1
|
Silvers SL, McDuffie CM, Yen DM, Rosenthal JN, Davis SE, Han JK. Two-year outcomes of radiofrequency device treatment of the nasal valve for nasal airway obstruction. Rhinology 2024:3153. [PMID: 38217847 DOI: 10.4193/rhinrhin23.377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2024]
Abstract
BACKGROUND Temperature-controlled radiofrequency (TCRF) device treatment of nasal valve dysfunction (NVD) was superior to a sham procedure control in reducing the symptoms of nasal airway obstruction (NAO) in this randomised controlled trial (RCT). METHODOLOGY Two-year outcomes for 108 patients actively treated in a prospective, multicenter, patient-blinded RCT were used to determine treatment effect durability and changes in medication/nasal dilator usage. A responder was defined as ≥20% reduction in NOSE score or ≥1 reduction in severity class. RESULTS The mean (SD) age of patients was 48.5 (12.3) years; 66 (61.1%) women. Baseline NOSE score was 76.3. The 2-year responder rate was 90.4% and NOSE score treatment effect was -41.7; 54.7% improvement. Of 57 patients using medications/nasal dilators at baseline, 45 (78.9%) either stopped all use (33.3%) or stopped/decreased (45.6%) use in ≥1 class at 2 years. Concurrent septal deviation, septal swell body, or turbinate enlargement did not significantly affect the odds of exhibiting a NOSE score of ≤25 at 2 years. CONCLUSIONS TCRF device treatment of NVD resulted in significant and sustained improvements in the symptoms of NAO at 2 years, accompanied by a substantial reduction in medication/nasal dilator use.
Collapse
Affiliation(s)
- S L Silvers
- Madison ENT and Facial Plastic Surgery, New York, NY, USA
| | | | - D M Yen
- Specialty Physician Associates, Bethlehem, PA, USA
| | - J N Rosenthal
- ENT and Allergy Associates of Florida, Coral Springs, FL, USA
| | - S E Davis
- Breath Clear Institute, Torrance, CA, USA
| | - J K Han
- Department of Otolaryngology - Head and Neck Surgery, Eastern Virginia Medical School, Norfolk, VI, USA
| |
Collapse
|
2
|
Cronin RM, Davis SE, Shenson JA, Chen Q, Rosenbloom ST, Jackson GP. Growth of Secure Messaging Through a Patient Portal as a Form of Outpatient Interaction across Clinical Specialties. Appl Clin Inform 2015; 6:288-304. [PMID: 26171076 DOI: 10.4338/aci-2014-12-ra-0117] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 03/03/2015] [Indexed: 01/12/2023] Open
Abstract
OBJECTIVE Patient portals are online applications that allow patients to interact with healthcare organizations. Portal adoption is increasing, and secure messaging between patients and healthcare providers is an emerging form of outpatient interaction. Research about portals and messaging has focused on medical specialties. We characterized adoption of secure messaging and the contribution of messaging to outpatient interactions across diverse clinical specialties after broad portal deployment. METHODS This retrospective cohort study at Vanderbilt University Medical Center examined use of patient-initiated secure messages and clinic visits in the three years following full deployment of a patient portal across adult and pediatric specialties. We measured the proportion of outpatient interactions (i.e., messages plus clinic visits) conducted through secure messaging by specialty over time. Generalized estimating equations measured the likelihood of message-based versus clinic outpatient interaction across clinical specialties. RESULTS Over the study period, 2,422,114 clinic visits occurred, and 82,159 unique portal users initiated 948,428 messages to 1,924 recipients. Medicine participated in the most message exchanges (742,454 messages; 78.3% of all messages sent), followed by surgery (84,001; 8.9%) and obstetrics/gynecology (53,424; 5.6%). The proportion of outpatient interaction through messaging increased from 12.9% in 2008 to 33.0% in 2009 and 39.8% in 2010 (p<0.001). Medicine had the highest proportion of outpatient interaction conducted through messaging in 2008 (23.3% of outpatient interactions in medicine). By 2010, this proportion was highest for obstetrics/gynecology (83.4%), dermatology (71.6%), and medicine (56.7%). Growth in likelihood of message-based interaction was greater for anesthesiology, dermatology, obstetrics/gynecology, pediatrics, and psychiatry than for medicine (p<0.001). CONCLUSIONS This study demonstrates rapid adoption of secure messaging across diverse clinical specialties, with messaging interactions exceeding face-to-face clinic visits for some specialties. As patient portal and secure messaging adoption increase beyond medicine and primary care, research is needed to understand the implications for provider workload and patient care.
