1/27. Aneurysm rupture after endovascular repair using the AneuRx stent graft.OBJECTIVE: The purpose of this study was to determine the cause and frequency of aneurysm rupture after endovascular aneurysm repair. methods: We reviewed each patient who sustained aneurysm rupture among all patients enrolled for endovascular aortic aneurysm repair in phases I, II, and III of the US AneuRx Multicenter clinical trial from June 1996 through October 1999. RESULTS: A total of 1067 patients were enrolled for endovascular aneurysm repair. The AneuRx stent graft was successfully implanted in 1046 patients (98%). Endovascular repair was unsuccessful in 21 patients (2%); 13 patients (1%) were converted to open aneurysm repair. Among these, two patients (0.2%) sustained aneurysm rupture due to procedure-related instrumentation and underwent open surgical conversion. Aneurysm rupture has occurred in seven patients (0.7%) 3 weeks to 24 months (mean, 16 months) after successful endovascular repair. Four patients survived open surgical repair, and three patients died within 30 days. overall rupture-related mortality was 0.5% and included late deaths after rupture. Before rupture, two patients had endoleak and aneurysm enlargement, and five patients had no endoleak and no aneurysm enlargement. After aneurysm rupture all seven patients had evidence suggesting that there was poor fixation of the stent graft at the proximal distal, or iliac junction fixation sites. The two patients with endoleak declined recommended open surgical or endovascular repair, which could have prevented aneurysm rupture. In retrospect, the five patients without endoleak could potentially have avoided rupture with better patient selection, better stent graft positioning, or reinforcement of fixation points with stent graft extenders. The probability of no aneurysm rupture for all patients undergoing endovascular repair is 0.996 /- 0.002 at 1 year and 0.974 /- 0.011 at 2 years by life table analysis with the longest follow-up of 41 months. CONCLUSION: The early risk of aneurysm rupture after endovascular aneurysm repair is low. However, the possibility of rupture persists even in patients with no endoleak after the procedure. Therefore, all patients treated with endovascular aneurysm repair should continue to be monitored after the procedure. patients with evidence suggesting insecure stent graft fixation should undergo further endovascular treatment or open surgical repair.- - - - - - - - - - ranking = 1keywords = probability (Clic here for more details about this article) |
2/27. fluconazole-induced torsade de pointes.OBJECTIVE: To present a case of fluconazole-associated torsade de pointes (TDP) and discuss fluconazole's role in causing TDP. CASE SUMMARY: A 68-year-old white woman with candida glabrata isolated from a presacral abscess developed TDP eight days after commencing oral fluconazole The patient had no other risk factors for TDP, including coronary artery disease, cardiomyopathy, congestive heart failure, and electrolyte abnormalities There was a temporal association between the initiation of fluconazole and TDP. The TDP resolved when fluconazole was discontinued; however, the patient continued to have premature ventricular contractions and nonsustained ventricular tachycardia (NSVT) until six days after drug cessation DISCUSSION: Use of the Naranjo probability scale indicates a probable relationship between the use of fluconazole and the development of TDP. The possible mechanism is depression of rapidly activating delayed rectifier potassium currents. In our patient, there was no other etiology identified that could explain QT prolongation or TDP The complete disappearance of NSVT and premature ventricular contractions followed by normalization of QT interval after the drug was stopped strongly suggests fluconazole as the etiology. CONCLUSIONS: Clinicians should be aware that fluconazole, even at low doses, may cause prolongation of the QT interval, leading to TDP. Serial electrocardiographic monitoring may be considered when fluconazole is administered in patients who are at risk for ventricular arrhythmias.- - - - - - - - - - ranking = 1keywords = probability (Clic here for more details about this article) |
3/27. Quantification of F-18 FDG PET images in temporal lobe epilepsy patients using probabilistic brain atlas.A probabilistic atlas of the human brain (Statistical Probabilistic Anatomical maps: SPAM) was developed by the international consortium for brain mapping (ICBM). It is a good frame for calculating volume of interest (VOI) in many fields of brain images. After calculating the counts in VOI using the product of probability of SPAM images and counts in FDG images, asymmetric indices (AI) were calculated and used for finding epileptogenic zones in mesial temporal lobe epilepsy (mTLE). FDG PET images from 18 surgically confirmed mTLE patients and 22 age-matched controls were spatially normalized to the average brain MRI template of ICBM. Counts from normalized PET images were multiplied with the probability of 12 VOIs from SPAM images in both temporal lobes. Finally AI were calculated on each pair of VOIs, and compared