Glucose versus lactated Ringer's solution during pediatric cardiac surgery.

OBJECTIVE: Whether intraoperative fluid infusion should contain glucose during pediatric cardiac surgery remains controversial. This study was performed to compare the effects of glucose and glucose-free solutions on blood glucose and blood insulin levels during total repair of congenital heart diseases. DESIGN: Prospective randomized and blinded study. SETTING: Cardiovascular university center. PARTICIPANTS: Forty nondiabetic children, weight ranging from 4 to 10 kg, scheduled for cardiac surgical procedures requiring cardiopulmonary bypass (CPB) without total circulatory arrest. INTERVENTIONS: Group R (n = 20) was administered lactated Ringer's solution intraoperatively, and group G (n = 20) received 5% glucose. Fluids were infused at a rate of 3 mL/kg/h in the two groups from the induction of anesthesia to the end of the surgical procedure. Blood glucose and insulin were sampled before infusion (Tzero), before CPB (T1), 10 minutes after initiation of CPB (T2), 10 minutes after initiation of rewarming (T2), and at the end of the procedures (T4). Postoperatively, blood glucose was measured at the first, 12th, and 24th hours. MEASUREMENTS AND RESULTS: During the prabypass period, three children in group R had severe hypoglycemia (blood glucose < 40 mg/dL). After initiation of CPB, blood glucose increased in both groups, with a small difference at the end of the procedure. No infants in the two groups had blood glucose higher than 239 mg/dL. CONCLUSIONS: Glucose withdrawal during pediatric cardiac surgery induces threatening hypoglycemia during the prabypass period, and moderate intraoperative glucose administration (2.5 mg/kg/min) is not responsible for major hyperglycemia.

Bipolar intramyocardial electrogram from an implanted telemetric pacemaker for the diagnosis of cardiac allograft rejection.

Noninvasive detection of acute cardiac allograft rejection remains a challenge. Analysis of the epicardial electrogram transmitted by unipolar telemetric pacemaker can be of help in the detection of rejection with myocytolysis but is hampered by extracardiac factors. Instead, the contribution of a bipolar pacemaker for this purpose was studied. The bipolar peak-to-peak amplitude of epicardial electrograms (BPPA) from 25 patients implanted with a bipolar pacemaker at the time of heart transplantation was measured at the time of endomyocardial biopsies. BPPA was expressed as a percent of the baseline value. A voltage drop of more than 10% was considered an indication of rejection. Of 118 biopsies, 80 were free of rejection and 38 showed mild to moderate rejection (Grade 1A = 12; Grade 1B = 17; Grade 2 or 3 = 9). The mean value of BPPA was less for grade 2 biopsies (86.4 +/- 17%) than for biopsies with no or mild rejection (101.3 +/- 14.3% for Grade 0, 101.4 +/- 13.8% for Grade 1A, and 98.6 +/- 18% in Grade 1; P < 0.05). Diagnostic concordance between BPPA measurement and biopsy results increased with the histological severity of rejection (Grade 1A = 1/12, Grade 1B = 5/17, Grade > 2 = 7/9). Acute rejection was diagnosed with a sensitivity of 34% for Grade 1A, 46% for Grade 1B, and 78% for rejection episodes with myocytolysis (Grade > or = 2). Specificity remained approximately 90% for all histologic grades.(ABSTRACT TRUNCATED AT 250 WORDS)

Pulsatility improves hemodynamics during fetal bypass. Experimental comparative study of pulsatile versus steady flow.

