Focusing of a Rydberg Positronium Beam with an Ellipsoidal Electrostatic Mirror.

Slow atoms in Rydberg states can exhibit specular reflection from a cylindrical surface upon which an azimuthally periodic potential is imposed. We have constructed a concave mirror of this type, in the shape of a truncated oblate ellipsoid of revolution, which has a focal length of (1.50±0.01) m measured optically. When placed near the center of a long vacuum pipe, this structure brings a beam of n=32 positronium (Ps) atoms to a focus on a position sensitive detector at a distance of (6.03±0.03) m from the Ps source. The intensity at the focus implies an overall reflection efficiency of ∼30%. The focal spot diameter (32±1) mm full width at half maximum is independent of the atoms' flight times from 20 to 60 µs, thus indicating that the mirror is achromatic to a good approximation. Mirrors based on this principle would be of use in a variety of experiments, allowing for improved collection efficiency and tailored transport or imaging of beams of slow Rydberg atoms and molecules.

Association between postoperative hypothermia and adverse outcome after coronary artery bypass surgery.

BACKGROUND: We examined the effect on outcome of mild hypothermia (< 36 degrees C) upon intensive care unit (ICU) admission on patient outcome after coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB). METHODS: We performed a retrospective database analysis of 5,701 isolated CABG patients requiring CPB, operated upon from January 1995 to June 1997. Patients were classified as either hypo- (< 36 degrees C) or normothermic (> or = 36 degrees C) upon ICU admission. ICU admission bladder core temperature (BCT) versus outcome was evaluated. Outcome measures included mortality, resource utilization (mechanical ventilation time, ICU and hospital length of stay, and postoperative packed red blood cell transfusion), and major morbidity (cardiac, renal, neurologic, or major infection). RESULTS: Overall, patients admitted to the ICU with BCT < 36 degrees C had a significantly greater mortality (p = 0.02), prolonged mechanical ventilation (p = 0.007), packed red blood cell transfusion (p = 0.001), ICU (p = 0.01), and hospital (p = 0.005) length of stay. CONCLUSIONS: BCT of less than 36 degrees C, upon ICU admission, has a significant association with adverse outcome after CABG with CPB. M An __ Tl QA_7_t-0

Long-term survival and functional capacity in cardiac surgery patients after prolonged intensive care.

OBJECTIVE: To determine whether hospital discharge alone represents a good outcome for patients who had prolonged intensive care after cardiac surgery by studying their postdischarge survival and functional outcome. The secondary objective is to estimate the proportion of intensive care unit (ICU) resources used by the long-stay (> or = 10 initial consecutive ICU days) patients and to identify preoperative patient characteristics that are associated with a prolonged ICU stay and hospital and long-term survival. DESIGN: Inception cohort study. SETTING: The Cleveland Clinic Foundation, a tertiary care, academic teaching institution. PATIENTS: Cardiac surgery patients with an initial ICU stay of 10 or more consecutive days. INTERVENTIONS: Data were collected daily during hospitalization on every adult who underwent coronary artery bypass graft and/or valve surgery at one institution in 1993. Discharged patients who spent >10 initial consecutive days in the ICU after surgery were contacted by telephone to determine vital status and functional capacity using the Duke Activity Status Index. Total ICU and total hospital direct costs were obtained for each patient. MEASUREMENTS AND MAIN RESULTS: The primary outcome measurements were ICU length of stay, hospital mortality, after-surgery and postdischarge mortality and functional capacity, and relative resource utilization. Of the 2,618 cardiac surgery patients who met the inclusion criteria, 142 (5.4%) had an initial ICU length of stay of 10 or more consecutive days. Of these, 47 (33.1%) died in the hospital. Ninety-four of the 95 discharged patients were followed up (median follow-up, 30.6 months), and 44 of the 94 (46.8%) died during the follow-up period. The median Duke Activity Status Index for the 50 survivors was 26 out of a possible 58.2. The 142 long-stay patients used 50% of the total ICU days and 48% of the total ICU direct cost for all 2,618 patients. CONCLUSIONS: Many survivors of prolonged intensive care die soon after hospital discharge and many longer term survivors have a poor functional state. Therefore, hospital discharge is an incomplete measure of outcome for these patients, and longer follow-up is more appropriate. The relatively small number of patients who require prolonged intensive care consumes a disproportionate amount of the total ICU and total hospital direct cost.

