Tuesday, October 30, 2012

Blood glucose control for ICU patients

NEJM Article (Sept 20, 2012)

Hypoglycemia and Risk of Death in Critically Ill Patients

In critically ill patients, intensive glucose control leads to moderate and severe hypoglycemia, both of which are associated with an increased risk of death. 

Understanding Low Sugar from NICE-SUGAR (Commentary):

Given the current stage of evolution in inpatient insulin therapy, what are the best glucose targets for patients admitted to the ICU? In many hospitals, maintaining blood glucose at levels similar to those in the conventional-control group of the NICE-SUGAR population is safe and similar to other recommendations (140 to 180 mg per deciliter).

Key Points:

  • ICU patients were randomized to intensive (target BS 81-108 mg/dL) vs conventional (target BS 180 mg/dL) blood glucose control.
  • Mean BS in intensive control gp = 115 mg/dL vs conventional gp = 144 mg/dL
  • Intensive control gp had 2.6% absolute increased risk of death in 90d vs conventional gp (NNH = 38). 
  • Moderate hypoglycemia (blood glucose level, 41–70 mg/dL) was significantly more common in the intensive-control group than in the conventional control group (74% vs. 16%). 
  • Almost all (93%) of the 223 patients who experienced severe hypoglycemia (blood glucose level <40 mg/dL) were in the intensive-control group. 
  • Hypoglycemia was associated with longer ICU stay, longer hospital stay, and mortality. 
  • Patients with worse outcomes included those who experienced more than one episode of hypoglycemia and those with severe hypoglycemia despite not having received insulin (reflecting that hypoglycemia can result from severe illness). 
  • The adjusted hazard ratios for death were 1.41 in patients with moderate hypoglycemia and 2.10 in patients with severe hypoglycemia.

Monday, October 22, 2012

Clearing up the confusion: minimizing postoperative delirium



Lionel Lim, MD, MPH, FACP, FACPM

Postoperative delirium is an under-diagnosed yet common geriatric syndrome that manifests as an acute confusional state, typically within 48 to 72 hours after surgery.  Occurrence of postoperative delirium is variable (15-25% in elective surgery) and its incidence is highest in hip and coronary artery bypass surgeries (>50%).1  Delirium in elderly patients is associated with increased mortality, hospital length of stay, institutionalization, and dementia.2, 3  Furthermore, functional and cognitive impairment from delirium may persist for months after discharge from hospital.1  Risk factors for delirium are older age, neurocognitive impairment, multiple comorbidities, functional and sensory impairments, male gender and alcoholism.1  Patients should be screened for risk factors or cognitive impairment at baseline so that appropriate delirium-preventing interventions can be implemented. 

It is also important to educate the patient and family regarding the etiology, treatment and prognosis of delirium.  Informing family that delirium is not permanent and may take weeks to months to eventually resolve may help to reduce anxiety or frustration.  Having the support and continued presence of family members or caregivers can also help patients during their recovery by providing frequent orientation, reassurance, and avoiding the need to institute unfamiliar “sitters” or physical restraint use during episodes of confusion.  Providers should pay close attention for delirium occurrence in previously affected or high-risk patients by using a validated screening tool like the Confusion Assessment Method (CAM).4  Appropriate steps should be taken to avoid the precipitants mentioned above and to correct and treat any underlying infective or metabolic derangements.  

Patients at high risk of post-operative delirium should be followed closely by an interdisciplinary team that is knowledgeable in the prevention, detection and management of delirium.  This team should include a geriatrician or internist working in a setting with established protocols in place to reduce the risk of postoperative delirium.5  These protocols would include adequate postoperative pain management, early mobilization, close monitoring of fluid status to avoid dehydration, adequate cognitive stimulation to maintain orientation, maintenance of diurnal rhythm through nonpharmacologic sleep protocols, bowel regimens to avoid constipation, minimizing the use of bladder or vascular catheters, and avoiding deliriogenic medications (benzodiazepines or sedatives and highly anticholinergic medications, e.g. diphenhydramine).  Implementation of the Hospital Elder Life Program (HELP) which targets some of the above risk factors and includes a nonpharmacologic sleep protocol in hospitalized older adults has been shown to reduce the risk of delirium by over a third.6  Although haloperidol for postoperative delirium prophylaxis may be a promising agent for use in high risk patients, larger trials are needed before their routine use can be justified in higher-risk patients.7-9

