Wednesday, November 30, 2005

Wednesday November 30, 2005
Haloperidol (Haldol) intra-venous (IV)

Use of IV Haloperidol is a common practice in ICUs but it is approved by FDA - Food and Drug Administration - for only intra-muscular (IM) use. Yes ! "IV Haldol" is still off-label.

References: click to get abstract/article
1.
HALDOL- DOSAGE AND ADMINISTRATION - rxlist.com

Monday, November 28, 2005

Tuesday November 29, 2005
Euthyroid Sick Syndrome

Word of wisdom is not to check thyroid function test in ICUs as it takes only few hours for patient to ‘abnormalize’ thyroid function test under stress but if clinically indicated send full "Thyroid Function Test” including TSH, Total T3, Total T4, Free T4 and rT3 (reverse T3). There is no absolute trend but general rule of thumb is as patient get sicker and sicker “all fall but reverse rise” i.e rT3 (reverse T3) will be elevated.


References: click to get abstract/article
1.
Sick euthyroid syndrome - Jennifer Best M.D - Harborview Medical Center, seattle, Washington - University of Washington, Div. of General Internal Medicine.
2.
Euthyroid Sick Syndrome - Serhat Aytug, MD - (please register free at emedicine.com)
Monday November 28, 2005
Four Phases of Acetaminophen Toxicity And Rumack-Matthew Nomogram (revised).


Acetaminophen (Tylenol, Paracetamol) toxicity is divided into four phases time-wise.

Phase 1 (up to 24 hours): Mild symptoms

Phase 2 (24- 48 hours): Right upper quadrant pain and rising Liver enzymes with deteriorating symptoms.

Phase 3 (48-96 hours): Liver failure

Phase 4 (4 days to 3 weeks): Resolution or death.

Clinical Significance: Patient’s Acetaminophen level should be plotted on Rumack-Matthew nomogram (revised) during first 24 hours of ingestion and if it falls in "possible" or "probable" liver failure risk area of nomogram, hepatology team should be alerted (or transfer to tertiary care center with liver services) as clinical deterioration may unfold very quickly.


Rumack-Matthew nomogram (revised) is available in the reference article below.

References: click to get abstract/article
1.
Acetaminophen Intoxication and Length of Treatment: How Long Is Long Enough? - Pharmacotherapy 23(8):1052-1059, 2003 (available via medscape.com with free registration).

Sunday, November 27, 2005

TOF

Sunday November 27, 2005
Can we go without Train of Four (TOF) ?

On literature search we found atleast 2 decent (though small) studies questioning the need of Train of Four (TOF) which is considered so far to be the standard of care while patient on continuous- infusion neuromuscular blocking agents (NMB).


1. Div. of Pulm. & CCM, Med. Univ. of South Carolina, Charleston - compared 20 patients with TOF and 16 patients with best clinical assessment group and found no difference. (NMB used was Atracurium).

2. Div. of Pulm. & CCM, Univ. of Mississippi Med. Center, Jackson - compared 16 patients with TOF and 14 patients with best clinical assessment group and found no difference. (NMB used was cisatracurium).

But strong arguments made in favour of TOF by Dr. Sessler is also worth reading. (Click Ref. 3)


See nice article covering most aspect on TOF
here from Dimensions of Critical Care Nursing.

References: click to get abstract/article
1.
Comparison of Train-of-Four and Best Clinical Assessment during Continuous Paralysis - Am. J. Respir. Crit. Care Med., Volume 156, Number 5, November 1997, 1556-1561
2.
A Prospective Randomized Comparison of Train-of-Four Monitoring and Clinical Assessment During Continuous ICU Cisatracurium Paralysis - Chest. 2004;126:1267-1273
3.
Train-of-Four To Monitor Neuromuscular Blockade? - Curtis N. Sessler, MD, FCCP - Chest. 2004;126:1018-1022.
4.
An Algorithm for Train-of-Four Monitoring in Patients Receiving Continuous Neuromuscular Blocking Agents - Dimensions of Critical Care Nursing, March/April 2003 Volume 22 Number 2 Pages 50 - 57

Saturday, November 26, 2005

Saturday November 26, 2005
Is post pyloric feeding absolute ?

