[Emergency operation for traumatic thoracic aortic rupture diagnosed by enhanced chest computed tomography; report of a case].

Thoracic aortic injury caused by blunt chest trauma is often fatal. Although aortography had been inevitable for thoracic surgery until recently, image of computed tomography (CT) is often superior to aortogram nowadays. We present a case of 64-yaer-old man with blunt chest trauma by traffic accident, who was successfully diagnosed and operated without invasive aortography. Thoracic aortic rupture was suspected by plain chest X-ray. His enhanced CT showed the localized leakage of contrast media near the arterial ligament of aortic arch. Because his condition was critically ill, operation was performed immediately without aortography. There found Y-shaped tear at the distal aortic arch, and was replaced with a prosthetic graft. Operation was performed under left heart bypass using heparin-coated circuit and centrifugal pump. We would stress that the enhanced chest CT is sufficiently diagnostic in thoracic aortic trauma like the present case.

[A successful treatment for myonephropathic metabolic syndrome after operation of acute aortic dissection (Stanford type A) with multiple organ ischemia].

A 60-year-old man had sudden chest pain and right lower extremity pain. A diagnosis of acute aortic dissection (Stanford type A) with right lower extremity ischemia was made. An emergency ascending aortic and total arch replacement, right axillo-femoral bypass, and coronary artery bypass grafting was performed for acute aortic dissection, acute right iliac arterial occlusion, and acute myocardial infarction. Myonephropathic metabolic syndrome (MNMS) occurred 2 days after operation. The serum creatine kinase value increased over 68,000 U/l, hemodiafiltration was started on the 2nd postoperative day (POD). The patient fell into anuric state and hemodiafiltration was performed 3 times a week. Urination was obtained over 1,000 ml/day from the 25th POD and hemodiafiltration was not necessary any more. We emphasize that prompt operation including revascularization of ischemic leg should be performed in acute aortic dissection with extremity ischemia and also prompt hemodiafiltration to improve the prognosis of these disastrous lesion.

[Electroencephalographic characteristics during maintenance and emergence from propofol-ketamine-fentanyl anesthesia].

Spectral edge frequency 90 (SEF 90) and relative power in four frequency bands (beta, alpha, theta, delta) of the processed electroencephalogram were recorded in 20 patients undergoing elective gynecological surgery under total intravenous anesthesia (propofol-ketamine-fentanyl) (group PKF, n = 10) or nitrous oxide-oxygen-isoflurane (group GOI, n = 10) anesthesia. During anesthesia, mean SEF 90 and relative beta power increased more significantly in group PKF than in group GOI. At emergence from anesthesia, SEF 90 was 21.8 Hz in group PKF and 20.5 Hz in group GOI. These results suggest that it is difficult to evaluate the depth of anesthesia using pEEG under PKF anesthesia.

[A new method of continuous propofol infusion for total intravenous anesthesia].

Total intravenous anesthesia (TIVA) is recommended to avoid air pollution. However, intermittent administration of anesthetic agents has a large disadvantage of delayed emergence time. We suggested continuous TIVA with propofol, ketamine, vecuronium and buprenorphine (PKBp), and reported that maintenance with continuous intravenous administration of propofol corresponding to the age associated with ketamine (240 micrograms.kg-1.h-1), vecuronium (80 micrograms.kg-1.h-1) and buprenorphine (0.4 microgram.kg-1.h-1) brought rapid emergence and that the last 1/6 of anesthetic time was the point to reduce propofol maintenance dose. In this study, we maintained anesthesia with continuous intravenous administration of propofol using twice step down method every one hour. We conclude that the reduction of propofol maintenance dose for every 1/6 in one hour produces fewer dropout cases.

[Continuous total intravenous anesthesia is recommended for wake-up test].

Total intravenous anesthesia (TIVA) has been recommended in view of avoiding air pollution. However, intermittent administration of anesthetic agents has a large disadvantage of delayed emergence time. We reported that continuous TIVA with propofol, ketamine, vecuronium and buprenorphine (PKBp) could bring rapid emergence time. An 8-year old female with spinal scoliosis underwent spinal instrumentation under continuous TIVA. Wake-up test was done twice during surgery smoothly after stopping infusion of anesthetic agents in the cocktail. We conclude that continuous TIVA is one of the most recommended anesthetic methods for wake-up test.

