Robert Blain

Off-pump revascularization of the circumflex artery: technical aspect and short-term results

BACKGROUND Beating heart surgery is a technique currently used for revascularization of the anterior and inferior territory. However, revascularization of the circumflex artery is more problematic. With a specific apparatus and surgical technique, we have extended the use of beating heart surgery to more than 90% of patients with multivessel disease, including those necessitating circumflex artery revascularization. METHODS Between October 1996 and November 1997, 140 patients underwent beating heart surgery by the same surgeon (R.C.). Among these patients, 111 required reconstruction of the circumflex artery territory and were followed up prospectively. They represent the cohort of patients presented in this study. There were 90 men and 21 women averaging 64+/-9.9 years of age. Mean left ventricular ejection fraction was 55%+/-13.7%, and a significant left main coronary artery disease was present in 27% of the patients. Five patients had prior coronary revascularization. RESULTS An average of 3.1+/-0.1 grafts/patient were performed. Complete revascularization was achieved in 95%. Only 1 patient needed conversion to cardiopulmonary bypass because of spontaneous ascending aortic dissection. Perioperative and postoperative bleeding were 446+/-245 mL and 644+/-442 mL, respectively. Homologous transfusions were required in 40% of the patients. Myocardial infarction occurred in 2.7% and operative mortality in 0.7% (1 patient). Average hospital stay was 6.6+/-3.1 days, and no patient exhibited early recurrence of angina. Early coronary angiograms (first 8 patients) demonstrated a 100% patency with 95% freedom from significant stenosis. CONCLUSIONS Complete coronary artery revascularization is feasible on the beating heart without the assistance of cardiopulmonary bypass with a low morbidity and mortality and excellent early angiographic results. Long-term follow-ups are needed to substantiate the potential long-term benefits of this technique.

End-tidal carbon dioxide tension and temperature changes after coronary artery bypass surgery

Variations in end-tidal carbon dioxide partial pressure (PetCO2) and temperature were measured for six hours following coronary artery bypass surgery in twenty patients. In the recovery room, the patients were mechanically ventilated with a tidal volume of 12 ml·kg-1. Arterial blood gases were drawn every two hours, and the respiratory frequency was adjusted to maintain arterial carbon dioxide pressure (PaCO2) in the range of 30– 45 mmHg. Naso-pharyngeal temperature was recorded every 30 minutes, andPetCO2 was measured continuously. The mean difference between temperature-corrected arterial and end-tidal CO2 pressure measurements was 3.2 mmHg (SD = 2.8; r = 0.963). This difference did not vary with time, temperature or PCO2. The largest temperature increases (mean 1.7°C/hour) occurred at a mean of 253 minutes after the end of surgery. End-tidal PCO2 increased markedly as temperature rose, in spite of a coincident increase in ventilation and then decreased as temperature stabilized. Large increases in CO2 production, caused by the metabolic demands during rewarming, most likely account for these changes. It is concluded that end-tidal CO2 recordings are reliable, and can help in maintaining normocarbia during the short but unstable period associated with rewarming following cardiac surgery.RésuméChez vingt malades ayant subi des pontages aorto-coronariens, nous avons mesuré les variations des pressions de gaz carbonique enfin d’expiration (PetCO2) et les changements de temperature au cours des six premieres heures post-operatoires. Ces malades étaient ventileés mécaniquement et leur volume courant était de 12 ml·kg-1. Les gaz du sang artériel étaient analysés aux deux heures et la fréquence respiratoire ajustée de façon à maintenir un PaCO2 entre 30 et 45 mmHg. La temperature naso-pharyngée était notée aux trente minutes et laPetCO2 mesurée de façon continue. Lorsque la PaCO2 est corrigée en fonction de la température, la différence moyenne entre cette PaCO2 et laPetCO2 est de 3.2 mmHg (SD = 2.8; r = 0.963). Cette différence n’est pas influencée par le temps, la température ni les valeurs de PCO2 . Vers la quatrième heure après la fin de la chirurgie, la température corporelle s’élève rapidement (en moyenne de 1.7° Clheure). LaPetCO2 s’accroît de façon marquée au moment de l’lévation de température, malgré une augmentation concomitante de la ventilation; puis laPETCO2 diminue lorsque la température corporelle se stabilise. Ces changements semblent être dus à une augmentation importante de la production de CO2, suite a des demandes métaboliques accrues au cours du réchauffement. Done, l’enregistrement continu du CO2 en fin d’expiration (PetCO2) est une méthode fiable qui peut aider à maintenir une normocarbie au cours de la période courte mais instable qui accompagne le réchauffement.

