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Biomedical subjects

J H Eichhorn

Publications and source records attributed to J H Eichhorn.

At least 19 recordsLinked to original sources
PubMed2003

Multiple hyperbaric oxygenation (HBO) expands the therapeutic window in acute spinal cord injury in rats.

Hyperbaric oxygenation (HBO) therapy has been reported to improve neurological recovery following spinal cord injury (SCI). In the present study, we examined whether multiple HBO expands the therapeutic window for acute SCI. Single HBO (2.8 ATA, 1 hour) treatment was used at 30 minutes, 3 hours, and 6 hours following SCI, and serial HBO treatment (once daily for 1 week) at 6 hours and 24 hours post-injury. Mild SCI was induced by adjusting the height for a weight drop insult (10 g) to 6.25 mm above the exposed spinal cord. The group of animals receiving a single HBO intervention beginning at 30 minutes and 3 hours, or serial HBO treatment starting at 6 hours following the injury had a significantly better neurological recovery than animals with SCI only. The results of this study demonstrate that multiple HBO expands the therapeutic window for acute SCI to 6 hours after injury, further that serial HBO administration is superior to single HBO therapy.

Acute Disease↗
PubMed2001

In vitro effects of hyperbaric oxygen on sickle cell morphology.

STUDY OBJECTIVE: To determine in vitro whether hyperbaric oxygen has any effect on the morphology of sickle cells. DESIGN: Prospective, in vitro, study, with each patient sample serving as its own control. SETTING: University medical center. PATIENTS: 10 children known to be homozygous for hemoglobin S. INTERVENTIONS: Blood samples were obtained from 10 children during routine visits to the University sickle cell clinic. Blood samples were exposed to room air to achieve maximal sickling. Each sample was divided into control and study aliquots, and the study portions placed in a research hyperbaric chamber with 100% oxygen at 3 atmospheres absolute pressure for 15 min. Then smears were prepared from all samples at regular intervals and examined by technicians in the sickle cell clinic who were blinded as to the details of this study. MEASUREMENTS: Percentages of normal cells, sickle cells and sickle forms were reported. Data were interpreted using t-tests. MAIN RESULTS: Hyperbaric oxygen appeared to have no effect on sickle cell morphology. Percentages of each cell type were unaffected by hyperbaric oxygen exposure. CONCLUSIONS: Hyperbaric oxygen appears to have no effect on the morphology of sickle cells in vitro. Other mechanisms may account for the beneficial clinical effects of hyperbaric oxygen in sickle cell crisis, although in vivo studies are warranted.

Anemia, Sickle Cell↗
PubMed2001

Neuroendocrine tumors of the genital tract.

Neuroendocrine tumors are more common in the female than male genital tract; most are uterine small cell carcinomas or ovarian carcinoids. Primary ovarian carcinoids are divided into insular, trabecular, strumal, and mucinous types; most are benign. Carcinoids metastatic to the ovary are more aggressive; most arise in the gastrointestinal tract. Scattered neuroendocrine cells are seen in a variety of ovarian surface epithelial tumors; sporadic mucinous cystic tumors with neuroendocrine cells have been associated with Zollinger-Ellison syndrome. Frank neuroendocrine carcinomas in the ovary include small cell carcinoma and large cell neuroendocrine carcinoma, each with a poor prognosis and often associated with a conventional surface epithelial tumor Such carcinomas also occur in the endometrium and cervix. Uterine carcinoids are rare if strict criteria are applied. Small cell neuroendocrine carcinomas also occur rarely in the vagina and vulva. Most male genital tract neuroendocrine tumors are prostatic small cell carcinomas or testicular carcinoids. Extragonadal carcinoids of the male genital tract are rare. Testicular carcinoids should be distinguishedfrom metastatic tumors. It is important to distinguish prostatic small cell carcinoma from poorly differentiated adenocarcinoma with small cells. Small cell neuroendocrine carcinomas also occur rarely in the scrotum, penis, and penile urethra.

Adolescent↗
PubMed2000

Falsely elevated bispectral index during deep hypothermic circulatory arrest.

A 2-month-old infant underwent repair of a ventricular septal defect under deep hypothermic circulatory arrest. Bispectral index and EEG suppression ratio were evaluated using an Aspect BIS monitor. Erroneous readings from the monitor could have led to a potentially dangerous alteration in surgical and anaesthetic management.

Electroencephalography↗
PubMed2000

Preoperative exposure to calcium channel blockers suggests increased blood product use following cardiac surgery.

