February 2008 Archive of www.icuroom.net

2008-02-29T08:25:00.000-08:00

Friday February 29, 2008

Q; After successful completion of Transjugular Intrahepatic Porto-systemic Shunt (TIPS) for variceal bleeding - hepatic encephalopathy __________ ?

A) tends to get better

B) tends to get worse

C) It has nothing to do with TIPS

Answer is B

Hepatic encephalopathy tends to get worse after successful completion of TIPS as due to shunting, blood flow to the liver is reduced, which might result in increase toxic substances reaching the brain without being metabolized first by the liver. It can be treated medically such as diet, lactulose or by narrowing of the shunt by insertion of a reducing stent.

References: click to get abstract/article

1. Treatment for hepatic encephalopathy: tips from TIPS? - Journal of Hepatology 42 (2005) 626–628

2. Hepatic encephalopathy after TIPS-- retrospective study - Vnitr Lek. 2002 May;48(5):390-5

3. TIPS for Prevention of Recurrent Bleeding in Patients with Cirrhosis: Meta-analysis of Randomized Clinical Trials - Radiology. 1999;212:411-421

2008-02-28T14:10:00.000-08:00

Thursday February 28, 2008
Critical Care Rounds

Critical Care Rounds is now available on line.

Critical Care Rounds is derived from recent Rounds presented at participating hospitals across Canada in association with The Canadian Critical Care Society.

Website is www.criticalcarerounds.ca

Full archive can be found here

Latest topic is Outcomes, Cost, and Caregiver Burden in the Acute Respiratory Distress Syndrome (ARDS)

Previous topics include

Noninvasive Positive Pressure Ventilation in Critically Ill Patients: The Winds of Change?

Early Determination of Prognosis in Traumatic Brain Injury: Beyond the Glasgow Coma Scale

Initial Evaluation and Management of Severe Community-Acquired Pneumonia

2008-02-27T08:47:00.000-08:00

Wednesday February 27, 2008
Ventilation during CPR - dangers of 'over-bagging'

Per new ACLS guidelines, the rescuer should deliver a tidal volume sufficient to produce chest rise (approximately 6 to 7 mL/kg or 500 to 600 mL) over 1 second with 8 to 10 breaths per minute.

The standard ventilation bag used in adult ICUs have capacity of 1600 ml ! and over enthuisatic bagging can lead to further deterioration of cardio-pulmonary status, particulary when ETT is already in place, where all tidal volume gets directly delivered to lungs. It may cause further decrease in cardiac output.

In case of face-mask ventilation, unrealized effect is over gastric inflation leading to regurgitation and aspiration. Moreover, gastric inflation elevate the diaphragm, restrict lung movement and decrease respiratory system compliance.

Sometime its preferable to do one hand bag ventilation rather than two hand ventilation to avoid 'over bagging'. Depending on hand size, grip strength, height and weight tidal volumes delivered by two hands significantly greater than those delivered by one hand.

Reference: click to abstract / article

1. 2005 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care, Part 7.1: Adjuncts for Airway Control and Ventilation - Circulation. 2005;112:IV-51 – IV-57

2. Comparison of tidal volumes obtained by one-handed and two-handed ventilation techniques, American Journal of Critical Care, Vol 2, Issue 6, 467-473

2008-02-26T09:14:00.000-08:00

Tuesday February 26, 2008
Effect of PEEP on the incidence of aspiration in mechanically ventilated patients

See this interesting study to test the effects of PEEP (positive end expiratory pressure) on the leakage of fluid around cuffs of different tracheal tubes, in mechanically ventilated patients and in a benchtop model.

