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961.
Ingestion of sodium hypochlorite bleach is usually benign, leading most poison centers to advocate conservative, home management. We report a rare, fatal case of household bleach ingestion. A 66-y-old female ingested an unknown quantity of regular CLOROX bleach (5.25% sodium hypochlorite, pH = 11.4). Upon discovery, she was vomiting spontaneously, and had slurred speech and oral mucosal discoloration. On hospital arrival the patient became unresponsive with shallow respirations. Laboratory studies revealed hypernatremia (169 mEq Na/L), hyperchloremia (143 mEq Cl/L), and metabolic acidosis (5 mmol total CO2/L). Radiographic evaluation showed bilateral pneumothoraces and pneumoperitoneum. The patient was intubated and ventilated, hypotension was treated with fluid resuscitation, and metabolic acidosis corrected with sodium bicarbonate. Naloxone and flumazenil were given without effect, and thoracostomy tubes were placed. Rapid deterioration of vital signs and mental status ensued, with cardiorespiratory arrest from which she was resuscitated. A second cardiac arrest resulted in death. Autopsy revealed esophageal and gastric mucosal erosions, perforation at the gastroesophageal junction, and extensive necrosis of adjacent soft tissue. Stomach contents contained sodium hypochlorite, and pleural and peritoneal fluid had the aroma of bleach. Postmortem vitreous humor Na was 187 mEq/L and Cl was 169 mEq/L. Toxicologic analysis revealed meprobamate metabolites in the urine, and lidocaine in the blood. The literature regarding fatal bleach ingestion is reviewed.  相似文献   
962.
Therapeutic intervention with complement and beta-glucan in cancer.   总被引:17,自引:0,他引:17  
Complement (C) has two major effector systems available for host defense. The membrane attack complex (MAC) generated from components C5-C9 can form membrane-penetrating lesions that lead to cell death by causing a rapid loss of cytoplasmic components. The MAC is only effective against pathogens with outer phospholipid membranes, and cannot kill gram-positive bacteria or yeast whose membranes are protected by cell walls. The most important effector mechanism of C is the opsonization of microbial pathogens with the serum protein C3 that leads to their high avidity attachment to the C3-receptors of phagocytic cells. Pathogens that activate complement are first coated with the C3b fragment of C3, which is rapidly proteolyzed into the iC3b fragment by serum factor I. These iC3b fragments serve to promote the high avidity attachment of the 'iC3b-opsonized' pathogens to the iC3b-receptors (CR3, CD11b/CD18) of phagocytic cells and natural killer (NK) cells, stimulating phagocytosis and/or cytotoxic degranulation. Host cells, including neoplastic tumor cells, have been endowed with natural mechanisms for self-protection against both the MAC and the cytotoxic activation of CR3. This review discusses a novel type of immunotherapy for cancer that uses soluble yeast beta-glucan to override the normal resistance of iC3b-opsonized tumor cells to the cytotoxic activation of phagocyte and NK cell CR3, allowing this important effector mechanism of the C system to function against tumor cells in the same way that it normally functions against bacteria and yeast. Moreover, the cytotoxic activation of beta-glucan-primed NK cell CR3 by iC3b-opsonized tumors is shown to be accompanied by a tumor-localized secretion of the cytokines TNFalpha, IFNalpha, IFNgamma, and IL-6.  相似文献   
963.
PURPOSE: The aim of this study was to assess various intraoperative and postoperative complications associated with laparoscopic colorectal surgery. Specifically, the impact of surgical experience and procedure type on complications was analyzed. METHODS: All patients who underwent laparoscopic surgery were analyzed by age, sex, surgical indications, procedure performed, procedure length, intraoperative and postoperative complications, incidence and causes for conversion, duration of postoperative ileus, and length of hospital stay. Patients were classified for type of procedure and chronologically into four consecutive groups. Procedures were also categorized into four different groups: GI, total abdominal colectomies; GII, segmental resections; GIII, diverting procedures; GIV, others (abdominoperineal resection, Hartmann's creation or closure, anterior resection, and rectopexy). RESULTS: Between August 1991 and October 1995, 167 patients of a mean age of 49.6 (15–88) years underwent laparoscopic colorectal procedures. All procedures were electively performed. Common indications for surgery included inflammatory disease in 70 (42 percent), neoplasia in 56 (33 percent), functional bowel disorders in 30 (18 percent), and other forms of colorectal disorders in 11 (7 percent) patients. The most significant variable affecting intraoperative laparoscopic complication rate was surgical experience measured as the time interval during which surgery was performed (P=0.02). Total complication rate decreased from 29 percent during the first period to 11 percent by the second period (P<0.04) and 7 percent during the third period (P<0.005). Thus, the learning curve appeared to have required more than 50 cases to achieve. Moreover, even after performance of 94 (1991–1993) procedures in GI and GIV, these procedures were associated with higher complication rates than were those procedures in GII and GIII (P=0.04). CONCLUSION: Surgical experience and case selection are the most critical variables by which the surgeon can decrease the intraoperative laparoscopic complication rate.  相似文献   