BACKGROUND: The main advantage of pulsatile flow compared with steady flow during cardiopulmonary bypass is to prevent a rise in systemic vascular resistances. We hypothesized that pulsatile flow could overcome the progressive rise in peripheral and placental vascular resistances observed during fetal bypass and leading to progressive irreversible hypoxemia. METHODS AND RESULTS: A study was undertaken in 17 fetal lambs (110 to 140 days of gestation). Fetal bypass was established for a 30-minute period through right atrial and main pulmonary artery cannulation. The circuit had no oxygenator. Flow was delivered by a standard roller pump for the continuous study (group 1, n = 9) or by a centrifugal pulsatile pump for the pulsatile study (group 2, n = 8). Oxymetric and hemodynamic parameters, along with organ blood flow determined by radiolabeled microspheres counting, were recorded before (T1) and after 10 minutes (T2) and 30 minutes (T3) of bypass. SaO2 and PaO2 were significantly higher in group 2 than in group 1 at T2 but thereafter deteriorated similarly in both groups, whereas PCO2 remained unchanged. Pump flow in group 2 was significantly higher than in group 1 at T2 and T3 (957.6 +/- 49 and 1104 +/- 152 versus 437.6 +/- 23 and 467.8 +/- 43 mL/min, respectively). Systemic vascular resistances during pulsatile bypass were also significantly lower than in group 1 at T2 (402 +/- 12 versus 930 +/- 79 dynes/sec/cm-5) and T3 (374 +/- 60 versus 1017 +/- 192 dynes/sec/cm-5). At T2 and T3, all individual blood flows except the brain but including the placenta were statistically higher in group 2 than in group 1. Placental vascular resistances gradually increased during bypass in group 1 to reach 2.9 +/- 0.2 mm Hg.mL-1.min-1.kg-1 at T3 and remained approximately stable in group 2 during 30 minutes of pulsatile bypass, varying from 0.35 +/- 0.02 to 1.26 +/- 0.14 from T2 to T3 (P < .01). CONCLUSIONS: The data suggest that pulsatile flow for 30 minutes of bypass in a fetal lamb preparation temporarily prevents the progressive hypoxemia observed under steady-flow bypass. Pulsatile flow allows higher pump flow through a significant decrease in systemic vascular resistances. Individual organ blood flow, including placenta, was significantly higher under pulsatile bypass. With technical improvements in the design of pulsatile devices adapted to more physiological beat rates, pulsatility may become a valuable adjunct to overcome placental dysfunction observed during experimental fetal cardiac surgery.

[Peroperative ultrafiltration in complete repair of ventricular septal defect in infants]. / Ultrafiltration peropératoire lors de la correction complète de communication interventriculaire du nourrisson.

Ventricular septal defect in infants induces peroperative fluid overload (particularly extravascular lung water overload) which causes some morbidity after surgical closure of the defect. Thirty infants undergoing the conventional complete correction procedure were retrospectively compared with 32 infants operated upon using ultrafiltration at the end of the cardiopulmonary bypass. There was no difference between the two groups in biological data, haemodynamic parameters and either morbidity or mortality. Nevertheless, a clinical impression of smooth follow-up in patients with ultrafiltration encourages to carry out a prospective and randomized study.

[Aortic valve replacement using the Björk-Shiley valve. Long-term results (268 patients)]. / Remplacement valvulaire aortique par prothèse de Bjork-Shiley. Résultats à long terme (268 patients).

From 1974 till November, 1986, 268 adult patients aged from 15 to 84 years (11 p. cent over 70) underwent isolated aortic valve replacement by Björk-Shiley prosthesis. 81 p. cent of the prosthetic valves implanted were size 21 or over. The initial lesion was aortic stenosis (AS) in 40 p. cent, aortic regurgitation (AR) in 35 p. cent and aortic disease (AD) in 25 p. cent of the cases. The aortic valve lesions were degenerative (46 p. cent), rheumatismal (18 p. cent), congenital (12 p. cent), infective (19 p. cent including acute infective endocarditis) or dystrophic (7 p. cent) in origin. Pre-operatively, 54 p. cent of the patients were in NYHA functional class III and 14 p. cent in NYHA functional class IV. 7 p. cent presented with permanent atrial fibrillation. Mean pre-operative cardiac index was 2.49 1/mn/m2. Peri-operative mortality (up to 30 days) was 7.09 p. cent in both the 1974-79 period and the 1980-86 period; it was 3.4 p. cent in AS, 7.4 p. cent in AD and 10.7 p. cent in AR. The 249 survivors were followed up for a mean period of 5.3 years, or 1313 patient-years. 30 patients (11 p. cent) died subsequently (11 of prosthesis-related cause), giving an actuarial survival rate of 81.7 p. cent at 5 years and 71.4 p. cent at 10 years. 12 patients were reoperated upon, including 2 for prosthesis-related reasons (2.4 p. cent patient-years).(ABSTRACT TRUNCATED AT 250 WORDS)

