Comparison of transtracheal and extravascular Doppler determinations of stroke volume and cardiac output at various states of volume loading in piglets.

OBJECTIVE: To assess the applicability of a new technology in neonates. Transtracheal Doppler and extravascular Doppler determinations of stroke volume and cardiac output were compared with thermodilution measurements at various states of volume loading in an animal model. DESIGN: Prospective, descriptive study. SETTING: Animal research laboratory at a university medical center. SUBJECTS: Fourteen newly weaned piglets, weighing 2.8 to 6.5 kg. INTERVENTIONS: Doppler probes were placed on the endotracheal tube tip (transtracheal Doppler) and directly on the aortic adventitia (extravascular Doppler). A 4-Fr thermodilution catheter was inserted in the pulmonary artery. Stroke volume and cardiac output determinations were recorded at baseline, after a 15-mL/kg volume load and after successive 15-mL/kg blood withdrawals to exsanguination or a systolic blood pressure of < 20 mm Hg. MEASUREMENTS AND MAIN RESULTS: Transtracheal and extravascular Doppler measurements of cardiac output were not significantly different from thermodilution at any physiologic state. These techniques were able to measure stroke volumes and cardiac outputs at the low levels seen in severe hemorrhagic shock. CONCLUSIONS: Transtracheal Doppler and extravascular Doppler measurements of cardiac output compare favorably with thermodilution. These methods effectively followed trends from alterations in intravascular volume, even at very high heart rates and small stroke volumes. Transtracheal Doppler and extravascular Doppler should yield useful information in critically ill neonatal patients, where data regarding stroke volume and cardiac output may be useful in clinical management.

1988: use of a Bayesian statistical model for risk assessment in coronary artery surgery. Updated in 1995.

A computerized statistical model based on the theorem of Bayes was developed to predict mortality after coronary artery bypass grafting. From January, 1984, to April, 1987, at our hospital, 700 patients underwent isolated coronary artery bypass grafting. The presence or absence of 20 risk factors was determined for each patient. The first 300 patients formed the initial database of the Bayesian predictive model, and the remaining 400 patients were prospectively evaluated in four groups of 100 each. Each group was prospectively evaluated and then incorporated into the database to update the model. There was good agreement between predicted and observed results. Bayesian theory is particularly suited to this task because it (1) accommodates multiple risk factors, (2) is tailored to one's specific practice, (3) determines individual, rather than group, prognosis, and (4) can be updated with time to compensate for a changing patient population. These flexible attributes are especially valuable in light of recent changes in the coronary artery bypass graft patient profile.

Transtracheal Doppler in infants and small children following surgery for congenital heart disease: rational use of an improved technology.

OBJECTIVE: To compare measurements of cardiac output utilizing an improved transtracheal Doppler technology with measurements obtained using two-dimensional echocardiography. DESIGN: Prospective, descriptive study. SETTING: Cardiovascular intensive care unit at a university medical center. PATIENTS: Fourteen children ranging in age from 14 days to 3 yrs (mean 1.3 +/- .97 yrs) following surgery for complex congenital heart disease. INTERVENTIONS: Simultaneous cardiac output determinations using transtracheal Doppler and two-dimensional echocardiography were compared. Cardiac output was determined using measurement of blood velocity and diameter of the ascending aorta following surgery. Direct aortic diameter measurements made at operation were compared with measurements obtained by transtracheal Doppler, two-dimensional echocardiography and angiography. RESULTS: The mean difference in aortic root diameter between measurements made directly at operation and transtracheal Doppler was 5%, compared with 13% by two-dimensional echocardiography, and 21% by angiography, a significant difference by analysis of variance (F[3,31],p < .007). Post hoc comparisons demonstrated significant (p < .05) differences between echocardiography and angiographic aortic diameters. The mean difference between transtracheal Doppler and echocardiographic determination of cardiac output was 10.9% (t[10] = -1.37, p = .007). CONCLUSIONS: An improved transtracheal Doppler technology compares favorably with echocardiographic determination of cardiac output in infants and young children. This improved technology may provide a useful means to assess cardiac output and may allow titration of therapy in critically ill infants and children.

Pediatric and adult thoracic trauma: age-related impact on presentation and outcome.

UNLABELLED: To assess the impact of age on presentation and outcome, 2,415 cases involving blunt and penetrating thoracic trauma over an 8-year period were reviewed retrospectively from a single level I trauma center. Of the 2,073 patients alive on arrival, 79 were 12 years of age or less (children), 137 were 13 to 17 years of age (adolescent), 1,742 were 18 to 59 years of age (adults), and 115 were 60 years of age or more (elderly). Chi-square analysis was performed relative to presentation (blunt versus penetrating), need for thoracotomy, and hospital mortality. Although blunt thoracic trauma comprised 64/79 of children (81%) and 90/115 of the elderly (78%), penetrating thoracic trauma was more common for adolescents 79/137 (58%) and adults 1013/1742 (58%) (p < 0.05). There was no significant difference in need for thoracotomy among the four age groups after blunt thoracic trauma. For penetrating trauma, however, there was a significantly higher incidence of thoracotomy in children as compared with the other three age groups (p < 0.05). IN CONCLUSION: (1) Blunt injuries comprised a greater proportion of thoracic trauma in children and the elderly. (2) In this series, children with penetrating thoracic trauma underwent thoracotomy more frequently. (3) Hospital mortality appeared to be increased for the elderly. (4) Analyses of pediatric thoracic trauma must separate children from adolescent age groups.

