Wednesday, December 31, 2014




Q:  What is the biggest pitfall of interpreting CRP (C-reactive protein) in suspected bacteremia?


Answer: Liver insufficiency

C-reactive protein (CRP) is a widely used marker of sepsis/bacteremia and is an independent predictor of mortality. CRP is synthesized in the liver due to inflammation. Since the CRP response in patients with liver disease is lower than in patients without liver disease, the prognostic information of initial CRP levels in patients with chronic liver disease is weak. And, the clinical management of patients with chronic liver disease and suspected infection should be based more on clinical, radiological and microbiological findings. The measurement of CRP in bacteremia is less helpful as compared with patients without liver disease.



Reference:

Janum SH, Søvsø M, Gradel KO, Schønheyder HC, Nielsen H. - C-reactive protein level as a predictor of mortality in liver disease patients with bacteremia. - Scand J Gastroenterol. 2011 Dec;46(12):1478-83.

Monday, December 29, 2014

Q:  Role of magnesium is not thoroughly known in treatment of eclampsia but what are the few mechanisms suggested?





Answer: MgSO4 has been shown to be a very effective treatment for the prevention and treatment of eclampsia. Its mechanism of action is multi-factorial,  and so has been found to be more effective than traditional anti-epileptics.

  1. Being a calcium antagonist, it causes vasodilation 
  2. MgSO4 via effect on the cerebral endothelium limits vasogenic edema 
  3. MgSO4 may also act centrally to inhibit NMDA receptors, providing anticonvulsant activity by increasing the seizure threshold.

Sunday, December 28, 2014

Q:  28 year old female presented with fever, urethral discharge, vesicular rash over body and c/o pain over right knee. What is the probable diagnosis?






Answer: Gonococcal arthritis (disseminated gonococcal infection).


Disseminated Gonococcal Infection (DGI) ia a systemic infection that follows the hematogenous dissemination of the gonococcus from infected mucosal sites to skin, tenosynovium, and joints and is characterized by fever, petechial or pustular acral lesions, asymmetric arthralgias, tenosynovitis, or septic arthritis. It affects women four times more often than men, and is most common among sexually active adolescent girls. There is also increased risk during menstruation and pregnancy.

Saturday, December 27, 2014

Q: What is the good positioning of the operator while intubating a patient?


Answer: As the operator stands behind the patient's head, the patient's head should be around at the level of the operator's lower sternum. For ideal view, the operator should keep his or her back straight all the time and should resist any attempt  to  hunch over the patient. If required, any bending should occur in the knees of the operator.

Monday, December 22, 2014

Capillary refill - a basic exam often ignored


Capillary refill is defined as the time taken for color to return to an external capillary bed after pressure is applied to cause blanching. Ideally it should be measured by holding a hand higher than heart-level, pressing the soft pad of a finger until it turns white. Its the time needed for the color to return once pressure is released. Normal capillary refill time is usually less than 2 seconds but in clinically sick patients up to 5 seconds is acceptable. A prolonged capillary refill time is a sign of shock. Capillary refill should be read with other clinical signs.

Saturday, December 20, 2014

Q: 28 year old female with 22 weeks of gestation is admitted to ICU with dehydration secondary to severe diarrhea. Patient has massive leucocytosis with abdominal pain. Patient was recently treated with antibiotics as out-patient  for her community acquired pneumonia. You want to cover her against C.diff. colitis. What would be the preferred agent?


Answer: Oral Vancomycin

Oral vancomycin is preferred over oral metronidazole for severe C.Diff. colitis anyway. Metronidazole has the potential to cause birth defects so during gestation oral vancomycin is preferred over metronidazole.





Reference:

Surawicz, Christina M; Brandt, Lawrence J; Binion, David G; Ananthakrishnan, Ashwin N; Curry, Scott R; Gilligan, Peter H; McFarland, Lynne V; Mellow, Mark et al. (26 February 2013). "Guidelines for Diagnosis, Treatment, and Prevention of Clostridium difficile Infections". The American Journal of Gastroenterology 108 (4): 478–498

Friday, December 19, 2014



Q: What are the recommendations after needlestick injury from HIV positive patient?



