1.A Case of Inflammatory Abdominal Aortic Aneurysm Whose Persistent Postoperative High Fever Was Successfully Treated by Steroid
Norio Uchida ; Masataka Yamazaki
Japanese Journal of Cardiovascular Surgery 2003;32(3):132-136
The indications of steroid therapy for inflammatory abdominal aortic aneurysm (IAAA) is controversial. We here report a rare case whose persistent postoperative high fever and duodenal obstruction due to adhesion to the residual aortic wall were successfully treated by steroid. A 73-year-old man was referred to our hospital because of abdominal pain and a pulsating mass in his umbilical region. CT scan showed a remarkably dilated infrarenal abdominal aorta (10cm in diameter) with a mantle sign. Preoperatively C-reactive protein (CRP) was high, however temperature was normal. We replaced the aneurysm with a bifurcated prosthetic graft (18×9mm collagen impregnated knitted Dacron) by laparotomy on April 10, 2001. The aneurysm showed a thick and fibrous surface tightly adhering to the jejunum, sigmoid colon and ureters. We tried to minimize surgical injury to perianeurysmal fibrotic tissue. However the right ureter was injured and repaired using a double-J catheter. Histopathological examination revealed lymphoplasmocystic infiltration in the wall of the aorta, which was compatible with IAAA. From the 10th postoperative day high fever (38 to 39°C) persisted and CT revealed perigraft seroma with air density. Graft infection was suspected and the perigraft fluid was drained by puncture. However cultures of the serous fluid was negative. Moreover, approximately 1, 500ml gastric juice was drained per day via a nasogastric tube. Therefore we suspected postoperative inflammatory reactions to the impregnated Dacron graft and/or inflammation of the residual aortic wall. This patient was given 20mg prednisolone intravenously 18 days after the operation and the dose of steroid was then tapered. This therapy had an obvious effect on the recovery of the general condition. Body temperature and CRP was normal when he was discharged 46 days after surgery. The patient had no complaints and the thickness of the residual aortic wall around the graft was found to have decreased one year after the operation on follow up CT.
2.Enhanced performance of maximum vertical jump by arm movement.
YOSHIHIKO YAMAZAKI ; MASATAKA SUZUKI ; TADAAKI MANO
Japanese Journal of Physical Fitness and Sports Medicine 1992;41(2):261-272
The effects of an arm lifting movement (ALM) on maximum vertical jumps with all but the ankle joints fixed (propelled only by plantar flexion) were studied in five subjects. ALM increased flight time, but did not alter maximum angular velocity of the ankle before takeoff. Holding 4kg dumbbells in their hands enhanced the effect of ALM on flight time. ALM increased the maximum force and the force at the onset of plantar flexion. Elbow angle recordings showed that both arms were accelerated before or around plantar flexion onset, and decelerated mainly after takeoff. In another series of experiments, we measured the vertical component of head and hand acceleration with accelerometers. ALM produced positive acceleration of the head after takeoff, which was related to negative acceleration of the hand. The results suggest that ALM increased flight time by enhancing plantar flexion torque under suppression of ankle angular velocity before takeoff. We discussed the relationship between this suppression and different acceleration between the arms and the body except the arms.
3.The use of a novel in-bed active Leg Exercise Apparatus (LEX) for increasing venous blood flow
Kenta Tanaka ; Hiroshi Kamada ; Yukiyo Shimizu ; Shizu Aikawa ; Tomofumi Nishino ; Naoyuki Ochiai ; Masataka Sakane ; Masashi Yamazaki
Journal of Rural Medicine 2016;11(1):11-16
Objective: The incidence of pulmonary embolism (PE) and leg deep vein thrombosis (DVT) has increased in recent years in association with aging and an increase in the number of bedridden individuals. We developed an active in-bed leg exercise apparatus labeled the Leg Exercise Apparatus (LEX) for DVT prevention. We compared the effect of leg exercises performed using the LEX to conventional active ankle exercises on increased blood flow.