Collapse
Affiliation(s)
- R M Cronin
- Vanderbilt University Medical Center Department of Biomedical Informatics , Nashville, Tennessee ; Vanderbilt University Medical Center Department of Medicine , Nashville, Tennessee ; Vanderbilt University Medical Center Department of Pediatrics , Nashville, Tennessee
| | - S E Davis
- Vanderbilt University Medical Center Department of Biomedical Informatics , Nashville, Tennessee
| | - J A Shenson
- Vanderbilt University Medical Center School of Medicine , Nashville, Tennessee
| | - Q Chen
- Vanderbilt University Medical Center Department of Biomedical Informatics , Nashville, Tennessee ; Vanderbilt University Medical Center Department of Biostatistics , Nashville, Tennessee
| | - S T Rosenbloom
- Vanderbilt University Medical Center Department of Biomedical Informatics , Nashville, Tennessee ; Vanderbilt University Medical Center Department of Medicine , Nashville, Tennessee ; Vanderbilt University Medical Center Department of Pediatrics , Nashville, Tennessee
| | - G P Jackson
- Vanderbilt University Medical Center Department of Biomedical Informatics , Nashville, Tennessee ; Vanderbilt University Medical Center Department of Pediatrics , Nashville, Tennessee ; Vanderbilt University Medical Center Department of Pediatric Surgery , Nashville, Tennessee
| |
Collapse
|
3
|
Denduluri N, Rugo HS, Davis SE, Favret A, Hong R, Au A, Moore DH, Esserman L. Concordance between the 21-gene recurrence score (RS) and the 70-gene profile (MP) in breast cancer (BC) patients (pts). J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.27_suppl.13] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
13 Background: Genomic assays are increasingly incorporated into treatment planning for pts with early stage BC to provide prognostic and/or predictive information. MP is a validated predictor of recurrence risk (RR) in pts without any treatment and RS is a validated predictor of RR in pts treated with 5 years of hormonal therapy (HT). Because concordance between RS and MP is largely unknown, we analyzed concordance in untreated pts that had both tests performed. Methods: Data are from 50 early stage BC pts treated at 4 US Oncology practices and the University of California, San Francisco. We used linear regression to test whether clinical features were related to discordance, measured as part of the gamma statistic. Results: Median age was 52.5 years, 16% (8 pts) had micro or macroscopic nodal involvement, and 66%, 30%, and 4% of pts had stage I, II, and III disease, respectively. All pts had estrogen receptor positive disease and 2 pts had HER2 overexpression by IHC or FISH. Concordance of MP and RS is shown below. Clinical features, including tumor size, grade, and HER2 were not significantly related to discordance. Gamma concordance was 0.64 (95% CI 0.28 to 0.98, p=0.0013). Conclusions: Concordance is high, mostly due to agreement in low risk scores. Five cases are truly discordant (MP low/RS intermediate or high) based on predicted outcomes. The 11 cases with high-risk MP with low risk RS may reflect endocrine sensitivity to 5 years of HT, or true discordance. Our identification of discordance should stimulate research to further clarify biology and elucidate the drivers of different types of risk. Large studies are underway to refine risk definition and treatment recommendations. [Table: see text]
Collapse
Affiliation(s)
- N. Denduluri
- US Oncology, Arlington, VA; University of California, San Francisco Helen Diller Family Comprehensive Cancer Center, San Francisco, CA; University of California, San Francisco, San Francisco, CA; US Oncology, Fairfax, VA; Virginia Hospital Center, Arlington, VA
| | - H. S. Rugo
- US Oncology, Arlington, VA; University of California, San Francisco Helen Diller Family Comprehensive Cancer Center, San Francisco, CA; University of California, San Francisco, San Francisco, CA; US Oncology, Fairfax, VA; Virginia Hospital Center, Arlington, VA
| | - S. E. Davis
- US Oncology, Arlington, VA; University of California, San Francisco Helen Diller Family Comprehensive Cancer Center, San Francisco, CA; University of California, San Francisco, San Francisco, CA; US Oncology, Fairfax, VA; Virginia Hospital Center, Arlington, VA
| | - A. Favret
- US Oncology, Arlington, VA; University of California, San Francisco Helen Diller Family Comprehensive Cancer Center, San Francisco, CA; University of California, San Francisco, San Francisco, CA; US Oncology, Fairfax, VA; Virginia Hospital Center, Arlington, VA
