Evaluation of an acetated Ringer-based contrast material mixture for postmortem computed tomography angiography.

PURPOSE: The purpose of this study was to compare an established postmortem contrast medium mixture based on polyethylene glycol (PEG) to an isotonic crystalloid with acetated Ringer solution (AR) as the base, both mixed with water-soluble iodinated contrast medium for postmortem computed tomography angiography (PMCTA) with the aim to avoid alterations of the corpse during autopsy. MATERIALS AND METHODS: The study included 20 cadavers; 10 had PMCTA with AR and 10 with PEG. PMCTA images were analyzed with respect to image quality, vascular contrast patterns and artifacts. Autopsy was evaluated for visual, organ, vessel and haptic alterations. The Wilcoxon rank sum test was used to search for differences in image quality between the two groups. Statistical significance was set at P<0.05. RESULTS: AR provided excellent contrast within the right coronary artery (P<0.001) but a lack of contrast within the left coronary artery (P=0.008) whereas PEG showed the opposite. A better image quality was observed in the PEG group by comparison with the AR group for right common carotid artery (P=0.03), left common carotid artery (P=0.01) and left coronary artery (P=0.008). No differences were found for ascending aorta (P=0.65), aortic arch (P=0.09), right circle of Willis (P=0.17), left circle of Willis (P=0.08), inferior vena cava (P=0.07) and abdominal aorta (P=0.08). Severe extravasation occurred in all (10/10; 100%) cadavers in the AR group but in none (0/10; 0%) in the PEG group (P<0.001). At autopsy, visual alteration with lilac discoloration of the face was observed in 4/10 cadavers (40%) in the AR group and in 9/10 cadavers (90%) in the PEG group (P=0.057). Haptic alterations were observed in 3/10 cadavers (30%) in the AR group and 10/10 cadavers (100%) in the PEG group (P=0.003). CONCLUSION: AR results in contrast medium mixture extravasation in all cadavers, but PEG altered the autopsy more severely. Both carrier substances result in specific substance-related artifacts and dependent opacification of the coronary arteries, but PEG is recommended for PMCTA exclusively with regard to diagnostic imaging.

Quality improvement in cardiac critical care.

Our quality improvement program began in 2004 to improve cardiac surgery outcomes. Early tracheal extubation in the cardiovascular intensive unit was utilized as a multidisciplinary driver for the quality improvement program. Continuous improvement in the rate of early extubation to drive multidisciplinary quality improvement in cardiac critical care correlated with decreased mortality, morbidity, and improved operational efficiency. Supportive educational efforts included, but were not limited to, principles of change, trust, competing values, crew resource management, evidence based medicine, and quality improvement.

Can timing of tracheal extubation predict improved outcomes after cardiac surgery?

INTRODUCTION: Early tracheal extubation is a common goal after cardiac surgery. Our study aims to examine whether timing of tracheal extubation predicts improved postoperative outcomes and late survival after cardiac surgery. We also evaluated the optimal timing of extubation and its association with better postoperative outcomes. METHODS: Between 2002 and 2006, 1164 patients underwent early tracheal extubation (<6 hours after surgery) and 1571 had conventional extubation (>6 hours after surgery). Propensity score adjustment and multivariable logistic regression analysis were used to adjust for imbalances in the patients' preoperative characteristics. Receiver operating characteristic curves (ROC) were used to identify the best timing of extubation and improved postoperative outcomes. Cox regression analysis was used to identify whether early extubation is a risk factor for decreased late mortality. RESULTS: Results - Early extubation was associated with lower propensity score-adjusted rate of operative mortality (Odds Ratio =0.55, 95% Confidence Intervals =0.31-0.98, p=0.043). Extubation within 9 hours emerged as the best predictor of improved postoperative morbidity and mortality (sensitivity =85.5%, specificity =52.7%, accuracy =64.5%). Early extubation also predicted decreased late mortality (Hazard Ratio =0.45, 95% Confidence Intervals 0.31-0.67, p<0.001). CONCLUSIONS: Early extubation may predict improved outcomes after cardiac surgery. Extubation within 9 hours after surgery was the best predictor of uncomplicated recovery after cardiac surgery. Those patients intubated longer than 16 hours have a poorer postoperative prognosis. Early extubation predicts prolonged survival up to 16 months after surgery.

