Biomedical subjects

Norimasa Seo

Publications and source records attributed to Norimasa Seo.

At least 37 records · Page 2Linked to original sources

PubMed2005

[Critical incidents during regional anesthesia in Japanese Society of Anesthesiologists-Certified Training Hospitals: an analysis of responses to the annual survey conducted between 1999 and 2002 by the Japanese Society of Anesthesiologists].

BACKGROUND: Recently, a national survey in France including 35,439 patients who had received spinal anesthesia showed that the incidences of cardiac arrest and mortality associated with spinal anesthesia were 2.5 and 0.8 per 10,000 anesthetics, respectively. In this study, we investigated these values using data obtained from annual surveys conducted by the Japanese Society of Anesthesiologist (JSA). METHODS: Since 1994, JSA has conducted annual surveys concerning critical incidents in the operating theater by sending confidential questionnaires to JSA-certified training hospitals, then collecting and analyzing the responses. We investigated critical incidents associated with regional anesthesia using data from annual surveys between 1999 and 2002. The questionnaire was identical in each survey conducted during these years. The total number of anesthetics available for this analysis was 3,855,384, of which spinal anesthesia, combined spinal-epidural anesthesia and epidural anesthesia were performed in 409,338, 146,282, and 69,001 patients, respectively. In patients receiving regional anesthesia, 628 critical incidents including 108 cardiac arrests, and 45 subsequent deaths were reported. The causes of critical incidents were classified as follows: totally attributable to anesthetic management, due mainly to intraoperative pathological events, preoperative complications, and surgical management. IP consists of coronary ischemia including coronary vasospasm not suspected preoperatively, arrhythmias including severe bradycardia, pulmonary thromboembolism, and other conditions. Mortality was determined by postoperative day 7. Statistical analysis was performed by chi-square test and Mann-Whitney test. A p value less than 0.05 was considered significant. RESULTS: The incidences of cardiac arrest and mortality due to all etiologies were 1.69 and 0.76 with spinal anesthesia, 1.78 and 0.68 with combined spinal-epidural anesthesia, and 1.88 and 0.58/10,000 anesthetics with epidural anesthesia, respectively. The incidences of cardiac arrest and mortality due to anesthetic management were 0.54 and 0.02 with spinal anesthesia, 0.55 and 0.00 with combined spinal-epidural anesthesia, and 0.72 and 0.14/10,000 anesthetics with epidural anesthesia, respectively. These values did not significantly differ among regional anesthesia. Death attributable to anesthetic management was reported in 2 patients: both patients were classified as ASA-PS 3 E, and developed cardiac arrest; one due to inadvertent high spinal anesthesia with spinal anesthesia, and the other due to local anesthetic intoxication with epidural anesthesia. Anesthetic management and intraoperative pathological events comprised 33 and 43% of cardiac arrests, respectively. The distribution of causes of death was as follows: anesthetic management, 5%; intraoperative pathological events, 34%; preoperative complications, 35%; surgical management, 26%. Among the causes of anesthetic management-induced critical incidents, inadvertent high spinal anesthesia was the leading cause of cardiac arrest in spinal and combined spinalepidural anesthesia: 90% of arrests occurred in patients with ASA-PS 1+2; 88% in patients below 65 years of age; 45 and 25% in patients undergoing hip or lower extremities surgery, and cesarean section, respectively. Among the causes of intraoperative pathological event-induced critical incidents, pulmonary thromboembolism was the leading cause of cardiac arrest in spinal and combined spinal-epidural anesthesia: 59% of arrests occurred in patients with ASA-PS 1+2; 81% in patients above 66 years of age; 91% in patients undergoing hip or lower extremity surgery. CONCLUSIONS: The incidence of cardiac arrest and mortality associated with spinal anesthesia in Japan was shown to be in the same order as in France by analyzing a larger population. In patients with good ASA-PS, critical incidents occurred more often under regional anesthesia than under general anesthesia. Inadvertent high spinal anesthesia should be carefully avoided. We should also pay much attention to subclinical deep vein thrombosis in patients who were scheduled for hip or lower extremity surgery, and tourniquet- or bone cement-associated pulmonary embolism in these patients.