[A clinical dose finding study of propofol in continuous total intravenous anesthesia].

Total intravenous anesthesia (TIVA) is recommended in view of avoiding air pollution. However, intermittent administration of anesthetic agents has a disadvantage of delayed emergence time. We have suggested continuous TIVA with propofol, ketamine, vecuronium and buprenorphine (PKBp), and reported that the elder or the patients anesthetized for a long time show delayed emergence from continuous TIVA. In this study, after induction with propofol, ketamine, vecuronium and buprenorphine, the subjects were maintained with continuous intravenous administration of propofol corresponding to the age using twice step down method with ketamine (240 micrograms.kg-1.h-1), vecuronium (80 micrograms.kg-1.h-1) and buprenorphine (0.4 microgram.kg-1.h-1). Emergence was evaluated from the 2nd step down of propofol to awareness. There was a linear relationship between the emergence (2nd step down time of propofol to awareness) (Y) and the anesthetic time (X); Y = 0.175X + 3.00. We conclude that the last 1/6 (= 0.175) of anesthetic time is the point to reduce maintenance doses of propofol to achieve more rapid emergence.

[Economical benefit of continuous total intravenous anesthesia].

Total intravenous anesthesia (TIVA) has been recommended in view of avoiding air pollution. However, intermittent administration of anesthetic agents has a large disadvantage of delayed emergence. We reported that continuous TIVA with propofol, ketamine, vecuronium and buprenorphine (PKBp) could bring rapid emergence. In this study, we calculated and compared the cost of anesthesia in the subjects who had undergone general anesthesia either with continuous PKBp or nitrous oxide-oxygen-sevoflurane. In group PKBp subjects, after induction with propofol, ketamine, vecuronium and buprenorphine, anesthesia was maintained with continuous intravenous administration of propofol corresponding to the patient's age using twice step down method; ketamine (240 micrograms.kg-1.h-1), vecuronium (80 micrograms.kg-1.h-1) and buprenorphine (0.4 microgram.kg-1.h-1). Group GOS subjects, after the same induction method, received nitrous oxide, sevoflurane and vecuronium. Moreover, the group GOS subjects were divided to two groups; the high flow GOS (N2O:O2:sevoflurane = 4 l:2 l:30 ml) and the low flow GOS (N2O:O2:sevoflurane = 2 l:1 l:15 ml). Continuous PKBp group showed lower cost than the high flow GOS group. The PKBp group showed lower cost than the low flow GOS group except in patients weighing more than 100 kg. Furthermore, we calculated the cost of continuous PKBp anesthesia in Japan, U.S.A. and U.K. The U.S.A. cost of PKBp was higher than the Japanese and the U.K., because the cost of ketamine in U.S.A. is higher than in the other countries. Continuous PKBp is more economical than the high flow GOS, and continuous PKBp in Japan is more economical than in U.S.A.

[Early postoperative results of coronary revascularization with the radial artery: an analytical study of vascular diameter ratio of the graft and the coronary artery].

Between October 1996 and June 1988, radial artery grafts were used in 49 patients undergoing myocardial revascularization. There were three hospital deaths, none of them due to the use of radial artery. In 32 patients studied early, 33 of 34 radial artery grafts were patent (patency 97%), and 30 of 32 internal thoracic artery grafts (94%), 32 of 35 saphenous vein grafts (90%), 3 of 3 gastroepiploic artery grafts (100%) were patent respectively. The mean diameter ratio of graft and recipient coronary artery was 1.03 +/- 0.17 in radial artery, 0.92 +/- 0.16 in internal thoracic artery and 1.67 +/- 0.55 in saphenous vein graft. Our result suggest that the radial artery is an excellent conduit for myocardial revascularization, although a longer follow-up is mandatory.

[Continuous total intravenous anesthesia is useful for postoperative pain management].

We compared postoperative pain in two groups. All anesthetic agents were continuously administered intravenously in a continuous PKF (propofol 2-10 mg.kg-1.h-1, ketamine 240 micrograms.kg-1.h-1 and fentanyl 0.4 microgram.kg-1.h-1) group. In a control group, anesthesia was maintained by GOI (N2O-oxygen-isoflurane). Twenty-two patients scheduled for gynecological lower abdominal surgeries were divided into the continuous PKF group (n = 11) and the GOI group (n = 11). Epidural anesthesia was employed in both groups, using local anesthetic agents and fentanyl during surgeries and for 24 hrs postoperatively. To evaluate pain, VAS and Prince Henry Score on rest, cough and movement were taken 2 hrs and 5 hrs postoperatively, and in the morning and afternoon of the 1st as well as 2nd postoperative days. The continuous PKF group showed lower scores than the GOI group. It is a great advantage to use continuous PKF for postoperative pain management, and our data indicate that low dose ketamine may induce pre-emptive analgesia.