Pediatric penetrating thoracic trauma: a five-year experience.

Penetrating thoracic trauma is managed nonoperatively in 85% of adult patients. We hypothesized that similar trauma in children would lead to proportionately more vital tissue damage and a higher rate of operative intervention. The pediatric penetrating thoracic trauma experience of a level one trauma center was analyzed over a five-year period. Data reviewed included circumstances of injury, Pediatric Trauma Score (PTS), interventions performed, and outcome. Of 61 children with thoracic trauma, 13 had penetrating injuries. Of these 13, seven were unintentional (five from firearms); the rest were caused by assaults. Seven patients (54%) underwent thoracotomy or laparotomy. All five patients with a PTS < 8 underwent surgical intervention, whereas only two of the eight patients with a PTS > or = 8 needed surgery (P < 0.05). There was one death. We reached the following conclusions: 1) Children with penetrating thoracic trauma are more likely to require surgical intervention than adults. 2) Penetrating thoracic trauma in children should elicit a thorough search for operative lesions. 3) About half these injuries are unintentional, and thus potentially preventable.

Rotational atherectomy in anomalous coronary arteries.

We describe two cases of high speed rotational atherectomy performed in patients with anomalous coronary anatomy. These procedures are performed with standard equipment requiring no modifications using a percutaneous femoral approach. We feel these cases clearly illustrate the facile application of this new technology to unusual anatomical situations.

Intramural ventricular fibroma in infancy: survival after partial excision in 2 patients.

Two infants with ventricular fibromas survived partial resection and have had satisfactory clinical results for more than 4 years. Partial excision is warranted when an unresectable tumor produces hemodynamic compromise. Long-term survival can be expected without complete resection.

Long-term results after surgical repair of incomplete endocardial cushion defects.

Since 1964, 56 children (mean age, 6.7 years) underwent repair of incomplete endocardial cushion defects. Forty patients had isolated ostium primum defects. Additional congenital defects were present in 17 patients (30%). All patients underwent patch closure of the ostium primum defect and 47 of 56 patients (84%) underwent mitral valvuloplasty. Hospital mortality was 1.8% (one death). Arrhythmias developed in 7 other patients in the early postoperative period, of which six were transient and resolved completely. One patient required early pacemaker placement for complete heart block. Cumulative follow-up was 378 patient-years. There were three late deaths (5.7%), and additional operations were required in 12 patients (22.6%). Seven of these 12 patients required mitral valve replacement for severe mitral regurgitation. The mean interval between initial repair and mitral valve replacement was 4.2 years, with only three valves needing replacement within 12 months. There was a significant correlation between the severity of mitral regurgitation before initial repair and subsequent need for mitral valve replacement. Late onset atrial arrhythmias have developed in 6 patients. Current functional status has been evaluated in 50 of 52 surviving patients and 88.5% are in NYHA class I, with the remainder in class II.

Surgical management of broncholithiasis.

Fifty-two patients (31 men and 21 women) were treated for complications of broncholithiasis between 1969 and 1984. Mean age was 50.8 years (range 26 to 74 years). Indications for operation included symptoms in 49 patients and an abnormal chest x-ray film in three. Broncholithectomy was initially attempted by thoracotomy in 40 patients and by bronchoscopy in 12. In the thoracotomy group broncholithectomy was successful in all patients, 32 of whom underwent pulmonary resection. Significant postoperative complications occurred in five patients (12.8%). There was one postoperative death (2.5%). In the bronchoscopy group broncholithectomy was successful in eight patients (67%); significant complications occurred in two and there were no early deaths. Subsequent thoracotomy was done in three of the four patients in whom bronchoscopic removal was unsuccessful. Follow-up averaged 76.5 months (range 6 to 183 months). The 15 year survival rate (Kaplan-Meier) for all patients was 75.1% and did not differ from a control group of patients. No patient in the thoracotomy group had recurrent complications of broncholithiasis. In contrast, complications recurred in three of the eight patients (37.5%) successfully treated by bronchoscopy. We conclude that broncholithectomy via thoracotomy is the preferred treatment, as the risks are low and the long-term results are excellent.

Results of the Damus-Stansel-Kaye procedure for transposition of the great arteries and for double-outlet right ventricle with subpulmonary ventricular septal defect.

From 1975 through 1982, the Damus-Stansel-Kaye procedure was performed on 20 patients with complete transposition of the great arteries (TGA) and on 4 with double-outlet right ventricle (DORV) and subpulmonary ventricular septal defect (VSD). The patients ranged from 6 days to 20 years old (median age, 13 months). Associated anomalies included atrial septal defect (24 patients), VSD (14), and others (25). Thirteen patients had had palliative operations previously. Of the 14 hospital deaths (58%), 13 occurred among the 17 patients with one or more risk factors: age less than 18 months, weight less than 10 kg, and left ventricular peak systolic pressure less than 75% of systemic pressure. Follow-up ranged from 12 to 87 months (mean, 51 months). One patient died of cardiac failure two years postoperatively, and 2 required conduit replacement at 40 and 50 months because of stenosis. All 9 survivors are free from major symptoms. The Damus-Stansel-Kaye repair is most suitable for patients with TGA or DORV with subpulmonary VSD who are older than 18 months, weight more than 10 kg, and have a "prepared left ventricle," and whose coronary artery anatomy precludes transplantation.