Anesthesia↗

PubMed2005

[Incidence and characteristics of perioperative pulmonary thromboembolism in Japan in 2003].

BACKGROUND: Pulmonary thromboembolism (PTE) is increasingly recognized as a significant perioperative complication in Japan. A recent study reported that the incidence was 0.32 patients per 10,000 people per year in Japan. The aim of this investigation is to elucidate the incidence and characteristics of perioperative pulmonary thromboembolism in Japan. METHODS: A questionnaire was mailed to 844 institutions registered under the Japanese Society of Anesthesiologists (JSA). The survey details included age, sex, type of surgery, and risk factors of the cases operated in 2003. RESULTS: Among the 844 institutions, 504 (59.7%) responded effectively. There were 440 cases of perioperative PTE in 230 institutions (45.6% of the institutions responded). The incidence of perioperative PTE was 4.76 per 10,000 cases. Massive PTE or cardiac arrest at the onset occurred in 60 cases (13.7%). Among these patients, 178 (40.5%) were obese, 162 (36.8%) had malignant diseases, and 111 (25.2%) were bed-ridden (> 4 days). The types of surgery that resulted in PTE with high frequency were "limbs and/or hip joint surgery" (9.0 per cases), "thoracic surgery with laparotomy" (7.6 per 10,000 cases), and "abdominal surgery" (6.6 per 10,000 cases). Eighty-three patients died from perioperative PTE; out of these, 9 (10.8%) died during operation, 23 (27.7%) died within 3 days after the operation, and 51 (61.4%) died 4 days after the operation. Despite having risk factors, 80 patients (33. 9%) either received unrecommended measures or did not receive any preventive measures for PTE. CONCLUSIONS: The incidence of perioperative PTE is not low in Japan and is 13 times higher than the rate observed in the general population. The use of thromboprophylaxis should be considered in patients with risk factors.

Adolescent↗

PubMed2005

[Posterior interosseous nerve palsy in a man in a lateral position for laparoscopic adrenalectomy--a case report].

A 51-year-old man with aldosteronism underwent laparoscopic left adrenalectomy. Anesthesia was induced with fentanyl 0.1 mg, propofol 140 mg and vecuronium 7 mg. Following endotracheal intubation, he was placed in a right lateral position with extension of his left side, and fixed with the Magic Bed. Canulation of the right radial artery was smoothly performed. Anesthesia was maintained with sevoflurane and thoracic epidural anesthesia (mepivacaine and ropivacaine). The operation lasted for 270 minutes and was uneventful. A few hours after surgery, he complained of inability to extend his right fingers without any sensory loss, and the local oppressive pain on his right forearm. Neurological examination revealed a posterior interosseous palsy. Symptoms improved gradually and disappeared completely in two months with the administration of vitamin B12 and physical therapy. Postoperative reproduction of the positioning of this case disclosed that the edge of the Magic Bed might potentially compress the posterior interosseous nerve at the point where the nerve is bifurcated from the radial nerve and travels within the supinator muscle going into the muscle again. This case indicated that we must be careful of nerve injuries due to devices used to maintain the patient in lateral position.

Adrenal Gland Neoplasms↗

PubMed2005

[Critical events in the operating room among 1,440,776 patients with ASA PS 1 for elective surgery].

