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Pokharel RK, Brisco L, Mandal M, Agrawal JP, Dillon D, Vitale M, Woodland P, Jacoby P, Downs J. Effect of sitting posture on development of scoliosis in Duchenne Muscular Dystrophy cases. JOURNAL OF NEPAL HEALTH RESEARCH COUNCIL 2014; 12:94-99. [PMID: 25575000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
BACKGROUND Scoliosis is a frequent association in boys with Duchenne Muscular Dystrophy when the ability to walk is lost around nine to 12 years of age. This study assessed the contribution of physical factors including lumbar posture to scoliosis in non-ambulatory youth with DMD in Nepal. METHODS Linear regression was used to assess effects of time since loss of ambulation, muscle strength, functional severity and lumbar angle as a binary variable on coronal Cobb angle; again logistic regression was used to assess effects of muscle strength and cross-legged sitting on the presence of a lordotic lumbar posture in 22 non-ambulant boys and young men. RESULTS The boys and young men had a mean (SD) age of 15.1 (4.0) years, had been non-ambulant for 48.6 (33.8) months and used a median of 3.5 (range 2 to 7) postures a day. The mean Cobb angle was 15.1 (range 0 to 70) degrees. Optimal accuracy in predicting scoliosis was obtained with a lumbar angle of -6° as measured by skin markers, and both a lumbar angle ≤-6° (P=0.112) and better functional ability (P=0.102) were associated with less scoliosis. Use of cross-legged sitting postures during the day was associated with a lumbar angle ≤-6° (OR 0.061; 95% CI 0.005 - 0.672; P=0.022). CONCLUSIONS Use of cross-legged sitting posture was associated with increase in lumbar lordosis. Higher angle of lumbar lordosis and better functional ability are associated with lesser degree of scoliosis.
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Downs J. Nutritional management of acute kidney injury in the critically ill: a focus on enteral feeding. SOUTH AFRICAN JOURNAL OF CLINICAL NUTRITION 2014. [DOI: 10.1080/16070658.2014.11734508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Lee JYL, Leonard H, Piek JP, Downs J. Early development and regression in Rett syndrome. Clin Genet 2013; 84:572-6. [DOI: 10.1111/cge.12110] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2012] [Revised: 01/21/2013] [Accepted: 01/21/2013] [Indexed: 11/30/2022]
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Davies GM, Bakker JD, Dettweiler-Robinson E, Dunwiddie PW, Hall SA, Downs J, Evans J. Trajectories of change in sagebrush steppe vegetation communities in relation to multiple wildfires. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2012; 22:1562-1577. [PMID: 22908714 DOI: 10.1890/10-2089.1] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Repeated perturbations, both biotic and abiotic, can lead to fundamental changes in the nature of ecosystems, including changes in state. Sagebrush steppe communities provide important habitat for wildlife and grazing for livestock. Fire is an integral part of these systems, but there is concern that increased ignition frequencies and invasive species are fundamentally altering them. Despite these issues, the majority of studies of fire effects in systems dominated by Artemisia tridentata wyomingensis have focused on the effects of single burns. The Arid Lands Ecology Reserve (ALE), in south-central Washington (U.S.A.), was one of the largest contiguous areas of sagebrush steppe habitat in the state until large wildfires burned the majority of it in 2000 and 2007. We analyzed data from permanent vegetation transects established in 1996 and resampled in 2002 and 2009. Our objective was to describe how the fires, and subsequent postfire restoration efforts, affected communities' successional pathways. Plant communities differed in response to repeated fire and restoration; these differences could largely be ascribed to the functional traits of the dominant species. Low-elevation communities, previously dominated by obligate seeders, moved furthest from their initial composition and were dominated by weedy, early-successional species in 2009. Higher-elevation sites with resprouting shrubs, native bunchgrasses, and few invasive species were generally more resilient to the effects of repeated disturbances. Shrub cover has been almost entirely removed from ALE, although there was some recovery where communities were dominated by resprouters. Bromus tectorum dominance was reduced by herbicide application in areas where it was previously abundant, but it increased significantly in untreated areas. Several resprouting species, notably Phlox longifolia and Poa secunda, expanded remarkably following competitive release from shrub canopies and/or abundant B. tectorum. Our results suggest that community dynamics can be understood through a state and transition model with two axes (shrub/grass and native/invasive abundance), although such models also need to account for differences in plant functional traits and disturbance regimes. We use our results to develop a conceptual model that will be validated with further research.
