Early hormonal therapy stabilizes hemodynamics during donor procurement.

BACKGROUND: Hemodynamic instability has been implicated in the loss of otherwise transplantable organs. We examined the hypothesis that administration of hormonal therapy early during donor management would stabilize hemodynamics and increase the number of organs procured. METHODS: We retrospectively analyzed 133 consecutive donor records from a single organ procurement organization. Controls (C) received no early hormonal therapy. A steroid group (S) received methylprednisolone only and a combination hormonal therapy group (CH) received thyroxine, methylprednisolone, dextrose, and insulin at the start of donor management (t(0h)). Adrenergic support was adjusted to maintain mean arterial blood pressure (MAP) at > or =60 mm Hg. Doses of adrenergic agents were assessed at t(0h), 4 hours (t(4h)), and just prior to procurement (t(proc)). RESULTS: Baseline characteristics were similar in all groups. Dosages of adrenergic agents decreased over time in all groups. A significant decrease in adrenergic requirements was seen in the CH group compared with the C group at t(4h) and t(proc). A trend toward decreased adrenergic requirements was noted in S compared with C at t(4h) and t(proc). Slightly more total organs were procured from S and CH compared with C. CONCLUSIONS: Significantly less adrenergic support was required with early use of CH. A similar (although nonsignificant) reduction was seen with S. The benefit(s) of CH vs corticosteroids alone remains uncertain and requires further study.

The incremental value of internet-based instruction as an adjunct to classroom instruction: a prospective randomized study.

PURPOSE: Computer-based methods of instruction offer the possibility of helping medical students to learn clinical skills and professionalism. Without rigorous documentation of its pedagogic advantages, the utility of Internet-based teaching is not solidly grounded. The authors carried out a prospective, randomized study of educational outcomes, comparing a traditional classroom course in clinical ethics with the same course supplemented by Internet-based discussion. METHODS: Introduction to Clinical Ethics is a sophomore medical school course that teaches a specific method for analyzing clinical ethical problems. One sophomore class was randomly assigned to either classroom teaching alone (traditional group; n = 65) or classroom teaching supplemented with Internet-based discussions of cases illustrating ethical issues (Internet component group; n = 62). A final case analysis comprehensively evaluated students' understanding of the analytic method taught in the course. Grades for both groups on the final case analyses, which were rated by two external reviewers, were compared. RESULTS: The students' understanding of ethical analysis, as measured by grades of external reviewers on the final paper, was significantly higher for those in the course with the Internet component than it was for those in the traditional course (3.0 +/- 0.6 and 2.6 +/- 0.7, respectively; p <.005). CONCLUSION: The study documents the incremental value of Internet-based teaching of clinical ethics to sophomore medical students.

Congenital Heart Surgery Nomenclature and Database Project: palliation, correction, or repair?

BACKGROUND: Inconsistent use of the terms palliation, repair, and correction, fosters unclear thinking about the goals of cardiac operation. Actual usage of these terms has not been previously documented. METHODS: Every article, for two years, pertaining to congenital heart disease in The Annals of Thoracic Surgery and The Journal of Thoracic and Cardiovascular Surgery was systematically inspected for terms of classification. RESULTS: In the 301 articles reviewed, repair and correction were used virtually interchangeably. Palliation was generally used distinctively, but all 3 descriptors were used for 3 operations. The etymology of each descriptive term suggests that they have distinct traditional definitions and connotations. Repair suggests returning to normal that which was once normal, while correction carries no implication of prior normalcy; thus, correction is the more etymologically correct term for congenital heart operations. In current literature, palliation is used improperly for a few operations to denote lack of anatomic correction or lack of permanence of correction. CONCLUSIONS: Because proper usage reflects both etymology and actual usage, we suggest that repair and correction may be used interchangeably. Palliation, however, should describe only operations that are not intended to provide normal cardiac physiology.

Ethics gap in surgery.