964.
Laparoscopy for colonic diseases began in 1990 and has established a role in benign disease. Early observations and experiences demonstrated feasibility of laparoscopic surgery for a variety of colonic disease processes, but the applicability to colonic carcinoma was unclear. METHODS: In 1990, we began a comparative study of open (OCR)vs.laparoscopic (LCR) approach to colon cancer. The study progressed 65 months, with 224 patients in OCR group and 191 patients in LCR group. Parameters studied are stage, location, length of specimen, number of lymph nodes resected, margins, postoperative course, wound complications, recurrence rates, and immediate and long-term survival. OCR were standardized by one group, and LCR were standardized by a second group. All patients undergoing LCR were given freedom to choose either OCR or LCR, and informed consent was obtained. RESULTS: Equal or greater lymph node retrieval, resections, and distal margins were evident with LCR. Benefits with LCR were shown with shorter hospitalization (5.7vs.9.7 days), less blood loss, less wound problems (1vs.14), and quicker return of bowel function. Survival, recurrence, and death rates were essentially the same. There were no trocar implants in the LCR group. CONCLUSION: After five years, this study shows that laparoscopy does no harm to the patient, offers comparable oncologic resections, and seems to be patient-friendly, with less pain, quicker return of bowel functions, shortened hospitalization, and quicker return to full activity.  相似文献   
965.
In the GUSTO-I ECG ischaemia monitoring substudy, 1067 patientsunderwent continuous ST segment monitoring, using vector-derived12-lead (406 patients), 12-lead (373 patients) and 3-lead Holter(288 patients) ECG recording systems. Simultaneous angiogramsat 90 or 180 min following thrombolytic therapy were performedas a part of the prospective study in 302 patients. Infarct vessel patency was established as TIMI perfusion grades2 or 3 and occlusion as TIMI perfusion grades 0 or 1. Coronaryartery patency was predicted from ST trends up to the time ofangiography. Predictive values at 90 and 180 min after the startof thrombolysis were 70% and 82% for patency and 58% and 64%for occlusion, respectively. In retrospect, accuracy appearedgreatest (79–100%) in patients with extensive ST segmentelevation (400 µV), if both speed of ST recovery and extentof ST segment: elevation were taken into account. Although thethree recording systems differed considerably in signal processing,no significant difference in accuracy was demonstrated amongthese systems. We conclude that continuous ECG monitoring may help select highrisk patients without apparent reperfusion who may benefit fromadditional reperfusion therapy. As ST recovery may occur earlyafter the start of thrombolytics and accuracy of the test isrelated to peak ST levels, the use of on-line ECG monitoringdevices on emergency wards and cardiac care units is recommended.(Eur Heart J 1996; 17: 689–698)  相似文献   
966.
OBJECTIVES: To define the clinical, neuropsychological, and radiological features of bilateral parietal lobe atrophy. METHODS: Four patients underwent a comprehensive longitudinal neuropsychological assessment, as well as MRI and HMPAO-SPECT. RESULTS: The consistent findings in the patients were early visuospatial problems, agraphia of a predominantly peripheral (or apraxic) type, and difficulty with bimanual tasks, all of which outweighted deficits in memory and language until later in the course of the illness. As the disease progressed, impairments in the phonological aspects of language and in auditory-verbal short term memory were often striking, perhaps reflecting spread from the parietal lobe to perisylvian language areas. Three patients went on to develop a global dementia and fulfilled the criteria for a clinical diagnosis of probable Alzheimer's disease; the fourth patient has only recently been identified. Neuroimaging disclosed bilateral parietal lobe atrophy (MRI) and hypoperfusion (SPECT), which was out of proportion to that seen elsewhere in the brain. One patient has died and had pathologically confirmed Alzheimer's disease with particular concentration in both superior parietal lobes. CONCLUSIONS: Bilateral biparietal atrophy is a recognisable clinical syndrome which can be the presenting feature of Alzheimer's disease. Although the label "posterior cortical atrophy" has been applied to such cases, review of the medical literature suggests that this broad rubric actually consists of two main clinical syndromes with features reflecting involvement of the occipitotemporal (ventral) and biparietal (dorsal) cortical areas respectively.  相似文献   
967.