It is not uncommon to find a patient in ICU to go without nutrition for long time only because enteral feeding tube (e.g. dobhoff) is not cleared by x-ray for post pyloric placement. Drs. Marik and Zaloga did meta-analysis of 9 prospective randomized controlled trials of 522 patients from medical, neurosurgical and trauma ICUs and found no difference in incidences of pneumonia, ICU length of stay and mortality between 2 groups (gastric and post-pyloric). Major recommendation made was: Patients who are not at high risk for aspiration should have a nasogastric/orogastric tube placed as early as possible for the initiation of enteral feeding. Small intestinal feeding tube should be considered if patient remain intolerant of gastric tube feeding despite addition of promotility agents or patients who demonstrate significant reflux or documented aspiration.


References: click to get abstract/article
Gastric versus post-pyloric feeding: a systematic review - Critical Care 2003, 7:R46-R51

Friday, November 25, 2005

Friday November 25, 2005
Acute acalculous cholecystitis in ICU

Diagnosis of acute acalculous cholecystitis (AAC) remains one of the most life saving skill in ICU as mortality from gallbladder rupture within 48 hours is high. Data of 39 patients published from Finland provide pretty good idea of patients prone to develop AAC. 1

1. Infection was the most common admission diagnosis, followed by cardiovascular surgery.
2. The mean APACHE II score on admission was 25.
3. The mean length of ICU stay before cholecystectomy was 8 days.
4. 85% of the patients received norepinephrine infusion.
5. 90% of the patients suffered respiratory failure before cholecystectomy.

Champagne Sign in acute acalculous cholecystitis: (On ultrasound) emphysematous cholecystitis with gas bubbles arising in the fundus of the gallbladder.

See nice review article on
acalculous cholecystitis from emedicine.com (please register - free).

References: click to get abstract/article
1.
Acute acalculous cholecystitis in critically ill patients - Acta Anaesthesiologica Scandinavica, 2004 Sep;48(8):986-91 - from pubmed -. Acta Anaesthesiologica Scandinavica is an official publication of The Scandinavian Society of Anaesthesiology and Intensive Care Medicine.

Thursday, November 24, 2005

Thursday November 24, 2005
Saline vs Albumin - SOAP trial

As we know that in SAFE trial (Saline vs Albumin Fluid Evaluation) there was some positive trend for albumin in severe sepsis subset patients but overall 28-days outcome was “no difference”. But this month results of SOAP (Sepsis Occurrence in Acutely ill Patients) study - with caution of various limitations to study - showed negative trend for albumin with conclusion: “Albumin administration was associated with decreased survival in this population of acutely ill patients”. Negative trend may be due to cardiac depression from decreased ionic calcium, impaired renal function
and anti-thrombotic properties of albumin. Probably the real answer is bedside clinical judgement for each patient.

References: click to get abstract/article
1.
A Comparison of Albumin and Saline for Fluid Resuscitation in the Intensive Care Unit - NEJM, May 2004 Volume 350:2247-2256
2.
Is albumin administration in the acutely ill associated with increased mortality? Results of the SOAP study - Critical Care 2005, 9:R745-R754

Wednesday, November 23, 2005

Wednesday November 23, 2005
SRMD and PUD

We commonly use terms Stress ulcer (Stress Related Mucosal Disease = SRMD) and Peptic ulcer (PUD) interchangeably in ICU while talking "GI prophylaxis". But both are 2 different conditions. (Probably what we are worried in our "unit" patients is mostly SRMD).

SRMD is multiple superficial erosions occurring in proximal gastric bulb involving superficial capillaries secondary to mucosal hypoperfusion and perforations are rare.

PUD is few deep erosions occurring usually in duodenum involving one vessel secondary to other reasons (drugs, H.Pylori, hypersecretory states etc.) and perforation is common.

From Dr. David C. Metz, nationally renowned in Acid-Peptic Diseases, lecture in Aspire 2005 (Acid Suppression Pharmacotherapy in the ICU: Re-evaluating the Evidence), an initiative to provide a critical assessment of the most current data on therapeutic approaches in acid suppression and the prevention of peptic ulcer rebleeding and stress-related mucosal disease. Launch Aspire 2005 here. Highly recommended for Critical Care nurses and house-staff.