BACKGROUND: The Japanese Society of Anesthesiologists (JSA) survey of critical incidents in the operating room has shown that preoperative complications are the leading causes of critical incidents, and affect the occurrence, severity and outcome of critical incidents which are due to causes other than preoperative complications. Causes of critical events in the operating room were examind in patients for elective surgery with American Society of Anesthesiologists physical status (ASA PS) 1. METHODS: JSA has conducted annual surveys of critical incidents in the operating room by sending and collecting confidential questionnaires to all JSA Certified Training Hospitals. From 1999 to 2002, 3,855,384 anesthesia patients were registered. Among these, 1,440,776 patients with ASA PS 1 for elective surgery were analyzed. The causes of critical incidents were classified as follows: totally attributable to anesthetic management (AM), mainly to intraoperative pathological events (IP), to preoperative complications (PC), and to surgical management (SM). IP consists of coronary ischemia mainly due to coronary vasospasm, arrhythmias, pulmonary embolism, and other conditions. RESULTS: The incidences of cardiac arrest, critical incidents other than cardiac arrest and subsequent death were 9.86, 59.41 and 3.12 per 100,000 anesthesia cases, respectively. IP and SM were responsible for 36.6% and 34.5% of cardiac arrest, respectively. AM and SM were responsible for 46.7% and 26.8% of critical incidents other than cardiac arrest, respectively. SM, IP and AM were responsible for 66.7%, 22.2% and 4.4% of subsequent deaths (within 7 postoperative days), respectively. Coronary ischemia and pulmonary embolism were the main causes of death due to IP. The incidences of cardiac arrest and death totally attributable to AM were 1.87 and 0.14 per 100,000 anesthesia cases, respectively. Medication problems were responsible for 48.1% of arrests, while airway/ventilation problems were for 57.2% of critical incidents other than arrest. Human factors (SM combined with AM) were responsible for 53.5%, 73.5%, and 71.1% of cardiac arrest, critical incidents other than arrest and death, respectively. CONCLUSIONS: Even in elective patients with good physical status, non-lethal incidents were not rare, and lethal incidents were also reported. We should pay significant attention to the following findings, and take some measures to overcome these problems especially related to human factors. Firstly, SM badly harmed some operative patients. Secondly, coronary vasospasm and pulmonary embolism were the main causes of death due to IP. Thirdly, drug administration and airway/ventilation management were the major causes of critical incidents totally attributable to AM. Human factors were responsible for 70.6% of critical incidents and 71.1% of deaths.

Anesthesia↗

PubMed2005

[The effect of colored syringes and a colored sheet on the incidence of syringe swaps during anesthetic management].

BACKGROUND: Syringe swap is an important problem in anesthetic care, causing harm to patients. We examined the effect of colored syringe and a colored sheet on the incidence of syringe swaps during anesthetic management. METHODS: We determined the color code. The blue-syringe contains local anesthetics; yellow-syringe, sympathomimetic drugs; and white-syringe with a red label fixed opposite the scale, muscle relaxants. The colored sheet displays the photographs of the syringe with drug name, dose and volume. The colored syringe and colored sheet were supplied for use from February 2004. We compared the incidence of syringe swaps during the period from February 2004 to January 2005 with that from February 2003 to January 2004. RESULTS: Although five syringe swaps were recorded from February 2003 to January 2004, in 5901 procedures, we encountered no syringe swaps from February 2004 to January 2005, in 6078 procedures. The colored syringe and colored sheet significantly decreased the incidence of syringe swaps during anesthetic management (P <0.05). CONCLUSIONS: The use of the sheet together with colored syringes can prevent syringe swaps during anesthesia.

Anesthesiology↗

PubMed2005

[Combined spinal epidural anesthesia for emergency cesarean section].

BACKGROUND: We performed a retrospective analysis to evaluate the usefulness of combined spinal epidural anesthesia (CSEA) in emergency cesarean section compared with conventional spinal anesthesia. METHODS: A retrospective chart analysis of patients who had undergone emergency cesarean section over a 7 year period was performed. We extracted at random 150 patients planned by spinal anesthesia, and 150 patients planned by separate-needle CSEA. Patient's data were gathered and analyzed according to the anesthetic technique used. RESULTS: There were no significant differences between the two groups in age, weight, and BMI. Although the time to incision and the time to delivery were significantly faster in spinal anesthesia group than in CSEA group, there was no significant difference in Apgar score between the groups. Moreover, failure of anesthesia and post-dural puncture headache were higher in spinal group than in CSEA group. CONCLUSIONS: CSEA is useful as anesthesia for an emergency cesarean section.

Adult↗

PubMed2005

[Ropivacaine-induced grand mal convulsion after obturator nerve block].