Patients: 40 patients recovering in the intensive care unit distributed in 2 groupswith 2 different types of ETT Hi-Lo tubes and SealGuard tubes (SG group)

Interventions: Following steps applied
Immediately after intubation and cuff inflation with 30 cm H2O, Evans blue was applied onto the cephalic surface of the tracheal tube cuff
A 5-cm H2O positive expiratory pressure was used during the first 5 hrs of stay, and thereafter it was removed
Leakage was also tested in vitro with the same tracheal tubes with incremental level of PEEP
At 1 hr, 5 hrs, and thereafter hourly until 12 hrs, bronchoscopy was used to test the presence of dye on the trachea caudal to the cuff

Results:
At the fifth hour, two patients of the HL group failed the test
One hour after positive expiratory pressure removal, all subjects in group HL exhibited a dyed lower trachea
One patient in group SG presented a leak at the eighth hour, and at the 12th hour 17 had leak
In vitro, the same level of PEEP delayed the passage of dye

Conclusions: Authors concluded that 5 cm H2O positive expiratory pressure was effective in delaying the passage of fluid around the cuffs of tracheal tubes both in vivo and in vitro.

Reference: click to abstract / article

Effect of positive expiratory pressure and type of tracheal cuff on the incidence of aspiration in mechanically ventilated patients in an intensive care unit , Critical Care Medicine. 36(2):409-413, February 2008

2008-02-25T12:23:00.000-08:00

Monday February 25, 2008
Improving delirium in ICU via education !

In a recent study, Fifty ICU nurses from two different hospitals (university medical and community teaching) evaluated an ICU patient for pain, level of sedation and presence of delirium before-and-after an educational intervention. The same patient was concomitantly, but independently, evaluated by a validated judge who acted as the reference standard in all cases. The education consisted of:

two script concordance case scenarios
a slide presentation regarding scale-based delirium assessment, and
two further cases

Results
Nurses clinical recognition of delirium was poor in the before education period as only 24% of nurses reported the presence or absence of delirium and only 16% were correct compared to the judge.
After education, the number of nurses able to evaluate delirium using any scale (12 vs. 82%) and use it correctly (8 vs. 62%) increased significantly
While judge-nurse agreement (Spearman rho) for the presence of delirium was similar between the pre and post education periods

Conclusions: A simple composite educational intervention incorporating script concordance theory improves the capacity for ICU nurses to screen for delirium nearly as well as experts.

Editors' note: Delirium in general is a very common problem; around 20% patients admitted to hospital have delirium. Delirium is commonly occurs in critically ill patient, especially who have other co-morbidities and have prolonged stay in the ICU. The treatment is difficult to provide, although easy to write: treat the underlying cause. Following site has a lot of information about delirium in icu including videos and other links:

www.icudelirium.org

Reference: click to abstract / article

Combined Didactic and Scenario-Based Education Improves the Ability of ICU Staff to Recognize Delirium at the Bedside , Critical Care, 2008 12:R19 ( 21 February 2008) - open access article - pdf file

2008-02-24T12:29:00.000-08:00

Sunday February 24, 2008
Clonidine and Bradycardia !

Clonidine is a alpha adrenergic agonist with sympatholytic activity and has been used for various clinical indications beside blood pressure control including treatment for migraines, menopausal complaints, narcotic and alcohol withdrawal symptoms, spasticity after spinal cord injury, attention-deficit hyperactivity disorder as well as rate control for atrial fibrillation.

Mechanism of action: Symptomatic bradycardia is a side effect of clonidine which many times go ignored. Clonidine's central effect results in decreased sympathetic outflow and enhanced vagal tone, lowering blood pressure and heart rate. This also cause side effects of drowsiness, lethargy and dry mouth. Clonidine acts peripherally within the heart to inhibit norepinephrine release, contributing to further reductions in heart rate.

Risk factors: Patients at higher risk for clonidine-induced bradycardia seem to be those with an already-diseased conduction system, renal failure, high doses of clonidine, concomitant therapy with medications known to cause bradycardia or heart block, (eg, beta-blockers, verapamil, diltiazem, digoxin).

Treatment: For severe, symptomatic bradycardia, atropine can be used. For refractory symptomatic cases, isoproterenol, epinephrine, dopamine, and pacing may be required.

2008-02-23T19:19:00.000-08:00

Saturday February 23, 2008
One good practice !

Beauty of Critical Care lies in details !

