Prone positioning is back!

May 20, 2013 issue of NEJM has newest study published on Prone Positioning in Severe Acute Respiratory Distress Syndrome. Many previous trials involving patients with the acute respiratory distress syndrome (ARDS) have failed to show a beneficial effect of prone positioning during mechanical ventilatory support on outcomes. 

In this multicenter, prospective, randomized, controlled trial, of 466 patients with severe ARDS, patients were assigned to either go prone-positioning sessions of at least 16 hours or to be left in the supine position.

Severe ARDS was defined P/F ratio less than 150 mm Hg, with an FiO2 of at least 0.6, a PEEP of at least 5 cm of water, and a tidal volume close to 6 ml per kilogram of predicted body weight. 

The primary outcome was the proportion of patients who died from any cause within 28 days after inclusion.

A total of 237 patients were assigned to the prone group, and 229 patients were assigned to the supine group. 

• The 28-day mortality was 16.0% in the prone group and 32.8% in the supine group (P less than 0.001).
• The hazard ratio for death with prone positioning was 0.39 (95% confidence interval [CI], 0.25 to 0.63).
• Unadjusted 90-day mortality was 23.6% in the prone group versus 41.0% in the supine group (P less than 0.001), with a hazard ratio of 0.44 (95% CI, 0.29 to 0.67).
• The incidence of complications did not differ significantly between the groups, except for the incidence of cardiac arrests, which was higher in the supine group.
  
  
  Study concluded that In patients with severe ARDS, early application of prolonged prone-positioning sessions significantly decreased 28-day and 90-day mortality.

Guérin C, Reignier J, Richard J-C, et al. Prone positioning in severe acute respiratory distress syndrome. N Engl J Med 2013.

http://www.nejm.org/doi/full/10.1056/NEJMoa1214103

Pigtail Catheter insertion

 If video doesn't work, click or cut n paste 

http://youtu.be/nrxuZwFpigI

Hyponatremia and non-cardiogenic pulmonary edema

 

 

One less paid attention during management of hyponatremia is to non-cardiogenic pulmonary edema, which can develop at Sodium level below 121 ± 3 mmol/L. In these settings usually EKG and echocardiograms are normal. CXR shows pulmonary edema with a normal heart. Also, cardiac enzymes are normal, and pulmonary wedge pressure not elevated. Cerebral edema may simultaneously may be present. Situation is usually reversible with reversal of hyponatremia.

 

 

 

Reference:

 

 

1. J. Carlos Ayus, MD; Joseph Varon, MD; and Allen I. Arieff, MD Hyponatremia, Cerebral Edema, and Noncardiogenic Pulmonary Edema in Marathon Runners, Ann Intern Med. 2000;132(9):711-714

 

2. Ayus JC, Arieff AI., Pulmonary complications of hyponatremic encephalopathy. Noncardiogenic pulmonary edema and hypercapnic respiratory failure., Chest. 1995 Feb;107(2):517-21.

Q: Which diuretic can have antimineralocorticoids effects?

Answer: Spironolactone

Spironolactone decreases the effects of mineralocorticoids including aldosterone and corticosterone by competing for intracellular mineralocorticoid receptors in the cortical collecting duct. 

On Relative Bradycardia!

Appropriate temperature–pulse relationships
Temperature	Beats/min
41.1 °f.f.s.C (106 °F)	150
40.6 °f.f.s.C (105 F)	140
40.7 °f.f.s.C (104 F)	130
39.4 °f.f.s.C (103 F)	120
38.9 °f.f.s.C (102 F)	120
38.3 °f.f.s.C (101 F)	110

Patient must be an adult, i.e. ≥ 13 years, with temperature ≥ 102 °F. Pulse must be taken simultaneously with the temperature elevation. Patient should be in Normal Sinus Rhythm without arrhythmia, second/third- degree heart block or pacemaker-induced rhythm. Patient must not be on β-blocker medication.

Fidaxomicin - a new kid in the block to treat C.Diff.

Fidaxomicin is a narrow spectrum macrocyclic non-systemic antibiotic drugs. It is bactericidal, and causes selective eradication of pathogenic Clostridium difficile  with minimal disruption of the other bacteria that make up the normal, healthy intestinal flora. As evident, the maintenance of normal physiological conditions in the colon is the best defense against the probability of Clostridium difficile infection recurrence.

Dose is 200 mg tablet every 12 hours for the duration of 10 days. 

 On dangers of Rectal Tubes
Abstract

The management of fecal incontinence is a struggle to maintain patient hygiene and limit the transmission of nosocomial infections. Intrarectal devices that cause diversion and collection of the fecal stream have been used with increasing frequency. This method can effectively control patient waste if used in an appropriate setting.