Physical mapping of the serotonin 5-HT(7) receptor gene (HTR7) to chromosome 10 and pseudogene (HTR7P) to chromosome 12, and testing of linkage disequilibrium between HTR7 and autistic disorder.

The gene encoding the serotonin 5-HT(7) receptor (HTR7) has been considered as a candidate locus in several neuropsychiatric disorders, based on pharmacological evidence and ligand-binding studies. After determining over 3 kb of previously unpublished sequence from introns 1 and 2 of HTR7, a single base (C/T) polymorphism in the second intron of HTR7 was found. Allele-specific PCR was used to genotype the HTR7 marker in 53 trios consisting of subjects with autistic disorder and both parents. Using the transmission disequilibrium test (TDT), no evidence of preferential transmission of either allele was found (TDT chi(2) = 0.252, p = 0.602). Sequence data obtained from both intron 1 and intron 2 of HTR7, and from the 5-HT(7) pseudogene (HTR7P), was used to confirm localization of HTR7 to 10q23 and HTR7P to 12p13 using radiation hybrid analyses.

Effect of calcitriol and pamidronate in multiple myeloma.

Addition of bisphosphonates to standard treatment of multiple myeloma (MM) decreases bone pain and skeletal events without influencing bone healing. Calcitriol, besides its established effects on bone remodeling and calcium metabolism, has both immunoregulatory and cell differentiating effects in vitro and in vivo. Moreover, low serum calcitriol has been reported in MM. We tested the effects of supportive treatment with calcitriol and pamidronate on bone disease in two stage-III-B MM patients with diffuse bone involvement, normal serum calcium, and low serum calcitriol. Complete blood counts, serum calcium, creatinine, quantitative serum and urine immunoglobulins, and biochemical indices of bone turnover, serum calcidiol, calcitriol, parathyroid hormone, skeletal radiographs, and bone mineral density by dual x-ray absorbtiometry were measured every 1-6 months for 16 months in the first patient and 7 months in the second patient. Both patients showed a dramatic improvement of MM activity and in bone disease documented by serial radiographs in the first patient and by increased bone mineral density (approximately 15%) in the second. The reduced serum calcitriol in both patients and the elevated parathyroid hormone observed in the first patient before treatment returned to normal. Supportive treatment with pamidronate does not induce bone healing in MM. Therefore, the results observed with the addition of calcitriol suggest that this hormone may have contributed to the apparent arrest of the progression of MM and caused stimulation of bone healing.

Predictors of outcome in cardiac surgical patients with prolonged intensive care stay.

OBJECTIVE: To determine the predictors of outcome in cardiac surgical patients with prolonged ICU stay. DESIGN: Inception cohort with retrospective chart review. SETTING: Adult cardiovascular ICU. PATIENTS: All patients admitted after cardiac surgery who stayed in ICU for at least 14 consecutive days. INTERVENTIONS: Collection of data, including preoperative demographics, comorbidity, routine laboratory testing, surgical procedure, duration of cardiopulmonary bypass and aortic cross-clamping, postoperative requirement for transfusion and intra-aortic balloon counterpulsation, and postoperative indexes of organ dysfunction 14 and 28 days after surgery. An organ failure score (OFS) was calculated for days 1, 14, and 28. OUTCOME MEASURES: Hospital mortality. RESULTS: One hundred forty-one of 324 (43.5%) ICU admissions lasting at least 14 days resulted in hospital mortality. Seventy-four of 166 (45%) ICU admissions lasting at least 28 days resulted in hospital mortality. Preoperative demographics, morbidity, and indexes of organ failure in the first 24 h after surgery were not predictive of hospital mortality. Indexes of organ failure predictive of hospital death at 14 days included requirement for epinephrine infusion, diminished Glasgow coma scale, requirement for dialysis, greater value of BUN, lower value of creatinine, greater value of bilirubin, greater value of arterial PCO2, lower platelet count, and lower value of serum albumin. After a 28-day stay in ICU, the indexes of organ failure predictive of hospital mortality included requirement for dopamine or norepinephrine infusions, diminished Glasgow coma score, greater value of bilirubin, greater value of arterial PCO2, lower value of serum albumin, and advanced age. The area under the receiver operating characteristic curve for the OFS on day 1 was 0.55+/-0.04 (p=0.12), on day 14 it was 0.75+/-0.03 (p<0.0001), and on day 28 it was 0.76+/-0.04 (p<0.0001). CONCLUSION: Preoperative health status and early organ failure were not predictive of late hospital mortality. The pattern of late organ failure associated with hospital mortality changed with time.

