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Eric Lim

Publications and source records attributed to Eric Lim.

At least 37 records · Page 2Linked to original sources
PubMed2005

The impact of stage and cell type on the prognosis of pulmonary neuroendocrine tumors.

OBJECTIVE: In pulmonary neuroendocrine tumors the realization that the extent of nodal disease is related to cell type has led to a controversy as to which is the dominant prognostic factor, stage or morphology. To clarify this relationship, we studied patients treated at our institution over a 23-year period. METHODS: This is a historical cohort study of patients with confirmed pulmonary neuroendocrine tumors who underwent lung resection from 1980 through 2003. Survivors were contacted by telephone, and recurrences were confirmed by means of histopathology. Cox proportional hazards regression was used to ascertain the joint influence of several risk factors on survival. RESULTS: The mean age of the cohort was 54 years (standard deviation, 15 years), and 100 (57%) were men. The cell types for the 177 eligible patients were typical carcinoid in 89 (50%), atypical carcinoid in 15 (8%), large cell in 22 (13%), and small cell in 51 (29%). The median time to follow-up was 7 years (first to third quartile, 2-12 years), and overall 5- and 10-year survivals were 86% (79%-90%) and 81% (74%-87%), respectively. The univariable predictors of survival were age (P = .001), nodal stage (P = .01), and cell type (P < .001). In the final multivariable model only age (P = .04) and cell type (P < .001) remained as independent predictors. The hazard of death among patients with large cell or small cell lung cancer was highest in the first year and a half after diagnosis, reducing drastically thereafter. CONCLUSIONS: In pulmonary neuroendocrine tumors cell type is the predominant determinant of survival. The survival of patients with each cell type is sufficiently diverse to warrant different management strategies. Conservative resection is feasible for typical carcinoids, but the effects of adjuvant chemotherapy need to be evaluated for the other subgroups.

Cohort Studies↗
PubMed2004

Determinants of successful endoscopic internal thoracic artery harvesting: a prospective analysis.

OBJECTIVE: Endoscopic internal thoracic artery (ITA) harvesting is employed during minimal-access coronary artery bypass grafting. To improve case selection, we prospectively analyzed our entire experience to identify variables that predict intraoperative conversion to sternotomy. METHODS: We performed a prospective study from September 1999 to November 2003 of 100 consecutive patients with an endoscopically harvested left ITA (LITA). Success was defined as an endoscopic dissection of the LITA sufficient to reach the anastomosis. Multivariate logistic regression analysis was performed to identify independent preoperative and procedural predictors of success. RESULTS: The measured parameters (mean +/- SD) were age (62 +/- 9 years), height (174 +/- 9 cm), weight (81 +/- 14 kg), and logistic Euroscore (2.0 +/- 1.7). Patients comprised 8 (8%) women, 17 (17%) with urgent operations, 42 (42%) with multiple vessel disease, 17 (17%) with a left ventricular ejection fraction <50%, 2 (2%) redo procedures, and 3 (3%) with pleural disease. The Zeus robot was used in 17 patients (17%). Eight-eight (88%) of the LITA were successfully harvested endoscopically. Among the 12 patients who underwent conversions, pleural adhesions were the most common finding (n = 4, 33%). One LITA was unusable. In the final multivariate model, lung disease was a negative predictor of successful endoscopic harvest (odds ratio, 0.13; 95% confidence interval, 0.02-0.63; P =.012). The variables of age, sex, left ventricular function, logistic Euroscore, operative priority, and use of the Zeus robot did not achieve statistical significance. CONCLUSIONS: Acceptable conversion rates and low conduit wastage are achievable during a unit's initial experience. Lung disease is associated with increased conversion frequency, and surgeons embarking on endoscopic harvesting should consider excluding these patients to improve their chances of success. Pleural adhesions increase the technical difficulty of surgery.

Coronary Artery Bypass↗
PubMed2004

Allogenic blood transfusion does not predispose to infection after cardiac surgery.