PURPOSE: In this study the authors reviewed the medical records of a random sample of patients undergoing coronary artery bypass grafting (CABG) during the preceding ten years at University Medical Center. The purpose of this study was to evaluate the impact of exposure to calcium channel blockers (CCB's) on blood product use following cardiopulmonary bypass (CPB). METHODS DESIGN: Retrospective medical record review. SETTING: University hospital. PARTICIPANTS: 527 patients undergoing CABG or re-do CABG. INTERVENTIONS: The medical records of approximately 50% of patients undergoing CABG or re-do CABG at University Medical Center between 1988 and 1998 were randomly selected by the medical records librarian for review. Preoperative medications, bypass time and temperature, and blood product use were recorded. RESULTS: Of the 527 patients studied, 309 (59%) had no exposure to CCB's. 218 (41%) were on CCB's at the time of admission. Patients who were on CCB's had an average 12.5 (+/- 1.0) blood product units transfused following bypass whereas those not on CCB's had an average 8.7 (+/- 0.6) units transfused (p < 0.001). Use of packed red blood cells (p < 0.001), fresh frozen plasma (p = 0.018) and platelets (p = 0.023) were each individually significantly increased. CONCLUSIONS: In this study, it appeared that patients exposed to CCB's before cardiac revascularization received significantly more blood products than those who were not exposed to CCB's. Because of the limitations imposed by retrospective studies, further prospective studies are warranted to define the clinical significance of CCB use in the perioperative period.

Blood Component Transfusion↗
PubMed1999

Interaction of an implanted pacemaker with a transesophageal atrial pacemaker: report of a case.

We report an interaction of a transesophageal atrial pacemaker (TAP) with a permanently implanted pacemaker in a cardiac patient who had undergone ablative therapy for atrial tachyarrhythmia 5 years earlier. The patient's permanent A-V pacemaker was completely inhibited by the TAP, and there was loss of ventricular contractions and blood pressure. The patient required epicardial A-V pacing to overcome the programmed heart rate of 76 bpm. We describe alternative methods to epicardial pacing. We also recommend close inspection of the chest radiograph, which often can reveal the serial numbers of the implanted pacemaker, as a means of identifying the device's functions and programming.

Blood Pressure↗
PubMed1999

Ovarian serous borderline tumors with micropapillary and cribriform patterns: a study of 40 cases and comparison with 44 cases without these patterns.

A group of investigators have proposed that the presence of micropapillary or cribriform patterns within ovarian serous tumors diagnosed as borderline according to World Health Organization (WHO) criteria identifies a subset of these neoplasms that are apt to be associated with invasive peritoneal implants and therefore should be designated as "micropapillary carcinoma." The authors of the current article identified 40 serous borderline tumors that showed one or both of these patterns, using the earlier investigators' published criteria for so-called micropapillary carcinoma, and compared them with 44 tumors that lacked these patterns (controls). Twenty-six patients with micropapillary tumors were aged 21 to 76 years (mean 38); 11 with cribriform tumors were aged 34 to 79 years (mean 60); and 3 with tumors having both patterns were aged 21 to 58 years (mean 38); the control patients were aged 22 to 83 years (mean 54). An advanced stage, bilaterality, and ovarian surface growth were features of the "micropapillary" tumors more often than of the control tumors. Except for a postoperative death related to sepsis, all 11 patients with Stage I tumors with either or both patterns who were followed until their death, or for at least 5 years (mean 7.9 years), survived without evidence of disease; a twelfth patient had a recent removal of recurrent pelvic tumor at 2.8 years and was alive at 3.3 years. Six of the eight patients with Stage II or III tumors with either or both patterns who were followed for at least 5 years (mean 7.5 years) survived disease-free. No deaths from tumor or progressive recurrences occurred in 27 control cases with 5-14 (mean 7.9) years of follow-up data. The two tumor-related deaths in the entire series, one from a micropapillary tumor and one from a cribriform tumor, occurred in patients who had Stage III tumors with invasive peritoneal implants. No patient with "micropapillary" tumors and noninvasive implants had progressive disease. Two women with "micropapillary" tumors and two control subjects had stable recurrent tumor or a newly developed tumor in a contralateral ovary that had been spared during the initial operation. Our findings confirm those of previous investigators that noninvasive serous tumors with a micropapillary or cribriform pattern or both patterns may be accompanied by invasive peritoneal implants more often than tumors without such patterns and that in such cases the disease is likely to be progressive and fatal. Since so-called micropapillary carcinomas lack obvious stromal invasion within the ovary, and their prognosis when they spread to the peritoneum is much closer to that associated with typical Stage II and III serous borderline tumors than to that associated with similarly staged serous carcinomas, the authors believe that this newly described category of tumors should remain as a subset within the borderline category, with a notation that their prognosis is poor if they are associated with invasive peritoneal implants.