[Anesthetic management by continuous total intravenous anesthesia].

Total intravenous anesthesia (TIVA) is one of the most recommended methods of anesthesia for the prevention of air pollution. But the intermittent administration of anesthetic agents has a disadvantage of elongating emergence time. When inexperienced residents undertake TIVA with larger doses of drugs to stabilize vital signs, it takes long emergence time. Therefore, we suggested a continuous TIVA with propofol, ketamine and vecuronium in combination with butorphanol (PKBt) or buprenorphine (PKBp). In this study, we compared emergence times in the subjects, who underwent general anesthesia with PKBt and PKBp. After induction with propofol (2 mg.kg-1), ketamine (0.5 mg.kg-1), vecuronium (0.1 mg.kg-1) and agonist-antagonist opioids, subjects in each group were maintained with continuous intravenous injection of propofol (2-10 mg.kg-1.h-1), ketamine (240 micrograms.kg-1.h-1) and vecuronium (80 micrograms.kg-1.h-1) in combination with butorphanol (8 micrograms.kg-1.h-1) or buprenorphine (0.4 microgram.kg-1.h-1). The emergence times were designated as Op time (the end of operation to awareness), Pr time (the end of propofol to awareness), and B time (the end of butorphanol or buprenorphine to awareness). The emergence times of Op, Pr and B were not different between the groups. The elderly patients showed longer B time than the younger. The patients with long anesthetic time showed longer B time than the patients with short anesthesia. The patients with general anesthesia combined with epidural anesthesia showed longer B time than the patients with only general anesthesia. But there were no differences in Op time and Pr time. We conclude that the continuous TIVA is useful to reduce emergence time and prevent air pollution.

Characterization of nociceptin hyperalgesia and allodynia in conscious mice.

1. Intrathecal (i.t.) administration of nociceptin and high doses of morphine induced allodynia in response to innocuous tactile stimuli, and i.t. nociceptin evoked hyperalgesia in response to noxious thermal stimuli in conscious mice. Here we have characterized the nociceptin-induced allodynia and compared it with the morphine-induced allodynia and the nociceptin-evoked hyperalgesia. 2. Nociceptin-induced allodynia was evoked by the first stimulus 5 min after i.t. injection, reached a maximum at 10 min, and continued for a 50 min experimental period. Dose-dependency of the allodynia showed a bell-shaped pattern from 50 pg to 5 ng kg-1, and the maximum effect was observed at 2.5 ng kg-1. 3. Morphine-induced allodynia reached the maximum effect at 15 min and declined progressively until cessation by 40-50 min. The dose-response curve showed a bell-shaped pattern, similar to that induced by nociceptin, with a maximum effect at 0.5 mg kg-1, five orders of magnitude higher than that of nociceptin. 4. The allodynia evoked by nociceptin and morphine were dose-dependently blocked by glycine, D(-)-2-amino-5-phosphonovaleric acid (D-AP5, an N-methyl-D-aspartate (NMDA) receptor antagonist), gamma-D-glutamylaminomethyl sulphonic acid (GAMS, a non-NMDA receptor antagonist) and methylene blue (a soluble guanylate cyclase inhibitor), but were not affected by muscimol (a gamma-aminobutyric acidA (GABAA) receptor agonist) and baclofen (a GABAB receptor agonist). 5. Morphine did not inhibit forskolin-stimulated cyclicAMP formation in cultured cells expressing the nociceptin receptor. 6. Nociceptin-induced hyperalgesia was evoked 10-15 min after i.t. injection. Nociceptin produced a monophasic hyperalgesic action over a wide range of doses from 5 fg to 50 ng kg-1. The nociceptin-induced hyperalgesia was blocked by glycine only among the agents examined. 7. None of the pain responses evoked by nociceptin and morphine were blocked by naloxone. 8. These results demonstrate that, whereas the mechanisms of the nociceptin-induced allodynia and hyperalgesia are evidently distinct, they involve a common neurochemical event beginning with the disinhibition of the inhibitory glycinergic response. Morphine may induce allodynia through a pathway common to nociceptin, but the nociceptin receptor does not mediate the action of high doses of morphine.