Answer: 
  • The site of exposure should be washed liberally with soap and water but without scrubbing.
  • Antiseptics and skin washes should not be used.
  • Free bleeding of puncture wounds should be encouraged gently but wounds should not be sucked.
Guidelines state that "feces, nasal secretions, saliva, sputum, sweat, tears, urine, and vomitus are not considered potentially infectious unless they are visibly bloody."
  • The sooner after exposure that Anti Retroviral Therapy is started the better. Guidelines recommends starting prophylaxis up to a week after exposure.
  • Recommendation is to treat for a duration of 4 weeks.
  • Recommended regimen is emtricitabine + tenofovir + raltegravir. 
  • HIV testing at 6, 12, and 24 weeks

Reference:

"Updated US Public Health Service Guidelines for the Management of Occupational Exposures to Human Immunodeficiency Virus and Recomme

Wednesday, December 17, 2014


Q: Which of the following can be used as a treatment in Torsade de Pointes except

A)Overdrive intravenous pacing
B) Cardioversion
C) Phenytoin
D) Lidocaine
E) Isoproterenol
F) Amiodarone 


Answer: F

Best treatment of Torsades De Pointes is removal of an offending cause like hypokalemia, hypomagnesemia, drugs causing prolong QTc prolongation.

IV Magnesium is the drug of choice, as bolus of  1-2 g IV over 30-60 seconds, followed by a continuous infusion. Supplemental potassium may help. Phenytoin, Lidocaine, Mexiletine and Isoproterenol has been suggested.

QT interval shortens with a faster heart rate, so overdrive pacing can be effective  at a rate of 90-110 bpm until the QT interval is normalized. Overdrive pacing may be necessary at a rate of up to 140 bpm to control the rhythm.Conversion with combination of phenytoin and overdrive pacing as been described frequently.

Amiodarone which is the mainstay of treatment in ACLS usually is ineffective. Objective of the above question is to highlight the importance of the identification of the proper rhythm. Torsade is extremely common in ICU mostly due to either electrolyte disturbance of multiple offending drugs.

Tuesday, December 16, 2014

Q: What one caveat should be known in chronically malnourished ICU patients regarding their magnesium level? 


Answer:  About 30% of magnesium is bound to albumin and is inactive. Hypoalbuminemia  may give spuriously low magnesium levels. Only free magnesium is biologically active but most methods of assessing the serum content measure total magnesium concentration. There is no formula to adjust and ionized magnesium can be obtained only by direct measurement.

Monday, December 15, 2014

Q: At what level of decreased Glomerular filtration rate (GFR), insulin resistance (IR) may occur? 


Answer:  around 50 or less

Clinical relevance: IR is common (but may go unnoticed due to its sub-clinical manifestations) in patients with mild-to-moderate CKD (Chronic Kidney Disease). Consequently, IR is an independent predictor of cardiovascular mortality in ESRD, therefore, IR may be an important therapeutic target for reduction of cardiovascular mortality in patients with CKD.

Treatment: Thiazolidinediones (TZDs) are a class of oral diabetic medications that increase insulin sensitivity in peripheral tissue. Also, proper nutritional supplementation, prevention of dyslipidemia, vitamin D deficiency and anemia  improves insulin sensitivity among the CKD population.





References:

S. Kobayashi, K. Maesato, H. Moriya, T. Ohtake, and T. Ikeda, “Insulin resistance in patients with chronic kidney disease,” American Journal of Kidney Diseases, vol. 45, no. 2, pp. 275–280, 2005.

K. Shinohara, T. Shoji, M. Emoto et al., “Insulin resistance as an independent predictor of cardiovascular mortality in patients with end-stage renal disease,” Journal of the American Society of Nephrology, vol. 13, no. 7, pp. 1894–1900, 2002.

S. M. Brunelli, R. Thadhani, T. A. Ikizler, and H. I. Feldman, “Thiazolidinedione use is associated with better survival in hemodialysis patients with non-insulin dependent diabetes,” Kidney International, vol. 75, no. 9, pp. 961–968, 2009.

Sunday, December 14, 2014


Q: 22 year old male just came out of OR to ICU after uncomplicated peri-operative course of kidney transplant. Patient is extubated and vitals are stable. Patient has good urine output. Patient has been started on protocol of anti-rejection medicines. After 30 minutes patient developed high grade fever, chills and hypotension. Clinical picture appears like septic shock. What could be other differential diagnosis? 


Answer: cytokine release syndrome

Solid organ transplants require immediate post-op infusion of Anti-Thymocyte-Globulin (ATG) infusion. ATG infusion may induce cytokine release syndrome and may causes high grade fevers, chills and rigors during administration. Cytokine infusion syndrome can be controlled/avoided with pre-medication with methylprednisolone, diphenhydramine 25–50 mg, and acetaminophen 650 mg - and by slowing the infusion rate of ATG. Cytokine release syndrome is a common immediate complication particularly after the infusion of first dose of ATG.

The pathogenesis is that the antibodies bind to the T cell receptor, activating the T cells before they are destroyed. The cytokines released by the activated T cells produce a type of systemic inflammatory response (SIRS) manifested by hypotension, fever and rigors.

