Search PubMed⌕ Search

Biomedical subjects

André Denault

Publications and source records attributed to André Denault.

18 recordsLinked to original sources
PubMed2006

Canadian guidelines for training in adult perioperative transesophageal echocardiography. Recommendations of the Cardiovascular Section of the Canadian Anesthesiologists' Society and the Canadian Society of Echocardiography.

PURPOSE: To establish Canadian guidelines for training in adult perioperative transesophageal echocardiography (TEE). METHODS: Guidelines were established by the Canadian Perioperative Echocardiography Group with the support of the cardiovascular section of the Canadian Anesthesiologists' Society (CAS) in conjunction with the Canadian Society of Echocardiography. Guidelines for training in echocardiography by the American Society of Echocardiography, the American College of Cardiology and the Society of Cardiovascular Anesthesiologists were reviewed, modified and expanded to produce the 2003 Quebec expert consensus for training in perioperative echocardiography. The Quebec expert consensus and the 2005 Guidelines for the provision of echocardiography in Canada formed the basis of the Canadian training guidelines in adult perioperative TEE. RESULTS: Basic, advanced and director levels of expertise were identified. The total number of echocardiographic examinations to achieve each level of expertise remains unchanged from the 2002 American Society of Echocardiography-Society of Cardiovascular Anesthesiologists guidelines. The increased proportion of examinations personally performed at basic and advanced levels, and the level of autonomy at the basic level suggested by the Quebec expert consensus are retained. These examinations can be performed in a perioperative setting and are not limited to intraoperative TEE. Training "on the job", the role of the perioperative transesophageal echocardiography examination, requirements for maintenance of competence, and duration of training are also discussed for each level of training. The components of a TEE report and comprehensive TEE examination are also outlined. CONCLUSION: The Canadian guidelines for training in adult perioperative TEE reflect the unique Canadian practice profile in perioperative TEE and address the training requirements to obtain expertise in this field.

Adult↗
PubMed2006

Randomized controlled trial of pericardial blood processing with a cell-saving device on neurologic markers in elderly patients undergoing coronary artery bypass graft surgery.

BACKGROUND: Processing of pericardial shed blood with a cell-saving device was claimed to prevent lipid microembolization and to protect from neurocognitive dysfunction after cardiopulmonary bypass. The present study tested the hypothesis that processing of pericardial shed blood with a cell-saving device during cardiopulmonary bypass would significantly decrease serum levels of protein S100B, and improve brain oxygen saturation and neurologic outcome, all markers of brain injury in elderly patients. METHODS: Forty patients, 65 years of age and older, undergoing coronary artery bypass graft with cardiopulmonary bypass, were prospectively randomly assigned to processing of pericardial shed blood with a cell-saving device or to conventional use of a standard closed venous reservoir where cardiotomy blood was collected and reinfused through the arterial circuit (control group). Serum in S100B was measured 30 minutes, 4 hours, 24 hours, and 48 hours after surgery. Near-infrared spectroscopy monitoring was performed during the procedure and the National Institutes of Health stroke scale was measured before surgery and at the time of discharge of the hospital. RESULTS: Patients in the cell-saving device group averaged 72 +/- 3 years of age and underwent 3.1 +/- 0.7 coronary artery grafts with a mean of 62 +/- 20 minutes of cardiopulmonary bypass time. Patients in the control group averaged 75 +/- 4 years of age (p = 0.03) and underwent 3.3 +/- 0.6 coronary artery grafts (p = 0.49) with a mean of 75 +/- 25 minutes of cardiopulmonary bypass time (p = 0.12). The quantity of blood administered from the cell-saving device averaged 281 +/- 162 mL per patient. Serum protein S100B levels averaged 0.06 +/- 0.03 before surgery and 0.51 +/- 0.23 microg/L 30 minutes after surgery in the cell-saving device patients compared with 0.076 +/- 0.04 before surgery (p = 0.32) and 1.48 +/- 0.66 (p < 0.0001) in the control patients. The near-infrared spectroscopy baseline mean value of left and right cortical region was 58% +/- 12% and 55% +/- 7% in the cell-saving device group versus 59% +/- 7% and 53% +/- 6% in the control group (p = 0.67 and 0.36), and no difference occurred over time in each group. The National Institutes of Health stroke score before and after surgery was similar in the two groups. There was one cerebrovascular complication in the control group (1 of 20, 5%) after surgery. CONCLUSIONS: The difference between the two groups occurred 30 minutes after surgery, at which time serum levels of protein S100B were significantly higher in the control group compared with cell-saving device patients. Although use of the cell-saving device was not associated with higher brain oxygen saturation nor changes in the National Institutes of Health stroke score, it is associated with lesser release of nonspecific markers of brain injury in elderly patients.

