A report of 14,195 applications of anesthetics to oral and maxillofacial surgery at one teaching dental hospital (1971-2000) centering around airway problems.

STUDY OBJECTIVES: To examine the validity of our methods of anesthesia, i.e., awake intubation and assisted manual ventilation, in coping with the anesthetic problems particular to oral and maxillofacial surgery (OMF surgery). DESIGN: Prospective study. SETTING: Operating room and ward of a dental teaching hospital. PATIENTS: 14,195 patients undergoing OMF surgery during the period from January 1971 to March 2000. MEASUREMENTS AND MAIN RESULTS: The kinds of anesthetic difficulties centering around airway problems and their frequency in OMF surgery were determined. In 2,401 patients (16.9%), awake intubation was employed because of definite or possible airway problems. No untoward effects due to awake intubation were noted. Volatile anesthetics were used with nitrous oxide (N2O) in 13,959 patients (98.3%), and their spontaneous respiration were assisted manually for the purpose of early detection of airway troubles such as accidental extubation, dislocation, kinking, and/or damage to the endotracheal tubes. Few accidents or complications were noted in relation to airway issues, and neither cardiac arrest nor death was experienced in these 14,195 patients. CONCLUSIONS: Based on a sufficient number of anesthetic applications, awake intubation and assisted manual ventilation were proved to be useful in coping with the anesthetic difficulties particular to OMF surgery.

Histological evaluation of allograft bone after acetabular revision arthroplasty: report of two cases.

We recently had the opportunity to take histological sections from two patients who underwent acetabular reconstruction in which allograft and ME Müller acetabular roof reinforcement rings were used. In one patient (case 1), histological sections of the chipped allograft were taken on two separate occasions from the same area, at 7 months, and at 3 years and 11 months after the bone graft. The histology of the chipped allograft showed necrosis at 7 months, but almost normal morphology of trabecular bone formation at 3 years and 11 months after the bone graft. In the other patient (case 2) histological sections of the block allograft and chipped allograft were taken at 1 year and 8 months after the bone graft. The block allograft showed only a small amount of admixture of newly formed bone with the necrotic bone, while the chipped allograft showed a large amount of newly formed bone, with only a small amount of necrotic bone remaining. Therefore, we principally use chipped allograft for acetabular reconstruction, in order to achieve early and complete graft incorporation. If a block allograft is used in a weight-bearing area, it should be protected from excessive load by using an acetabular reinforcement device.

[Characterization of spontaneous liver metastatic model of BALB/c retroperitoneal sarcoma (LMFS) injected in footpad and antitumor effects of HCFU].

A new spontaneous liver metastasis model from LMFS tumor, a retroperitoneal sarcoma of BALB/c mouse origin, was reported. After a subcutaneous injection of LMFS cells in the footpad, amputation of the leg was performed every 5 days from day 5 to day 20, and mice were killed at day 25 under anesthesia. The LMFS cells proliferated at the inoculation site (100% take), and all mice operated after day 15 had metastatic nodules spontaneously in the liver. Local recurrence was not observed in any cases. Liver weight was correlated with tumor growth in the liver. The combination therapy of operation and HCFU was examined in comparison with the footpad injection model. The foot on the injection side was amputated on day 12 with or without HCFU administration, and mice were sacrificed on day 33 under anesthesia. Histological liver metastases were as follows: 1. no treatments: 100%; 2. early phase chemotherapy without operation: 80%; 3. operation without chemotherapy: 80%; 4. postoperative chemotherapy: 20%; 5. preoperative chemotherapy: 40%; and 6. late phase chemotherapy without operation: 100%. These results indicate that operation with chemotherapy is the most useful treatment for liver metastases. Using this liver metastatic model, we are investigating a new combination therapy of operation and anti-cancer drugs for liver metastases.

Primary cemented total hip arthroplasty: five to twelve year clinical and radiographic follow-up.

