Pooled preventable death rates in trauma patients Kwon, A. M.; Garbett, N. C.; Kloecker, G. H.
European journal of trauma and emergency surgery (Munich : 2007),
06/2014, Letnik:
40, Številka:
3
Journal Article
Recenzirano
Purpose
To estimate the pooled PDRs (preventable death rates) with articles being published since 1990, and compare the differences of PDRs over time and according to the evaluation approaches to ...determine preventable deaths.
Methods
Articles concerning preventable deaths of trauma patients published between 1990 and 2013 were systematically reviewed, and the pooled PDRs with 95 % confidence intervals were estimated using meta-analysis. It was also observed whether the PDRs differed over time and according to the evaluation approaches employed for determining preventable deaths.
Results
Twenty seven articles were identified through bibliographic searches using PUBMED with the keywords of ‘preventable deaths’, ‘the cause of deaths’ and ‘trauma’. Mean ages of the trauma patients in the selected articles ranged from 32.9 to 58 years old and 72 % were male on average. The pooled PDR was estimated as 0.20 with 95 % CI (0.16, 0.25) with a
p
-value of 0.0001, and the differences of PDRs over time and according to the employed approaches were not statistically significant with
p
-values of 0.06 and 0.99, respectively. However, PDRs determined by statistical approaches alone showed greater dispersion in comparison with the ‘panel review approach’.
Conclusions
This article provided some insights about the trauma care system by computing the pooled estimate of PDRs over the past 23 years as an indicator. The pooled PDR was estimated as approximately 20 %, with no statistical significance of differences in PDRs over time or by the evaluation methods employed. That left us still room for improvement in trauma care system despite our efforts to reduce PDRs. In addition, when ‘statistical approaches’ are applied alone to estimate PDRs, we recommend that statistical methods should be applied with caution when the characteristics of trauma patients are heterogeneous. The optimal approach might be to combine both statistical and panel review approaches instead of employing a single approach.
The analysis in this paper concerns the performance of smart antenna algorithms when used in code-division multiple access (CDMA) wireless communication systems. Complex pseudonoise (PN) spreading, ...despreading, and pilot-aided channel estimates in the cdma2000 reverse link are some of major characteristics that are different from those in the IS-95 CDMA systems. These different features are included in our analysis. Four computationally efficient smart antenna algorithms are introduced: 1) smart antenna based on maximum output power criteria without Lagrange multiplier; 2) smart antenna based on maximum signal-to-interference-plus-noise output power ratio (SINR) criteria with eigenvector solution; 3) smart antenna based on maximum SINR output criteria without eigenvector solution; 4) more simplified smart antenna based on maximum SINR output criteria without eigenvector solution. Algorithms (1) and (4) require only 4M computational instruction cycles per snapshot where M is the number of antenna array elements. Algorithms (2) and (3) require M/sup 2/ and (4M+2M/sup 2/) operations per snapshot, respectively. These computational loads are significantly smaller than those of typical eigenvalue decomposition blind detection approaches. Bit error rates (BERs) resulting from these algorithms are evaluated through simulation. A double spike power delay profile with equal or unequal power is used. Also, a cluster of interfering users and scattered interference users are considered. For BER comparisons, antenna diversity using equal gain combining is also analyzed. The four smart antenna algorithms show significant capacity improvement compared to the antenna array diversity using equal gain combining under the double spike power delay profile with equal power and scattered interference environments.
This paper considers synchronization problem of a delayed complex dynamical network. For the problem, the virtual target node is chosen as one of nodes in the complex network. It should be pointed ...out that only one connection is needed between a real target node and a virtual target node instead of
N
connections. Moreover, the proposed synchronization scheme does not require additional conditions for coupling matrix unlike the existing works. Based on Lyapunov stability theory, a new design criterion for an adaptive feedback controller to achieving synchronization between the real target node and all nodes of the delayed complex network is developed. Finally, the proposed method is applied to a numerical example in order to show the effectiveness of our results.
This paper presents a predictive synchronization method for discrete-time chaotic Lur’e systems with input constraints by using time-varying delayed feedback control. Based on the model predictive ...control scheme, a delay-dependent stabilization criterion is derived for the synchronization of chaotic systems that is represented by Lur’e systems with input constraints. By constructing a suitable Lyapunov–Krasovskii functional and combining with a reciprocally convex combination technique, a delay-dependent stabilization condition for synchronization is obtained via linear matrix inequality (LMI) formulation. The control inputs are obtained by solving a min-max problem subject to cost monotonicity, which is expressed in terms of LMIs. The effectiveness of the proposed method will be verified throughout a numerical example.
The frequency and extent of epidural fluid collection after percutaneous endoscopic lumbar discectomy (PELD) have not been previously described. The purpose of this study was to evaluate the ...significance of epidural fluid collection after PELD.
