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M Leijala

Publications and source records attributed to M Leijala.

At least 37 records · Page 2Linked to original sources
PubMed1994

Renal transplantation in children with emphasis on young patients.

We report the results of 41 consecutive renal transplantations performed on 39 children (median age 2.7 years). Twenty-six recipients were less than 5 years old. Twenty-one recipients (13 under the age of 5 years) received cadaver (CAD) grafts. All grafts except 2 were from adult donors and were placed extraperitoneally. Patients were on triple immunosuppression (cyclosporine plus azathioprine plus methylprednisolone). Mean follow-up time was 2.3 years. No vascular and only one ureteral complication was seen. Acute tubular necrosis occurred in 3 patients (7.3%). No grafts were lost due to acute rejection. Three-year patient survival and 1-year graft survival were 100%. The overall 3-year actuarial graft survival was 86%. Three-year survival of grafts from living-related donors (LRD) was 92% and that of CAD grafts 75%. In recipients younger than 5 years, 3-year LRD graft survival was '89% and CAD graft survival 73%. No significant differences in graft survival between recipients of different age groups or between LRD and CAD grafts were found. We conclude that results of renal transplantation in children under 5 years of age are comparable to those of older children, even using CAD grafts, when adult donors and triple immunosuppression are used.

Adolescent↗
PubMed1994

Oxygen consumption following pediatric cardiac surgery.

Metabolic responses during recovery from cardiac operations for various congenital heart defects were studied in 30 mechanically ventilated pediatric patients in two groups: infants 1 year or less (group I) and children more than 1 year old (group II). Oxygen consumption (VO2) and carbon dioxide production (VCO2) were measured using a pediatric metabolic monitor intermittently after induction of anesthesia, after skin closure, 2 to 4 hours postoperatively, and on the first postoperative morning in the pediatric intensive care unit. Energy expenditure and respiratory quotient were determined from respiratory gas measurements. Rectal and skin temperatures and hemodynamic variables were recorded at the same time. VO2 increased during rewarming 2 to 4 hours after the operation by 12 +/- 15% in group I and by 24 +/- 19% in group II, while rectal temperature increased by 2.0 +/- 1.2 degrees C and 1.8 +/- 1.4 degrees C, respectively. No further increase in VO2 occurred until the first postoperative morning. A hypermetabolic response was not seen in all cases despite marked thermal changes. High-dose fentanyl anesthesia partly explains the low responses. On the other hand, low cardiac output may also compromise oxygen supply. Sixty-three percent of infants were treated for cardiac failure before surgery and 75% needed inotropic support immediately after the operation. Low central venous oxyhemoglobin saturation values (ScvO2 < 60%) were observed during rewarming, indicating an increase in oxygen extraction secondary to an increased oxygen demand in the brain during recovery from anesthesia, and a low cardiac output or delayed restoration of cerebral blood flow after CPB and deep hypothermia.

Anesthesia, Intravenous↗
PubMed1994

Thirty years of renal transplantation in Helsinki.

During triple-drug immunosuppression, consisting of azathioprine, steroids, and cyclosporine, the number of acute rejections was low. Close monitoring of the patient and the graft during the early posttransplant weeks with regular cytological and histological analyses was the cornerstone of early diagnosis and a favorable outcome of acute rejection. Genetic homogeneity of our patient population, third-party transfusion program, and use of well HLA-matched kidney grafts may have been additional factors behind the low rate of acute rejection. Acute rejection within the first three postoperative months did not predispose the renal graft to chronic rejection in the long term. The histologically determined allograft damage index was a reliable predictor of future graft survival. Recipients with systemic diseases such as diabetes and amyloidosis, as well as elderly patients, could be transplanted safely with results only slightly inferior to those achieved with primary kidney disease. Results in diabetic recipients have steadily improved, encouraging the continuation of critical evaluation of the patients' pretransplant status and the preference for cadaveric transplants. Renal transplantation in small children yielded superior patient and graft survival rates. We consider the use of living donors justifiable in these cases. The five million population of Finland offers an ideal size for a transplant center. Continuous education of medical personnel and the general public is crucial for the cadaver transplant program.

