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61.
Justin W. Phillpott M.D. Leonard E. Swischuk M.D. Susan D. John M.D. 《Emergency radiology》1997,4(2):68-71
We reviewed plain radiographs of 215 pediatric patients with surgically proven appendicitis to study the value of plain radiography for diagnosis. 相似文献
62.
Early experience with laparoscopic abdominoperineal resection 总被引:4,自引:0,他引:4
Background: Laparoscopic abdominoperineal resection (LAPR) has not been fully evaluated as a technique in the treatment of rectal and
anal cancer or inflammatory bowel disease. The purpose of our study was to evaluate the early experience with laparoscopic
abdominoperineal resection at Washington University Medical Center.
Methods: A prospective analysis was performed on the first 21 patients undergoing the procedure at Washington University Medical Center.
Indications for surgery included rectal cancer (14 patients), anal squamous cell cancer (four patients), inflammatory bowel
disease (two patients), and anal melanoma (one patient).
Results: The procedure was converted to open procedure in four patients (19%). The mean (±SEM) operative time and blood loss for completed
and converted LAPR were 239 ± 11 min and 424 ± 43 ml, respectively. Postoperative hematocrit dropped a mean of 8.3% ± 1.2%
SEM; five patients required blood transfusion (24%). Wound complication occurred in four patients (19%; three perineal, one
trocar site). Bowel function returned after a mean of 3 days, and mean postoperative hospital stay for the completed LAPR
group was 5 days. Mild pain was experienced by 81% of patients (17/21) while 19% (4/21) noted moderate pain, usually of the
perineal wound. The mean duration of patient-controlled analgesia use was 2 days. During the 1–44-month follow-up, six patients
(29%) died from cancer (stage III or IV at operation) and only one patient developed local recurrence in the pelvis (5%).
There were no trocar-site implants of cancer. Furthermore, there was no relationship between prior abdominal operations, the
amount of blood loss, postoperative drop of hematocrit, or blood transfusion requirement and the length of hospitalization
or complication rates.
Conclusion: Laparoscopic abdominoperineal resection is a feasible alternative to the conventional open technique in both cancer and colitis
patients.
Received: 23 April 1996/Accepted: 8 July 1996 相似文献
63.
Laparoscopic cryosurgery for hepatic tumors 总被引:2,自引:0,他引:2
Background: Hepatic cryosurgery has been shown to be a safe technique that may be well suited to a laparoscopic approach.
Methods: The technical feasibility and safety of laparoscopic cryosurgery was explored first in a pig model. Thereafter we performed
the first successful case of laparoscopic hepatic cryosurgery at our institution.
Results: In the animal model, we found that it is possible to safely identify, target, and cryoablate specific lesions in the liver.
Temperature in the peritoneal cavity remained above 35°C, and pathologic examination of the abdominal wall around the cryoprobe
site revealed no damage. We also successfully treated a 62-year-old man with a metastatic colorectal carcinoma deep in the
right lobe of the liver with laparoscopic cryosurgery using a transpleural approach.
Conclusion: We conclude that laparoscopic cryosurgery is feasible for lesions anywhere in the liver. For lesions high on the dome of
the liver, a transpleural approach may provide better access. 相似文献
64.
Background: Increasingly larger series of laparoscopic fundoplications (LF) are being reported. A well-documented advantage of the laparoscopic
approach is shortened hospital stay. Most centers report typical lengths of stay (LOS) for LF of 2–3 days. Our success with
LF with a LOS of 1 day led to an attempt at performing LF on an ambulatory basis.
Methods: Sixty-one consecutive patients with appropriate criteria for LF underwent surgery at our institution. Patients were counseled
by the authors as to the usual postop course and progression of diet. All patients received preemptive analgesia (PEA) consisting
of perioperative ketorolac and preincisional local infiltration with bupivicaine. Anesthetic management included induction
with propofol, high-dose inhalational anesthetics, minimizing administration of parenteral narcotics, and avoidance of reversal
of neuromuscular blockade. Immediate postop pain management included parenteral ketorolac and oral hydro- or oxycodone. All
patients were given oral fluids and soft solids after transfer from the recovery room to the postoperative observation unit.
Two patients were excluded from ambulatory consideration due to excessive driving distance from our hospital. Another two
were hospitalized for observation after experiencing intraoperative technical problems.