We describe a patient to whom ropivacaine 150 mg had been administered during obturator nerve blockade and developed grand mal convulsions because of inadvertent i.v. injection. Venous blood samples were taken 15, 32 and 52 min after the convulsion. The measured total plasma concentrations of ropivacaine were 4.5, 3.5 and 2.9 microg x ml(-1) respectively. The peak plasma concentration at the time of the inadvertent i.v. injection was estimated to be 6.6 microg x ml(-1). The patient recovered uneventfully.

Adult↗

PubMed2005

[Outsourcing of anesthesia support system].

BACKGROUND: Recently, the deficiency in anesthesiologist's man power became a social problem in Japan. Therefore, we tried outsourcing of anesthesia support system. METHODS: The questionnaire was sent to anesthesiologists after an anesthesia support system had started. RESULTS: All anesthesiologists answered reduction in the burden of work. CONCLUSIONS: Anesthesia support system outsourcing is effective in reducing the workload of anesthesiologists.

Anesthesiology↗

PubMed2004

Changes in plasma total and ionized magnesium concentrations and factors affecting magnesium concentrations during cardiac surgery.

The purpose of this study was to measure blood total and ionized magnesium concentrations ([TMg] and [Mg(2+)], respectively) and to investigate factors that might be affecting their changes during cardiac surgery using hypothermic cardiopulmonary bypass. Eight patients were examined. All the patients received diuretics and predeposited autologous blood during surgery. No drugs containing Mg(2+) were administered. Nine blood samples and eight urine samples were collected from the pre-induction period to the end of surgery. Hematocrit, [TMg], [Mg(2+)], plasma concentrations of calcium ([Ca(2+)]), creatinine, parathyroid hormone (PTH), urinary concentrations of TMg, and creatinine were measured, and the fractional excretion of Mg (FEMg) was calculated. Both [TMg] and [Mg(2+)] decreased significantly in the prebypass period and remained significantly depressed thereafter. The ionized fraction of magnesium ([Mg(2+)]/[TMg]) was decreased during the postbypass period. Hematocrit decreased significantly from the prebypass period, and FEMg increased significantly after aortic cross-clamping. In conclusion, hemodilution and renal loss were main causes of hypomagnesemia, and citrate in predeposited autologous blood may contribute to the decrease in [Mg(2+)]/[TMg] in the postbypass period. These results suggest that magnesium supplementation under close monitoring of [Mg(2+)] should be required during cardiac surgery.

Adult↗

PubMed2004

[Postintubation granuloma of the larynx].

A 50-year-old woman underwent tonsillectomy under general anesthesia. She developed progressive hoarseness two month after the tonsillectomy, and a large granuloma of the larynx was found. Surgical removal of the granuloma was performed by laryngo-microsurgery. We should keep in mind that postintubation granuloma of the larynx might develop after tracheal intubation, and careful airway manipulation is needed to avoid this potential complication.

Anesthesia, General↗

PubMed2004

[Annual mortality and morbidity in operating rooms during 2002 and summary of morbidity and mortality between 1999 and 2002 in Japan: a brief review].