BACKGROUND: Many retrospective studies report increased postoperative infection after allogenic blood transfusion. To investigate this phenomenon, we prospectively studied 232 patients undergoing cardiac surgery. METHODS: Patients were screened daily for evidence of culture positive infections. Wounds were examined daily and defined on the ASEPSIS score. Chest radiographs and white cell counts and differentials were recorded on days 1, 2, and 4. The use of blood products was monitored blindly and independently. Patients were grouped according to transfusion status and compared using chi2 or Fisher's test. Logistic regression analyses were performed to identify predictors of transfusion and infection. RESULTS: Of 232 patients, 116 (50%) received blood product transfusion. Patients receiving blood had lower preoperative hemoglobin, were older, with a greater proportion of urgent/emergency or revision surgery, and were higher risk. Despite this, there were no differences in the frequency of chest infection (20% versus 15%, p = 0.38), urinary infection (3.5% versus 5.3%, p = 0 0.75), wound infection (3.5% versus 8.0%, p = 0.16), or overall infection (28% versus 30%, p = 0.89) comparing the transfused versus untransfused groups. There was no evidence to suggest that administration of blood products was associated with infection (odds ratio 0.92, p = 0.77). CONCLUSIONS: The administration of blood per se did not lead to increased postoperative infection. Clinicians should reconsider withholding blood transfusion in patients solely owing to concerns of predisposition to infection.

Aged↗
PubMed2004

Intraoperative pleural lavage cytology is an independent prognostic indicator for staging non-small cell lung cancer.

OBJECTIVES: For patients undergoing lung resection for cancer, macroscopic evidence of metastasis is clearly associated with adverse prognosis. However, less is known about the significance of tumor cells detected by using tests such as pleural lavage cytology. To ascertain the frequency and quantify the effect of this finding on survival, we performed a prospective study of intraoperative pleural lavage cytology. METHODS: Pleural lavage cytology consisted of cytologic analysis of 100 mL of saline irrigated over the lung surface immediately after thoracotomy. Patients were excluded if they had an existing effusion, extreme adhesions, or lateral chest wall invasion or if resection was not performed. Survival was calculated by means of Kaplan-Meier analysis and compared by using log-rank tests. Cox regression was used to ascertain independent predictors of prognosis. RESULTS: From 1995 through 2003, we performed pleural lavage cytology on 292 patients undergoing thoracotomy for lung cancer. The mean age was 64 (SD, 10) years, and 196 (67%) patients were men. Of 292 samples, 13 (4.5%) showed evidence of malignant cells. The median time to follow-up was 15 months (interquartile range, 1-40 months), with a median survival of 49 months for patients with negative pleural lavage cytology results and 13 months for patients with positive pleural lavage cytology results (P =.002). Univariate prognostic predictors were positive pleural lavage cytology status (P =.03), stage (P =.03), adenocarcinoma (P =.06), and parietal pleural involvement (P =.01). In the final multivariate model only positive pleural lavage cytology status (P =.006) and stage (P =.03) remained significant. CONCLUSIONS: Intraoperative pleural lavage cytology is a simple addition to intrathoracic staging and an independent predictor of prognosis. Positive results potentially affect survival by upstaging patients to stage IIIB or greater.

Adenocarcinoma↗
PubMed2004

Clopidogrel did not inhibit platelet function early after coronary bypass surgery: A prospective randomized trial.

OBJECTIVE: Although the beneficial effect of aspirin prescription after coronary surgery has been established, the efficacy of clopidogrel has never been compared with that of aspirin in the critical early postoperative period. We therefore conducted a prospective, double-blind, randomized controlled trial to compare the efficacies of these antiplatelet regimens. METHODS: Patients undergoing elective primary coronary artery bypass surgery were invited to participate. After the operation, patients were randomized to receive 100 mg aspirin, 325 mg aspirin, or 75 mg clopidogrel tablets daily for 5 days. Our primary outcome measure was platelet aggregation on day 5, expressed as percentage of baseline. Assessment of platelet aggregation was undertaken with the technique of Born. RESULTS: From September 2002 to July 2003, a total of 54 patients were randomized into the study. There were 2 self-withdrawals and 2 protocol violations, leaving 50 patients for analysis, 34 in the aspirin group and 16 in the clopidogrel arm. Compared with baseline, the mean percentage aggregations with collagen on day 5 were 56% for aspirin and 99% for clopidogrel. The mean difference between the two arms was 42% (95% confidence interval 27%-56%) in favor of aspirin. At the same time point, the effective concentration to inhibit 50% aggregation in the samples from patients randomly assigned to receive clopidogrel were not raised for our entire panel of agonists (changes of -0.04 microg/L for collagen, -0.01 micromol/L for epinephrine, and -0.02 micromol/L for adenosine diphosphate). CONCLUSION: Clopidogrel, unlike aspirin, did not inhibit platelet aggregation in the first 5 postoperative days and therefore should not be used as a sole antiplatelet agent early after coronary surgery.