Purpose

To study the haemodynamic effects of intrathecal meperidine, administered either alone or mixed with bupivacaïne.

Methods

We studied 42 Chinese patients, aged 59–87 yr, scheduled for transurethral bladder or prostate surgery, randomized into three equals groups, that received either meperidine 0.8 mg · kg?1 meperidine 0.4 mg · kg?1 plus 1.5 ml of 0.5% heavy bupivacaïne or 3 ml of heavy bupivacaïne 0.5%. Non-invasive systolic (SAP) and mean (MAP) arterial pressures, central venous pressure and cardiac index, stroke index and heart rate (HR) measured by the BoMed NCCOM3-R7S bioimpedance device, were recorded over the first 25 min. Systemic vascular resistance index (SVRI) was derived. Onset of sensory and motor block was also measured. Decreases in MAP of 25% were treated with colloid and metaraminol. Results: The onset of block was slower in the meperidine group (P < 0.05). Decreases in SAP, MAP and SVRI (all; P < 0.001) occurred within five minutes in all three groups. The HR was increased in the bupivacaïne group (P = 0.03), but bradycardias treated with atropine occurred in six patients receiving meperidine and four patients receiving the mixture. Six patients receiving meperidine and two patients receiving the mixture required general anaesthesia for inadequate block. The incidence of nausea and vomiting was higher in the patients receiving meperidine (P < 0.05). No other complications were encountered.

Conclusions

Intrathecal meperidine used alone or mixed with bupivacaïne has no intra-operative advantage over heavy bupivacaïne 0.5%.  相似文献   
968.

Objective.

Antibiotic-sterilised homograft valves stored at 4 °C have been implanted in the subcoronary position in this unit since 1973. This study was undertaken in order to assess the longterm function of these valves.

Methods.

All 249 patients undergoing homograft aortic valve replacement (AVR) at the Wessex Cardiothoracic Centre between April 1973 and December 1994 were studied. Homograft valve sizes ranged from 15 mm to 28 mm internal diameter, 202 (81.1%) varying between 18 mm and 22 mm. The mean patient follow-up was 12.4 years with a total follow-up of 3096 patient-years. There were six early deaths (2.4%).

Results.

On actuarial analysis, survival was 78.5 ± 2.7% (1SE) at 10 years, 65.7 ± 3.3% at 15 years and 55.0 ± 3.9% at 20 years. The freedom from redo AVR was 87.9 ± 2.4% at 10 years, 71.7 ± 3.8% at 15 years and 49.7 ± 5.6% at 20 years. The freedom from structural degeneration was 85.5 ± 2.5% at 10 years, 63.6 ± 4.0% at 15 years and 41.9 ± 6.4% at 20 years. On multivariate analysis the risk of valve failure was significantly higher in younger patients (P < 0.0001) and in those who underwent aortic root tailoring (P = 0.024). The freedom from endocarditis was 98.4 ± 0.9% at 10 years, 96.2 ± 1.6% at 15 years and 95.1 ± 1.9% at 20 years. Of the 249 patients, 218 had an isolated homograft AVR and were not anticoagulated. In this group there were two possible thromboembolic events.

Conclusion.

As well as the established haemodynamic benefits, this study has shown that homograft AVR with antibiotic-sterilised 4 °C stored homograft valves implanted in the subcoronary position, offers good long-term results.  相似文献   
969.
970.
The Gastric Bypass for Failed Bariatric Surgical Procedures   总被引:1,自引:0,他引:1  
Fox SR  Fox KS  Oh KH 《Obesity surgery》1996,6(2):145-150
Background: Revision of failed bariatric surgical procedures is a significant challenge for every bariatric surgeon. Methods: Evaluated are surgical difficulties, management problems and weight loss in patients with distal gastric bypass as a revisionary procedure. Eighty patients were followed up to 3 years; four were lost to follow-up. Mean age was 43; mean prebariatric surgery weight 134 kg; height 1.65 meters; body mass index 40.1; ideal body weight 62.7 kg; excess weight 70.5 kg; per cent excess weight 214%. A 250 cm stomach-to-ileocecal valve segment of small bowel was used, and the biopancreatic secretions were brought into the terminal ileum 100 cm from the ileocecal valve. Mean pouch size was 63 cc; length of hospital stay 5 days; operative blood loss 616 cc; operative time 130 min. Results: Intraoperative complications included three splenic injuries (without splenectomy). Early complications included one deep vein thrombosis, two marginal ulcers, one GI hemorrhage, one wound dehiscence, one pouch outlet obstruction and one pancreatitis. Late complications included: one death from protein malnutrition/ARDS; 21 hypoproteinemia; six protein malnutrition, and of these, three had hyperalimentation; three cholecystitis; 27 anemia; 22 incisional hernia; two staple-line disruption (reoperated); 26 low serum iron; 11 prolonged (> 6 months) diarrhea; three prolonged frequent vomiting; and two unrelated deaths (chronic myelogenous leukemia and amyotrophic lateral sclerosis). Mean excess weight loss was 83% at 12 months; 89% at 24 months; and 94% at 36 months. Conclusion: The distal gastric bypass is fraught with the operative and immediate post-operative complications experienced in any revisionary bariatric surgery. Distal gastric bypass is very effective in producing long-term weight loss. Nutritional problems are common but usually easily corrected. The most serious nutritional complication is protein malnutrition, which must be identified and corrected early. Success of this procedure is dependent upon patient compliance with proper nutrition and supplements, and regular office follow-up with monitoring of laboratory data. Patients who are noncompliant are at significant risk for complications.  相似文献   
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