Prevention of atrial fibrillation after cardiac surgery: the significance of postoperative oral amiodarone.

STUDY OBJECTIVES: Atrial fibrillation (AF) is a common occurrence after cardiac surgery (10 to 53%) that contributes to increased length of stay and hospital cost. Recent evidence suggests that treatment with amiodarone may provide safe and effective prophylaxis against AF in many patients undergoing cardiac operations. This study sought to investigate whether oral amiodarone administered postoperatively would reduce the incidence of postoperative AF. DESIGN: Prospective nonrandomized cohort study. PATIENTS AND PARTICIPANTS: In this prospective study, 1,196 consecutive patients who underwent various open-heart procedures with cardiopulmonary bypass between July 1999 and February 2000 received oral amiodarone, 400 mg bid, from the transfer to the cardiovascular recovery room until the day of hospital discharge, or up to 7 days postoperatively. The incidence of AF in this group of patients was compared with a group of 1,246 patients who underwent cardiac surgery with cardiopulmonary bypass in the preceding 8-month period (November 1998 to June 1999) at the same institution without receiving amiodarone postoperatively. SETTING: Tertiary health-care center. MEASUREMENT AND RESULTS: AF developed in 294 patients (25%) in amiodarone-treated group and in 385 patients (31%) in the control group (p = 0.001). In multivariate logistic regression analysis, oral amiodarone treatment emerged as an independent predictor of lower risk of AF (odds ratio, 0.7; 95%; 95% confidence interval, 0.6 to 0.9; p = 0.002) and shorter hospital length of stay (odds ratio, 0.8; 95% confidence interval, 0.5 to 0.9; p = 0.006). CONCLUSIONS: Postoperative oral amiodarone treatment is a safe and effective regimen associated with a reduced incidence of new-onset AF and decreased length of hospital stay. Prospective randomized trials are needed to evaluate the benefits of amiodarone treatment relative to its side effect profiles.

Late outcome of reoperative coronary revascularization on the beating heart.

BACKGROUND: Reoperative (redo) coronary artery bypass grafting (CABG) is associated with a higher morbidity and mortality than first-time CABG. An off-cardiopulmonary bypass (off-pump) approach to redo CABG, however, may potentially benefit redo patients. The aim of the present report is to describe the early and long-term clinical outcome of patients who underwent off-pump redo CABG between July 1985 and January 1999 in our institution. METHODS: Redo patients (n = 138) represented 13% of patients who had off-pump CABG during the period of study (n = 1072). Mean patient age was 63 +/- 12 years, and 67% were men. Surgical approaches included median sternotomy (n = 93, 67%), anterior (n = 20, 15%) and lateral (n = 25, 18%) minimally invasive direct coronary artery bypass (MIDCAB). RESULTS: Operative mortality was 2% (n = 3). Target lesion re-intervention was 6% (n = 9) Actuarial survival at a mean period of follow-up of 2.5 +/- 1 year (range: 1 month to 11 years) was 83%. Event-free survival (freedom from death, myocardial infarction, and repeat intervention) was 67%. Overall cardiac-related mortality was 10% (n = 14). CONCLUSION: Off-pump redo CABG can be safely performed with a relatively low mortality rate and a low rate of target lesion revascularization.

Stroke after coronary artery bypass: incidence, predictors, and clinical outcome.