Severe cases are called cytokine storms.

.

Saturday, December 13, 2014

On restraints, delirium and open visting hours in ICU

One of the trick which has been suggested and has been used successfully by nursing staff, but still under utilized is getting family online /phone/ even cam (if privacy insured) with patient.


"Parikh recalled a night during his residency rotation where instead of restraining a patient, the medical team in the ICU reoriented the patient by reminding him where he was and the time of day, offered him medication to treat his anxiety, and called his wife and put her on the telephone to provide a familiar voice. "The patient eventually calmed down without the need for restraints or other aggressive interventions, and the next morning his mental status improved," he wrote. "I hope that stories like his can become the standard, not the exception, in the ICU."


In this regards, read the following article - a hot debate in Critical Care community - regarding open ICU hours for family:

Practice Alert: family-visitation-adult-icu **

* RAVI PARIKH - Rethinking Hospital Restraints - http://www.theatlantic.com/health/archive/2014/08/rethinking-hospital-restraints/375647/

** http://www.aacn.org/WD/practice/docs/practicealerts/family-visitation-adult-icu-practicealert.pdf

Friday, December 12, 2014

Q: 62 year old male was admitted to ICU for urosepsis. Patient is recovering from sepsis. Patient c/o pain on his right great toe in the morning and resident diagnosed it with acute gout. Clinical exam shows painful and inflamed joint. Laboratory confirmed hyperurecemia. Patient  has never been treated previously for gout and is not taking any medicine on chronic basis. what would be your next step?



Answer: Rule out septic arthritis

Patient with recent sepsis should be ruled out for septic arthritis particularly in view of no previous history, Hyperurecemia may be an accidental finding. Septic arthritis may clinically looks like gout or pseudogout on exam. If un-treated septic arthritis may become life threatening. Gold standard to distinguish between septic arthritis and crystal-induced arthritis is via examination of joint fluid.


Thursday, December 11, 2014

Q: Tumor Lysis Syndrome can do all of the following except:

A) Hyperkalemia

B) Hyperphosphatemia

C) Hypercalcemia

D) Hyperuricemia


Answer: C

Tumor Lysis syndrome causes hypocalcemia instead of hypercalcemia

Cairo and Bishop defined a classification system for tumor lysis syndrome dividing it into categories

Laboratory tumor lysis syndrome: 
(abnormality in 2 or more of the following, occurring within three days before or seven days after chemotherapy).
  • uric acid > 8 mg/dL or 25% increase
  • potassium > 6 meq/L or 25% increase
  • phosphate > 4.5 mg/dL or 25% increase
  • calcium < 7 mg/dL or 25% decrease

Clinical tumor lysis syndrome: 
(laboratory tumor lysis syndrome plus one or more of the following)
  • increased serum creatinine (1.5 times upper limit of normal)
  • cardiac arrhythmia or sudden death
  • seizure


Reference:

Cairo MS, Bishop M (October 2004). "Tumour lysis syndrome: new therapeutic strategies and classification". Br. J. Haematol. 127 (1): 3–11.

Wednesday, December 10, 2014

Interesting story on foley catheter related urethral trauma
"When I was a resident, a fellow was sick of being called about a demented old man pulling his catheter and occasionally pulling it out. He was so frustrated he tucked the real catheter between his legs and taped it to the back of his leg, he then taped 7-8 dummy foleys that the patient could reach and intermittently pull on to keep himself busy!"



Source:  http://forums.studentdoctor.net/

Tuesday, December 9, 2014

Q: What is considered as an endpoint success in Barbiturate coma therapy (BCT)  from ICP (intra cranial pressure) control perspective in neurotrauma patients?


Answer: ICP < 20 mmHg for at least 48 hours, at a minimum

Patients, whose ICPs are successfully controlled by pentobarbital, had at least five times greater chance of survival. 



References:

Eisenberg HM, Frankowski RF, Contant CF, Marshall LF, Walker MD. High dose barbiturate control of elevated intracranial pressure in patients with severe head injury. J Neurosurg. 1988;69:15–23.

Etienne D, Jacques B, Arlette V, Florence L, Jean LV. Barbiturate coma for intracranial hypertension: clinical observations. J Crit Care. 2002;17:58–62.

Horsley JS. The intracranial pressure during barbital narcosis. Lancet. 1937;1:141–143.

Michael WL, Scott AD, Mary ES, Roger RB, Dan RT. The efficacy of barbiturate coma in the management of uncontrolled intracranial hypertension following neurosurgical trauma. J Neurotrauma. 1994;11:325–331.