To get less erroneous or in other words consistent lab results is to place a policy for procedure for drawing blood samples from indwelling lines.

If using a multi lumen (eg triple lumen catheter) line for blood drawing, one port of the line should be identified and labelled as the blood withdrawal port and used exclusively for blood drawing if possible.

Definitely, blood should not be drawn from TPN infusion and preferably not from pressor infusions to avoid the hypotensive episodes.

Another important and many time forgotten part - if line is flushed with Heparin, it should be documented in medication list (mostly call MAR in USA).

2008-02-22T10:02:00.000-08:00

Friday February 22, 2008
5-point auscultation post intubation

As soon as intubation is performed, it is a good habit to listen for breath sounds, though not reliable but still provide extra confirmation of proper placement particularly when end-tidal carbon dioxide device is not available.

One recommended method is 5-point auscultation post intubation. Listen over
right lateral lung field,
left lateral lung field,
the left axilla,
the right axilla,
Over stomach to make sure no air movement should occur over the stomach.

Reference:

Tracheal intubation - Anaesthesia & Intensive Care Medicine, Volume 8, Issue 9, Pages 347-351

2008-02-21T09:36:00.000-08:00

Thursday February 21, 2008
Noninvasive Ventilation before Intubation of Hypoxic Patients ?

If enough denitrogenation is not provided critically ill patients are predisposed to quick desaturation during intubation. We found this new approach before intubation in hypoxic patients.

Prospective randomized study was performed, with 2 groups, the control (n = 26) and NIV (n = 27). Preoxygenation was performed, before a rapid sequence intubation, for a 3-min period using a nonrebreather bag-valve mask (control group) or pressure support ventilation delivered by an ICU ventilator through a face mask (NIV group) according to the randomization.

The control (n = 26) and NIV (n = 27) groups were similar in terms of age, disease severity, diagnosis at admission, and pulse oxymetry values (SpO2) before preoxygenation.

Results:
At the end of preoxygenation, SpO2 was higher in the NIV group as compared with the control group (98 ± 2 vs. 93 ± 6%,)
During the intubation procedure, the lower SpO2 values were observed in the control group (81 ± 15 vs. 93 ± 8%)
Twelve (46%) patients in the control group and two (7%) in the NIV group had an SpO2 below 80%
Five minutes after intubation, SpO2 values were still better in the NIV group as compared with the control group (98 ± 2 vs. 94 ± 6%)
Regurgitations (n = 3; 6%) and new infiltrates on post-procedure chest X ray (n = 4; 8%) were observed with no significant difference between groups

Conclusion: For the intubation of hypoxemic patients, preoxygenation using NIV is more effective at reducing arterial oxyhemoglobin desaturation than the usual method.

Reference: click to get abstract /article

Noninvasive Ventilation Improves Preoxygenation before Intubation of Hypoxic Patients, American Journal of Respiratory and Critical Care Medicine Vol 174. pp. 171-177, (2006)

2008-02-20T15:11:00.000-08:00

Wednesday February 20, 2008
Minocycline in Acute Ischemic Stroke ?

Minocycline is a second-generation derivative of tetracycline that has been shown to have a beneficial neuroprotective effect in animal models of MS (multiple sclerosis), Parkinson's disease, Huntington's disease, and ALS. Also, here has been evidence of minocycline's ability to improve outcomes in an animal model of stroke.

Proposed mechanism of action: Proposed mechanisms of action in minocycline include its antiinflammatory effect, reduction of microglia activation, matrix metalloproteinase reduction, nitric oxide production, and inhabitation of apoptotic cell death.

Clinical study: This was an open-label clinical trial, although the evaluator was blinded.

Number (n) = 152 patients who suffered acute ischemic strokes

Mean age = 67 years

74 patients were randomized to receive 200 mg per day of minocycline orally for five days with a therapeutic window of six to 24 hours after onset of stroke. 77 patients were randomized to receive placebo in the same time window.

The primary outcome: was the NIH Stroke Scale score 90 days after admission to the study.

