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D Dacar

Publications and source records attributed to D Dacar.

At least 37 records · Page 2Linked to original sources
PubMed1995

Sonographically guided cannula positioning for extracorporeal membrane oxygenation.

Drainage problems due to catheter malpositioning are acutely life-threatening in patients undergoing extracorporeal membrane oxygenation. In order to reduce these complications we introduced sonographically guided catheter positioning. We compare the outcome in a group of patients with blind cannula positioning to that in a group with sonographically guided catheter positioning. Our results show that neonates and young infants especially are at high risk of drainage problems due to catheter malposition and that their outcome could be markedly improved by introducing sonographically guided cannula insertion.

Catheterization↗
PubMed1995

Continuous blood density measurements and volume changes during extracorporeal circulation in patients undergoing cardiac surgery.

The changes of blood volume and transcapillary fluid shifts during extracorporeal circulation (ECC) was examined using continuous measurements of blood density by the mechanical oscillator technique. Sixteen patients (1 female, 15 male) with a mean age of 61.4 years (+/- 7.6 years, 47-70 years) undergoing coronary artery bypass surgery were included in this study. The equipment for continuous measurement of the blood density (DPRT by Paar/Austria) was installed at the arterial line of the heart-lung bypass. Higher-precision discrete measurements of some parameters used the DMA 55 equipment produced by the Paar company. Measurements were taken at 37 degrees C. In 11 patients the transcapillary volume loss (difference of total volume between beginning and end of ECC) during heart-lung bypass (mean observation period of 55 min (+/- 16 min, 28-82 min) was found to be 870 ml/m2 body surface area (BSA) (+/- 360 ml, 290-1560 ml/m2) by the dilution method using the priming solution at the beginning and 500 ml lactated Ringer's solution added at the end of the ECC. The calculated volume shift using the "double density method", which takes into account blood density, plasma density, and hematocrit, amounted to 830 ml/m2 BSA (+/- 200 ml, 450-1210 ml/m2). The density of the transcapillary volume loss into the interstitial layer was calculated and found to be 1.0026 g/ml (+/- 0.0017 g/ml, 1.0003-1.0063 g/ml). A significant difference of transcapillary volume shift correlated with the administered catecholamine (dopamine, dobutamine) dosage postoperatively. Without catecholamine this difference was 260 ml/m2 BSA, with 3 microns/kg/min dopamine it rose to > 500 ml/m2 BSA.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1995

Inhaled nitric oxide versus inhaled prostacyclin and intravenous versus inhaled prostacyclin in acute respiratory failure with pulmonary hypertension in piglets.

This study was a prospective, randomized design to compare oxygenation and pulmonary hemodynamics between inhaled nitric oxide (NO) and inhaled prostacyclin (PGI2), and between inhaled and i.v. PGI2 in acute respiratory failure with pulmonary hypertension. Acute respiratory failure with pulmonary hypertension was induced in 12 piglets weighing 9-12 kg by repeated lung lavages and a continuous infusion of the stable endoperoxane analogue of thromboxane. Thereafter the animals were randomly assigned either for NO or PGI2 application. All animals were treated with different concentrations of NO or different doses of PGI2 applied i.v. and inhaled in random order. Continuous monitoring included ECG, central venous pressure (CVP), mean pulmonary artery pressure (MPAP), mean arterial pressure (MAP), arterial oxygen saturation (SaO2), and mixed venous oxygen saturation (SvO2) measurements. NO inhalation of 10 ppm resulted in a significant increase in PaO2/fraction of inspired oxygen (FiO2) from 7.8 +/- 1.34 kPa to 46.1 +/- 9.7 kPa. MPAP decreased significantly from 5.1 +/- 0.26 kPa to 3.7 +/- 0.26 kPa during inhaled NO of 40 ppm; i.v. infusion of PGI2 slightly increased oxygenation parameters. A significant increase in PaO2/FiO2 up to 32.4 +/- 3.1 kPa was observed during PGI2 aerosol delivery (p < 0.01); i.v. PGI2 decreased MAP from 11.5 +/- 0.39 kPa to 9.8 +/- 0.66 kPa (p < 0.05) and MPAP from 5.8 +/- 0.53 kPa to 4.5 +/- 0.66 kPa, respectively (p < 0.05). PGI2 aerosol delivery significantly decreased the MPAP to 3.7 +/- 0.53 kPa (p < 0.05) without influencing the MAP.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗
PubMed1995

[Total cavo-pulmonary connection as a therapeutic principle in anatomical and functional univentricular heart].