Monday, December 8, 2014

Q: What anti-seizure medicine may cause hyperammonemic encephalopathy, despite normal liver function, normal doses and normal serum levels?


Answer: Valproic acid (VPA)

The use of valproic acid (VPA) (Depakote) frequently causes hyperammonemia. Usually it is clinically not significant but in some people, hyperammonemia may be clinically evident as encephalopathy, which may become life threatening. Valproic acid-induced hyperammonemic encephalopathy may occur in people with normal liver function, with normal doses and normal serum levels.



Reference:

Wadzinski J, Franks R, Roane D, Bayard M. - Valproate-associated hyperammonemic encephalopathy. - .J Am Board Fam Med. 2007 Sep-Oct;20(5):499-502.

Sunday, December 7, 2014

Q: What is the heterotopic heart transplant?


Answer: Mostly heart transplant is orthotopic means the patient's own heart is removed and new heart is transplanted.

In heterotopic heart transplant, surgeon may decide to leave the patient's own heart along with new heart (yes! double heart).  The chambers and blood vessels of both hearts can be connected. It may be perform when native heart has a chance to recover, there is a high likelihood of rejection, if the donor heart is sensed to be weak or the patient has underlying severe pulmonary hypertension.

Saturday, December 6, 2014

Q: Beside steroids which drug may cause hyperglycemia in post-transplant patients?


Answer: Tacrolimus

Hyperglycemia can occur in 33 to 47% of patients receiving tacrolimus. About 11 to 20% of patients develop Insulin-dependent diabetes post-transplant. In many patients it is reversible. It is found to be more common in blacks and in patients receiving high-dose steroids.

Friday, December 5, 2014

Q: 54 year old male is admitted to ICU after ischemic CVA causing dense right sided hemiplegia. Patient is scheduled to get MRI. While talking to wife, she informed you that patient had a recent work up for GI bleed as out-patient and capsule endoscopy was performed. What is your concern?


Answer: Bowel injury 

Device retention after capsule endoscopy may happen in patients with crohn's disease, neoplastic lesions, stenosis, and adhesions. The feared complication of MRI with capsule retention is migration of the capsule causing bowel perforation. It would be safe to document the passage of an endoscopic capsule before MRI by performing KUB.  Some centers recommend 30 days time period between capsule endoscopy and MRI.




Reference:

Berry PA, Srirajaskanthan R, Anderson SH. An urgent call to the magnetic resonance scanner: potential dangers of capsule endoscopy. Clin Gastroenterol Hepatol. 2010;8(5):A26

Thursday, December 4, 2014




Q: 27 year old female is in ICU after acetaminophen toxicity. Patient was promptly started on N-acetylcysteine (NAC) in ER. Patient after 10 hours of N-acetylcysteine (NAC) infusion is clinically stable. Patient acetaminophen level is markedly down. What would be your next step?

A) Continue N-acetylcysteine (NAC)

B) stop  N-acetylcysteine (NAC) to avoid fluid overload

C)  check Amylase and Lipase

D) Check ABG and LFT and if normal - discharge patient home



Answer: A

The entire NAC protocol, should be completed even if patient clinically stabalizes or the acetaminophen plasma levels decreases. There is no reason to check amylase lipase if clinical signs are normal. Also, it may help to keep eye on ABG and LFT but patient should be kept in hospital till completely clear, as extended release forms of drug may bounce back the level.

Wednesday, December 3, 2014

Q: You were surprised with black colored pleural effusion on thoracentesis. What are your differential diagnosis?


Answer:
  • infection with Aspergillus niger
  • infection with Rizopus oryzae,
  • malignant melanoma,
  • non-small cell lung cancer 
  • ruptured pancreatic pseudocyst,
  • charcoal-containing empyema


Reference:

Saraya T, Light RW, Takizawa H, Goto H. Black pleural effusion. Am J Med. Jul 2013;126(7):641.e1-6.

Tuesday, December 2, 2014

RiaSTAP



In patients with fibrinogen deficiency, now along with cryopreciptate Fibrinogen Concentrate (Human) - Trade name RiaSTEp is available. RiaSTAP is not indicated for dysfibrinogenemia, but is indicated for the treatment of acute bleeding episodes in patients with congenital fibrinogen deficiency, including afibrinogenemia and hypofibrinogenemia. It may be use in acute post-op bleeding due to hypofibrinogenemia. Dose should be individually calculated for each patient based on
  •  the target plasma fibrinogen level
  • actual measured plasma fibrinogen level and
  • body weight
formula is 
[Target level (mg/dL) - measured level (mg/dL)] /
 1.7 (mg/dL per mg/kg body weight)

When baseline fibrinogen level is not known, the recommended dose is 70 mg per kg of body weight.