Tuesday, November 22, 2005

Tuesday November 22, 2005
Early CRRT in septic shock

A recent observational study of 60 patients from france is published in
ccforum (november, 2005) regarding early initiation of continuous veno-venous haemodiafiltration (CVVHDF), in patients meeting at the same time criteria for sepsis, refractory circulatory failure, acute renal injury, and acute lung injury. CVVHDF was started after 6–12 hours of full haemodynamic support. There are 3 interesting conclusions:

1. In patients showing improvement in metabolic acidosis after 12 hours of CVVHDF, with progressive improvement in organ failures; the final mortality rate was 30%.

2. Those patients who did not show any improvement in metabolic acidosis, mortality rate was 100%.

3. The crude mortality rate for the whole group (53%), was significantly lower than the predicted mortality using
Simplified Acute Physiology Score II (79%).

References: click to get abstract/article
1.
Early veno-venous haemodiafiltration for sepsis-related multiple organ failure - Critical Care 2005, 9:R755-R763
2. New Simplified Acute Physiology Score - from sfar.org site

Monday, November 21, 2005

Monday November 21, 2005
Sympathetic Storming


Sympathetic storming after traumatic brain injury remains one of the most dramatic clinical scene particularly in neurological units. It occurs due to uncontrolled sympathetic surge with a diminish or unmatch parasympathetic response. Acording to Baguley criteria 5 out of the 7 clinical features should be present - tachycardia, tachypnea, hyperthermia, hypertension, dystonia, posturing, and diaphoresis. Various agents have been used for treatment (see review article below) but haloperidol may worsen the symptoms.

Dr. Blackman and coll. coined the term "PAID" - paroxysmal autonomic instability with dystonia- in Archives of Neurology March 2004.


See great review article
here on Sympathetic Storming from Denise M. Lemke, published in J Neurosci Nurs 36(1):4-9, 2004. © 2004. . Also available in our "B" search section at www.icuroom.net.

References: click to get abstract/article
1.
Dysautonomia after traumatic brain injury: a forgotten syndrome? - J Neurol Neurosurg Psychiatry 1999;67:39-43 ( July )
2.
Paroxysmal autonomic instability with dystonia (PAID) - Arch Neurol. October 2004;61:1625.
3.
Paroxysmal Autonomic Instability with Dystonia After Brain Injury - Arch. Neurol. March 2004;61:321-328
4.
Riding Out the Storm: Sympathetic Storming After Traumatic Brain Injury - Denise M. Lemke, MSN CS-RN ANP CNRN - J Neurosci Nurs 36(1):4-9, 2004.

Sunday, November 20, 2005

Sunday November 20, 2005
Time lag between Linezolid and Thrombocytopenia


Thrombocytopenia could be multifactorial in ICU. One of the relative new cause is Linezolid (Zyvox). But thrombocytopenia with Zyvox usually doesn't occur upto 2 weeks with the initiation of treatment and could help in ruling out atleast one reason. Relatively overall its mild, reversible and due to myelosuppression. there is no evidence for anti-platelet or interference with platelet function.

References: click to get abstract/article
1.
Hematologic Effects of Linezolid: Summary of Clinical Experience - Antimicrobial Agents and Chemotherapy, August 2002, p. 2723-2726, Vol. 46, No. 8
2.
Linezolid and reversible myelosuppression. - JAMA 285:1291
3.
Safety, efficacy and pharmacokinetics of linezolid for treatment of resistant Gram-positive infections in cancer patients with neutropenia - Annals of Oncology 14:795-801, 2003

Saturday, November 19, 2005

Saturday November 19, 2005
Drotrecogin Alfa (Activated) tie to APACHE Score


Drotrecogin Alfa (Activated) - Xigris - is without doubt an effective tool in treating sepsis but there are debates about "to do or not to do".

