Wednesday, February 28, 2007

Wednesday February 28, 2007

Q: Propofol causes deficiency of which essential element ?

A:
Zinc

Though propofol cause greater urinary losses of zinc and lower serum zinc concentrations, the actual clinical implication is not established.


Related previous Pearl: Essential trace elements


Reference:

1.Trace element homeostasis during continuous sedation with propofol containing EDTA versus other sedatives in critically ill patients - Intensive care medicine. Supplement (Intensive care med., Suppl.) , 2000, vol. 26, n 4, pp. S 413-S421

Tuesday, February 27, 2007

Tuesday February 27, 2007
'insensible' water loss

In ICU, total volume status is the key to whole management of patient care. Often ignored aspect is 'insensible' water loss. Most important point to understand: this is loss of pure water without any associated solute loss. 'Insensible' water loss happens via 2 routes.

  • Water evaporation via skin (call transepidermal diffusion), which is about 400 ml/day in healthy adult and
  • Water evaporation loss from the respiratory tract, which is also about 400 ml/day in healthy adult

In ICU patients, 'insensible' water loss is higher due to fever, increase catabolism, surgical status and higher minute ventilation. It is estimated that in hospitalized patient it reaches upto 1200 ml/day or may be higher in sicker or surgical patients. The management should take into consideration of full clinical picture based on blood pressure, heart rate, CVP, urine output etc. In ventilated patients , 'insensible' water loss can be minimized by humidification of inspiried gas at 37°C.

Surgery itself is a big contributor in 'insensible' water loss. Per one study during routine cardiac surgery in adults, insensible losses of 1 litre are to be expected 1. See our previous pearl in this regard -
fluid-facts .


Another related previous pearl:
Arterial line and volume assessment




References:

1.
Insensible fluid loss during cardiac surgery - Critical Care 2001, 5(Suppl 4):2

Monday, February 26, 2007


Monday February 26, 2007

Regarding balloon rectal tube (rectal catheter)

Sometime, you wonder why nurse is asking for your orders to place rectal balloon catheter (Flexi-Seal® )? The answer is: The safety of longer-term rectal catheter use has not been established yet and in case if it is left for longer period of time, may cause rectal perforation or anorectal necrosis secondary to pressure or barotrauma. Rectal balloon catheter insertion requires a physician’s order. It is a safe practice to identify the time period with its order like, insert flexi-seal for 48 hours.

Rectal balloon catheters should be avoided in patients with recent rectal or prostate workup, clotting disorders, impaired immune status and hemodynamic instability including recent MI or septic shock to avoid rectal mucosal necrosis. If placed long term, the balloon requires a periodic inflation and deflation to help prevent injury to the rectal mucosa, though it has been claimed that new version of Flexi-seal is more safe and does not require periodic baloon deflation.

See product details from commercial company by clicking
here.

icuroom.net has no financial relationship with any company



References:

1. Managing incontinence using technology, devices, and products. Nurs Res. 2004;53(6 suppl):S42–S48.
2. Caring for patients with fecal incontinence: external management. WCET J. 1998;18(2):13–15
4. Assessment and management of the patient with fecal incontinence. In: Doughty DB (ed). Urinary and Fecal Incontinence: Current Management Concepts. St. Louis, Mo: Mosby Elsevier;2006:457–489

Sunday, February 25, 2007

Sunday February 25, 2007

Before today's tip we have a question from one of our visitor

Q; Can you please provide the reference to time constraint of 6 to 12 hours, described in your pearl regarding propofol use on feb. 17, 2007 ?

A; Above pearl was taken from prescribing manual and official site diprivan.com. Click here to reach the relevant page.



Is oxygen supply intact ?

This sounds silly but often when patient starts acutely desaturating, it is the oxygen supply which is disconnected from wall. Anedoctal experiences showed that this is a common scenario while BiPAP gets applied. Often, oxygen supply gets forgetten at oxygen port or frequently gets disconnected with patient movement. Check if oxygen supply is off or lying on the floor!

