Effects of epidural anesthesia with 0.2% and 1% ropivacaine on predicted propofol concentrations and bispectral index values at three clinical end points.

STUDY OBJECTIVE: To compare the effects of 0.2% epidural ropivacaine and those of 1% epidural ropivacaine on predicted propofol concentrations and bispectral index scores (BISs) at three clinical end points. DESIGN: Randomized double-blind study. SETTING: University hospital. PATIENTS: Thirty-five (35) ASA physical status I and II patients scheduled for elective surgery of the lower abdomen. INTERVENTIONS: Patients were randomly divided into 2 groups to receive epidurally 8 mL of 0.2% or 1% ropivacaine followed by the same solution at a rate of 6 mL/h. MEASUREMENTS: Twenty minutes after starting ropivacaine, a target-controlled infusion of propofol was started to provide a predicted blood concentration of 3 microg/mL; it increased by 0.5 microg/mL every 60 seconds until all 3 clinical end points were reached, as follows: P1, when patients lost consciousness; P2, when patients failed to show pupillary dilation and skin vasomotor reflex to transcutaneous electric stimulation applied to the upper level of loss of cold sensation; and P3, when patients failed to show pupillary dilation and skin vasomotor reflex to transcutaneous electric stimulation applied to C5. MAIN RESULTS: The effective concentration 50 values for both predicted blood and effect-site propofol concentrations were significantly larger in the 0.2% group than in the 1% group at all end points. The BIS at every end point was significantly smaller in the 0.2% group than in the 1% group. CONCLUSIONS: During combined epidural-propofol anesthesia, unconsciousness and lack of response to noxious stimulation occurred at lower predicted concentrations with 1% epidural ropivacaine than with 0.2% epidural ropivacaine. The results also suggest that the BIS may not be a good indicator when propofol anesthesia is combined with epidural anesthesia.

[A case of severe coronary artery spasm associated with anaphylactic reaction caused by protamine administration].

A 65-year-old man with mitral regurgitation and atrial fibrillation underwent mitral valve plasty and Maze's operation. Cardiopulmonary bypass (CPB) was finished uneventfully. But after protamine administration, severe systemic hypotension occurred suddenly with electrocardiographic ST-segment elevation and wide QRS intervals. We thought that this reaction had been caused by coronary spasm and not by anaphylactic reaction because he was without typical anaphylactic manifestations such as general rash and bronchospasm. We administered epinephrine, methylprednisolone, heparin for restarting CPB, and used IABP support to assist systemic circulation. We again tried to administer protamine to neutralize the anticoagulative effect of heparin when his vital sign had recovered, but the same reaction occurred immediately with small amounts of protamine. The second CPB was necessary for some time. This case suggests that coronary artery spasm associated with anaphylactic reaction was induced by administration of protamine. It is known that intravenous protamine administration sometimes causes adverse events. As in this case, we should consider the possibility of severe coronary spasm associated with anaphylactoid reaction even if other symptoms of anaphylactic reactions such as cutaneous manifestation and bronchospasm are not present.

Breath-holding spells in somatoform disorder.

Breath-holding spells (BHS) are commonly seen in childhood. However, there are no case reports of BHS occurring in adolescents or young adults. We report two young adult cases and discuss the pathogensis, both physically and psychologically. BHS occurred for 1-2 minutes after hyperventilation accompanied by cyanosis in both cases. Oxygen saturation was markedly decreased. Each patient had shown distress and a regressed state psychologically. These cyanotic BHS occurred after hyperventilation, and we considered that a complex interplay of hyperventilation followed by expiratory apnea increased intrathoracic pressure and respiratory spasm. Breath-holding spells can occur beyond childhood.

[Surgical stress in perioperative period of combined off-pump coronary artery bypass grafting and abdominal aortic aneurysm repair].

OBJECTIVES: It is still controversial whether we should choose simultaneous operation or two-staged operation for patients who need both coronary artery bypass grafting (CABG) and abdominal aortic aneurysm (AAA) repair. Some reports suggest that combined CABG without cardiopulmonary bypass and AAA repair is less invasive than those with cardiopulmonary bypass. We estimated surgical stress of combined off pump CABG and AAA repair (CABG + AAA) in perioperative period compared with simple AAA repair retrospectively. METHODS: Seven patients (mean 60 years) underwent simultaneous operation of off pump CABG and AAA repair in our institution. We gathered data associated with circulatory, respiratory, renal function, recovery, and so on. We also examined postoperative complication and mortality. RESULTS: All parameters, except operation time and amount of catecholamine used, were not significantly different between the two groups. There were no operative mortality and only a slight morbidity in CABG + AAA. CONCLUSIONS: Our findings suggest that careful circulatory management with adequate transfusion and catecholamine use under precise monitoring is necessary during operation, but recovery after surgery, complication, and mortality in this combined operation are almost equivalent to those of simple AAA repair. We suggest that combined operation of CABG and AAA repair can be performed effectively.

[Suddenly developing low output syndrome during acute thoracic aortic dissection surgery in a patient with progressive systemic sclerosis].

A 70-year-old man with progressive systemic sclerosis (PSS) suddenly developed low output syndrome (LOS) after weaning from cardiopulmonary bypass during acute thoracic aortic dissection and died in an early postoperative stage because of multiple organ failure. PSS was kept in a relatively good condition before onset of his surgical disease, but his Raynaud's phenomenon was much worse and inflammation findings were very severe before his operation. We suspected that PSS might have been involved in LOS in this case. PSS has many cardiac complications, for example spasm or organic changes of coronary artery, cardiac fibrosis, arrhythmia, secondary cardiac failure of pulmonary hypertension, pericardial inflammation, and so on, but we speculate that LOS might be caused by peripheral vessel disturbance. LOS occurs easily in chronic hypovolemic states and abnormal response of peripheral vessels due to PSS. We advise more careful anesthetic and circulatory management especially in invasive operation in PSS patients.