[Surgical treatment of coarctation of the aorta in the infant less than a year old]. / Traitement chirurgical des coarctations de l'aorte chez le nourrisson de moins de un an.

Between 1972 and 1984, 141 infants of less than 12 months of age were operated upon for coarctation of the aorta. The abnormality was isolated in 41 cases (29 p. 100) and associated with ventricular septal defect (VSD) in 58 cases (41 p. 100), with transposition of the great vessels with or without VSD in 16 cases (11.3 p. 100), with cardiac valve disease with or without VSD in 11 cases (7.8 p. 100) or with miscellaneous intracardiac lesions in 15 cases (10.6 p. 100). Resection-anastomosis (Crafoord) was performed in 89 cases (63 p. 100), subclavian flap aortoplasty (Waldhausen) in 36 cases (26 p. 100) and dacron aortoplasty in 16 cases (11 p. 100). Cerclage of the pulmonary artery was combined with one or another of these operations in 65 cases (46 p. 100). Twenty-five patients (17.5 p. 100) died within 30 days of the operation, and 28 patients (24.7 p. 100 of those who survived surgery) died at a later stage. Three infants were lost sight of. Follow-ups ranged from 1 to 13 years (mean: 4.01 years). Fifteen infants (13.3 p. 100 of those who survived surgery) were reoperated upon for recurrence of the coarctation. Four infants (3.5 p. 100) now present with clinical signs of recoarctation and are awaiting treatment.

[Primary tumors of the heart. Diagnostic, anatomic and therapeutic aspects]. / Les tumeurs primitives du coeur. Aspects diagnostiques, anatomiques et thérapeutiques.

Primary cardiac tumours are rare. They are usually benign, the most common ones being left atrial myxomas. The authors report their experience of 16 cardiac tumours operated between 1978 and 1985. The patients were 12 adults and 4 children. The tumours were benign in 14 cases and malignant in 2 cases. Complete (14 cases) or incomplete ablation of the tumour was carried out under cardiopulmonary bypass with an early mortality of 6.25 per cent (1 case) and late mortality of 12.5 per cent (the two malignant tumours). The tumours were identified as myxomas in 11 cases, rhabdomyomas in 2 cases, fibroma in 1 case and malignant sarcomas in 2 cases. The average follow-up period of the 13 survivors is 30 months (range 4 months to 5 years) with excellent clinical and anatomical results. Clinical and paraclinical diagnosis of these tumours does not pose any major problems nowadays because of the reliability of the methods of investigation. However, the nature of the tumour is not always predictable and the operative findings are fundamental, not so much for the treatment which is relatively stereotyped but for the prognosis. Age is not a significant prognostic factor as excellent results may be obtained in the very young and the very old despite a sometimes precarious preoperative clinical condition. The benign or malignant nature of the tumour is the only real factor which affects the prognosis.

[Congenital aortic valve stenosis. Long-term results after valvulotomy]. / Rétrécissement aortique valvulaire congénital. Résultats éloignés après valvulotomie.