Saturday, February 24, 2007

Saturday February 24, 2007
Ethylene Glycol poisoning - II

Continuing our theme from yesterday on
Ethylene Glycol poisoning, actual antidote or first line therapy is Fomepizole (Antizol) with fewer side effects.

Fomepizole blocks alcohol dehydrogenase. Fomepizole is administered as 15 mg/Kg (up to 1 Gm) initially, then 10 mg/Kg q12h times four doses, and then 15 mg/Kg q12 hours until ethylene glycol level <10>

In patients who are symptomatic, hemodialysis should be considered. Hemodialysis efficiently clears ethylene glycol and toxic byproducts and corrects acidosis.

If the patient does receive dialysis, treatment with fomepizole or ethanol should continue to be provided so as to block the ongoing conversion of Ethylene Glycol to its toxic metabolites while dislysis is being preformed. Both fomepizole and ethanol will be dialyzed off and their dosing needs to be adjusted accordingly.


Bonus Pearl: Fomepizole can also be use as antidote in Methanol overdose.

Friday, February 23, 2007

Friday February 23, 2007
Ethanol drip in Ethylene Glycol


Q; How you write Ethanol drip in Ethylene Glycol poisoning assuming you don't have Fomepizole or Dialysis available ?


A: Ethylene Glycol poisoning is common and can have bleak outcomes. Intensivists should be aware of all the possible interventions available. Antidotal therapy is based on preventing the alcohol dehydrogenase enzyme from metabolizing ethylene glycol into toxic byproducts. In case Fomepizole or Dialysis is not available, Ethanol will competitively inhibit alcohol dehydrogenase. But the serum ethanol level must be monitored frequently.

Therapeutic ethanol is administered in a bolus followed by a continuous infusion. Initially, 7.5 to 10 mL/Kg of 10% ethanol, in D5W, is administered over 30 minutes. Then, a continuous infusion of 1 to 2 mL/Kg/hr of 10% ethanol is infused until the patient has eliminated all of the EG from his serum. It is important to keep the serum ethanol level at 100 to 150 mg/dL so as to completely inhibit the alcohol dehydrogenase enzyme.

Thursday, February 22, 2007

Thursday February 22, 2007
Often missed bedside tip !

If oliguria is not present in the face of clinical hypovolemic shock, evaluate the urine for the presence of osmatically active substances such as glucose, radiographic dye or toxins.

Tuesday, February 20, 2007

Tuesday February 20, 2007
EPR


Dr. Patrick M. Kochanek from Safar Center for Resuscitation Research, Pittsburgh, PA delivered the keynote speech on "Beyond CPR" at 36th Critical
Care Congress of The Society of Critical Care Medicine at Orlando, Florida on sunday feb. 18, 2007. The message was one word - EPR.

Emergency Preservation and Resuscitation


EPR is induction of profound hypothermia for trauma victims who experience exsanguination cardiac arrest.

In lab, canines received 20 L of a 2°C saline aortic flush to achieve a brain temperature of 10°C to 15°C. EPR lasted 60 minutes and was followed by a 2-hour resuscitation by cardiopulmonary bypass. The conventional group with CPR dogs were maintained at 38.0°C. In the EPR groups, mild hypothermia (34°C) was maintained for either 12 (EPR-I) or 36 (EPR-II) hours. Function and brain histology were evaluated 60 hours after rewarming in all dogs.

EPR was found superior to conventional CPR in facilitating normal recovery after cardiac arrest from trauma and prolonged hemorrhage. Also, prolonged mild hypothermia after EPR was critical for achieving intact neurological outcomes.

It was amazing to watch videos of normal dog after these life-threatening experiments with EPR.


Reference: click to get abstract/article

1.
Induction of Profound Hypothermia for Emergency Preservation and Resuscitation Allows Intact Survival After Cardiac Arrest Resulting From Prolonged Lethal Hemorrhage and Trauma in Dogs - Circulation. 2006;113:1974-1982.