Irrespective of reservations regarding APACHE II score itself, it is important to know the results of study from ADDRESS Study Group (Administration of Drotrecogin Alfa (Activated) in Early Stage Severe Sepsis), which concluded that it should not be use in patients with APACHE II score less than 25. There was extra risk of bleeding without any benefit. Actually subset of same study found to have higher mortality (both 28-days and inpatient) in those patients who underwent recent surgery (within 30 days) and had only single organ failure - irrespective of APACHE score. There were significantly more bleeding events in the Xigris group.


See APACHE Scorings in our tools section at www.icuroom.net.

References: click to get abstract/article
1.
Drotrecogin Alfa (Activated) for Adults with Severe Sepsis and a Low Risk of Death - NEJM - Volume 353:1332-1341 - september 29, 2005.
2.
Warning from Xigris

Friday, November 18, 2005

Friday November 18, 2005
RU-486 and septic shock

As sepsis is a major bread n butter of intensivists, it may be of importance to know that abortion pill RU-486 (
Mifeprex/Mifepristone) has been associated with severe septic shock. 8 deaths (4 in USA) have been reported so far. 1 Mechanism of action is not entirely clear but it is secondary to pelvic infections from common vaginal bacteria Clostridium sordellii. Dr. Miech from Brown University proposed that Mifepristone, blocks both progesterone and glucocorticoid receptors and failure of physiologically controlled cortisol and cytokine response eventually results in release of toxins from C. sordellii and lead to life threatening septic shock. 2

References: click to get abstract/article
1.
Mifeprex (mifepristone) - FDA warning
2.
Pathophysiology of Mifepristone-Induced Septic Shock Due to Clostridium sordellii - The Annals of Pharmacotherapy: Vol. 39, No. 9, pp. 1483-1488

Thursday, November 17, 2005

Thursday November 17, 2005
Unplanned extubations - decrease mortality !

Interesting study published in
chest (august 2005) of 100 patients (compared to controlled group) who experienced unplanned extubation but did not require reintubation. They were found to have decrease mortality and remarkably good outcomes despite longer hospital and ICU stay.

Lesson learned: we are keeping our patients intubated longer than needed !!

References: click to get abstract/article
1.
The Drive to Survive - Unplanned Extubation in the ICU - From the Critical Care Unit (Dr. Krinsley), Stamford Hospital, Stamford, CT; and Department of Surgery (Dr. Barone), Columbia University College of Physicians and Surgeons, New York, NY.

Wednesday, November 16, 2005

amiodarone

Wednesday November 16, 2005
Am-iod-arone !!


The word "iod" in Amiodarone tells as that it is an iodine based compound. No wonder it mess up thyroid metabolism. Also, another interesting clinical significance of amiodarone toxicity is high-attenuation parenchymal-pleural lesions along with similiar increased attenuation in liver or spleen. This property of high attenuation due to iodine in lung, liver and spleen is pretty diagnostic of Am-iod-arone toxicity. The risk is higher if daily dose is greater than 400 mg. Amiodarone has increase half life in lung and eventually resolve with stoppage of drug while steroid is the thrapy in between. Acute Amiodarone toxicity has been described too.

See
CXR and non-contrast CT slice (but appearing as contrast due to iodine accumulation) in Amiodarone Toxicity - from Radiographics in reference 2 below.

References: click to get abstract/article
1.
Amiodarone pulmonary toxicity: CT findings in symptomatic patients - Radiology, Vol 177, 121-125
2.
Pulmonary Drug Toxicity: Radiologic and Pathologic Manifestations - Radiographics. 2000;20:1245-1259
3.
Amiodarone at pneumotox.com

Tuesday, November 15, 2005

Tuesday November 15, 2005
MAP measurement in ICU with sphygmomanometer

Although we don't need to do sphygmomanometric blood pressure measurement in ICUs on all patients anymore but still it is reasonable to have atleast one instrument available in "unit". (A-lines are not always inserted and sometime oscillometer readings don’t get register on monitor). Most experts agreed that MAP (Mean Arterial Pressure) is more of clinical significance - it may be of interest to know that beside traditional formula available to calculate MAP i.e. MAP = { SBP + (2DP) } / 3 OR DBP + .333 (SBP-DBP), there is another formula described which has been reported as more accurate.