BACKGROUND: Discussion of ethical issues occurs much less often in the surgical than in the medical literature. The reasons for this "ethics gap" are unknown. METHODS: Our clinical faculty ranked the ethical and legal acceptability of four treatment options in two cases of surrogate decision making. Only one option in each case was ethically and legally unacceptable (treating despite objection by the surrogate decision maker). RESULTS: Surprisingly often, faculty mistakenly believed the ethically unacceptable option to be acceptable, and the legally unacceptable option to be acceptable. Surgeons were not ethically different from other physicians. Surgeons (19 of 31, 62%), however, were significantly (p < 0.05) more likely than internists (18 of 51, 35%) or pediatricians (4 of 18, 22%) to believe, mistakenly, that operating on the baby without parental consent was legally acceptable. CONCLUSIONS: This pilot study did not identify why the surgical literature contains a relative dearth of ethics discussion. Broader investigations are needed, because it is important that we understand the reasons for the gap. Surgeons' strong ethic of personal responsibility for patients' welfare should be transmitted to young trainees, a goal best achieved by discussing and writing about ethics. Moreover, our legal data suggest that a gap may also exist between surgeons and other physicians in understanding health law.

Magnesium supplementation in the prevention of arrhythmias in pediatric patients undergoing surgery for congenital heart defects.

BACKGROUND: The efficacy of magnesium in the prevention of arrhythmias in pediatric patients after heart surgery remains unknown. Therefore we prospectively examined the effect of magnesium treatment on the incidence of postoperative arrhythmias in pediatric patients undergoing surgical repair of congenital heart defects. METHODS AND RESULTS: Twenty-eight pediatric patients undergoing heart surgery with cardiopulmonary bypass were prospectively, randomly assigned in a double-blind fashion to receive intravenous magnesium (magnesium group, n = 13; 30 mg/kg) or saline (placebo group, n = 15) immediately after cessation of cardiopulmonary bypass. Magnesium, potassium, and calcium levels were measured at defined intervals during surgery and 24 hours after surgery. Continuous electrocardiographic documentation by Holter monitor was performed for 24 hours after surgery. Magnesium levels were significantly decreased below the normal reference range for patients in the placebo group compared with the magnesium group on arrival in the intensive care unit and for 20 hours after surgery. Magnesium levels remained in the normal range for patients in the magnesium group after magnesium supplementation. In 4 patients in the placebo group (27%), junctional ectopic tachycardia developed within the initial 20 hours in the intensive care unit. No junctional ectopic tachycardia was observed in the magnesium group (P =.026). CONCLUSIONS: Although this study was originally targeted to include 100 patients, the protocol was terminated because of the unacceptable incidence of hemodynamically significant junctional ectopic tachycardia that was present in the placebo group. Thus low magnesium levels in pediatric patients undergoing heart surgery are associated with an increased incidence of junctional ectopic tachycardia in the immediate postoperative period.

Long-term experience with the St. Jude Medical valve prosthesis.

BACKGROUND: All patients undergoing St. Jude Medical valve replacement at the Medical University of South Carolina since January 1979 have been followed prospectively at 12-month intervals. METHODS: This report describes long-term experience in 710 adult patients undergoing isolated aortic (AVR) (418) or mitral valve replacements (MVR) (292) with this prosthesis from January 1979 to December 1996. RESULTS: Ages ranged from 19 to 84 years (54.8 +/- 15.1 AVR, 51.8 +/- 12.9 MVR; mean +/- SD). Male gender predominated in the AVR group (70%) and female gender in the MVR group (62%). One hundred and fifty-seven patients (22%) had associated coronary artery bypass grafting (AVR 27%, MVR 15%). Thirty-day operative mortality was 5.3% (22/418) in the AVR group and 5.1% (15/292) in the MVR group. Follow-up is 96.9% complete and ranges from 1 month to 16.9 years (AVR, 2,376 patient-years, mean 5.7 +/- 4.5 years; MVR, 1,868 patient-years, mean 6.4 +/- 4.8 years). In the AVR group, 120 late deaths have occurred and actuarial survival was 78.0 +/- 2.3%, 58.0 +/- 3.2%, and 36.8 +/- 4.8%; at 5, 10, and 15 years, respectively. Forty-six patients have sustained 55 thromboembolic (TE) events (2.3%/patient-year). Fifty-one patients had anticoagulant-related bleeding complications (2.7%/patient-year). The mean improvement in New York Heart Association (NYHA) functional class from preoperative to postoperative was 3.0 +/- 0.8 to 1.7 +/- 0.1 (p < 0.05). In the MVR group, there have been 84 late deaths, and the actuarial survival was 79.3 +/- 2.5%, 60.1 +/- 3.5%, and 49.3 +/- 4.1% at 5, 10, and 15 years, respectively. Fifty-two patients have had 64 TE events (3.5%/patient-year). Twenty-three patients had anticoagulant-related bleeding complications (1.6%/patient-year). The mean improvement in NYHA functional class was from 3.3 +/- 0.6 to 1.8 +/- 0.1. There were no mechanical failures in either group. CONCLUSIONS: With a follow-up now extending to 17 years, the St. Jude Medical valve continues to be a reliable mechanical prosthesis with low and stable rates of valve-related complications.