A retrospective clinical and roentgenographic study was completed on 131 primary cemented total hip arthroplasties with a minimum of five years follow-up (mean, seven years; range, five to twelve years). Second generation cement technique including plugging of the medullary canal, cement gun filling, and pressurization of the canal was used. Acetabular cement was also pressurized. The total mechanical failure rate of the acetabular components was 18.4% compared to that of the femoral components which was 3.1%. There was a significantly higher incidence of acetabular component failure in rheumatoid arthritis patients (38.9%) compared to a preoperative diagnosis of primary osteoarthritis (14.1%) (p = 0.013). Yet there were no rheumatoid arthritis patients in the femoral component revision group. There were no differences in revision rates for metal-backed versus nonmetal-backed cups (p = 0.113). The average thickness of the proximal medial cement mantle was 2.8 millimeters in the loosening group and 5.4 millimeters in the nonloosening group (p = 0.333). All failures occurred in those patients whose proximal medial cement mantle was less than five millimeters. The authors strongly endorse the use of hybrid total hip arthroplasty and emphasize the need for meticulous surgical technique especially in obtaining a cement mantle of sufficient thickness in the proximal medial aspect of the femur.

Frequency of anesthetic cardiac arrest and death in the operating room at a single general hospital over a 30-year period.

STUDY OBJECTIVES: To determine the anesthetic cardiac arrest (CA) and death rates in the operating room (OR) and to determine whether anesthetic CA and death are preventable. DESIGN: Prospective study. SETTING: OR suite of a general teaching hospital. PATIENTS: 85,708 patients undergoing surgery over a 30-year period. MEASUREMENTS AND MAIN RESULTS: Anesthetic CAs and deaths were identified, their causes and preventability were determined on the day of occurrence, and they were recorded over the years 1962 to 1992. Four anesthetic CAs (0.5 arrest per 10,000 anesthetics) and 1 death (0.1 death per 10,000 anesthetics) occurred during the 30-year study period. CONCLUSIONS: The results of 30 years' experience do not support the hypothesis that all anesthetic CAs and deaths are preventable. However, careful clinical management can reduce their frequency to a level lower than those reported in the referenced literature.

Mechanism of transient mental nerve paraesthesia in sagittal split mandibular ramus osteotomy.

We investigated the mechanism involved in paraesthesia associated with sagittal split mandibular ramus osteotomy by three-dimensional computed tomography (3-D CT). Ten female patients underwent this procedure between 1988 and 1991. The inferior alveolar neuro-vascular bundles remained intact during the sagittal osteotomy in all cases. We examined the changes in the shape of the foramen mandibulae over a period of 6 months during which the transient mental nerve paraesthesia was recovered, and studied the distance from the foramen mandibulae to the spina mentalis (F-S distance) as measured on 3-D film. The postoperative 3-D CT scan showed bone resorption in front of the foramen mandibulae, and the F-S distance was shortened by an average of 2.94 mm. These findings suggest that possible causes of the paraesthesia is due to compression of the nerve trunk resulting from posterior movement of the mandibular ramus.

Xeroderma pigmentosum variant associated with multiple skin cancers and a lung cancer.

A 65-year-old Japanese man with a xeroderma pigmentosum (XP) variant, XP127TO, is described. The XP127TO skin fibroblasts exhibited the typical XP variant characteristics of a 1.5-fold higher sensitivity than normal cells to the lethal effect of 254 nm ultraviolet (UV) light and the normal level of unscheduled DNA synthesis induced by 254 nm UV. Caffeine dose-dependently increased the cytotoxic effect of 254 nm UV on XP127TO cells. Clinically, the patient developed not only 3 cutaneous squamous cell carcinomas on sun-exposed areas but also an adenocarcinoma of the upper lobe of the right lung. A review of the 14 documented Japanese XP patients with nonskin malignancies indicates that the incidence of nonskin malignancy in XP patients is much lower than that of skin cancer in XP but higher than that in the general population.

[Ferrographic analysis of synovial fluid in total hip replacement].