Monday, February 19, 2007

Monday February 19, 2007
Soda-bicarb to prevent contrast induced nephropathy


Q:
How you write the drip oof soda bicarbonate in preventing contrast induced nephropathy ?


A: Use 154meq/L of sodium bicarbonate (3 amps) in 1 litre of D5W.
Give 3ml/kg/hr one hr prior to the exam.
Give 1ml/kg/hr during the exam and for 6 hours after the exam.

Sunday, February 18, 2007

Sunday February 18, 2007

Q: How IV (intravenous) DDAVP (desmopressin) should be given?

A: DDAVP, short name of 1-deamino-8-D-arginine vasopressin and also known as desmopressin is use for varity of reasons in ICUs including uremic bleeding diasthesis, some platelet disorders, to boost the plasma level of factor VIII and von Willebrand factor (VWF) and in diabetes insipidus. It may be given as nasal spray or subcutaneous injection but in ICUs mostly get administrated via IV route.DDAVP should be diluted in 100 ml of normal saline and given by slow intravenous infusion over 30 minutes. The usual dose is 0.3 mcg/kg. Rapid infusion may result in tachycardia, flushing, tremor and abdominal discomfort. Also thrombosis and even myocardial infarction after an infusion of DDAVP has been reported and should be used with caution in patients with signs of arterial disease.

Saturday, February 17, 2007

Saturday February 17, 2007
Regarding propofol use !


Q: What is the time limit on use once propofol bottle / vial is broken?

A: When propofol is used as an anesthetic from a vial as in intubations or cardioversions, the infusion be completed within 6 hours after the vial is opened. Any unused portion of propofol must be discarded at the end of the procedure or at 6 hours, whichever occurs sooner. In the ICU, if propofol is administered directly from its original container, the tubing and any unused portion must be discarded after 12 hours (some places allow upto 24 hours). The infections appears to be a risk factor in prologed unused propofol.

Friday, February 16, 2007

Friday February 16, 2007
Propylene Glycol and Ativan


Being an intensivist it is imperative to understand the dangers of propylene glycol with Lorazepam drip - particularly if it is continued beyond 48 hours and require higher dose. Any unexplained high anion gap metabolic acidosis with elevated osmol gap, should prompt the diagnosis of propylene gylcol toxicity. It may also cause CNS depression, arrhythmias and renal dysfuntion. Propylene glycol is a viscous, colorless liquid solvent used for many drugs with poor aqueous solubility including lorazepoam, diazepam, esmolol, nitroglycerin, pentobarbital, phenytoin, Bactrim and others.

References: click to get abstract/article

1. Propylene Glycol-Induced Lactic Acidosis in a Patient with Normal Renal Function: A Proposed Mechanism and Monitoring Recommendations - The Annals of Pharmacotherapy: Vol. 39, No. 10, pp. 1732-1735., 2005

2.
Propylene Glycol Toxicity: A Severe Iatrogenic Illness in ICU Patients Receiving IV Benzodiazepines Chest. 2005;128:1674-1681.

3.
Hyperosmolar Metabolic Acidosis and Intravenous Lorazepam - Volume 347:857-858, Number 11 NEJM, sept. 12, 2002.

Thursday, February 15, 2007

Thursday February 15, 2007

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;47:625-630
4. Pseudothrombocytopenia Volume 329:1467 Nov. 11, 1993

Tuesday, February 13, 2007

Tuesday February 13, 2007
ECMO - followup ABGs


Continuing our theme from yesterday on
ECMO, here is a quick tip.

To see serial improvements in PO2, it is important to draw and follow ABGs from radial arterial lines. It will provide better index of oxygenation of whole body (instead of drawing from femoral line as it may be falsely high due to ECMO effect).

Monday, February 12, 2007

Monday February 12, 2007
ECMO !

ECMO is a standard practice in neonatal and pediatric ICUs to support pulmonary failure but remained a very last resort in adult ICUs due to the high technical demands, cost, and risk of bleeding (required anticoagulation). The major reason ECMO remained unused in adult ICUs is a negative study done about 27 years ago. The National Institutes of Health trial of ECMO in severe acute respiratory failure in 1979 showed mortality in excess of 90%.

