Q; 58 year old male with history of seizure is admitted to ICU with aspiration pneumonia requiring mechanical ventilation along with sedation and neuro-muscular blockade (NMB). Despite high dose of Nimbex (Cisatracurium) adequate NMB cannot be achieved. Which anti-seizure medicine may be interacting here?


Answer: Carbamazepine

Carbamazepine not only increases the clearance of cisatracurium, but also increases the resistance to the neuromuscular blocking effect of cisatracurium. Higher doses of cisatracurium may be required in patients on chronic carbamazepine therapy.

Rocuronium versus succinylcholine for rapid sequence induction intubation - Cochrane Review

In emergency situations some patients need a general anaesthetic with an endotracheal tube (tube to help them breathe). It is important to have fast acting medications to allow physicians to complete this procedure quickly and safely. Currently, the muscle relaxant medication most often used to accomplish this is succinylcholine. Succinylcholine is fast acting and lasts for only a few minutes which is very desirable in this setting. However, some patients cannot use this medication as it can cause serious salt imbalances or reactions, so an equally effective medication without these side effects is desired. This meta-analysis compared one possible alternative, rocuronium, for the quality of intubation conditions (the ease with which physicians can quickly and safely pass the endotracheal tube). In this review, we have combined the results of 37 studies, with a total of 2690 patients, which compared the effects of succinylcholine versus rocuronium on intubation conditions. We have found that rocuronium is less effective than succinylcholine for creating excellent intubation conditions. Rocuronium should therefore only be used as an alternative to succinylcholine when it is known that succinylcholine should not be used.

Click here to read review

Q: What advantage vasopressin has over other pressors particularly over epinephrine in code (ACLS) situation?

Answer: Most pressors including epinephrine loses much of its effectiveness in an acidotic plasma, but vasopressin demonstrates vasoconstricting efficacy even with severe acidosis. 



Wenzel V, Krismer AC, Arntz HR, Sitter H, Stadlbauer KH, Lindner KH. A comparison of vasopressin and epinephrine for out-of-hospital cardiopulmonary resuscitation. N Engl J Med. Jan 8 2004;350(2):105-13

On time lag between Precedex start and its effect

Loading dose of dexmedetomidine (precedex) is 1 mcg/kg loading dose, administered over 10 minutes, followed by a maintenance infusion of 0.2–0.7 mcg/kg/hour.

Important pearl to remember that despite with loading dose onset of sedation occurs after 10 to 15 minutes unlike instant sedation from propofol. If a loading dose is not used, time to onset of the sedative effect may be even more extended.

Q: In properly inserted IABP, on estimate how much improvement in renal perfusion is expected?

 

 

Answer: About 25%

 

Kidney blood flow can increase up to 25% due to increase in cardiac output. Decrease in urine output after insertion of IABP should raise the suspicion of juxta-renal balloon positioning.

Mediastinoscopy

Regarding Tigecycline in MDR Klebsiella and MDR Acinetobacter baumannii

Q: 72 year old NHR female is admitted to ICU with Urosepsis. Record shows previous cultures growing MDR Klebsiella resistant to most antibiotics. Pharmacy suggested Tigecycline?

Answer: Tigecycline is one of the very few antibiotics which are highly active against multidrug-resistant (MDR) Klebsiella pneumoniae and MDR Acinetobacter baumannii (MDR KP/AB) but may require high dosing for maximal therapeutic effectiveness. In such cases use an initial dose of 200 mg IV followed by 100 mg IV daily. If patient does not respond to this dose further higher dose can be use with initial dose of 400 mg IV followed by 200 mg IV daily.

Caution: Tigecycline should be given slowly in 250 - 500 ml bag to avoid GI symptoms.


Reference: Pharmacokinetic Considerations regarding Tigecycline for Multidrug-Resistant (MDR) Klebsiella pneumoniae or MDR Acinetobacter baumannii Urosepsis - Journal of Clinical Microbiology, May 2009, p. 1613, Vol. 47, No. 5

Tiger Tube

"......The recent development of ‘self-migrating’ Tiger tube is a promising alternative to endoscopically-placed nasojejunal tube. This eliminates the need of endoscopy with its costs and logistic difficulties. The aggressive approach to commence EN would improve outcome in critically ill patients and avoid complications associated with PN. Bedside clinicians can pass the tube into the stomach (which takes around 5-10 minutes) and then wait for the tube to migrate into the jejunum over the next 6-12 hours. This simple procedure potentially reduces the financial and manpower resources implicated in managing critically ill patients. Since it may lower the rate of regurgitation and aspiration, the incidence of ventilator-associated pneumonia can be potentially reduced".

Read case report and discussion here

(Enteral Nutrition In Intensive Care: ‘Tiger Tube’ – For Small Bowel Feeding In Acute Pancreatitis. Case Report - Mohd Basri bin Mat Nor. Department of Anaesthesiology and Intensive Care, Kulliyyah of Medicine, International Islamic University Malaysia.)

