Sunday, May 23, 2010

Inferior vena caval (IVC) filters in Deep vein thrombosis

DVT occurring in deep knee or thigh veins, known as proximal DVT, require hospitalization and anticoagulation because of increased risk of pulmonary embolus.

Most experts agree with placing an inferior vena caval (IVC) filters in patients with acute proximal DVT and an absolute contraindication to anticoagulation. If the contraindication to anticoagulation is temporary (eg, perisurgical patients), placement of a retrievable IVC filter should be considered so that the device can be removed once anticoagulation has been started and has been shown to be tolerated. 

Complications of IVC filters include local thrombosis, tilting, migration, and inability to retrieve the device.

Child-Turcotte-Pugh and Model for End-Stage Liver Disease (MELD) scoring systems for staging cirrhosis.


 Child-Turcotte-Pugh
and Model for End-Stage Liver
Disease (MELD) scoring systems for staging cirrhosis.

Child-Turcotte-Pugh scoring system
Numerical Score
Parameter123
AscitesNoneSlightModerate to severe
EncephalopathyNoneSlight to moderateModerate to severe
Bilirubin (mg/dL)< 2.02–3> 3.0
Albumin (g/dL)> 3.52.8–3.5< 2.8
Prothrombin time (seconds increased)1–34–6> 6.0
Total numerical score and corresponding Child-Turcotte-Pugh
class
 
Score Class 
5–6A
7–9B
10–15C
MELD scoring system 
MELD = 11.2 loge (INR) + 3.78 loge (bilirubin [mg/dL]) + 9.57 loge (creatinine [mg/dL]) + 6.43 (Range 6–40).


INR, international normalized ratio.

Prognosis

  • Factors determining survival include ability to stop alcohol intake and the Child-Turcotte-Pugh class
  • The Model for End-Stage Liver Disease (MELD) is used to determine priorities for liver transplantation

Wednesday, May 19, 2010

Ranson's Criteria

Table 33-4 Ranson's
Prognostic Signs of Pancreatitis

Criteria for acute pancreatitis not due to gallstones 
At admissionDuring the initial 48 h
  Age >55 y  Hematocrit fall >10 points
  WBC >16,000/mm3
  BUN elevation >5 mg/dL
  Blood glucose >200 mg/dL  Serum calcium <8 mg/dL
  Serum LDH >350 IU/L  Arterial PO2 <60
mm Hg
  Serum AST >250 U/dL  Base deficit >4 mEq/L
     Estimated fluid sequestration >6 L
Criteria for acute gallstone pancreatitis 
At admissionDuring the initial 48 h
  Age >70 y  Hematocrit fall >10 points
  WBC >18,000/mm3
  BUN elevation >2 mg/dL
  Blood glucose >220 mg/dL  Serum calcium <8 mg/dL
  Serum LDH >400 IU/L  Base deficit >5 mEq/L
  Serum AST >250 U/dL  Estimated fluid sequestration >4 L


AST = aspartate
transaminase; BUN = blood urea nitrogen; LDH = lactate
dehydrogenase; PO2 = partial pressure
of oxygen; WBC = white blood cell count.

Source: Data from Ranson JHC: Etiological and prognostic factors
in human acute pancreatitis: A review. Am J Gastroenterol 77:633,
1982. From Macmillan Publishers Ltd. Ranson JH, Rifkind KM, Roses
DF, et al: Prognostic signs and the role of operative management
in acute pancreatitis. Surg Gynecol Obstet 139:69,
1974.

MRCP (Magnetic resonance cholangiopancreatography )

Indication
Evaluation of intra- and extra-hepatic biliary and pancreatic duct dilatation, and the cause of obstruction.

Advantages
Noninvasive. No ionizing radiation. Imaging in all planes. Can image ducts beyond the point of obstruction.
Evaluates extra-luminal disease.

Disadvantages/Contraindications
Special instrumentation required for patients on life support.

Contraindications and risks: Contraindicated in patients with cardiac pacemakers, intraocular metallic foreign bodies, intracranial aneurysm clips, cochlear implants, and some artificial heart valves.

Preparation
Preferably NPO for 6 hours.

Endoscopic retrograde cholangiopancreatography (ERCP)

Indications
Demonstrates cause, location, and extent of extrahepatic biliary obstruction (eg, choledocholithiasis).
Can diagnose chronic pancreatitis.
Primary sclerosing cholangitis, AIDS-associated cholangitis, and cholangiocarcinomas.

Advantages
Avoids surgery.
Less invasive than percutaneous transhepatic cholangiography.
Offers therapeutic potential (sphincterotomy and extraction of common bile duct stone, balloon dilatation of strictures, placement of stents).
Finds gallstones in up to 14% of patients with symptoms but negative ultrasound.

Disadvantages/Contraindications
Requires endoscopy. May cause pancreatitis (1%), cholangitis (<1%), peritonitis, hemorrhage (if sphincterotomy performed), and death (rare).

Contraindications and risks: Relatively contraindicated in patients with concurrent or recent (<6 weeks) acute pancreatitis or suspected pancreatic pseudocyst. Contraindicated in pregnancy because of the potential harm of ionizing radiation to the fetus.

Preparation
NPO for 6 hours.
Sedation required.
Vital signs should be monitored by the nursing staff.
Not possible in patient who has undergone Roux-en-Y hepaticojejunostomy.