BACKGROUND AND PURPOSE: Early postoperative stroke is a serious adverse event after coronary artery bypass grafting (CABG). This study sought to investigate risk factors, prevalence, and prognostic implications of postoperative stroke in patients undergoing CABG. METHODS: We investigated the predictors of postoperative stroke (n=333, 2%) in 16 528 consecutive patients who underwent CABG between September 1989 and June 1999 in our institution. Predictors of postoperative stroke were identified by logistic regression analysis. RESULTS: Among the preoperative and postoperative factors, significant correlates of stroke included (1) chronic renal insufficiency (P<0.001), (2) recent myocardial infarction (P=0.01), (3) previous cerebrovascular accident (P<0.001), (4) carotid artery disease (P<0.001), (5) hypertension (P<0.001), (6) diabetes (P=0.001), (7) age >75 years (P=0.008), (8) moderate/severe left ventricular dysfunction (P=0.01), (9) low cardiac output syndrome (P<0.001), and (10) atrial fibrillation (P<0.001). Postoperative stroke was associated with longer postoperative stay (11+/-4 versus 7+/-3 days for patients without stroke, P<0.001) and with higher in-hospital mortality (14% versus 2.7% for patients without stroke; P<0.001). CONCLUSIONS: Stroke after CABG is associated with high short-term morbidity and mortality. Increased stroke risk can be predicted by preoperative and postoperative clinical factors.

Carcinoma arising in an amputation stump.

We describe a 62-year-old diabetic man who presented with squamous cell carcinoma on his right thigh amputation stump 52 years after the procedure. The potential relationship of the chronic irritation by the artificial leg and the malignant transformation of the healing scar as well as optimal treatment options of scar-tissue carcinomas are reviewed.

Coronary revascularization without cardiopulmonary bypass in high-risk patients: a route to the future.

Previous reports have demonstrated that reoperative coronary revascularization, advanced age, female sex, and impaired left ventricular dysfunction are independent predictors of operative mortality after coronary artery bypass grafting (CABG). CABG without cardiopulmonary bypass (off-pump CABG) has been proposed as a potential therapeutic alternative in these high-risk patient groups. Despite the substantial learning curve associated with off-pump CABG, early outcomes of off-pump CABG in high-risk patients are better than those associated with the conventional on-pump CABG approach. These results suggest that off-pump CABG is a safe alternative to on-pump CABG in high-risk patients. Randomized prospective studies are needed to validate the results of these initial retrospective reports and to demonstrate the long-term benefits of this approach.

Minimally invasive coronary revascularization in women: A safe approach for a high-risk group.

PURPOSE: Female gender has been shown to be an independent risk factor for mortality in coronary artery bypass graft (CABG) surgery. This report analyzes our early outcomes in 304 women who underwent off-pump coronary artery bypass (OPCAB) surgery at the Washington Hospital Center (Washington, DC) over the last 3 years to determine whether this is a safe approach for coronary bypass in women. METHODS: A retrospective review of 5528 cases of CABG bypass (on-pump) and 840 cases of OPCAB surgery, from June 1996 to July 1999, was performed. Women accounted for 1527 (27.6%) of the on-pump bypass cases and 304 (36.2%) of the OPCABs. All cases without cardiopulmonary bypass were included, with the majority of the most recent cases being multivessel revascularization. The data for analysis were obtained from our cardiac surgery database and included cases from all surgeons operating at the Washington Hospital Center, although the majority of off-pump cases were performed by only a few of these surgeons. RESULTS: The two groups were similar with respect to urgent cases, redos, and other comorbities including preoperative congestive heart failure, peripheral vascular disease, transient ischemic attack (TIA), cerebral vascular accident, and previous myocardial infarction. The mean age for the two groups was similar, 67 years for the off-pump group and 66 years for the on-pump group. The absolute number of all off-pump cases increased each year (from 175 to a total of 373), representing a corresponding increase in percentage of all coronary artery bypass procedures (from 9% to 16%). Of the total number of patients undergoing CABG, the percentage of women who underwent OPCAB doubled from 3% to 6% over the time period analyzed. The percentage of single-vessel cases in the off-pump group fell from 88% to 41% as multivessel bypasses became more routine However, the percentage of patients aged > 75 years was greater for the off-pump group (30%) than for the on-pump group (24%). Otherwise, the two groups differed only in diabetic disease (36% off-pump compared with 46% on-pump; p = 0.001) and previous transcatheter therapy (38% off-pump compared with 29% on-pump; p = 0.003). Patients who had OPCABs received fewer postoperative transfusions (40%) than the on-pump group (59%; p < 0.001). The off-pump group also had fewer neurological complications in the form of TIAs or strokes (0.3%) compared with the on-pump group (3.5%; p = 0.001). The mortality rate was 2.3% off -pump versus 4.1% on pump but did not reach statistical significance in this study (p =.12). CONCLUSION: Myocardial revascularization in women can be performed safely without cardiopulmonary bypass. In our series, the mortality for women receiving off-pump revascularization was lower than the on-pump cohorts despite an older age and higher incidence of diabetes. Although the absolute mortality rates did not reach statistical significance, we were encouraged that the mortality rate for women operated on without CPB dropped to the mortality rate typically seen in men. We also observed a favorable tendency in the off-pump group for a shorter length of stay and a lower incidences of transient ischemic attacks, strokes, post-op bleeding, and blood transfusions. A larger series of patients with multivariate analysis and/or a prospective trial will need to be analyzed in order to confirm our findings.