Results:
At day 90, NIH Stroke Scale scores were significantly lower for minocycline-treated subjects compared to placebo treated patients
This difference was already statistically significant by day seven and day 30 of the trial

Conclusion: The investigators conclude that patients with acute stroke had significantly better outcome with minocycline treatment compared to placebo.

Reference: click to get abstract /article

1. Minocycline Treatment in Acute Stroke: An Open-Label, Evaluator-Blinded Study. Neurology; 2007; 69 (October 2): 1404-1410

2008-02-19T21:34:00.000-08:00

Tuesday February 19, 2008
Clinical Institute Withdrawal Assessment for Alcohol—Revised (CIWA-Ar)

The most objective tool to assess the severity of alcohol withdrawal is the Clinical Institute Withdrawal Assessment for Alcohol, Revised (CIWA-Ar). Score consists of 10 items and can be performed in 5 minutes at the bedside. The questions include regarding following 10 items
nausea and vomiting,
anxiety,
tremor,
sweating,
auditory disturbances,
visual disturbances,
tactile disturbances,
headache,
agitation,
clouding of sensorium

0 to 7 points are assigned for each item except for the last item, which is assigned 0-4 points, with a total possible score of 67.

The CIWA-Ar is not copyrighted and may be reproduced freely. Patients scoring less than 10 do not usually need additional medication for withdrawal.

CIWA-Ar has been demonstrated to have high reliability, reproducibility, and validity. Careful and frequent monitoring with the CIWA-Ar is clinically found to be very helpful.

You can view the full survey here (pdf)

2008-02-18T16:08:00.000-08:00

Monday February 18, 2008
Vancomycin worse for MSSA ?

Vancomycin is widely used for empirical treatment of patients with suspected gram-positive bacteremia, even if its not MRSA. One Recent large case-control study from korea showed poorer outcomes for vancomycin than for β-lactams in patients with methicillin-susceptible (MSSA) bacteremia.

In a retrospective cohort study (n=294), patients who received vancomycin or teicoplanin therapy had a significantly higher S. aureus related mortality rate than did those with -lactam treatment.

Results:

In cohort study, S. Aureus Bateremia (SAB)-related mortality in patients with vancomycin treatment (37%, 10/27) was significantly higher than that in those with beta-lactam treatment (18%, 47/267) (P=0.02)

In the case-control study using the objective matching scoring system and the propensity score system, SAB-related mortality in case patients was 37% (10/27) and in control patients 11% (6/54) (P <>

Conclusion: The available evidence strongly suggest a switch from empirically started vancomycin to a -lactam as soon as MRSA has been ruled out.

References: click to get abstract/articles

1. Outcome of Vancomycin Treatment in Patients with Methicillin-Susceptible Staphylococcus aureus Bacteremia, Antimicrobial Agents and Chemotherapy, January 2008, p. 192-197

2008-02-17T08:24:00.000-08:00

Sunday February 17, 2008
Clostridium difficile-Associated Disease in the ICU Setting

Recently one retrospective observational, cohort study was performed to analyse 30-Day mortality for Clostridium difficile associated disease (CDAD) in the ICU Setting.

278 patients with CDAD admitted to an ICU were identified over a 2-year period.

The overall 30-day mortality rate was 36.7% (n = 102), Independent predictors for 30-day mortality were septic shock, ward-to-ICU transfer and increasing APACHE II scores
The attributable mortality associated with CDAD was estimated to be 6.1%
CDAD was associated with an excess ICU length of stay (2.2 days)
CDAD was associated with an excess hospital length of stay (4.5 days)

Editors' note: C.diff is well known to intensivists. Objective of above post is to reinforce the high suspicion towards C. diff.

References: click to get abstract/articles

1. Analysis of 30-Day Mortality for Clostridium difficile-Associated Disease in the ICU Setting - Chest. 2007; 132:418-424

2008-02-16T10:25:00.000-08:00

Saturday February 16, 2008
Synergistic agents for Daptomycin

Daptomycin is the first approved member of a new class of antibiotics, namely the cyclic lipopeptides. Daptomycin has rapid bactericidal activity against Gram-positive pathogens.