ECMO is a pulmonary version of CVVHD ! ECMO could be a bridge till definite therapy is sought or till healing occurs. Technically, VV or VA (veno-veno or veno-arterial) ECMO can provide sufficient oxygenation for several weeks.

The biggest advantage of ECMO in ARDS is the minimal requirement of positive pressure mechanical ventilation as you now need only little breaths with some tidal volume and PEEP, to prevent atelectasis. You rest the lung till healing occurs.

Is it time to think out of box again ?



Trial to watch:
CESAR Trial - click - (Conventional ventilation or ECMO for Severe Adult Respiratory Failure) - The CESAR trial (180 patients) is closed now and results of the trial are known in late 2007.


Click to get bigger image

Sunday, February 11, 2007

Sunday February 11, 2007
About white coat and stethoscope !

Editors' note: We received following email but we are holding sender's name on request.


"...Thanks for such a wonderful work. I visit your site often. I am a pulmonary and critical care physician and now at the verge of retirement. In last few years I have noticed the trend among new house staff to ignore 2 basic arsenals of patient care, white coat and stethoscope. I see house staff wearing only scrubs which make them look 'cool' and I guess this has been taken from various TV medical shows. But while not doing procedure, our patient will appreciate more and will feel better if we have our coat on and stethoscope in pocket instead of around the neck. You may cure your patient half by just putting stethoscope on his chest. Its a big psychological arsenal to make him and his family feel well (even if they are on ventilator). Indeed xrays, echocardiogram, ultrasounds and now in this era CAT and MRI scans may give more inside knowledge but don't forget one basic tip - a touch of healing hand. Appear like a doctor if you want to be a doctor...

Thank you."

Saturday, February 10, 2007

Saturday February 10, 2007
Aprotinin and CABG

The majority of patients undergoing cardiovascular surgery routinely receive antifibrinolytic therapy - aminocaproic acid, tranexamic acid or aprotinin during and after procedure to control bleeding. In last couple of years, use of aprotinin has been questioned following coronary artery bypass grafting, particularly in view of availability of safer and less expensive alternatives ie aminocaproic acid and tranexamic acid.

One major article published last year in The New England Journal of Medicine concluding that the use of aprotinin was associated with a dose-dependent doubling to tripling in the risk of renal failure requiring dialysis among patients undergoing primary or complex coronary-artery surgery. Also, it was suggested that for the majority of patients undergoing primary surgery, evidence of multiorgan damage involving the heart (myocardial infarction or heart failure) and the brain (encephalopathy) in addition to the kidneys shows a generalized pattern of ischemic injury
1.

Same group, published an article this week in JAMA
2, looked into mortality data of 3876 patients from 62 medical centers assessed at 6 weeks, 6 months, and annually for 5 years after CABG surgery.

Study contrast 3 groups

  • aminocaproic acid and tranexamic acid,
  • aprotinin, or
  • no antibleeding agent (control)

Study found that Aprotinin treatment was associated with significantly increased long term mortality compared with control, whereas neither aminocaproic acid nor tranexamic acid was associated with increased mortality.


Note: FDA has issued a relabeling of aprotinin on December 15, 2006, confining it to use only in high-risk coronary artery bypass graft patients.


Previous related pearl: Should we abandon Aprotinin ?




References / suggested readings: Click to get article/abstract

1.
The Risk Associated with Aprotinin in Cardiac Surgery - NEJM Jan. 26, 2006 Volume 354:353-365
2.
Mortality Associated With Aprotinin During 5 Years Following Coronary Artery Bypass Graft Surgery - JAMA. 2007;297:471-479, Vol. 297 No. 5, February 7, 2007 - full text is available free

Friday, February 9, 2007

Friday February 9, 2007


Q: In the close enviroment of the ICU it is sometimes difficult to be far off during portable radiographs. It is best to avoid any x-ray exposure or have a shield but in case, what is the minimum distance should be kept to minimize hazards of radiation?

