Spinal cord blood flow after ischemic preconditioning in a rat model of spinal cord ischemia.

Spinal cord blood flow after ischemic preconditioning is poorly characterized. This study is designed to evaluate spinal cord blood flow patterns in animals after acute ischemic preconditioning. Experiment 1: After a laminectomy and placement of a laser Doppler probe over the lumbar spinal cord to measure spinal cord blood flow, 16 male Sprague-Dawley rats were randomized into two groups: ischemic preconditioning (IPC, n = 8), and control (CTRL, n = 8).

Intrathecal morphine reduces infarct size in a rat model of ischemia-reperfusion injury.

Unlabelled: Systemically-administered morphine reduces infarct size in rat models of myocardial ischemia-reperfusion. We sought to determine whether much smaller doses of spinally-administered morphine offer a similar cardioprotective benefit. Barbiturate-anesthetized, open-chested, Wistar rats with chronic indwelling thoracic intrathecal catheters were instrumented for hemodynamic measurements and subjected to 30 min of coronary occlusion and 90 min of reperfusion.

Does vacuum-assisted venous drainage increase gaseous microemboli during cardiopulmonary bypass?

Background: Vacuum-assisted venous drainage enables adequate drainage through small-diameter cannulas but concerns are that it results in more gaseous microemboli delivered to the patient.

Methods: Five identical embolus detectors monitored the propagation of entrained air through a cardiopulmonary bypass (CPB) model. The ability of the CPB circuit to remove gaseous microemboli was studied with vacuum-assisted venous drainage and gravity siphon venous drainage using different pump speeds and rates of gaseous microemboli delivery.

Does local anesthetic stereoselectivity or structure predict myocardial depression in anesthetized canines?

Background And Objectives: It is unclear whether the susceptibility to myocardial depression from an accidental intravascular local anesthetic (LA) administration is associated with LA stereoselectivity or structure. By using direct left ventricular pressure monitoring and echocardiographic indices of contractile function in anesthetized, ventilated dogs, we compared the cardiac depressant effects of bupivacaine, ropivacaine, levobupivacaine, and lidocaine.

Methods: Open-chest dogs were randomized to receive escalating incremental infusions of the 4 local anesthetics until cardiovascular collapse.

How effective are cardiopulmonary bypass circuits at removing gaseous microemboli?

An association has been demonstrated between intravascular microemboli and organ injury during cardiopulmonary bypass (CPB). Air may be inadvertently introduced into the venous line during CPB resulting in the formation of gaseous microemboli (GME). We studied the ability of CPB circuits, from five different manufacturers, to remove GME originating from the introduction of air into the venous line.