The original Fontan operation was employed for patients with tricuspid atresia, but its application has been extended to a broad spectrum of congenital cardiac defects with a functional or anatomical single ventricle. From 1989 to 1995, 35 patients (23 males, 12 females) underwent a modified Fontan procedure; their age ranged from 14 months to 15 years (mean 5.1 a). Indications for operation were the following: D(S)ILV = 16, TA = 9, MA = 3, TGA with straddling AV-valve = 2, DORV = 4 and criss-cross heart = 1. The same surgical technique was utilized in all patients with redirection of the systemic venous return by means of a bidirectional cavopulmonary anastomosis and an intraatrial baffle, adaptable to all the various forms of underlying anatomy. Associated anomalies such as dextrocardia, coarctation, anomalous systemic or pulmonary venous return, subaortic stenosis and situs anomalies were present in 26%, 9%, 26%, 9%, and 20%, respectively. 12 patients were presumed to be at high risk and underwent a two-stage procedure (n = 7 bidirectional Glenn preceding the definitive repair and n = 5 a fenestration of the intraatrial baffle). Risk factors in our group of patients were: age under 2 years, abnormal systemic venous drainage, stenotic pulmonary arteries, PVR over 2 Wood units, mPAP over 15 mmHg, AV-valve incompetence, subaortic obstruction and ventricular dysfunction. Two patients had failure of the total cavo-pulmonary connection necessitating the take-down to a bidirectional Glenn anastomosis in the early postoperative period, with one death. Hospital mortality was 24% (n = 8). One child did not survive complications following the fenestration closure 4 months postoperatively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

Proximal and tracheal airway pressures during different modes of mechanical ventilation: an animal model study.

OBJECTIVE: To determine the differences between the mean proximal and tracheal airway pressures during 3 different modes of mechanical ventilation (MV) in an animal model of acute cardiac failure (CF) and respiratory failure (RF). DESIGN: Prospective, randomized, cross-over design. SETTING: University research laboratory. SUBJECTS: Twelve young pigs weighing 10-16 kg. INTERVENTIONS: The experimental protocol consisted of 3 stable 30 min conditions: when ventricular and pulmonary function was normal (control), after the induction of acute cardiac failure by a beta-blocking agent and after respiratory failure induced by repeated lung lavages. Modes of MV included controlled mechanical ventilation (CMV), high-frequency oscillation (HFO), and high-frequency jet ventilation (HFJV). MEASUREMENTS AND RESULTS: The tracheal mean airway pressure (P(aw)) was measured at the distal port of the Hi-lo jet tube using an air-filled pressure transducer. The mean transpulmonary P(aw) increased significantly from 0.41 +/- 0.14 kPa during the control period to 1.15 +/- 0.17 kPa (P < 0.0001) during the RF period. In all study periods both the proximal and tracheal P(aw) were lowest during HFJV. There was no difference between the proximal and tracheal P(aw) during CMV and HFJV throughout the protocol. In the cardiac and respiratory failure periods the proximal P(aw) (CF, 1.45 +/- 0.08 kPa; RF, 3.13 +/- 0.27 kPa) was significantly higher than the tracheal P(aw) (CF, 1.04 +/- 0.09 kPa, P < 0.01; RF, 2.18 +/- 0.3 kPa, P < 0.01) with HFO. When ventilated by HFO, the mean external oscillatory amplitude was 4.33 +/- 0.14 kPa and the intratracheal oscillatory amplitude was only 0.49 +/- 0.06 kPa (P < 0.0001). CONCLUSION: HFJV provides adequate respiratory support at lower P(aw) than CMV and HFO. Proximal P(aw) closely reflects tracheal P(aw) during CMV and HFJV. However, with HFO great pressure differences between the proximal and tracheal airways are evident. Therefore, additional intratracheal airway pressure monitoring seems to be very useful for optimizing ventilator settings during HFO.

Acute Disease↗
PubMed1994

Prolonged extracorporeal organ support in a 2-year-old boy after cardiac surgery.