We examine a series of 3 patients in whom rectal trauma resulting in life-threatening hemorrhage was associated with use of the ConvaTec Flexi-Seal fecal management system.

In 2 patients there was a history of traumatic removal, and the third developed a rectal pressure ulcer associated with use of this device. All 3 patients required surgical or endoscopic intervention to achieve hemostasis.

Although effective, the Flexi-Seal fecal management system should be used with caution to avoid rectal trauma. Injury is most likely to occur because of traumatic removal or rectal ulceration secondary to pressure necrosis.

Reference:

Sparks D and coll.  - Rectal trauma and associated hemorrhage with the use of the ConvaTec Flexi-Seal fecal management system: report of 3 cases. , Dis Colon Rectum. - 2010 Mar;53(3):346-9

Q: Initiation of ACE-inhibitors and ARBs (angiotensin receptor blockers), may cause approximately what level of increment in baseline creatinine - and it should be OK!?

Answer:  ACEIs and ARBs could result in a 25% "permissible" increment of baseline serum creatinine and should not become an indication to stop these families of drugs.

But, a persistent upward trend of serum creatinine while on ACEIs and ARBs should be an alert to the possibility of bilateral renal artery stenosis or renal artery stenosis in solitary functioning kidney.

 

 

Q: 44 year obese male admitted with PE is now on Heparin and transitioniing to warfarin therapy. On 9th day of treatment, patient is diagnosed with HIT (Heparin induced Thrombocytopenia) with platelet count of 72. INR is reported to be 2.9. What would be your next step beside stopping Heparin?

Answer: Stop Warfarin and  reverse Warfarin effect with Vitamin K.

There is a very high risk of warfarin necrosis in people with HIT who have low platelet counts. Warfarin, should not be used in HIT until the platelet count is at least 150 x 10^9/L. Warfarin necrosis is marked by skin gangrenes. If the patient was receiving warfarin at the time when HIT is diagnosed, the activity of warfarin should be reversed with vitamin K.

Another important decision to make is need of use of 'direct thrombin inhibitors'.

Metoprolol and CNS effect

 One less know side effect of Metoprolol (Lopressor) is CNS effect, which may be of importance in ICU. Lopressor's CNS effect is dose dependent. It has high penetration across the blood brain barrier due to its lipophilic nature. In return, it may cause sleep disturbances, vivid dreams, nightmares, depression, and vision problems.

Q: 28 year old male is transferred from floor to ICU. Patient was admitted to floor 6 days ago with acute exacerbation of Multiple Sclerosis (MS). Patient did not show much improvement after high dose of steroid treatment. What could be your next step?



Answer:  Plasmapheresis

High doses of steroids (like 1000 mg of solumedrol) remained the mainstay of therapy for acute relapses in MS. Please note oral and IV corticosteroids have a similar efficacy.

Severe attacks of MS which do not respond to steroids are recommended to be treated by plasmapheresis.



References:

1. Compston A, Coles A (October 2008). "Multiple sclerosis". Lancet 372 (9648): 1502–17.

2. Multiple sclerosis : national clinical guideline for diagnosis and management in primary and secondary care -  London: Royal College of Physicians. 2004. pp. 54–57.

 - (http://www.ncbi.nlm.nih.gov/books/NBK48919/pdf/TOC.pdf)

Q: 28 year old female, admitted to ICU with Urosepsis. Patient routine screening becomes positive for pregnancy. Patient was unaware of it. Her list of medications include methimazole for her hyperthyroidism. What would be your next step?


Answer:

If pregnancy occurs while taking methimazole, switching to propylthiouracil (PTU) is suggested, particularly in first trimester.

Both PTU and methimazole are classified as Drug Class D in pregnancy. PTU is preferred over methimazole in the first trimester of pregnancy. In the second and third trimester, methimazole is preferred.



References:

1. Bahn RS, Burch HS, Cooper DS, et al. (July 2009). The Role of Propylthiouracil in the Management of Graves' Disease in Adults: report of a meeting jointly sponsored by the American Thyroid Association and the Food and Drug Administration . Thyroid 19 (7): 673–4.

