Saturday December 19, 2009
The Impella - minimally invasive, catheter-based cardiac assist device

The Impella is a minimally invasive, catheter-based cardiac assist device designed to directly unload the left ventricle, reduce myocardial workload and oxygen consumption, and increase cardiac output and coronary and end-organ perfusion.

The Impella can be inserted into the left ventricle in a Cath Lab via a standard guidewire through the femoral artery, into the ascending aorta, across the valve and into the left ventricle.The tip of the catheter contains a “pigtail” that crosses the patient’s heart valve and rests in the left ventricle, generating flows up to 2.5 L/min. The Impella is hemocompatible, does no compromise to valve function. There is low hemolysis, bleeding, and stroke rates.

Friday December 18, 2009
Examination of the Neck Veins

Thursday December 17, 2009


Q: Lab call you with result that patient's pleural fluid has cholesterol level more than 45 mg/dL (1.16 mmol/L). What does it mean?


A; Pleural fluid is probably an exudate.

Using a cutoff point of 45 mg/dL for pleural cholesterol and/or LDH over 200 IU/L identified exudates with a sensitivity of 99% and a specificity of 98%.


Measurement of Pleural Fluid Cholesterol and Lactate Dehydrogenase - A Simple and Accurate Set of Indicators for Separating Exudates From Transudates - CHEST November 1995 vol. 108, no. 5 1260-1263

Wednesday December 16, 2009

Q: What is the mechanism of action of Mannitol in control of Intracranial Hypertension (Increase ICP)?


A; Immediately after bolus administration Mannitol expands circulating volume by help of osmotic forces, decreases blood viscosity, resulting in reflex vasoconstriction and lowering of intracranial pressure. Its osmotic properties take effect in 15-30 minutes when it sets up an osmotic gradient and draws water out of neurons.

Tuesday December 15, 2009

Q: Does Phenytoin (Dilantin) get cleared by hemodialysis or hemoperfusion?


A; No (clinically insignificant removal)

Clinical significance:

• In Phenytoin toxicity/overdose, Hemodialysis or hemoperfusion are ineffective for enhancing elimination.
• Hemodialysis patients do not require extra dosing post dialysis though require frequent monitoring due to lower albumin level.

Monday December 14, 2009
Abnormal sleep and errors more common in ICU nurses

Intensive care unit (ICU) nurses are more likely than floor nurses to have abnormal sleep and to experience a drop in vigilance during their shift that could impair patient safety, according to study findings presented at the CHEST 2009 meeting in San Diego, California.

"Nurses working in the ICU tend to have abnormal sleep and tend to have a greater frequency of errors across the length of their shift," lead researcher Dr. Salim R. Surani said. "These findings could be explained on the basis of the ICU nurses having a more impaired sleep quality as seen by PSQI (Pittsburg Sleep Quality Index), and perhaps having a more demanding and intensive work schedule in the ICU as compared to the floor."

Dr. Surani and colleagues from Baylor College of Medicine, Houston assessed ICU and floor nurses using the psychomotor vigilance test (PVT)

• ICU nurses made more errors at both the beginning and end of their shift than did floor nurses.
• As their shifts progressed, the ICU nurses made more errors (p = 0.029), while floor nurses showed no change.
• ICU nurses had significantly worse PSQI scores than did floor nurses (p = 0.041).
• Scores on the Epworth and Stanford sleepiness scales, however, were similar in the two groups.

Dr. Salim Surani is co-editor of this website and extensively published on 'sleep'.

Sunday December 13, 2009


Q: Describe relationship between Hypoxemia and acute Decompensated Right Ventricular Failure?

Answer: Oxygen is the most potent pulmonary vasodilator and liberal oxygen administration will reduce pulmonary vascular resistence and improve cardiac output.