Primecuts – This Week In The Journals

December 20, 2011


By Jason Feliberti, MD

Faculty Peer Reviewed

“Tis the season to be Jolly,” and if you’re like me “Tis the season to hope for new [electronic] toys.” The Holidays are around the corner, and if there is any evidence behind the massive shopping that was done during the Black Friday weekend, new electronics are the hot items. However, in the medical profession where so much movement is towards the implementation of technology to improve care-coordination and patient outcomes; some speculate that these devices may be removing us from our goal of improving patient care.

Like many other medical institutions, NYU has adopted wireless technology to improve communication between physicians, and provide instant access to relevant medical reference material and drug information. However, as noted in a recent NY Times article, the focus on these electronic devices may be distracting us from patient care [Richtel, M. 2011]. The distractions may range from too much focus on the “iPatient” over the real one, to wasting work hours on Facebook, Ebay or Twitter. The article references a peer-reviewed survey of 439 medical technicians published this year in the journal Perfusion, where it was found that 55 percent of technicians who monitor cardio-pulmonary bypass machines acknowledged using wireless devices during heart surgery. Half said they had texted while in surgery. Approximately 40 percent reported they believed talking on the phone during surgery to be “always an unsafe practice,” and half said the same about texting. The study’s authors concluded, “Such distraction have the potential to be disastrous.” [Smith, T. 2011] An example of such a disaster was provided in a medical malpractice claim in Denver, where a neurosurgeon was distracted during an operation by making personal phone calls on his wireless headset, resulting in a patient being partially paralyzed after the surgery. The case was settled before a lawsuit was filed. There is great benefit in the utilization of technology for patient care, but Dr. Peter J. Papadakos, an anesthesiologist and director of critical care at the University of Rochester Medical Center, warns of his gut feeling that “lives are in danger… we’re not educating people about the problem, and it’s getting worse.” [Papadakos, PJ. 2011] So, we know electronic distractions during surgery are dangerous; but what about liberal red-cell transfusion strategies in the post-surgical patient?

The use of red-cell transfusion is an accepted practice, but the triggers to initiate transfusion, particularly the hemoglobin threshold, remains a controversial topic. Moreover, there is a significant cost in procuring and maintaining adequate blood supplies [Carless, PA; 2010]. In clinical practice we reference the Transfusion Requirements in Critical Care (TRICC) trial to help guide our management. The TRICC trial compared a threshold of 10 g per deciliter (dL) with a threshold of 7 g /dL in patients in the intensive care unit (ICU). Overall, 30-day mortality was similar in the two groups, but in the predefined subgroups of patients under the age of 55 years and those who were less critically ill, rates of death were significantly lower in the restrictive-strategy group. Complications occurring in the ICU were also similar overall, with the notable exception of a significantly higher number of cardiac events in the restrictive-strategy group. Thus, the overall results suggested similar outcomes with a lower versus higher transfusion threshold; but this might not be applicable to patients with active cardiac disease. [Herbert, PC. et. al. 1999; Barr, PJ. 2011].

The FOCUS trial was designed to answer this question of a liberal versus restrictive red-cell transfusion strategy in patients with a history of or risk for ischemic heart disease and were undergoing surgical repair of a fractured hip [Carson, JL. 2011]. In this study, 2016 patients over the age of 50 years (mean, 81.6) were randomly assigned to either a liberal strategy group or a restrictive strategy group once their hemoglobin level fell below 10 g /dL. In the liberal strategy group single unit red-cell transfusions were given to maintain a hemoglobin level above 10 g /dL. In the restrictive strategy group the target hemoglobin level was 8 g /dL. In both groups, transfusion of red-cells were allowed for symptomatic anemia. The primary outcome was death or an inability to walk 10 ft without human assistance (a functional outcome likely to be affected by anemia) at 60 days after randomization, which was ascertained via telephone calls by blinded assessors. The study was well powered to assess their primary outcome, with results showing no difference in either the restrictive-strategy group or the liberal strategy group (35% of patients in each group were unable to walk unassisted, and 142 patients died, 76 from the liberal strategy group). Moreover, the restrictive strategy group received only half the number of transfusions administered in the liberal strategy group. There were no significant differences between groups among predefined secondary and tertiary outcomes, including in-hospital myocardial events, other coexisting illnesses, and final discharge destination, but the study was not adequately powered to assess these outcomes. Of note, the absolute difference in hemoglobin levels between the two groups was 1.3 g/dL (P<0.001), and the rate of cardiovascular events was approximately 6% in both groups. The FOCUS trial provides new evidence that a restrictive transfusion threshold in the absence of symptomatic anemia may be a reasonable strategy even in patients at risk for cardiovascular events. We will now move on to another secondary prevention study published this week in The New England Journal of Medicine.