The Japanese Society of Anesthesiologists (JSA) conducts an annual survey of life-threatening events in operating rooms (OR) in JSA Certified Training Hospitals (JSACTH) by sending and collecting confidential questionnaires. Etiologies of the incidents were divided into four categories: those totally attributable to anesthetic management (AM), those resulting from preoperative complications (PC), those resulting from intraoperative pathological events (IP) and those related to surgical procedures (SP). IP resulted from coronary ischemia not suspected preoperatively, arrhythmias, pulmonary embolism, and other conditions. Outcomes were judged on the 7th post-operative day. In the year 2002, questionnaires were sent to 844 JSACTHs, and a total of 1,461,020 cases of anesthesia were documented from 773 JSACTHs. Of these, 1,277,045 cases of anesthesia from 712 JSACTHs were available for analysis. Seven hundred thirty nine cardiac arrests (5.79 per 10,000 anesthetics) and 806 deaths (6.31 per 10,000 anesthetics) due to life-threatening events in the OR were reported. The incidence of cardiac arrest and mortality totally attributable to AM was 0.38 and 0.11 per 10,000 anesthetics. These values tended to decrease after 1994, except the mortality totally attributable to AM, which were almost at constant level during recent years. The summary of the study between 1999 and 2002 was as follows. Among 3,855,384 anesthetics, 2,443 cardiac arrests (6.34 per 10,000 anesthetics) and 2,638 deaths (6.85 per 10,000 anesthetics) due to life-threatening events in the OR were reported. PC, SP, IP and AM were responsible for 64.7, 23.9, 9.4, and 1.5% of deaths, respectively. The major cause of PC related deaths was preoperative hemorrhagic shock, followed by cardiovascular diseases such as myocardial ischemia and congestive heart failure. Excessive surgical bleeding comprised 70.2% of SP-related deaths. The major causes of IP-related death were myocardial ischemia, pulmonary embolism, and severe arrhythmias. The incidence of cardiac arrest and death totally attributable to AM was 0.47 and 0.10/10,000 anesthetics, respectively. Among patients with ASA-PS 1(E) and 2(E), AM-related deaths occurred at a rate of 0.04/10,000 anesthetics. Half of AM-induced deaths were caused by airway or ventilatory problems. Other causes of AM-related death were medication accidents and infusion/transfusion accidents. Considerable effort is required to reduce intraoperative life-threatening events caused by human error, hemorrhage, and cardiovascular diseases.

Anesthesiology↗

PubMed2004

[Hospital no-smoking policy could increase smoking cessation rate among preoperative patients].

BACKGROUND: Although it is well known that a no-smoking policy can reduce smoking rate among hospital employees, the effect of this policy on patients' smoking behavior has not been examined. METHODS: Starting on the world no-tobacco day in 2001, the Sakai Municipal Hospital changed partial no-smoking policy into complete no-smoking policy. In this study, we examined the effect of this policy change on patients' smoking status during preoperative period. At preoperative visit, we asked a patient a change of smoking status during preoperative period. The change of patients' smoking status was compared between before and after coming into effect of no-smoking policy. RESULTS: Smoking rates at first visit to out-patient clinic of each surgical department before and after coming into effect of no-smoking policy were 35.6%(36/101) and 41.8%(28/67), respectively (P=0.317). Among these smokers, smoking cessation rates at preoperative visit before and after coming into effect of no-smoking policy were 44.4%(16/36) and 75.0%(21/28), respectively (P=0.014). CONCLUSIONS: The hospital no-smoking policy has a strong effect on improvement of patients' smoking behavior during preoperative period.

Health Promotion↗

PubMed2004

[Incidence and characteristics of perioperative pulmonary thromboembolism in Japan].

BACKGROUND: Perioperative pulmonary thromboembolism (preoperative PTE) is widely recognized as one of the life-threatening perioperative complications in Japan. However, incidence of perioperative PTE is not well surveyed. The Japanese Society of Anesthesiologist (JSA) mailed the questionnaire about incidence of perioperative PTE and its characteristics to the institutions registered in JSA. METHODS: The questionnaire was mailed to 844 institutions. The items of the survey included age, sex, type of surgery and risk factors of the cases performed in 2002. Data were analyzed using chi-square test and Fisher's test, and P < 0.05 was taken as significant. RESULTS: Four-hundred sixty-seven out of 844 institutions responded (55.3%) effectively. There were 369 cases of perioperative PTE in 208 institutions (44.5% of the institutions responded). The incidence of perioperative PTE was 4.4 per ten thousand cases. Massive PTE or cardiac arrest at the onset occurred in 57 cases (15.4%). Out of these patients, 117 patients (31.7%) had obesity, and bed-ridden rest (> 4 days) patients and cancer patients were each 105 (28.5%). Sixty-six patients died from perioperative PTE, out of which 5 patients (7.5%) died during operation, 31 patients (47.0%) died within 7 days after the operation, and 30 patients (45.5%) died 8 days after the operation. The commonest type of surgery among mortality cases was abdominal surgery (20 cases: 30.3%), and the commonest risk factor was being bedridden (34.5 cases: 51.5%). The patients who had developed PTE during surgery counted 64, among whom the major type of operation was lower limb/pelvic surgery (36 cases: 56.3%). Major risk factors were being bed-ridden in 25 cases (39.1%) and lower limb/pelvic fracture in 25 cases (39.1%). Despite having dangerous risk factors, 128 patients (57.7%) received the measures not recommended or did not receive any preventive measure for PTE. CONCLUSIONS: This survey revealed that the incidence of perioperative PTE in Japan is considerable. On the ground that most PTE could be prevented, it is suggested that by employing preventive measures for PTE, the incidence of perioperative PTE will decrease.