Adult↗
PubMed1998

Visceral analgesic tolerance to intrathecal butorphanol in rats.

PURPOSE: Recent experimental data suggest that intrathecal (it) kappa-opioid agonists produce profound visceral analgesia. This study investigated the development of visceral analgesic tolerance to it butorphanol, a potent kappa-agonist that has fewer side effects than commonly used it opioids. Understanding of this tolerance could make it butorphanol more effective in treating chronic visceral pain. METHODS: This was a randomized, controlled animal study involving 80 Sprague-Dawley rats. Rats implanted with lumbar it catheters were infused either with it saline or butorphanol (52 nmol.hr-1) for 96 hr. Six hours afterwards, each rat was challenged once with one of the differing it butorphanol doses to construct dose-response curves. Visceral analgesia was evaluated by the abdominal writhing responses to the acetic acid injected intraperitoneally. The time of the first writhe and the total number of writhes were recorded. RESULTS: For both the saline- and butorphanol-infused groups, a higher challenge dose of it butorphanol produced longer time for the first writhe to occur (P < 0.01, one-way ANOVA), and fewer writhes occurring within 30 min (P < 0.01, one-way ANOVA). However, the dose response curves of the butorphanol-infused groups were shifted rightward (P < 0.001, partial F test). CONCLUSION: The challenge doses of it butorphanol produced dose-dependent visceral analgesia in both the saline- and butorphanol-infused groups, confirming its efficacy. The butorphanol-infused groups showed dose-response shifts, demonstrating the development of tolerance to this visceral analgesia.

Acetic Acid↗
PubMed1998

Pulse oximetry monitoring and late postoperative hypoxemia on the general care floor.

Hypoxemia has long been recognized as a risk to patients in the operating room and postanesthesia care unit, and hemoglobin oxygen saturation (HbO2) monitoring with pulse oximetry has become a standard of care in these areas. There is growing evidence, however, suggesting that later postoperative hypoxemia also may play a role in organ dysfunction leading to morbidity and mortality. Economic pressures to move patients earlier from expensive postanesthesia recovery and intensive care areas to the general care floor -- where nurse-to-patient ratios are lower and lines of sight and sound may be impaired by walls and curtains -- may lead to inadequate surveillance of at-risk patients. These patient-management trends underscore the importance of improved monitoring of respiratory status on the general care floor. In this environment, telemetric pulse oximetry monitoring may represent a cost-effective approach to maximizing quality of care while enhancing risk management. This review discusses late postoperative hypoxemia and identifies areas for further investigation.

Anesthesia Recovery Period↗
PubMed1997

A comparison of two different bronchial cuff designs and four different bronchial cuff inflation methods.

OBJECTIVE: To compare directly measured pressures at the cuff/trachea interface that are associated with two different bronchial cuff designs and four different methods of bronchial cuff inflation suggested for use with one-lung ventilation. DESIGN: In vitro study. SETTING: Experimental laboratory in a university-affiliated hospital. INTERVENTIONS: The bronchial cuffs of two different endotracheal tubes were inflated using one of four different methods of determining the cuff volume and pressure necessary to "just seal" the bronchus and obtain lung separation; positive-pressure test, negative-pressure test, CO2 analysis, and a new test using an anesthesia ventilator. When each method predicted the "just-seal" state, the pressure at the cuff/bronchus interface as well as cuff inflation pressure and volume were recorded. MEASUREMENTS AND MAIN RESULTS: Although the new test was incompatible with the bronchial blocker, the other three tests all accurately predicted lung separation with the Univent, with no significant differences in pressures exerted on the trachea. However, when used with the double-lumen tube, the new test produced significantly lower measured parameters than the other inflation methods. CO2 analysis did not reliably predict bronchial seal with the double-lumen tube. CONCLUSIONS: To achieve lung separation with the lowest pressure on the trachea, the new test is the most appropriate method for use with the double-lumen tube; however, the negative-pressure test appeared to be the easiest and fastest method for use with the bronchial blocker. Although the bronchial blocker was associated with lower pressures transmitted from the cuff to the trachea, the in vitro model cannot predict which bronchial cuff design would be superior in vivo.

Adult↗
PubMed1997

Decreased paralysis and better motor coordination with microspinal versus PE10 intrathecal catheters in pain study rats.