Daptomycin was shown to be not inferior to antimicrobial standard therapy for Staphylococcus aureus bacteremia and right-sided endocarditis.

This is of interest to know that there is a marked synergy between daptomycin and both rifampin and ampicillin against vancomycin-resistant enterococci (VRE) - despite high-level of ampicillin resistance alone. Also most strains of MRSA are found to have synergism between daptomycin and oxacillin despite it shows resistant alone to oxacillin (as in case of ampicillin in VRE). Ampicillin-sulbactam, ticarcillin-clavulanate, or piperacillin-tazobactam showed synergy comparable to or greater than daptomycin with oxacillin.

It may be of clinical benefit to add synergistic agents while using Daptomycin as it is a 'concentration-dependent' drug.

References: click to get abstract/articles

1. Synergy of Daptomycin with Oxacillin and Other ß-Lactams against Methicillin-Resistant Staphylococcus aureus Antimicrobial Agents and Chemotherapy, August 2004, p. 2871-2875, Vol. 48, No. 8

2. Daptomycin: A Review 4 Years after First Approval Pharmacology 2008;81:79-91

2008-02-15T10:01:00.000-08:00

Friday February 15, 2008
THAM

Introduction; In patients with acute respiratory distress syndrome (ARDS), permissive hypercapnia is a strategy to decrease airway pressures to prevent ventilator-induced lung damage by lowering tidal volumes and tolerating higher arterial carbon dioxide tension. A pure respiratory acidosis generally does not require alkali therapy. Alkali therapy is indicated for either a metabolic acidosis or a mixed acidosis. The choice of buffer is based on type of acidosis, cardiorespiratory status, and lung mechanics.

Problem with NaHCO3: Slow infusions of NaHCO3 can be used to treat non-anion gap metabolic acidosis and some forms of increased anion gap acidosis. But using NaHCO3 to treat type A (hypoxia-related) lactic acidosis can be hazardous, particularly under conditions of hypoxemia, inadequate circulation, and limited alveolar ventilation.

THAM: Under above circumstances, THAM is the preferable buffer because it does not increase PaCO2 and is excreted by the kidneys. Tromethamine (THAM) is a sodium-free alkalinizing agent that acts as a hydrogen ion (proton) acceptor. It is a weak base that combines with hydrogen ions from carbonic acid to form bicarbonate and cationic buffer. Administration of tromethamine decreases hydrogen ion concentration, which results in a decrease in carbon dioxide concentrations and an increase in bicarbonate concentrations. The administration of Tham also increases urine output through osmotic diuresis. Excretion of electrolytes and CO2 is also increased. Urine pH is raised along with the excretion of electrolytes.

Usual Dose:

Dose in ml's of 0.3M THAM = (1.1) (Wt. in Kg) (normal HCO3 – Pt’s HCO3)

Dose in ml’s of 0.3M THAM = body wt in kg X base deficit in MEq/L x 1.1

Total dose should be administered over a period not less than 1 hour via central line..3M THAM solution is available as premix and is contra-indicated in renal failure, anuria and hyperkalemia. It may cause transient hypoglycemia and respiratory depression.

2008-02-14T19:55:00.000-08:00

Thursday February 14, 2008
Alinia(Nitazoxanide) in Clostridium Difficile Colitis

Beside Vancomycin and Flagyl, an adjuvant treatment may be use in C. diff. Colitis with Alinia (Nitazoxanide), 500 mg twice daily. Actually, emerging literature is showing it to be a promising treatment in cases where metronidazole fails to eradicate C.diff.

Nitazoxanide is an FDA approved drug to treat parasitic diseases of the gastrointestinal tract. It is very widely use as an antiprotozoal agent in pediatric patients with diarrhea. The drug acts by blocking and interfering with anaerobic metabolic pathways, and has been shown to have excellent activity against C. difficile. Limited but postive literature shows its value in C.dif. colitis both as an adjuvant as well as in metronidazole failed C.diff. colitis.