Innovative Approaches in the Perioperative Care of the Cardiac Surgical Patient in the Operating Room and Intensive Care Unit

Perioperative care for cardiac surgery is undergoing rapid evolution. Many of the changes involve the application of novel technologies to tackle common challenges in optimizing perioperative management. Herein, we illustrate recent advances in perioperative management by focusing on a number of novel components that we judge to be particularly important. These include: the introduction of brain and somatic oximetry; transesophageal echocardiographic hemodynamic monitoring and bedside focused ultrasound; ultrasound-guided vascular access; point-of-care coagulation surveillance; right ventricular pressure monitoring; novel inhaled treatment for right ventricular failure; new approaches for postoperative pain management; novel approaches in specialized care procedures to ensure quality control; and specific approaches to optimize the management for postoperative cardiac arrest. Herein, we discuss the reasons that each of these components are particularly important in improving perioperative care, describe how they can be addressed, and their impact in the care of patients who undergo cardiac surgery.

Safety of protamine sulfate administration in vasectomized men

The majority of vasectomized men develop antibodies against different sperm antigens, including protamine. Due to the fact that salmon protamine is used clinically for heparin reversal and that a cross-reactivity has been observed between human and salmon protamine, vasectomized men may be at risk for adverse reactions to protamine sulfate. In order to explore this possibility, serum samples were analyzed for the presence of anti-sperm and anti-protamine antibodies in 20 vasectomized and 20 non-vasectomized men (controls) about to undergo major heart surgery requiring heparin reversal. The patients were closely monitored for any possible reaction following the injection of protamine. Anti-sperm antibodies were detected in the serum of 15 of the vasectomized men whereas only two of the non-vasectomized subjects had this type of antibody. Twenty-five percent of the vasectomized men presented with anti-protamine antibodies; in the control group, none of the patients had developed this type of antibody. Following the administration of protamine sulfate, none of the patients in either group showed any adverse reaction to the drug. It is concluded that vasectomized men are not at increased risk towards adverse reactions following the injection of protamine sulfate.

Hemodynamic and pharmacodynamic comparison of doxacurium and high-dose vecuronium during coronary artery bypass surgery: a cost-benefit study

Doxacurium (DOX), a new nondepolarizing neuromuscular blocking drug (NMBD), was compared in a randomized, double-blind fashion to high-dose vecuronium (VEC) in 60 coronary artery bypass grafting (CABG) patients. A third group of 15 patients older than 70 years of age (DOX-70) was added to compare the effects of DOX to VEC in the older population. Endpoints of the study were hemodynamic stability, ease of ventilation and intubation, anesthesiologists satisfaction, drug interventions to correct hemodynamic instability, and total cost of the drug. Anesthesia was induced with fentanyl (30 micrograms/kg) along with the NMBD (DOX 80 micrograms/kg, VEC 400 micrograms/kg) over a 2-minute period. Following induction, heart rate (HR) and mean arterial pressure (MAP) were decreased (P < 0.01) in all groups. Tracheal intubation caused the HR to return to baseline in the DOX-70 group. There was no difference in central venous pressure, pulmonary artery occlusive pressure, cardiac index, systemic vascular resistance, and drug intervention for DOX and VEC. None of the patients had evidence of myocardial ischemia. There was a statistically significant but clinically irrelevant decrease in central venous pressure and systemic vascular resistance in the DOX-70 group. The durations of the induction and maintenance doses of DOX were similar in the younger and older patients. Although the intubating dose of VEC had a faster onset of action, this had no effect on the ease of ventilation, conditions for tracheal intubation, and overall anesthesiologist satisfaction. The total cost for each NMBD was not different.(ABSTRACT TRUNCATED AT 250 WORDS)