Esmolol for the management of pediatric hypertension after cardiac operations.

OBJECTIVE: Hypertension frequently occurs during the immediate postoperative period in children after repair of aortic coarctation but may also occur after repair of other congenital heart defects. Nitroprusside has often been used to control blood pressure in this setting. Because hypertension after coarctation repair is frequently associated with elevations in catecholamines, esmolol, a short-acting beta-blocking agent, may be an effective alternative. Therefore we undertook the first systematic investigation to determine the efficacy and disposition of esmolol in pediatric patients with acute hypertension after cardiac operations. METHODS: Twenty patients aged 1 month to 12 years (median 25.6 months) with acute hypertension after cardiac operations received esmolol in an opened-labeled trial. Esmolol was titrated to a blood pressure less than or equal to the 90th percentile for age. RESULTS: Ten patients had coarctation repair and the remaining patients underwent repair of other congenital heart defects. On final esmolol dose (mean +/- standard deviation dosage 700 +/- 232 microg/kg/min) there was a significant percent decrease in heart rate and systolic and diastolic blood pressures from postoperative values. Esmolol dose was significantly associated with percent reduction in systolic blood pressure. Final esmolol dose and total body clearance were significantly higher in patients after coarctation repair. There were significant associations between esmolol dose and esmolol blood concentrations at steady state. CONCLUSIONS: The dosage required to control hypertension in patients after repair of aortic coarctation was higher than patients who underwent repair of other congenital heart defects. Esmolol was effective in controlling blood pressure in 19 of 20 patients without adverse effects.

Neurologic outcomes in children with post-pump choreoathetosis.

Eleven children who had post-pump choreoathetosis develop after cardiopulmonary bypass were evaluated in their perioperative course to determine factors that may correlate with their neurologic outcome. Results showed that preoperative cyanosis is associated with the development of a basal ganglia lesion. An acquired basal ganglia lesion and preoperative cyanosis are associated with persistence of post-pump choreoathetosis. The combination of cyanotic heart disease and a scan-identified basal ganglia lesion indicates a poor prognosis for the patient with persistent post-pump choreoathetosis. Also, the presence of total circulatory arrest is associated with a decrease in developmental quotient but not the persistence of post-pump choreoathetosis.

Anticoagulation in children with mechanical valve prostheses.

BACKGROUND: Clotting complications in patients with mechanical valve prostheses can be prevented with either warfarin sodium (Coumadin; DuPont, Wilmington, DE) or antiplatelet agents. In children, it is not known whether one treatment regimen is more effective or safe than the other. METHODS: We prospectively followed up 64 children and young adults (aged 18 years or younger at implantation) with a mechanical valve on the left side of the heart, from October 1986 through October 1996. Forty-eight patients were treated with Coumadin and 16 with aspirin and dipyridamole. The two groups were similar in age, sex, valve location and size, mean length of follow-up, and operative indication. There has been a total follow-up of 272 patient-years on Coumadin and 116 patient-years on aspirin and dipyridamole. RESULTS: There was no difference between the two groups in survival or freedom from thromboembolism. Bleeding occurred more often in the patients taking Coumadin, but this difference was not statistically significant. Analysis of the literature showed thromboembolism and bleeding rates to be similar in the patients receiving Coumadin and those receiving antiplatelet agents. CONCLUSIONS: Coumadin and the combination of aspirin plus dipyridamole provided similar protection against complications in this group of children and young adults with left-sided St. Jude (St. Paul, MN) mechanical valves. The choice between the two regimens may depend on other factors, such as patient preference and convenience.