A: One should stand at least 6 feet from the patient and the machine. In all cases, the direct beam should be avoided. Often, a nurse must hold an uncooperative or mentally agitated patients. In such situations, protective lead apron and gloves should be wear.

Thursday, February 8, 2007

Thursday February 8, 2007


Q: How much calories each ml of Diprivan (propofol) provides to patient?

A: 1.1 kilocalories per mL

The emulsion portion of the DIPRIVAN is identical to that found in Intralipid 10% . Triglycerides account for about 85% of the total calories. Triglyceride level should be check in patient who receive prolong infusion to avoid pancreatitis.

Wednesday, February 7, 2007

Wednesday February 7, 2007
The GlideScope® Video Laryngoscope

The GlideScope® Video Laryngoscope utilizes a video camera embedded into a plastic laryngoscope blade. It provide a clear, real time view of the patient's airway, enabling uncomplicated intubations. It does not require direct line of sight as view can be watch on separate screen.

More info can be obtained from Dr. Doyle's site

Related previous pearls:

Airtraq
Light Wand
How many attempts to intubate?

Note: icuroom.net has no financial relationship with any company. Info provided here is 100% for educational purpose.

Tuesday, February 6, 2007

Tuesday February 6, 2007

Q; Name atleast one other condition which can give rise to osborn wave (electrocardiographic J wave usually associated with hypothermia) ?

A; cocaine use

Osborn waves are famous for their association with hypothermia but there are many other conditions which can produce similar EKG 'j' wave findings under normothermia including cocaine use, haloperidol overdose, and left ventricular hypertrophy due to hypertension, after cardiac resuscitation and in severe hypercalcemia, cardiac ischemia and central nervous system injury.

Objective of this question is to understand that osborn wave is not a diagnostic of hypothermia and other conditions should be considered.


References: Click to get article/abstract

1. The Osborn wave of hypothermia in normothermic patients - Clin Cardiol.1994 May;17(5):273-6


Monday, February 5, 2007

Monday February 5, 2007
If there is bleeding with LMWH


If protamine is given within 4 hours of the enoxaparin (Low Molecular Weight Heparins - LMWH), then a neutralizing dose is: 1 mg of protamine per 1 mg of enoxaparin. The IV protamine should be administered slowly atleast over 10 minutes as rapid infusion may cause anaphylactoid type reaction. May repeat half of earlier dose of protamine after 6 hours with postulation that half life of enoxaparin is longer than protamine.

LMWH, dalteparin (Fragmin) appears to be more responsive to protamine reversal.

2 bonus pearls

1. Protamine does not help in reversing bleeding from Fondaparinux (Arixtra). Only supportive treatment should be given with mean half-life of fondaparinux of 17-21 hours in mind.

2. Fresh frozen plasma is ineffective in reversal of LMWH to achieve hemostasis and should not be use in these situations.



References: Click to get article/abstract

1. Accidental overdosage following administration of Lovenox - rxlist.com
2. Incomplete Reversal of Enoxaparin Toxicity by Protamine: Implications of Renal Insufficiency, Obesity, and Low Molecular Weight Heparin Sulfate Content - Obesity Surgery, Volume 14, Number 5, 1 May 2004, pp. 695-698(4)

Sunday, February 4, 2007

Click to get bigger image


Sunday February 4, 2007
Basics of High Frequency Oscillatory Ventilation (HFOV)


Editors' note: Setup and management of HFOV should be done under experienced physician. Following are just basics to understand the dials and simple maneuvers for the beginers. Other details can be found in literature somewhere else.

HFOV is not an initial form of mechanical ventilation. It always get transit from conventional mechanical ventilation.


Indications

Patients with severe ARDS having Pplat more than 30 - 35 cm H2O along with high FiO2 and worsening acidosis and all conventional mode of ventilation is exhausted.

