Tuesday, November 24, 2015

How sick are our sepsis patients? Not as sick as our coding says they are!

There's been a push for “improved” coding in the last few years. Purported benefits include better accuracy in the medical record and improved quality of research that is drawn from administrative databases. The real effect of today's coding trends, as many of us already know on the ground, has been quite the opposite as illustrated in this recent study which looked at septic patients:


We assessed trends from 2005 to 2013 in the annual sensitivity and incidence of discharge ICD-9-CM codes for organ dysfunction (shock, respiratory failure, acute kidney failure, acidosis, hepatitis, coagulopathy, and thrombocytopenia) relative to standardized clinical criteria (use of vasopressors/inotropes, mechanical ventilation for greater than or equal to 2 consecutive days, rise in baseline creatinine, low pH, elevated transaminases or bilirubin, abnormal international normalized ratio or low fibrinogen, and decline in platelets)...


Acute organ dysfunction codes were present in 57,273 of 191,695 (29.9 %) hospitalizations with suspected infection, most commonly acute kidney failure (60.2 % of cases) and respiratory failure (28.9 %). The sensitivity of all organ dysfunction codes except thrombocytopenia increased significantly over time. This was most pronounced for acute kidney failure codes, which increased in sensitivity from 59.3 % in 2005 to 87.5 % in 2013 relative to a fixed definition for changes in creatinine (p = 0.019 for linear trend). Acute kidney failure codes were increasingly assigned to patients with smaller creatinine changes: the average peak creatinine change.. The mean number of dysfunctional organs in patients with suspected infection increased from 0.32 to 0.59 using discharge codes versus 0.69 to 0.79 using clinical criteria (p less than 0.001 for both trends and comparison of the two trends). The annual incidence of hospitalizations with suspected infection and any dysfunctional organ rose an average of 5.9 % per year (95 % CI 4.3, 7.4 %) using discharge codes versus only 1.1 % (95 % CI 0.1, 2.0 %) using clinical criteria.


Coding for acute organ dysfunction is becoming increasingly sensitive and the clinical threshold to code patients for certain kinds of organ dysfunction is decreasing. This accounts for much of the apparent rise in severe sepsis incidence and severity imputed from claims.

Among the motivations for this more aggressive coding are the potential for hospitals to get paid more under the prevailing crazy DRG scheme and improved public report cards for doctors, which are severity adjusted, based on codes.

The result is that research based on administrative databases is becoming increasingly suspect and public report cards are nearly meaningless. The consumer public doesn't know this but it probably doesn't matter given research that they largely ignore public reporting.

Monday, November 23, 2015

Review article: cholangiopathies

Cholangiocytes (ie, the epithelial cells that line the bile ducts) are an important subset of liver cells. They are actively involved in the modification of bile volume and composition, are activated by interactions with endogenous and exogenous stimuli (eg, microorganisms, drugs), and participate in liver injury and repair. The term cholangiopathies refers to a category of chronic liver diseases that share a central target: the cholangiocyte. The cholangiopathies account for substantial morbidity and mortality given their progressive nature, the challenges associated with clinical management, and the lack of effective medical therapies. Thus, cholangiopathies usually result in end-stage liver disease requiring liver transplant to extend survival. Approximately 16% of all liver transplants performed in the United States between 1988 and 2014 were for cholangiopathies. For all these reasons, cholangiopathies are an economic burden on patients, their families, and society. This review offers a concise summary of the biology of cholangiocytes and describes a conceptual framework for development of the cholangiopathies. We also present the recent progress made in understanding the pathogenesis of and how this knowledge has influenced therapies for the 6 common cholangiopathies—primary biliary cirrhosis, primary sclerosing cholangitis, cystic fibrosis involving the liver, biliary atresia, polycystic liver disease, and cholangiocarcinoma—because the latest scientific progress in the field concerns these conditions.

Sunday, November 22, 2015

Catastrophic thrombotic syndromes

This designation was formerly termed thrombotic storm. The new terminology recognizes that this is a group of disorders with a common phenotype. An updated free full text review can be found here in Blood's How I Treat series. From the abstract of the paper:

Catastrophic thrombotic syndromes are characterized by rapid onset of multiple thromboembolic occlusions affecting diverse vascular beds. Patients may have multiple events on presentation, or develop them rapidly over days to weeks. Several disorders can present with this extreme clinical phenotype, including catastrophic antiphospholipid syndrome (APS), atypical presentations of thrombotic thrombocytopenic purpura (TTP) or heparin-induced thrombocytopenia (HIT), and Trousseau syndrome, but some patients present with multiple thrombotic events in the absence of associated prothrombotic disorders. Diagnostic workup must rapidly determine which, if any, of these syndromes are present because therapeutic management is driven by the underlying disorder. With the exception of atypical presentations of TTP, which are treated with plasma exchange, anticoagulation is the most important therapeutic intervention in these patients. Effective anticoagulation may require laboratory confirmation with anti–factor Xa levels in patients treated with heparin, especially if the baseline (pretreatment) activated partial thromboplastin time is prolonged. Patients with catastrophic APS also benefit from immunosuppressive therapy and/or plasma exchange, whereas patients with HIT need an alternative anticoagulant to replace heparin.