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Leonard H, Downs J, Jian L, Bebbington A, Jacoby P, Nagarajan L, Ravine D, Woodhead H. Valproate and risk of fracture in Rett syndrome. Arch Dis Child 2010; 95:444-8. [PMID: 20501539 DOI: 10.1136/adc.2008.148932] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES Some associations between antiepileptic drugs (AEDs) and fracture risk have been reported in the general population. This study investigated the relationships between fracture risk and commonly used AEDs in Rett syndrome, a genetic disorder associated with intellectual and physical disability. STUDY DESIGN Cases (n=233) were sourced from the population-based Australian Rett Syndrome Database and longitudinal data were used. The Cox proportional hazard model was used to analyse relationships between fracture and prescribed AEDs, mobility, epilepsy diagnosis and genotype. RESULTS After controlling for mobility, epilepsy diagnosis and genotype, use of valproate increased the risk of fracture threefold after at least 1 year (HR 3.56; 95% CI 1.85 to 6.82) and after 2 or more years (HR 3.02; 95% CI 1.90 to 4.80). There was a lesser increased risk (HR 1.99; 95% CI 0.99 to 4.02) with lamotrigine in the first year of use but not for subsequent years of use. Carbamazepine slightly decreased the risk (HR 0.60; 95% CI 0.35 to 1.02) after 2 or more years of use. CONCLUSIONS The effect of valproate on bone health should be considered when managing epilepsy in Rett syndrome. Multiple mechanisms could be contributing to this effect.
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Afoakwa E, Badham J, Blaauw R, Bourne L, Conradie N, Cooper P, Dannhauser A, Downs J, Faber M, Gericke G, Hanekom S, Hattingh Z, Hendricks M, Herselman M, Hussey G, Jerling J, Jooste P, Kinabo J, Kogi-Makau W, Kruger S, Kunneke E, Labuschagne I, MacIntyre U, Marais D, Marais M, Matji J, Maunder E, Muhammed Dhansay A, Naudé C, Norris S, Pettifor J, Saloojee H, Schaaf H, Schonfeldt H, Senekal M, Smalberger R, Smith A, Smuts M, Steenkamp L, Steyn N, Swart R, Van der Spuy D, Van Graan A, Van Jaarsveld P, Van Stuijvenberg M, Venter C, Venter I, Visser J, Vorster E, Walsh C, Wenhold F, Wentzel-Viljoen E, Wolmarans P. Editor’s Note. SOUTH AFRICAN JOURNAL OF CLINICAL NUTRITION 2008. [DOI: 10.1080/16070658.2008.11734170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Fyfe S, Downs J, McIlroy O, Burford B, Lister J, Reilly S, Laurvick CL, Philippe C, Msall M, Kaufmann WE, Ellaway C, Leonard H. Development of a Video-based Evaluation Tool in Rett Syndrome. J Autism Dev Disord 2006; 37:1636-46. [PMID: 17180458 DOI: 10.1007/s10803-006-0293-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2006] [Accepted: 09/20/2006] [Indexed: 11/30/2022]
Abstract
This paper describes the development of a video-based evaluation tool for use in Rett syndrome (RTT). Components include a parent-report checklist, and video filming and coding protocols that contain items on eating, drinking, communication, hand function and movements, personal care and mobility. Ninety-seven of the 169 families who initially agreed to participate returned a videotape within 8 months of the first request. Subjects whose videos were returned had a similar age profile to those who did not provide a video but were more likely to have classical than atypical RTT. Evidence of the content and social validity and inter-rater reliability on 11 videos is provided. Video may provide detailed, objective assessment of function and behaviour in RTT.
