Icuroom pearls - December 2006

2006-12-31T18:50:00.000-08:00

Sunday December 31, 2006
CURB-65 Score

Lim and colleagues have designed a score called CURB-65 to rate mortality in community acquired pneumonia (CAP) - based on information available at initial hospital assessment. Give one point each for following values

C = Confusion
U = Urea (BUN) if more than 20 mg/dl (7 mmol/l)
R = Respiratory rate if more than / = 30/min,
B = BP if SBP less than 90 or DBP less than/= 60,
65 = If age more than / = 65 years

With score 0 expected mortality is 0.7%,
With score 1 expected mortality is 3.2%,
With score 2 expected mortality is 13%,
With score 3 expected mortality is 17%,
With score 4 expected mortality is 41.5% and
With score 5 expected mortality is 57%

Reference:

1.Defining community acquired pneumonia severity on presentation to hospital: an international derivation and validation study - W S Lim, M M van der Eerden, R Laing, W G Boersma, N Karalus, G I Town, S A Lewis and J T Macfarlane - Thorax 2003;58:377-382

2006-12-30T08:57:00.000-08:00

Saturday December 30, 2006
IV Nimodipine

For intensivists who work in "neuro" units, it may be of interest to know that there are reports of using Nimodipine intravenously (IV) in patients who cannot tolerate oral route. But FDA has a strong warning again giving it intravenously or parenterally. It can cause serious adverse events, including death. Nimodipine is a calcium-channel blocker, which lowers blood pressure; and when given intravenously it may cause cardiovascular collapse. Ensure that nimodipine never administered intravenously as it is not safe.

Reference: click to read warning

Alert for Healthcare Professionals Nimodipine (marketed as Nimotop) - pdf file - fda.gov

2006-12-29T13:23:00.000-08:00

Friday December 29, 2006
Four generations of Quinolones

The classification of the fluoroquinolones on the basis of generations (imitating from cephalosporins) is not officially standardized, but it is now commonly use to classify them by their spectrum of action.

1st generation - Gram negative coverage but not pseudomonas (example: Nalidixic acid)

2nd generation - Gram negative coverage with pseudomonas and some gram postive coverage including s.aureus but not strep pneumoniae. (example: Ciprofloxacin, Ofloxacin, Norfloxacin)

3rd generation - Gram negative coverage with pseudomonas. More gram postive coverage including penicillin sensitive and resistant s. pneumoniae. (example: Levofloxacin, Sparfloxacin, Gatifloxacin (tequin), Moxifloxacin (avalox)). Avalox has been said to be the most effective in this generation.

4th generation - Same as 3rd generation but with anaerobic coverage (example: Trovafloxacin (Trovan) ).

Read comprehensive review on Quinolones (Source: Am Fam Physician 2002;65:455-64, authors: CATHERINE M. OLIPHANT, PHARM.D., University of Wyoming School of Pharmacy and GARY M. GREEN, M.D., Kaiser Permanente, California)

2006-12-28T04:33:00.000-08:00

Thursday December 28, 2006
Heparin Induced HyperKalemia

Hyperkalemia from Heparin is a well know phenomenon and has been detected particularly on geriatric, renal insufficient and diabetic patients. Hyperkalemia can be anywhere from .3 to 1.7 mEq/Litre. It usually occurs around on day 3 with SQ heparin (as for DVT prophylaxis) but can occur early with IV heparin 1,2,3,4. Hyperkalemia has been reported with low- molecular weight heparins too but risk is low 5, 6, 7.

Mechanism of action: Heparin induce hypoaldosteronism and can subsequently lead to hyperkalemia 6.

Treatment: Best thing is to discontinue the culprit but if heparin is absolutely required, fludrocortisone (.1 mg/day) has been reported to be effective in heparin-induced hyperkalemia 8.

