Thursday, March 30, 2006
Garlic Odor in ICU
Q: Patient with which poisoning presents with garlic odor?
A: Organophosphate poisoning.
Thursday March 30, 2006
Dilantin in Torsade
Q: Which anti-seizure drug can be use in the treatment of Torsade de pointes if conventional therapy fails?
A: Phenytoin (Dilantin).
1. Torsades de pointes therapy with phenytoin - Ann Emerg Med.1991 Feb;20(2):198-200.
2. Few case reports from literature: remarkablemedicine.com
Wednesday, March 29, 2006
Q: Once patient receive Digoxin Fragmented Antibody (DIGIFAB or Digibind), how frequent digoxin level should be measured ?
A: Digoxin level after giving Digibind will rise and will remain distorted for about 7 days. This is due to ability of Digibind to pull all of the digoxin into blood stream. These are inactive fragments and not toxic. There is no need to follow Dig level after administration of Digibind as it may be misleading.
See full review on DIGIFAB along with dose calculator here (source: fda.gov)
Tuesday, March 28, 2006
Cuff leak test - to anticipate post-extubation stridor
There are atleast 3 common ways to do cuff leak test to anticipate postextubation stridor but none has been really tested in a big scientific randomized trial. And literature is full of conflicting studies.
1. Bedside crude method: Deflate the cuff, +/- occlude the ETT and put your hand at mouth to feel exhaled air. (isn't it brutal?)
2. Record the difference between the inspiratory tidal volume and the expiratory tidal volume while the cuff around the endotracheal tube was deflated. (Average of any three values on six consecutive breaths). Cuff leak less than 110 mL is more associated with postextubation stridor.
3. Record the difference in exhaled tidal volume from before to after endotracheal tube cuff deflation. Divide this number by the exhaled tidal volume before cuff deflation. Your answer is 'percent cuff leak'. Patients with a cuff leak of less than 10% are at risk for stridor or reintubation.
Some other methods like laryngeal ultrasound has also been described in literature. Also, experts recommend to test the ability to expel secretions with an effective cough. Be aware, a low value for cuff leak may actually be due to encrusted secretions around the tube rather than to a narrowed upper airway. Reintubation equipment (including tracheostomy equipment) should be readily available during extubation and immediate postextubation period.
Related previous pearl: Spontaneous Breathing Trial (SBT)
References: Click to get abstract/article
1. Association between reduced cuff leak volume and postextubation stridor - Chest, Vol 110, 1035-1040
2. Measurement of endotracheal tube cuff leak to predict postextubation stridor and need for reintubation - J Am Coll Surg. 2000 Jun;190(6):682-7.
3. Laryngeal ultrasound: a useful method in predicting post-extubation stridor. A pilot study - Eur . Respir J 2006; 27:384-389
4. Predicting Extubation Failure - Is It in (on) the Cards? - Chest. 2001;120:1061-1063
5. Evaluation of the Cuff-Leak Test in a Cardiac Surgery Population - Chest. 1999;116:1029-1031
6. Evidence-Based Guidelines for Weaning and Discontinuing Ventilatory Support - Chest. 2001;120:375S-396S
Monday, March 27, 2006
The ‘UNLOAD’ Study
New findings from the UNLOAD study, announced at the 2006 American College of Cardiology (ACC) 55th Scientific Session Conference in Atlanta, detail immediate and long-term benefits for heart failure patients receiving ultrafiltration therapy to treat fluid overload. This is the first randomized clinical study to compare the safety and efficacy of a non- drug-based option with standard intravenous diuretic drug therapy to treat heart failure patients. UNLOAD stands for UltrafiltratioN versus IV Diuretics for Patients HospitaLized fOr Acute Decompensated Congestive Heart Failure. This prospective, randomized multi-center trial compared the immediate and long-term effects of early ultrafiltration alone, versus intravenous diuretics alone, on weight loss, symptoms and hospitalizations of patients with decompensated heart failure and fluid overload. The ultrafiltration therapy used in the trial was administered via the Aquadex FlexFlow(TM). The Aquadex FlexFlow is a mechanical system that can remove up to one liter of excess fluid from the body in two hours, or more than a gallon in eight hours. The system received marketing clearance from the U.S. Food and Drug Administration in 2002. A Standard catheter is inserted into peripheral or central vein, which connects the patient to the Aquadex FlexFlow.
Two hundred patients were enrolled at 28 medical sites. In this prospective trial, patients were randomized and placed in either the ultrafiltration group or the intravenous diuretics group, and assessed at entry and at intervals out to 90 days. There was no difference in renal function between the groups. Highlights of the UNLOAD study include statistically significant findings such as:
At 48 hours into treatment, the ultrafiltration group demonstrated a:
38% greater weight loss over standard care; and
28% greater net fluid loss over standard care.
