Sunday May 17, 2009

Cardaic enzymes with and without perfusion

Saturday May 16, 2009


Insertion Of Laryngeal Mask Airway

Friday May 15, 2009 (pediatric pearl)
Weaning and Extubation in Children: Some Facts

Over 50% of ventilated PICU patients will have been extubated by 48 hrs after admission, but the rest often require prolonged ventilatory support. Failed planned extubations in the latter group average 8.0% but range up to 20% in some studies. Conversely, 50% of unplanned extubations end in success, implying that some patients could be extubated earlier.

Not all patients require gradual weaning. Both adult and pediatric studies have shown that when patients pass a SBT and are subjected to an ERT, 50%–75% of the patients are deemed ready to extubate.

* There are no infallible predictive tests for successful extubation. The RSBI has become moderately popular but since there is a wide range of age groups with different respiratory rates it may not be a good predictor of extubation success or failure in the pediatric population. Whether age-specific f/VT ratio is better is currently unknown.

* Adult studies show that T-piece or PS trials for an ERT are equally effective; IMV or SIMV are not deemed as useful. Pediatric studies have led to similar conclusions.

* Use of a weaning protocol results in faster weaning in adults. Although the data are less clear in children, it is likely a consistent approach to ventilator weaning will shorten ventilator time and result in better outcomes.

* A recent Cochrane Review on the role of steroids concludes : “Using corticosteroids to prevent (or treat) stridor after extubation has not proven effective for neonates, children or adults. However, given the consistent trend toward benefit, this intervention does merit further study”


Reference: click to get abstract

Weaning and extubation readiness in pediatric patients - Pediatric Critical Care Medicine. 10(1):1-11, January 2009

Thursday May 14, 2009

Scenario: 39 year old male developed 10% right sided pneumothorax with no major clinical signs after subclavian central line placement. Conservative observation with application of NR-mask didn't resolve the pneumothorax but actually now size has increased to 30%. You inserted chest tube with resolution of pneumothorax and proper chest tube placement as documented by immediate CXR at bedside. 10 minutes later patient went into shortness of breath. On clinical exam, bilateral breath sounds are audible but with rales more pronounced on right side. While waiting for repeat CXR, your probable diagnosis?



Answer: Re-expansion pulmonary edema (REPE)

REPE is a rare complication occurring after the insertion of a chest tube for pneumothorax or pleural effusion. REPE can occur on the ipsi- or contralateral side, can be bilateral and can even be asymptomatic.

The exact pathophysiology for this complication is unknown. Oxygen radicals are produced during the hypoxemia in the collapsed lung. Moreover, the activity of different cytokines have been implicated in the pathogenesis of REPE.

Major risk factors associated with REPE:

• younger age ( less than40 years),
• longer duration of lung collapse ( more than4 days),
• large pneumothorax ( more than 30% of a single lung)

Reference: click to get article

1. Ipsilateral reexpansion pulmonary edema after drainage of a spontaneous pneumothorax: a case report - J Med Case Reports. 2007; 1: 107. Published online 2007 September 29

Wednesday May 13, 2009


Extrapontine myelinolysis from severe hyponatremia

(a) Normal MRI scan taken five months before the episode of severe hyponatremia, when serum sodium was 140 mmol/l.

(b) Ten days after the episode of severe hyponatremia, MRI scan showed bilateral high-intensity abnormalities in the lenticular nuclei and in the head of the caudate nucleus (arrows).

(c) At day 32, the lesions shown in panel b appear more pronounced (arrows).

(d) At day 32 with fluid-attenuation inversion recovery, high intensity lesions were also observed in the precentral gyrus (arrows).



Reference: Click to get article

Severe hyponatremia followed by extrapontine myelinolysis - Kidney International (2006) 69, 423.

Tuesday May 12, 2009
Does C-reactive protein Helps in ARDS

Study by Bajwa helped to sort the issue out. They measured C- reactive protein levels in 177 patients within 48 hours of disease onset, and measured 60 day mortality, 28 day daily organ dysfunction, and number of ventilator free days.


Results:

• C- reactive protein was significantly lower in non-survivors (p=0.02).
• Mortality rate decreased with increase in C-reactive protein deciles (p=0.02)
• Increasing C-reactive protein was associated with increase in 60 days mortality.
• Patient with high C-reactive protein had significantly lower organ dysfunction score (p=0.001) and more ventilator free days (p=0.02).
  
  

Conclusion: Increased C-reactive protein is good.



Reference: Bajwa EK, Khan AK, Januzzi JL, Gong MN et al. Plasma C-reactive protein levels are associated with improved outcome in ARDS. Chest May 2009 published online before print

Monday May 11, 2009
Ventricular Assist Device in the ICU

“Mechanical circulatory support aims to preserve life, restore, circulation provide optimal blood supply to metabolizing tissues, normalize organ function, and allow the heart to recover from an acute insult, and acute decompensation, or a progressive decline of a chronic disorder, without adding further compromise.”

