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Neonatal high-frequency jet ventilation: four years' experience 总被引:2,自引:0,他引:2
S J Boros M C Mammel J M Coleman P K Lewallen M J Gordon D R Bing J P Ophoven 《Pediatrics》1985,75(4):657-663
During a 4-year period, 34 neonates were treated with high-frequency jet ventilation (HFJV) using two different HFJV systems. Twenty-three of the neonates had severe pulmonary air leaks, five had congenital left-sided diaphragmatic hernias, and six had end-stage respiratory failure without pulmonary air leaks. The two HFJV systems performed similarly in all pathologic conditions. Following HFJV, arterial blood gas values improved in 28 of the 34 patients (82%). Eleven patients (32%) ultimately survived. Of 23 patients with pulmonary air leaks, 17 (74%) improved, nine (39%) survived. One infant with diaphragmatic hernia and one with end-stage respiratory failure survived. Ten of 12 patients (85%) who died following eight or more hours of HFJV had significant tracheal histopathology in the region of the endotracheal tube tip. The lesions ranged from moderate erythema to severe necrotizing tracheobronchitis with total tracheal obstruction. HFJV can be useful in the treatment of severe pulmonary air leaks in neonates and may prove useful in the treatment of congenital diaphragmatic hernias. However, HFJV produces inflammatory injuries in the proximal trachea. More clinical and laboratory studies are needed to define the relative risks and benefits of this new therapy. 相似文献
104.
Complications of spinal cord arteriography: prospective assessment of risk for diagnostic procedures
Forbes G; Nichols DA; Jack CR Jr; Ilstrup DM; Kispert DB; Piepgras DG; Wiebers DO; Earnest F th; Axley PL 《Radiology》1988,169(2):479-484
A prospective study was done of complications associated with 134 consecutive diagnostic spinal cord arteriograms in 96 patients (63 men and 33 women aged 17-78 years). Patients were examined for either arteriovenous malformation (n = 88) or tumor (n = 8), as indicated by myelography. Among the complications, 11 (8.2%) were local, five (3.7%) were systemic nonneurologic, and three (2.2%) were neurologic (two were associated with full recovery in less than 24 hours, and one was associated with full recovery in less than 1 week). No specific clinical or technical factors were significantly associated with the development of neurologic complications. Details of the clinical profile, angiographic technique, and pathologic findings for each patient were recorded and analyzed with respect to the potential risk for arteriographic complications. Diagnostic spinal cord arteriography had an acceptable risk within the range of other neuroangiographic diagnostic procedures. 相似文献
105.
Spacing of cytochrome oxidase blobs in visual cortex of normal and strabismic monkeys 总被引:3,自引:3,他引:0
Murphy KM; Jones DG; Fenstemaker SB; Pegado VD; Kiorpes L; Movshon JA 《Cerebral cortex (New York, N.Y. : 1991)》1998,8(3):237-244
Some models of visual cortical development are based on the assumption that
the tangential organization of V1 is not determined prior to visual
experience. In these models, correlated binocular activity is a key element
in the formation of visual cortical columns, and when the degree of
interocular correlation is reduced the models predict an increase in column
spacing. To examine this prediction we measured the spacing of columns, as
defined by cytochrome oxidase (CO) blobs, in the visual cortex of monkeys
whose binocular vision was either normal or disrupted by a strabismus. The
spatial distribution of blobs was examined in seven normal and five
strabismic macaques. Tangential sections through the upper layers of the
visual cortex were stained to reveal the two-dimensional (2D) pattern of CO
blobs. Each blob was localized and their center-to-center spacing, packing
arrangement and density were calculated using 2D nearest-neighbor spatial
analyses. The mean center-to-center spacing of blobs (590 microm for
normally reared and 598 microm for strabismic macaques) and the mean
density of blobs (3.67 blobs/mm2 for normally reared and 3.45 blobs/mm2 for
strabismic macaques) were not significantly different. In addition, the 2D
packing arrangement of the blobs was not affected by strabismus. While it
is clear that neural activity plays a key role in the elaboration and
refinement of ocular dominance cortical modules, we conclude that it does
not determine the spatial period of the pattern of CO blobs. This suggests
that aspects of the neural circuitry underlying the columnar architecture
of the visual cortex are established prenatally and its fundamental
periodicity is not modifiable by experience.
相似文献
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El Toukhy E Lewallen S Courtright P 《Ophthalmic plastic and reconstructive surgery》2006,22(2):109-112
PURPOSE: To determine risk factors for early failure of the bilamellar tarsal rotation procedure in trachomatous trichiasis. METHODS: This was a prospective study in which the bilamellar tarsal rotation procedure was performed on 638 eyelids in Menofiya governorate in Egypt over a 4-year period. An analysis was performed to determine the incidence of early surgical failure (defined as one or more lashes touching the eyeball) after 8 weeks and to determine the risk factors for these failures. RESULTS: Follow-up data were available on 599 eyes at 8 to 10 weeks after surgery. Considering all eyes, failure (one or more lashes touching the eyeball) was noted in 98 eyes (16.4%). Failure was associated with preoperative corneal staining (RR, 3.27; 95% CI, 2.34 to 4.57), preoperative corneal opacity (RR, 1.64; 95% CI, 1.15 to 2.34), the use of silk sutures (RR, 54.82; 95% CI, 7.72 to 389.4), and the use of 4 or more sutures (RR, 1.24; 95% CI, 1.04 to 1.48). CONCLUSIONS: The finding that specific sutures or needles was associated with early failure of the bilamellar tarsal plate rotation procedure for trachomatous trichiasis was unexpected and deserves further study. 相似文献
109.
Haidukewych GJ Jacofsky DJ Hanssen AD Lewallen DG 《The Journal of bone and joint surgery. American volume》2006,88(9):1952-1956
BACKGROUND: The intraoperative occurrence of an acetabular fracture is a rare complication of primary total hip arthroplasty. Previous reports have lacked a sufficiently large number of subjects to allow for an analysis of the causes and appropriate treatment of this problem. METHODS: Between 1990 and 2000, 7121 primary total hip arthroplasties were performed at our institution. We retrospectively reviewed the records in our Total Joint Registry and found that twenty-one patients (twenty-one hips) had sustained an intraoperative acetabular fracture. Nineteen of these patients (nineteen hips) had been followed until revision or for a minimum of two years (mean duration of follow-up, forty-four months). We evaluated the anatomic location, cause, treatment, and outcome of the fractures. Acetabular component designs were categorized as modular, nonmodular (monoblock), true hemispherical, or elliptical, and then each design was analyzed for fracture risk. RESULTS: No fractures occurred in association with cemented acetabular components. The fracture rate associated with uncemented components was 0.4%. In seventeen hips, the acetabular component was judged to be stable despite the detection of a fracture and the cup was retained. In four hips, the original cup was not stable and therefore was replaced with a design that allowed for supplemental screw fixation. All fractures united, and all cups demonstrated osseous ingrowth at the time of the most recent follow-up. Elliptical monoblock cups were associated with a significantly higher fracture rate than were elliptical modular cups (p < 0.0001) and hemispherical modular cups (p < 0.0001). There was no significant difference between elliptical modular and hemispherical modular components with regard to the fracture rate. CONCLUSIONS: Acetabular fracture during primary total hip arthroplasty is a rare complication of acetabular fixation without cement. In the present series, retention of a stable cup was associated with uneventful osseous ingrowth and excellent early-term outcomes. We found a high rate of fracture in association with the use of monoblock elliptical components. LEVEL OF EVIDENCE: Therapeutic Level III. 相似文献
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