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Downs J, Gubbins K, Murad S, Gray C. Spherical harmonic expansion of the intermolecular site-site potential. Mol Phys 2006. [DOI: 10.1080/00268977900100111] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Fischhoff B, Parker AM, Downs J, Palmgren C, Dawes R, Manski CF. Teen expectations for significant life events. PUBLIC OPINION QUARTERLY 2000; 64:189-205. [PMID: 10984333 DOI: 10.1086/317762] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Downs J, Harrison RF, Cross SS. A decision support tool for the diagnosis of breast cancer based upon Fuzzy ARTMAP. Neural Comput Appl 1998. [DOI: 10.1007/bf01414167] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Downs J, Harrison RF, Kennedy RL, Cross SS. Application of the fuzzy ARTMAP neural network model to medical pattern classification tasks. Artif Intell Med 1996; 8:403-28. [PMID: 8870968 DOI: 10.1016/0933-3657(95)00044-5] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
This paper presents research into the application of the fuzzy ARTMAP neural network model to medical pattern classification tasks. A number of domains, both diagnostic and prognostic, are considered. Each such domain highlights a particularly useful aspect of the model. The first coronary care patient prognosis, demonstrates the ARTMAP voting strategy involving 'pooled' decision-making using a number of networks, each of which has learned a slightly different mapping of input features to pattern classes. The second domain, breast cancer diagnosis, demonstrates the model's symbolic rule extraction capabilities which support the validation and explanation of a network's predictions. The final domain, diagnosis of acute myocardial infarction, demonstrates a novel category pruning technique allowing the performance of a trained network to be altered so as to favour predictions of one class over another (e.g. trading sensitivity for specificity or vice versa). It also introduces a 'cascaded' variant of the voting strategy intended to allow identification of a subset of cases which the network has a very high certainty of classifying correctly.
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Hsu F, Liu A, Downs J, Rigamonti D, Humphrey J. A triplane video-based experimental system for studying axisymmetrically inflated biomembranes. IEEE Trans Biomed Eng 1995. [DOI: 10.1109/10.376148] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Zuo JM, Spence JCH, Downs J, Mayer J. Measurement of individual structure-factor phases with tenth-degree accuracy: the 00.2 reflection in BeO studied by electron and X-ray diffraction. Acta Crystallogr A 1993. [DOI: 10.1107/s0108767392010699] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023] Open
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Little CJ, Gettinby G, Downs J, Marshall CB. Consistency of results from the Vettest 8008 clinical biochemistry analyser. Vet Rec 1992; 130:419-24. [PMID: 1609476 DOI: 10.1136/vr.130.19.419] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Findings are presented on the precision of a clinical biochemistry analyser designed specifically for veterinary use. Twenty biochemical analytes have been examined in detail for variation within and between runs. The results indicate that the analyser can provide high precision for all the analytes with the possible exception of calcium, and suggest that the instrument can be used with confidence in the practice laboratory to aid diagnosis and to monitor biochemical changes in animals receiving treatment.
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Downs J, Ward J, Farmer R. Preoccupation with suicide in patients treated with fluoxetine. Am J Psychiatry 1991; 148:1090-1. [PMID: 1853968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Halperin HR, Tsitlik JE, Gelfand M, Downs J, Yin FC. Servo-controlled indenter for determining the transverse stiffness of ventricular muscle. IEEE Trans Biomed Eng 1991; 38:602-7. [PMID: 1879850 DOI: 10.1109/10.81586] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Regional ventricular wall stress is a critical determinant of cardiac function. There are, however, no validated methods for accurately estimating this stress. We have shown in the isolated ventricular septum that, during steady-state indentations, the transverse stiffness (the ratio of indentation stress [pressure acting on indenter face] to indentation strain [amount of indentation/nonindented thickness]) can be used as an estimate of the in-plane wall stress. Because of the long acquisition time for those transverse stiffness determinations, it was not possible to follow changes in wall stress over a single contraction. We recently developed a dynamic indentation system that can determine transverse stiffness in as little as 10 ms, allowing estimation of wall stress over a single contraction cycle. The apparatus consists of an indentation probe coupled to a linear motor. This indentation system was tested on two beating canine ventricular septa that were mounted in a biaxial system the could apply strains in the plane of the septa and measure the resulting in-plane stresses. The probe indented the septa with peak displacements of 0.1-0.5 mm at frequencies of 20 and 50 Hz. The transverse stiffness was calculated as the slope of the relation between the indentation stress and indentation strain during each high-frequency indentation. Consistent with earlier studies, the transverse stiffness was related to the inplane stress. In contrast to earlier studies, however, these dynamic transverse stiffness determinations could be made during a single contraction. Thus, dynamic transverse stiffness determinations allow estimation of wall stress in the isolated septa by minimal surface contact, and may lead to methods for estimating wall stress in the intact heart.