Results: Of 57 patients in whom same-day discharge was attempted, there were three failures requiring overnight hospitalization: All
were due to pain and nausea; one patient also suffered transient urinary retention. There were no adverse outcomes related
to early discharge, and there were no readmissions. One patient returned to the emergency room after delayed development of
urinary retention. Median time from conclusion of operation to discharge was less than 5 h. No patients expressed dissatisfaction
with early discharge on follow-up interview.
Conclusions: LF can be safely performed as an ambulatory procedure. Analgesic and anesthetic management should be tailored to minimize
nausea and provide adequate pain control.
Received: 1 April 1996/Accepted: 29 May 1997 相似文献
65.
Camilla Nyboe Jonas A. Funder Morten H. Smerup Hans Nygaard J. Michael Hasenkam 《European journal of cardio-thoracic surgery》2006,29(6):1008-1013
Objective: Mechanical heart valves can cause thromboembolic complications, possibly due to abnormal flow patterns that produce turbulence downstream of the valve. The objective of this study was to investigate whether three different bileaflet valve designs would exhibit clinically relevant differences in downstream turbulent stresses. Methods: Three bileaflet mechanical heart valves (Medtronic Advantage®, CarboMedics© Orbis™ Universal and St. Jude Medical® Standard) were implanted into 19 female 90 kg pigs. Blood velocity was measured during open chest conditions in the cross sectional area downstream of the valves with 10 MHz ultrasonic probes connected to a modified Alfred® Pulsed Doppler equipment. As a measure of turbulence, Reynolds normal stress (RNS) was calculated at three different cardiac output ranges (3–4, 4.5–5.5, 6–7 L/min). Results: Data from 12 animals were obtained. RNS correlated with increasing cardiac outputs. The highest instantaneous RNS observed in these experiments was 47 N/m2, and the mean RNS taken spatially over the cross sectional area of the aorta during systole was between 3 N/m2 and 15 N/m2. In none of the cardiac output ranges RNS values exceeded the lower critical limit for erythrocyte or thrombocyte damage for any of the valve designs. Conclusions: Reynolds normal stress values were below 100 N/m2 for all three valve designs and the difference in design was not reflected in generation of turbulence. Hence, it is unlikely that any of the valve designs causes flow induced damage to platelets or erythrocytes. 相似文献
66.
New perspectives for the use of contrast-enhanced liver ultrasound in clinical practice 总被引:1,自引:0,他引:1
L. Bolondi J.M. Correas R. Lencioni H.P. Weskott F. Piscaglia 《Digestive and liver disease》2007,39(2):187-195
The introduction of second-generation microbubble ultrasound contrast agents and the development of contrast specific ultrasound techniques have improved the ability of contrast enhanced ultrasound in detecting and characterising liver lesions, offering new perspectives for its exploitation in clinical hepatology. Indeed, several studies have demonstrated a high diagnostic accuracy in focal lesion characterisation (85-96%) in patients either with or without underlying chronic liver disease. This review article describes the basic principles of contrast enhanced ultrasound, defines the different vascular features of benign and malignant liver lesions, and assesses its clinical impact in different clinical scenarios, according to the guidelines of the European Federation of Societies for Ultrasound in Medicine and Biology, contrast enhanced ultrasound enables the characterisation of focal liver lesions, regardless of the presence or absence of underlying chronic liver disease. Contrast enhanced ultrasound is also useful in staging and follow-up of cancer patients and in monitoring local ablative treatment. Contrast enhanced ultrasound is expected to be considerably increased and replace many computed tomography and magnetic resonance imaging examinations in near future, according to the European Federation of Societies for Ultrasound in Medicine and Biology guidelines. Therefore, it is necessary to take measures in order to meet the demand for an increasing number of these procedures. 相似文献
67.
Y Miyamoto M Nakatani M Ida T Ishikawa N Okazawa M Ariizumi F Tsujimoto K Mizunuma Y Fukuda S Tada 《Journal of clinical ultrasound : JCU》1989,17(5):309-318
Ultrasonography was performed in 45 cases of gastric cancer. Specimens from all 45 cases of gastric cancer were subjects to ultrasonographic study by the water immersion method for comparison with histology. In 32 of these 45 cases in vivo ultrasonographic evaluation was performed prospectively. The overall accuracy rates for the diagnosis of the depth of cancerous invasion were almost 80% in both in vitro and in vivo studies. In vivo ultrasonographic findings agreed well with those from the specimen studies. Ultrasonography was considered to be useful in the diagnosis of gastric malignancies. 相似文献
68.
