Monday March 9, 2009


Q: What is Modified Rankin Scale?


Answer: The modified Rankin Scale, also written as mRS is a commonly used scale for measuring the degree of disability or dependence in the daily activities of people who have suffered a stroke. It was originally introduced in 1957 by Rankin. It was modified in 1988.

SCORE

0 = No symptoms at all

1 = No significant disability despite symptoms; able to carry out all usual duties and activities

2 = Slight disability; unable to carry out all previous activities, but able to look after own affairs without assistance

3 = Moderate disability; requiring some help, but able to walk without assistance

4 = Moderately severe disability; unable to walk without assistance and unable to attend to own bodily needs without assistance

5 = Severe disability; bedridden, incontinent and requiring constant nursing care and attention

6 = Dead


References

Rankin J. “Cerebral vascular accidents in patients over the age of 60.” Scott Med J 1957;2:200-15.
Bonita R, Beaglehole R. “Modification of Rankin Scale: Recovery of motor function after stroke.” Stroke 1988 Dec;19(12):1497-1500

Sunday March 8, 2009
DVTs in ICUs

Q: Despite universal thromboprophylaxis, medical-surgical critically ill patients remain at risk for lower extremity deep venous thrombosis. Name few independent risk factors for intensive care unit-acquired deep venous thrombosis?


Answer:

• personal or family history of venous thromboembolism
• end-stage renal failure
• platelet transfusion
• vasopressor use

Reference: Click to get abstract

Deep venous thrombosis in medical-surgical critically ill patients: Prevalence, incidence, and risk factors - Critical Care Medicine:Volume 33(7)July 2005pp 1565-1571

Saturday March 7, 2009


Q: Which pressor is preferable to counter-act vasodilatation (hypotension) induced by milrinone during or immediate post-op Coronary bypass surgery? (choose one)

A) Norepinephrine
B) Dopamine
C) Vasopressin
D) Phenylepherine


Answer: Vasopressin

Phosphodiesterase inhibitor is used during coronary bypass surgery in management of decompensated heart failure because it increases contractility and decreases afterload of right ventricle. It also improves hemodynamics and increases blood flow of the grafted internal mammary arteries and middle cerebral arteries during coronary artery bypass surgery. However, it induces vasodilation and necessitates the use of vasoconstrictors.

In the patients undergoing CABG surgery, both norepinephrine and low dose vasopressin were effective in restoring milrinone-induced decrease of SVR. However, only low-dose vasopressin decreased the PVR/SVR ratio that was increased by milrinone. Considering the importance of maintaining systemic perfusion pressure as well as reducing right heart afterload, milrinone–vasopressin may provide better hemodynamics than milrinone–norephinephrine during the management of right heart failure.

SVR = systemic vascular resistance
PVR = pulmonary vascular resistance


Reference: Click to get abstract

Comparative hemodynamic effects of vasopressin and norepinephrine after milrinone-induced hypotension in off-pump coronary artery bypass surgical patients - European Journal of Cardio-Thoracic Surgery, Volume 29, Issue 6, Pages 952-956 (June 2006)

Friday March 6, 2009 (pediatric pearl)

Is the survival of pediatric oncology patients with severe sepsis any different from those without oncologic malignancies?

In a retrospective study patients (446 ICU admissions of 359 eligible patients) with cancer admitted to the ICU with severe sepsis overall ICU mortality was 17%. 30% in post-bone marrow transplant (BMT) admissions and 12% in non-BMT admissions. In the 106 admissions progressing to septic shock and requiring both mechanical ventilation and inotropic support, ICU mortality was 64% with BMT patients carrying a significantly lower survival rate than non-BMT patients (26% vs. 44%).

6-month survival was 69% among non-BMT patients vs. 39% for BMT patients. When the 38 patients who survived to ICU discharge after requiring both mechanical ventilation and inotropic/vasopressor support are considered 71% were alive at 6 months after ICU discharge (81% non-BMT vs. 19% for BMT patients.

Factors significantly associated with ICU mortality in admissions requiring both mechanical ventilation and inotropic support identified four variables:

• BMT,
• fungal sepsis,
• use of multiple inotropes, and
• Pediatric Risk of Mortality III score
  

The results regarding ICU survival are useful in that the overall mortality (83%) in these particular study subjects are in line with current estimates. This implies that they carry the same prognosis as any other pediatric patient with severe sepsis. However, when comparing those patients who underwent BMT versus those who did not, the BMT patients carried a significantly lower survival rate (70% vs. 88%). The number of patients alive at 6 months and the encouraging ICU survival rate further justifies the use of aggressive ICU interventions in this population. This is useful in that it may help provide patients/parents with realistic goals and expectations of outcome.

Reference: Click to get abstract

Outcome of severe sepsis in pediatric oncology patients - Pediatr Crit Care Med. 2005 Sep;6(5):531-536

Thursday March 5, 2009
Influence of Nebulized Unfractionated Heparin and N-Acetylcysteine in Acute Lung Injury after Smoke Inhalation Injury

Andrew Miller did an interesting study to see effect of addition of nebulized unfractionated heparin, and NAC in lung injury after smoke inhalation. They studied 30 mechanically ventilated adult subjects who were admitted within 48 hours of their bronchoscopy confirmed smoke inhalation injury over a 5-year period.