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Arkun Y, Downs J. A general method to calculate input-output gains and the relative gain array for integrating processes. Comput Chem Eng 1990. [DOI: 10.1016/0098-1354(90)85006-v] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Downs J, Halperin HR, Humphrey J, Yin F. An improved video-based computer tracking system for soft biomaterials testing. IEEE Trans Biomed Eng 1990; 37:903-7. [PMID: 2227976 DOI: 10.1109/10.58600] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We present an improved video-based computer system for on-line tracking of small markers moving in a plane. The system consists of a CCD camera, a video monitor, a dedicated 80386/20 microcomputer, a video frame grabber, and custom software. Up to four markers can be tracked at the 30-Hz video frame rate using a two-step, correlation-based search procedure. We discuss the requisite hardware and software requirements and illustrate how this tracking system can be used to collect strain data during biaxial stretching tests on planar soft tissues. Operating at 30 Hz, this system is an improvement over those previously reported, which are either slower or yield less information.
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Downs J, Dahmer SK, Battle AO. Multiple personality disorder in India. Am J Psychiatry 1990; 147:1260-1. [PMID: 2386273 DOI: 10.1176/ajp.147.9.aj14791260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Reddy SR, Talwalkar R, Downs J, Kotchen TA. Effect of linoleic acid infusion on blood pressure in normotensive and hypertensive rats. THE AMERICAN JOURNAL OF PHYSIOLOGY 1989; 257:H611-7. [PMID: 2764141 DOI: 10.1152/ajpheart.1989.257.2.h611] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
High dietary intake of linoleic acid lowers arterial pressure, and, in vitro, linoleic acid inhibits the enzymatic activity of renin. The purpose of the present study was 1) to evaluate the effect of intravenous infusion of linoleic acid on blood pressure in normotensive and hypertensive Sprague-Dawley rats and 2) to determine whether the hypotensive response to linoleic acid infusion is caused by inhibition of circulating renin. Blood pressure was decreased (P less than 0.01) by linoleic acid infusion in normotensive sodium chloride-deprived animals and in animals with two-kidney, one-clip hypertension. In contrast, linoleic acid infusion did not affect blood pressure in normotensive rats on a "normal" or high sodium chloride intake, in rats with deoxycorticosterone acetate (DOCA)-salt hypertension, and in anephric rats. In sodium chloride-deprived rats, the reduction of blood pressure by linoleic acid infusion was associated with increased plasma renin activity (P less than 0.05); serum angiotensin-converting enzyme activity was unchanged. The in vitro enzymatic activity of exogenous renin in plasma of anephric rats was not affected by linoleic acid infusion. In two-kidney, one-clip hypertensive animals, pretreatment with indomethacin did not alter the hypotensive response to linoleic acid. Thus, although linoleic acid infusion lowered blood pressure in high renin but not in low renin states, the reduction of blood pressure was not related to inhibition of circulating renin or to alterations of endogenous prostaglandin biosynthesis.