Aged↗
PubMed2006

Canadian guidelines for training in adult perioperative transesophageal echocardiography. Recommendations of the Cardiovascular Section of the Canadian Anesthesiologists' Society and the Canadian Society of Echocardiography.

PURPOSE: To establish Canadian guidelines for training in adult perioperative transesophageal echocardiography (TEE). METHODS: Guidelines were established by the Canadian Perioperative Echocardiography Group with the support of the cardiovascular section of the Canadian Anesthesiologists' Society in conjunction with the Canadian Society of Echocardiography. Guidelines for training in echocardiography by the American Society of Echocardiography, the American College of Cardiology and the Society of Cardiovascular Anesthesiologists were reviewed, modified and expanded to produce the 2003 Quebec expert consensus for training in perioperative echocardiography. The Quebec expert consensus and the 2005 guidelines for the provision of echocardiography in Canada formed the basis of the Canadian training guidelines in adult perioperative TEE. RESULTS: Basic, advanced and director levels of expertise were identified. The total number of echocardiographic examinations to achieve each level of expertise remains unchanged from the 2002 American Society of Echocardiography and the Society of Cardiovascular Anesthesiologists guidelines. The increased proportion of examinations personally performed at basic and advanced levels, as well as the level of autonomy at the basic level suggested by the Quebec expert consensus are retained. These examinations may be performed in a perioperative setting and are not limited to intraoperative TEE. Training 'on-the-job', the role of the perioperative TEE examination, the requirements for maintenance of competence and the duration of training are also discussed for each level of training. The components of a TEE report and comprehensive TEE examination are also outlined. CONCLUSION: The Canadian guidelines for training in adult perioperative TEE reflect the unique Canadian practice profile in perioperative TEE and address the training requirements to obtain expertise in this field.

Adult↗
PubMed2005

A pilot study: the Noninvasive Surface Cooling Thermoregulatory System for Mild Hypothermia Induction in Acute Myocardial Infarction (the NICAMI Study).

BACKGROUND: Hypothermia reduces metabolic demands, limits reperfusion injury, and helps salvage the injured myocardium during ST-elevation myocardial infarction (STEMI). The aim of this study was to assess early induction of noninvasive mild hypothermia in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention (PCI). METHODS: This was a safety and feasibility study of the Medivance Arctic Sun noninvasive thermoregulatory system (Medivance Inc, Louisville, Colo), used as adjunctive therapy in patients with first-time STEMI. Cooling was initiated by circulating chilled water through the Arctic Sun Energy Transfer Pads placed on the patient before primary PCI. Target temperature was 34.5 degrees C, maintained during 3 hours. Shivering was controlled with intravenous meperidine, and meperidine-related nausea was prevented with intravenous ondansetron. RESULTS: Nine patients underwent successful noninvasive surface cooling. All patients were Killip class I with a mean age of 62 years (8/9 males). Successful primary stenting was performed in all patients with glycoprotein inhibitors administered in 6 of 9 cases. Mean cooling time from induction to target temperature was 79 minutes (49 minutes in the last 4 enrolled cases). Mean total cooling duration was 267 minutes. Mean peak troponin T was 5.81 microg/L. Final TIMI flow grade 3 and final TIMI perfusion grade 3 were achieved in 9 of 9 patients and in 3 of 9 patients, respectively. Mean infarct size (by Myoview single photon emission computed tomography scans) was 23%. No hemodynamic or arrhythmic instability were documented. CONCLUSION: Mild hypothermia can be safely induced with noninvasive surface cooling in patients with STEMI undergoing primary PCI, allowing earlier myocardial protection before mechanical reperfusion therapy.

Angioplasty, Balloon, Coronary↗
PubMed2005

Pulmonary edema and cardiac dysfunction following subarachnoid hemorrhage.