Adolescent↗

PubMed2004

[Critical incidents due to drug administration error in the operating room: an analysis of 4,291,925 anesthetics over a 4 year period].

BACKGROUND: Wrong drugs, overdose of drugs, and incorrect administration route remain unsolved problems in anesthetic practice. We determined the incidence and outcome of drug administration error in the operating room of Japanese Society of Anesthesiologists Certified Training Hospitals. METHODS: Data were obtained from annual surveys conducted by Japanese Society of Anesthesiologists between 1999 and 2002. There were 4,291,925 cases of anesthetic delivery for this analysis. RESULTS: Incidence of critical incidents due to drug administration error was 18.27/100,000 anesthetics. Cardiac arrest occurred in 2.21 patients per 100,000 anesthetics. Causes of these critical incidents were as follows: overdose or selection error involving non-anesthetic drugs, 42.1%; overdose of anesthetics, 28.7%; inadvertent high spinal anesthesia, 17.9%; local anesthetic intoxication, 6.4%; ampule or syringe swap, 4.3%; blood mismatch, 0.6%. Incidence of death following these incidents was 0.44/100,000. Causes of death were as follows: overdose or selection error involving non-anesthetic drugs, 47.4%; overdose of anesthetics, 26.3%; inadvertent high spinal anesthesia, 15.8%; local anesthetic intoxication, 5.3%. Ampule or syringe swap did not lead to any fatalities. Death following inadvertent high spinal anesthesia and local anesthetic intoxication was reported only in patients who had developed cardiac arrest. It should be noted that 88 percent of ampule or syringe swap occurred in patients with American Society of Anesthesiologists-Physical Status 1 or 2, who did not seem to require complex anesthetic management. CONCLUSIONS: We should increase awareness that drug administration is generally performed with limited objective monitoring, although "To error is human". Increased vigilance is required to avoid drug administration error in the operating room. Additional anesthesia resident education, adequate supervision, and improved organization are necessary. Bar-coding technology might be useful in preventing drug administration error.

Anesthetics↗

PubMed2004

[The workshop of cardiopulmonary resuscitation for medical doctors in Jichi Medical Hospital].

The Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care (ECC) established in 2000 (Guidelines 2000) are the standard for cardiopulmonary resuscitation (CPR) all over the world. Written guidelines based on Basic Life Support (BLS) and Advanced Cardiac Life Support (ACLS) are widely available throughout Japan and are studied by physicians but ACLS training courses have been made available only recently. In 2003, our hospital formed a committee to address standards of patient safety and one of the recommendations of the committee was the attendance of standardized BLS by health care workers and of ACLS by physicians. In May, 2003 a total of 447 physicians from our hospital participated in a workshop on BLS which provided lectures, demonstrations and a written examination. After completion of this workshop, it has been concluded that standardization in the area of resuscitation is mandatory, and efforts to disseminate this workshop to health care practitioners are to be undertaken.

Cardiopulmonary Resuscitation↗

PubMed2004

[Evaluation of 100 anesthetic incidents].

