critical care management. history 1950 iron lungs (polio and brain stem paralysis) 1958 peter safar...

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

Z m ien ion e s tan y czyn n ośc iow e m . se rcow eg o

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.