| | - R. Hong
- US Oncology, Arlington, VA; University of California, San Francisco Helen Diller Family Comprehensive Cancer Center, San Francisco, CA; University of California, San Francisco, San Francisco, CA; US Oncology, Fairfax, VA; Virginia Hospital Center, Arlington, VA
| | - A. Au
- US Oncology, Arlington, VA; University of California, San Francisco Helen Diller Family Comprehensive Cancer Center, San Francisco, CA; University of California, San Francisco, San Francisco, CA; US Oncology, Fairfax, VA; Virginia Hospital Center, Arlington, VA
| | - D. H. Moore
- US Oncology, Arlington, VA; University of California, San Francisco Helen Diller Family Comprehensive Cancer Center, San Francisco, CA; University of California, San Francisco, San Francisco, CA; US Oncology, Fairfax, VA; Virginia Hospital Center, Arlington, VA
| | - L. Esserman
- US Oncology, Arlington, VA; University of California, San Francisco Helen Diller Family Comprehensive Cancer Center, San Francisco, CA; University of California, San Francisco, San Francisco, CA; US Oncology, Fairfax, VA; Virginia Hospital Center, Arlington, VA
| |
Collapse
|
4
|
Magbanua MM, Davis SE, Crothers J, Sosa E, Haqq CM, van't Veer L, Esserman L. Gene expression in serial biopsies in locally advanced breast cancer patients who failed to respond to neoadjuvant chemotherapy. J Clin Oncol 2010. [DOI: 10.1200/jco.2010.28.15_suppl.10515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
|
5
|
van 't Veer LJ, Esserman LJ, Linn S, Rutgers E, Knauer M, Retel V, Davis SE, Lin C. Evaluation of the effect of screening on the detection of good and poor prognosis breast cancers. J Clin Oncol 2009. [DOI: 10.1200/jco.2009.27.15_suppl.1525] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
1525 Background: Since the advent of screening, breast cancer incidence has significantly increased in the United States as well as other countries. SEER data from the US shows that the increase is largely in localized disease without a concomitant or significant decrease in regionalized disease. In addition, the increase has occurred essentially in women over 50. We asked whether molecular characterization of tumors would shed light on the types of tumors detected in screening and in locally advanced breast cancers (LABC). Methods: We identified two groups of patients from European studies before and after the introduction of population based screened (in 1995) where the 70-gene prognosis test (MammaPrint) results were available. The first source is the European Validation Study (EVS) (Buyse et al, J Natl Cancer Inst. 2006). The second was a prospective implementation trial of MammaPrint in the Netherlands (RASTER study) (Bueno de Mesquita et al, Lancet Oncol. 2007). The source of LABC patients comes from the multicenter I-SPY TRIAL (CALGB 150007/150012) who underwent routine screening (prior mammogram within 2 years of diagnosis). Results: In women age 50–60, the fraction of cancers that were MammaPrint good prognosis were 40% and 60% prior to and after the introduction of screening, respectively. For women 50–60 who were actually undergoing screening, the fraction of tumors that were MammaPrint good prognosis was 67%. For patients aged 30–40 with stage I and II lymph node-negative disease, who did not undergo screening in either period, the fraction of MammaPrint good prognosis tumors did not change (29% and 31%, for EVS and Raster, respectively). For patients with LABC, from the I-SPY TRIAL, the fraction of tumors that are MammaPrint good prognosis is 7% and 29% for women aged 30–40 and 50–60, respectively. Of the LABC patients undergoing screening, 80% presented clinically during the interval between routine mammograms. Conclusions: Current screening programs are increasing the burden of low-risk cancers. Screening programs should consider including molecular profiles at the time of diagnosis to reduce overtreatment. The majority of LABCs have high-risk molecular profiles and do not present as screen detected cancers. New strategies are needed for early detection of LABC. [Table: see text]
Collapse
Affiliation(s)
- L. J. van 't Veer
- UCSF, San Francisco, CA; Netherlands Cancer Institute, Amsterdam, Netherlands; I-SPY Network, San Francisco, CA
| | - L. J. Esserman
- UCSF, San Francisco, CA; Netherlands Cancer Institute, Amsterdam, Netherlands; I-SPY Network, San Francisco, CA