BACKGROUND: The anesthetic incident-reporting scheme in the department of anesthesia, Jichi Medical School Hospital, has been running for 3 years and 100 incidents have now been reported. METHODS: An 'anesthetic incident' was defined as any incident related to anesthesia which either caused harm, or if uncorrected might have caused harm, to a patient. RESULTS: There were 26 problems involving drugs, 18 airway and respiratory problems, 15 dental damages, 11 cardiovascular problems, 8 problems related epidural anesthesia, and 22 others. CONCLUSIONS: The scheme has successfully highlighted weaknesses of the department.

Anesthesia↗

PubMed2004

[Surgical volume and mortality due to intraoperative critical incidents at Japanese Society of Anesthesiologists certified training hospitals: an analysis of the annual survey in 2002].

BACKGROUND: We have previously showed that surgical volume affects mortality due to intraoperative critical incidents among patients undergoing cardiac surgery, the surgery with the highest risk, using data obtained by the annual survey in 2001 conducted by the Japanese Society of Anesthesiologists (JSA). In this study, we investigated whether surgical volume affects mortality due to intraoperative critical incidents independent of the surgical site. METHODS: We investigated this relationship using data obtained from the 2002 annual survey conducted by the Subcommittee on Surveillance of Anesthesia-related Critical Incidents, JSA. Between January 1, 2002 and December 31, 2002, 1,987,988 patients were registered from 704 training hospitals certified by the JSA. Intraoperative critical incidents occurred in 2,844 patients. Of these, 804 patients died within 7 postoperative days. The overall mortality was 4.61 per 10,000 anesthetics. Hospitals were divided into 5 groups according to their annual surgical cases: Group A, fewer than 1,000 (62 hospitals); Group B, 1,000-1,999 (204 hospitals); Group C, 2,000-3,999 (288 hospitals); Group D, 4,000-5,999 (110 hospitals); Group E, more than 6,000 (40 hospitals). Hospitals were also divided into 2 groups according to mortality: Group 1, under 20.00 per 10,000 anesthetics (672 hospitals); Group 2, equal to or higher than 20.00 per 10,000 anesthetics (32 hospitals). Total number of deaths in Group 2 was 158. Mortality was expressed as the mean (95% confidence interval). Statistical analysis was performed using chi-square test and Fisher test. A p value of <0.05 was considered significant. RESULTS: The mortality rates in Groups A-E were 14.89 (8.48-21.3), 3.86 (3.05-4.67), 3.88 (3.19-4.57), 4.04 (3.20-4.88), and 3.12 (2.19-4.05) per 10,000 anesthetics, respectively. Average surgical cases and mortality in Group 1 were 2,789 (2,775-3,002) and 3.24 (2.90-3.58), respectively, while those in Group 2 were 1,672 (1,243-2,101) and 22.18 (30.58-45.94), respectively. If all patients in Group 2 (n=53,509) had been treated in the hospitals of Group 1, 139-143 deaths might have been avoided. CONCLUSIONS: Surgical volume was shown to affect mortality independent of the surgical site. Hospitals with low surgical volume should pay significant attention to improving surgical outcomes. These results also suggest that centralization or regionalization should be discussed from the perspective of socio-economical problems as well as patient safety.

Anesthesia↗

PubMed2003

Establishment of Alb-DsRed2 transgenic rat for liver regeneration research.

Because serum albumin is specifically produced by mature hepatocytes, detection system of albumin producing cells could be a valuable tool to visualize liver regeneration or development. We have developed here an albumin enhancer/promoter-driven Alb-DsRed2 Tg rat that expresses DsRed2, having liver-specific reporter gene expression of red fluorescent protein. To study the transdifferentiation of bone marrow cells (BMCs) into albumin producing cells, BMCs from the Alb-DsRed2 Tg rat were injected into rats having acute liver damage caused by 2-acetylaminofluorene plus carbon tetrachloride and chronic liver damage by repeated administration of CCl(4). DsRed2-positive cells were generated in the recipient liver after BMC injection. The number of transdifferentiated DsRed2-positive cells in chronic liver injury model was increased comparing with that in acute injury model. We propose that the Alb-DsRed2 Tg rat is well suited to studying in vivo liver regeneration.

Animals↗