1. Timing of intervention: short term vs. long term: Bridge to recover, to surgery, to transplantation, or to decision

2. Device and patient management: Goal of device implantation is to ensure optimal organ perfusion and ventricular decompression. Total systemic circulation output should exceed 2.2 L/min/m2, SVO2 more than 70%

2a. To achieve this, preload must be optimize

• Diuresis to prevent third spacing
• Maintain adequate intravascular volume with fluids, albumin, blood products to correct anemia

2b. Improve/preserve right ventricular function with diuretics,
arrhythmia treatment, avoiding, perioperative myocardial
ischemia, stunning, acidosis, and transfusions

3. Infection: A significant source of morbidity and mortality is infection. Prevent infection by removing indwelling lines and catheters as soon as possible, antibiotic prophylaxis, meticulous sterile techniques and dressing changes, driveline stablilization, early extubation and mobilization, and nutrition support.

4. Anticoagulation: All devices require heparin in the first 24-48 hours post implantation or after cessation of postoperative bleeding. Temporary devices should continue with heparin until decision is made. Long term devices should be converted from heparin to anticoagulant or antiplatelet pending type of device implanted.


Reference: Pitsis AA, et al. Update on ventricular assist device management in the ICU. Curr Opinion in Crit Care. 2008;14:569-578.

Sunday May 10, 2009


Q: 47 year old male is brought to ER with fever and mental status change. Patient did not produce any urine while foley was inserted. Lab is still pending. A research student made following slide in ER. What is your presumptive diagnosis?


.

Answer: Thrombotic thrombocytopenic purpura (TTP)

TTP is a life-threatening condition which may have a positive outcome if recognized early and medical intervention is initiated early with plasma exchange.

The classic pentad associated with TTP (fever, renal failure, neurological change, thrombocytopenia and microangiopathic hemolytic anemia) are not always easy to recognize. Lab finding of elevated LDH and schistocytosis (arrows in picture above) are very crucial for diagnosis of TTP.

Saturday May 9, 2009


Q: Which commonly use anti-seizure medicine is not effective or actually has been advise not to use in seizures secondary to Lidocaine?

Answer: Phenytoin (Dilantin)

In seizures secondary to lidocaine, benzodiazepines and barbiturates are the drugs of choice. Phenytoin is not effective.

Friday May 8, 2009 (pediatric pearl day)
Outcome of septic shock in the neonatal period

Septic shock in the neonatal period has a very poor outcome.

Study n = 48

The 28-day mortality was 40%. Adverse outcome at 18 months of corrected age was observed 52% cases (death = 19, severe sequelae = 5). 28% of the infants were alive and had a normal examination at 18 months.

Significant predictors (multivariate analysis) of 28-day mortality and of adverse outcome at 18 months of corrected age were:

• Weight (kg) at the onset of sepsis
• Gram-negative infection

Conclusions: Data underscore the extreme vulnerability of very low birth weight infants to septic shock, particularly to Gram-negative species.




Reference:

Outcome and prognostic factors in neonates with septic shock - Pediatric Critical Care Medicine. 9(2):186-191, March 2008

Thursday May 7, 2009
Influence of positive end-expiratory pressure (PEEP) on left ventricular regional wall motion in patients with acute respiratory distress syndrome (ARDS)

Regional left ventricular wall motion abnormalities have been described with positive end-expiratory pressure (PEEP). Study was conducted to assess global and regional LV performance in response to PEEP by transoesophageal echocardiography (TOE) in patients with ARDS. Study was conducted on eight critically ill patients with normal systolic LV function requiring mechanical ventilation (tidal volume 6-8 ml/kg, PEEP 12 ± 2 cmH2O) due to ARDS.

Measurements: Regional and global LV performance were assessed at PEEP levels of 5, 10, 15, 20 and 25 cmH2O.

Results: PEEP =15 cmH2O produced a significant reduction in systolic septal wall motion (hypokinesia) and a significant augmentation of lateral systolic wall motion (hyperkinesia). Global LV performance - measured as fractional area change - was not significantly affected.



Reference: Click to get abstract

Influence of positive end-expiratory pressure (PEEP) on left ventricular regional wall motion in patients with acute respiratory distress syndrome (ARDS): from 22nd International Symposium on Intensive Care and Emergency Medicine, Brussels, Belgium. 19–22 March 2002 Critical Care 2002, 6(Suppl 1):P14

Wednesday May 6, 2009

Q; EKG below shows characteristics of which electrolyte abnormality?