with visual assessment. If AI of mTLE patients were not within 2.9 standard deviation from those of normal control group (P < 0.008; Bonferroni correction for P < 0.05), epileptogenic zones were considered to be found successfully. The counts of VOIs in the normal control group were symmetric (AI < 4.3%, paired t test P > 0.05) except for those of the inferior temporal gyrus (P < 0.001). By AIs in six pairs of VOIs, PET in mTLE had deficit on one side (P < 0.05). Lateralization was correct in only 14/18 of patients by AI, but 17/18 were consistent with visual inspection. In three patients with normal AI, PET images were symmetric on visual inspection. The asymmetric indices obtained by taking the product of the statistical probability anatomical map and FDG PET, correlated well with visual assessment in mTLE patients. SPAM is useful for the quantification of VOIs in functional images.- - - - - - - - - - ranking = 3keywords = probability (Clic here for more details about this article) |
4/27. probability matching in the right hemisphere.Previously it has been shown that the left hemisphere, but not the right, of split-brain patients tends to match the frequency of previous occurrences in probability-guessing paradigms (Wolford, Miller, & Gazzaniga, 2000). This phenomenon has been attributed to an "interpreter," a mechanism for making interpretations and forming hypotheses, thought to reside exclusively in the left hemisphere. In this study with a split-brain patient, we had him guess one of two types of faces, stimuli known to be preferentially processed in the right hemisphere of this patient. Unlike previous studies using other kinds of stimuli, the right hemisphere matched the frequency of the previous occurrences of a face-type, but the left hemisphere did not.- - - - - - - - - - ranking = 1keywords = probability (Clic here for more details about this article) |
5/27. Acute renal failure associated with vancomycin- and tobramycin-laden cement in total hip arthroplasty.OBJECTIVE: To describe 2 cases of acute renal failure (ARF) associated with the use of antibiotic-laden cement incorporated in total hip arthroplasties (THA). CASE SUMMARIES: An 82-year-old female received a right THA with antibiotic-laden cement spacers. She developed ARF 5 months following implantation, concurrent with an elevated serum tobramycin concentration of 5.5 microg/mL. After explantation of the prosthesis and spacers, serum creatinine and antibiotic concentrations decreased to within normal limits. A 79-year-old male received antibiotic-laden cement spacers in a revision of his right THA due to infection. ARF developed 1 1/2 months after the revision; a serum tobramycin concentration was 2.9 microg/mL. Serum creatinine and antibiotic serum concentrations decreased to within normal limits with explantation. DISCUSSION: More than 250 000 joint replacements are performed yearly in the US. A common complication is infection, which occurs in 1-2% of primary replacements and 3-4% of revisions of previously infected prostheses. Antibiotic-laden cement is used for prosthesis placement to prevent or treat infection, while minimizing systemic drug exposure. Both patients described here received antibiotic-laden spacers during THA and subsequently developed ARF in conjunction with elevated serum tobramycin concentrations. Use of the Naranjo probability scale and consideration of possible contributing factors suggest a probable association of the antibiotic-laden cement and the development of ARF in these patients. CONCLUSIONS: Antibiotic-laden cement with aminoglycosides and/or vancomycin has the potential for systemic toxicity and should be used according to guidelines and with increased vigilance and prudent monitoring in patients at increased risk for nephrotoxicity.- - - - - - - - - - ranking = 1keywords = probability (Clic here for more details about this article) |
6/27. Complications of cerebrospinal fluid shunt antisiphon devices.The case histories of 38 children with implanted antisiphon devices (ASD) were retrospectively reviewed. Sixty-three percent suffered a shunt malfunction within 5 years of ASD implantation. The probability of shunt malfunction within 1 year was of 40%. patients with myelomeningocele experienced the highest rate of malfunction. Age, order of ASD implantation (whether implanted primarily or secondarily), shunt pressure, and reason for ASD insertion did not significantly alter the incidence of malfunction. Fifty percent of the shunt complications were specifically related to ASD malfunction. Functional obstruction of the shunt system as determined by evidence of clinical shunt obstruction with documented patency on shunt flow testing occurred in 10 of 38 patients. No variable studied could be significantly related to the probability of developing an ASD-related complication. Functional obstruction of the ASD is a common and unpredictable complication of these devices.- - - - - - - - - - ranking = 2keywords = probability (Clic here for more details about this article) |