References: Click to get abstracts/articles

1. Case report - Heparin-induced hyperkalemia after cardiac surgery - Ann Thorac Surg 2002;74:1698-1700
2. Heparin-induced hyperkalemia -The Annals of Pharmacotherapy: Vol. 24, No. 3, pp. 244-246.
3. Heparin Induced HyperKalemia - Endocrine Abstracts (2002) 4 P26
4. Heparin-Induced Hyperkalemia Confirmed by Drug Rechallenge. American Journal of Physical Medicine & Rehabilitation. 79(1):93-96, January/February 2000.
5. Early onset of hyperkalemia in patients treated with low molecular weight heparin: a prospective study - Pharmacoepidemiol Drug Saf.2004 May;13(5):299-302.
6. Effect of Low-Molecular-Weight Heparin on Potassium Homeostasis - Pathophysiology of Haemostasis and Thrombosis 2002;32:107-110
7. Low Molecular Weight Heparins Can Lead To Hyperkalaemia The Internet Journal of Geriatrics and Gerontology . 2005. Volume 2 Number 2.
8. Fludrocortisone for the treatment of heparin-induced hyperkalemia - The Annals of Pharmacotherapy: Vol. 34, No. 5, pp. 606-610

2006-12-27T08:24:00.000-08:00

Wednesday December 27, 2006
IV insulin dose

As ICUs are moving more and more towards protocol based orders, insulin drip protocol remains one of the most sought protocol. There is no proven formula available for the dose of insulin drip but one 'rule of thumb' available is as follows:

(Current Blood Glucose - 60) x multiplier = number of units of insulin/hour

Multiplier could range anywhere from .01 to .09 depending on level of glucose control required. Practically, start multiplier from .01 or .02 and continue to escalate till desired tight control achieved.

Like patient with blood sugar of 359 may start with as low as (359-60) x .01 = 3 units/hour but depending on further blood glucose level may require upto (359-60) x .09 = 27 units/hour of insulin.

The best precise article we found with all insulin related protocols is Hospital management of diabetes: Beyond the sliding scale written by Dr. Etie Moghissi, Co-chair, American College of Endocrinology Task Force on Inpatient Diabetes and Metabolic Control. ( Reference: CLEVELAND CLINIC JOURNAL OF MEDICINE VOLUME 71 • NUMBER 10 OCTOBER 2004. Page 801).

2006-12-26T20:59:00.000-08:00

Tuesday December 26, 2006
Diagnosis of VAP - BAL vs endotracheal aspiration

Study published in this week's issue of The New England Journal of Medicine should be of interest for physicians getting burned with ventilator-associated pneumonia. Study was done to look into the optimal diagnostic approach in suspected ventilator-associated pneumonia - bronchoalveolar lavage with quantitative culture of the bronchoalveolar lavage vs endotracheal aspiration with nonquantitative culture of the aspirate.

Out of 740 patients there was no significant difference in the primary outcome (28-day mortality rate) between the two groups. Also there was no difference in the length of stay in the ICU or hospital. There was no difference in the use of targeted or no use of antibiotics.

Note: After the diagnostic tests had been completed, empirical antibiotic therapy was initiated in all patients until culture results were available. Patients randomly assigned to receive either IV meropenem (1 gram every 8 h) and IV ciprofloxacin (400 mg every 12 hours) or meropenem alone. With positive culture, antibiotic has been adjusted.

Clinical significance of the study: After start of empirical antibiotics in suspected ventilator-associated pneumonia, mode of diagnostic approach remains secondary. Performing bronchoalveolar lavage with quantitative culture does not provide any major benefit and may be avoided as routine practice to provide cost saving measure. Simple endotracheal aspiration provides the the same clinical outcome.

Reference: click to get abstract

A Randomized Trial of Diagnostic Techniques for Ventilator-Associated Pneumonia - The New England Journal of Medicine, Volume 355:2619-2630, Dec. 21, 2006

2006-12-25T01:58:00.000-08:00

Merry Christmas

What do you call an intensivist working on Christmas day?

Santa-in-the-box

2006-12-24T09:20:00.000-08:00

Sunday December 24, 2006
Post fellowship shock syndrome

Post fellowship shock syndrome is a kind of culture shock for young graduates when they transit from big tertiary care academic centers to regular community based medical practice. Transit from high tech., literature oriented, academic based and superior nursing quality to business oriented, "thats how we do things here" practice, no house staff support, no billing and business experience and wide spectrum of nursing quality - put unprepared young graduates into mental and cultural shock and may leave them frustrated with present situation. And sometime in changing jobs they find themselves jumping from firepan to fire. It is important to prepare graduating residents and fellows for business and billing practice of medicine.

(Post fellowship shock syndrome is a term invented by editors of this website)

2006-12-22T21:33:00.000-08:00

Saturday December 23, 2006
Iodide in Thyroid Storm

Q; How long should you wait to administer iodide after giving antithyroid medication in the management of thyroid storm ?

A; Atleast one hour.