BACKGROUND: Pulmonary edema (PE) can occur in the early or late period following subarachnoid hemorrhage (SAH). The incidence of each type of PE is unknown and the association with ventricular dysfunction, both systolic and diastolic, has not been described. METHODS: Retrospective chart review of 178 consecutive patients with SAH surgically treated over a three-year period. Patients with pulmonary edema diagnosed by a radiologist were included. Early onset SAH was defined as occurring within 12 hours. Cardiac function at the time of the PE was analyzed using hemodynamic and echocardiographic criteria of systolic and diastolic dysfunction. Pulmonary edema was observed in 42 patients (28.8%) and was more often delayed (89.4%). Evidence of cardiac involvement during PE varied between 40 to 100%. RESULTS AND CONCLUSIONS: Pulmonary edema occurs in 28.8% of patients after SAH, and is most commonly delayed. Cardiac dysfunction, both systolic and diastolic, is commonly observed during SAH and could contribute to the genesis of PE after SAH.

Adult↗
PubMed2004

Mixed venous blood gas sampling is not influenced by the speed of withdrawal in cardiac surgery patients.

OBJECTIVE: To determine whether mixed venous blood gas sampling obtained by pulmonary artery catheter (PAC) is influenced by the speed of withdrawal. DESIGN: Prospective, observational study. SETTING: Surgical intensive care unit at a university hospital. SUBJECTS: Twenty-five patients in the early postoperative period of cardiac surgery. MEASUREMENTS AND MAIN RESULTS: After verification of the adequate position of the PAC, measurements of mixed venous blood gas oxygen saturation, oxygen partial pressure (PO(2)), carbon dioxide partial pressure (PCO(2)), pH and bicarbonates were obtained at two different rates of withdrawal. A slow sampling was taken at a mean speed of 3 ml/min and a fast sampling at 18 ml/min for each patient. The mean difference in venous oxygen saturation between slow and fast samplings was -0.18+/-1.3%, venous PO(2): -0.2+/-1.3 mmHg, venous PCO(2): 0.1+/-0.9 mmHg, venous pH: 0+/-0.03, venous bicarbonates: 0.03+/-0.5 mmol/l. CONCLUSION: Using the Bland & Altman method, we showed a satisfactory agreement between slow and fast mixed venous blood gas sampling techniques when measuring PO(2), oxygen saturation, PCO(2), pH and bicarbonates though a PAC.

Aged↗
PubMed2004

Poor correlation between hemodynamic and echocardiographic indexes of left ventricular performance in the operating room and intensive care unit.

OBJECTIVES: To compare hemodynamic and echocardiographic indexes of left ventricular performance. DESIGN: Retrospective database analysis of four clinical trials. SETTING: University hospital. PATIENTS: Cardiac surgery patients. INTERVENTION: Left ventricular performance was evaluated using left ventricular stroke work index (LVSWI) calculated from the pulmonary artery catheter and both fractional area change and regional wall motion score index (RWMSI) measured from transesophageal echocardiography. Measures of left ventricular performance were obtained before and after bypass (group 1, n = 30), during acute increase and decrease in preload (group 2, n = 14), after administration of inhaled prostacyclin or placebo in patients with pulmonary hypertension (group 3, n = 20), and in hemodynamically unstable patients in the intensive care unit at admission and at 2 and 4 hrs (group 4, n = 20). MAIN RESULTS: A total of 186 simultaneous LVSWI, fractional area change, and RWMSI were analyzed and compared. Patients with RWMSI <1.3 had a LVSWI of 23.4 +/- 10.3 g.m.m compared with 18.4 +/- 7.2 g.m.m in those with RWMSI >1.3 (p =.0349). Subdividing fractional area change into three different groups (> or =50%, 25% to 49%, and < or =24%), the corresponding values of LVSWI were 22.3 +/- 9.7 g.m.m, 22.2 +/- 10.8 g.m.m, and 17.7 +/- 5.5 g.m.m, respectively (p =.5114). Correlations between LVSWI and RWMSI changes ranged from -0.28 to 0.16 (p values from.31 to.94). Correlations between LVSWI and fractional area change changes ranged from -0.62 to 0.22 (p values from.07 to.95). CONCLUSION: There is a significant discrepancy and limited relationship between the hemodynamic and echocardiographic evaluation of left ventricular performance.

Analysis of Variance↗
PubMed2003

Transesophageal echocardiography monitoring in the intensive care department: the management of hemodynamic instability secondary to thoracic tamponade after single lung transplantation.

A 65-year-old woman with pulmonary fibrosis had hemodynamic instability develop after single lung transplantation. Transesophageal echocardiography was useful in determining the cause of hemodynamic instability, which was secondary to thoracic tamponade. Furthermore, transesophageal echocardiography monitoring was important in the decision to initiate extracorporeal membrane oxygenation to evaluate adequate positioning of the cannula and in the extracorporeal membrane oxygenation weaning process.