Aged↗
PubMed2004

A versatile technique for aortic root replacement without pre-manufactured composite graft: a 12-year experience.

BACKGROUND AND AIM OF THE STUDY: Replacement of the aortic root is the treatment of choice for aneurysmal dilatation. Many modifications of the Bentall technique have been described, as have valve-sparing procedures. The study aim was to determine the outcome of a versatile modification of composite replacement that has been adopted over the past 12 years. Separate graft and prosthetic valve components were used to allow freedom of valve choice and the use of an appropriately sized graft for the distal aortic anastomosis. METHODS: Between January 1990 and March 2002, 59 patients (45 males, 14 females; mean age 56 +/- 14 years) underwent aortic root replacement using this technique. Indications for surgery were elective in 35 patients and emergent (usually type A aortic dissection) in 24. The range of valve prostheses used, their size, and the size of aortic graft used in each case was assessed. Durations of ischemia and cardiopulmonary bypass were recorded, as was postoperative blood loss and subsequent patient progress, including valve-related events, perioperative mortality and actuarial survival. RESULTS: A wide range of aortic graft sizes was combined with both mechanical and tissue valves (from 1-7 mm larger in diameter). Median postoperative blood loss was 550 ml (IQR 400-800 ml). Perioperative mortality was 5.1%. There were no valve- or technique-related deaths, and the median actuarial survival was 13.17 years. During a 12-year follow up there were no proximal aortic reoperations. CONCLUSIONS: This technique had favorable perioperative mortality, produced a secure proximal suture line, and allowed the surgeon free choice of both valve type and size of aortic graft. This minimized tension at the distal suture line, and produced good hemostasis, especially in those patients with fragile dissected tissues.

Adult↗
PubMed2003

Indirect comparison meta-analysis of aspirin therapy after coronary surgery.

OBJECTIVES: To evaluate the efficacy of low and medium dose aspirin therapy after coronary surgery by using an indirect comparison meta-analysis. DATA SOURCES: Systematic literature search of Medline, Embase, Cochrane controlled trials register, and trial register sites on the internet. STUDY SELECTION: Outcome was evaluated by angiography and reported as graft occlusion and rate of events in patients. Trials that did not include aspirin as the sole therapy or did not have a placebo control arm were excluded. Articles were assessed for eligibility and quality and grouped according to dosage. The estimated difference in effect of low and medium dose aspirin on graft occlusion was obtained by combining the estimated log relative risks of low dose with placebo and medium dose with placebo. RESULTS: For graft occlusion, the medium dose trials yielded a relative risk reduction of 45% compared with 26% for the low dose trials. The greater effect in the medium dose trials is summarised by a relative risk ratio of 0.74 (95% confidence interval 0.52 to 1.06; P = 0.10) for graft occlusion and 0.81 (0.57 to 1.16; P = 0.25) for events in patients. CONCLUSIONS: Medium dose aspirin may more successfully reduce graft occlusion than low dose regimens within the first year after coronary surgery.

Aspirin↗
PubMed2003

Midterm clinical and echocardiographic results with patch glue repair of left ventricular free wall rupture.

BACKGROUND: Left ventricular free wall rupture (LVFWR) is a dramatic complication after myocardial infarction. We present our mid-term clinical and echocardiographic results of LVFWR with an epicardial patch without cardiopulmonary bypass. METHODS: From February 1993 to May 2001, 17 patients underwent surgery for LVFWR. The mean age+/-SD of 12 males and 5 females was 68+/-10 years. All patients presented for emergency surgery with cardiac tamponade confirmed on echocardiography. After opening the chest and identification of the site of rupture, a Goretex patch was fashioned and applied with enbucrilate surgical glue. RESULTS: Effective control of bleeding was achieved in all cases. There were no on-table deaths. The operative (30 day) mortality was 23.5% (4/17). One death occurred because of patch failure, two because of cardiogenic shock, and one from pneumonia. On follow-up at a median of 2.2 years (interquartile range, 1.1 to 4.3 years), two further deaths occurred, one from myocardial infarction and another of undetermined etiology. Echocardiography did not reveal any evidence of restriction to left ventricular free wall motion. CONCLUSIONS: Patch glue repair is expedient, simple and effective; with no adverse effects on mid-term ventricular dynamics. In view of superior published results to infarctectomy and repair with extra corporeal circulation, it should be considered to be the initial procedure of choice for the surgical repair of LVFWR.