L. Rosenthall 《Calcified tissue international》1997,61(2):139-141
This study was designed to determine the changes in precision of the ultrasound parameters speed of sound (SOS), broadband
ultrasound attenuation (BUA), and stiffness index (SI) as a function of bone quality. The instrument used in this investigation
was the LUNAR Achilles. Of the 608 female patients who had paired measurements with repositioning, 200 had t scores ≥−1 and 408 had t scores ≤−2.5, thus rendering a normal and a grossly abnormal group for comparison of precision results. It was found that
the median precision error (CV%) for BUA was 1.99% for normal bone and 1.44% for abnormal bone (P= 0.02). No significant difference was obtained between median precision errors in normal and abnormal bone for the parameters
SOS and SI, which were 0.23% and 0.19%, and 2.15% and 2.02%, respectively. In the interquartile range, the mean precision
errors for SOS and BUA were significantly different in normal and abnormal bone: SOS was 0.25% and 0.21%, respectively, and
BUA was 2.31% and 1.85%, respectively. No significant change was registered for SI. Precision error appears to decrease slightly
at lower values for calcaneal variables.
Received: 21 August 1996 / Accepted: 5 March 1997 相似文献
69.
Conversions and complications in 185 laparoscopic adjustable silicone gastric banding cases 总被引:9,自引:3,他引:6
E. Chelala G. B. Cadiére F. Favretti J. Himpens M. Vertruyen J. Bruyns L. Maroquin M. Lise 《Surgical endoscopy》1997,11(3):268-271
Background: Kuzmak's gastric silicone banding technique is the least invasive operation for morbid obesity. The purpose of this study
was to analyze the complications of this approach.
Methods: Between September 1992 and March 1996, 185 patients underwent laparoscopic gastroplasty by the adjustable silicone band technique.
A minimally invasive procedure using five trocars was performed.
Results: In 11 patients exposure of the hiatus was impeded because of hypertrophy of the left liver lobe which led to conversion in
eight patients and abortion of the procedure in three other patients. Anatomical complications: We observed two gastric perforations
and one band slippage at the early stage, one infection and three rotations of the access port. Functional complications:
There were eight (4%) cases of irreversible total food intolerance resulting in pouch dilation and eight cases (4%) of esophagitis.
One fatality on the 45th day in a patient with a Prader-Willi syndrome.
Conclusion: The most disturbing complications of gastric banding technique are gastric perforation and pouch dilation. Their incidence
may be reduced by improving the technique and by considering pitfalls of the procedure.
Received: 28 May 1996/Accepted: 25 July 1996 相似文献
70.
Yair Lotan Matthew T Gettman Claus G Roehrborn Margaret S Pearle Jeffrey A Cadeddu 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2003,7(2):111-115
BACKGROUND AND OBJECTIVES: To evaluate the experience with laparoscopic nephrectomy in a large county hospital and perform a cost comparison between uncomplicated open and laparoscopic nephrectomy. METHODS: Eleven consecutive patients who underwent an uncomplicated laparoscopic nephrectomy in a large county hospital were compared with 8 patients who underwent uncomplicated open nephrectomy during the same period. Patient charts and corresponding billing records were reviewed to determine overall hospitalization cost and individual cost components. RESULTS: No perioperative complications occurred in either the laparoscopic or open group, and no statistically significant differences existed between groups with regard to patient demographics or operative parameters. The overall operating room costs favored the open nephrectomy group by dollars 1070 (P=0.003). However, the overall cost of hospitalization, surgeon professional fees, duration of hospitalization, room and board costs, laboratory, and radiology costs, pharmacy costs, intravenous solution and infusion pump costs all significantly favored the laparoscopic patient group. The mean difference in overall hospital cost between laparoscopic and open nephrectomy was dollars 1211 in favor of laparoscopy (P=0.037). CONCLUSIONS: Our experience with laparoscopic nephrectomy in a large county hospital demonstrates a clear economic advantage in favor of the laparoscopic approach. Given limited funding for public hospitals and a clear patient benefit, laparoscopic nephrectomy should constitute first-line therapy when nephrectomy is indicated. 相似文献