DB'S MEDICAL RANTS

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Key to Excellence in General Practice

More on the Medicare bill

These links are provided for those who want a broad view of the new Medicare legislation. The breadth offered reflects our uncertainty concerning many provisions of the bill.

  • Medicare Plan for Competition Faces Hurdles – which suggests that we may never have the competitive options available – and explains why
  • Holding Down Drug Prices
  • Beyond Medicare reform

On pulmonary artery catheters

from The Arc of the Pulmonary Artery Catheter (paid subscription required)

In the 1980s, observational studies of patients with acute coronary syndromes distinctly challenged the utility and safety of this intervention, suggesting higher mortality for patients receiving a PAC. In 1996, a retrospective observational study of 5735 critically ill patients suggested that the PAC was associated with increased mortality and increased costs of care, even after adjusting for the propensity to receive catheterization. In 2000, a large retrospective observational study of 10 217 patients showed that use of the PAC was independently associated with admission to a surgical ICU, care delivered by a nonintensivist, patient race, and private insurance coverage. In 2001, a prospective observational study of 4059 patients undergoing major elective noncardiac surgery reported that those patients treated with a PAC had a 3-fold increase in major postoperative cardiac events.

Together, these publications had important consequences. They generated debate about whether patients should be managed with a PAC and why. They raised awareness about how in nonexperimental studies potentially inadequately adjusted confounders could lead to spurious associations between the PAC and poor clinical outcomes. They challenged us to step back and critically evaluate the PAC in terms of patient populations mostly likely to benefit. It became better understood that a diagnostic and monitoring device cannot improve clinical end points unless the therapy based on data from that device is itself effective. It was no longer just about the information obtained from the PAC?what was done with the data matters. An editorial accompanying the provocative study by Connors et al called (again) for a moratorium on the PAC or more randomized trials to test its effect on patient outcomes.

This quote comes from an editorial about the following article. Early Use of Pulmonary Artery Catheter Offers Neither Harm Nor Benefit

From Jan. 30, 1999, to June 29, 2001, 676 patients aged 18 years or older meeting standard criteria for shock, ARDS, or both were enrolled from 36 intensive care units in France and randomized to receive a PAC or not to receive it. Other management treatment was left to the discretion of the treating physician. Both groups were similar at baseline.

There were no significant differences between groups in the primary end point of mortality at 28 days (59.4% vs. 61.0%), nor in the secondary end points including mortality at day 14 (49.9% vs. 51.3%) and day 90 (70.7% vs. 72.0%). At day 14, the groups did not differ in number of days free of organ system failures, renal support, and use of vasoactive agents. At day 28, there were no significant differences between groups in days in hospital, days in the intensive care unit, or days of mechanical ventilation use.

“Clinical management involving the early use of a PAC in patients with shock, ARDS, or both did not significantly affect mortality and morbidity,” the authors write. “An influence on prognosis without goal-oriented therapy could only be suggested when the presence of a PAC results in significant changes in treatment with fluid loading and vasoactive agents…. Our results, which do not preclude the potential impact of a goal-oriented therapy with a PAC, strengthen the suggestion of the consensus statement made by the National Heart, Lung, and Blood Institute and the Food and Drug Administration that a randomized clinical trial with this design can be ethically performed in this population of critically ill patients.”

So back to the editorial –

Some questions about the safety of the PAC remain. Richard et al reported 17 arterial punctures, 1 hemothorax, 60 patients with arrhythmias, 6 patients with catheter knots, 8 patients with signs of exit site infection and sepsis, and 2 with positive catheter cultures. However, it does not appear that systematic screening for complications was undertaken in both groups. Complications possible in both groups such as arterial punctures may not have been recorded as well in the control group vs the PAC group; therefore, reported complications may be underestimated overall and inflated in terms of their difference between the 2 groups. For all devices like the PAC, harm associated with catheter insertion and management may vary among physicians, underscoring how operator-dependent complications in device trials are the study outcomes least generalizable to other settings.

I became a skeptic concerning pulmonary artery catheters from reading Dr. Connors work, and discussing his study with him. This article while not revealing any major harm, also does not give me a reason to request pulmonary artery catheterization. We must look further to understand whether this technology has any benefit.

The results of this multicenter randomized controlled clinical trial of the PAC in patients with shock, ARDS, or both may lead to more than one interpretation. The PAC was not associated with increased mortality or morbidity; however, neither was it associated with improved clinical outcomes. This trial and other studies provide reassurance that further investigation into the role of the PAC is feasible, likely safe, and should proceed forthwith. Even larger trials may be needed to more definitively evaluate this technology. A complementary approach is selection of specific patient populations to test protocolized treatment schedules based on data obtained from the PAC. Intensivists eagerly await the completion of 2 ongoing studies that champion these different designs: the UK National Health Service sponsored study Pulmonary Artery Catheters in Patient Management in Intensive Care (PAC-Man) and the recently resumed National Heart, Lung, and Blood Institute?sponsored Fluids and Catheters Treatment Trial (FACTT) of the ARDSNet.

Critical care medicine is well poised to build on its solid foundation of pathophysiological research and technology development with collaborative multicenter clinical investigations. These complementary approaches to inquiry are needed to help physicians better understand the risk:benefit, effort:yield, and cost:benefit of the PAC, as well as other old and new interventions used to care for the most seriously ill hospitalized patients in the ICU.

For now I remain skeptical.

Surgeons with great volume get better results

Surgeon Caseload Largely Explains Hospital Volume Link to Mortality

Numerous reports have shown that operative mortality is lower at hospitals with high procedural volumes. Now, new research suggests that this association is largely mediated by the caseload of the operative surgeon.

Therefore, a patient undergoing surgery at a low-volume hospital by a high-volume surgeon could have a better outcome than one undergoing surgery at a high-volume hospital by a low-volume surgeon. The relative importance of surgeon volume depends on the particular procedure, according to the report published in the November 27th issue of The New England Journal of Medicine.

For example, mortality with aortic-valve surgery is almost entirely related to surgeon volume. So, in this case, selecting an experienced surgeon may be more important than choosing a high-volume hospital. In contrast, mortality with lung resection did not appear to be closely related to surgeon volume, so selecting a high-volume hospital may be more critical.

“Our findings are really surprising to me and to many who’ve followed this area carefully,” lead author Dr. John D. Birkmeyer told Reuters Health. “ For years, the assumption was that hospital volume mattered a lot more than the volume of the operating surgeon. Our study really didn’t find that to be true.

This article argues for referring patients to surgeons who have great experience with a specific type of surgery. The data make sense, as the task is difficult, fraught with many hazards, and experience should give one a better “check list” to use during surgery. I suspect that the same is true (to a less dramatic effect) for many medical conditions. As a general internist, I would never try to give chemotherapy – I just do not have the volume to keep up with changes in the field.

Studies have shown that among generalists, specialoids (those who focus on a disease or system without advanced training) have better outcomes. We suspect those better outcomes occur because volume leads to experience which leads to a better understanding of the nuances of care.

These findings do not argue against the importance of generalists. Generalists can (and do) care very well for most common diseases. For example, type II diabetes mellitus is so common that we should have a large enough volume to have excellence. Similarly experience occurs with coronary artery disease, congestive heart failure, dyspepsia, chronic obstructive lung disease, hypertension as several examples.

The truly excellent generalist will become an expert at caring for the most common diseases and retain expertise in diagnosing the great majority of complaints. Part of our excellence comes from knowing when we do need to refer. We must all beware the error of not referring when indicated.

I find the findings of this article sobering. Perhaps we should evolve our health system in ways which take these findings into consideration. Interestingly, the durrent issue of JAMA considers this problem – Regionalization of High-Risk Surgery and Implications for Patient Travel Times (paid subscription required). The essence of the article:

With low-volume standards (1/year for pancreatectomy; 2/year for esophagectomy), approximately 15% of patients would change to higher-volume centers, with negligible effect on their travel times. Most patients would need to travel less than 30 additional minutes (74% pancreatectomy; 76% esophagectomy). Many patients already lived closer to a higher-volume hospital (25% pancreatectomy; 26% esophagectomy). Conversely, with very high-volume standards (>16/year for pancreatectomy; >19/year for esophagectomy), approximately 80% of patients would change to higher-volume centers. More than 50% of these patients would increase their travel time by more than 60 minutes. Travel times would increase most for patients living in rural areas.

These findings challenge us to consider the trade off between inconvenience and outcomes. I do not think it a difficult decision.

Anecdotally, most physicians who have complex disease (especially cancers) travel almost any distance to find the specialist for that disease. What do physicians know?

Surgeons with great volume get better results

Surgeon Caseload Largely Explains Hospital Volume Link to Mortality

Numerous reports have shown that operative mortality is lower at hospitals with high procedural volumes. Now, new research suggests that this association is largely mediated by the caseload of the operative surgeon.

Therefore, a patient undergoing surgery at a low-volume hospital by a high-volume surgeon could have a better outcome than one undergoing surgery at a high-volume hospital by a low-volume surgeon. The relative importance of surgeon volume depends on the particular procedure, according to the report published in the November 27th issue of The New England Journal of Medicine.

For example, mortality with aortic-valve surgery is almost entirely related to surgeon volume. So, in this case, selecting an experienced surgeon may be more important than choosing a high-volume hospital. In contrast, mortality with lung resection did not appear to be closely related to surgeon volume, so selecting a high-volume hospital may be more critical.

“Our findings are really surprising to me and to many who’ve followed this area carefully,” lead author Dr. John D. Birkmeyer told Reuters Health. “ For years, the assumption was that hospital volume mattered a lot more than the volume of the operating surgeon. Our study really didn’t find that to be true.

This article argues for referring patients to surgeons who have great experience with a specific type of surgery. The data make sense, as the task is difficult, fraught with many hazards, and experience should give one a better “check list” to use during surgery. I suspect that the same is true (to a less dramatic effect) for many medical conditions. As a general internist, I would never try to give chemotherapy – I just do not have the volume to keep up with changes in the field.

Studies have shown that among generalists, specialoids (those who focus on a disease or system without advanced training) have better outcomes. We suspect those better outcomes occur because volume leads to experience which leads to a better understanding of the nuances of care.

These findings do not argue against the importance of generalists. Generalists can (and do) care very well for most common diseases. For example, type II diabetes mellitus is so common that we should have a large enough volume to have excellence. Similarly experience occurs with coronary artery disease, congestive heart failure, dyspepsia, chronic obstructive lung disease, hypertension as several examples.

The truly excellent generalist will become an expert at caring for the most common diseases and retain expertise in diagnosing the great majority of complaints. Part of our excellence comes from knowing when we do need to refer. We must all beware the error of not referring when indicated.

I find the findings of this article sobering. Perhaps we should evolve our health system in ways which take these findings into consideration.

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