Q: What is "wedged blood PO2" and what is the clinical implication?


Answer: "Wedged blood Po2" is the level of PO2 while Pulmonary artery catheter baloon is inflated (wedging).

Wedge blood Po2 should be atleast 20 mm Hg higher than arterial PO2 (ABG) to confirm that you are measuring Pulmonary artery occlusion pressure at right level/spot.




Reference:

Paul L. Marino - The little ICU book of facts and Formulas, 2009 - Page 119

Q: 52 year old male developed intracranial hemorrhage after receiving thrombolytic therapy for CVA. What is the treatment?


Answer: Transfusion of cryoprecipitate.

Prepare for administration of 6 to 8 units of cryoprecipitate containing factor VIII. It is not a bad idea to also adminster 6 to 8 units of platelets.

Holiday Heart Syndome

Holiday Heart Syndome was originally defined as "arrhythmias of the heart, sometimes apparent after a vacation or weekend away from work, following excessive alcohol consumption; usually transient". Same has been reported with recreational use of marijuana. The most common rhythm disorder is atrial fibrillation, which usually converts to normal sinus rhythm within 24 hours. It occurs in patients without structural heart disease and its clinical course is usually benign. Even modest alcohol intake may trigger paroxysmal atrial fibrillation.

Most patients with no evidence of structural heart disease can be discharged without further treatment once arrhythmia has stabilized with advise against the excessive use of alcohol. Patients with sustained tachyarrhythmia require treatment if the ventricular rate is excessive. Patients with structural heart disease needs further workup.

Q: Steroids and diuretics are indicated in treatment of Transfusion-related acute lung injury (TRALI)

A) True
B) False



Answer: False

So far there is no evidence that steroids are helpful in TRALI. Another mistake would be to administer diuretics. TRALI is associated with microvascular damage and not fluid overload, so diuretics are not really helpful and actually not recommended. Since the pulmonary edema in TRALI is not related to fluid overload or cardiac dysfunction, it is logical that maintenance of adequate circulating volume is more beneficial - so it may even require IV fluid. Ventilatory assistance and circulatory support are the mainstays of treatment of TRALI. Diuretic use may be detrimental and could lead to hypotension.

TRALI is essentially a clinical diagnosis but one laboratory finding may include sudden fall in serum albumin.

Ultrasound for Arterial lines - no brainer

Ultrasound guided placement of CVCs (central venous catheters) is now pretty much a standard in ICUS - at least in USA but fewer clinicians are using it for arterial catheterization.

This month of 'chest' has published a meta-analysis of 4 trials with a total of 311 subjects were included in the review, with 152 subjects included in the palpation group and 159 in the ultrasound-guided group.

Results showed that compared with the palpation method, ultrasound guidance for arterial catheterization was associated with a 71% improvement in the likelihood of first-attempt success.


Ultrasound-Guided Catheterization of the Radial Artery, A Systematic Review and Meta-analysis of Randomized Controlled Trials, Ariel L. Shiloh, MD, Richard H. Savel, MD, Laura M. Paulin, MD, MHS and Lewis A. Eisen, MD, FCCP. From the Division of Critical Care Medicine, Montefiore Medical Center and the Albert Einstein College of Medicine, Bronx, NY

Q; Which commonly use drugs in ICU may cause resistance to Heparin Therapy (failure of monitoring tests to change or higher than expected doses) ?


Answer: The most important cause of apparent resistance to heparin therapy is antithrombin III deficiency. Replacement of antithrombin III in a deficient patient may restore heparin efficacy.

Also, its important to know that following commonly use medicines may cause resistance to heparin therapy.

• intravenous nitroglycerin
• digitalis,
• nicotine (smoking),
• tetracycline
• some antihistamines
  

Reference:

Bick RL., Disorders of Thrombosis & Hemostasis. Clinical and Laboratory Practice. 1992. ASCP Press. (Figure 1-29 page 20; Table 14-7, page 305).

Lasix - bolus or continuous infusion?

Very interesting study published recently in NEJM looking into diuretic strategies in patients with acute decompensated heart failure.

In a prospective, double-blind, randomized trial, 308 patients with acute decompensated heart failure were assigned to receive furosemide administered intravenously by means of either a bolus every 12 hours or continuous infusion and at either a low dose (equivalent to the patient's previous oral dose) or a high dose (2.5 times the previous oral dose). The protocol allowed specified dose adjustments after 48 hours.

In the comparison of bolus with continuous infusion, there was no significant difference in patients' global assessment of symptoms or in the mean change in the creatinine level.