Aged↗
PubMed2003

Inhaled epoprostenol (prostacyclin) and pulmonary hypertension before cardiac surgery.

OBJECTIVE: Pulmonary hypertension is commonly found in patients undergoing valvular surgery and can be worsened by cardiopulmonary bypass. Inhaled epoprostenol (prostacyclin) has been used for the treatment of pulmonary hypertension, but its effects compared with those of placebo on hemodynamics, oxygenation, echocardiographic examination, and platelet function have not been studied during cardiac surgery. METHODS: Twenty patients with pulmonary hypertension undergoing cardiac surgery were randomized in a double-blind study to receive inhaled epoprostenol (60 microg) or placebo. The inhalation occurred after induction of anesthesia and before surgical incision. The effects on left and right systolic and diastolic cardiac functions evaluated by means of pulmonary artery catheterization and transesophageal echocardiography, as well as oxygenation and platelet aggregation, were studied. RESULTS: Inhalation of epoprostenol significantly reduced indexed right ventricular stroke work from 10.7 +/- 4.57 g. m. m(-2) to 7.8 +/- 3.94 g. m. m(-2) (P =.003) and systolic pulmonary artery pressure from 48.4 +/- 18 mm Hg to 38.9 +/- 11.9 mm Hg (P =.002). The effect was correlated with the severity of pulmonary hypertension (r = 0.76, P =.01) and was no longer apparent after 25 minutes. There was no significant effect on systemic arterial pressures, left ventricular function, arterial oxygenation, platelet aggregation, and surgical blood loss. CONCLUSION: Inhaled epoprostenol reduces pulmonary pressure and improves right ventricular stroke work in patients with pulmonary hypertension undergoing cardiac surgery. A dose of 60 microg is hemodynamically safe, and its effect is completely reversed after 25 minutes. We did not observe any evidence of platelet dysfunction or an increase in surgical bleeding after administration of inhaled epoprostenol.

Administration, Inhalation↗
PubMed2002

Mechanisms of hemodynamic changes during off-pump coronary artery bypass surgery.

PURPOSE: To describe the mechanisms of hemodynamic changes during off-pump coronary artery bypass graft surgery (OP-CABG). SOURCE: Pertinent medical literature in the English and French languages was identified through a Medline computerized literature search and a manual search of selected articles, using off-pump coronary artery surgery, beating heart surgery, hemodynamic, and transesophageal echocardiography as key words. Human and animal studies were included. PRINCIPAL FINDING: Hemodynamic variations in OP-CABG may be due to mobilization and stabilization of the heart, or myocardial ischemia occurring during coronary occlusion. Suction type and compression type stabilizers produce hemodynamic effects through different mechanisms. Heart dislocation (90 degrees anterior displacement) and compression of the right ventricle to a greater extent than the left ventricle are responsible for hemodynamic alterations when using suction type stabilizers. Compression of the left ventricular outflow tract and abnormal diastolic expansion secondary to direct deformation of the left ventricular geometry are proposed mechanisms for hemodynamic derangements with compression type stabilizer. Coronary occlusion during the anastomosis can have additional effects on left ventricular function, depending on the status of collateral flow. The value and limitations of electrocardiographic (ECG), hemodynamic and echocardiographic monitoring modalities during OP-CABG are reviewed. CONCLUSIONS: In summary, hemodynamic changes which can either be secondary to the stabilization technique or to transient ischemia represent an important diagnostic challenge during off-bypass procedures. The mechanism can vary according to the stabilization system. Current monitoring such as ECG and hemodynamic monitoring are used but remain limited in establishing the cause of hemodynamic instability. Transesophageal echocardiography is used in selected patients to diagnose the etiology of hemodynamic instability and can direct therapy, particularly in those with severe myocardial systolic and diastolic dysfunction, mild to moderate mitral regurgitation, or for patients who are unstable during the procedure.

Animals↗
PubMed2002

A comprehensive strategy to avoid transesophageal echocardiography probe damage.