Aged↗
PubMed2003

Modified technique for mitral repair without ring annuloplasty.

Mitral valve repair is the procedure of choice to correct mitral regurgitation. Most operative techniques use an annuloplasty ring to provide stability and durability to the correction. We present a modification of existing repair techniques, without the use of an annuloplasty ring, in which plication sutures allow both annular remodeling and stability. Clinical and echocardiographic follow-up in our series of 60 patients with a mean follow-up of 29 months is presented.

Humans↗
PubMed2003

A method for descending thoracic aortic replacement retaining a posterior strip bearing intercostal vessels.

Operations for aneurysms of the descending thoracic aorta are still fraught with danger. Spinal cord injury remains a major cause of morbidity. Many therapeutic strategies have been suggested to reduce the incidence of this devastating complication, including reimplantation of intercostal vessels. However, reimplantation of intercostal vessels, both individually or in groups, is time consuming and compounded by the absence of a reliable means of identifying which vessels actually supply the cord. We present a technique that allowed inclusion of all potentially important descending aortic branching vessels into the repair leading to a favorable outcome in a series of patients.

Aorta, Thoracic↗
PubMed2003

A simple model to predict coronary disease in patients undergoing operation for mitral regurgitation.

BACKGROUND: Coexistent coronary disease can be identified in a third of patients with mitral valve disease. This study aims to evaluate candidate selection strategy using risk factor identification and logistic regression and to develop an additive model for the prediction of coexistent coronary disease. METHODS: The sample is a consecutive series of patients who had mitral repair from 1987 to 1999. Sensitivities and specificities were calculated for each risk factor. Variables for prediction of coronary disease were entered into a univariate analysis, and predictors were entered into a forward and backward stepwise multivariate logistic regression model to form a predictive score. An additive model was derived from transformation of the logistic model. Receiver operating characteristic curves were used to compare discrimination and precision quantified by the Hosmer-Lemeshow statistic. RESULTS: The American Heart Association and American College of Cardiology risk factor identification selection criteria for the 359 patients who had screening coronary angiography yielded 100% sensitivity and 1% specificity. Risk prediction with our logistic model produced a receiver operating characteristic curve area of 0.91 and Hosmer-Lemeshow score of 3.4 (p = 0.9). Similar discriminating ability for our patients was achieved by the Cleveland Clinic logistic model (receiver operator characteristic curve area of 0.79; Hosmer-Lemeshow score of 12; p = 0.1). Our five-item additive model produced receiver operating characteristic curve area of 0.91 and Hosmer-Lemeshow score of 3.81 (p = 0.80). CONCLUSIONS: Simple risk factor identification has excellent sensitivity but is limited by specificity. Logistic regression modeling is an accurate risk prediction method but is difficult to apply at the bedside. Simplicity and accuracy may be achieved by the logistic regression-derived simple additive model.

Aged↗
PubMed2003

Pyrexia after cardiac surgery: natural history and association with infection.

BACKGROUND: Pyrexia is common after major surgery, and infection is often an important consideration. To investigate the natural history and association with infection, we performed a prospective observational study. METHODS: From November 2000 to January 2001, we studied 219 patients undergoing cardiac surgery screening daily for wound, respiratory, urinary tract, and other infections. Pyrexia was defined as temperature above 37.5 degrees C. RESULTS: Of 219 patients, 7 intraoperative deaths occurred and 1 patient was excluded because of preoperative endocarditis, leaving 211. The mean age (SD) was 64 (10) years, consisting of 172 male patients (81.5%). The proportion pyrexial on days 1, 2, and 5 was 30.0%, 25.8%, and 10.3%, respectively. More patients undergoing urgent or emergency procedures (17.7% versus 7.8%; P =.03) subsequently developed pyrexia. However, there were no differences in wound infection (3.4% versus 8.3%; P =.13), positive cultures for respiratory (14.7% versus 11.4%; P =.16), urinary tract (5.2% versus 2.0%; P =.09), or other infection (8.6% versus 7.3%; P =.71) in patients experiencing postoperative pyrexia compared with those who did not. CONCLUSIONS: Pyrexia is common after cardiac surgery and resolves in the majority of patients by day 5. Because there is no association between early pyrexia and infection, diagnosis of early postoperative infection by pyrexia alone is insufficient and is better established by clinical assessment with microbiological evidence.

Cardiac Surgical Procedures↗