Destructive spondyloarthropathy of the cervical spine in patients with chronic renal failure.

STUDY DESIGN: Eleven patients with chronic renal failure and destructive spondyloarthropathy of the cervical spine were evaluated with plain radiographs, flexion-extension views, computed tomography myelogram, or magnetic resonance imaging to determine the results of surgical and nonsurgical treatment. OBJECTIVES: To determine if cervical spine fusion is an effective method of treatment for patients with chronic renal failure and destructive spondyloarthropathy. SUMMARY OF BACKGROUND DATA: Several reports have described the pathogenesis and appearance of this condition, but little has been reported about the orthopedic management of destructive spondyloarthropathy of the cervical spine. METHODS: Three patients had no spinal surgery, three patients had laminectomies alone, three patients had laminectomies with anterior fusions, and two patients had laminectomies with posterior fusions. Radiographs, computed tomography myelograms, and magnetic resonance images were evaluated to determine the results of treatment. Histologic examinations were performed in two patients. RESULTS: Patients with laminectomy alone had no improvement in pain or neurologic function (one died in the immediate postoperative period), one of three patients with anterior fusions had some improvement (one died in the immediate postoperative period), and both of those patients with posterior fusions improved, although both died within a year of surgery from unrelated causes. CONCLUSIONS: Even though the osteopenia present in patients with chronic renal failure tends to allow wire pull-out and makes internal fixation of the spine difficult, successful cervical spinal fusion can relieve pain and improve neurologic deficits in selected patients with chronic renal failure and destructive spondyloarthropathy, allowing them to remain more active for longer periods of time.

The risk of coronary artery surgery in women: a matched comparison using preoperative severity of illness scoring.

OBJECTIVE: To evaluate the effect of gender on outcomes of coronary artery bypass surgery using a weighted preoperative severity of illness scoring system. DESIGN: Retrospective database review. SETTING: Tertiary care teaching hospital. PARTICIPANTS: The patient population consisted of 2,800 consecutive coronary artery bypass graft (CABG) patients (658 women, 2,142 men), with or without concurrent procedures, operated on between January 1, 1993 and March 31, 1994. MEASUREMENTS AND MAIN RESULTS: Patients were stratified for severity of illness using a 13-element scoring system. The distribution of severity of illness scores and severity of illness-stratified morbidity, hospital mortality, and intensive care unit (ICU) length of stay were compared by chi-square and Fischer's exact test where appropriate. Median duration of intubation and median duration of ICU length of stay were examined by the median test. Female versus male unadjusted mortality (4.9% v 3.0%), total morbidity (15.0% v 9.2%), and average initial ICU length of stay (92.62% v 60.56 hours) were statistically different. Female patients also had significantly more of the following postoperative morbidities: central nervous system complications (focal neurologic deficits, patients > or = 65 years 3.20% v 1.54%; global neurologic deficits, patients > or = 65 years 2.75% v 1.25%), duration of perioperative ventilation that includes the intubation time in the operating room until extubation in the ICU (average = 77.36 hours v 49.20 hours; median = 21.87 v 20.26 hours), and average initial ICU length of stay (average = 92.62 hours v 60.56 hours; median = 42.33 hours v 27.91 hours). However, distribution of severity scores was also different. Women had significantly more preoperative risk factors (p < 0.05): age 65 to 74 years (45.1% v 36.6%), age > or = 75 years (21.3% v 11.9%), chronic obstructive pulmonary disease (10.8% v 6.4%), hematocrit less than 34% (21.9% v 5.5%), diabetes (34.8% v 21.8%), weight less than 65 kg (37.4% v 6.2%), and operative mitral valve insufficiency (9.6% v 6.0%). Stratified by severity, no statistically significant gender differences were found for mortality, morbidity, or ICU length of stay. CONCLUSIONS: Gender does not appear to be an independent risk factor for perioperative morbidity, mortality, or excessive ICU length of stay when patients are stratified by preoperative risk in this severity of illness scoring system.

