Hemodynamics I: Edema, Congestion & Hemorrhage

Hemodynamics I: Edema, Congestion & Hemorrhage

  1. Define edema

THREE POINTS MENTIONED IN LECTURE. 1). EDEMA RESULTS WHEN THE BALANCE IS UPSET AND THERE IS AN ACCULUMATION OF EXCESS FLUID IN INTERSITIAL (INTERCELLULAR) TISSUE SPACES OR BODY CAVITIES. 2). EDEMA CAN ALSO BE DEFINED AS PROBLEMS WITH FLUID DISTRIBUTION DUE TO INCREASE IN FORCES WHICH FAVOR FILTRATION INTO AND/OR ACCULUMATION  IN TISSUES. AND, 3) EDEMA MAY BE, BUT NOT ALWAYS ASSOCIATED WITH FLUID EXCESS.

 

  1. List and understand the pathophysiologic mechanisms (or categories) of edema
  2. IMPAIRED VENOUS RETURN/INCREASED HYDROSTATIC PRESSURE
  3. REDUCED PLASMA ONCOTIC PRESSURE
  4. SODIUM AND WATER RETENTION-OFTEN OCCURS W/ #2
  5. LYMPHATIC OBSTRUCTION
  6. INFLAMMATORY EDEMA

 

  1. Compare and contrast transudate and exudates, with reference to composition and pathogenesis

TRANSUDATE- SEEN IN NON-INFLAMMATORY EDEMA WITH A PROTEIN-POOR CONTENT (X < 1.012)

 

EXUDATE-SEEN IN INFLAMMATORY EDEMA, WITH A PROTEIN-RICH FLUID CONTENT (X > 1.020)

 

  1. List important clinical settings in which edema is caused (solely or principally) by:
  2. Increased hydrostatic pressure= CHF
  3. Reduced plasma oncotic pressure= NEPHROTIC SYNDROME
  4. Lymphatic obstruction= TUMOR
  5. d.   Sodium retention= CIRRHOSIS & ACUTE RENAL FAIL

 

  1. Understand why edema occurs in acute inflammation

THIS IS A NORMAL RESPONSE/FIRST RESPONSE TO A HARMFUL AGENT. THERE ARE CHANGES IN BOTH THE VASCULAR CALIBER AND MICROVASCULATURE. THE MICROVASCULATURE BECOMES LEAKY-THIS ALLOWS PROTEINS TO LEAK OUT, AS WELL AS LEUKOCYTES. THE CALIBER ALSO BECOMES DILATED; INCREASED BLOOD FLOW AND CAPILLARY HYDROSTATIC PRESSURE. ALL THESE FACTORS LEAD TO AN INFLUX OF FLUID AND ACCULUMATION OF LEUKOCYTES AT SITE.

 

  1. Define nephrotic syndrome

THIS IS ONE OF THE SYNDROMES WHERE THE END RESULT IS A REDUCED PLASMA ONCOTIC PRESSURE. IN THIS CASE, THERE IS NOT A PROBLEM WITH PROTEIN SYNTHESIS; IN FACT, THERE IS A PROBLEM WITH THE GLOMERULAR CAPILLARY WALL BEING LEAKY. THERE IS A MAJOR LOSS OF PROTEIN WHERE THERE SHOULD NOT BE. ON THE OTHER HAND, DIFFUSE LIVER PATHOLOGY CREATES A REDUCED PLASMA ONCOTIC PRESSURE BECAUSE OF PROBLEMS WITH ALBUMIN SYNTHESIS

 

 

 

 

  1. With respect to clinical settings of edema, know whether distribution is localized, dependent or systemic

CEREBRAL EDEMA- BOTH LOCALIZED AND SYSTEMIC

PULMONARY EDEMA- LOCALIZED

INFLAMMATORY EDEMA- LOCALIZED

CHF- SYTEMIC AND MOST PROMINENT IN DEPENDENT PORTIONS

NEPHROTIC SYNDROME- SYSTEMIC

TUMOR- LOCALIZED

 

  1. Know the gross and microscopic morphologic features of pulmonary edema, and understand their pathogenesis

PATHOGENESIS- ASSOCIATED WITH L. HEART FAILURE, RENAL FAILURE AND LUNG INFECTIONS

 

GROSS- LUNGS ARE WET AND 2-3X THE NORMAL SIZE. FROTHY WITH A MIXTURE OF BLOOD AND AIR

 

MICROSCOPIC- ALVEOLI FILLED WITH HOMOGENOUS, PINK, AIR BUBBLES

-HYPOXIA TO DEATH

– RICH MEDIUM FOR BACTERIA- PNEUMONIA SUPERIMPOSED

 

  1. What is the clinical significance of pulmonary and cerebral edema?

DEATH!