Check for things before initiating HFOV

1. Need of suction. Bronchoscope should be done in conventional mode before switching to HFOV.
2. Good sedation, analgesia, and possible need of neuromuscular blockade.
3. Ensure euvolemia. Intial phase of HFOV may drop BP in hypovolemia.

Initial Settings (RTs usually do the rest but you have to provide MAP, frequency and amplitude)

A) TO IMPROVE OXYGENATION

MAP (Mean Airway Pressure): Initiated at 5 cm H20 higher than the MAP during conventional ventilation. The MAP should be raised only in 2-3 cm H2O increments at 30 – 60 minute intervals to improve oxygenation. Ideal is not to exceed beyond 35 cm H2O.

FiO2: Start at 1.00 and wean slowly towards .4

IT or I:E ratio: Set IT to 33% (can go up to max of 50% if difficulty with oxygenation)

Flow: Start at 15 LPM but increase if oxygenation remains issue.

B) TO CORRECT HYPERCAPNIA

Amplitude of oscillation (P): The amplitude is initiated at either a value where vibration can be seen down to mid-thigh. Amplitude is increased by 10 to 20 cm H2O (value runs from 0-100 cm H2O). You may start arbitrarily somewhere between 70-90 cm H20.



Frequency: It can be set arbitrarily at 5 Hz. Some experts prefer initial setting at 7 and target to go up as oxygenation gets better. (Value runs from 3-15 Hz)



Most important trick to remember

Increasing the amplitude and decreasing the frequency (Hz) will lower the PaCO2. Conversly, decreasing amplitude and increasing frequency (Hz) will increase PaCO2. If PaCO2 worsens, increase amplitude in 10 cmH2O increments every 30 minutes. After maximum amplitude is achieved, and oxygenation remains poor, decrease Hz to the minimum setting of 3 Hz.

Weaning

Wean FiO2 first.
Second wean MAP slowly 2-3 cm H2O at a time till reach at least 24 cm H2O.
Switch to convetional ventilator once patient is stable.

Complications

ETT obstruction - suction
HYPOTENSION - IVF boluses or pressor as clinically indicated
PNEUMOTHORAX - Watch for chest vibration (stethoscope does not work due to noise) or quickly rising PCO2 or desaturation. Confirm PTX with CXR.


Saturday, February 3, 2007

Saturday February 3, 2007
MUST protocol


The Multiple Urgent Sepsis Therapies (MUST) Protocol combines current evidence-based sepsis therapies into a single practical pathway. The MUST Protocol originated at the Beth Israel Deaconess Medical Center and was first implemented in November, 2003.

Click
here to get MUST Protocol Handbook
(take little time to download, 24 pages - pdf file)

Click
here to get MUST Protocol flowsheet



References: Please click to get abstract


1. Implementation and outcomes of the Multiple Urgent Sepsis Therapies (MUST) protocol - Critical Care Medicine. 34(4):1025-1032, April 2006.

Friday, February 2, 2007

Friday February 2, 2007


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.

Thursday, February 1, 2007

Thursday February 1, 2007
How Frequent Is Venous Thromboembolism (VTE) with HIT in Heparin-Treated Patients

Interesting meta-analysis of 10 studies done from Texas looking into frequency of DVT / VTE in heparin treated patients (include IV and SQ unfractionated heparin as well as SQ low-molecular-weight heparin (LMWH) - due to Heparin-Induced Thrombocytopenia (HIT).

They found that VTE is associated with HIT less than 1% in LMWH-treated patients, but one in eight cases in unfractionated heparin treated patients.


Clinical significance:

1. LMWH like Lovenox may be a better choice for DVT prophylaxis and other treatments than unfractionated heparin due to high incidence of HIT with it.

2. Physicians should suspect the possibility of HIT if DVT / VTE develops during or soon after unfractionated heparin use.



Reference:
How Frequently Is Venous Thromboembolism in Heparin-Treated Patients Associated With Heparin-Induced Thrombocytopenia? Chest. 2006;130:681-687