At 90 days following hospital discharge, the ultrafiltration group demonstrated a:
43% reduction in patients requiring rehospitalizations for CHF over standard care;
50% reduction in the total number of rehospitalizations for CHF over standard care.
52% reduction in ER or clinic visits over standard care and
63% total reduction in days rehospitalized for heart failure over standard care.
The benefits in weight loss and in reduction of rehospitalization were seen in all subgroups analyzed.
The cost of the device is about $10,000, and each filter runs about $800.
Sunday, March 26, 2006
Where is my food dude !!
Is the Gut working? : Bowel sounds are not a reliable indicator of gastrointestinal function in critical illness. Bowl sound requires the presence of movement, intestinal contents and intraluminal air. Normally air is swallowed and in ventilated patients, particularly if receiving high doses of sedation or neuromuscular blocking agents do not swallow air. Because of this bowl sounds may be absent in patients whose gastrointestinal tract is working normally.
Read this quote from study of 1479 patients - Daily enteral feeding practice on the ICU, which also looked into the factors interfering with successful administration of enteral feed: "We also found that nurses tended to overestimate gastric retention as a risk factor and, more importantly, violated the protocol by discarding a gastric retention volume of less than 200 ml over 6 hours. This behavior might be the result of a misplaced ambition to achieve safer care. Although the measurement of gastric retention is an important tool for guaranteeing safe enteral feeding, no difference is reported between gastric tube and duodenal tube use among ICU patients in terms of aspiration and nosocomial pneumonia." It was recommended to give back gastric retention of less than 250 ml (per 6 hours).
Related previous pearl: Is post pyloric feeding absolute ?
Reference: (Click to get article)
Daily enteral feeding practice on the ICU: attainment of goals and interfering factors - Critical Care 2005, 9:R218-R225
Saturday, March 25, 2006
Q: What is Valentino's Syndrome ?
A: A duodenal ulcer with retroperitoneal perforation presenting with pain in the right lower quadrant is called Valentino's syndrome. Usually surgery can be avoided and treatment is hydration and antibiotics.
Read case presentation with radiological findings here.
(Reference: NEJM, Volume 354:e9, Number 10, March 9, 2006)
Friday, March 24, 2006
Is Forearm Blood Pressure Reliable ?
It is one of the common practice to use forearm as non-invasive blood pressure monitoring in case upper arm blood pressure measurements having problems. Folks from Delaware did blood pressure measurement in the forearm and then in the upper arm of 221 supine patients with their arms resting at their sides. Similar exercise was repeated with patients' head of the bed elevated at 45 degree. Analysis showed that: Noninvasive measurements of blood pressure in the forearm and upper arm cannot be interchanged irrespective of position. Important aspect of forearm BP monitoring:
1. Forearm BP measurement is not recommended but if absolutely required, as if proper-size upper arm cuff is not available, make sure correct cuff size for forearm is used.
2. Use and follow forearm Blood Pressure serially and DO NOT interchange Blood Pressure measurement with upper arm readings.
3. Be cautious that systolic, diastolic and mean forearm blood pressure measurements are higher than upper arm blood pressure measurements with following values
* Systolic BP is about 8 mm Hg higher in supine and 14 mm Hg higher at 45 degree,
* Diastolic BP is about 4 mm Hg higher in supine and 9.5 mm Hg higher at 45 degree,
* Mean BP is about 5 mm Hg higher in supine and 11 mm Hg higher at 45 degree.
Clinical Comparison of Automatic, Noninvasive Measurements of Blood Pressure in the Forearm and Upper Arm With the Patient Supine or With the Head of the Bed Raised 45?: A Follow-Up Study - American Journal of Critical Care. 2006;15: 196-205
Thursday, March 23, 2006
Can BNPs replace Pulmonary Wedge Pressure?
With BNP as a marker of fluid overload on heart, there was a lot of enthuthiasm about using it as a non-invasive mirror for PCWP. Group of physicians from Division of Cardiology, Johns Hopkins Hospital, Baltimore, Maryland studied prospectively 40 patients in the ICU requiring invasive hemodynamic monitoring. Hemodynamics were recorded simultaneously with blood sampling for both BNP and NT-proBNP. They found that due to rapidly fluctuating levels of estimated glomerular filtration rate in ICU patients - BNPs have very poor correlation with PCWP.
Related previous pearls:
BNP or Pro-BNP ? and Re. Nesiritide (Netrecor)
1. Relationship Between B-Type Natriuretic Peptides and Pulmonary Capillary Wedge Pressure in the Intensive Care Unit - J Am Coll Cardiol, 2005; 45:1667-1671
Wednesday, March 22, 2006
Spontaneous Breathing Trial (SBT) - how long - 30 minutes or 120 minutes?