In the comparison of the high-dose strategy with the low-dose strategy, there was a nonsignificant trend toward greater improvement in patients' global assessment of symptoms in the high-dose group. The high-dose strategy was associated with greater diuresis and more favorable outcomes in some secondary measures but also with transient worsening of renal function.

It was concluded that among patients with acute decompensated heart failure, there were no significant differences in patients' global assessment of symptoms or in the change in renal function when diuretic therapy was administered by bolus as compared with continuous infusion or at a high dose as compared with a low dose.


Diuretic Strategies in Patients with Acute Decompensated Heart Failure, N Engl J Med 2011; 364:797-805, March 3, 2011

NE and Dobutamine or Epinephrine alone?

In a recent study published from France compared epinephrine and norepinephrine-dobutamine in dopamine-resistant cardiogenic shock. It was an open, randomized interventional human study.

Thirty patients with a cardiac index of less than 2.2 and a mean arterial pressure of less than 60 mm Hg who were resistant to combined dopamine-dobutamine treatment and signs of shock were included. Patients were randomized to receive an infusion of either norepinephrine-dobutamine or epinephrine titrated to obtain a mean arterial pressure of between 65 and 70 mm Hg with a stable or increased cardiac index.

It was found that

• both regimens increased cardiac index and oxygen-derived parameters in a similar manner.
• Patients in the norepinephrine-dobutamine group demonstrated heart rates lower than those in the epinephrine group.
• Epinephrine infusion was associated with new arrhythmias in three patients.
• When compared to baseline values, after 6 hrs, epinephrine infusion was associated with an increase in lactate level, whereas this level decreased in the norepinephrine-dobutamine group.
• Tonometered PCO2 gap, a surrogate for splanchnic perfusion adequacy, increased in the epinephrine-treated group while decreasing in the norepinephrine group.
• Diuresis increased in both groups but significantly more so in the norepinephrine-dobutamine group, whereas plasma creatinine decreased in both groups.
  

It was concluded that when considering global hemodynamic effects, epinephrine is as effective as norepinephrine-dobutamine. Nevertheless, epinephrine is associated with a transient lactic acidosis, higher heart rate and arrhythmia, and inadequate gastric mucosa perfusion. Thus, the combination norepinephrine-dobutamine appears to be a more reliable and safer strategy.

Comparison of norepinephrine-dobutamine to epinephrine for hemodynamics, lactate metabolism, and organ function variables in cardiogenic shock. A prospective, randomized pilot study - Critical Care Medicine: March 2011 - Volume 39 - Issue 3 - pp 450-455

Percutaneous Aortic Valve Replacement!!
(Corevalve)

Q: What is the quick way of suspecting Pancreatitis secondary to alcohol intake?


Answer: The lipase/amylase ratio. A lipase/amylase ratio of greater than 2 suggests alcoholic pancreatitis.

note: many sources question the reliability of this ratio.

Q: What is Fox's sign?

Answer: Fox's sign is ecchymotic patches seen over the inguinal ligament or the anterolateral surface of one or both thighs just below the inguinal ligament. The discoloration results from bloody fluid tracking extraperitoneally along the fascia of the psoas and iliacus muscles, becoming subcutaneous in the upper thigh. It occurs in patients with retroperitoneal bleeding, usually due to acute haemorrhagic pancreatitis. The sign is named after Dermatologist, Dr. Fox.

Case: 72 year old male presented after midnight when ancillary services (ultrasound or CT scan) are not available. Initial diagnosis is pneumonia with pleural effusion. What may help you in deciding "to tap or not to tap" (thoracentesis) the patient?



Answer: If there is a confusion about 'size of' pleural effusion, obtain lateral decubitus film. Measure the width of the layering pleural fluid. If the width of the fluid is less than 10 mm, the effusion can be managed medically or thoracentesis may be deferred. And if the effusion is wider than 10 mm, thoracentesis is recommended.

Case: 32 year old lean thin man presented to ED with 4 days of "Right" sided chest pain associated with shortness of breath. CXR showed sponteneous pneumothorax (PTX) on "Right" side. Chest tube is inserted with immediate resolution of PTX. 2 hours later patient complaint of shortness of breath again. Physical exam shows crackles on "Left " side?


Answer: "Contralateral" Reexpansion Pulmonary Edema

Reexpansion pulmonary edema (REPE) is a rare but known complication of evacuation of pleural effusion or pneumothorax. Usually it occurs on same side or both side but it may occur only in contralateral lung. Mechanism for this phenomenon is not known.

Risk for REPE is high if lung is collapsed for more than 3 days. If its secondary to pleural effusion it is recommended to remove no more than 1 liter of fluid. The treatment is supportive with supplemental oxygen, positive pressure ventilation, and diuresis.