We compared the standard PE10 catheter to a smaller microspinal catheter for intrathecal (IT) catheterization in rats. The PE10 or microspinal catheter was implanted in the lumbar subarachnoid space through the atlantooccipital membrane in rats (21 each group). Surviving rats without paralysis were tested on a rota-rod treadmill for motor function on Postoperative Days (POD) 3-6. Different doses of IT butorphanol were injected to demonstrate the functionality of the catheters by measuring tail-flick antinociception. Methylene blue was injected IT immediately before the spinal necropsy in each rat to identify the catheter tip location. For PE10 and microspinal catheters, the immediate death rate after the catheter implantation was 4 of 21 and 3 of 21 (no significant difference); paralysis rate was 8 of 21 and 2 of 21 (P < 0.05), and motor coordination recovery on POD6 was 67% and 91% (P < 0.01), respectively. Rats in both groups showed a dose-dependent response to IT butorphanol. Intrathecal methylene blue stained the lumbar spinal cord but not the surrounding tissue in both groups. Therefore, the microspinal catheter is better than the PE10 for IT catheterization in rats because it causes less paralysis and provides faster recovery of motor function.

Animals↗
PubMed1996

Histologic transformation of benign endometriosis to early epithelial ovarian cancer.

Between 1975 and 1990, 79 patients with Stage I epithelial ovarian cancer were treated at Massachusetts General Hospital. Patients were identified from the tumor registry and medical records were retrospectively reviewed. Pathological slides were evaluated for the presence of endometriosis, specifically looking for malignancy arising in endometriosis. Evidence of endometriosis was found in 22 of the 79 cases (28%). In the 23 cases of endometrioid histology, 9 cases (39%) were associated with endometriosis and, in the 17 cases of clear cell tumors, 7 (41%) were associated with endometriosis. All 8 cases of mixed histology had clear cell and/or endometrioid components and 4 cases (50%) were associated with endometriosis. Endometrioid adenocarcinoma accounted for 41% of the tumors associated with endometriosis, clear cell carcinoma 31%, mixed (endometrioid and/or clear cell types) 18%, and other types 9%. Among the 22 patients with associated endometriosis, we found 7 carcinomas (32%) arising in endometriosis. In these 7 cases a spectrum of benign and atypical endometriosis with a transition to clear cell or endometrioid adenocarcinoma were identified. These premalignant changes were characterized by cytologic atypia and architectural proliferation. Endometriosis was frequently encountered among patients with Stage I epithelial ovarian cancer of endometrioid and clear cell histologies. Endometriosis may play a role in the pathogenesis of some early stage malignant ovarian epithelial neoplasms.

Adenocarcinoma, Clear Cell↗
PubMed1996

Sertoliform endometrial adenocarcinoma: a study of four cases.

We studied four endometrial carcinomas with a conspicuous component that resembled patterns in Sertoli cell tumors. The patients presented at age 44-83 years (mean 65 years), with abnormal or postmenopausal vaginal bleeding in three and abnormal cervical cytology in one. All were multiparous, moderately to markedly obese, and hypertensive, and three patients had non-insulin-dependent diabetes mellitus. One tumor was suspected to be an endometrial stromal sarcoma with sex-cord-like differentiation on biopsy. Gross examination of the hysterectomy and bilateral salpingo-oophorectomy specimens showed solid polypoid endometrial tumors in each case. Light microscopic examination showed three to be superficially invasive of the myometrium and one to be confined to the endometrium; none of the tumors showed the tongue-like pattern of myoinvasion or the angiolymphatic invasion characteristic of low-grade endometrial stromal sarcomas. The sertoliform component, which predominated in one case and was only focal in the three others, was composed of uniform small hollow tubules lined by columnar cells with apical cytoplasm and of compact slender cords. The tubules and cords were often present between benign-appearing or carcinomatous glands. In the case with predominate sertoliform areas, the lesional cells had clear cytoplasm suggesting a lipid-rich variant; special stains of this case demonstrated cytoplasmic glycogen but no fat. In none of the cases was cytoplasmic mucin, argyrophil granules, or argentaffinity demonstrated. The nonsertoliform areas of the tumors consisted of typical endometrioid adenocarcinoma; concurrent endometrial hyperplasia was also present in each case. Squamous differentiation and minor foci of anaplastic carcinoma with bizarre tumor giant cells were present in three tumors. Immunoperoxidase stains showed staining for two or more markers of epithelial or glandular differentiation in the sertoliform areas in all cases (keratin, epithelial membrane antigen, carcinoembryonic antigen, CA125, Tag72), with focal expression of vimentin in all cases. In none of the cases was desmin or actin staining observed. The evidence indicates that tumors in this series are variants of endometrioid adenocarcinoma and are distinct from uterine tumors resembling ovarian sex-cord tumors and stromal sarcomas with sex-cord-like differentiation.