Oral or rectal iodide compounds block release of thyroid hormones after starting antithyroid drug therapy. But if given early in management (before antithyroid medication become effective) it can get utilize in the synthesis of new thyroid hormone.

Read nicely written review on Thyroid Storm (and Myxedema coma) by Nikolaos Stathatos, MD, and Leonard Wartofsky, MD from Washington Hospital Center in Washington, D.C. - ref.: emedmag.com, 02/15/2003 issue.

2006-12-22T03:44:00.000-08:00

Friday December 22, 2006
Ibutalide (Corvert)

Use of Ibutalide has practically became non-existent due to fear of provoking torsades de pointes. It is true that 4% of patients may develop torsades de pointes but still it is a very useful drug to convert atrial flutter or fibrillation of recent onset. It has a very high rate of chemical cardioversion.

Consider a situation where you have "only chemical code" patient who has gone into acute atrial fibrillation with severe hemodynamic instabilty. Amiodarone may not be a perfect choice as a chance of cardioversion with amiodarone is only 5% and overall it is a good drug for rate control instead of cardioversion. Moreover, bolus of amiodarone may dips down blood pressure further. Point is - intensivists need to be aware of this drug as a backup when all other options are exhausted.

The usual dose of ibutilide is 1 mg followed by another dose if the first one is not effective.

2006-12-21T10:08:00.000-08:00

Thursday December 21, 2006
Purple urine bag syndrome

The purple urine bag syndrome is characterized by the purple discoloration of the urine, of collecting bag, and of draining tube. It is a rare condition associated with chronic catheterization of urinary tract. It is also called The King's Royal Urine as England's "Mad" King George III in early 19th century reported to have bouts of bluish/purplish color urine. Exact etiology is unknown and many explanations have been described. It is said to be a triad of

constipation,
alkaline urine and
bacteria in the urinary tract that produce the enzyme sulphatase/phosphatase like Pseudomonas aeruginosa, Proteus mirabilis, Morganella morganii and E. coli.

It has been said that constipation lead to bacterial overgrowth in colon and in combination with UTI produce this syndrome.

Purple color is produced by combination of red and blue color. indirubin (red) is produced in this process and get dissolved in the plastic of the drainage bag, ostomy pouch, or urinary catheter, and indigo crystals (blue) in the urine coat the bag or tube, combining to form the purple color.

The longer the drainage system is used, the deeper the purple color becomes. A strong odor often is associated with PUBS which gets stronger as temperature in the room rises ! Due to unknown reason, it is more common in female patients.

Overall it is a benign condition. Treatment includes good hygiene, changing catheters as needed, avoiding constipation and if needed antibiotics.

2006-12-20T11:25:00.000-08:00

Wednesday December 20, 2006

Q; What is the best time to draw Vancomycin level in chronic intermittent haemodialysis patients ?

A; Vancomycin (random or trough) level in patients undergoing chronic intermittent haemodialysis should be drawn ideally before the haemodialysis session. Or atleast 6 hours after the dialysis session.

The vancomycin plasma concentration decreases dramatically during the dialysis session and then gradually increases when the session is stopped for 4–6 hours. Drawing level during dialysis session or too soon after the session may give falsely low trough level.

Related previous pearls:

What should be the target Vancomycin level ?

Vancomycin dosing in CRRT

Vancomycin-induced Stevens-Johnson syndrome

2006-12-19T16:14:00.000-08:00

Tuesday December 19, 2006
Something to share !

Today we will take a little break to share this important statement:

"As you learn to become a doctor, there is a frequent sense of surprise, a feeling that you are not entitled to the kind of intrusion you are allowed into patients' lives. Without arguing, they permit you to examine them; it is impossible to imagine, when you do your very first physical exam, that someday you will walk in calmly and tell a man your grandfather's age to undress, and then examine him without thinking about it twice. You get used to it all, but every so often you find yourself marveling at the access you are allowed, at the way you are learning from their bodies, the stories, the lives and deaths of perfect strangers. They give up their privacy in exchange for some hope - sometimes strong, sometimes faint - of the alleviation of pain, the curing of disease. And gradually, with medical training, that feeling of amazement, that feeling that you are not entitled, scars over. You begin to identify more thoroughly with the medical profession - of course you are entitled to see everything and know everything; you're a doctor, aren't you? And as you accept this as your right, you move further from your patients, even as you penetrate more meticulously and more confidently into their lives." - Perri Klass, M.D.