Spontaneous Breathing Trial (SBT) remained one of the key clinical parameter for extubation from mechanical ventilation but there is always a debate about how long is good enough to predict successful extubation. Evidence-Based Guidelines for Weaning and Discontinuing Ventilatory Support published in chest 2001 recommends: "The tolerance of SBTs lasting 30 to 120 min should prompt consideration for permanent ventilator discontinuation."3
Earlier one study published 7 years ago in Am. J. Respir. Crit. Care Med, showed that successful extubation can be achieved equally effectively with trials targeted to last 30 and 120 minutes 1. This has been confirmed again in another study from Washington Hospital Center, Washington, DC. 164 consecutive medical ICU patients on mechanical ventilation have been evaluated. 90-minute CPAP trial has been given and RSBI was measured at 1, 30, 60, and 90 minutes of SBT. 141 patients were successfully extubated and the mean RSBI’s for successfully extubated patients were 65, 63, 64, and 65 at 1, 30, 60, and 90 minutes, respectively. It was concluded that there is little to be gained by extending the SBT beyond the first 30 minutes 2.
In this regard, read article with weaning protocols, strategies and numbers from FERNANDO FRUTOS-VIVAR, MD and ANDRÉS ESTEBAN, MD, PHD (Intensive Care Unit, Hospital Universitario de Getafe Madrid, Spain): When to wean from a ventilator: An evidence-based strategy, published in CLEVELAND CLINIC JOURNAL OF MEDICINE VOLUME 70, NUMBER 5 MAY 2003 page 389
1. Effect of Spontaneous Breathing Trial Duration on Outcome of Attempts to Discontinue Mechanical Ventilation - Am. J. Respir. Crit. Care Med., Volume 159, Number 2, February 1999, 512-518
2. Analysis of Rapid Shallow Breathing Index as a Predictor for Successful Extubation from Mechanical Ventilation - Chest 2004 126: 756S-757S.
3. Evidence-Based Guidelines for Weaning and Discontinuing Ventilatory Support- A Collective Task Force Facilitated by the American College of Chest Physicians; the American Association for Respiratory Care; and the American College of Critical Care Medicine- Chest. 2001;120:375S-396S
Tuesday, March 21, 2006
Rapid Response Team / Medical Emergency Team
Overall impression and anecdotal experiences are in favor of Rapid Response Team. Also IHI recommends it as part of "100,000 Lives Campaign". But unfortunately on scientific grounds we are still lacking absolute evidence for Rapid Response Team. Here we will give synopsis of 2 conflicting studies. Unfortunately again, its like comparing oranges to apples as second study comprised only of surgical patients.
1. MERIT STUDY: 23 hospitals in Australia were randomized to continue functioning as usual (n=11) or to introduce a RRT/MET system (n=12). The RRT was called only to 30% of patients who fulfilled the calling criteria.
Was it just an over active issue or a manifestation of poor pre-training ?.
The outcomes (cardiac arrests, unplanned ICU admissions and unexpected deaths) were analyzed. And the final conclusion was: although the call to RRT/MET system (3·1 vs 8·7 per 1000 admissions) was greatly increased, but does not substantially affect the incidence of cardiac arrest (1·64 vs 1·31 per 1000 admissions; p=0·736), unplanned ICU admissions (4·68 vs 4·19 per 1000 admissions; p=0·599), or unexpected death (1·18 vs 1·06 per 1000 admissions; p=0·752).
2. Bellomo and colleague's trial - effect of MET on postoperative morbidity and mortality rates: In the control period, there were 336 adverse outcomes in 190 patients, which decreased to 136 in 105 patients during the intervention period (relative risk reduction, 57.8%; p < .0001). These changes were due to significant decreases in the number of cases of respiratory failure, stroke, severe sepsis and acute renal failure (requiring renal replacement therapy). Emergency intensive care unit admissions were also reduced as well as postoperative deaths. Duration of hospital stay after major surgery decreased from a mean of 23.8 days to 19.8 days.
IHI's Rapid Response Team - getting started kit
SCCM's RRT/ MET forum
References: first popup overwrites second popup
1. Introduction of the medical emergency team (MET) system: a cluster-randomised controlled trial, MERIT study - The Lancet 2005; 365:2091-2097 - abstract available with free registration
2. Prospective controlled trial of effect of medical emergency team on postoperative morbidity and mortality rates - Critical Care Medicine: Volume 32(4) April 2004 pp 916-921
Sunday, March 19, 2006
Atenolol & Renal Failure
One must use caution while prescribing atenolol to patients with renal insufficiency. The elimination half-life of atenolol is extensively prolonged in patient with renal failure. The normal half life of atenolol is 6 to 7 hours; however, in renal failure patients the half-life may be extended to more than 100 hours 2.The recommended dosage are following:
CrCl 35 mL/min or greater - normal dosing
CrCl 15 - 35 mL/min - MAX. dose 50 mg orally QD
CrCl less than 15 mL/min - MAX. dose 25 mg orally QD
Hemodialysis: 25-50 mg orally after each dialysis session.