Materials & Methods: The subjects were eight healthy adult volunteers [five men and three women, aged 20–34 (mean 27.0) years]. Subjects performed two types of exercise; exercise 1 consisted of leg exercises using the LEX, while exercise 2 consisted of in-bed active plantar flexion/dorsiflexion exercises without the device. Measurements were taken 1, 5, 10, 20, and 30 minutes after exercise including common femoral vein blood flow, mean blood flow velocity, maximum blood flow velocity, and vessel diameter using Doppler ultrasound. Statistical procedures included timed measurement data analysis using a linear mixed model. A Bonferroni correction was used for multiple comparisons.
Results: Compared to resting levels, blood flow reached a maximum value 1 minute after exercise for both exercise types, with a significantly greater increase after exercise 1 (1.76-fold increase) compared to exercise 2 (1.44-fold increase) (p = 0.005). There was a significant difference (p = 0.03) between the two exercises for all values from 1 minute to 30 minutes following exercise. There was no significant difference between exercises for peak or mean blood flow velocity. Compared to resting levels, blood vessel diameter reached a maximum value of 1.47-fold greater at 5 minutes post-exercise for exercise 1 and a maximum value of 1.21-fold greater at 1 minute post-exercise for exercise 2.
Conclusions: Exercise using the LEX increased lower leg venous blood flow and vessel diameter. We propose that the LEX may serve as a new DVT prevention tool.
4.Tumor Occupation in the Spinal Canal and Clinical Symptoms of Cauda Equina Schwannoma: An Analysis of 22 Cases.
Kengo FUJII ; Masataka SAKANE ; Tetsuya ABE ; Tsukasa NAKAGAWA ; Shinsuke SAKAI ; Masaki TATSUMURA ; Toru FUNAYAMA ; Masashi YAMAZAKI
Asian Spine Journal 2016;10(6):1079-1084
STUDY DESIGN: Retrospective, radiological study. PURPOSE: To determine the relationship between clinical symptoms and the extent of tumor occupation of the spinal canal by cauda equina schwannoma. OVERVIEW OF LITERATURE: Little is known about the relationship between the size of tumors of the cauda equina and the manifestation of clinical symptoms. We analyzed this relationship by estimating the percentage of tumor occupation (PTO) in the spinal canal in cauda equina schwannomas and by correlating this parameter with the presence and severity of clinical symptoms. METHODS: Twenty-two patients (9 men and 13 women; age, 19–79 years; mean age, 55.3 years) who were radiologically diagnosed with schwannomas of the cauda equina between April 2004 and July 2014 were retrospectively analyzed. PTO was measured in axial and sagittal magnetic resonance imaging slices in which the cross-sectional area of the tumor was the largest. Data regarding clinical symptoms and results of physical examinations were collected from patient medical records. PTO differences between symptom-positive and -negative groups were analyzed for each variable. RESULTS: In the 4 cases in which tumor presence was not related to clinical symptoms, PTO was 5%–10% (mean, 9%) in axial slices and 23%–31% (mean, 30%) in sagittal slices. In the 18 cases in which symptoms were associated with the tumor, PTO was 11%–86% (mean, 50%) in axial slices and 43%–88% (mean, 71%) in sagittal slices. PTO in axial slices was significantly higher in the presence of Déjèrine symptoms and/or muscle weakness, a positive straight leg raise test, and a positive Kemp sign. CONCLUSIONS: PTO >20% in axial slices and >40% in sagittal slices can be an indication of symptomatic cauda equina schwannoma.
Cauda Equina*
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Female
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Humans
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Leg
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Magnetic Resonance Imaging
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Male
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Medical Records
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Muscle Weakness
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Neurilemmoma*
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Occupations*
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Physical Examination
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Retrospective Studies
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Spinal Canal*
5.Simultaneous Three-Dimensional Analysis of Cervical Spine Kinematics in the Axial and Sagittal Views during a Simulated Frontal Impact: Differences between Tensed and Relaxed States.