Coronary revascularization of the circumflex system: different approaches and long-term outcome.

BACKGROUND: Minimally invasive direct coronary artery bypass, without cardiopulmonary bypass, through a left lateral thoracotomy approach (lateral MIDCAB), is a safe alternative to coronary artery bypass surgery using cardiopulmonary bypass (on-pump CABG) of the circumflex system via median sternotomy. However, it is unknown whether lateral MIDCAB may yield an improved long-term outcome over the conventional on-pump median sternotomy approach. METHODS: We compared the perioperative outcomes of patients undergoing lateral MIDCAB (n = 34) versus conventional on-pump CABG of the circumflex system (n = 16) from June 1996 to July 1999. The two groups were similar with respect to baseline characteristics and risk stratification. Patients who required only one or two grafts for complete revascularization were included. RESULTS: Lateral MIDCAB patients had a lower need than on-pump CABG patients for intraoperative (12% MIDCAB vs 43% on-pump CABG, p = 0.03) and postoperative transfusions (29% vs 69%, p = 0.01), had fewer neuropsychologic changes (0% vs 19%, p = 0.03), and had a lower rate of postoperative atrial fibrillation (12% vs 44%, p = 0.02). Lateral MIDCAB was also associated with a significantly lower postoperative length of stay (5 +/- 2 vs 7 +/- 3 days, p = 0.02). Actuarial survival at a mean period of follow-up of 19 +/- 11 months was 97% for the lateral MIDCAB versus 88% for the on-pump CABG group (p = 0.6). Event-free survival was 88% for lateral MIDCAB versus 81% for on-pump CABG (p = 0.1). CONCLUSIONS: Lateral MIDCAB may safely be performed in patients with isolated coronary artery disease of the circumflex system with improved early morbidity and an abbreviated hospital stay compared with conventional median sternotomy on-pump CABG.

Complete myocardial revascularization on the beating heart with epicardial stabilization: anesthetic considerations.

OBJECTIVE: To describe an anesthetic management protocol for patients undergoing cardiac surgery with multiple coronary artery bypass grafts without cardiopulmonary bypass (off-pump CABG surgery) by median sternotomy with mechanical stabilization. DESIGN: Retrospective nonrandomized analysis. SETTING: Tertiary care hospital. PARTICIPANTS: Sixty-six consecutive patients on whom off-pump CABG surgery by median sternotomy was attempted. INTERVENTIONS: Anesthesia was induced with a combination of etomidate and fentanyl; pancuronium bromide was given for muscle relaxation; and anesthesia was maintained with isoflurane, desflurane, or sevoflurane in 100% oxygen. Maintenance of normothermia was attempted by keeping the room temperature at 70 degrees F, warming all fluids to 41 degrees C, and using 2.5 L/min of fresh gas flows and a heat and humidity exchanger. When available, a convective forced-air blanket was used to cover patients' head and shoulders. Patients who were not slated for revascularization of the circumflex vessels and who had good ventricular function received central venous pressure monitoring (26%); all other patients received a pulmonary artery catheter. MEASUREMENTS AND MAIN RESULTS: Of the 66 patients, 36% required an epinephrine infusion at a mean rate of 1.45+/-2.05 microg/min intraoperatively to maintain hemodynamic stability; 25% required inotropic support for < 12 hours in the intensive care unit. CONCLUSION: Institution of systematic hemodynamic management was associated with the successful completion of the surgical procedure in 61 patients (92%). Only 5 patients required conversion to regular CABG surgery with cardiopulmonary bypass.