Treatment of atenolol overdose in a patient with renal failure is recommended with serial hemodialysis and charcoal hemoperfusion 3.
On the contrary, metoprolol is extensively metabolized via the hepatic system.
1.Atenolol-DOSAGE AND ADMINISTRATION - rxlist.com
2.Atenolol kinetics in renal failure - Clin Pharmacol Ther. 1980 Sep;28(3):302-9
3. Treatment of atenolol overdose in a patient with renal failure using serial hemodialysis and hemoperfusion and associated echocardiographic findings Vet Hum Toxicol. 2000 Aug;42(4):224-5.
Sign-out Mortality !
Regular evening work (sign-out) round is an integral part of all tertiary/teaching ICUs in USA but unfortunately as we transit to private practice or community hospital enviroment, we tend to loose this wonderful tradition. Ever thought about poor sign-out to your colleague as a patient safety issue?. A group pf physicians from Chicago have published their study in Quality and Safety in Health Care.
26 interns caring for 82 patients were interviewed after receiving sign-out from another intern. 25 discrete incidents, all the result of communication failures during the preceding patient sign-out, and 21 worst events were described. Omitted content (such as medications, active problems, pending tests) or failure-prone communication processes (such as lack of face-to-face discussion) emerged as major categories of failed communication. Ever think of sign-out as a procedure?
Read interesting article related to this topic Glucose Roller Coaster with sample signout sheet at the AHRQ WebM&M website, from Bradley A. Sharpe, MD, University of California, San Francisco .
Communication failures in patient sign-out and suggestions for improvement: a critical incident analysis - Quality and Safety in Health Care 2005;14:401-407
Saturday, March 18, 2006
Diagnostic crireia of Retinoic acid Syndrome
Retinoic acid syndrome is the major side effect of tretinoin therapy ATRA (all-trans retinoic acid) in patients with acute promyelocytic leukaemia (APL). It occurs in about quarter of patients with treatment. It has been suggested that 3 out of the following 7 signs and symptoms should be present to label patients as having Retinoic acid syndrome while getting ATRA and in the absence of other causes like sepsis 1, 2.
2. Weight Gain
3. Respiratory distress
4. Pulmonary infiltrates
5. Pleural or pericadial effusion
7. Renal failure
Read: Retinoic Acid Syndrome: A Case Report and Review from The Internet Journal of Oncology. 2005. Volume 2 Number 2.
Bonus Pearl: Acute colonic pseudo-obstruction (Ogilvie's syndrome) is one of the another complication may happen during induction treatment with chemotherapy and all-trans-retinoic acid for acute promyelocytic leukemia 3.
Reference: (click to get article )
1. Incidence, Clinical Features, and Outcome of All Trans-Retinoic Acid Syndrome in 413 Cases of Newly Diagnosed Acute Promyelocytic Leukemia - Blood, Vol. 92 No. 8 (October 15), 1998: pp. 2712-2718
2. The "retinoic acid syndrome" in acute promyelocytic leukemia - Ann Intern Med. 1992 Aug 15;117(4):292-6.
3. Acute colonic pseudo-obstruction (Ogilvie's syndrome) during induction treatment with chemotherapy and all-trans-retinoic acid for acute promyelocytic leukemia - Am J Hematol.1995 May;49(1):97-8.
Friday, March 17, 2006
ICU anemia score
A group of physicians from The CRISMA Laboratory (Clinical Research, Investigation, and Systems Modeling of Acute Illness), Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, USA have developed this ICU anemia score, which can be calculated at 6 hours after admission to intensive care unit.
6 points if......Lactate more than 1.5 mg/dl
5 points if......Inotropic support
11 points if....Surgical patient
5 points if......Non-emergent surgery
3 points to.....Each g/dl of hemoglobin less than 14 g/dl
Risk of anemia starts rising beyond 12 points and goes up. Also, points can be plotted on the probability of anemia graph (figure 3 in reference).
Clinical Significance: Once risk of anemia is determined, earlier and more appropriate use of blood transfusion-sparing strategies can be applied such as erythropoietin.
Note: Its hard to fully grasp the idea in nut-shell and icuroom.net editors strongly recommend to read article fully as available free by clicking on reference.