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Burch EA, Downs J. Development of neuroleptic malignant syndrome during simultaneous amoxapine treatment and alprazolam discontinuation. J Clin Psychopharmacol 1987; 7:55-6. [PMID: 3818996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Mirra JM, Gold R, Downs J, Eckardt JJ. A new histologic approach to the differentiation of enchondroma and chondrosarcoma of the bones. A clinicopathologic analysis of 51 cases. Clin Orthop Relat Res 1985:214-37. [PMID: 4064409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Fifty-one cases of central, hyalin cartilage tumors of the long and flat bones were analyzed. Although Grade 2 and 3 chondrosarcomas could be diagnosed on the basis of cytologic features alone, low-grade chondrosarcoma could not be adequately differentiated from pure, benign enchondroma(s) by cytology alone. The tumors can be distinguished by a new histologic approach based on tissue patterns. The crucial enchondroma patterns consist of multiple nodules of hyalin cartilage separated by normal marrow in conjunction with partial to complete encompassing plates of lamellar bone that conform to the irregular shapes of the cartilage nodules. The chondrosarcomatous patterns consist of a single confluent mass of cartilage, which commonly permeates the marrow, "trapping" host lamellar bone on all sides, and which forms bands of fibrosis between the confluent peripheral cartilage lobules. Other less common patterns included cartilagenous infiltration of the Haversian systems or marrow fat and/or the development of a soft tissue mass. A central secondary chondrosarcoma is defined as one that shows the combination of both the enchondromatous and chondrosarcomatous patterns. All 18 of the pure enchondromas diagnosed by the methods proposed in this article behaved with strict benignity (i.e., without evidence of recurrence or metastasis with an average follow-up period of 7.2 years). The 33 primary and secondary chondrosarcomas diagnosed using the described patterns behaved with the predicted frequency of recurrence, metastasis, and patient demise.
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Akiskal HS, Downs J, Jordan P, Watson S, Daugherty D, Pruitt DB. Affective disorders in referred children and younger siblings of manic-depressives. Mode of onset and prospective course. ARCHIVES OF GENERAL PSYCHIATRY 1985; 42:996-1003. [PMID: 4037989 DOI: 10.1001/archpsyc.1985.01790330076009] [Citation(s) in RCA: 262] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
We studied 68 referred juvenile offspring or siblings of adult bipolar patients. Mean age at onset of affective and related disturbances was 15.9 years (range, 6 to 24 years). Although four of the ten prepubertal children had hypomanic features, full-blown manic psychosis did not appear before puberty. In the sample at large, 12 were classified as dysthymic and ten as cyclothymic. Eleven additional subjects with polysubstance abuse, who at onset did not meet criteria for affective disorder, were reclassified as having either a dysthymic or a cyclothymic disorder during follow-up. Of the remaining patients--24 depressive, eight manic, and three mixed state--71% experienced recurrences; mood-incongruent features, present in four cases at onset, recurred in only one patient during subsequent episodes. Overall, half the sample evidenced signs of bipolarity during a mean prospective follow-up period of three years.
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Räsänen J, Heikkilä J, Downs J, Nikki P, Väisänen I, Viitanen A. Continuous positive airway pressure by face mask in acute cardiogenic pulmonary edema. Am J Cardiol 1985; 55:296-300. [PMID: 3881920 DOI: 10.1016/0002-9149(85)90364-9] [Citation(s) in RCA: 251] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The therapeutic efficacy of continuous positive airway pressure (CPAP) administered by face mask was studied in 40 patients with acute cardiogenic pulmonary edema and respiratory failure. Arterial blood gas values and pH, systemic arterial pressure, heart rate and respiratory rate were measured during administration of 30% oxygen with a high-flow face mask apparatus at ambient airway pressure. Twenty patients were then randomly chosen to continue ambient airway pressure breathing and 20 received 10 cm H2O of CPAP. The measurements were repeated 10, 60 and 180 minutes after therapy was initiated. During the first 10 minutes of CPAP treatment, arterial blood oxygen partial pressure increased 8 +/- 9 mm Hg (mean +/- 1 standard deviation), (p less than 0.01) and respiratory rate decreased 5 +/- 5 breaths/min (p less than 0.001). Systolic arterial pressure decreased 12 +/- 21 mm Hg (p less than 0.05), and heart rate by 10 +/- 11 beats/min (p less than 0.001). A decrease in respiratory rate by 2 +/- 5 breaths/min (p less than 0.05) was the only change that occurred in the control group. The improvement in arterial blood oxygenation persisted throughout the investigation period (p less than 0.05). Thirteen patients (65%) in the control group and 7 patients (35%) in the CPAP group met our criteria for treatment failure during the study (p = 0.068). Thus, CPAP administered by face mask improves gas exchange, decreases respiratory work, unloads circulatory stress, and may reduce the need for ventilator treatment in acute cardiogenic pulmonary edema.
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