Reference:

Monday, December 1, 2014

Q: Steroids are widely used in ICUs. How early it can cause psychosis?


Answer: 3 to 4 days

Steroid-induced psychosis may emerge within 3 to 4 days (to a median of 11 days) after a patient starts corticosteroid therapy. Unfortunately, even after steroids are discontinued, symptoms may persists up to 4 weeks. Meanwhile, different anti-psychotics may be used including haloperidol, olanzapine, risperidone, quetiapine, lithium, carbamazepine and others. Resistant cases may require electroconvulsive therapy. 




References:

1. Sirois F. Steroid psychosis: a review. Gen Hosp Psychiatry 2003;25:27-33.

2. Patten SB, Neutel CI. Corticosteroid-induced adverse psychiatric effects: incidence, diagnosis and management. Drug Saf 2000;22:111-22.

3.  Wada K, Yamada N, Suzuki K, et al. Recurrent cases of corticosteroid-induced mood disorder: a clinical characteristics and treatment. J Clin Psychiatry 2000;61:261-7.

4.  Brown ES, Chamberlain W, Dhanani N, et al. An open-label trial of olanzapine for corticosteroid-induced mood symptoms. J Affect Disord 2004;83:277-81.

5.  Wada K, Yamada N, Yamauchi Y, Kuroda S. Carbamazepine treatment of corticosteroid-induced mood disorder. J Affect Disord 2001;65:315-7.

6.  Siddiqui Z, Ramaswamy S, Petty F. Quetiapine therapy for corticosteroid-induced mania. Can J Psychiatry 2005;50:77-8.

7. DeSilva CC, Nurse MC, Vokey K. Steroid-induced psychosis treated with risperidone. Can J Psychiatry 2002;47:388-9.

Sunday, November 30, 2014

Q: 52 year old male is in refractory hypoxemia due to ARDS. Patient is not an ECMO candidate due to very recent neuro bleed. Pt. didn't respond to prone positioning either. In last 24 hours pulmonary artery catheter reading is showing progressive increase in pulmonary pressure. you requested iNO (inhaled nitric oxide). RT (Respiratory Therapy) service informed you that no iNO  machine is available. What could be your alternative?


Answer: Inhaled aerosolized prostacyclin 

Inhaled aerosolized prostacyclin (iAP), is an effective alternative to inhaled nitric oxide (iNO) for refractory hypoxemia and severe pulmonary hypertension. Tradiotionally, iNO is used in patients with pulmonary hypertension and acute respiratory distress syndrome (ARDS), but both iNO and iAP have been shown to reduce pulmonary vascular pressure and improve oxygenation in patients with ARDS. Moreover, it is more cost-effective also.


Reference:

Walmrath D, Schneider T, Schermuly R, Olschewski H, Grimminger F, Seeger W. - Direct comparison of inhaled nitric oxide and aerosolized prostacyclin in acute respiratory distress syndrome. -  Am J Respir Crit Care Med. 1996 Mar;153(3):991-6.

Friday, November 28, 2014

Q: What is pulsatile hepatomegaly?


Answer: In pulsatile hepatomegaly, the pulsations can be felt clinically over liver area. They can also be confirmed by external hepatic recordings. These pulsations conformed almost identically to the jugular venous pulsations in the neck. This is one of the classic sign seen in constrictive pericarditis. They should disappear after surgical treatment of constrictive pericarditis. Persistence of the hepatic pulsations after treatment signifies failure of surgical treatment.

Thursday, November 27, 2014


Q: Which side of the chest is likely to have pneumothorax in  Catamenial pneumothorax?


Answer: Right

Catamenial pneumothorax may occur in women between age 30-40 years within 48 hours of menstruation. It usually occurs on right-side and have tendency to recur.

Wednesday, November 26, 2014

Q: Which atypical anti-psychotic drug can also be used as an anti-emetic in chemotheray induced nausea and vomitting?


Answer: Olanzapine

Olanzapine can be use as an anti-emetic, particularly in chemotherapy-induced nausea and vomiting. It is highly effective if use as a cocktail with palonosetron and dexamethasone. 



Reference:

Navari RM, Einhorn LH, Loehrer PJ, Passik SD, Vinson J, McClean J, Chowhan N, Hanna NH, Johnson CS (2007). "A phase II trial of olanzapine, dexamethasone, and palonosetron for the prevention of chemotherapy-induced nausea and vomiting: A Hoosier oncology group study". Supportive Care in Cancer 15 (11): 1285–91.