From March 2008 to November 2015, immediate postoperative magnetic resonance imaging (MRI) of 464 consecutive patients, comprising 284 men and 180 women, were obtained after PELD. The mean age of the patients at the time of admission was 43.1 years (range, 18–81 years). We also performed 24-hour follow-up MRIs after PELD in 35 patients to evaluate the morphologic changes on epidural fluid collection and to identify whether the collection was due to saline accumulation or cerebrospinal fluid leak.
The level of disc herniation was at L4–5, L5–S1, L3–4, and L2–3 in 245 (52.8%), 173 (37.3%), 37 (8.0%), and 9 (1.9%) patients, respectively. Of 464 patients, 418 (90.1%) had abnormal epidural fluid collection, 404 (87.1%) patients had ventral epidural fluid collection, 393 (84.7%) patients had dorsal epidural fluid collection, and 10 patients had epidural hematoma as per immediate postoperative MRI. According to the 24-hour follow-up MRI findings, 30 patients had epidural fluid collection; the epidural fluid collection in 28 patients (93.3%) resolved with time, and a minimal amount of fluid remained in 2 patients, but the lesion size decreased compared with that on the previous day.
Epidural fluid collection usually occurs after percutaneous endoscopic discectomy, which is mainly due to saline accumulation and typically resolves with time, without treatment or complications.
•Epidural fluid collection usually occurs after percutaneous endoscopic lumbar discectomy (PELD).•Epidural fluid collection after PELD is more frequent in the central to subarticular disc herniation.•Epidural fluid collection was due to saline accumulation during PELD.•Epidural fluid collection after PELD typically resolves with time, without specific treatment or complications.
Abstract Purpose The study sought to synthesize anionic peptide-conjugated tissue plasminogen activator (tPA) for its targeted/triggered delivery, where tPA's activity would be masked in the ...circulation and regenerated at the thrombus site by a commonly used anticoagulant, heparin, to minimize tPA associated bleeding complications. Methods tPA was conjugated to Polyglutamate, and the activity of oligoanion-modified tPA was tested by fibrinolytic assay. Separately human serum albumin (HSA) was conjugated to protamine and the formation of its electrostatic complex with anionic peptide was monitored by Förster Resonance Energy Transfer (FRET). The masking of tPA-activity via steric hindrance created by albumin, and subsequent regeneration with therapeutic dose of heparin was tested by enzymatic assay. Stability of ‘camouflaged-tPA’ was determined in human plasma. Using fluorescence microscope, binding of camouflaged-tPA with activated platelets was monitored. Heparin modulated clot-lysis was evaluated in human blood clot. Results The anionic tPA retained ~ 97% activity of the unmodified-tPA. FRET experiments confirmed the electrostatic interaction between polyglutamate and protamine which was subsequently reversed by heparin. Complexation with HSA-protamine masked ~ 60% of tPA activity which was fully regenerated by heparin. The complex retained its prodrug character in human plasma after incubation at 37 °C. Fluorescence microscopic study confirmed binding of the construct with activated platelets. In lysing human clot, the camouflage could mask tPA-activity until it was triggered at a heparin level of 0.4 U/mL. Conclusion Oligoanion-modified tPA could be used for targeted/triggered delivery where its enzymatic activity could be masked by HSA-protamine conjugate and successfully regenerated by therapeutic dose of heparin.
To develop a novel method for rapid construction of Campylobacter jejuni deletion mutants. We used overlapping extension PCR protocol to amplify a target sequence region of Camp. jejuni genomic DNA ...in which an internal fragment, Cj0618 coding sequence, was replaced by a chloramphenicol resistance cassette. After the resulting PCR product was introduced into electrocompetent Camp. jejuni 81-176, chloramphenicol-resistant mutants in which the wild type allele has been replaced by the deletion cassette were selected. DNA sequencing confirmed precise deletion in the Cj0618 gene. As expected from the previously reported role of Cj0618 in chick colonization, the resulting deletion mutant showed a caecal colonization defect in chick infection. This method can be used for rapid construction of Camp. jejuni deletion mutants. The use of this method should facilitate functional characterization of various Camp. jejuni genes.
It remains controversial as to whether neonatal seizures have additional direct effects on the developing brain separate from the severity of the underlying encephalopathy. Using data collected from ...infants diagnosed with hypoxic-ischemic encephalopathy, and who were enrolled in an National Institute of Child Health and Human Development trial of hypothermia, we analyzed associations between neonatal clinical seizures and outcomes at 18 months of age. Of the 208 infants enrolled, 102 received whole body hypothermia and 106 were controls. Clinical seizures were generally noted during the first 4 days of life and rarely afterward. When adjustment was made for study treatment and severity of encephalopathy, seizures were not associated with death, or moderate or severe disability, or lower Bayley Mental Development Index scores at 18 months of life. Among infants diagnosed with hypoxic-ischemic encephalopathy, the mortality and morbidity often attributed to neonatal seizures can be better explained by the underlying severity of encephalopathy.
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