 

10.Define, compare and contrast hyperemia and congestion

TERM CONGESTION HYPEREMIA
AMOUNT OF BLOOD MORE NORE
PROCESS PASSIVE/ OBSTRUCTION INCREASED BLOOD FLOW
PROBLEM IMPAIRED OUTFLOW RECRUITMENT AND DILATION
COLOR CYANOTIC RED

 

11.Compare and contrast the gross microscopic morphologic features of acute and chronic pulmonary congestion and understand their pathogenesis

FACTOR ACUTE CHRONIC
ORIGIN/CAUSE M.I. CHF
GROSS OBSERVATIONS HEAVY, WET, HEMORRHAGIC SAME WITH ALSO AN INCREASE IN FIBROTIC TISSUE WITHIN SEPTA
CAPILLARIES SWOLLEN/DISTENDED RUPTURE
HEART FAILURE CELLS N/A PRESENT

 

12.What is the most frequent cause of pulmonary congestion?

CHF

 

13.What is the significance of ‘heart failure cells’ in pulmonary congestion?

THEY ARE SUGGESTIVE OF LONG-STANDING PULMONARY CONGESTION; RBC’S ARE BREAKING DOWN AND THUS, HAVE MACROPHAGES FILLED WITH HEMOSIDERIN.

 

 

14.Know the gross and microscopic features of congestion in the liver and understand their pathogenesis

GROSS FEATURES: CONGESTED LIVER RESEMBLES A CROSS-SECTION OF A NUTMEG. THERE ARE DARK RED FOCI OF CONGESTION IN CONTRAST WITH THE PALER TAN PERIPHERAL ZONES. THIS IS TO THE INCREASED VENOUS PRESSURE, WHICH HAS DILATED SOME OF THE SINUSOIDS WITH BLOOD. THEREFORE, CAUSING A PRESSURE ATROPHY OF THE HEPATOCYTES

MICROSCOPIC FEATURES: HEPATIC FIBROSIS AND CARDIAC CIRRHOSIS. THERE HAS BEEN A DILATION OF THE BLOOD-FILLED CENTRAL VEINS. THERE HAS ALSO BEEN CENTRLOBAR NECROSIS WITH HEPATOCYTE DROP-OUT. HEMOSIDERIN AND MACROPHAGES NOTED

 

15.What is the most frequent cause of hepatic congestion?

RIGHT HEART FAILURE

 

16.What is the most frequent cause of chronic congestion of the spleen?

THE MOST FREQUENT CAUSE IS PORTAL HTN; ANATOMICAL BASIS FOR CONGESTION. BACK-UP FROM PORTAL TRIAD

 

17.Define hemorrhage

LOSS OF BLOOD FROM A VASCUALR COMPARTMENT, WHERE THE BLOOD CAN EITHER ACCULUMATE IN TISSUES OR SPACES OF THE BODY, OR 2) BE AN EXTERNAL HEMORRHAGE.

 

18.What is the basic cause of hemorrhage?

HEMORRHAGES ARE USUALLY SECONDARY TO A RUPTURED VESSEL

 

19.What determines the clinical significance of hemorrhage? (Name 3 determining factors)

  1. VOLUME OF BLOOD LOSS
  2. RATE OF BLOOD LOSS
  3. SITE OF HEMORRHAGE

 

20.Define hematoma, hemothorax, hemopericardium, hemoperitoneum, petechia, purpura and ecchymosis

HEMATOMA- ACCUMULATION OF BLOOD IN SOFT TISSUES

HEMOTHORAX- HEMORRHAGE INTO PLEURAL CAVITY

HEMOPERICARDIUM-HEMORRHAGE INTO PERICARDIAL SPACE

HEMOPERITONEUM- BLEEDING/HEMORRHAGE INTO PERITONEAL CAVITY

PETECHIA- PINPOINT HEMORRHAGES IN HE SKIN, CONJUNCTIVA, MUCOUS MEMBRANES, OR SEROSAL SURFACES

PURPURA- UP TO 1 CM; TRAUMA, LOCAL INFLAMMATION, AND FRAGILITY

ECCHYMOSIS- LARGER, SUB-Q BRUISES; ASSOCIATED WITH TRAUMA

 

21.Give examples of hemorrhage, which may lead to exsanguinations

  1. GUN SHOT WOUNDS
  2. MVA’S
  3. DISSECTING AORTIC ANEURYSM

 

Foot Patchpad

 

Posted on ตุลาคม 15, 2012, in บทความ. Bookmark the permalink. ใส่ความเห็น.

ใส่ความเห็น

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / เปลี่ยนแปลง )

Twitter picture

You are commenting using your Twitter account. Log Out / เปลี่ยนแปลง )

Facebook photo

You are commenting using your Facebook account. Log Out / เปลี่ยนแปลง )

Google+ photo

You are commenting using your Google+ account. Log Out / เปลี่ยนแปลง )

Connecting to %s

%d bloggers like this: