Daniel A. Pietro

Detecting and reporting medical errors: why the dilemma?

Errors in medicine are a major cause of harm to patients. Though there is little controversy among clinicians about the importance of accurate and reliable clinical data and the imperative of correct diagnosis, that commitment to exactitude dissolves when errors happen. Then, clinicians and managers may behave in a way that limits investigation. We often use the subjectivity and complexity of medicine to rationalise and justify error. Many factors explain this reluctance to investigate and to accept error. If we are to design effective systems to prevent errors from affecting patients, we must understand these factors. The following case study illustrates the concerns, fears, and practical problems that we faced in conducting an evaluation of misinterpreted prostate biopsies. #### Summary points Detection and prevention of errors are obvious goals for any organisation In reality, however, medicines approach to error has been limited and inadequate Motivational factors, both real and perceived, that influence how errors in medicine are handled must be identified, discussed, and changed if the “patient safety movement” isto succeed Our experience with misread prostate biopsies illustrates the concerns, fears, and practical problems encountered when dealing with the discovery of medical errors In February 1999 a urologist at the Sturdy Memorial Hospital in Attleboro, Massachusetts, requested a retrospective review of a 1996 biopsy result because of the patients clinical course and the results of a biopsy in 1999. The review revealed that the 1996 report was incorrect. The urologist and pathologist (neither of whom was responsible for the 1996 reading) implemented appropriate management for the affected patient. When they discovered a second misread prostate biopsy from the same period the urologist and pathologist became concerned that the frequency of these errors was higher than “expected.” Fears about malpractice suits and damaged reputations emerged. The potential ofa bigger problem meant risk to more …

Quantitative two-dimensional echocardiographic analysis of motion and thickening of the interventricular septum after cardiac surgery.

Septal and lateral wall motion and septal thickening were evaluated with quantitative two-dimensional echocardiography in 20 patients who underwent cardiac surgery without complications. Postoperative mean ejection fraction (48 +/- 10%) measured by radionuclide ventriculography was unchanged from the preoperative value (45 +/- 8%). Mean postoperative systolic thickening of the septum (33 +/- 15%) was also unchanged from the preoperative value (26 +/- 10%). However, septal endocardial motion as measured by an external frame-of-reference (fixed-axis) system fell from a 22 +/- 10% mean percent shortening (MPS) of septal radii to a postoperative value of -8 +/- 15% (p less than .001). Fixed-axis analysis also led to an increase in MPS of lateral radii: preoperative 16 +/- 5%; postoperative 28 +/- 9% (p less than .001). With an internal frame-of-reference (floating-axis) system, which compensates for the effects of translation and rotation on wall motion, postoperative MPS of septal radii (22 +/- 10%) was unchanged from preoperative MPS (25 +/- 8%; p = NS). Similarly, MPS of lateral wall radii was unchanged (preoperative, 15 +/- 5%; postoperative, 12 +/- 5%; p = NS). Thus systolic translation of the ventricle accounts for abnormal postoperative septal motion seen in a fixed-axis system and can be corrected by a floating-axis system. These data have important implications for the noninvasive evaluation of regional wall motion after cardiac surgery. Systems using a fixed external frame of reference such as radionuclide ventriculography are prone to systematic error. A combination of systolic thickening analysis by two-dimensional echocardiography and analysis of endocardial motion by the floating-axis system is a more appropriate method for evaluating the effects of cardiac surgery on regional left ventricular function.

Effects of simvastatin and probucol in hypercholesterolemia (simvastatin multicenter study group II)

This 12-week, randomized, double-blind, multicenter study compared the efficacy, tolerability and safety of simvastatin (a potent HMG-CoA reductase inhibitor) and probucol. Two doses of simvastatin, 20 or 40 mg once daily, were compared to probucol, 500 mg twice daily. Both simvastatin doses were significantly more effective than probucol in improving the plasma lipid profile. Mean reduction in low density lipoprotein (LDL) cholesterol was 34% with 20-mg simvastatin and 40% with the 40-mg dosage, compared to a mean reduction of 8% with probucol. Simvastatin significantly decreased total cholesterol, triglycerides and apolipo-protein B, and increased high density lipoprotein (HDL) cholesterol and apolipoprotein A-I. Probucol caused some reduction in LDL cholesterol but significantly decreased HDL cholesterol. Both simvastatin and probucol were well tolerated and no serious drug-related events occurred. Simvastatin appears to be a well-tolerated and effective new agent used once-a-day as an adjunct to diet in the management of patients with hypercholesterolemia.

Intracardiac masses. Tumors, vegetations, thrombi, and foreign bodies.

Echocardiography has enhanced our diagnostic capability in the detection of cardiac myxomas and, to some degree, metastatic tumor. It has assisted in the evaluation and treatment of certain patients with infective endocarditis and now appears to be providing insight into the recognition and course of some cases of intracardiac thrombosis. However, the limitations in the latter conditions are still significant and careful interpretation and clinical correlation should be the rule.