2. Abalovich M, Amino N, Barbour LA, et al. (August 2007). Management of thyroid dysfunction during pregnancy and postpartum: an Endocrine Society Clinical Practice Guideline . J. Clin. Endocrinol. Metab. 92 (8 Suppl): S1–47

Q: In Tension pneumothorax, atelectasis, pulmonary edema, and pneumonia (Choose one)

A) Both static and dynamic compliance fall

B) Only dynamic compliance fall

C) Only static compliance fall

D) Both static and dynamic compliance remain unchanged

Answer is A

Formulae for compliances are as follows

Static compliance is based on plateau pressure (no air is flowing)

Cstat = Vt/(Pplat - PEEP)

Dynamic compliance is based on peak pressure (air is flowing)

Cdyn = Vt/(Ppeak - PEEP)

In tension pneumothorax, atelectasis, pulmonary edema, and pneumonia both peak and plateau pressures rise and so cause both compliances to fall.

kcentra

The FDA has approved the use of Kcentra for the urgent reversal of vitamin K antagonist anticoagulation in adults with acute major bleeding.

Unlike plasma, Kcentra can be administered rapidly because it does not require thawing, though Kcentra is made from the pooled plasma of healthy donors and is processed to minimize risk for transmitting viral and other diseases, according to the FDA press release. Kcentra (CSL Behring) is used in conjunction with the administration of vitamin K.

Study has demonstrated that Kcentra was similar to plasma in terms of stopping acute major bleeding.

Another advantage is, Kcentra is administered in a significantly lower volume than plasma at recommended doses, providing an alternative for those patients who may not tolerate the volume of plasma.

As expected, Kcentra is associated with some risk of arterial and venous thromboembolic complications.

See full prescribing info here

Q: In which organ dysfunction, Eptifibatide (Integrilin) should be used with caution?

Answer: Renal Dysfunction.

Eptifibatide (Integrilin)is an antiplatelet drug of the glycoprotein IIb/IIIa inhibitor class used in Acute Coronary Syndome and in patients undergoing Percutaneous Coronary Intervention (PCI).

Eptifibatide gets eliminated via renal route. Bolus dose remains same (180 µg/kg) but continuous infusion should be curtail back to half dose i.e. 1.0 µg/kg/min.

Patients undergoing, Percutaneous Coronary Intervention (PCI) - a second bolus dose of 180-µg/kg is given after 10 minutes of the first bolus.

Q; What is the mechanism of action, causing Hyperkalemia with Heparin therapy?

Answer: 5 to 10% of patients receiving heparin develops hyperkalemia. It is the result of heparin-induced aldosterone suppression.

Steroids Conversion Data

Glucocorticoid Approximate Equivalent dose (mg) Half-life (Biologic) hours Short-Acting Cortisone 25 8-12 Hydrocortisone 20 8-12 Intermediate-Acting Methylprednisolone 4 18-36 Prednisolone 5 18-36 Prednisone 5 18-36 Triamcinolone 4 18-36 Long-Acting Betamethasone 0.6 - 0.75 36-54 Dexamethasone 0.75 36-54

Q: What is the role of steroids in Thyroid storm?

Answer:

Glucocorticoids prevents further Thyroid Hormone secretion and peripheral conversion of T4 to T3. Interestingly, iodinated radiocontrast dyes can be use for same purpose.

Q: 58 year old male with IPF (interstitial Pulmonary fibrosis) became unstable and required intubation. "Swan" is floated with high pulmonary pressure. Nebulized Flolan (Epoprostenol) is initiated at room temperature. How frequent Nebulizer, infusion tubing and connections should be changed?

A) Once a day

B) Once a week

C) Every 8 hours

D) Every 72 hours

E) There is no need to change

Answer: C

Flolan for nebulized delivery must be reconstituted with glycine and is usually not compatible with any other solution. Glycine is sticky and viscous and also needs to be shielded from light. It is recommended to keep reconstituted solution cold with icepacks during administration (around 2-8 degrees C) as Flolan is stable for 8 hrs at room temp., and 24 hours if refrigerated. Nebulizer, infusion tubing and connections should be changed every 24 hrs (refrigerated) or every 8 hrs (unrefrigerated) as drug expires.

Q: Which modality/drug is no more recommended for Asystole per 2010 ACLS guidelines?

A) Epinephrine

B) Atropine

C) Transcutaneous Pacemaker

D) Transvenous Pacemaker

E) Vasopressin

Answer: B

In ACLS, Atropine is no more recommended during Asystole/PEA. Routine use of atropine during PEA or asystole has not shown any therapeutic benefit.

Oxygen dissociation curve

If video is not visible click below

Here

http://youtu.be/HYbvwMSzqdY

Bedside caution on Thrombolytic therapy for central venous catheter occlusion

Thrombolytic agents successfully clear central venous catheter occlusions in most cases. (1).

Good practice is, once catheter function is restored, aspirate 4-5 mL of blood to remove thrombolytic  from catheter.