Osteoarthrosis of the atlanto-axial joints. Long-term follow-up after treatment with arthrodesis.

We evaluated the results for fifteen patients in whom symptomatic osteoarthrosis of the atlanto-axial joints had been treated with an atlanto-axial or occipitocervical arthrodesis between 1973 and 1990. Thirteen patients had long-term follow-up (average duration, seven years and two months; range, four years and two months to nineteen years and two months). The two remaining patients had died: one, four days postoperatively, from a cardiopulmonary arrest, and the other, one year and eight months postoperatively, from complications related to bladder cancer. Preoperatively, all fifteen patients reported pain in the occipitocervical region that increased with any attempt at rotation of the neck and was unresponsive to immobilization with a collar and to analgesics. The average duration of the symptoms before the arthrodesis was three years. One patient had acute quadriparesis. All patients had radiographic evidence of oesteoarthrosis involving the lateral atlanto-axial articulations. Four patients had atlanto-axial instability with an average of five millimeters (range, three to ten millimeters) of motion at the anterior atlanto-odontoid interval. Six patients had an associated spontaneous subaxial fusion, which was secondary to osteoarthrosis in five; three of the five also had atlanto-axial instability. Fourteen patients were managed with a posterior arthrodesis and one, with an anterior transoral arthrodesis. The procedures were performed to relieve pain, to stabilize the atlanto-axial joints, and to restore neurological function. Of the fourteen patients who were followed, thirteen had a solid fusion and one had a stable pseudarthrosis. The patient who had quadriparesis recovered. At the latest follow-up evaluation, thirteen patients had an excellent result and one had a fair result as determined with use of a modification of the criteria of Robinson et al. There were no poor results. Atlanto-axial arthrodesis can effectively relieve occipitocervical pain and correct atlanto-axial instability secondary to osteoarthrosis.

Treatment of calcinosis with diltiazem.

OBJECTIVE: To test the hypothesis that the calcium antagonist diltiazem is effective in the treatment of calcinosis. METHODS: Diltiazem, 240-480 mg/day, was given to 4 patients with idiopathic or CREST-related (calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, telangiectasias) calcinosis for 1-12 years. Serial radiographs of the affected areas, using identical technique, and clinical evaluations were obtained. A fifth patient, who did not tolerate diltiazem, received verapamil, 120 mg/day for 18 months. RESULTS: All patients taking diltiazem had a reduction or disappearance of the calcific lesions, with striking clinical improvement. One patient's case was followed for 12 years. The response to diltiazem during the first 5 years of treatment has been previously reported in detail; however, over 7 years of additional treatment, there was further reduction of the lesions. One patient developed a large calcific lesion while receiving verapamil for hypertension, and after verapamil was replaced with diltiazem, there was a dramatic response. Verapamil was ineffective in the fifth patient, who did not tolerate diltiazem. CONCLUSION: Long-term treatment with diltiazem, but not verapamil, is effective in calcinosis.

Anterior decompression for late pain and paralysis after fractures of the thoracolumbar spine.

