Thursday November 19, 2009

Q: Serum alkalinization with intravenous sodium bicarbonate has been the mainstay of therapy in (CA) cyclic antidepressants (amitriptyline, desipramine, imipramine, nortriptyline, doxepin, clomipramine, and protriptyline) overdose. What is the cutoff limit of QRS complex for use of intravenous sodium bicarbonate therapy?

Answer: A QRS of 100 milliseconds or greater is generally use as the cut off for intravenous sodium bicarbonate. Beside alkalinization, sodium loading may be the most important factor in the reversal of the symptoms of cyclic antidepressant toxicity. IV normal saline are indicated for CA-induced hypotension.

Wednesday November 18, 2009


Q: Which patient is more hypoxemic?

Patient A: PaO2 85 mm Hg, SaO2 95%, Hb 7 gm%
Patient B: PaO2 55 mm Hg, SaO2 85%, Hb 15 gm%


Answer:

Calculate arterial oxygen content (CaO2) (SaO2 x Hb x 1.34) assuming PaO2 is constant

Patient A
CaO2 = .95 x 7 x 1.34 = 8.9 ml O2/dl

Patient B
CaO2 = .85 x 15 x 1.34 = 17.1 ml O2/dl

Patient A, with the higher PaO2, is more hypoxemic.


Full formula: Ca02 = (Hgb)(1.34)(Sa02) + (0.0031)(Pa02)

Tuesday November 17, 2009

Q: What is the biggest danger while evaluating CXR with subcutaneous emphysema?

Answer: Missing underlying pneumothorax

The air may interdigitate with the muscle bundles to produce a characteristic linear streaky pattern, especially in the pectoralis muscles over the chest. When the streaky linear densities become widespread over the anterior and posterior chest walls, subcutaneous emphysema can obscure underlying pleural white line of a pneumothorax.

Monday November 16, 2009

Q: What is the salvage treatment for severe pruritis in cirrhotic patient if all coventional and non-conventional treatment fails?

Answer: Plasmapheresis



References:

1. Plasmapheresis in the treatment of cholestasis-induced pruritus Ugeskr Laeger. 2006 Feb 20;168(8):779-81.

2. Role of plasmapheresis in the treatment of severe pruritus in pregnant patients with primary biliary cirrhosis: case reports - Can J Gastroenterol. 2008 May;22(5):505-7.

3. Plasmapheresis for the treatment of intrahepatic cholestasis of pregnancy refractory to medical treatment - American Journal of Obstetrics and Gynecology, Volume 192, Issue 6, Pages 2088-2089

Sunday November 15, 2009


Short but interesting video of
Alveolar recruitment with PEEP

Saturday November 14, 2009
How Wound V.A.C. Therapy System works

The V.A.C. Therapy System is comprised of three essential components that actively work together to help induce cellular wound healing through promotion of granulation tissue formation.

1. V.A.C. Therapy Unit Provides intermittent and continuous therapy with integrated patient safety features
2. SensaT.R.A.C.™ Technology Regulates pressure at the wound site to provide accurate delivery of prescribed therapy settings
3. V.A.C. GranuFoam™ Dressings Help induce the necessary mechanisms to promote granulation tissue formation

How V.A.C. Therapy Works on the Cellular Level

Under negative pressure, V.A.C. Therapy with V.A.C. GranuFoam Dressings applies both mechanical and biological forces to the wound to create an environment that promotes wound healing. These forces are known as macrostrain and microstrain.

Macrostrain is the visible stretch that occurs when negative pressure contracts the foam. Macrostrain

• Draws wound edges together
• Provides direct and complete wound bed contact
• Evenly distributes negative pressure
• Removes exudate and infectious materials

Microstrain is the microdeformation at the cellular level, which leads to cell stretch. Microstrain:

• Reduces edema
• Promotes perfusion
• Increases cellular proliferation and migration
• Promotes granulation tissue formation
  

Friday November 13, 2009
Central line complication

A 40-year-old man with Crohn's disease underwent an uncomplicated operation involving lysis of adhesions that were causing intestinal obstruction. After surgery, a cardiologist inserted a central venous catheter through the left subclavian vein. No problems with catheterization were noted. Three weeks later, after discharge, mild pain and edema developed in the patient's right lower leg. He was treated with antibiotics for 1 week, and his symptoms diminished. Six months after the operation, the patient presented with posterior cervical pain. A guide wire, presumably lost during the insertion of the central venous catheter, was protruding from the back of his neck (Panel A, arrow). A computed tomographic scan showed the fractured guide wire in the central venous system (Panel B, arrows). The wire protruding from the back of the neck was removed easily; however, it was difficult to remove the part of the wire involving the saphenous vein, and an open procedure with general anesthesia was required. The involved leg vein was thrombosed and occluded. At 1 year of follow-up, the patient was free of symptoms and signs.

Source:

Guo H, Lee JD, Guo M. Guidewire loss: mishap or blunder? Heart 2006;92:602-602