References

1.            Marcantonio ER. In the clinic. Delirium. Ann Intern Med. Jun 7 2011;154(11):ITC6-1 to 6-16.
2.            Inouye SK. Delirium in older persons. N Engl J Med. Mar 16 2006;354(11):1157-1165.
3.            Witlox J, Eurelings LS, de Jonghe JF, Kalisvaart KJ, Eikelenboom P, van Gool WA. Delirium in elderly patients and the risk of postdischarge mortality, institutionalization, and dementia: a meta-analysis. Jama. Jul 28 2010;304(4):443-451.
4.            Inouye SK, van Dyck CH, Alessi CA, Balkin S, Siegal AP, Horwitz RI. Clarifying confusion: the confusion assessment method. A new method for detection of delirium. Ann Intern Med. Dec 15 1990;113(12):941-948.
5.            Marcantonio ER, Flacker JM, Wright RJ, Resnick NM. Reducing delirium after hip fracture: a randomized trial. J Am Geriatr Soc. May 2001;49(5):516-522.
6.            Inouye SK, Bogardus ST, Jr., Charpentier PA, et al. A multicomponent intervention to prevent delirium in hospitalized older patients. N Engl J Med. Mar 4 1999;340(9):669-676.
7.            Girard TD, Pandharipande PP, Carson SS, et al. Feasibility, efficacy, and safety of antipsychotics for intensive care unit delirium: the MIND randomized, placebo-controlled trial. Crit Care Med. Feb 2010;38(2):428-437.
8.            Kalisvaart KJ, de Jonghe JF, Bogaards MJ, et al. Haloperidol prophylaxis for elderly hip-surgery patients at risk for delirium: a randomized placebo-controlled study. J Am Geriatr Soc. Oct 2005;53(10):1658-1666.
9.            Wang W, Li HL, Wang DX, et al. Haloperidol prophylaxis decreases delirium incidence in elderly patients after noncardiac surgery: a randomized controlled trial*. Crit Care Med. Mar 2012;40(3):731-739.

How to Decrease Your Risk of Dementia with Cognitive Activities



Daviglus ML, Plassman BL, Pirzada A, et al. Risk Factors and Preventive Interventions for Alzheimer Disease: State of the Science. Arch Neurol. 2011;68(9):1185-1190.
·         Four cohort studies on the association between cognitive engagement and development of AD:
o   In all 4 studies, participants had normal cognition at baseline, and self-reported frequency of involvement in specific activities was assessed
o   All 4 studies showed a somewhat decreased risk of AD associated with greater involvement in cognitive activities.
Study 1
Verghese J, Lipton RB, Katz MJ,  et al.  Leisure activities and the risk of dementia in the elderly.  N Engl J Med. 2003;348(25):2508-2516
PubMed  |  Link to Article
1.       reading,
2.       playing board games,
3.       playing musical instruments, and
4.       dancing.
·         Increased participation in cognitive activities at base line was associated with reduced rates of decline in memory.


Study 2
Akbaraly TN, Portet F, Fustinoni S,  et al.  Leisure activities and the risk of dementia in the elderly: results from the Three-City study.  Neurology. 2009;73(11):854-861
PubMed  |  Link to Article
·         Cognitive activities in which seeking or processing information plays a central role.
1.       Doing crosswords,
2.       playing cards,
3.       attending organizations,
4.       going to cinema/theater, and
5.       practicing an artistic activity


Study 3
Wilson RS, Mendes De Leon CF, Barnes LL,  et al.  Participation in cognitively stimulating activities and risk of incident Alzheimer disease.  JAMA. 2002;287(6):742-748
PubMed  |  Link to Article
·         7 common activities that involve information processing as a central component:
1.       viewing television;
2.       listening to radio;
3.       reading newspapers;
4.       reading magazines;
5.       reading books;
6.       playing games such as cards, checkers, crosswords, or other puzzles; and
7.       going to museums.