Anterior decompression of the thoracic and lumbar spine is indicated for patients with trauma, infection, or tumor that causes compression of the neural tissues, resulting in an incomplete neurologic deficit. The complication of chronic pain, with or without paralysis, that results from fractures with canal compromise has received little attention. This study involved 45 patients who had anterior decompression for chronic pain or paralysis at an average of 4.5 years after having thoracolumbar fractures. Pain was improved in 41 of 45 patients, with complete relief in 30 and partial relief in 11. In 25 patients with neurologic deficit, 21 noted improvement, 14 of which improved one or more grades of the Eismont classification. No patient had an increase in pain or loss of neurologic function. Complications were few. Anterior decompression of the thoracolumbar spine for chronic pain after thoracolumbar fractures is a safe and effective treatment for patients with this uncommon and difficult problem.

Spear tackler's spine. An entity precluding participation in tackle football and collision activities that expose the cervical spine to axial energy inputs.

We describe spear tackler's spine, a clinical entity that constitutes an absolute contraindication to participation in tackle football and other collision activities that expose the cervical spine to axial energy inputs. A subset of football players were identified who demonstrated: 1) developmental narrowing (stenosis) of the cervical canal; 2) persistent straightening or reversal of the normal cervical lordotic curve on erect lateral roentgenograms obtained in the neutral position; 3) concomitant preexisting posttraumatic roentgenographic abnormalities of the cervical spine; and 4) documentation of having employed spear tackling techniques. From data obtained by the National Football Head and Neck Injury Registry and the senior author's practice, 15 cases of spear tackler's spine were identified during 1987 to 1990. All 15 cases were evaluated because of complaints referable to the cervical spine or brachial plexus resulting from football injuries. Of these, 11 had complete neurologic recovery without permanent sequelae. Four cases resulted in permanent neurologic deficits: quadriplegia, 2; incomplete hemiplegia, 1; and residual long track signs, 1. Permanent neurologic injury occurred as the result of axial loading of a persistently straightened cervical spine from use of head-impact playing techniques. We suggest that individuals who possess the aforementioned characteristics of spear tackler's spine be precluded from participation in collision activities that expose the cervical spine to axial energy inputs.

Vertebral artery injury during anterior decompression of the cervical spine. A retrospective review of ten patients.

Ten patients who suffered iatrogenic injury to a vertebral artery during anterior cervical decompression were reviewed to assess the mechanisms of injury, their operative management, and the subsequent outcome. All had been undergoing a partial vertebral body resection for spondylitic radiculopathy or myelopathy (4), tumour (2), ossification of the posterior longitudinal ligament (1), nonunion of a fracture (2), or osteomyelitis (1). The use of an air drill had been responsible for most injuries. The final control of haemorrhage had been by tamponade (3), direct exposure and electrocoagulation (1), transosseous suture (2), open suture (1), or open placement of a haemostatic clip (3). Five patients had postoperative neurological deficits, but most of them resolved. We found direct arterial exposure and control to be safe, quick and reliable. Careful use of the air drill, particularly in pathologically weakened bone, as in infection or tumour, is essential. Arterial injury is best avoided by a thorough knowledge of the anatomical relationships of the artery, the spinal canal, and the vertebral body.

Postoperative cerebrospinal-fluid fistula associated with erosion of the dura. Findings after anterior resection of ossification of the posterior longitudinal ligament in the cervical spine.

Of twenty-two patients who had had anterior decompression of the spinal canal for ossification of the posterior longitudinal ligament and cervical myelopathy, seven had absence of the dura adjacent to the ossified part of the ligament. The spinal cord and nerve-roots were visible through this defect. Although the arachnoid membrane appeared to be intact and watertight in most patients, a cerebrospinal-fluid fistula developed postoperatively in five, and three had a second operation to repair the defect in the dura. On the basis of this experience, we recommend use of autogenous muscle or fascial dural patches, immediate lumbar subarachnoid shunting, and modification of the usual postoperative regimen, such as limitation of mechanical pulmonary ventilation to the shortest time that is safely possible and use of anti-emetic and antitussive medications to protect the remaining coverings of the spinal cord when the dura is found to be absent adjacent to an ossified portion of the posterior longitudinal ligament in the cervical spine.