Read more about Dr. Klass here - source nih.gov

2006-12-18T15:12:00.000-08:00

Monday December 18, 2006
Bedseide procedure tip ! - application of chlorhexidine

While preping skin for bedside procedures with chlorhexidine only one round of the application is enough. As we all are use to apply three applications of Betadine (povidone-iodine), there is a tendency to do the same with chlorhexidine. Also as chlorhexidine is colorless, in pursuit of safety, we tend to apply extra amount.

Excessive use of chlorhexidine may cause a severe dermatitis reaction 1-3 . One application of chlorhexidine is enough and more safe.

Related previous pearl: Betdadine or Chlorhexidin ?

References : Click to get article/abstract
1. Allergic contact dermatitis from chlorhexidine. - Dermatitis. 2004 Mar;15(1):45-7.
2. Contact dermatitis to chlorhexidine - Contact Dermatitis, Volume 8 Issue 2 Page 81 - April 1982
3. IgE-mediated anaphylaxis from chlorhexidine: diagnostic possibilities - Contact DermatitisVolume 55 Issue 5 Page 301 - November 2006

2006-12-17T14:35:00.000-08:00

Sunday December 17, 2006

Abdominal Perfusion Pressure

Intra-abdominal compartment syndrome is an under-diagnosed entity particularly in medical ICUs (in comparison to surgical or trauma ICUs) but with massive fluid resuscitation as part of critical care management, intensivists need to be constantly cautious of this complication.

Intra-abdominal Hypertension: is defined as sustained or repeated bladder pressure more than/= 12 cm H2O

Abdominal compartment syndrome: is defined as sustained or repeated pressure more than/= 20 cm H2O.Bladder pressure is not the accurate method of diagnosing IAH. Dr. Cheatham has proposed APP (Abdominal Perfusion Pressure) as better indicator with formula taken from another compatment syndome - cerebral perfusion pressure, (CPP= MAP-ICP)

APP = MAP- IAP

where MAP is mean arterial pressure and IAP is intra-abdominal pressure.

Intra-abdominal Hypertension is defined as sustained or repeated APP less than or = 60

Related web site: The World Society of the Abdominal Compartment Syndrome

Reference : Click to get article/abstract

1. Abdominal Perfusion Pressure: A Superior Parameter in the Assessment of Intra-abdominal Hypertension Journal of Trauma-Injury Infection & Critical Care. 49(4):621-627, October 2000.

2006-12-16T10:21:00.000-08:00

Saturday December 16, 2006

Q: One side effect you need to be aware of Daptomycin (Cubicin) ?

A: Daptomycin induced rhabdomyolysis and consequently acute renal failure.

Daptomycin is a bactericidal antibiotic against most Gram-positive organisms including methicillin-resistant Staph. aureus (MRSA) and vancomycin-resistant enterococci (VRE). Initially, it was reported that if given as once a day instead of divided dose it prevents clinical rhabdomyolysis but recent reports describe rhabdomyolysis even with once a day dose.

Close monitoring of CPK and symptoms of myopathy is recommended in all patients started on daptomycin.

Read case report and discussion: Rhabdomyolysis and acute renal failure in a patient treated with daptomycin (Journal of Antimicrobial Chemotherapy)

Further reading : Click to get article/abstract

Severe myopathy and possible hepatotoxicity related to daptomycin - Journal of Antimicrobial Chemotherapy 2005 55(4):599-600

2006-12-15T18:45:00.000-08:00

Friday December 15, 2006
IPV - adjuvant therapy in COPD exacerbations ?

A study of 33 patients, published from france last year on acute exacerbation of COPD. Inclusion and exclusion criteria were established (see reference). Patients were randomly assigned to receive either standard treatment (control group) or standard treatment plus Intrapulmonary percussive ventilation (IPV group).

The IPV group underwent two daily sessions of 30 minutes performed by a chest physiotherapist through a full face mask. Thirty minutes of IPV led to a significant decrease in respiratory rate, an increase in PaO2 and a decrease in PaCO2. Exacerbation worsened in 6 out of 17 patients in the control group versus 0 out of 16 in the IPV group. Therapy was tagged successful when both worsening of the exacerbation and a decrease in pH to under 7.35, which would have required non-invasive ventilation, were avoided. Also, the hospital stay was significantly shorter in the IPV group.

IPV is essentially a very effective technique to assist patients to clear retained endobronchial secretions and the resolution of diffuse patchy atelectasis.