Ultrasound for subclavian central lines (CVC)

Ultrasound guided Internal Jugular CVC is now pretty much standard but see this study published this month in CCM Journal 1.

463 mechanically ventilated patients were compared - the ultrasound-guided subclavian vein cannulation (200 patients) vs. the landmark method (201 patients) using an infraclavicular approach. Patients were stratified with regard to age, gender, and body mass index.

Results:

• No significant differences in the presence of risk factors for difficult cannulation between the two groups of patients were recorded.
• Subclavian vein cannulation was achieved in 100% of patients in the ultrasound group as compared with 87.5% in the landmark one (p < .05).
• Average access time and number of attempts were significantly reduced in the ultrasound group of patients compared with the landmark group (p < .05).
• In the landmark group, artery puncture and hematoma occurred in 5.4% of patients, respectively, hemothorax in 4.4%, pneumothorax in 4.9%, brachial plexus injury in 2.9%, phrenic nerve injury in 1.5%, and cardiac tamponade in 0.5%, which were all increased compared with the ultrasound group (p < .05).
• Catheter misplacements did not differ between groups.

Conclusions: The present data suggested that ultrasound-guided cannulation of the subclavian vein in critical care patients is superior to the landmark method and should be the method of choice in these patients.

Real-time ultrasound-guided subclavian vein cannulation versus the landmark method in critical care patients: A prospective randomized study - Critical Care Medicine. 39(7):1607-1612, July 2011.

Case: Define chylothorax and describe different treatment modalities?

Answer: Chylothorax is defined as triglycerides more than 113 mg/dl (1.24 mmol/L) in pleural cavity.

A number of therapeutic interventions have been used to reduce chyle production and promote resolution of a chylothorax. Initial management typically includes restriction or temporary cessation of enteral feedings. Enteral feedings high in medium-chain triglycerides (MCT), or parenteral nutrition may be used. Total parenteral nutrition typically results in resolution in 75 to 80% of cases by that time. In resistant cases, pleurodesis, ligation of the thoracic duct, or placement of drains and pleuroperitoneal shunts may be considered.

Octreotide has become another option for management of patients with chylothorax. Although the exact mechanism by which the drug exerts its effects has not been defined, it is believed that the multiple effects of octreotide on the gastrointestinal tract and the reduction in splanchnic blood flow reduce thoracic duct flow and decrease the triglyceride content of chyle.

Q: 54 year old male with end stage liver disease may require large volume paracentesis. Patient is labeled as allergic to Albumin. What is your alternative to prevent circulatory dysfunction after large-volume paracentesis?

Answer: Use of terlipressin

The removal of 5 litres of fluid or more is considered large-volume paracentesis. The AASLD (American Association for the Study of Liver Diseases) suggests that postparacentesis albumin infusion may not be necessary for a single paracentesis of less than 5 litres; however, for large-volume paracenteses consider an albumin infusion of 8-10 g per liter of fluid removed.

Another alternative is to use terlipressin (1 mg every 4 hours for 48 hours) rather than albumin for prevention of circulatory dysfunction after large-volume paracentesis. Studies suggest that terlipressin is as effective as albumin.


References: Click to get abstract

1. The efficacy of terlipressin in comparison with albumin in the prevention of circulatory changes after the paracentesis of tense ascites --a randomized multicentric study. Hepatogastroenterology. Oct-Nov 2007;54(79):1930-3.

2. Terlipressin versus albumin in paracentesis-induced circulatory dysfunction in cirrhosis: a randomized study. J Gastroenterol Hepatol. Jan 2006;21(1 pt 2):303-7.

Q: CMV Retinitis can be treated by ganciclovir or foscarnet,   

A) orally,
B) intravenously, 
C) intravitreal injection
D) intravitreal implant
E) All of the above.

Answer: E (all of the above)

Beside regular route of administration it is interesting to note that the Vitrasert ganciclovir implant is a sustained-release intravitreal implant that is used for the treatment of cytomegalovirus (CMV) retinitis. Each implant is designed to release drug over a 5 to 8 month period.

7 "Ps" of intubation.

1. Pre-oxygenate the patient
2. Prepare the equipments
3. Put down (sedate) the patient
4. Paralyse the patient
5. Place the tube
6. Placement confirmation (via auscultation, EZcap or CXR)
7. Pen down (document) the procedure

Fentanyl Cough
Fentanyl is probably the most commonly used opioid in ICUs. Fentanyl is associated with coughing in upto 30% of patients. Usually its benign but may become explosive causing discomfort and increased intracranial and intra-ocular pressures. The various mechanisms proposed to explain fentanyl induced cough are inhibition of central sympathetic outflow leading to vagal predominance, histamine release or deformation of the tracheobronchial wall stimulating the irritant receptors.