[Surgical correction of an incomplete endocardial cushion defect in a 66-year-old male with the remarkable pulmonary hypertension].

A surgical case of a 66-year-old male with an endocardial cushion defect (ECD) is reported. He had preoperative pulmonary hypertension (80/25 mmHg, Pp/Ps 0.61), hypoxia (63.7 mmHg) and decreased creatinin clearance (45.7 ml/min). Respiratory condition was New York Heart Association's (NYHA's) grade III. Angiocardiography showed a typical gooseneck deformity associated with mitral and tricuspid valve regurgitations with the cleft (Seller's grade II and III). As surgical correction, direct suture of the cleft in an anterior leaflet with mitral annuloplasty, patch closure of the ostium primum defect with Xenomedical patch and tricuspid annuloplasty were performed. Postoperative data were restored to NYHA grade I. decreased pulmonary artery pressure (43/21 mmHg) and resistances (Pp/Ps 0.36). The only three surgical treatments of an incomplete ECD were reviewed in over 65-year-old patients in Japan included one perioperative death. Although we suggest it should be actively taken surgical repair even in elderly patients with pulmonary hypertension.

[Postoperative pain relief for a patient with elective mutism by patient controlled analgesia].

We previously reported that intrathecal (i.t.) administration of morphine reduced postoperative pain in pediatric patients after spinal instrumentation for scoliosis (Cotrel-Dubousset method), and the i.t. administration of morphine before incision produced better pain relief than that given after the surgical procedure. In this study, we evaluated postoperative pain relief in a patient with elective mutism who had been given i.t. morphine 0.15 mg before surgery. The patient was scheduled to undergo patient controlled analgesia (PCA) intravenously with morphine after surgery. The grade of postoperative pain and incidence of side effects were assessed at 1, 2, 6, 12, 24, and 48 h after the operation. The pain was rated by means of a verbal numeric rating scale (0-3) and a visual analog scale (VAS) (0-100mm). The used morphine volume shown on a PCA device was evaluated at scheduled times. No patient developed hemodynamic instability or respiratory depression during the monitoring period. We conclude that PCA can be useful for the patient with elective mutism.

Involvement of glutamate receptors in strychnine- and bicuculline-induced allodynia in conscious mice.

BACKGROUND: Glycine and gamma-aminobutyric acid (GABA) are inhibitory neurotransmitters that appear to be important in sensory processing in the spinal dorsal horn. Intrathecal administration of strychnine (strychnine-sensitive glycine receptor antagonist) or bicuculline (GABAA antagonist) was reported to induce allodynia. Although the strychnine-induced allodynia was shown to be mediated through the N-methyl-D-aspartate (NMDA)-type glutamate receptor, it is not clear whether the bicuculline-evoked-allodynia is mediated through the glutamate receptor system or how different the allodynia induced by strychnine and bicuculline are. METHODS: Male ddY mice weighing 20 +/- 2 g were used in this study. A 27-G stainless-steel needle attached to a microsyringe was inserted between the L5 and L6 vertebrae by a slight modification of the method of Hylden and Wilcox. Drugs in vehicle were injected slowly into the subarachnoid space to conscious mice at 22 +/- 2 degrees C. The volume of the intrathecal injection was 5 microliters. Studies on allodynia were carried out essentially according to the method of Yaksh and Harty. RESULTS: The intrathecal administration of strychnine or bicuculline in conscious mice resulted in allodynia elicited by nonnoxious brushing of the flanks. The maximum allodynia induced by strychnine was observed 5 min after intrathecal injection, but that induced by bicuculline was observed 10 min after intrathecal injection. Both responses gradually decreased over the experimental period of 50 min. The allodynia induced by strychnine was dose-dependently relieved by NMDA receptor antagonists (D-AP5, ketamine, and 7-C1-KYNA) and non-NMDA receptor antagonists (GAMS and CNQX) but not by metabotropic receptor antagonists (L-AP3 and L-AP4). On the other hand, allodynia induced by bicuculline was dose-dependently relieved by GAMS, L-AP3, and L-AP4, but not by D-AP5, ketamine, 7-C1-KYNA, and CNQX. Whereas the strychnine-evoked allodynia was dose-dependently relieved by the nitric oxide synthase inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME) and the soluble guanylate cyclase inhibitor methylene blue, the bicuculline-induced one was dose-dependently relieved by methylene blue but not by L-NAME. CONCLUSIONS: These results demonstrate that both strychnine- and bicuculline-evoked allodynia were mediated through pathways that include the glutamate receptor and nitric oxide systems but in a different manner. the current study suggests that GABA and glycine may modulate responses to an innocuous tactile stimulus as inhibitory neurotransmitters at presynaptic and postsynaptic sites in the spinal cord, respectively.