Keita NAKAYAMA ; Masataka SAKANE ; Susumu EJIMA ; Daisuke ITO ; Tomofumi NISHINO ; Sou KITAJIMA ; Masashi YAMAZAKI
Asian Spine Journal 2015;9(6):876-883
STUDY DESIGN: Prospective experimental study on humans. PURPOSE: To determine whether postural differences during a low-speed impact are observed in the sagittal and axial views, particularly in a relaxed state. OVERVIEW OF LITERATURE:: Three-dimensional motion capture systems have been used to analyze posture and head-neck-torso kinematics in humans during a simulated low-speed impact, yet little research has focused on the axial view. Since a seatbelt asymmetrically stabilizes a drivers right shoulder and left lower waist into the seat, it potentially creates movement in the axial view. METHODS: Three healthy adult men participated in the experimental series, which used a low-speed sled system. The acceleration pulse created a full sine shape with a maximum acceleration of 8.0 m/s2 at 500 ms, during which the kinematics were evaluated in relaxed and tensed states. The three-dimensional motion capture system used eight markers to record and analyze body movement and head-neck-torso kinematics in the sagittal and axial views during the low-speed impact. Head and trunk rotation angles were also calculated. RESULTS: Larger movements were observed in the relaxed than in the tensed state in the sagittal view. The cervical and thoracic spine flexed and extended, respectively, in the relaxed state. In the axial view, larger movements were also observed in the relaxed state than in the tensed state, and the left shoulder rotated. CONCLUSIONS: During simulated frontal impact, the rotation angle between the head and trunk was significantly larger in the relaxed state. Therefore, we recommend also observing movement in the axial view during impact tests.
Acceleration
;
Adult
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Biomechanical Phenomena*
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Head
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Humans
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Imaging, Three-Dimensional
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Male
;
Posture
;
Prospective Studies
;
Shoulder
;
Spine*
;
Transcutaneous Electric Nerve Stimulation*
6.Prevention of SSI in Cardiac Surgery by Using Intraoperative Measures for High-Risk Patients as Standard Precautions against Mediastinitis
Shingo TAGUCHI ; Makoto HANAI ; Masataka YAMAZAKI ; Makoto SUMI ; Humitake MOMOKAWA
Japanese Journal of Cardiovascular Surgery 2022;51(2):80-88
Background : Risk factors for surgical site infection (SSI) are thought to include poorly controlled diabetes mellitus, dialysis, and a long operating time, but patients without risk factors can also develop infection. Therefore, it is possible that SSI could be prevented by routinely using the precautions against SSI developed for high-risk patients. We investigated the route and pathogenetic mechanism of mediastinitis, which is the most frequent SSI after cardiac surgery. We hypothesized that mediastinitis occurred when the deep sternal marrow was contaminated by skin bacteria. Based on this hypothesis, we investigated the efficacy of various intraoperative prophylactic methods for preventing mediastinitis. Methods : We evaluated 658 patients undergoing cardiac surgery at our institution between April 2011 and July 2016. They were classified into two groups. Group C comprised 406 patients who received standard insertion of a sternal retractor after sternotomy. Group S was 252 patients in whom a retractor was inserted after covering the sternal marrow with oxidized cellulose hemostats and belt-like thin towels, with surplus parts of the towels being used to fill subcutaneous dead space at the superior and inferior margins of the midline wound. We investigated the following 10 risk factors for mediastinitis: diabetes (HbA1c≥7.5), renal failure (Cr≥2), smoking, obesity (BMI≥30), reoperation, urgent/emergency operation, intubation in the preoperative period, long operating time (≥8 h), reopening the chest for hemostasis, and coronary artery bypass grafting (CABG). Factors associated with mediastinitis were determined using univariate modeling analysis followed by multi-variate logistic regression analysis. Results : Mediastinitis occurred in 13 patients (2.0%). The significant risk factor for mediastinitis were urgent/emergency operation and CABG, but 1 patient had no risk factors. A univariate analysis showed statistical significance in CABG, presence of maneuver covering the sternal marrow, JapanSCORE-II in mortality and deep sternum infection (DSI). Reopening the chest for hemostasis, CABG, aortic aneurysm, plural risk factors, and JapanSCORE-II in DSI were identified as a risk factor by multiple logistic regression, not all factors showed a significant difference. Mediastinitis only occurred in group C, and it was significantly less frequent in group S with additional precautions against infection including propensity score matching analysis (p<0.05). Conclusion : When the bone marrow of the transected sternum was covered tightly to protect it from contamination by skin bacteria during cardiac surgery, the frequency of postoperative mediastinitis was significantly reduced.