Adenocarcinoma↗
PubMed1996

Endometrioid ciliated-cell tumors of the ovary: a report of five cases.

Five patients with ovarian endometrioid tumors composed predominantly of ciliated cells are reported; two patients had bilateral neoplasms. Two unilateral, predominantly cystic ciliated-cell tumors from women in their 40s were associated with endometriosis: one was borderline and arose in an endometriotic cyst; the other was borderline with foci of carcinoma and was associated with ipsilateral ovarian and peritoneal endometriosis. Five predominantly adenofibromatous tumors in the three other women, all postmenopausal, were not associated with endometriosis. One woman with a borderline ciliated-cell adenofibroma had had a prior contralateral adnexectomy, another with a borderline ciliated-cell adenofibroma had a contralateral ciliated-cell adenofibroma, and the third woman had a ciliated-cell adenocarcinoma and a contralateral borderline ciliated-cell adenofibroma. In two of the latter three patients the fallopian tubes contained foci of ciliated-cell hyperplasia. All five ciliated-cell malignant tumors were stage I, were treated by operation alone, and had not recurred 21 to 64 (mean 39) months postoperatively. Ciliated-cell tumors of the ovary should be distinguished from serous and mixed serous and endometrioid cancers because of different pathological and possibly different clinical features. Criteria for separating endometrioid ciliated-cell tumors into benign, borderline, and malignant categories are presented; whether any of these neoplasms behaves in a clinically aggressive fashion has yet to be determined.

Adenofibroma↗
PubMed1996

Ovarian neuroendocrine carcinomas of non-small-cell type associated with surface epithelial adenocarcinomas. A study of five cases and review of the literature.

Five primary ovarian carcinomas composed of a high-grade neuroendocrine tumor of non-small-cell type and a surface-epithelial-stromal tumor are reported. The five tumors presented in women aged 36 to 77 (mean, 57) years with abdominal distension or a palpable mass in three cases, right lower quadrant pain with tenderness and fever in one case, and a cervicovaginal smear showing a high estrogen effect in one postmenopausal patient. The tumors were unilateral, 9 to 30 (mean, 16) cm in greatest dimension, and had solid and cystic components. Three tumors were stage I; one, stage II; and one, stage III. Two patients who received chemotherapy died of tumor 8 and 36 months postoperatively, another who refused chemotherapy but later received radiation died of tumor after 19 months, a fourth was lost to follow-up, and a fifth was treated recently. Microscopically, the neuroendocrine components of all the tumors were composed predominantly of sheets, closely packed islands, cords, and trabeculae of epithelial cells with little intervening stroma. The tumor cells in the neuroendocrine areas were medium-sized to large compared with the cells of small cell carcinoma, and they contained scanty to moderate amounts of cytoplasm and hyperchromatic nuclei with coarse chromatin clumping in three cases and abundant cytoplasm and vesicular nuclei with single, large eosinophilic nucleoli in the other two. In all the cases, areas of necrosis and single-cell necrosis were extensive, and mitotic figures were abundant. Positive argyrophil and argentaffin reactions were observed in occasional to many cells in all cases. The glandular components of the tumors were grade 1/3 endometrioid adenocarcinoma (one case), grade 2/3 mucinous adenocarcinoma (2 cases), and mucinous borderline tumor with small foci of mucinous adenocarcinoma (two cases). Numerous enterochromaffin cells were identified in hematoxylin and eosin sections of the borderline mucinous components of two tumors; occasional nonargentaffin argyrophilic cells were present in the endometrioid and mucinous carcinoma components. Luteinized stromal cells were present focally in two cases, including the case in which there was evidence of a high estrogen level. Immunohistochemical studies in five cases showed staining of most cells in the solid components for cytokeratin and chromogranin A and some to most cells for serotonin and neuron-specific enolase. Neuropeptides that were detected in the solid component of one or more of the cases included vasoactive intestinal peptide, somatostatin, gastrin, and glucagon; negative results were obtained for pancreatic polypeptide and insulin. Flow cytometry in four tumors revealed that the neuroendocrine component was aneuploid in two, suspicious for aneuploidy in one, and diploid in one. Tumors of the type described are distinct pathologically from primary ovarian carcinoid tumors and small cell carcinoma of pulmonary type. Although experience with this type of tumor is limited, the prognosis appears to be poor.

Adenocarcinoma↗