Predicting late anemia in critical illness - Eric B Milbrandt,Gilles Clermont, Javier Martinez, Alex Kersten, Malik T Rahim and Derek C Angus - The CRISMA Laboratory (Clinical Research, Investigation, and Systems Modeling of Acute Illness), Department of Critical Care Medicine, University of Pittsburgh School of Medicine, 3550 Terrace Street, Pittsburgh, PA 15261, USA -Critical Care 2006, 10:R39
Thursday, March 16, 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/.02 and continue to escalate till desired control achieved. Control can be made tighter as needed with blood glucose level at given point. 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).
Wednesday, March 15, 2006
procalcitonin (PCT) has been claimed to be one of the most specific marker for sepsis/infection. It increases with high specificity in response to clinically relevant bacterial infections and sepsis. PCT has a fast kinetic and can be measured as soon as 3-4 hours after infection. Normal PCT value is less than 0.5 ng/ml and its level in sepsis is generally greater than 1-2 ng/ml and often between 10 and 1000 ng/ml. As the septic infection resolves, PCT reliably returns to low values with a half-life of 24 hours and here the actual value lies to follow the trend to see response to treatment. Another cost-effective advantage is to limit the days of antibiotics depending on resolving trend of PCT value.
In a recent study it was found that PCT values should be determine differently between medical and surgical patients . In surgical patients, the best diagnostic cutoff value was 9.70 ng/mL and in medical patients, the best diagnostic cutoff value was 1.00 ng/mL. It was concluded by authors that: Procalcitonin was a reliable early prognostic marker in medical but not in surgical patients with septic shock. (see reference # 2). Its real value still needs to be tested in a major trial as we have other inexpensive and generic tests available like WBC count, Lactic acid level, CRP etc.
Official web site procalcitonin.com
Previous Related Pearl: C-Reactive Protein (CRP) - marker of mortality in ICU ?
References: (click to get abstract - second popup overwrites first popup)
1. Diagnostic and prognostic value of procalcitonin in patients with septic shock. Critical Care Medicine. 32(5):1166-1169, May 2004.
2. Differential diagnostic value of procalcitonin in surgical and medical patients with septic shock. Critical Care Medicine. 34(1):102-107, January 2006.
Tuesday, March 14, 2006
Hypoglycemia risk factors in ICU
We hear a lot about effects of hyperglycemia in ICU but on the other end of spectrum, hypoglycemia could be actually more or atleast equally disastrous. Dr. Vriesendorp and coll. from Amsterdam, The Netherlands looked into record of 2,272 patients and found that 156 patients (6.9%) experienced at least one episode of hypoglycemia (glucose value less than 45 mg/dL). They found following risk factors for hypoglycemia in ICU.
- CVVHD with bicarbonate-based substitution fluid,
- Decrease of nutrition without adjustment for insulin infusion,
- History of diabetes mellitus,
- Insulin use,
- Inotropic support and
- Simultaneous octreotide and insulin use.
Interestingly, Gastric residual during enteral nutrition without adjusting insulin infusion, liver failure, continuous venovenous hemofiltration with lactate-based substitution fluid, diminished glomerular filtration rate, dose diminishment of glucocorticoids or catecholamines, and use of β-blocking agents were not associated with hypoglycemia.
Related Previous Pearl:
Reference: (click to get abstract)
Predisposing factors for hypoglycemia in the intensive care unit - Critical Care Medicine. 34(1):96-101, January 2006.
Monday, March 13, 2006
Introducing Resident ICU Course
Under the banner of Society of Critical Care Medicine 23 lectures (power point) related to Critical Care Medicine have been uploaded at site
It includes essential topics like Airway Management, Mechanical Ventilation, Arterial Blood Gas Interpretation, Endocrine Issues in Critical Illness, Neurologic and Neurosurgical Emergencies, Acute Kidney Dysfunction, Nutritional Support in the ICU etc.Site is free but requires registration. It involves pre and end of rotation online tests with case-scenario based questions. This web-based curriculum has been developed by the Graduate and Resident Education Committee, a committee of the Society of Critical Care Medicine. These presentations have been authored by experts in the corresponding fields and can be downloaded/saved to computer.Highly recommended for medical residents.
*Site has 2 arms - Adult and Pediatric
Sunday, March 12, 2006
Power of Vitamin K
Q; In patients with Warfarin (Coumadin) , any dose more than ______ mg of Vitamin K will make reanticoagulation difficult.
Ans; 1 mg.
Previous Related Pearl: 7 Pearls of Vitamin K (phytonadione)
Care of Patients Receiving Long-Term Anticoagulant Therapy - S Schulman, - Volume 349:675-683, Aug 14 '03
Saturday, March 11, 2006
Triad of HELLP Syndrome
HELLP syndrome is a unique variant of preeclampsia and may manifest even before clinical signs of preeclampsia. Triad or criteria and term "HELLP" syndrome was first designated by Louis Weinstein, M.D. in 1982 in American Journal of Obstet. Gynecol. 1, and is as follows:
1. Hemolysis: Abnormal blood smear - Elevated Bilirubin >1.2 mg/dl
2. Elevated liver enzymes - with SGOT >72 UI / L (but has been mentioned as low as 40) and LDH >600 UI/L
3. Low Platelets: Less than 100. Please note that platelet's cutoff of 100 is debatable and another classification for this syndrome called Mississippi Classification used level less than 150. Read reference # 2 which may need subscription.