A synovial fluid analysis was carried out on 84 patients with total hip replacements, 53 of which were revision cases. The analysis was done using ferrography. An animal study was carried out whereby alumina ceramic, polyethylene and polymethyl methacrylate particles were inserted into the knees of rabbits, the synovial fluid of which was analysed. In addition, the synovium and surrounding tissues were histologically analysed. One week after insertion of the particulate debris only a few particles were noted in the synovial fluid and none at two weeks post insertion. However, these particles were noted in the synovium and surrounding tissues. Therefore, it was concluded that wear particles, following total hip replacement, may be encapsulated in the early period by the capsule and synovium, and have no adverse affect on the lubricating kinetics of the joint. It is postulated that the difference in tissue reaction to each of these particles may be responsible for the subsequent loosening.

Role of the kinin-kallikrein system in the vasodilator action of an angiotensin converting enzyme inhibitor (captopril) on the systemic resistance and capacitance vessels of dogs.

We investigated the vasodilator effects of captopril (CAP) on the systemic capacitance and resistance vessels by measuring changes in the mean circulatory pressure (MCP) and total peripheral resistance (TPR) that occurred in response to the intravenous injection of CAP (1 mg/kg) in open-chest dogs. The following five groups of dogs received CAP: (1) Group of untreated dogs, (2) TSA Group in which the dogs were subjected to total spinal anesthesia (TSA), (3) Ang II Group in which the dogs received a continuous intravenous infusion of angiotensin II (Ang II), (4) APR + Ang II Group in which the dogs received a continuous intravenous infusion of Ang II after pretreatment with aprotinin (APR, 25,000 K.I.E.), a kallikrein inhibitor, and (5) IND + APR + Ang II Group in which the dogs received a continuous intravenous infusion of Ang II after pretreatment with indomethacin (IND, 5 mg/kg), a prostaglandin synthesis inhibitor, and APR. 1) CAP significantly decreased TPR and MCP in the untreated Group. 2) CAP significantly decreased TPR and MCP in the TSA Group. There were no significant differences in percentage change of TPR (% delta TPR) and percentage change of MCP (% delta MCP) between the untreated and TSA Groups. 3) In the Ang II Group, CAP decreased the elevated TPR significantly, but hardly affected the elevated MCP. 4) CAP significantly decreased TPR without significant change in MCP in the APR + Ang II Group. The % delta TPR was significantly smaller in this Group than in the Ang II Group. 5) CAP significantly decreased TPR without significant change in MCP in the IND + APR + Ang II Group.(ABSTRACT TRUNCATED AT 250 WORDS)

[Does methylprednisolone potentiate the effects of dobutamine during thoracic epidural analgesia?].

The cardiovascular effects of dobutamine (DOB) combined with methylprednisolone (MP) were studied during thoracic epidural analgesia (TEA) in 59 patients undergoing operations on upper abdomen. To establish TEA, 8-10 ml of lidocaine 20 mg.ml-1 was injected into the epidural space through the T8-T9 interspace. The patients was intubated after fentanyl 0.2 mg, thiopental 3 mg.kg-1 and vecuronium 0.2 mg.kg-1. Anesthesia was maintained with 67% N2O, 33% O2 and 0.6% enflurane and DOB was infused at a rate of 5 micrograms.kg-1.min-1 during the surgical operation. Systolic blood pressure and urinary output after TEA did not decrease in the two groups, pretreated with MP 5 mg.kg-1 one hour or immediately before TEA, but decreased in the control group without MP injection. Heart rate showed no significant changes after TEA in all groups. We conclude that MP may potentiate the cardiovascular effects of DOB during TEA.

Miniature membrane oxygenator for use in neonatal ECMO.

A new miniature membrane oxygenator (Kuraray KMO, size, 0.3 m2, with a priming volume of 47 ml, compliance of less than 0.1 ml/100 mmHg, and pressure loss of 45 mmHg) with improved gas transfer and mechanical durability was developed and tested. The membrane material is a hollow fiber double layer polyolefin. The testing procedures determined by the AAMI were followed, and the results showed improved O2 and CO2 transfer (70 ml/min and 55 ml/min, respectively). Hemolysis was within acceptable limits, and plasma leakage was undetectable after 7 days of perfusion. Clinical study demonstrated satisfactory performance.

Nicardipine inhibits the endothelin-1-induced constriction of systemic capacitance and resistance vessels.