Beating heart versus conventional single-vessel reoperative coronary artery bypass.

BACKGROUND: Reoperative (redo) coronary artery bypass grafting (CABG) with cardiopulmonary bypass (on-pump) is associated with a higher morbidity and mortality than first-time CABG. It is unknown, however, whether CABG without cardiopulmonary bypass (off-pump) may yield an improved clinical outcome over conventional on-pump redo CABG. METHODS: We compared the perioperative outcomes of patients with single-vessel disease who underwent on-pump (n = 41) versus off-pump (n = 91) redo CABG between April 1992 and July 1999. The two groups were similar with respect to baseline characteristics and risk stratification: mean Parsonnet scores were 26 +/- 9 for on-pump versus 24 +/- 8 for off-pump patients (p = nonsignificant). RESULTS: On-pump redo patients had a higher rate of postoperative transfusions (58% on-pump versus 27% off-pump, p = 0.001), prolonged ventilatory support (17% on-pump versus 4% off-pump, p = 0.03), and a higher rate of postoperative atrial fibrillation (29% on-pump versus 14% off-pump, p = 0.04). On-pump redo CABG was also associated with prolonged postoperative length of stay (8 +/- 4 days on-pump versus 5 +/- 2 days off-pump, p < 0.001). In-hospital mortality was significantly higher in on-pump than in off-pump patients (10% versus 1%, p = 0.03). CONCLUSIONS: Single-vessel off-pump redo CABG can be performed safely with a lower operative morbidity and mortality than on-pump CABG and an abbreviated hospital stay compared with conventional on-pump redo CABG.

Atrial fibrillation after beating heart surgery.

Postoperative atrial fibrillation (AF) is a frequent adverse event after coronary artery bypass grafting (CABG) and may negatively affect the early clinical outcome. We sought to investigate the risk factors, prevalence, and prognostic implications of postoperative AF in patients submitted to CABG without cardiopulmonary bypass (off-pump). The study population comprised 969 patients, 645 men (67%) and 324 women (33%) who had off-pump CABG at the Washington Hospital Center from January 1987 to May 1999. Preoperative AF patients were excluded (n = 15). Two hundred six patients (age 69 +/- 10 years, 137 men [66%]) developed AF, whereas 763 patients (age 61 +/- 12 years, 508 men [67%]) did not. Predictors of AF included age >75 years (odds ratio [OR] 3.0, 95% confidence interval [CI] 1.9 to 4.5; p <0.001), history of stroke (OR 2.1, CI 1.2 to 3.7; p = 0. 007), postoperative pleural effusion requiring thoracentesis (OR 3.2, CI 1.0 to 9.4; p = 0.03), and postoperative pulmonary edema (OR 5.1, CI 1.2 to 21; p = 0.02). Minimally invasive direct CABG was associated with a lower incidence of AF (OR 0.4, CI 0.3 to 0.7; p <0. 001). AF was associated with a prolonged postoperative hospital stay (9 +/- 6 days AF vs 6 +/- 5 days no AF, p <0.001). In-hospital mortality was significantly higher in AF patients (3% AF vs 1% no AF, p = 0.009). Patients with persistent AF had a higher postoperative in-hospital stroke rate than patients without persistent AF (9% vs 0. 6%, p <0.001). AF after beating heart surgery is associated with a higher in-hospital morbidity, mortality, and prolonged hospital stay. A minimally invasive surgical approach (minimally invasive direct CABG) is associated with a lower risk of AF.

Beating heart surgery in octogenarians: perioperative outcome and comparison with younger age groups.