Please see full manual of IPV therapy from Dr. Bird's website here.

Reference : Click to get article/abstract

Intrapulmonary percussive ventilation in acute exacerbations of COPD patients with mild respiratory acidosis: a randomized controlled trial - Crit Care. 2005; 9(4): R382–R389

2006-12-14T09:57:00.000-08:00

Thursday December 14, 2006
Phlebotomy in ICUs

Q: How much blood a patient on average loose via phlebotomy per week of ICU stay ?

Answer: 500 cc (about 1 unit of whole blood) per week

Phlebotomy (blood draws) is the major or probably the # 1 cause of anemia in ICUs. In very anemic patients, if blood workup is necessary it would be advisible to use pediatric tubes except for blood cultures where 10-20 cc of blood draw is required. As it was given as pearl earlier on this site that with each 100 ml of blood draws, Hb drop by 0.7 g/dL. Best practice would be to avoid unnecessary blood workup.

See related commentary: Transfusion Practice in the ICU, When Will We Apply the Evidence?, Andrew F. Shorr, MD, MPH and William L. Jackson, MD, Walter Reed Army Medical Center, Washington, DC (Chest. 2005;127:702-705)

Related previous Pearl: ICU anemia score

2006-12-13T09:38:00.000-08:00

Wednesday December 13, 2006
Back to basic !

The reentrant circuits in Atrial Fibrillation usually arise from.......... (choose one)

A) Right Atrium

B) Left Atrium

Answer: Left Atrium.

As SA Node lies in right atrium, there is a general misconception that atrial fibrillation arise in right atrium but usually the abnormal foci is in left atrium near the entrance of pulmonary veins. In Maze procedure, the ablation path surrounds the pumonary veins (click on images to see their web link).

2006-12-12T08:22:00.000-08:00

Tuesday December 12, 2006
Noninvasive ventilation to prevent re-intubation !

One study published last year looking into the efficacy of application of noninvasive ventilation in high risk patients to prevent reintubation.

97 consecutive patients requiring mechanical ventilation for more than 48 hours and considered at risk of developing postextubation respiratory failure due to hypercapnia, CHF, ineffective cough, excessive secretions, more than one failure of a weaning trial, more than one comorbid condition etc. were included.

The patients were randomized to receive either noninvasive ventilation (NIV) for about 8 hrs a day in the first 48 hrs or Standard medical treatment (SMT).

NIV group had a lower rate of reintubation 4 of 48 (8.3%) vs. 12 of 49 (24.5%). Also, the use of NIV resulted in a reduction of risk of ICU mortality, mediated by the reduction in the need for reintubation.

Related previous pearl: What is the re-intubation rate in your ICU?

References: Click to get abstract/article

1. Noninvasive ventilation to prevent respiratory failure after extubation in high-risk patients - Critical Care Medicine. 33(11):2465-2470, November 2005.

2006-12-10T19:15:00.000-08:00

Monday December 11, 2006
Expected drop in Hb after cardiac angiogram

Patients going for cardiac angiogram frequently requires blood transfusions either pre or post procedure. Particularly, patient who determined to need emergent CABG should have enough backup transfusion avaiable.

To keep yourself prepared, it would be nice to know that coronary angiography on average drop 1.8 g/dL of Hb per procedure.

References: Click to get abstract/article

1. Blood loss from coronary angiography increases transfusion requirements for coronary artery bypass graft surgery - The Journal of Cardiothoracic and Vascular Anesthesia , volume 14, issue 2, Pages 177-181 (April 2000)

2006-12-10T00:22:00.000-08:00

Sunday December 10, 2006
Hemodialysis in Salicylate overdose with normal level

Hemodialysis is recommended in salicylate overdose patients with a level at or above 100 mg/dL (cut it to half if history suggest chronic ingestion). But if there is any sign of neurological manifestation, dialysis is indicated despite normal level.
Salicylate cause "neuroglycopenia" (lower CNS glucose level) despite normal serum glucose. As patient gets more and more acidotic, salicylate enters CNS and by direct effect cause neuroglycopenia. 7 indications of Hemodialysis in Salicylate poisoning

1. Mental status change
2. Pulmonary edema
3. Cerebral edema
4. Associated or with renal failure
5. Level at or above 100 mg/dL(half if chronic ingestion)
6. If fluid overload prevents alkalinization
7. Patient continue to deteriorate clinically

References: Click to get abstract/article

1. Toxicity, Salicylate - emedicine.com
2.An evidence based flowchart to guide the management of acute salicylate (aspirin) overdose -Emerg Med J 2002; 19:206-209
3. Salicylic acid - intox.org

2006-12-08T21:41:00.000-08:00

Saturday December 09, 2006
PICC or CVC ?