Saturday, November 21, 2015

The ongoing controversy over cholesterol and statins

A provocative article in the World Journal of Cardiology challenges some simplistic assumptions.

Below are a few of the points made in the article.

Total cholesterol is a poor predictor of risk

This has been known for decades. The authors cite findings from the Framingham study in which total cholesterol levels in patients with coronary disease overlap highly with levels in patients free of coronary disease. That is illustrated in this figure. But to say these findings negate the cholesterol hypothesis ignores the distinction between population attributable risk and relative risk. The findings, despite a well documented correlation between cholesterol levels and coronary disease risk, are explained by the multitude of other factors, in addition to cholesterol levels, that contribute to risk. Other factors must be taken into account and in the Framingham study the ratio of total cholesterol to HDL was a strong predictor.

In multiple clinical trials dietary interventions aimed primarily at reducing cholesterol levels failed to impact coronary disease outcomes

Diet trials may have been confounded by increased carbohydrate intake which activated the metabolic syndrome phenotype in many patients. On the other hand, cholesterol lowering drug trials have shown reductions in events. This is not just due to pleiotropic effects of statins, as there is evidence from non statin cholesterol lowering drug trials of event reduction.

Interventions to reduce risk need to be viewed in perspective

For example: cholesterol lowering diets have not been proven to reduce events; statins achieve a relative risk reduction of about 30%; the Mediterranean has been reported to achieve a 70% relative risk reduction.

Though a risk factor, a singular focus on cholesterol reduction is misguided

Carotid doppler flow measurements

---to assess volume responsiveness.

Friday, November 20, 2015

The heart in Duchenne and Becker muscular dystrophy

Free full text review.  From the article:

To conclude, heart involvement is common in both DMD/BMD and female carriers. Serial cardiac evaluation, including clinical examination, ECG, Holter monitoring, echocardiographic and CMR study, is the “sine qua non” for this population. Early detection of heart involvement should motivate early cardiac treatment with ACE inhibitors and b-blockers to delay serious cardiac complications.

Calcium blocker overdose

There is a spectrum of management options based on severity, starting with general supportive measures and progressing through modalities such as high dose insulin with glucose, lipid rescue and ECMO. Here is a mini-lecture from the Mayo EMBlog.

Thursday, November 19, 2015

Bundled payments: will they help?

A recent paper in Circulation looked at bundled payments for health care. The focus was on cardiovascular disease which has been a major target of criticism for over utilization. In addition, the cardiovascular service line has probably accumulated more experience in bundled payment than other specialities.

The article, despite making some unwarranted claims and confusing the terminology of health care does make some valid points and is worth the read.

In general, bundling of payments tends to bring costs down. What is most desirable in health care, of course, is adherence to evidence based medicine. The perfect world would be one in which all providers practiced perfect evidence based medicine 100% of the time. The appropriate question then, is, what would perfect adherence to EBM do to health care costs? Despite the claims of many policy experts, we don't know whether it would decrease costs, have a neutral effect or even increase costs. Abundant literature suggests that departure from evidence based medicine comes in the form of both over utilization and under utilization.

The discussion in the article, as do many discussions of health care today, centers around the contrast between fee for service medicine and the various models of bundled payment and characterizes health care in the US as being fee for service. That is simplistic, because inpatient care is under the Prospective Payment System (DRGs) is not fee for service. In the US the situation is complex and we operate under a variety of incentives. The assumption that one incentive is better than another dominates much of the discussion. However, any time someone does health care for a living, no matter the particular incentive, a conflict exists. Fee for service medicine creates a positive cost incentive. Bundled payments provide negative incentives. Who's to say which is better for patients? There's room for vigorous debate.

The first paragraph of the article reads:

Episode-based, “bundled” payments have come to the forefront of the national discussion on combating rising healthcare costs. In the currently dominant fee-for-service model for reimbursement, hospitals, physicians, and postacute care providers file distinct claims and are paid separately for provided services even when they are related to a single episode of care. However, this approach to payment encourages fragmented care, with little incentive for resource stewardship, coordination, or communication across multiple providers. In contrast, bundled payments seek to align the interests of providers..

Aside from the incorrect implication that hospitals are under fee for service reimbursement what about the alignment of interests that bundling purports to achieve? Under fee for service payment individual providers fight with the payer for reimbursement. Under bundled payment the fight is with each other for a piece of the pie. What kind of alignment is that?

The paper addresses the evidence on bundling. In short, it is preliminary. We do have experience to draw on from Medicare's Prospective Payment System but the newer models under discussion today are largely in experimental stages. A few cautions statements can be made. In general bundled systems seem to curb the rate of cost increases. The effect is modest. In the case of Medicare's Prospective Payment System the cost savings have been counterbalanced by a shift to outpatient treatment which is still largely paid on the fee for service model. This can be viewed as an escape valve from the negative cost incentives so that hospitals can survive. It has resulted in shorter hospital stays and that may have caused increased readmission rates.

These concluding remarks from the paper are correct:

Given this mixed picture of the evidence, it is important to place bundled payments in an appropriate context. On one hand, the future of bundled payments remains largely uncertain.

A number of bundled payment models are now under investigation as pilot projects by the Center for Medicare and Medicaid Innovation. Which of these will see mainstream implementation, if any, and when, is unknown.

Brain abscess

A review in Neurohospitalist. Free full text.