Treatment is aerosol inhalation of Salbutamol, beclomethasone or sodium chromoglycate if needed.

Q: 52 year old male developed intracranial hemorrhage after receiving thrombolytic therapy for CVA. What is the treatment?

Answer: Transfusion of cryoprecipitate.

Prepare for administration of 6 to 8 units of cryoprecipitate containing factor VIII. It is not a bad idea to also adminster 6 to 8 units of platelets.

Q: Progesterone is also an “anticonvulsant.” True or false?

 

Answer: True

 

Catamenial epilepsy is defined as seizure exacerbation in women aligned with their menstrual cycle. It usually subsides in menopause and thought to be related to estrrogen.

 

Progesterone is the mainstay of the treatment.

Q; 52 year old female went into supraventricular tachycardia. While you call for Adenosine at bedside, clinical pharmacist inform you that patient is on chronic Aggrenox for her stroke?

Answer: Aggrenox is the combination of Aspirin and extended release Dipyridamole. Dipyridamole potentiates the action of adenosine so the lower doses (usually half) should be given. Give only half of recommended dose of Adenosine.

Q: An extremely vasculopath patient (almost impossible to obtain central line) presented to ER with organophosphate poisoning. Till Vascular team access vessel what could be an alternate route of Atropine in its symptomatic treatment?

Answer: Sublingual

Rajpal S, Ali R, Bhatnagar A, Bhandari SK, Mittal G. Clinical and bioavailability studies of sublingually administered atropine sulfate. Am J Emerg Med. Feb 2010;28(2):143-50.

Q; Succinylcholine is contraindicated (relatively) for intubation in which poisoining?

Answer: Organophosphate poisoining.


Organophosphate may potentiate effects of succinylcholine. Succinylcholine is relatively contraindicated in Organophosphate poisoining.

Q: Why blood in pleural fluid does not clot?

Answer: Hemorrhage within the pleural space generally does not clot due to 3 reasons

1. mechanical defibrination (movement of lungs)
2. activation of fibrinolytic mechanisms
3. Also, platelets disappears within hours following hemorrhage

5 Grades of SAH (Subarachnoid Hemorrhage)Subarachnoid hemorrhage (SAH) implies the presence of blood within the subarachnoid space from some pathologic process (traumatic and nontraumatic hemorrhages).




Grade I - Mild headache with or without meningeal irritation

Grade II - Severe headache but nonfocal examination, with or without mydriasis

Grade III - Mild alteration in neurologic examination, including mental status

Grade IV - Obviously depressed level of consciousness or focal deficit

Grade V - Patient either posturing or comatose

Q: Which commonly use ICU vasopressor is also used as a treatment to abort low flow priapism?

Answer: Phenyepherine

Phenylephrine is also used to abort priapism. It is diluted and injected directly into the corpora cavernosa. The mechanism of action is to cause constriction of the blood vessels entering into the penile region thus breaking the cycle that continues the priapism. Dose: Mixture of 1 ampule of phenylephrine (1 mL:1000 mcg) and dilute it with an 9 mL of normal saline. Use a 29-gauge needle, inject 0.3-0.5 mL into the corpora cavernosa, wait 10-15 minutes before repeating the dose.

Other pressor which can also be used is epinephrine. Methylene blue is also been suggested for the same pupose.

Related post: Priapism in sickle cell disease

B. anthracis and iron

B. anthracis must acquire iron in order to grow and proliferate in its host environment. The most readily available iron sources for pathogenic bacteria are the heme. In order to scavenge heme from hemoglobin and myoglobin, B. anthracis uses its secretory siderophore. These proteins separate heme from hemoglobin, allowing surface proteins of B. anthracis to transport it into the cell.



1. Hotta K, Kim CY, Fox DT, Koppisch AT. - Siderophore-mediated iron acquisition in Bacillus anthracis and related strains.- Microbiology. 2010 Jul;156(Pt 7):1918-25. Epub 2010 May 13.

2. Purohit M, Sassi-Gaha S, Rest RF., Rapid sporulation of Bacillus anthracis in a high iron, glucose-free medium. J Microbiol Methods. 2010 Sep;82(3):282-7. Epub 2010 Jul 16.

Mnemonic for Massive Hemoptysis

BATTLE CAMP

Bronchitis and bronchiectasis,
Aspergilloma,
Tumor,
Tuberculosis,
Lung abscess,
Emboli

Coagulopathy,
Autoimmune disorders, AVM and alveolar hemorrhage,
Mitral stenosis,
Pneumonia

Q: What is Rasmussen's aneurysm?


Answer: Rasmussen's aneurysm is a pulmonary artery aneurysm adjacent or within a tuberculous cavity. It may lead to rupture and fatal hemoptysis. Rasmussen's aneurysm is caused by weakening of the pulmonary artery wall from adjacent cavitary tuberculosis.