Lately, there has been a trend particularly in community hospital settings to use PICCs (Peripherally inserted central venous catheters) more and more than CVCs (central venous catheters). There is no head to head trial available to compare them particularly in ICUs but it appears that PICC provides no added benefit or actually may be less efficacious and even harmful in comparison to CVC. Major disadvantages
more vulnerable to thrombosis
more vulnerable to dislodgment
hard in drawing blood specimens
clogged more easily
has only 2 ports
can't measure CVP (or need extra measures) * see related pearl below
not good for fluid resuscitation because of its longer length.
in patients with impending renal failure, it may not respect the preservation of upper-extremity veins which is needed for fistula or graft implantation.

Also, Dr. Safdar and Dr. Maki last year reported in chest that PICCs used in high-risk hospitalized patients are associated with a rate of catheter-related BSI similar to conventional CVCs placed in the internal jugular or subclavian veins.

The advantages of PICC are: they can be easily put by non-physician 'line team' and could be a choice of intravenous access in very obese patients.

Related previous Pearl: Can we measure CVP via PICCs ?

Reference: click to get abstract/article

1. Risk of Catheter-Related Bloodstream Infection With Peripherally Inserted Central Venous Catheters Used in Hospitalized Patients - Chest. 2005;128:489-495.

2006-12-08T09:57:00.000-08:00

Friday December 08, 2006

Q: Which common blood test in ICU may be misleading if you use hetastarch (hespan) as volume resuscitation?

A; Amylase

Hetastrach gets attached to amylase and reduce its clearance by kidney and may cause significant elevated amylase level for about one week after infusion. It is a benign effect but may get misdiagnosed as pancreatitis. Differential can be confirmed by lipase level which remains normal.

2006-12-07T11:49:00.000-08:00

Thursday December 07, 2006
Helium embolus

Intra Aortic Balloon Pump (IABP) Counterpulsation utilizes helium gas to inflate its balloon. As Helium is a low density as well as an inert gas, in case of balloon rupture it is easily absorbed into the bloodstream.

But fairly well numbered incidents of "Helium emboli" after balloon rupture have been described in literature. Major clinical sign of helium embolus is neurological deficit associated with other findings of balloon rupture as blood in the tubing. Treatment is hyperbaric oxygen.

Reference: click to get abstract / article

Arterial helium embolism from a ruptured intraaortic balloon - Ann Thorac Surg. 1988 Dec;46(6):690-2.

2006-12-06T18:45:00.000-08:00

Wednesday December 06, 2006

Q: Which procedure can be use both as diagnostic as well as therapeutic in acute colonic pseudo-obstruction (Ogilvie syndrome) ?

A; Gastrografin enema

Gastrografin is a contrast medium which is water-soluble but has a high osmolarity and so causes a fluid shift into the colon and subsequently increases colonic motility. A Gastrografin enema may be both diagnostic and therapeutic for this disorder.

Medical treatment of acute colonic pseudo-obstruction (ogilvie syndrome) is 2 mg IV Neostigmine but if diagnosis is suspected on KUB and further workup is underway Gastrografin enema is a good choice. It may relieve pseudo-obstrution without the need of Neostigmine.

Tuesday December 05, 2006
Changing Endotracheal tube (ETT) with Endotracheal Tube Exchangers

Changing Endotracheal tube (ETT) with Endotracheal Tube Exchangers, mostly for large air leaks, seems to be a harmless, easy and relatively a benign procedure but literature speaks against it. Hypoxemia has been reported in 60% during such exchanges and 8% of patients become bradycardic. Proper setup with all backup medications should be available and should be treated as a new intubation procedure.

Read related article: Mishaps With Endotracheal Tube Exchangers In ICU: Two Case Reports And Review Of The Literature - The Internet Journal of Anesthesiology. 2001. Volume 5 Number 1.

Monday December 04, 2006

Q; 65 year old female admitted to ICU 9 days ago with small bowel obstruction. Pt. is now stable and actually is about to get transferred out of unit. Patient suddenly start complaining of choking sensation with two hands on neck. Monitor shows oxygen desaturation. Patient intubated emergently. No laryngeal or vocal edema seen on laryngoscope but vocal cord paralysis noted.