References: click to get abstract/article

1. Clostridium difficile colitis that fails conventional metronidazole therapy: response to nitazoxanide, Journal of Antimicrobial Chemotherapy 2007 59(4):705-710

2. Compassionate Use of Nitazoxanide for the Treatment of Clostridium Difficile Infection - clinicaltrials.gov

3. In Vitro and In Vivo Activities of Nitazoxanide against Clostridium difficile - Antimicrob Agents Chemother. 2000 September; 44(9): 2254–2258.

4. Nitazoxanide for the treatment of Clostridium difficile colitis. , Clin Infect Dis. 2006 Aug 15;43 (4):421-7 16838229

2008-02-13T08:24:00.000-08:00

Wednesday February 13, 2008

Q; Name few drugs which can be use in VRE (Vancomycin-resistant enterococcus) Meningitis ?

A; New growing literature is showing that IV and even PO Zyvox (linezolid) should be the first line of treatment in VRE Meningitis as it has a very good penetration in CSF.

Other viable choices are chloramphenicol, Ampicillin (or penicillin) and Synercid (Quinupristin/dalfopristin).

Reference: click to get abstract/article

1. Successful treatment of vancomycin-resistant enterococcus meningitis with linezolid: Case report and review of the literature Critical Care Medicine. 29(12):2383-2385, December 2001.

2008-02-12T11:05:00.000-08:00

Tuesday February 12, 2008
Precedex® (dextromedetomidine) - better?

Precedex is now a commonly used drip in ICUs due to its simultaneous anxiolytic, anesthetic, hypnotic, and analgesic properties and moreover it does not depress respiration. But still cost is a major concern to prescribe this medicine.

A recent study published in JAMA 1 found Dexmedetomidine superior to Lorazepam for sedation. Dexmedetomidine induces sedation via different central nervous system receptors than the benzodiazepine drugs and may lower the risk of acute brain dysfunction. Interestingly, there was no difference in cost.

Design: It was a double-blind, randomized controlled trial.

Number: 106 adult mechanically ventilated medical and surgical ICU patients. Patients were sedated with dexmedetomidine or lorazepam for as many as 120 hours.

Scales used:

Richmond Agitation-Sedation Scale (RASS).
Patients were monitored twice daily for delirium using the Confusion Assessment Method for the ICU (CAM-ICU).

Results :

Sedation with dexmedetomidine resulted in more days alive without delirium or coma (median days, 7.0 vs 3.0)
a lower prevalence of coma (63% vs 92%)
Patients sedated with dexmedetomidine spent more time within 1 RASS point of their sedation goal compared with patients sedated with lorazepam (median percentage of days, 80% vs 67%)
The 28-day mortality in the dexmedetomidine group was 17% vs 27% in the lorazepam group
cost of care was similar between groups

The 12-month time to death was 363 days in the dexmedetomidine group vs 188 days in the lorazepam group

Conclusion: In mechanically ventilated ICU patients managed with individualized targeted sedation, use of a dexmedetomidine infusion resulted in more days alive without delirium or coma and more time at the targeted level of sedation than with a lorazepam infusion.

Related previous pearl: Regarding Dexmedetomidine (Precedex)

Reference: click to get abstract/article

1. Effect of Sedation With Dexmedetomidine vs Lorazepam on Acute Brain Dysfunction in Mechanically Ventilated Patients , The MENDS Randomized Controlled Trial, JAMA. 2007;298(22):2644-2653.

2008-02-11T15:17:00.000-08:00

Monday February 11, 2008
LMA insertion - an excellent animation video

This video is included in our video section

2008-02-10T21:46:00.000-08:00

Sunday February 10, 2008
Venous PH

Q: During or immediately following CPR, and in hemodynamic shock which PH is more worthwhile to follow ?

A: Venous PH

During shock state, venous blood is a more accurate reflection of metabolism in tissues. It may be of benefit to follow the trend in venous PH to measure the improvement of shock following CPR and hemodynamic instability.