Answer: Hypokalemia

This EKG shows

• a long QT interval,
• ST depression,
• low T waves, and
• TU wave fusion

all characteristics of Hypokalemia.

Tuesday May 5, 2009


Q; What are 2 types of Atrial flutter?

Answer:

Type I atrial flutters (tricuspid valve isthmus dependent): Catheter ablation is typically successful and recurrence is less than 5%. Postprocedure anticoagulation with warfarin is usually continued for 4-6 weeks.

Type II atrial flutters (non—tricuspid valve isthmus dependent): These circuits are amenable to catheter ablation but require advanced mapping systems. Recurrence is more common and may also require the use of antiarrhythmic agents for suppression.

Monday May 4, 2009
Transdermal patch burn and MRI

Certain transdermal patches contain aluminum or other metals in the backing of the patches. Patches that contain metal can overheat during an MRI scan and cause skin burns in the immediate area of the patch. Patches usually contain metal in the layer of the patch that is not in contact with the skin (the backing).
Following patches have been identified by FDA.

Catapres TTS

(Clonidine)

Neupro

(Rotigotine)
Lidopel

(Lidocaine HCl and epinephrine)
Synera

(Lidocaine/Tetracaine)
Transderm-Scop

(Scopolamine)
Prostep

(Nicotine transdermal system)

Habitrol

(Nicotine transdermal system)

Nicotrol TD

(Nicotine transdermal system)
Androderm

(Testosterone transdermal system)
Fentanyl

(Fentanyl)

Salonpas Power Plus

(Methyl Salicylate/Menthol)

Reference:

1. FDA Public Health Advisory Risk of Burns during MRI Scans from Transdermal Drug Patches with Metallic Backings - fda.gov

Sunday May 3, 2009
Drug -Drug interaction / cardiology

Q: Which two commonly use drugs in CHF (congestive heart failure) - may oppose each other's action?

Answer: Aspirin and Furosemide (Lasix)

Lasix has a direct vasodilator effect and this effect begins within a few minutes after an administration of IV Lasix. This added effect is very useful in treatment of acute pulmonary congestion. But this desirable action can be blocked by nonsteroidal anti-inflammatory drugs including aspirin.

Mechanism of action is not clear but salicylates may inhibit the renal effects of loop diuretics that are mediated by prostaglandins, including increases in sodium excretion, renal blood flow, and plasma renin activity.

Read interesting commentary on this issue: Aspirin Use in Chronic Heart Failure, What Should We Recommend to the Practitioner? (Barry M. Massie, MD - J Am Coll Cardiol, 2005; 46:963-966


References:

1. Jhund PS, Davie AP, McMurray JJ. Aspirin inhibits the acute venodilator response to furosemide in patients with chronic heart failure. J Am Coll Cardiol. 2001;37:1234-1238

2. Effect of combined administration of furosemide and aspirin on urinary urate excretion in man - Journal of Molecular Medicine, Volume 57, Number 23 / December, 1979, 1299-1301

Saturday May 2, 2009
Dermatology

Q: What is the medical term for "cool, clammy, and mottled skin" in cardiogenic shock due to vasoconstriction and subsequent hypoperfusion of the skin?

Answer: Cutis Marmorata

Friday May 1, 2009
Use of Nebulized Lidocaine for Nasogastric Tube Insertion - Pros and cons

A double-blind, placebo-controlled, randomized clinical trial of adult patients was conducted in the EDs of 2 university hospitals. 29 participants were administered nebulized lidocaine (4 mL 10%), and 21 participants received nebulized normal saline solution *. Patient discomfort was measured using a 100-mm visual analog scale. The difficulty of nasogastric tube insertion was evaluated using a 5-point Likert scale.

Results:

• There was a clinical and statistical significant difference in patient discomfort associated with the passage of the nasogastric tube between nebulized lidocaine and placebo groups (mean visual analog scale score 37.7 versus 59.3 mm, respectively).
• There was not a detectable difference in difficulty with the passage of the nasogastric tube between the 2 groups
• Epistaxis occurred more frequently in the lidocaine group

Conclusion: Nebulized lidocaine decreases the discomfort of nasogastric tube insertion and should be considered before passing a nasogastric tube. An increased frequency of epistaxis, however, may be associated with its use.

* Four milliliters of the trial solution was administered using a face mask and a compressed gas-powered jet nebulizer with an oxygen flow rate of 6 L/min. The patient was instructed to breathe through his or her nose and mouth while the solution was being nebulized. Immediately after the nebulization was completed, the nurse removed the mask and inserted the nasogastric tube with the usual lubrication gel (KY Jelly) in the normal manner.



Reference: Click to get abstract

Nebulized Lidocaine Decreases the Discomfort of Nasogastric Tube Insertion: A Randomized, Double-Blind Trial - [Ann Emerg Med. 2004;44:131-137.]