MAP = DBP + .412 (SBP-DBP)

Here is the Nomogram to quickly find MAP with above formula without calculation. - reference - Heart 2000;84:64

References: click to get abstract/article
1.
Formula and nomogram for the sphygmomanometric calculation of the mean arterial pressure - Heart 2000;84:64 (July)
2.
Arterial Stiffness as Underlying Mechanism of Disagreement Between an Oscillometric Blood Pressure Monitor and a Sphygmomanometer - Hypertension. 2000;36:484
3.
Blood Pressure Measurement in Humans: A Statement for Professionals From the Subcommittee of Professional and Public Education of the American Heart Association Council on High Blood Pressure Research - Circulation. 2005;111:697-716

Monday, November 14, 2005

Monday November 14, 2005
Cameron lesions

Cameron lesions are linear gastric erosions positioned at the diaphragmatic impression, in patients with large hiatus hernia. It is a distinct entity from other erosions and was described first time about 20 years ago by AJ Cameron. Clinical significance: In upto one third of cases cameron lesions can present as acute upper GI bleed which may become life-threatening. Despite treatment, 33% develop recurrence of the lesion with possible acute event requiring immediate surgery. Lesion can also cause iron deficiency anemia and chronic GI bleed.


See endoscopic picture here - from Indian Journal of Gastroenterology.

References: click to get abstract/article
1.
Linear gastric erosion. A lesion associated with large diaphragmatic hernia and chronic blood loss anemia. - Gastroenterology. 1986 Aug;91(2):338-42.
2.
Hiatal hernia with cameron ulcers and erosions. - Gastrointest Endosc Clin N Am. 1996 Oct;6(4):671-9.
3.
Cameron lesion and its laparoscopic management - Indian J Gastroenterol 2005;24:163-163

Sunday, November 13, 2005

Sunday November 13, 2005
Potassium and phophate ratio in combo infusion


It is handy to remember that 1 mmol of intravenous phophate delivers 1.46 meq of potassium in "K-phos rider". To make it in round figure 7.5 mmol of phosphate is equal to about 10 meq of potassium and should be infuse over atleast one hour.

See nice read and guideline on "K-phos" rider at ismp.org

Saturday, November 12, 2005

Saturday November 12, 2005
Urinary Catheter related UTIs in ICU

There is a lot of emphasis on questioning everyday about nescessity of central venous lines but it may be of interest to know that urinary catheter related UTIs (urinary tract infections) makes 40% of hospital-acquired infections and 3% out of them ends up as bacteremia (and each episode of catheter-related nosocomial bacteremia costs a minimum of around US $3000). In ICUs, one recent study showed incidence density of 6 UCRI/1000 urinary catheter-days. (UCRI=urinary catheter related infection). In another study, implementation of nurse-driven surveillance of Criteria-Based Foley Catheter Guidelines (CFCG) protocol in ICU decreased UCRI from 6.4 to 1.9 per 1000 urinary catheter-days.


And no condom catheter are no better !

References: Click on link to get abstract/article:
1.
Urinary catheter-related infection in critically ill patients Critical Care 2005, 9(Suppl 1):P12
2.
Enhancing the Safety of Critically Ill Patients by Reducing Urinary and Central Venous Catheter-related Infections - American Journal of Respiratory and Critical Care Medicine Vol 165. pp. 1475-1479, (2002)
3.
The Effects of Criteria-Based Foley Catheter Guidelines in an ICU - Innovations in Clinical Excellence Evidence-Based Practice Contest Winners I - Sigma Theta Tau International 38th Biennial Convention November 12-13, 2005, Indianapolis, IN

Friday, November 11, 2005

Friday November 11, 2005
Regarding Lactate level

It is worth to continue to emphasize to house staff that:

1. if feasible 'arterial' lactate is preferable to venous lactate as it get influenced with time and pressure of tourniquet.


2. Lactate level is under-utilized blood workup in sepsis patients. Its not a perfect analogy but as CPK and MB is to chest pain, WBC (Leucocytosis) and lactate level is to sepsis. (We are still in search of troponin of sepsis!).

