Louis-Philippe Fortier

Rationale for heating oxaliplatin for the intraperitoneal treatment of peritoneal carcinomatosis: a study of the effect of heat on intraperitoneal oxaliplatin using a murine model.

Objective:To study the effect of heat on the absorption of intraperitoneal (IP) oxaliplatin using a murine model. Background:Because of its efficiency in the systemic treatment of colorectal cancer, oxaliplatin is currently used in hyperthermic intraperitoneal chemotherapy (HIPEC) for peritoneal carcinomatosis. However, its properties when administered by the IP route have not been well characterized by preclinical studies. Methods:Under general anesthesia, 35 Sprague–Dawley rats were submitted to 3 different doses of IP oxaliplatin (460, 920, and 1840 mg/m2) at 3 different perfusion temperatures (37, 40, and 43°C) during 25 minutes. At the end of perfusion, samples in different compartments (peritoneum, portal blood, and systemic blood) were harvested and the concentrations of oxaliplatin were measured by high performance liquid chromatography. Results:As the dose of IP oxaliplatin was increased, higher concentrations were observed in every compartment. When the temperature of IP oxaliplatin was increased, it resulted in an increase of its peritoneal concentration (linear regression 0.38; 95% CI: 0.28–0.47) and in a decrease of its systemic blood (linear regression −1, 02; 95% CI: −1.45 to −0.60) and portal blood (linear regression −1.08; 95% CI: −1.70 to −0.47) concentrations. Conclusion:Proportionally to the dose administered, IP oxaliplatin leads to high concentration of drug in peritoneal tissues. Furthermore, heat enhances peritoneal tissue concentration of Oxaliplatin while reducing its systemic absorption. This last effect may possibly lead to decreased systemic toxicity. These observations support the use of oxaliplatin for HIPEC.

Massive gastrointestinal hemorrhage after transoesophageal echocardiography probe insertion

PurposeTo describe a case of a massive gastric bleeding following emergency coronary artery bypass surgery associated with transoesophageal echocardiographic (TEE) examination.Clinical featuresA 50-yr-old man was referred for an acute myocardial infarction and pulmonary edema (Killip class 3). Twelve hours after his myocardial infarction, he was still having chest pain despite aniv heparin infusion. Coronary angiography revealed severe three-vessel disease with multifocal stenosis of the left anterior descending, circumflex and total occlusion of the right coronary artery. The patient was transferred to the operating room for emergency coronary artery bypass graft surgery. After total systemic heparinization (3 mg·kg−1) was obtained for cardiopulmonary bypass, a multiplane TEE probe was inserted without difficulty to monitor myocardial contractility during weaning from CPB. During sternal closure, the TEE probe was removed and an orogastric tube was inserted with immediate drainage of 1,200 ml red blood. Endoscopic examination demonstrated a mucosal tear near the gastro-oesophageal junction and multiple erosions were seen in the oesophagus. These lesions were succesfully treated with submucosal epinephrine injections and the patient was discharged from the hospital eight days after surgery.ConclusionThis is a report of severe gastrointestinal hemorrhage following TEE examination in a fully heparinized patient. This incident suggest that, if the use of TEE is expected, the probe should preferably be inserted before the administration of heparin and the beginning of CPB.RésuméObjectifDécrire un cas de gastrorragie survenue après un pontage aortocoronarien et associée à un examen par échocardiographie transoesophagienne (ETO).Aspects cliniquesUn homme de 50 ans a été admis à l’hôpital pour un infarctus aigu du myocarde et un oedème pulmonaire (classification de Killip : 3). Douze heures après l’infarctus, il éprouvait toujours des douleurs thoraciques malgré une perfusion intraveineuse d’héparine. La coronarographie a montré une maladie tritronculaire sévère qui se manifestait par une sténose multifocale de l’artère interventriculaire antérieure, de l’artère auriculo-ventriculaire et l’occlusion totale de l’artère coronaire droite. Le patient a été transporté à la salle d’opération pour un pontage aortocoronarien d’urgence. Après que l’héparinisation générale totale (3 mg·kg−1) a été obtenue pour la circulation extracorporelle, une sonde d’ETO multiplan a été facilement introduite pour contrôler la contractilité du myocarde pendant le sevrage de la CEC. Pendant la fermeture stemale, on a retiré la sonde d’ETO et on a inséré un tube orogastrique pour un drainage immédiat de 1200 ml de sang rouge. Lexamen endoscopique a démontré une dilacération près de la jonction oeso-gastrique et de multiples érosions ont été visualisées dans l’oesophage. Ces lésions ont été traitées avec succès par des injections sous-muqueuses d’épinéphrine et le patient a quitté l’hôpital huit jours après la chirurgie.ConclusionNous avons rapporté le cas d’une hémorragie gastro-intestinale sévère survenu à la suite d’une ETO chez un patient complètement héparinisé. Cet incident permet de présumer que, dans le cas où on pense utiliser l’ETO, la sonde devrait, de préférence, être introduite avant l’administration d’héparine et le début de la CEC.

Magnetic interference of cardiac pacemakers from a surgical magnetic drape.

Sterile magnetic drapes are frequently used during surgery to hold metal instruments on the sterile field. Magnetic fields may potentially interfere with the function of cardiovascular implantable electronic devices such as pacemakers and implantable cardioverter defibrillators. In this study, we evaluated the potential magnetic interference of magnetic drapes on pacemaker function. A magnetic drape with 70 magnets was placed with its approximate center over the pacemaker of 50 patients during their visit to the cardiology clinic. In those pacemakers that demonstrated magnetic interference, the drape was pulled caudally in 3-cm increments until the interference ceased. If there was no interference, the drape was folded in 2 over the pacemaker. The number of magnets necessary to maintain magnetic interference with the pacemaker was also tested. Magnetic interference was observed in the pacemakers of 47 (94%) patients: 35 with the unfolded drape and another 12 with the folded drape. Patients whose pacemakers had interference with the unfolded drape weighed less (68±15 kg vs 81±19 kg; P = 0.016) than those who had no interference. In 54% of patients, magnetic interference ceased when the drape was pulled 3 cm caudally and at 15 cm, no pacemaker had magnetic interference. Magnetic drapes may cause magnetic interference with cardiac pacemakers, and this interference ceases at a caudal distance of 15 cm. Magnetic interference seems more likely in patients with lower body weight. Careful monitoring of the pulse and electrocardiogram for asynchronous pacing activity should be considered when magnetic drapes are used in patients with cardiovascular implantable electronic devices.

Same postoperative pain relief with morphine-fentanyl and morphine

Mireille Nolet, Department of Anesthesiology, Maisonneuve-Rosemont Hosp, Montreal, QC, Canada; Pierre Drolet, Department of Anesthesiology, Maisonneuve-Rosemont Hospital; Louis-Philippe Fortier, Department of Anesthesiology, Maisonneuve-Rosemont Hospital; D Audy, Department of Anesthesiology, Maisonneuve-Rosemont Hospital; B Petit, Department of Anesthesiology, Maisonneuve-Rosemont Hospital; F Donati, Department of Anesthesiology, Maisonneuve-Rosemont Hospital;