Reference / further reading:

1. Jacquelyn L. Baskin and col. - Thrombolytic therapy for central venous catheter occlusion - Haematologica. 2012 May; 97(5): 641–650.

 Skinfold vs Pneumothorax

"Absence of lung markings is not sufficient to make diagnosis of pneumothorax as lung may fold on itself"!

Click here* to have very informative slide presentation on recognising pneumothorax on CXR (from learningradiology.com)



*link: http://www.learningradiology.com/medstudents/recognizingseries/pneumothoraxflashpage.htm

An interesting way to find "optimum PEEP"

(Abstract)

This study was conducted to evaluate the effectiveness and safety of a practical protocol for titrating positive end-expiratory pressure (PEEP) involving recruitment maneuver (RM) and decremental PEEP.

Seventeen consecutive patients with acute lung injury who underwent PEEP titration were included in the analysis. After baseline ventilation, RM (continuous positive airway pressure, 35 cm H2O for 45 sec) was performed and PEEP was increased to 20 cmH2O or the highest PEEP guaranteeing the minimal tidal volume of 5 mL/kg. Then PEEP was decreased every 20 min in 2 cmH2O decrements.

The "optimal" PEEP was defined as the lowest PEEP attainable without causing a significant drop (>10%) in PaO2. The "optimal PEEP" was 14.5 +/- 3.8 cmH2O. PaO2 /FI O2 ratio was 154.8 +/- 63.3 mmHg at baseline and improved to 290.0 +/- 96.4 mmHg at highest PEEP and 302.7 +/- 94.2 mmHg at "optimal PEEP", both significantly higher than baseline (p<0.05).

Static compliance was significantly higher at "optimal" PEEP (27.2 +/- 10.4 mL/ cmH2O) compared to highest PEEP (22.3 +/- 7.7 mL/cmH2O) (p<0.05).

Three patients experienced transient hypotension and one patient experienced atrial premature contractions. No patient had gross barotrauma.

PEEP titration protocol involving RM and PEEP decrement was effective in improving oxygenation and was generally well-tolerated.



Reference:

Suh GY and col. - A practical protocol for titrating "optimal" PEEP in acute lung injury: recruitment maneuver and PEEP decrement..

J Korean Med Sci. 2003 Jun;18(3):349-54.

Q: What dose of Versed (midazolam) is optimum for antegrade amnesia?

Answer: About 0.05 – 0.1 mg/kg.

Reference:

Bulach R: Double-blind randomized controlled trial to determine extent of amnesia with midazolam given immediately before general anaesthesia. BJA 2005;94:300-5

Q: What is 80-10-10 distribution in brain?

Answer:

80% - Parenchyma

10% - Blood

10% - CSF

On IV acetaminophen

 "Compared to oral acetaminophen, IV acetaminophen achieves a rapid elevation in plasma concentration and higher peak levels. The IV form achieves plasma levels rarely achieved by similar oral doses of acetaminophen and produces 75% higher central nervous system (CNS) bioavailability compared to the oral form. The analgesic effect peaks within one hour and lasts for four to six hours." 

 Read full article here 

Darrell Harrington, MD 
Chief, Division of General Internal Medicine 
Harbor-UCLA Medical Center, Los Angeles 

 Source: Today's Hospitalist

Ultrasound Guidance for Thoracentesis 
 

 

Q: The Model for End-Stage Liver Disease, or MELD, is a scoring system for assessing the severity of chronic liver disease. Formula for MELD score is

MELD = 3.78[Ln serum bilirubin (mg/dL)] + 11.2[Ln INR] + 9.57[Ln serum creatinine (mg/dL)] + 6.43

If patient is already on Dialysis - what value of Creatinine is automatically substituted?

Answer: 4

In interpreting the MELD Score in hospitalized patients, the 3 month mortality is:

• 40 or more — 71.3% mortality
• 30–39 — 52.6% mortality
• 20–29 — 19.6% mortality
• 10–19 — 6.0% mortality
• <9 — 1.9% mortality

Q:  Cardiac output is the volume of blood being pumped by the heart, (left or right ventricle), in the time interval of ......

? (choose one)

A) One minute

B) One second

C) each beat

D) one respiratory cycle

Answer:  A) Per minute

Cardiac output is the volume of blood pumped by the heart per minute (mL blood/min). 

Cardiac output is a function of heart rate and stroke volume. The heart rate is simply the number of heart beats per minute. The stroke volume is the volume of blood, in milliliters (mL), pumped out of the heart with each beat. 

Cardiac Output in mL/min = heart rate (beats/min) X stroke volume (mL/beat)

An average resting cardiac output would be 5.6 L/min for a human male and 4.9 L/min for a female.