A; Nasogastric tube syndrome

Nasogastric tube syndrome was described about 25 years ago by Sofferman and coll. It is a life-threatening complication of an indwelling (more than a week) nasogastric tube. The syndrome may present as complete vocal cord abductor paralysis. The syndrome is thought to result from perforation of the NG tube-induced esophageal ulcer and infection of the posterior cricoid region (postcricoid chondritis) with subsequent dysfunction of vocal cord abduction. Unilateral paralysis of cord is also described. Treatment is protection of airway, removal of NG tube and antibiotics. Some advocates antireflux therapy too. Another variant is described with no esophageal ulcer but possibly because of ischemia of the laryngeal abductor muscle secondary to physical compression of the postcricoid blood vessels by NG tube.

References: Please click to get abstract

1. The nasogastric tube syndrome: two case reports and review of the literature. Head Neck. 2001 Jan;23(1):59-63.
2. A variant form of nasogastric tube syndrome. Intern Med. 2005 Dec;44(12):1286-90.
3. Case Report - Nasogastric Tube Syndrome: The Unilateral Variant - Medical Principles and Practice Vol. 12, No. 1, 2003
4. Sofferman, R.A. and Hubbell, R.N., "Laryngeal Complications of Nasogastric Tubes," ANNALS OTOLOGY, RHINOLOGY, AND LARYNGOLOGY, 90:465-468, 1981.

Sunday December 3, 2006
What if plasma exchange is not available as treatment of TTP

Q: You just diagnosed a patient with thrombotic thrombocytopenic purpura (TTP) but you were informed by the nursing supervisor that plasma exchange with fresh frozen plasma is not available in hospital due to technical reason and it will take time before patient can be transferred to a facility where the said services are available. What would be your alternate plan to bridge that time?

A; High-dose plasma infusion with rate of 25-30 mL/kg per day. When immediate plasma exchange with fresh frozen plasma is not available, simple plasma infusion can be performed until transfer to a higher care facility is available. There is always a substanial risk of fluid overload with such high plasma infusion and you have to weigh risks and benefits of the clinical decision or to watch patient closely while plasma is infusing.

Reference: click to get abstract/article

High-dose plasma infusion versus plasma exchange as early treatment of thrombotic thrombocytopenic purpura/hemolytic-uremic syndrome - Medicine. 82(1):27-38, January 2003.

Saturday December 02, 2006
Room temperature or Iced Saline ?

Critical Care literature is not clear, actually controversial, regarding the suitable temperature of the solution use as injectable to measure cardiac output via thermodilution. Let see what is the major pro & con of iced saline.

Advantage: Iced injectate gives a higher signal/noise ratio and more reliability in the measured cardiac output. Signal-to-noise ratio is an engineering term for the power ratio between a signal (meaningful information) and the background noise.

Disadvantage: Iced injectate may affect heart rate and cardiodynamics 5.Iced solution may not be as cold as we think after it passes through the operator's hand and long port.Overall literature favors room temperature or atleast does not show any major advantage of using iced saline 1-4.

Related: Thermodilution Cardiac Output Measurement Protocol (sample from Univ. of Carolina Hospitals)

References: click to get abstract/article

1. Cardiac output measured by thermal dilution of room temperature injectate. - Evonuk E, Imig CJ, Greenfield W, et al: J Appl Physiol 1961; 16:271-2752.
2. Cardiac output by thermodilution technique. Effect of injectate's volume and temperature on accuracy and reproducibility in the critically Ill patient - Chest, Vol 84, 418-422, 1983
3. Effect of injectate volume and temperature on thermodilution cardiac output determination - Anesthesiology.1986 Jun;64(6):798-801.
4. Iced versus room temperature injectate for assessment of cardiac output, intrathoracic blood volume, and extravascular lung water by single transpulmonary thermodilution - J Crit Care. 2004 Jun;19(2):103-7.
5. The slowing of sinus rhythm during thermodilution cardiac output determination and the effect of altering injectate temperature. Anesthesiology 1985; 63:540-541

2006-12-06T18:43:00.000-08:00

Friday December 01, 2006

Q; ER papers say - patient received Halivan, what is that?

Halivan is a common medical slang for 'combo' of 5 mg Haldol with 2 mg Ativan to 'cool down' agitated or delirious patient. If you add 25 mg or 50 mg of Benadryl - it is called B52 cocktail !