Tuesday, November 25, 2014

Q: 48 year old male is going for coronary stents placement after non-ST MI. Patient has previous history of severe GERD which is responsive only to Omeprazole (proton-pumo inhibitor). Which anti-platelet would be recommended?


Answer: Prasugrel

Clopidogrel (plavix) is the most commonly used anti-platelet agent along with aspirin in patients requiring coronary stents. But, clopidogrel has shown to have decreased effect in patients using proton pump inhibitors (PPI)  particularly omeprazole or esomeprazole (pantoprazole appears to be relatively safe).

Prasugrel has minimal interaction with PPIs, hence considered to be better choice in patients who are on PPIs and require coronary stents.

Monday, November 24, 2014

Types of Myocardial Infarction



Type 1: Ischemic myocardial necrosis due to plaque rupture ( ACS) 

 Type 2: Ischemic myocardial necrosis due to supply-demand mismatch, e.g. coronary spasm, embolism, low or high blood pressures, anemia, or arrhythmias. 

 Type 3: sudden cardiac death 

 Type 4: procedure related, post PCI or stent thrombosis 

 Type 5:  post CABG

Sunday, November 23, 2014

Q: 60-year old patient presented with the compliant of shortness of breath. Patient has 60 pack-year history of smoking. Patient 

sodium is 140meq/l,
 potassium is 4meq/l, 
chloride is 94meq/l, and 
HCO3 is 36meq/l. 

 Patient abg revealed 

pCO2 is 70 and 
pH is 7.31.

 What is the acid base disturbance. 

 A) Metabolic acidosis
 B) Acute Respiratory acidosis 
 C) Chronic Respiratory acidosis 
 D) Mixed Metabolic and Respiratory acidosis 


 Answer: C

Rationale: Patient anion gap is 10 that rules out metabolic acidosis.  For every 10 Torr change in COchange in ph is 0.3 for chronic and 0.8 for acute.  Since the change in torr of CO2 in this case is 30, and ph is 7.31 that makes it chronic respiratory acidosis.  If it would have been acute that the ph should have been 7.16 (0.08x3=0.24; 7.4-.24=7.16)

Saturday, November 22, 2014

Q; 30-year old patient with history of diabetes, presented to the hospital with c/o nausea and vomiting. Patient 

sodium was 140meq/l, 
potassium was 4meq/l, 
chloride was 105meq/l, 
HCO3 was 5meq/l. 

 On ABG 

pCO2 was 16 and 
pH was 7.11. 

 What is the acid base disturbance? 

 A) Metabolic acidosis 
 B) Respiratory acidosis 
 C) Mixed metabolic and respiratory acidosis 
 D) Triple acid-base disturbance 



Answer:

 Rationale: Patient anion gap is high (30) suggestive of metabolic acidosis. Patient CO2 is low, not supporting the notion of respiratory acidosis. Expected CO2 is (pCO2=1.5(HCO3) +8 +/-2; 1.5x5+8+/-2=13.5-17.5) within normal range.

Friday, November 21, 2014

Q; Patient with history of hypertension and anxiety presented to the hospital with tachypnea. Patient 

sodium was 140meq/l, 
potassium was 3meq/l, 
chloride was 94meq/l and 
HCO3 was 34. 

 On arterial blood gas, 

PH was 7.67 and 
pCO2 was 30. 

 What is the acid base disturbance? 

 A) Respiratory alkalosis 
 B) Metabolic alkalosis 
 C) Respiratory and metabolic alkalosis 
 D) Hyperchloremic non-anion gap metabolic acidosis 



Answer:

 Rationale: Patient HCO3 is high suggestive of metabolic alkalosis. Patient expected CO2 should be (pCO2=HCO3x0.9+9; 34x0.9+9=39.6); CO2 is 30, which is lower than expected pCO2, suggestive of mixed respiratory and metabolic alkalosis.

Thursday, November 20, 2014

Patient presented to ED with complaint of vomiting and was found to be hypotensive. Patient sodium was 140meq/l, potassium was 3meq/l, chloride was 92meq/l and HCO3 was 29. On arterial blood gas the patient ph was 7.61 and pCO2 was 30. What is the underlying acid-base disturbance? 