See impressive slide presentation here on HELLP Syndrome from JOHN ESSIEN M.D. and coll. from HOSPITAL GINECOBSTÉTRICO PROVINCIAL, CAMAGÜEY., CUBA - (its a power point presentation)
Previous related pearl: IV Magnesium (Mg) infusion
1.Syndrome of hemolysis, elevated liver enzymes, and low platelet count: a severe consequence of hypertension in pregnancy. Weinstein L. Am J Obstet Gynecol.1982 Jan 15;142(2):159-67
2. Prevention of Eclampsia - letters to editor, NEJM, May 23, 2003, Volume 348:2154-2155
Friday, March 10, 2006
Q: What is Frog sign?
A: In Paroxysmal Supra-Ventricular Tachycardia (PSVT) a rapid and regular bulging seen in the neck. These are actually prominent jugular venous A waves due to atrial contraction against the closed tricuspid valve, and termed as "frog sign".
1. Brief report: the hemodynamic mechanism of pounding in the neck in atrioventricular nodal reentrant tachycardia - N Engl J Med. 1992 Sep 10;327(11):772-4.
2. Evaluation of Patients with Palpitations - NEJM, May, 1998, Volume 338:1369-1373
Thursday, March 09, 2006
Evidence-based recommendations for Severe Acute Pancreatitis (SAP)
An international consensus conference was held in April 2004 to develop guidelines for the management of the critically ill patient with SAP and published in December 2004 issue of Critical Care Medicine. 23 evidence-based recommendations were developed by a jury of ten persons representing surgery, internal medicine, and critical care after conferring with experts and reviewing the pertinent literature. We are pening here few most important recommendations but full article can be pulled from reference below.
* Critically ill patients with pancreatitis be cared for by an intensivist-led multidisciplinary team with ready access to physicians skilled in endoscopy, endoscopic retrograde cholangiopancreatography (ERCP), surgery, and interventional radiology.
* Followup CT to identify local complications be delayed for 48-72 hrs when possible, as necrosis might not be visualized earlier.
* Recommendation against the routine use of prophylactic systemic antibacterial or antifungal agents in patients with necrotizing pancreatitis.
* Enteral nutrition should be initiated after initial resuscitation. The jejunal route should be used if possible and parenteral nutrition only be used when attempts at enteral nutrition have failed after a 5- to 7-day trial and when used, parenteral nutrition should be enriched with glutamine.
* Sonographic- or CT-guided FNA with Gram stain and culture of pancreatic or peripancreatic tissue to discriminate between sterile and infected necrosis in patients with radiological evidence of pancreatic necrosis and clinical features consistent with infection and recommendation against debridement and/or drainage in patients with sterile necrosis.
* Pancreatic debridement or drainage in patients with infected pancreatic necrosis and/or abscess confirmed by radiological evidence of gas or results of FNA. The gold standard for achieving this goal is open operative debridement. If possible, operative necrosectomy and/or drainage be delayed at least 2-3 wks to allow for demarcation of the necrotic pancreas.
* In acute pancreatitis due to suspected or confirmed gallstones, urgent ERCP should be performed within 72 hrs of onset of symptoms.
* Use of early volume resuscitation and lung-protective ventilation strategies for patients with acute lung injury.
* In SAP with severe sepsis careful consideration be used before the administration of rh-APC based on the theoretical but unproven concern of retroperitoneal hemorrhage.
Management of the critically ill patient with severe acute pancreatitis - Critical Care Medicine: Volume 32(12) December 2004 pp 2524-2536 . Sponsored by the American Thoracic (ATS), the European Respiratory Society (ERS), the European Society of Intensive Care Medicine (ESICM), the Society of Critical Care Medicine (SCCM) and the Société de Réanimation de Langue Française (SRLF).
Wednesday, March 08, 2006
Chest tube (tube thoracostomy) with seldinger technique - underutilize technique?
Cannulation of pleural space was first described by Hippocrates (460 B.C) and in modern medicine about 140 years ago by Hillier 1. Chest tube insertion gained huge respect during 2 world wars as a life saving procedure. Over last few decades technique remain mostly unchanged with insertion either with help of trocar or with direct insertion with scalpel/clamp and finger opening of pleural space. In recent years insertion of chest tube with seldinger technique (over guide wire) has been described but still remain less popular, although, it has significant advantages over traditional method as it is less painful, easy to insert, can be master easily and ? less prone to infection. The only disadvantage is inability to 'feel' pleural space. On literature search we were unable to find any head to head study comparing seldinger technique with operative technique. There is only one attempt earlier to check literature (see reference # 2) and found that seldinger technique is no way inferior (or superior either) to traditional chest tube insertion.
