nitrovasodilatators: NTG, NPS, molsidomina, hydralazyna
• Calcium channel blockers
• Potassium channel activators: diazoxide, minoxidil, pinacidil, cromakalin
Nitrate sides of action
Inotropic drugs
Fosfodiesteraze inhibitors
• Amrinone (1,5 - 2,5 mg/ kg)
• Milrinone (10 x more powerful)
• increse of cAMP, calcium concentration
and sensitivity, blood vessels dilatation
• Main indication: diastolic dysfunction of
the heart
Calcium sensitizers
• Pinobendan, Simendan, Levosimendan
• Saving energy (ATP)
• No influence on calcium homeostasis
• Drug of choice in “myocardial stunning”
• Contraindication: diastolic dysfunction
Coronary flow
• CPP DP - LVEDP
• CBF = =
• CVR CVR
Case 1
• 70 years old man 1 hour after car accident: conscious, HR 130/min, ABP 80/60 mmHg, CVP 1 mmHg, no diuresis.
Case 2
• 25 years old woman after penicillin administration: collapse, ABP 70/40, HR 70/min, CVP 2 mmHg, rush on the skin.
Case 3
• 56 years old man 3 days after MI, dyspnea, ABP 80/70, HR 110/min, CVP 10 mmHg, PCWP 25 mmHg, oliguria.