 A) Mixed respiratory and metabolic alkalosis 
 B) Mixed respiratory alkalosis and metabolic acidosis 
 C) Respiratory alkalosis, metabolic acidosis and metabolic alkalosis 
 D) Respiratory acidosis and Respiratory alkalosis 


 Answer: C 

 Rationale: Patient PH is high suggestive of alkalosis. Patient HCO3 is high suggestive of metabolic alkalosis, the PCO2 should be high to compensate, but it is low, suggestive of concurrent respiratory alkalosis. Patient anion gap is 19 suggestive of metabolic acidosis. Hence the picture is consistent with metabolic acidosis, metabolic alkalosis and respiratory alkalosis. Patient cannot have respiratory acidosis and respiratory alkalosis together, as one cannot breath slowly and fast at the same time.

Wednesday, November 19, 2014

Case: The patient underwent serum chemistry and arterial blood gas. Patient was found to have Na of 139 meq/l, K 3 meq/l, CL 93 meq/L and HCO3 of 35. Patient pH was 7.49 and pCO2 was 41. What is the underlying acid base disturbance.

A) Mixed Respiratory and Metabolic Alkalosis
B) Respiratory Alkalosis
C) Hyperchloremic non-anion gap metabolic acidosis  
D) Metabolic Alkalosis




Answer: D. Metabolic alkalosis

Rationale: Patient has pH of 7.49 suggestive of alkalosis. pCO2 is within normal range excluding respiratory alkalosis. The pH is high and chloride is 93 meq/L showing no indication of hyperchoremic metabolic acidosis. HCO3 is high and expected pCO2is within normal range (Expected CO2=0.9 x HCO3+9; .9X35+9=40.5) suggestive of simple compensated metabolic alkalosis as seen with diuretic therapy.

Tuesday, November 18, 2014


Case: 30-year female presented with complain of mild shortness of breath. Patient sodium was 139 meq/l, Potassium was 3.5meq/l, Chloride was 107meq/l, bicarbonate was 20. Patient pH on arterial blood gas revealed pCO2of 25 and pH of 7.45. What is the underlying acid base disturbances.
   
A) Metabolic acidosis
B) Metabolic Alkalosis
C) Respiratory acidosis
D) Respiratory alkalosis


Answer: D.  -  Respiratory Alkalosis

Rationale: Patient ph is 7,45 making it alkalosis, and the bicarbonate is not high, whereas the pCO2 on arterial blood gas is low suugestive of respiratory alkalosis, as can be seen in the pregnant patient or in severe acute anxiety.

Monday, November 17, 2014



Q: 36 year old female, who is now recouping from exacerbation of Asthma in ICU and just finished her breakfast with large cup of coffee went into sustained SVT with heart rate of 240. You decided to administer Adenosine. What would be your concern?

Answer: Patient may need higher dose

Theophylline (which this patient may have use for Asthma) and caffeine antagonize adenosine's effects, so standard dose of 6 mg IV bolus may not work and an increased dose of adenosine may be required. On the contrary, Dipyridamole potentiates the action of adenosine, requiring the use of half of the standard dose.

Sunday, November 16, 2014

QHow just eye balling pulse oximetry on monitor can help in diagnosis of patient having suspicion of cardiac tamponade?


Answer: Patients with suspicion of cardiac tamponade, usually show increased respiratory variability in pulse-oximetry waveform.


Reference:


Stone MK, Bauch TD, Rubal BJ. Respiratory changes in the pulse-oximetry waveform associated with pericardial tamponade. Clin Cardiol. Sep 2006;29(9):411-4

Saturday, November 15, 2014


Q: How much water need to be mixed to prepare one vial of Dantrium?

Answer: 60 cc

Each vial of Dantrium Intravenous should be reconstituted by adding 60 mL of sterile water and the vial shaken until the solution is clear. 5% Dextrose or 0.9% Sodium Chloride are not compatible with Dantrium Intravenous.

Dantrium is used for the prophylaxis and treatment of Malignant Hyperthermia (MH). The recommended prophylactic dose of Dantrium Intravenous is 2.5 mg/kg, starting approximately 60-75 minutes before anticipated anesthesia. It requires infusion over approximately 1 hour.

In post crisis intravenous Dantrium is used to attenuate malignant hyperthermia. The i.v. dose of Dantrium in the postoperative period starts with 1 mg/kg or more as the clinical situation dictates.

Friday, November 14, 2014

Q: Which pericarditis does not usually presents with classic ST elevations on EKG


Answer: Uremic pericarditis

In Uremic Pericarditis, classic finding of diffuse ST elevations are rare; rather more commonly, non- specific repolarization changes are present. This is due to the relative lack of  epicardial electrical injury. Also, pericardial fluid  is enriched with  oppositely charged uremic molecules  which neutralizes the electrical gradient.

Thursday, November 13, 2014

Q: What is the difference between hypertensive urgency and hypertensive emergency?