7/27. Joint replacement for ankylosed hips.Forty-one fused hips in thirty-eight patients were converted to total hip replacement. The average length of follow-up was seven years. The predominant indications for conversion were progressively disabling pain in the low back or the hip, or both; loss of function due to immobility or malposition of the hip; and progressive pain and instability of the knee (usually ipsilateral). The postoperative arc of flexion averaged 87 degrees. Limb-length discrepancies improved an average of 2.5 centimeters. Postoperative function of the abductor muscles depended on the preoperative quality of those muscles and on the accuracy of the biomechanical restoration. Postoperative strength of the muscles of the hip improved for two years or more in most patients. There was complete or major relief of pain, improved mobility of the hip, and decreased dependence on supports for walking. There were nine failures: four because of sepsis, four because of loosening of the femoral component, and one because of malposition of the acetabular component. The failures were predominantly in patients who were fifty years old or less at the time of arthroplasty, patients who had had two or more previous operations, and patients who had had an injury to the hip. The quality of the results approached that after primary hip arthroplasty in older patients who have not had multiple previous operations on the hip. Survivorship analysis of the spontaneously fused hips that were treated with conventional hip replacement predicted a probability of survival of the implant of 96 per cent at thirteen years postoperatively (p = 0.048).- - - - - - - - - - ranking = 1keywords = probability (Clic here for more details about this article) |
8/27. Estimating mortality risk in preoperative patients using immunologic, nutritional, and acute-phase response variables.We measured the delayed type hypersensitivity (DTH) skin test response, along with additional variables of host immunocompetence in 245 preoperative patients to determine which variables are associated with septic-related deaths following operation. Of the 14 deaths (5.7%), 12 were related to sepsis and in 2 sepsis was contributory. The DTH response (p less than 0.00001), age (p less than 0.0002), serum albumin (p less than 0.003), hemoglobin (p less than 0.02), and total hemolytic complement (p less than 0.03), were significantly different between those who died and those who lived. By logistic regression analysis, only the DTH skin test response (log likelihood = 41.7, improvement X2 = 6.24, p less than 0.012) and the serum albumin (log likelihood = 44.8, improvement X2 = 17.7, p less than 0.001) were significantly and independently associated with the deaths. The resultant probability of mortality calculation equation was tested in a separate validation group of 519 patients (mortality = 5%) and yielded a good predictive capability as assessed by (1) X2 = 0.08 between observed and expected deaths, NS; (2) Goodman-Kruskall G statistic = 0.673) Receiver-Operating-Characteristic (ROC) curve analysis with an area under the roc curve, Az = 0.79 /- 0.05. We conclude that a reduced immune response (DTH skin test anergy) plus a nutritional deficit and/or acute-phase response change are both associated with increased septic-related deaths in elective surgical patients.- - - - - - - - - - ranking = 1keywords = probability (Clic here for more details about this article) |
9/27. Intracerebral malignant fibrous histiocytoma at site of a previously excised low grade glioma.The case of a 42-year-old patient is reported who developed an intracerebral malignant fibrous histiocytoma at the site of an oligoastrocytic mixed glioma which had been excised 2 1/2 years previously. Reasons for the extreme rarity of intracranial malignant fibrous histiocytomas, the probability of a traumatic aetiology of this particular tumour, and the possible significance of intratumoural cells positive for glial fibrillary acidic protein (GFAP) are discussed.- - - - - - - - - - ranking = 1keywords = probability (Clic here for more details about this article) |
10/27. Poor oxygenation in the lungs of patients with hyperosmolar hyperglycemic non-ketotic diabetic coma after cardiac surgery.The ratio of PaO2 to FiO2 was often low (300 or less) in four patients with complications of hyperosmolar hyperglycemic non-ketotic diabetic coma (HHNKDC) following open heart surgery. Four of our patients had poor oxygenation and subsequent spontaneous recovery from in the immediate post-operative period, although HHNKDC occurred only in one during this period. In the 3 others, poor oxygenation without accompanying HHNKDC lasted for 1-6 days and HHNKDC developed about 2 weeks after open heart surgery at time when poor oxygenation reoccurred. If a working diagnosis of congestive heart failure was made only on the basis of the most common probability, and the fluid supply was restricted, HHNKDC would readily occur or be aggravated by the dehydration iatrogenically produced. It is thus concluded that HHNKDC should be included in diagnoses for pulmonary dysfunction.- - - - - - - - - - ranking = 1keywords = probability (Clic here for more details about this article) |
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