Chest tubes are available for seldinger technique insertion upto 36 f size. See details here from Cook (maker of Thal-Quick chest tubes).
Isn't it time to graduate to seldinger technique for chest tubes as we did for central venous catheters from cut-downs? All comments are welcome.
References: (click to get article)
1. Chest tube - int.med.utah.edu
2. Seldinger technique chest drains and complication rate - Emerg Med J 2003; 20:169-170
Tuesday, March 07, 2006
Some facts about FFP
Several plasma alternatives can be used for coagulation factor replacement. The most commonly used plasma component is Fresh Frozen Plasma (FFP). One unit of FFP or thawed plasma is the plasma taken from a unit of whole blood. It is frozen within eight hours of collection. FFP contains all coagulation factors in normal concentrations. Plasma may be stored for as long as I year at -18° C or colder. Thawed plasma may be transfused up to 5 days after thawing and contains slightly decreased levels of Factor V and decreased Factor VIII levels. Plasma is free of red blood cells, leukocytes and platelets. One unit is approximately 200-250mL and must be ABO compatible. Rh factor need not be considered. Since there are no viable leukocytes, plasma does not carry a risk of CMV transmission or Graft Vs. Host Disease (GVHD).
The dose of FFP depends on the clinical situation and the underlying disease process. Only 15% - 35% of normal levels of factors are required to maintain normal hemostasis. When FFP is given for coagulation factor replacement, the dose is 10-20 ml/Kg (4-6 units in an adult). This dose would be expected to increase the level of coagulation factors by 20% immediately after infusion. In a 70 kg Patient: 1 Unit Plasma increases most factors ~2.5%. 4 Units Plasma increase most factors ~10%.
FFP may be rapidly transfused over 20-30 minutes. The rate is mainly limited by the patient’s ability to tolerate the volume. Allergic reactions occur in approximately 1% of patients receiving FFP. The reactions are usually mild consisting of an urticarial rash (hives) and pruritus. FFP has not been associated with transmission of CMV or HTLV-I, II since these viruses are exclusively white cell associated and plasma is virtually acellular.
Related previous Pearl : How much FFP?
Also for your file:
1. Guidelines for the use of Fresh Frozen Plasma, cryoprecipitate and cryosupernatant from British Committee for Standards in Haematology, Blood Transfusion Task Force, British Society of Haematology - British Journal of Haematology 2004; 126, 11-28
2. Australian National Guidelines on FFP and Cryoprecipitate
Monday, March 06, 2006
BEDSIDE CREATININE CLEARENCE
The most sensitive measure of changing renal function is not the serum creatinine, but the creatinine clearance. Serum creatinine underestimates the degree of renal insufficiency in many situations like :
- Anyone with a renal insufficiency but a GFR more than 50 ml/min, because serum creatinine does not start to rise until GFR falls below 50 ml/min
- Cachexia – because creatinine production is so low, serum creatinine may rise only when GFR falls below 25 ml/min
- After surgery in patients who have received a lot of fluids. A 10 – 15% increase in total body water results in dilution of serum creatinine by an equivalent amount.
The most useful means of estimating GFR at bedside is a two-hour creatinine clearance. There is nothing about clearance that mandates a 24-hour urine collection, particularly when there is a Foley’s catheter in place, which largely eliminates error due to urine retention. As long as the collection is carefully timed and the urine flow is more than 30 ml/hr, a collection as short as 2-hour will give reasonable data.
Creatinine clearance may be calculated simply by UV/P
where U is the urine creatinine in mg/dl,
V is the urine flow rate in ml/min and
P is the serum creatinine in mg/dl.
The term ‘UV’ i.e is urine creatinine times urine flow rate, represents the creatinine excretion rate. It is THIS that changes rapidly with changing GFR.
1. Clinical Practice Guidelines for Chronic Kidney Disease: Evaluation Classification and Stratification - National Kidney Foundation / Kidney Disease Outcomes Quality Initiative.
2. ESTIMATION OF CREATININE CLEARANCE IN PATIENTS WITH UNSTABLE RENAL FUNCTION (Dr. Roger Jelliffe - School of Medicine at the University of Southern California).
Sunday, March 05, 2006
Sunday Basic !
Some lessons (not all) learnt in medical school are worth remembering every moment at bedside. For intensivist, following simple fact carries huge bedside implications.
"Left ventricle is perfused most actively in early diastole, not when aortic pressure is at its maximum but when myocardial pressures are least".
