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J Bonatti

Publications and source records attributed to J Bonatti.

42 records · Page 3Linked to original sources
PubMed1995

Dopamine-1-receptor stimulation and mucosal tissue oxygenation in the porcine jejunum.

OBJECTIVE: To evaluate the effects of dopamine-1-receptor stimulation on intestinal mucosal tissue oxygenation. DESIGN: Prospective, experimental, controlled trial. SETTING: Animal research laboratory. SUBJECTS: Anesthetized domestic pigs (30 to 45 kg). INTERVENTIONS: A small segment of the jejunal mucosa and serosa was exposed by midline laparotomy and antimesenteric incision. Fenoldopam, a selective dopamine-1-receptor agonist, was infused in steps, exponentially increasing from 0.6 to 9.6 micrograms/kg/min via a central venous catheter (n = 8, fenoldopam group), whereas a second group (n = 6, saline group) was only given the solvent. MEASUREMENTS AND MAIN RESULTS: Systemic hemodynamics as well as systemic and jejunal acid base and blood gas variables were measured using an arterial catheter, a thermodilution pulmonary artery catheter, and a jejunal venous catheter. Jejunal mucosal and serosal tissue PO2 were measured by means of Clark-type surface oxygen electrodes. Oxygen saturation and relative concentration of mucosal microvascular hemoglobin were measured by means of tissue reflectance spectrophotometry. In the fenoldopam group, systemic oxygen delivery (12.5 +/- 0.8 mL/kg/min at baseline) increased by 56% (p < .001) above baseline values. Mean arterial pressure remained unchanged. Fenoldopam produced a 51% increase in mucosal PO2 (23.8 +/- 2.8 torr [3.2 +/- 0.4 kPa] at baseline; p < .001) and a 31% increase in mucosal hemoglobin oxygen saturation (55.4 +/- 8.3% at baseline; p < .001), but not change in serosal PO2 (58 +/- 4.8 torr [7.7 +/- 0.6 kPa] at baseline). CONCLUSIONS: Fenoldopam improves tissue oxygenation of the porcine jejunum in a dose-related manner. This effect is limited to the inner mucosal layer. Dopamine-1-receptor agonists should be evaluated in patients presenting with signs of intestinal mucosal ischemia.

Animals↗
PubMed1995

[Bioprosthesis degeneration and reoperation in the aortic and mitral position].

In agreement with our experiences from our first study 15 patients (8 men, 7 women) underwent reoperation because of degeneration of bioprosthetic valves implanted in aortic or mitral position during the last 24 months. At reoperation 4 patients had a more complex cardiac procedure (double valve replacement, double valve replacement with bypass grafting, valve replacement with enlargement of the valvular area). There was no acute operation and only 1 patient was serious symptomatic preoperatively (NYHA IV). We revealed a mean implantation time of 126.4 months +/- 32.2 (median 130) for all bioprostheses without a significant difference in implant time regarding to aortic or mitral position. At reoperation bypass time (p = 0.001) and aortic clamp time (p = 0.011) was significantly longer compared to the first operation. There was no perioperative death, all patients are still alive and in good condition (8 of them NYHA I, 7 NYHA II). The early change of tissue degenerated bioprostheses can be carried out under elective conditions with improved postoperative outcome: mortality and morbidity remains acceptable low. In our group incremental risk factors for early mortality are severely affected patients with low functional status (NYHA IV) and acute operation. Preoperative coronary angiography remains essential for evaluation of concomitant coronary artery disease.

Adult↗
PubMed1995

[Standards in pediatric pacemaker therapy].