Does raising HDL matter in the secondary prevention of cardiovascular events and is Niacin useful in achieving this goal? The AIM-HIGH Investigators attempted to answer the question if adding extended-release niacin to simvastatin therapy is superior to simvastatin therapy alone in reducing cardiovascular risk in patients with established cardiovascular disease. In this double-blind randomized control trial 3414 patients were randomly assigned to receive extended-release niacin, 1500 to 2000 mg per day, or matching placebo (which contained 50 mg of immediate-release niacin). All patients received simvastatin, 40 to 80 mg per day, plus ezetimibe, 10 mg per day, if needed, to maintain an LDL cholesterol level of 40 to 80 mg per deciliter (dL). The primary end point was the first event of the composite of death from coronary heart disease, nonfatal myocardial infarction, ischemic stroke, hospitalization for an acute coronary syndrome, or symptom-driven coronary or cerebral revascularization. The trial was stopped after a mean follow-up period of 3 years due to a lack of efficacy. At 2 years, niacin therapy had significantly raised HDL cholesterol levels (35 to 42 mg/dL), lowered triglycerides levels (164 to 122 mg/dL), and lowered LDL cholesterol levels (74 to 62 mg/dL); however, there was no significant difference in the primary endpoint between the two groups (16.4% niacin group to 16.2% placebo group; HR, 1.02; 95% CI, 0.87 to 1.21; P=0.79). There was a non-significant increase in the rate of ischemic stroke among patients in the extended-release niacin group over the placebo matched group (1.1% placebo and 1.7% niacin group; HR 1.61, 95% CI; 0.89 to 2.9, P=0.11). The authors note this may be due to statistical chance, but warrants further review. The authors concluded among patients with atherosclerotic cardiovascular disease and LDL cholesterol levels of less than 70 mg/dL, there was no incremental clinical benefit from the addition of niacin to statin therapy during the follow-up period, despite improvements in HDL cholesterol and triglyceride levels. However, whether there may be a benefit in high-risk cardiac patients or those whose LDL cholesterol levels are not well controlled with statins alone requires further study.

That’s it for this week’s Primecuts. Happy Holidays to all, and remember no Angry Birds during morning rounds.

Dr.  Jason Feliberti is a 1st year resident at NYU Langone Medical Center

Peer Reviewed by Robert Gianotti, MD, associate editor, Clinical Correlations

Image courtesy of Wikimedia Commons

References:

Richtel, Matt. “As Doctors Use More Devices, Potential for Distraction Grows.” NY Times 15 December 2011: A1. Print.  http://www.nytimes.com/2011/12/15/health/as-doctors-use-more-devices-potential-for-distraction-grows.html?pagewanted=all

Smith, T., Darling, E., Searles, B. 2010 Survey on cell phone use while performing cardiopulmonary bypass. Perfusion. 2011;26:375-380

Papadakos, PJ. “Electronic Distraction: An Unmeasured Variable in Modern Medicine.” Anesthesiology News. 2011;37:11

Carson, JL. Et. al. Liberal or Restrictive Transfusion in High-Risk Patients after Hip Surgery. NEJM. 2011 Dec 14 [Epub ahead of print].  http://www.nataonline.com/index.php?NumArticle=4657

Barr, PJ. Tranfusion Thresholds in FOCUS. NEJM. 2011 Dec 14 [Epub ahead of print] http://www.ncbi.nlm.nih.gov/pubmed/22168589

Carless PA, Henry DA, Carson JL, Hebert PPC, McClelland B, Ker K. Transfusion thresholds and other strategies for guiding allogeneic red blood cell transfusion. Cochrane Database Syst Rev 2010;10:CD002042-CD002042 https://www.lshtm.ac.uk/publications/list.php?inpress=1&filter=list&value=20238316&view=code

Hebert PC, Wells G, Blajchman MA, et al. A multicenter, randomized, controlled clinical trial of transfusion requirements in critical care. N Engl J Med 1999;340:409-417  http://www.nejm.org/doi/full/10.1056/NEJM199902113400601

AIM-HIGH Investigators. Niacin in patients with low HDL cholesterol levels receiving intensive statin therapy. NEJM. 2011;365(24):2255-67.