BACKGROUND: Octogenarians have higher morbidity and mortality rates (9% to 16%) after coronary artery bypass grafting with cardiopulmonary bypass, compared with younger patients. METHODS: We compared the perioperative outcome and hospital stay after coronary artery bypass grafting without cardiopulmonary bypass (off-pump) from January 1987 to May 1999, among patients older than 80 years (n = 71), patients between 70 and 79 years (n = 228), and patients whose age ranged from 60 to 69 years (n = 296). In comparison with younger patients, more octogenarians were female (51% versus 39% in patients aged 70 to 79 years and 35% in those aged 60 to 69 years, p = 0.04), they had previous myocardial infarction more frequently (48% versus 47% versus 34%, respectively, p = 0.008), and were operated on urgently (69% versus 56% versus 52%, respectively, p = 0.04). RESULTS: Postoperative complications that were significantly higher in octogenarians compared with younger groups included pneumonia (6% in octogenarians versus 2% in patients aged 70 to 79 years and 0% in patients aged 60 to 69 years, p = 0.001) and atrial fibrillation (47% versus 32% versus 21%, respectively, p<0.001). By multivariate logistic regression analysis, age over 80 years was an independent predictor of prolonged hospital stay (odds ratio = 2.7, 95% confidence interval, 1.4 to 5, p<0.001). The in-hospital mortality rate was higher in octogenarians (6% versus 3% for 70 to 79 year-olds and 0.3% for 60 to 69 year-olds, p = 0.006). CONCLUSIONS: When appropriately applied in patients older than 80 years, off-pump coronary artery bypass grafting can be done with acceptable postoperative morbidity, mortality, and hospital stay.

One-year clinical outcome after minimally invasive direct coronary artery bypass.

BACKGROUND: Minimally invasive coronary artery bypass (MIDCAB) is a new surgical technique by which the left internal mammary artery is anastomosed under direct visualization to the left anterior descending artery without cardiopulmonary bypass. METHODS AND RESULTS: We followed all 274 patients who underwent MIDCAB from the time it was introduced at a single center. In-hospital and 1-year clinical events were source-documented and adjudicated. The in-hospital major acute cardiac event rate was 2.2%; this included a 1.1% mortality rate. At 1 year, the respective rates were 7.8% and 2. 5%. When compared with the initial 100 procedures, the subsequent 174 procedures had shorter vessel occlusion times (10+/-5 versus 14+/-6 minutes; P:=0.009), times to extubation (6+/-3 versus 14+/-10 hours; P:<0.001), and lengths of hospital stay (2.1+/-1.9 versus 3. 2+/-3.1 days; P:=0.04). Cumulative 1-year adverse cardiac events were 11% in the initial 100 cases and 6% in the subsequent 174 cases (P:=0.17). CONCLUSIONS: Excellent clinical results can be achieved with the MIDCAB technique. The clinical adverse event rate may decrease with accumulated experience.

A xiphoid approach for minimally invasive coronary artery bypass surgery.

BACKGROUND: The premise for adopting minimally invasive cardiac surgery techniques for myocardial revascularization is to reduce the patient's morbidity without compromising the efficacy of conventional coronary artery bypass. However, opening the pleura has been a limitation of using these approaches. AIM: We used the xiphoid approach as an alternative to opening the pleura and to minimize pain after minimally invasive coronary artery bypass surgery. METHODS: We review our surgical experience in 55 patients who underwent minimally invasive direct coronary artery bypass (MIDCAB) surgery through a xiphoid approach between October 1997 and August 1999. Thoracoscopy (n = 31) or direct vision (n = 24) were used for internal mammary artery (IMA) harvesting. Mean patient age was 67 +/- 10 years and 65% were men. The mean Parsonnet score was 23 +/- 10. Performed anastomoses included left IMA (LIMA) to the left anterior descending (LAD) artery (n = 53), LIMA-to-LAD and saphenous vein graft from the LIMA to the right coronary artery (n = 1), and LIMA-to-LAD and right IMA (RIMA) to right coronary artery (n = 1). RESULTS: Postoperative complications included atrial fibrillation (12%), acute noninfectious pericarditis (12%), and acute renal failure (5%). Mean postoperative length of stay was 4 +/- 2 days. Angiography was performed in 16 patients and demonstrated excellent patency of the anastomoses. There was no operative mortality. Actuarial survival was 98% in a mean follow-up period of 11 +/- 5 months. CONCLUSIONS: Minimally invasive coronary artery bypass can be performed safely through a xiphoid approach with low morbidity, mortality, and a relatively short hospital stay.