The cases of 73 patients undergoing valvulotomy for congenital valvular aortic stenosis between 1957 and 1982 were reviewed. Data was updated after recalling patients to the outpatient clinic and/or analysis of the results of a questionnaire sent to the patient's family doctor or cardiologist. Babies less than 12 months old at the time of surgery were excluded from the study. Operation consisted of valvulotomy under direct control with few associated procedures as the valvular lesion was isolated in 89 p. 100 of cases. 5 patients died in the first 30 postoperative days, an operative mortality of 5,4 p. 100. The follow-up period ranged from 1 to 25 years, with 15 patients having been followed up for over 10 years. 6 patients were reoperated with no operative mortality. 2 of whom have since undergone a second reoperation. Of the 59 patients not re-operated, 54 were class I and 5 class II of the NYHA. Of the latter group, 4 are candidates for aortic valve replacement for significant aortic regurgitation. The actuarial survival graph shows a 92.82 p. 100 probability of survival at 5 years, and 86.83 p. 100 at 10 years. Aortic valvulotomy remains a palliative operation which does not protect the patient from subsequent sudden death.

[Use of valved tubes in the treatment of ventriculo-pulmonary discontinuity. Long-term results]. / Utilisation des tubes valvulés pour le traitement des discontinuités ventriculo-pulmonaires. Résultats à distance.

Forty five patients, 2 months to 42 years of age, had valved tubes implanted for ventriculo-pulmonary discontinuity. The underlying malformations were: certain forms of Fallot's tetralogy (16 cases), transposition of the great arteries with ventricular septal defect and pulmonary stenosis (8 cases), truncus arteriosus (9 cases), double outlet right ventricle (6 cases), other malformations (4 cases). Hospital mortality (at 30 days) was 31% (14 cases). This was mainly due to technical difficulties related to the large number of palliative procedures and to irreversible pulmonary hypertension, present in 43% of cases with fatal outcomes. Thirty one patients were followed up for 6 months to 7 years (mean 3 +/- 1,6 years). There were 3 late deaths, one during reoperation for a residual shunt. All survivors underwent clinical assessment with hemodynamic control in 17 cases (15 routine control catheterisations). To date it has only been necessary to change one valved tube: a good result was obtained.

[Haemodynamic effects of dopamine, sodium nitroprusside and the association dopamine-sodium nitroprusside. Comparison of their effects after extra-corporeal circulation under deep hypothermia for congenital heart defects in infants and small children (author's transl)]. / Effets hémodynamiques de la dopamine, du nitroprussiate et de l'association dopamine-nitroprussiate. Evaluation aux mêmes doses chez le nourrisson et le petit enfant après cure de cardiopathie congénitale sous circulation extra-corporelle en hypothermie profonde.

Heart rate, cardiac index measured by thermodilution, systolic diastolic and mean arterial pressure, mean left and right atrial pressures, were measured immediately before and after 30 minutes of dopamine infusion at a rate of 7 micrograms/kg/minute, then after 30 minutes of nitroprusside infusion at a rate of 0.5 micrograms/kg/minute, and after 30 minutes of association dopamine-nitroprusside at the same doses. The statistical analysis shows that the best enhancement in the cardiac output is observed (P less than 0.01) after the association dopamine-nitroprusside, with a diminution of systemic vascular resistance (P less than 0.05) however less important than that observed with sodium nitroprusside alone (P less than 0.025).

[Anomalous origin of the left coronary artery from the pulmonary artery. Treatment by left subclavian-left main coronary artery anastomosis]. / Naissance anormale de la coronaire gauche à partir de l'artère pulmonaire. Traitement par anastomose de l'artère sous-clavière gauche au tronc coronaire gauche.

The technique of left subclavian-main left coronary artery is described as the treatment of anomalous origin of the left coronary artery from the pulmonary artery, without the aid of cardiopulmonary bypass, which, however, remains on standby. Through a left postero-lateral thoracotomy, the left main coronary artery is detached from the main pulmonary artery with a cuff of pulmonary wall after lateral clamping of the pulmonary artery. Tapes are encercling the pulmonary artery and the descending thoracic aorta, making them ready for an eventual connection to the standby bypass, in case the coronary clamping is not well tolerated. The anastomosis between the left subclavian artery dissected free and the prepared left main coronary artery is then possible and easy even in a small infant. This technique has been used in three infants aged three to thirty months without any mortality nor particular morbidity.