We estimated the effects of intravenous injection of endothelin-1 (ET-1; 400 pmol/kg) on the systemic capacitance and resistance vessels in anesthetized mongrel dogs by measuring changes in the mean circulatory pressure (MCP) and total peripheral resistance (TPR), respectively. In addition, the present study investigated the inhibiting action of nicardipine (NIC; 10 micrograms/kg bolus injection followed by 1.0-2.0 micrograms/kg/min continuous infusion) against the vasoconstrictor action of ET-1. We examined the effects of ET-1 (30 to 1,000 pmol/0.1 ml) on the femoral arterial system by measuring the percent changes in the perfusion pressure (% delta PP) of the femoral artery perfused with a constant flow, and investigated the effect of NIC on the vasoconstrictor action of ET-1 in this preparation. We obtained the following results: (a) Intravenous injection of ET-1 raised both TPR and MCP. However, in the presence of NIC, ET-1 raised TPR without influencing MCP. (b) Intra-arterial injection of ET-1 caused a dose-dependent increase in % delta PP. NIC shifted the dose-response curve of ET-1 for % delta PP to the right in a parallel fashion.

Necrotizing buccal and cervical fasciitis.

A bite wound led to necrotizing fasciitis in the temporal space, the lateral pharyngeal space and the carotid sheath, indicative of a Streptococcus and Bacteroides infection, and was successfully treated with repeated incisions, radical debridement and antibiotic therapy.

[Elimination of mycoplasmas from cultured human cell lines utilizing a combination of two antibiotics, quinolone and a pleuromutilin derivative].

Forty three cultured human cell lines were treated with a combination of 2 antibiotics to eliminate contaminant mycoplasmas. One course of treatment was composed of consecutive 3 or 4 cycles. Each cycle grew cells in BM-1 (pleuromutilin derivative; Boehringer Mannheim) containing medium (10 micrograms BM-1/ml culture) for 3 days, alternating with MC-210 (quinolone; Dainihon Pharmaceutical) containing medium (0.625 micrograms MC-210/ml culture) for 4 days. No treatment failure was encountered with this procedure. Before treatments, 18 (90%) of 20 cell line samples were contaminated with mycoplasma, as tested by DNA hybridization method (MYCOPLASMA T.C. RAPID DETECTION SYSTEM; Gen-Probe Inc.). Out of 43 cell lines treated, 7 were reduced in growth and dropped out. Among the other 36 cell lines, 27 became negative, 5 borderline and 4 slightly positive to the mycoplasma detection. All of the latter 9 cell lines, treated with one more similar course, found to be free from mycoplasma. Six of the dropout lines were cured of mycoplasma by a second treatment, under modified culture conditions. The last cell line (NATO) was successfully treated with another lot of FCS. Thus, the procedure proved successful even in treating promiscuously infected cell lines.

The role of alpha 1- and alpha 2-adrenoceptors in canine systemic capacitance vessels--a study with measurement of mean circulatory pressure.

We investigated the presence of alpha-adrenoceptor subtypes in systemic capacitance vessels by examining the effects of alpha 1- and alpha 2-agonists or antagonists on the mean circulatory pressure (MCP). Dogs were anesthetized with pentobarbital, and after total spinal anesthesia, epinephrine was given intravenously to maintain mean blood pressure at about 80 mmHg. 1. With intravenous injection of phenylephrine (alpha 1-agonist, 10 micrograms/kg, n = 7), and of BHT 920 (alpha 2-agonist, 5 micrograms/kg, n = 7), MCP increased significantly from 9.8 +/- 0.4 (mean +/- SE) to 10.9 +/- 0.3 mmHg (+11.2%, p less than 0.01), and from 9.3 +/- 0.4 to 10.3 +/- 0.4 mmHg (+10.8%, p less than 0.05), respectively. 2. Intravenous injection of prazosin (alpha 1-antagonist, 150 micrograms/kg, n = 7) and of yohimbine (alpha 2-antagonist, 30 micrograms/kg, n = 7) decreased MCP significantly from 9.9 +/- 0.4 to 8.2 +/- 0.5 mmHg (-17.2%, p less than 0.01), and from 9.8 +/- 0.2 to 7.6 +/- 0.3 mmHg (-22.4%, p less than 0.01), respectively. 3. Intravenous injection of phenylephrine (10 micrograms/kg, n = 7) after pretreatment with prazosin (150 micrograms/kg) decreased MCP significantly from 9.5 +/- 0.3 to 7.8 +/- 0.3 mmHg (-17.9%, p less than 0.01). MCP decreased significantly from 9.9 +/- 0.3 to 8.2 +/- 0.3 mmHg (-17.2%, p less than 0.01) after intravenous injection of BHT 920 (5 micrograms/kg, n = 7) following pretreatment with yohimbine (30 micrograms/kg).(ABSTRACT TRUNCATED AT 250 WORDS)