3. Time matters exactly same in septic attack as in heart attack and brain attack. Lactate level (even venous) can help tremendously in identifying this attack early when hemodynamic is still relatively stable.


See
Rivers early goal directed therapy's algorithm. - (NEJM) where lactate level of 4 has been used as cutoff point to start algorithm.

References: Click on link to get abstract/article:
1.
Changes in venous blood lactate, venous blood gases, and somatosensory evoked potentials after tourniquet application - Anesthesiology. 1988 Nov;69(5):677-82
2.
Early Goal-directed Therapy in the Treatment of Severe Sepsis and Septic Shock - November 2001, NEJM

Thursday, November 10, 2005

isp

Thursday November 10, 2005
ICU satellite pharmacy


Although there is no study done but anecdotal reports shows that decentralization of pharmacy with ICU having its own satellite pharmacy (ideally having its own critical care pharmacist) decrease medication errors and probably is more cost-effective for hospital due to focused expertise and increase communication with nurses/physicians. Similar has been recommended as "desirable services" in Position paper on critical care pharmacy services from Society of Critical Care Medicine and American College of Clinical Pharmacy's Task Force on Critical Care Pharmacy Services.

References: Click on link to get abstract/article:
1.
Declaring victory in the war against drug errors - Sept. 2005, Today’s Hospitalist.
2.
Position paper on critical care pharmacy services from Society of Critical Care Medicine and American College of Clinical Pharmacy Task Force on Critical Care Pharmacy Services. - Critical Care Medicine. 28(11):3746-3750, November 2000

Wednesday, November 09, 2005

Wednesday November 9, 2005
Donut Magnets


If encountered with a situation where patient's AICD (Automatic Implantable Cardioverter Defibrillator) continue to fire inappropriately causing hemodynamic issues or mostly when during or after the 'code', AICD needs to be deactivated - ask for "Donut Magnets" ONLY as other regular magnets may not work. Put donut magnet directly over AICD. Once AICD deactivated you may hear a long beep(s) but important thing is to keep magnet there and tape it firmly till seen by cardiology. Its important, if patient fails cardio-pulmonary resuscitation, to deactivate AICD, confirm underlying asystole/rhythm before calling off the code.

See sample of ems driven
AICD deactivation protocol - from scdhec.gov

Tuesday, November 08, 2005

Tuesday November 8, 2005
Troponin-I or Troponin-T ?

As picture is getting more clear about Troponins, it appears that Troponin-I does not get affected with renal insufficiency/failure. While 'sustained' elevated Troponin-T reflects poor cardiac baseline and predicts poor overall cardiac mortality. If Troponin-I is not available in your hospital, a spike (bell curve) or continuously rising Troponin-T may be an indicator of acute coronary event but low level sustained value may just reflect baseline cardiac decompensation.


Refrences: click on link to get article/abstract
1.
Clinical Association between Renal Insufficiency and Positive Troponin I in Patients with Acute Coronary Syndrome - Cardiology 2004;102:215-219
2.
Cardiac troponin-I before and after renal dialysis - Clinical Nephrology, Vol. 54 - No. 3/200
3.
Troponin is related to left ventricular mass and predicts all-cause and cardiovascular mortality in hemodialysis patients. - Am J Kidney Dis. 2002 Jul;40(1):68-75.

Monday, November 07, 2005

etstsl

Monday November 7, 2005
ESCAPE Trial - setback to swan lovers?


Debate on pulmonary artery catheter is non-ending in critical care culture. Recently JAMA has published 2 studies which may make swan-believers unhappy.

1. ESCAPE Trial (Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness): which showed that use of the PAC did not significantly affect the primary end point of days alive and out of the hospital during the first 6 months. Also, In-hospital adverse events were more common among patients in the PAC group.

2. Impact of the Pulmonary Artery Catheter in Critically Ill Patients - Meta-analysis of 13 Randomized Clinical Trials which showed that in critically ill patients, use of the PAC neither increased overall mortality or days in hospital nor conferred benefit.