A case report of a 2-year-old boy who developed severe post-operative low cardiac output, sudden cardiac arrest and consecutive multiple organ system failure after open heart surgery is described. Initially the hemodynamic situation was stabilized by extracorporeal membrane oxygenation (ECMO) combined with continuous hemofiltration (CHF) carried out for 7 days. Continuous veno-venous hemofiltration (CVVH) was necessary for further 17 days. One episode of plasmapheresis restored transiently a severe post-operative coagulopathy and enabled the removal of the pulmonary artery catheter and the chest tubes.

Cardiac Output, Low↗
PubMed1994

Hemodynamic effects of different modes of mechanical ventilation in acute cardiac and pulmonary failure: an experimental study.

OBJECTIVE: To determine the hemodynamic effects of four different modes of mechanical ventilation in an animal model of acute cardiac and pulmonary failure. DESIGN: Prospective, randomized, crossover design. SETTING: University research laboratory. SUBJECTS: Twelve piglets weighing 10 to 16 kg. INTERVENTIONS: The experimental protocol consisted of three stable 30-min periods: when ventricular and pulmonary functions were normal (control), after the induction of acute cardiac failure by the administration of a beta-adrenergic receptor blocker, and after pulmonary failure induced by repeated lung lavage. Modes of mechanical ventilation included controlled mechanical ventilation, high-frequency oscillation, synchronized high-frequency jet ventilation, and external negative pressure oscillation combined with pressure support ventilation. Each mode of respiratory support was randomly and sequentially applied to each animal with the assessment of cardiopulmonary function at the end of each period. MEASUREMENTS AND MAIN RESULTS: Continuous monitoring included electrocardiogram, right atrial, left ventricular end-diastolic, pulmonary arterial, intrathoracic aortic, arterial, esophageal, and transpulmonary pressures and arterial and mixed venous oxygen saturation measurements. In addition, cardiac output using the thermodilution technique was measured intermittently. Whereas in the control period cardiac index was significantly (p < .05) higher during synchronized high-frequency jet ventilation (193 +/- 19.3 mL/kg/min) than during controlled mechanical ventilation (151 +/- 12.1 mL/kg/min) and high-frequency oscillation (151 +/- 18.1 mL/kg/min), there was no significant hemodynamic difference between the four modes of mechanical ventilation in the cardiac and pulmonary failure periods. In the pulmonary failure period, transpulmonary pressure was significantly higher during high-frequency oscillation (7.1 +/- 1.6 mm Hg) than during controlled mechanical ventilation (5.6 +/- 0.6 mm Hg), high-frequency ventilation (4.1 +/- 0.4 mm Hg), and external negative pressure oscillation combined with pressure support ventilation (5.3 +/- 0.5 mm Hg). CONCLUSIONS: Synchronized high-frequency ventilation improves cardiac performance in control conditions. No hemodynamic difference is present between the four modes of mechanical ventilation in the cardiac and pulmonary failure periods. External negative pressure oscillation combined with pressure support ventilation has moderate hemodynamic advantages over controlled mechanical ventilation and high-frequency oscillation in different clinical settings, but it also results in a deterioration of pulmonary gas exchange during the pulmonary failure period.

Animals↗
PubMed1994

[Total cavopulmonary connection in complex heart defects with a single functional ventricle].

Nineteen children aged between 1.5 and 9.8 years (10 patients younger than 4 years) underwent total cavopulmonary connection (TCPC) for complex congenital heart defects other than tricuspid atresia. Diagnoses included double inlet left ventricle (n = 11), transposition of the great arteries with a large ventricular septal defect (n = 4), double outlet right ventricle (n = 2), congenitally corrected transposition of the great arteries with a large ventricular septal defect (n = 1) and criss-cross heart (n = 1). Two patients had situs ambiguous with polysplenia syndrome and four patients had anomalous systemic venous return. Thirty-six palliative procedures were performed in 15 patients before TCPC. The patients were selected according to the selection criteria of Choussat and Fontan. Four patients (21%) died between the 1st and 12th postoperative day because of low cardiac output syndrome (n = 2), supraventricular tachycardia unresponsive to treatment (n = 1), and cerebral edema (n = 1). In one patient take down of TCPC was performed for persistent low cardiac output syndrome. Four of these five patients were younger than 4 years old and had one or more additional risk factors. Postoperative complications were persistent pleural or pericardial effusions (n = 4), transient supraventricular tachycardia (n = 2), and low cardiac output syndrome (n = 1). There was no late death. Follow-up was available in 12 patients. At a mean follow-up of 15 +/- 9 months, nine patients are in NYHA-functional class I, two patients in class II, and one patient in class III. Postoperative cardiac catheterization revealed satisfactory results in seven of eight patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Anastomosis, Surgical↗
PubMed1993

Atypical presentation of Kawasaki disease in an infant.