Answer: 

Hypertensive urgency: is defined as severely elevated blood pressure (ie, systolic >180-220 mm Hg or diastolic >110- 120 mm Hg) with no evidence of target organ damage.

Hypertensive emergency: is defined as a recent significant increase over baseline blood pressure that is associated with target organ damage causing CVA, acute MI or angina, Renal insufficiency, Aortic dissection, Pulmonary edema, Eclampsia etc.

Clinical significance: Hypertensive emergencies require immediate therapy. In contrast, no evidence suggests a benefit from rapidly reducing blood pressure in patients with hypertensive urgency. In fact, such aggressive therapy may harm the patient, causing organ hypoperfusion.

Wednesday, November 12, 2014

Q: Why inhaled intrinsic Nitric oxide should always be weaned instead of abrupt discontinuation


Answer:  Abrupt discontinuation of inhaled NO may cause severe rebound pulmonary hypertension, an increase in intrapulmonary right-to-left shunting, and a decreased PaO2.

Exact mechanism is not known but It has been suggested that downregulation of endogenous NO synthesis and/or elevated endothelin-1 levels by inhaled NO is probably responsible for this rebound.

Slow stepwise weaning of the inhaled NO concentration is recommended.


References;

1. Rossaint R, Falke KJ, Lopez F, et al. Inhaled nitric oxide for the adult respiratory distress syndrome. N Engl J Med. 1993; 328: 399–405.

2. Black SM, Heidersbach RS, McMullan DM, et al. Inhaled nitric oxide inhibits NOS activity in lambs: potential mechanism for rebound pulmonary hypertension. Am J Physiol Heart Circ Physiol. 1999; 277: H1849–H1856.

3. McMullan DM, Bekker JM, Johengen MJ, et al. Inhaled nitric oxide-induced rebound pulmonary hypertension: role for endothelin-1. Am J Physiol Heart Circ Physiol. 2001; 280: H777–H785.

Tuesday, November 11, 2014



Q: Can sildenafil be given as IV in the treatment of pulmonary hypertension?



Answer:  Yes

IV sildenafil as a bolus in dose from 2.5 mg to 10 mg (tid) has been shown as a potent dilator in pulmonary hypertension. At least one study in children has shown it to be as effective as iNO.




Reference:


Ingram Schulze-Neick, MD; Paulina Hartenstein, BSc; Jia Li, MD; Brigitte Stiller, MD; Nicole Nagdyman, MD; Michael Hübler, MD; Ghazwan Butrous, MD; Andy Petros, MD; Peter Lange, MD; Andrew N. Redington, MD - Intravenous Sildenafil Is a Potent Pulmonary Vasodilator in Children With Congenital Heart Disease -  Circulation. 2003; 108: II-167-II-173

Monday, November 10, 2014


Q: Which one disease process need to be ruled out in severe pruritus associated with kidney failure, also known as Uremic pruritus?


Answer:  Hyperparathyroidism

If despite symptomatic treatment and increasing the dose/frequency of dialysis - uremic pruritus is not resolving, other disease processes particularly hyperparathyroidism need to be ruled out. Data is almost 45 years old but still is clinically relevant. 




References:

1. Massry S, Popovzer MM, Coburn JM, Mokoff DL, Maxwell MH, Kleeman CR. Interactable pruritus as a manifestation of secondary hyperparathyroidism in uremia. N Engl J Med1968; 279: 697–700

2. Hampers CL, Katz AI, Wilson RE, Merrill JP. Disappearence of uremic itching after subtotal parathyreoidectomy. N Engl J Med1968; 279: 695–697

3. Stahle‐Bäckdahl M, Hägermark O, Lins LE, Törring O, Hilliges M, Johansson O. Experimental and immunohistochemical studies on the possible role of parathyroid hormone in uremic pruritus. J Intern Med1989; 225: 411–415

Sunday, November 9, 2014

Q: 56 year old male with ESRD is admitted to ICU with VRE pneumonia and sepsis.  Due to hemodynamic compromise, initially patient was put on CRRT. Patient responded well to Linezolid and is now switched to regular hemodialysis (HD). What care should be taken to maintain efficacy of Linezolid?


Answer:  Administer linezolid after HD session.

HD removes 30–40% of a dose of Linezolid so it should be given after HD session on the day of dialysis.  In CRRT no adjustment is needed but every 8 hours administration instead of every 12 hours of total daily dose is advisable.

Saturday, November 8, 2014

Q: Can SLEDD (sustained low-efficiency daily dialysis) be done via AV fistula?


Answer:  Yes.

One advantage of SLEDD over CRRT (continuous renal replacement therapy) is that it can be done over AV fistula - and placement of dialysis catheter is not required.