Now we have to wait for results of FACTT study from ARDSnet evaluating the use of a Pulmonary Artery Catheter versus Central Venous Catheter (CVP) in patients with Acute Lung Injury and ARDS.

Refrences: click on link to get article/abstract
1.
The ESCAPE Trial JAMA. 2005;294:1625-1633
2.
Impact of the Pulmonary Artery Catheter in Critically Ill Patients -JAMA. 2005;294:1664-1670.
3.
FACTT trial - ARDSNet

Sunday, November 06, 2005

Sunday November 6, 2005
Is low HDL marker for sepsis mortality?

Although it is a small prospective, observational cohort study of only 63 patients (National Taiwan University Hospital) but interesting to note the conclusion that:

A low HDL cholesterol level (cutoff value at 20 mg/dL) on day 1 of severe sepsis was significantly associated with an increase 30 day mortality, increase ICU stay and hospital acquired infection. (All other septic parameters adjusted).

Another interesting finding at continuation of work back to bench while blood samples were obtained and serum was immediately stored at -80°C until analysis : ...HDL can attenuate LPS (Lipopolysaccharide)-induced TNF-รก production only if added concomitantly with, but not after, LPS exposure.

Refrences: click on link to get article/abstract
1.
Low serum level of high-density lipoprotein cholesterol is a poor prognostic factor for severe sepsis - Critical Care Medicine: Volume 33(8) August 2005 pp 1688-1693

Saturday, November 05, 2005

Saturday November 5, 2005
Pneumocystis Jiroveci (PCP) - previously P. carinii


Patients with Pneumocystis jiroveci (PCP) usually detriorate in first 2 -3 days of treatment with worsening of A-a gradient (Alveolar-arterial gradient of oxygen) and this should not be presumed as treatment failure. If patient continue to show same trend by 5-7 days than treatment failure should be considered. Initial worsening is due to inflammation as organisms get killed and this is one of the reason to administer steroid at the initiation of PCP treatment.

Nomenclature has been changed as DNA analysis by PCR (polymerase chain reaction) showed that sequences from P. jiroveci (human-derived) differ by 5% from P. carinii (rat-derived). But acronym PCP has been retained for Pneumocystis pneumonia. Jiroveci (pronounced "yee row vet zee") has been named in honor of the Czech parasitologist Otto Jirovec, who is credited with describing the microbe in humans in 1999.


Refrences: click on link to get article/abstract
1.
A New Name (Pneumocystis jiroveci) for Pneumocystis from Humans - cdc.gov
2.
Pneumocystis pneumonia in humans is caused by P jiroveci not P carinii - Thorax 2004;59:83-84 (letter to editor)

Friday, November 04, 2005

Friday November 4, 2005
Prone positioning target - O2 or PCO2 ?


Literature on prone postioning in ARDS is not encouraging4 but as Dr. Alain F. Broccard showed optimism by saying: "Are We Looking at a Half-Empty or Half-Full Glass?" (ref. 2).

Dr. Gattinoni's 2001 NEJM article (ref. 3) failed to show any benefit on survival despite improved oxygenation but 2 years later his article in Critical Care Medicine Journal (Ref. 1) found that ARDS patients who respond to prone positioning with reduction of their Paco2 show an increased survival at 28 days. Improved efficiency of alveolar ventilation (decreased physiologic deadspace ratio) has been concluded as an important marker of patients who will survive acute respiratory failure.

So the Question is: In prone positioning should we target improve oxygenation or decreasing Paco2 ????

Refrences: click on link to get article/abstract
1.
Decrease in Paco2 with prone position is predictive of improved outcome in acute respiratory distress syndrome - Crit Care Med 31(12):2727-2733, 2003
2.
Prone Position in ARDS Are We Looking at a Half-Empty or Half-Full Glass? - (Chest. 2003;123:1334-1336.)
3. .
Effect of Prone Positioning on the Survival of Patients with Acute Respiratory Failure - NEJM, Aug. 2001- Volume 345:568-573
4.
Effects of Systematic Prone Positioning in Hypoxemic Acute Respiratory Failure - JAMA - Vol. 292 No. 19, November 17, 2004

Thursday, November 03, 2005

Thursday November 3, 2005
Regarding Valproic acid (VPA; Depakote) overdose

Few important points good to know in Valproate toxicity:

1. Hyperammonemia could occur without liver function test abnormalities.

2. Cerebral edema may become apparent even upto 4th day post ingestion and is not dose related so close monitoring is required despite level shows normalization.