PURPOSE: To describe the factors predisposing to transesophageal echocardiography (TEE) probe damage and to propose a strategy aimed at preventing damage to the TEE probe. Description of equipment and procedures: Damage to the TEE probe can occur anywhere and anytime during use in the operating room (OR) or when the probe is not in use in the OR, such as in the cleaning room, during storage or during transport of the probe. The components of the strategy used in our institution to avoid probe damage are: 1) storage of the probe in a dedicated holder in the OR when it is not in use, 2) use of a lexan box in the OR to protect the probe connector, 3) use of a custom-made holder when the probe is inserted in the patient, 4) use of a dedicated holder for soiled TEE probe storage in the cleaning room and for subsequent probe storage. CONCLUSION: We describe a comprehensive strategy designed to decrease TEE probe damage and the associated expenses. Further studies will be required to determine the effectiveness of the proposed measures.

Echocardiography, Transesophageal↗
PubMed2002

Hemodynamic changes during off-pump CABG surgery.

OBJECTIVES: The purpose of this study was to assess the patients' hemodynamics during off-pump coronary artery bypass graft (OPCABG) surgery. METHODS: Continuous monitoring of the mean systemic arterial pressure (SAP), mean pulmonary arterial pressure (PAP), mixed venous oxygen saturation (SvO(2)) and cardiac output index (COI) was done on 55 patients undergoing complete OPCAB revascularization. Hemodynamic changes were recorded at the completion of the anastomosis before releasing coronary snaring and stabilization and compared to baseline. RESULTS: The mean age of the patients was 66.4+/-9.2 years, and on average 3.3+/-0.8 grafts per patient were performed. The average SAP drop after manipulations was -8.3+/-16.9 mmHg for the left anterior descending artery (LAD), -13.5+/-19.6 mmHg for the diagonal artery (DG), -14.6+/-13 mmHg for the optuse marginal artery (OM), and -14.2+/-13.5 mmHg for the right coronary artery. This was significant for all territories (P<0.01). The PAP significantly increased in all territories except OM (LAD: 3.7+/-6.3 mmHg, DG: 4.3+/-8.6 mmHg, OM: 1.1+/-7.2 mmHg, posterior descending artery: 2.7+/-5.6 mmHg; P<0.05). Variations in COI were significant in all territories (P<0.01) but more significantly in LAD and DG territories (-15+/-3% and -13+/-9%, respectively). The SvO(2) variations were <10% for all territories and reached only borderline significance (P=0.05) in all territories except OM. All these hemodynamic changes were well tolerated by all patients. CONCLUSIONS: Manipulation of the beating heart during OPCABG surgery brings significant fluctuations in the patients' hemodynamics. Mean PAP increase and COI drop were more significant during manipulation of the anterior territories suggesting a more severe diastolic restrictive disease during anterior wall manipulation.

Aged↗
PubMed2002

The hemodynamically unstable patient in the intensive care unit: hemodynamic vs. transesophageal echocardiographic monitoring.

OBJECTIVE: Transesophageal echocardiography is a diagnostic and monitoring modality. The objectives of our study were to compare the diagnoses obtained with continuous transesophageal echocardiography and hemodynamic monitoring in the intensive care unit, to determine interobserver variability of diagnosis obtained with both modalities, and to evaluate its impact. DESIGN: Prospective cohort study. SETTING: Surgical intensive care unit. PATIENTS: Consecutive hemodynamically unstable patients after cardiac surgery. INTERVENTIONS: At admission, unstable patients were monitored during 4 hrs with transesophageal echocardiography and standard hemodynamic monitoring. The critical care physician evaluated the patients based on all information except the transesophageal echocardiography at 0, 2, and 4 hrs and formulated a hypothesis on the most likely cause of hemodynamic instability. Transesophageal echocardiography information was provided after each evaluation. To evaluate interobserver variability, all the hemodynamic and echocardiographic information was gathered, randomized, and evaluated by five clinicians for the hemodynamic data and five echocardiographers for the transesophageal echocardiography data. The evaluators were blinded to all other information. Kappa statistics were used to evaluate agreement. Impact of transesophageal echocardiography was assessed retrospectively by using the Deutsch scale. RESULTS: Twenty patients qualified for the study. The agreement between the hemodynamic and echocardiographic diagnosis showed a kappa at admission, 2 hrs, and 4 hrs of 0.33, 0.47, and 0.28. The interobserver agreement for the initial diagnosis (p =.014) and between all evaluators (p <.001) was significantly higher in the echocardiographic compared with the hemodynamic group. The transesophageal echocardiographic information was considered retrospectively to be essential in 34% and valuable in 34% of cases. CONCLUSIONS: These observations support the belief that transesophageal echocardiographic monitoring in the intensive care unit is associated with higher interobserver agreement in diagnosing and excluding significant causes of hemodynamic instability for postoperative cardiac surgical patients.

Adult↗