The experimental group was treated with nebulized heparin sulfate, N-acetylcystine, and albuterol sulfate. Controls received ventilation support and albuterol sulfate. The authors calculated acute physiology and chronic health evaluation (APACHE)-III scores on admission in addition to daily LIS for 7 days.

The experimental group showed significant improvement in (Lung Injury Scores) LISs, respiratory resistance and compliance measurements, and hypoxia scores as compared with controls throughout the duration of the study. There was a statistically significant survival benefit in the experimental group that was most pronounced in patients with APACHE-III scores more > 35. Survival for the control vs. experimental group was 0.5714 ± 0.1497 vs. 0.9375 ± 0.0605, respectively, (risk ratio -0.0055; 95% confidence interval -0.0314-0.0204; hazard ratio 1.003; number needed to treat 2.7)

Conclusion: The use of aerosolized unfractionated heparin and N-acetylcystine attenuates lung injury and the progression of acute respiratory distress syndrome in ventilated adult patients with acute lung injury following smoke inhalation.


Reference:

Miller A, Rivero A, Zaid S, Smith D, Elamin E. Influence of Nebulized Unfractionated Heparin and N-Acetylcysteine in Acute Lung Injury after Smoke Inhalation Injury. Journal of Burn Care & Research:Volume 2009; 30(2): 249-256

Wednesday March 4, 2009
Hypothermia after cardiac arrest: Have we gone overboard

Frieberg and Neilsen looked at the two published trial for this purpose.

Objective: The aim of the study was to evaluate the actual use of hypothermia in clinical practice, safety aspects, resource utilization, and outcome in large cohorts of patients.

Method: They looked at the two published studies from two separate registries, including 2205 cardiac arrest patients in 39 different sites, of whom 869 (39%) were treated with induced hypothermia. Another registry, The Hypothermia Registry, includes 1108 patients from 37 sites in six European countries and one center in the United States; a large majority, or 952 patients (86%), were treated with hypothermia.

Conclusions: Hypothermia is feasible to implement, that it seems reasonably safe, and that the outcome compares well with previous reports. They also conclude that the treatment with hypothermia after cardiac arrest is more widely applied than what is strictly evidence based.


Editors' comment: Institutions need to develop, implement and follow guidelines for post-cardiac arrest therapeutic hypothermia to avoid indiscriminate use and save costs.


Reference:

Frieberg H, Nielsen N. Hypothermia after Cardiac Arrest: Lessons Learned from National Registries. Journal of Neurotrauma. ahead of print. doi:10.1089/neu.2008.0637.

Tuesday March 3, 2009
Minimally invasive craniopuncture therapy for basal ganglia bleed

Study by Wen-Zhi Wang from china help to shed some light on this issue. They evaluated the effects of minimally invasive craniopuncture therapy compared with conservative treatment in treating intracerebral hemorrhage (25–40 ml) in the basal ganglion.

Method: A multicenter, randomized control clinical trial comprised 465 cases of hemorrhage in the basal ganglion from 42 hospitals in China. Three hundred and seventy-seven patients with hemorrhage were randomly assigned to receive

• minimally invasive craniopuncture therapy (n=195) or
• conservative control treatment (n=182)

The main indices of evaluation were

• the degree of neurological impairment at the 14th day after treatment,
• activities of daily living at the end of the 3rd month and
• the case fatality within 3 months

Results:

• Improvement of neurological function in the minimally invasive craniopuncture group was significantly better than that in the control group at the 14th day (χ2=7·93, P=0·02).
• At the end of the 3rd month, there was a significant difference between the two groups in activities of daily living score (χ2=23·13, P<0·001).>The proportion of dependent survival patients (modified Rankin scale >2) in the craniopuncture group (40·9%) was significantly lower than that in the conservative group (63·0%) at the end of the 3rd month (χ2=16·95, P<0·01).>There was no significant difference in the cumulative fatality rates within three months between the two groups [6·7% (13/195) in the craniopuncture group and 8·8% (16/182) in the conservative group].

Conclusions: Minimally invasive craniopuncture technique can improve the independent survival of patients with small basal ganglion hemorrhage. It is a safe and practical technique in treating cerebral hemorrhage.



Reference: click to get abstract

Zhi Wnag W, Jiang B, Mei Liu H, et al. Minimally invasive craniopuncture therapy vs. conservative treatment for spontaneous intracerebral hemorrhage: results from a randomized clinical trial in China International Journal of Stroke 2009; 4(1): 11-16

Monday March 2, 2009


Q: Why oxygen should be administered to every patient with suspected PE, even when the arterial PO2 is perfectly normal?


Answer; Oxygen should be administered to every patient with suspected PE, even when the arterial PO2 is perfectly normal, because increased alveolar oxygen may help to promote pulmonary vascular dilatation.

Sunday March 1, 2009


Q: In which clinical condition, usually a lower maintenance dose of warfarin is required?


Answer; In thyrotoxic atrial fibrillation

The recommended loading dose of warfarin in thyrotoxic atrial fibrillation is similar to euthyroid patients, but a lower maintenance dose is required because of accelerated clearance of vitamin K-dependent clotting factors.



Reference:

Shenfield GM. Influence of thyroid dysfunction on drug pharmacokinetics. Clin Pharmacokinet. 1981;6:275-297