[Dental treatment for children under general anesthesia].

A clinico-statistical survey was carried out on dental treatment for children under general anesthesia who visited the clinic of Pedodontic Department, Matsumoto Dental College Hospital during the period of 1986 to 1989. The number of cases subjected in this survey was 108 (57 boys 51 girls), aged from one year and 5 months to 8 years and 9 months. All of these patients were admitted to the hospital for 3 days and were treated under general anesthesia, using GOE in 107 cases (in 80 cases by nasal intubation, in 27 cases by oral intubation). One case was administrated by intravenous anesthesia with Ketamine. The results were as follows: 1. The patient ages of the patients ranged from one year 5 months to 8 years 9 months. 2. Thirteen percent of the patients were handicapped. Fifty three percent of the patients had to visit hospitals in remote areas. 3. The number of restored teeth per patient was 15 on the average. The teeth were treated with composite resin filling in 8.5 teeth, composite resin crown in 2.6 teeth, metal crown 3.6 teeth and other material in 0.8 (extraction). 4. Pulpal treatment was carried out on 42 percent of the subjected teeth. 5. The average anesthesia administration time was 3 hours and 28 minutes. No serious trouble was observed although minor complications were seen post-operatively such as high fever or vomiting in some cases.

Differential vasodilator effect of nitroglycerin on systemic capacitance and resistance vessels in anesthetized dogs, and the mechanism of its action--a study by measuring mean circulatory pressure and total peripheral resistance.

The aim of our studies was to examine if the baroreceptor reflex induced by intravenous injection of nitroglycerin (NG) nearly nullifies the vasodilator action of NG on the systemic capacitance vessels in dogs anesthetized with pentobarbital. We performed total spinal anesthesia (TSA) in open-chest dogs to eliminate the baroreceptor reflex. Dogs in which mean blood pressure (MBP) was maintained at about 100 mmHg by continuous intravenous infusion of epinephrine formed the TSA 100 group, and those in which MBP was maintained at about 70 mmHg formed the TSA 70 group. Dose-response curves relating 5-6 different doses (0.8 to 200 micrograms/kg) of intravenous NG, to changes in mean circulatory pressure (% delta MCP) and to changes in total peripheral resistance (% delta TPR), were constructed. These data were compared with those from untreated dogs. In addition, we also studied plasma catecholamine (CA) concentrations before and after the intravenous injection of NG. (1) There was no significant difference in the dose-response curves of NG for % delta TPR between the 3 groups. (2) There was no significant difference in the dose-response curves for % delta MCP between the 2 TSA groups. However, there was significant difference in the dose-response curves for % delta MCP between the TSA groups and the untreated dogs. The dose-response curves for % delta MCP in the TSA groups shifted upwards as compared with that of the untreated dogs. (3) In the TSA 100 group, there was no significant increase in the plasma CA concentrations with 100 micrograms/kg of NG. In the untreated group, intravenous injection of 12.5 micrograms/kg and 100 micrograms/kg of NG caused a dose-related fall in MBP and a dose-related rise in the plasma norepinephrine and epinephrine concentrations. Our results suggest that the vasodilator action of NG on the systemic capacitance vessels in the untreated dogs was counterbalanced partly by the vasoconstriction produced by the baroreceptor reflex, with its direct vasodilator effect masked when the hypotensive doses of NG were given acutely.