Reference: click to get abstract/article

Difference in acid-base state between venous and arterial blood during cardiopulmonary resuscitation, NEJM, Number 3, Volume 315:153-156, July 17, 1986

2008-02-09T21:39:00.000-08:00

Saturday February 9, 2008
Adjuvant treatment in Ethylene Glycol toxicity

Q: Which 2 very easily available and cost-effective drugs should be added as an adjuvant treatment in Ethylene Glycol toxicity (though mostly forgotten) ?

A: Thiamine 100 mg IV daily and Pyridoxine 100 mg IV daily

One of the metabolite of Ethylene Glycol is Glycolic acid which converts into Glycoxylic Acid and remains toxic. Thiamine and Pyridoxine converts Glycoxylic Acid into non-toxic metabolites and decreases long term toxic effects of Ethylene Glycol.

Related previous pearl:

Ethanol drip in Ethylene Glycol toxicity

Treating Ethylene Glycol poisoning

2008-02-08T11:13:00.000-08:00

Friday February 8, 2008
Dialysis and central catheter's diameter !

Internal diameter of each lumen of dialysis catheter is about twice the diameter of each lumen in a triple-lumen central venous catheter.

Clinical application: As per Hagen-Poiseuille equation, just 2 fold increase in radius increase flow by 16 fold.

2008-02-07T11:34:00.000-08:00

Thursday February 7, 2008
Sodium Bicarbonate in contrast induced nephropathy (CIN) - a risk ?

Sodium Bicarbonate is increasingly being used to prevent contrast induced nephropathy which was based on a small study (1). The role of this prophylaxis is being questioned by a recent large retrospective study from Mayo (2).

Groups:

sodium bicarbonate,
N-acetylcysteine, and
the combination of sodium bicarbonate with N-acetylcysteine

Contrast nephropathy was defined as postexposure creatinine elevation of 25% or >0.5 mg/dl within 7 days of contrast exposure.

Total numbers:

A total of 11,516 contrast exposures in 7977 patients had creatinine values available for review before and after contrast exposure.

Sodium bicarbonate was used in 268 cases,
N-acetylcysteine was used in 616 cases, and
both agents were used in combination in 221 cases

Results:

Use of sodium bicarbonate alone was associated with an increased risk of contrast nephropathy compared with no treatment
N-acetylcysteine alone and in combination with sodium bicarbonate was not associated with any significant difference in the incidence of contrast nephropathy.

Conclusions: The use of intravenous sodium bicarbonate was associated with increased incidence of contrast nephropathy.

But also note, recent REMEDIAL trial, showed that the strategy of volume supplementation by sodium bicarbonate plus NAC seems to be superior to the combination of normal saline with NAC in preventing CIN in patients at medium to high risk. (3)

Editors' note: So far, it appears except for adequate hydration, most of the therapies have no consistent track of advantage and results are variable.

References: click to get abstract/article

1. Prevention of contrast-induced nephropathy with sodium bicarbonate: A randomized controlled trial. JAMA 2004; 291:2328-2334.

2. Sodium bicarbonate is associated with an increased incidence of contrast nephropathy: A retrospective cohort study of 7977 patients at Mayo Clinic. Clin J Am Soc Nephrol 2008; 3:10-18.

3. Renal Insufficiency Following Contrast Media Administration Trial (REMEDIAL). A randomized comparison of 3 preventive strategies. Circulation 2007; DOI:10.1161/CIRCULATIONAHA.106.687152.

2008-02-06T06:55:00.000-08:00

Wednesday February 6, 2008

Case: 52 year old male is back from cardiac angioplasty with abciximab (ReoPro) infusion. Pre-cath labs were normal. CBC was send per protocol after 4 hours of abciximab infusion and lab call with critical platelet level of 62. Abciximab was stopped and hematology consulted. Hematology advised to restart abciximab !!