Adolescent↗
PubMed1993

Metabolic effects of corrective surgery in infants and children with congenital heart defects.

We have measured oxygen consumption and carbon dioxide production by indirect calorimetry in 25 infants and children immediately before and after surgical correction of congenital cardiac malformations. Surgical correction of the cardiac defect caused a decrease in oxygen consumption towards normal. Greatly increased oxygen consumption values were observed before surgery in the infants with a large left-to-right intracardiac shunt and heart failure and the highest reduction in metabolic rate, up to 43%, was observed in these infants. The results indicate that corrective surgery for congenital cardiac malformations reduces the load on the cardiopulmonary system immediately after operation.

Body Weight↗
PubMed1992

Superior vena caval and mixed venous oxyhemoglobin saturations in children recovering from open heart surgery.

Simultaneous superior vena caval (Scvo2) and mixed venous (Svo2) oxyhemoglobin saturation values in 15 children recovering from open heart surgery were compared to assess the value of superior vena caval blood samples in monitoring systemic oxygen supply/demand balance. Samples were obtained immediately following the operation and postoperatively every morning for 4 days. During the 4-day study period, the patients' cardiopulmonary functions improved, allowing partial weaning from respiratory and cardiovascular support. The lowest values of superior vena caval (46.7 +/- 8.4%) and mixed venous (63.7 +/- 10.9%) oxyhemoglobin saturation were measured immediately after the operation. At this time, 6 patients had abnormally low Scvo2 values, but normal Svo2 values. Both Scvo2 and Svo2 increased; the difference between them decreasing significantly during the study period (P less than 0.001). The results show that Scvo2 is consistently lower than Svo2 in children recovering from open heart surgery. This difference may be secondary to residual intracardiac left-to-right shunting of blood or to altered distribution of systemic blood flow. The saturation difference between the two venous samples decreases during postoperative recovery, making a superior vena caval blood sample an inadequate substitute for a mixed venous blood sample in calculating derived cardiopulmonary variables intended to reflect the function of the body as a whole. Because Scvo2 was frequently subnormal while Svo2 was in the normal range, monitoring of Svo2 could not be reliably used to rule out oxygen supply/demand imbalance during the early postoperative period in these patients.

Age Factors↗
PubMed1992

Bronchoscopy during the first month of life.

During the 6-year period from 1984 to 1989, 196 bronchoscopies were performed on 132 neonates. The indications were grouped into four categories: (1) difficulties in artificial ventilation or failure to wean the baby from the ventilator (52); (2) other respiratory difficulties (52); (3) audible stridor (16); and (4) routine preoperative or postoperative examination of esophageal atresia patients (12). The most common finding was laryngomalacia or tracheomalacia (31). Other findings were: obstructing tracheal or bronchial granulation or stricture (23), obstructing mucous plug (22), grave tracheobronchitis (11), tracheoesophageal H-fistula (5), laryngeal perforation (3), congenital laryngeal stenosis (2), and complete laryngotracheoesophageal cleft (1). Four patients had miscellaneous pathology. The findings were normal in 30 patients. A therapeutic procedure was included in 99 of the 196 bronchoscopies. Seven serious complications occurred during the operative bronchoscopies, two of them requiring immediate pulmonary surgery. All complications were successfully managed. In contrast, no complications occurred in the 97 purely diagnostic bronchoscopies. In experienced hands, bronchoscopy of the newborn is a safe and useful examination. Complications occur when therapeutic procedures are included. Therefore, operative bronchoscopy should only be performed in conditions in which immediate thoracotomy and pulmonary surgery can be performed.

Bronchial Diseases↗
PubMed1992

Spontaneous breathing and total body oxygen consumption in children recovering from open-heart surgery.