3. Mechanism of action is unknow but in some patients Naloxone shows improvement in mental status so it should be considered.

4. There is no antidote available but administration of L-carnitine (50 mg/kg/day) in patients with hyperammonemia and neurological symptoms may help.

5. Hemodyalysis (Charcoal hemoperfusion is preferred if available) works only if level is above 100 ug/ml as protein binding sites become saturated and free drug is available for hemodyalizing.

6. Free valproate level should be send in patients with unexplained altered cognition, but normal serum (protein bound) levels.

Refrences: click on link to get article/abstract
1.
Toxicity, Valproate - emedicine.com
2.
Valproic acid toxicity: overview and management. - J Toxicol Clin Toxicol. 2002;40(6):789-801
3
Neurotoxicity Associated With Free Valproic Acid - Am J Psychiatry 162:810, April 2005
4. Delayed valproic acid toxicity: A retrospective case series - Ann Emerg Med. 2002 Jun;39(6):616-21

Wednesday, November 02, 2005

Wednesday November 2, 2005
Regarding Needle Thoracostomy

Needle thoracostomy continue to be one of the life saving procedures in ICUs for tension pneumothorax. But recent literature and anecdotal reports suggest that needle thoracostomy should be perform only in situations where severe hemodynamic compromise is imminent or diagnosis of pneumothorax is very clear. It is not a benign procedure as thought and should not be taken lightly. Blind needle thoracostomy carries good risk of lung laceration and air embolism through such a laceration is a real concern. If possible, its better to wait for radiological confirmation and perform chest tube placement in more controlled enviroment.

Another point raised in recent literature is regarding length of the needle. Standard 5 cm long needle has been found to fail 25% of the procedures. (14-16 G IV cannula is preferred). If thick chest wall presumed, 6 cm long needle has been recommended.

Refrences: click on link to get article/abstract
1.
Needle Thoracostomy - Archive of debate at trauma.org
2.
image of procedure site - Deptt. of Anesth. & inten. care, Chinese Univ. of Hong Kong
3
Needle Thoracostomy: Implications of Computed Tomography Chest Wall Thickness - Acad Emerg Med Volume 11, Number 2 211-213
4.
Needle Thoracostomy in Trauma Patients: What Catheter Length Is Adequate? - Acad Emerg Med Volume 10, Number 5 495.

Tuesday, November 01, 2005

Tuesday November 1, 2005
Immune reconstitution inflammatory syndrome


Immune reconstitution inflammatory syndrome (IRIS) is relatively a newly discovered phenomenon encountered by those intensivists who take care of HIV patients. Some individuals who initiate "HAART" (Highly Active Antiretroviral Therapy) regimen develop new or paradoxical worsening of opprtunistic infections or malignancies despite improvements in surrogate markers of HIV infection. Reportedly it develops in patients with profound immunosuppression (usually below CD4 count of 100). Classic example is a study which showed that 30% of HIV patients coinfected with Cryptococcus neoformans who initiated HAARTdeveloped IRIS with higher cerebrospinal fluid opening pressures, glucose levels, and white blood cell counts.

Refrences: click on link to get article/abstract
1.
The role of immune reconstitution inflammatory syndrome in AIDS-related Cryptococcus neoformans disease in the era of highly active antiretroviral therapy. - Clin Infect Dis. 2005 Apr 1;40(7):1049-52.
2.
Recent IRIS related articles/literature - hivandhepatitis.com
3.
Immune Reconstitution Inflammatory Syndrome Associated With Kaposi's Sarcoma - Journal of Clinical Oncology, Vol 23, No 22 (August 1), 2005: pp. 5224-5228
4.
Immune Reconstitution Inflammatory Syndrome Associated With HIV and Leprosy - Arch Dermatol. 2004;140:997-1000.