Pseudothrombocytopenia

Pseudothrombocytopenia is a common phenomenon with patients on abciximab (ReoPro). It is a benign condition and is not a real thrombocytopenia as platelets actually clump in collecting tubes containg EDTA. It is an important diagnosis to make. Diagnosis can be made by reviewing peripheral blood film or drawing blood in citrated or heparinized tube. It is not clear why abciximab cause more EDTA-induced platelet clumping.* EDTA (Ethylenediaminetetraacetic acid) is a commonly used anticoagulant in sampling tubes for blood counts.

References: click to get abstract/article

1. Occurrence and clinical significance of pseudothrombocytopenia during abciximab therapy J Am Coll Cardiol. 2000 Jul;36(1):75-83.
2. Abciximab-Associated Pseudothrombocytopenia - Circulation. 2000;101:938
3. EDTA dependent pseudothrombocytopenia caused by antibodies against the cytoadhesive receptor of platelet gpIIB-IIIA - Journal of Clinical Pathology 1994;
47:625-6304. Pseudothrombocytopenia Volume 329:1467 Nov. 11, 1993

2008-02-05T14:46:00.000-08:00

Tuesday February 5, 2008

Q: Can Wernicke's Encephalopathy be iatrogenic in ICU ?

A: Yes, it can be precipitate in any patient by glucose (like D-5, D-10 or D-50) administration who is thiamine deficient. It is not limited to alcoholics and can happen in any nutritionally deficient patient. It is always a good idea to add thiamine in glucose drip in patients who are at risk of Wernicke's Encephalopathy. Disorder was described 25 years ago by Carl Wernicke as a triad of

acute mental confusion
ataxia
opthalmoplegia

Read a case of Wernicke's encephalopathy. in a non-alcoholic patient with MRI findings here (Ref.: The New England Journal of Medicine, Kaineg and Hudgins 352 (19): e18, May 12, 2005)

Also full review article Wernicke's encephalopathy at emedicine.com

2008-02-04T09:34:00.000-08:00

Monday February 4, 2008
What to do in case of accidental esophageal intubation !

Editors' note: The following video is a practice or opinion of some intensivits but not proved or recommended by clinical trials.

Total video time: 1 minute 24 secs

2008-02-03T09:23:00.000-08:00

Sunday February 3, 2008
Bimanual Laryngoscopy - BURP !!

One 'trick' to enhance successful intubation is using 'Bimanual Laryngoscopy'.
Its different from cricoid pressure as explained in video.

Its also called BURP: pressure backwards,upwards and to the right.

source:

Airwaycam.com

2008-02-02T08:52:00.000-08:00

Saturday February 2, 2008
Arterial line colonization and infection

In this month of Critical Care Medicine 1, a study published from australia: Prospective study of peripheral arterial catheter infection and comparison with concurrently sited central venous catheters. It was prospective 24-month cohort study. 331 arterial catheters were observed for 1,082 catheter days, and 618 central venous catheters for 4,040 catheter days.

All catheters were inserted by trained personnel under aseptic conditions, and management was standardized.

Results:
The incidence per 1,000 catheter days of catheter-related bloodstream infection was 0.92 for arterial catheters and 2.23 for central venous catheters.
Arterial catheter colonization was not significantly different than that in central venous catheters.
Femoral arterial catheters were colonized more often than radial arterial catheters
Colonization was significantly higher when the catheter was inserted in the operating theater or emergency department compared with the ICU !

Conclusions: The incidence of catheter-related bloodstream infection from arterial catheters was low. However, both arterial catheter colonization and rates of catheter-related bloodstream infection were similar to those in concurrently sited and identically managed central venous catheters. By inference, the arterial catheter should be accorded the same degree of importance as the central venous catheter as a potential source of sepsis.

Reference: click to get abstract

Prospective study of peripheral arterial catheter infection and comparison with concurrently sited central venous catheters - Critical Care Medicine. 36(2):397-402, February 2008.

2008-02-01T12:11:00.001-08:00

Friday February 1, 2008
Procedure video - IJ central line under ultrasound

Related previous video: Ultrasound windows for venous catheter placement