Study 4
Wilson RS, Scherr PA, Schneider JA, Tang Y, Bennett DA. Relation of cognitive activity to risk of .developing Alzheimer disease.  Neurology. 2007;69(20):1911-1920
PubMed  |  Link to Article
·         Level of cognitively stimulating activity in old age is related to risk of developing dementia.
·         More frequent participation in cognitive activity was associated with reduced incidence of AD.
·         Frequent cognitive activity was also associated with reduced incidence of mild cognitive impairment and less rapid decline in cognitive function.
·         Common activities in which seeking or processing information played a central role:
1.       reading a newspaper,
2.       playing games like chess or checkers,
3.       visiting a library, or
4.       attending a play

Friday, October 12, 2012

More on atrial fibrillation & anticoagulation

Excellent review article on the newer anticoagulants for stroke and systemic embolism reduction in AF:

ACP Journal Club 18 Sept 2012

 

The CHA2DS2-VASc score identifies those patients with atrial fibrillation and a CHADS2 score of 1 who are unlikely to benefit from oral anticoagulant therapy 

European Heart Journal Oct 2012

 

Various risk stratification schemes predict ischemic stroke and bleeding in atrial fibrillation


Friberg L, Rosenqvist M, Lip GY. Evaluation of risk stratification schemes for ischaemic stroke and bleeding in 182 678 patients with atrial fibrillation: the Swedish Atrial Fibrillation cohort study. Eur Heart J. 2012;33:1500-10.
The CHA2DS2-VASc score had 100% sensitivity and 6% specificity for predicting stroke in patients with atrial fibrillation; CHADS2 and Framingham scores had slightly lower sensitivities but higher specificities.

Commentary: In their analysis of 7 risk stratification schemes, Friberg and colleagues found that CHADS2, CHA2DS2-VASc, and Framingham were the most accurate for predicting ischemic stroke, with c-statistics of 0.66 to 0.67. They also concluded that the 2 risk stratification schemes for bleeding had “similar predictive value,” but HEMORR2HAGES had a higher c-statistic than the HAS-BLED scheme in 7 of 8 subgroups and the same value in 1 subgroup. A new risk stratification scheme, ATRIA (Anticoagulation and Risk Factors in Atrial Fibrillation), was not evaluated (1).


Warfarin-associated major hemorrhage predicted by 7 risk stratification schemes in patients with atrial fibrillation
ACP Journal Club 15 Nov 2011
The ATRIA risk score has the potential to be a major clinical tool but needs further validation in other populations and comparisons with similar risk scores, such as HAS-BLED (2).
 ATRIA risk score had a similar c-statistic (0.69) to HEMORR2HAGES (0.67).

 

Patients at High Risk for Falls: A Reason Not to Anticoagulate?
(from Journal Watch)

Donzé J et al. Risk of falls and major bleeds in patients on oral anticoagulation therapy. Am J Med 2012 Aug; 125:773
Among patients taking anticoagulants, high risk for falls was not associated with elevated risk for major bleeding.
Despite the proven benefits of oral anticoagulants in preventing and treating certain cardiovascular and cerebrovascular diseases, they are underprescribed. Fear of falls is the most commonly cited reason. Prior studies suggest that high fall risk should not be a contraindication to oral anticoagulant use, but these studies were limited by retrospective design or exclusion of patients at high risk for falls.
Researchers evaluated whether fall risk is associated with risk for major bleeding in a prospective study of 515 patients (median age, 71) who were treated with vitamin K antagonists at a hospital in Switzerland. Patients were considered to be at high risk for falls if they answered yes to either of two validated questions: (1) Did you fall during the last year? (2) Did you notice any problem with gait, balance, or mobility? Sixty percent of patients were categorized as high risk and all others as low risk. Times to first major bleeding event (including fatal or intracranial) within the 12-month follow-up did not differ significantly between the groups. Polypharmacy was associated independently with risk for major bleeds, with a 12% increase in risk for each additional drug taken.
Comment: This study adds to evidence that patients should not be denied oral anticoagulation solely on the basis of high risk for falls. For patients with valid indications for anticoagulation, benefit generally outweighs risk. For example, an analytic model suggests that older patients (age, ≥65) who have a 5% annual risk for stroke (i.e., CHADS2 score of 2–3) and are taking anticoagulants would need to fall approximately 295 times yearly for risks of fall-related subdural hemorrhages to outweigh benefits of stroke prevention (Arch Intern Med 1999; 159:677). In addition, providers should be aware of risks conferred by polypharmacy in patients taking anticoagulants and should discontinue unnecessary medications, monitor patients more closely, or both.