[Coronary artery bypass grafting for acute myocardial infarction].

Five hundred and fourteen cases with acute myocardial infarction were admitted to our hospital during the past 5 years, since April 1990. Among 343 cases who had emergency coronary angiography, 53 cases had coronary artery bypass grafting surgery within 2 weeks after the onset of acute myocardial infarction. Mean number of bypass grafts was 2.9 +/- 0.9/patient, and operative mortality was 25% (13/53). Clinical condition immediately before the surgery and surgical mortality was, shock state in 20 cases (mortality 50%), IABP dependent state in 23 cases (mortality 13%), post-infarction angina in 8 cases (mortality 0%). Mortality in 8 cases whose infarct-related artery was left main trunk was as high as 63%. Eight of 9 cases whose cardiac indices were below 2.01/min/m2 immediately after the surgery died of pump failure. On the contrary, only 2 of 37 cases whose post-operative cardiac indices were above 2.01/min/m2 died of non-cardiac reason. To improve the surgical results, we concluded that powerful mechanical support such as ventricular assist system should be applied to post-operative pump failure cases whose cardiac indices were below this limit despite the aid of IABP.

L-NAME, an inhibitor of nitric oxide synthase, blocks the established allodynia induced by intrathecal administration of prostaglandin E2.

We recently reported that intrathecal (i.t.) administration of prostaglandin E2 (PGE2) to conscious mice induced allodynia, a state of discomfort and pain evoked by innocuous tactile stimuli. In the present study, we examined the effect of the PGE receptor EP1 subtype antagonist ONO-NT-012, the N-methyl-D-aspartate (NMDA) receptor antagonist MK-801, and the NO synthase inhibitor N omega-nitro-L-arginine methyl ester (L-NAME) on the allodynia. The PGE2-induced allodynia was blocked by simultaneous i.t. injection of ONO-NT-012, MK-801, or L-NAME. However, 5 min after i.t. injection of PGE2, the allodynia was significantly blocked by i.t. L-NAME, but not by i.t. ONO-NT-012 or MK-801. These results demonstrate that the PGE2-induced allodynia, once developed, does not require the continued agonist occupancy of EP1 and NMDA glutamate receptor sites.

[Use of Finapres during warming for postoperative patients].

We used Finapres during rewarming after extracorporeal circulation in 16 patients who underwent cardiac surgery. In patients with passive rewarming there were no differences in blood pressure measured with a Finapres and that by an invasive monitor. On the other hand, in patients rewarmed with the aid of nitroglycerin, there were statistically significant differences between blood pressures measured with indirect and direct methods.

[Acute aortic dissection due to cross-clamp injury during coronary artery bypass grafting--a report of successfully repaired case].

A case with successfully repaired acute aortic dissection due to cross-clamp injury during coronary bypass surgery was reported. A 54-year-old man had usual coronary artery bypass surgery by using 3 saphenous vein grafts (4 distal anastomosis). Immediately after the completion of cardiopulmonary bypass, acute aortic dissection, which was caused by aortic cross-clamp, was noted. Cardiopulmonary bypass was resumed and the injured ascending aorta was replaced with prosthetic graft under profound hypothermia and circulatory arrest. An "Island flap" of the ascending aorta (3 x 4 cm in diameter), containing 3 proximal anastomotic positions of vein grafts, was excised from the aortic wall, and was re-implanted into the frontal wall of the aortic prosthesis. The patient well tolerated the operative procedure, and fully recovered from the serious condition after 6 days of IABP support and 11 days of inotropic support. He is doing quite well one year after the surgery. This case is believed to be the first reported one of such reconstructive method for acute aortic dissection during the coronary bypass surgery.