Please see: Rasmussen's aneurysm (Dr. Arni Raghavendrarao Raghuram, Department of Cardiothoracic Surgery, Meenakshi Mission Hospital and Research Center, Madurai, Tamilnadu) - pdf

Q: How Desmopressin (DDAVP) helps in uremic bleeding (Mechanism of action)?


Answer: The mechanism of action of DDAVP is believed to be - by releasing factor VIII from storage sites, potentially increasing the concentration of factor VIII and minimizing the effects of dysfunctional vWF. Larger vWF–factor-VIII multimers are reported in the plasma after infusion of DDAVP, which probably reduce bleeding time.

Tele-ICU?

Since inception of Tele-ICU (famously called eICU) about a decade ago, debate about its utility remained controversial. This month JAMA published a study to quantify the association of a tele-ICU intervention with hospital mortality, length of stay, and complications that are preventable by adherence to best practices. Study include 6290 adults admitted to 7 ICUs (3 medical, 3 surgical, and 1 mixed cardiovascular) on 2 campuses of an 834-bed academic medical center from April 26, 2005, through September 30, 2007. Electronically supported and monitored processes for best practice adherence, care plan creation, and clinician response times to alarms were evaluated.

Results

• The hospital mortality rate was 13.6% during the preintervention period compared with 11.8% during the tele-ICU intervention period.



• The tele-ICU intervention period compared with the preintervention period was associated with higher rates of best clinical practice adherence for the prevention of deep vein thrombosis (99% vs 85%) and prevention of stress ulcers (96% vs 83%), best practice adherence for cardiovascular protection (99% vs 80%), prevention of ventilator-associated pneumonia (52% vs 33%), for catheter-related bloodstream infection and shorter hospital length of stay (9.8 vs 13.3 days).



• The results for medical, surgical, and cardiovascular ICUs were similar.

Authors concluded that implementation of a tele-ICU intervention was associated with reduced adjusted odds of mortality and reduced hospital length of stay, as well as with changes in best practice adherence and lower rates of preventable complications.

Hospital Mortality, Length of Stay, and Preventable Complications Among Critically Ill Patients Before and After Tele-ICU Reengineering of Critical Care Processes - JAMA. 2011;305(21):2175-2183.Published online May 16, 2011

RIFLE criteria

Q: Uremia prolongs

A) PT
B) PTT
C) PT and PTT
D) Bleeding Time
E) PT, PTT and Bleedind Time



Answer: D) Bleeding time

Uremia is unique in the sense that it doesn't effect PT or PTT. DDAVP is the first line treatment, which acts promptly but has a short duration of action of few hours and exhibits tachyphylaxis. Conjugated estrogens has also shown promise but are slower in the onset of action (about 6 hours) but effect lasts for about 2 weeks.

Comparing different thrombolytic dosing regimens for treatment of acute pulmonary embolism

See this interesting work from China 1 on Optimal dosing of recombinant tissue-type plasminogen activator (rt-PA) in treating pulmonary thromboembolism.The aim of this study was to compare the efficacy and safety of a 50 mg/2 h rt-PA regimen with a 100 mg/2 h rt-PA regimen in patients with acute PTE in a prospective, randomized, open label trial.

118 patients with acute PTE and either hemodynamic instability or massive pulmonary artery obstruction were randomly assigned to receive a treatment regimen of either rt-PA at 50 mg/2 h (n = 65) or 100 mg/2 h (n = 53).

The efficacy was determined by observing the improvements of right ventricular dysfunctions (RVDs) on echocardiograms, lung perfusion defects on ventilation perfusion lung scans, and pulmonary artery obstructions on CT angiograms. The adverse events, including death, bleeding, and PTE recurrence, was also evaluated.


Results

Progressive improvements in RVDs, lung perfusion defects, and pulmonary artery obstructions were found to be similar in both treatment groups. This is true for patients with either hemodynamic instability or massive pulmonary artery obstruction.

Three (6%) patients in the rt-PA 100 mg/2 h group and one (2%) in the rt-PA 50 mg/2 h group died as the result of either PTE or bleeding.

Importantly, the 50 mg/2 h rt-PA regimen resulted in less bleeding tendency than the 100 mg/2 h regimen (3% vs. 10%), especially in patients with a body weight, 65 kg (14.8% vs. 41.2%, P = 0.049).

No fatal recurrent PTE was found in either group.

Authors concluded that Compared with the 100 mg/2 h regimen, the 50 mg/2 h rt-PA regimen exhibits similar efficacy and perhaps better safety in patients with acute PTE. These findings support the notion that optimizing rt-PA dosing is worthwhile when treating patients with PTE.

Comparing different thrombolytic dosing regimens for treatment of acute pulmonary embolism - Critical Care 2010, 14:323