Wound infections after minor limb lacerations: risk factors and the role of antimicrobial agents.

BACKGROUND: The requirement for antimicrobial agents in patients with minor limb lacerations was prospectively studied. METHODS: The development of wound infections in patients with minor limb lacerations who received amoxicillin plus clavulanate acid treatment (group A, 52 patients) was studied and compared with patients who did not (group B, 48 patients). RESULTS: Wound infection occurred in 6 (11.5%) and 10 (21%) patients in groups A and B, respectively (p>0.10). Statistically significant risk factors for the development of infection were diabetes mellitus (odds ratio [OR], 15.8; p<0.001), lower limb lacerations (OR, 33.5; p<0.001), lacerations caused by compressive forces (OR, 21.6; p = 0.007), laceration length from 5 to 8 cm (OR, 7.04; p = 0.001), ragged laceration edge (OR, 2.55; p = 0.049), and skin tension (OR, 2.00; p = 0.006). CONCLUSION: The use of antimicrobial agents in minor limb injuries was not associated with a significant reduction of infection rate. Routine antimicrobial treatment is discouraged.

Hickman-Broviac catheter-related infections in children with malignancies.

Infectious complications are frequently encountered following Hickman-Broviac (H-B) catheter insertion. The medical records of 164 children with malignancies who underwent H-B catheter insertion from March 1, 1988 to December 31, 1997 were reviewed retrospectively. During a 35,697 catheter-day period, 77 catheter-related infections occurred, including 50 catheter-insertion-site infections and 27 bloodstream infections. The risk for the development of catheter-related infections was 2.15 per 1000 catheter-days (1.4 and 0.75 per 1000 catheter-days for catheter-insertion-site and bloodstream infections, respectively). In 17 (63%) of 27 episodes of bloodstream infections, antimicrobial treatment controlled the infection without catheter removal. A previous catheter-insertion-site infection caused by Staphylococcus epidermidis (p=0.01), the occurrence of mechanical catheter complications (p=0.007), and a normal coagulation status of the host (p=0.03) were significantly associated with the development of catheter-related bloodstream infections. H-B catheters remain important in pediatric oncology. Due to the significant morbidity associated with the development of catheter-related bloodstream infections, risk factors found to increase the incidence rate of such infections must be identified and properly managed.

Intraindividual comparison of diltiazem and verapamil on induction of paroxysmal supraventricular tachycardia.

The effects of i.v. diltiazem (0.25 mg/kg) and i.v. verapamil (0.15 mg/kg) were studied in 18 patients with recurrent paroxysmal supraventricular tachycardia (SVT) who underwent serial electrophysiological studies. In 10 of 18 patients with extranodal accessory pathways the effects of diltiazem and verapamil were similar in comparable plasma concentrations. SVT was prevented in 10/10 cases after diltiazem and 9/10 cases after verapamil, furthermore there as an increase in antegrade refractoriness of the normal AV nodal pathway of 22 and 27%, respectively; accessory pathway refractoriness and conduction remained unchanged in both drugs. In 8 of 18 patients with dual AV nodal pathways diltiazem was significantly less effective as compared to verapamil (p < 0.02) regarding prevention ov SVT (3/8 vs. 8/8 cases) and increase in the antegrade refractoriness of the slow AV nodal pathway (+21 vs. +34%). However, both drugs produced equivalent slowing of antegrade AV nodal conduction and a similar increase in antegrade refractoriness of the fast AV nodal pathway. In all 18 patients, the site of action of both drugs was the antegrade limb, regardless of SVT mechanism. The data suggest that the two calcium antagonists are equipotent in AV reentrance but verapamil may offer greater benefit in AV nodal reentrance than diltiazem.