The effects of withdrawal of ventilatory support on cardiopulmonary function, oxygen consumption and carbon dioxide production were assessed in 25 infants and children within seven days (2.9 +/- 2.5 days; mean +/- SD) of an open heart operation, during weaning from ventilatory support. The average age of the patients was 3.4 +/- 3.5 years and weight 12.4 +/- 8.3 kg. Heart rate, blood pressure, arterial and central venous blood gas values, and oxyhemoglobin saturations were measured during controlled mechanical ventilation and during spontaneous breathing with continuous positive airway pressure. Simultaneously, VO2 and VCO2 were measured using indirect calorimetry. Withdrawal of ventilatory support effected an expected, significant decrease in arterial pH (7.42 +/- 0.10 to 7.37 +/- 0.06; p less than 0.001) and an increase in PaCO2 (34 +/- 6 to 40 +/- 5 mm Hg; p less than 0.0001), while arterial blood oxyhemoglobin saturation, heart rate, and blood pressure remained unchanged. A significant increase in central venous oxyhemoglobin saturation (67.9 +/- 11.9 to 74.8 +/- 8.3 percent; p less than 0.001) indicated improvement in systemic blood flow during spontaneous breathing. Average VO2 and VCO2 did not change significantly. A decrease in VO2 by more than 5 percent was seen in seven patients, an increase by more than 5 percent in nine, and a change within +/- 5 percent in nine patients. The change in VO2 was inversely related to the difference between measured and expected VO2 during mechanical ventilation (r = -0.73) and to body temperature (r = -0.69). The results indicate that factors other than the oxygen uptake by the respiratory muscles may have significant effects on total body VO2 in infants and children after open-heart surgery. Therefore, monitoring of VO2 during withdrawal of ventilatory support may not be an accurate indicator of respiratory work and oxygen cost of breathing in these patients.

Carbon Dioxide↗
PubMed1991

Lung mechanics and airway pressure transmission in infants after open heart surgery.

To evaluate the effects of positive airway pressure on lung mechanics and airway pressure transmission into the intrathoracic space, airway and intrathoracic pressure were recorded during stepwise lung inflation in 17 infants undergoing open heart surgery during the first year of life. Eleven of the 17 patients had cuffed tracheal tubes allowing calculation of lung and chest wall compliance. In 7 of these 11 patients, lung inflation to 2.5 ml/kg above functional residual capacity produced an improvement in initially low lung compliance. This volume increment required elevation of airway pressure by 4-11 cm H2O above ambient. Further lung inflation to 10 ml/kg did not effect an improvement in lung mechanics. In the remaining patients, initial lung compliance was high and remained unchanged throughout the range of lung inflation. Transmission of pressure into the intrathoracic space averaged 47 +/- 9% (mean +/- SD) and ranged from 33% to 61% when airway pressure was 10-15 cm H2O. The results indicate that the use of moderately elevated airway pressure is required to optimize lung distensibility in most infants immediately after open heart surgery. When evaluating circulatory effects of elevated airway pressure, assumption of a 50% pressure transmission is appropriate for clinical purposes. However, the observed wide range of pressure transmission warrants careful hemodynamic monitoring during continuous positive pressure breathing.

Female↗
PubMed1991

Breathing circuit respiratory work in infants recovering from respiratory failure.

OBJECTIVE: To compare cardiopulmonary function during spontaneous breathing with three continuous-flow breathing circuits. The major difference between these circuits was the degree of flow resistance offered by the exhalation valve. DESIGN: Randomized crossover trial. PATIENTS: Twelve infants less than 12 months of age recovering from respiratory failure of variable etiology. Only patients weighing 3 to 10 kg were studied. INTERVENTIONS: The patients were connected to each respiratory circuit in a random sequence, with 15 min allowed for equilibration before assessment of cardiopulmonary function. Airway pressure (Paw) and FIO2 were maintained unchanged. MEASUREMENTS AND MAIN RESULTS: Ventilation, gas exchange, or circulatory function were not altered significantly by changing the breathing circuit. However, Paw and esophageal pressure fluctuations were altered and were largest during breathing with the circuit that had an exhalation valve with high-flow resistance. The Paw fluctuation recorded while the patient was breathing with the flow-resistor circuit increased with weight and exceeded 2 cm H2O in all patients weighing greater than 4.5 kg. Paw fluctuation could be decreased by greater than 2 cm H2O in ten of 12 patients by using the threshold-resistor circuit. CONCLUSIONS: The results indicate a need for evaluating the characteristics of respiratory circuits used for spontaneous breathing in infants and children, to avoid unnecessary equipment-related increase in respiratory work.

Airway Resistance↗