A 7-month-old male infant with clinical symptoms of severe toxic shock syndrome died on day 9 of illness. At autopsy, demonstration of coronary vasculitis together with thrombosis of the left coronary artery revealed the true diagnosis of atypical Kawasaki disease. The marked similarity in many clinical features makes the distinction between these two diseases difficult when atypical clinical presentation of Kawasaki disease is present.

Coronary Vessels↗
PubMed1993

Twenty-four years' implant duration of the aortic Starr-Edwards Silastic ball prosthesis: a valve of the past?

Six years after the first aortic valve replacement with the Starr-Edwards Silastic ball prosthesis at Oregon Health Sciences University, the model 1260 was implanted in a 44-year-old patient at our department. During 24 years no signs of dysfunction, thromboembolism, thrombosis, periprosthetic leaks or hemolysis were observed. Material test showed no signs of fatigue. The dimension of the Silastic poppet was found to be one millimeter less than the original specifications of these poppets and there were some lipid infiltrations. Functionally the poppet was found to be nonvariant. Histologic findings detected focal hyalinization and giant cells without signs of acute inflammation or ulceration. With regard to its reliability and durability, the Starr-Edwards valve prosthesis should not be viewed with disfavor.

Adult↗
PubMed1993

Prospective evaluation of clinical scoring systems in infants and children with cardiopulmonary insufficiency after cardiac surgery.

OBJECTIVE: To document severity of illness and to evaluate the predictive value of clinical scoring systems in infants and children with cardiopulmonary insufficiency after cardiac surgery. DESIGN: Prospective study with follow up to hospital discharge. SETTING: A multidisciplinary pediatric ICU in a University Hospital. PATIENTS: Between 1/1989 and 4/1992 441 infants and children with congenital heart disease underwent open heart surgery. 128 of these patients developed postoperative cardiopulmonary insufficiency and were entered into this study. METHODS: Data relevant to the Acute Physiologic Score for Children (APSC), Pediatric Risk of Mortality (PRISM), Therapeutic Intervention Scoring System (TISS) and Organ System Failure (OSF) score were collected in all patients during the first 4 days of postoperative intensive care. RESULTS: The mean age of the patients was 1.5 +/- 0.2 years. The mean duration of mechanical ventilation and ICU care was 6.2 +/- 0.6 and 8.1 +/- 0.7 days, respectively. On the first postoperative day the mean APSC and PRISM scores of survivors and nonsurvivors were 13.9 +/- 1.3 vs 24.5 +/- 1.3 (p < 0.001) and 6.1 +/- 0.5 vs 19.6 +/- 1.9 (p < 0.001), respectively. The mean TISS and OSF scores of survivors and nonsurvivors were 46 +/- 0.8 vs 57.8 +/- 1.4 (p < 0.001), and 2.2 +/- 0.2 vs 3.4 +/- 0.2 (p < 0.001), respectively. The overall hospital mortality rate was 9.9%, the hospital mortality rate of patients with postoperative cardiopulmonary insufficiency 34%. Patients with an APSC score < 10 and a PRISM score < 5 had a survival rate of 100%, whereas patients with an APSC score > 30 and a PRISM score > 25 had a mortality rate of 100%. The area under the receiver operating characteristic (ROC) curve for APSC, PRISM and TISS was 0.847, 0.826 and 0.793, respectively. CONCLUSION: APSC, PRISM and TISS describe accurately severity of illness in infants and children with cardiopulmonary insufficiency after cardiac surgery and all scores identify those patients at increased risk for mortality.

Cardiac Output, Low↗
PubMed1992

Mechanical support of the left ventricle in ischemia induced left ventricular failure: an experimental study.