Who knows the dilemma of intensivist better than himself while trying to find that fine line between volume, pressors, hear rate and blood pressure.
Related: Cardiac angioplasty and stent placement video (Dr. Tyrus Frerking - Mount Carmel health - Ohio) - needs window media player.
Saturday, March 04, 2006
Saturday March 4, 2006
Prayer Sign - If patient shows inability to place palms flat together, it suggests difficult intubation. It is a reflection of generalised joint and cartilage immobility and tight waxy skin, particularly in diabetic patients. About 33% of diabetic patients are prone to difficult intubations. One study from Istanbul, Turkey compared 80 diabetic patients (D) with 80 non-diabetic patients (ND) undergoing elective surgery under general anaesthesia. The incidence of difficult laryngoscopy was 18.75% in Group D and 2.5% in Group ND. The incidence of the prayer sign was 31.25% in Group D and 13.75% in Group ND.
Another version of prayer sign is "palm print" method in which grading of the ink impression made by the palm of the hand has been proposed as a means of screening diabetic patients in whom tracheal intubation may prove difficult. In one study, it was found to be superior to 3 other indices - Mallampati classification, thyromental distance and head extension.
References: (second popup overwrites first popup)
1. Relationship of difficult laryngoscopy to long-term non-insulin-dependent diabetes and hand abnormality detected using the ‘prayer sign’ - British Journal of Anaesthesia, 2003, Vol. 91, No. 1 159-160
2. The palm print as a sensitive predictor of difficult laryngoscopy in diabetics - Acta Anaesthesiol Scand. 1998 Feb;42(2):199-203.
Friday, March 03, 2006
4 criteria of Peripartum Cardiomyopathy (PPCM)
Contributed by: Saadia Faiz M.D., senior Pulmonary and Critical Care fellow, University of Texas at Houston Program.
Peripartum cardiomyopathy is a deadly disease with mortality described upto 56%. Relationship of heart failure with pregnancy was first described in medical literature about 135 years ago by Virchow & Porack . In 1937 it was recognised as distinct entity with dilated cardiomyopathy by Gouley. 35 years ago Demakis and Rahimtoola defined PPCM on the basis of 4 criteria. It was modified by National Heart, Lung, and Blood Institute and Office of Rare Diseases (National Institutes of Health) Workshop in April 1997.
1. Heart failure within the last month of pregnancy or 5 months postpartum.
2. Absence of preexisting heart disease.
3. No determinable etiology and
4. Strict echocardiographic criteria of left ventricular dysfunction: Ejection fraction less than 45%, or M-mode fractional shortening less than 30%, or both, and end-diastolic dimension more than 2.7 cm/m2 body surface area.
Related: Click here to read review article on recognition and management of maternal cardiac disease in pregnancy from British Journal of Anaesthesia (Reference: 2004 93(3):428-439)
References: (second popup overwrites first popup)
1. Peripartum cardiomyopathy. Demakis JG, Rahimtoola SH. Circulation. 1971 Nov;44(5):964-8
2. Peripartum Cardiomyopathy - National Heart, Lung, and Blood Institute and Office of Rare Diseases (National Institutes of Health) Workshop Recommendations and Review -JAMA. 2000;283:1183-1188. Full text available with free registration.
3. Peripartum Cardiomyopathy - Cardiology in Review. 14(1):35-42, January/February 2006.
Thursday, March 02, 2006
How much FFP?
Dr. Sam Schulman from Karolinska Hospital, Stockholm, Sweden wrote an excellent review on "Care of Patients Receiving Long-Term Anticoagulant Therapy" in August 14, 2003 issue of NEJM 1. Part of article suggest formula for amount of FFP (Fresh Frozen Plasma) to correct INR upto desired level in a bleeding patient from over-anticoagulation.
Amount of FFP needed(ml) =
(target level as percentage - present level as percentage) x Wt.(kg)
The "percentage" is prothrombin complex, expressed as a percentage of normal plasma, corresponds to the mean level of the vitamin K–dependent coagulation factors. It can be compute easily with following table:
INR 1 = 100 (%)
INR 1.4 - 1.6 = 40
INR 1.7 - 1.8 = 30
INR 1.9 - 2.1 = 25
INR 2.2 - 2.5 = 20
INR 2.6 - 3.2 = 15
INR 4.0 - 4.9 = 10
INR > 5 = 5 (%)
In a 70 kg patient bleeding with INR of 7.5 and if our target is to bring INR down to 1.4, using above table:
Total FFP needed = (40 - 5) x 70 = 2450 ml
(One unit FFP usually contains 200-250 ml of FFP).
Care of Patients Receiving Long-Term Anticoagulant Therapy - Sam Schulman, M.D. - Volume 349:675-683, August 14, 2003