Despite differences between pediatric and adult pacing have narrowed, implantation procedures in children require special considerations. Patients are physically smaller, they often suffer from complex cardiac defects necessitating further open heart surgery procedures. As there are no pacemakers and only some electrodes designed specially for pediatric pacing, selection of appropriate systems is important. At this time we care for 18 patients with a mean age of 11.5 +/- 6.5 years (= 138.6 +/- 78.4 months, range 10 to 280 months). 50% of them received a permanent pacemaker because of surgically induced heart block, 33.3% because of congenital complete heart block and 16.7% because of sick sinus syndrome. Mean age at first pacemaker implantation was 57 +/- 42 months (Range 0 to 120 months). 72.2% of these children had their first pacing system implanted in the abdominal wall with an epicardial electrode, 27.8% had endovenous endocardial electrodes with subpectoral generator placement. 72.2% of our patients had already revisions of their pacing systems, mean longevity time of pulse generators were 36.8 +/- 21.8 months. Upgrading from single chamber pacing to physiological AV-sequential dual chamber pacing was performed at a mean age of 9.0 +/- 2.8 years (= 108.3 +/- 33.9 months, range 66 to 154 months). By reviewing our patient data we want to discuss present standards and guidelines of surgical pacemaker therapy in children and how to prevent potential complications.

Adolescent↗
PubMedDate not supplied

Epiaortic ultrasound and intraoperative transesophageal ecocardiography for the thoracic aorta atherosclerosis assessment in patient undergoing CABG. Surgical technique modification to avoid cerebral stroke.

BACKGROUND: Cerebral complication during coronary artery bypass surgery (CABG), still occurs in spite of cardiopulmonary bypass (CPB) technology advances. Our study sought to assess the role of epiaortic ultrasound (EAS) and intraoperative transesophagial ecocardiography (TEE) in detection of patients with atherosclerosis of the thoracic aorta and high risk for cerebral embolisation. Consequently our surgical strategies modification for a better cerebral protection. METHODS: Our lot study comprise 352 patients undergoing EAS and TEE, during CABG. EAS was performed before opening of the pericardium using a 7.5 MHz ultrasonic probe packed in a sterile bag. In the presence of moderate aortic atherosclerosis (maximum aortic wall thickness of 3 mm) primarily single aortic cross-clamping and choose of aortic cannulation place was carried out. In cases of severe aortic atheroma (maximum aortic wall thickness > 5 mm or mobile plaque), aortic no touch technique, off-pump were used. From 34 patients with severe ascending aortic atherosclerosis 22 of these patients (18 male, 4 female, age 72(57-79), Parsonet Score 11(0-8), Euroscore 8(2-13), McSPI Stroke Risk Index 6 (1-30%) were managed on "no touch technique", Off-pump. All patients received at least one left internal mammary artery (LIMA) in situ graft and additional extraanatomical bypass conduits: venous Y-graft from IMA (n = 14), arterial Y-graft from LIMA (n = 3), vein graft from axillary artery (n = 3), vein graft from the RIMA stump (n = 3). Median operative time was 240 (115-435) min. RESULTS: We found a mild aortic atherosclerosis in 151 patients (43%), moderate in 167 (47%) and severe in 34 patients (8.8%).. Operative mortality was 2/22 in a group with high risk index, from another cause than cerebral stroke. No cerebral stroke occurred. The rate of perioperative myocardial infarction (CKMB > 50U/l) was 5/22. Median stay in ICU, 54 hours (15-1245 hours). After a median follow up period of 8 months one death occurred from cerebral stroke and no myocardial infarction. CONCLUSION: Accurate detection of atheroma on ascending aorta and aortic arch by a combination between EAS and TEE and in special surgical technique modification using off-pump revascularization and extraanatomical bypass for the management of a heavily calcified aorta can result in a very low stroke rate despite a considerable stroke risk. The hospital mortality and morbidity can be lower than predicted by Euroscore and Parsonet Score.

Aged↗
PubMedDate not supplied

Management of profound hypothermia.

Profound hypothermia, defined as a core temperature of less than 28 degrees C, is a life-threatening situation associated with high mortality. Causes of severe hypothermia are prolonged exposure to cold air, water or snow. Initial basic life support and correct decisions to further therapeutic management are crucial for the patient's outcome.

Body Temperature Regulation↗