OBJECTIVE: this study compares the hemodynamic effects of intra-aortic balloon pumping (IABP), left ventricular assist device (LVAD), and extracorporeal membrane oxygenation (ECMO) in left ventricular failure in pigs. METHODS: In 29 pigs weighing 12 +/- 0.7 kg left ventricular failure was induced by ligating the left anterior descending coronary artery. Eight animals served as controls. Eight pigs were treated by IABP, seven by LVAD, and six by ECMO. The study period lasted four hours. Hemodynamic and oxygen transport/uptake parameters were measured continuously or intermittently. RESULTS: Six animals of the ECMO and LVAD groups survived the 4 hour period, but only 3 and 4 animals of the IABP and control groups survived (p less than 0.05). Cardiac index decreased about 48% and 22% in the control and IABP groups (p less than 0.05), whereas there was only a slight decrease in the ECMO (9%) and LVAD (14%) groups. Oxygen delivery fell significantly in the control and IABP groups (p less than 0.05), compared with only a slight change in the LVAD and ECMO groups. CONCLUSION: ECMO is the most effective system for temporary circulatory support in severe ventricular failure. LVAD maintains cardiac output when pulmonary blood flow is provided. IABP is less efficient in supporting the failing heart, especially in the presence of severe ventricular arrhythmias.

Animals↗
PubMed1990

Extracorporeal CO2 removal in a lung lavage induced respiratory distress syndrome.

Ten pigs with experimental respiratory distress syndrome were treated by extracorporeal CO2 removal (ECCO2-R) combined with low frequency positive pressure ventilation (LPPV). After lung damage had been induced by repeated lung lavages a PEEP trial was conducted in order to find the appropriate PEEP for the damaged lungs. This PEEP was then applied during the ECCO2-R/LPPV period. Blood gas values improved significantly on extracorporeal bypass within a short time (pre-bypass paO2: 54.2 +/- 3.7 vs 168.5 +/- 31.6 mmHg after 15 min on bypass, p less than 0.001) and were kept constant during the next 4 hours. Minute ventilation (MV) was reduced from 4.01 +/- 0.31 to 0.74 +/- 0.07 l/min (p less than 0.0001), FiO2 of the ventilator from 1.0 to 0.46 +/- 0.08 (p less than 0.0001) whereas FiO2 of the membrane lung (ML) was not changed significantly (FIO2ML 0.59 +/- 0.07 vs 0.53 +/- 0.06). During controlled mechanical ventilation (CMV), comparable adequate gas exchange was only achieved at a significantly higher mean airway pressure (Paw 14.1 +/- 0.08 vs 21.2 +/- 0.47 cmH20, p less than 0.0001). Hemodynamic variables did not change significantly during bypass time. ECCO2-R/LPPV driven by a simple renal perfusion system allows adequate gas exchange in experimental respiratory failure.

Animals↗
PubMed1985

[Surgical treatment of the isolated form of interrupted aortic arch].

We report on a 14-years old boy with isolated interruption of the aortic arch (type B). By the use of extracorporal circulation complete relief could be achieved by interposing a large Dacron tube. Follow up restudy demonstrated a normotensive patient without residual gradient of the systemic blood pressure.

Adolescent↗
PubMed1985

[Initial clinical experiences with the fibrin adhesive Beriplast in heart surgery].

Fibrin glue Beriplast was used during cardiovascular surgery in 97 patients. The fibrin seal was used for hemostasis on anastomoses, patches and suture lines. Moreover, the glue was applied for epicardial fixation of aorto-coronary vein grafts to prevent postoperative graft kinking. Following extrapleural ligation of patent duct in premature infants, the parietal pleura was fastened to the thoracic wall to prevent extrapleural pneumothorax or hemorrhage. After accidental dissection of the thoracic duct in infants, leakage of chyle could be sealed successfully in 6 cases. Hemorrhage from the sealed surfaces of suture lines was not observed. Viral hepatitis occurred postoperatively in 2 patients (3% of the operations for acquired heart disease), both of whom had also received clotting factor concentrate and blood transfusion because of postoperative hemorrhage not related to fibrin sealed surfaces. A causal relation between the hepatitis and application of the pasteurized fibrin glue seems very unlikely. Although fibrin glue certainly cannot replace the surgical suture, it appears to be a valuable aid under special conditions.

Adult↗