| | - S. Linn
- UCSF, San Francisco, CA; Netherlands Cancer Institute, Amsterdam, Netherlands; I-SPY Network, San Francisco, CA
| | - E. Rutgers
- UCSF, San Francisco, CA; Netherlands Cancer Institute, Amsterdam, Netherlands; I-SPY Network, San Francisco, CA
| | - M. Knauer
- UCSF, San Francisco, CA; Netherlands Cancer Institute, Amsterdam, Netherlands; I-SPY Network, San Francisco, CA
| | - V. Retel
- UCSF, San Francisco, CA; Netherlands Cancer Institute, Amsterdam, Netherlands; I-SPY Network, San Francisco, CA
| | - S. E. Davis
- UCSF, San Francisco, CA; Netherlands Cancer Institute, Amsterdam, Netherlands; I-SPY Network, San Francisco, CA
| | - C. Lin
- UCSF, San Francisco, CA; Netherlands Cancer Institute, Amsterdam, Netherlands; I-SPY Network, San Francisco, CA
| |
Collapse
|
6
|
Esserman LJ, van't Veer LJ, Perou C, Rutgers EJ, Davis SE. Biology of breast cancers that present as interval cancers and at young age should inform how we approach early detection and prevention. Cancer Res 2009. [DOI: 10.1158/0008-5472.sabcs-6034] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Abstract #6034
Population screening has increased the absolute number of breast cancer cases. In spite of widespread screening, there are still many patients who present with locally advanced breast cancer, often women who are young or who present with a mass between annual screens (“interval cancers”). Molecular profiling provides the opportunity to determine whether mammographically detected cancers are biologically distinct from locally advanced breast cancers. Methods: Tumor samples from the time of diagnosis (2002-2006), from patients with locally advanced breast cancers enrolled on the multi-site I-SPY TRIAL (CALGB 150007/150012 and ACRIN 6657) were compared to stage 1 & 2 tumor samples collected in 2004 from multiple community Netherlands hospitals (RASTER dataset). The NKI 70 gene set was performed on 100 of 221 patients (80 more samples pending) from I-SPY and 228 of 242 patients from the RASTER dataset. The proportion of good vs. poor prognosis profiles were compared. Additionally, we have collected data on response to chemotherapy from the I-SPY patients. Finally, mammograms from the I-SPY and RASTER datasets are being reviewed to enable classification of tumors by presentation (palpable, screen detected, and interval cancer and negative prior mammogram within 1 year). Results: I-SPY data includes 221 patients with tumors ≥3cm in size; median tumor size is 6cm; 55% were <50 years old; 44% were ER negative. Only 20% had an NKI 70 gene good prognosis at time of diagnosis. The percentage of women under <40, 41-50, and >50, with a good prognosis is 10%, 23%, and 22%, respectively. The RASTER dataset included 427 patients from age 30 to 61. NKI 70 gene profiles are available in 219 patients: 66% were Stage 1; 33% were Stage 2. Overall, 51% had a NKI 70 gene good prognosis profile. For women under the age of 40, 31% had a NKI 70 gene poor prognosis. For women 40-50, and >50, the fraction of NKI 70 gene poor prognosis is 55% and 56%, respectively. Data will be presented based on mode of detection: screen vs. palpation (never screened vs. interval). Conclusion: The key observation is that the fraction of good prognosis tumors substantially increases with age. In patients too young for screening, the fraction of poor prognosis tumors is 69%. Patients who present with locally advanced breast cancers who are too young to be screened almost always have a poor prognosis signature. This may extend to those with interval cancers. This suggests that the tumors identified by screening, although they are early stage cancers, are not the precursors of the poor prognosis tumors in young women and those with locally advanced disease. Therefore, we may not be able to rely on current screening approaches to improve outcomes for young women and those with interval cancers. Further analysis will include reviewing interval cancer cases within the I-SPY dataset and assessing prognostic indicators.
Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6034.
Collapse
Affiliation(s)
| | - LJ van't Veer
- 2 Netherlands Cancer Institute, Amsterdam, Netherlands
| | - C Perou
- 3 UNC-Chapel Hill, Chapel Hill, NC
| | - EJ Rutgers
- 2 Netherlands Cancer Institute, Amsterdam, Netherlands
| | | | | |
Collapse
|
7
|
Krause KL, Forster HV, Kiner T, Davis SE, Bonis JM, Qian B, Pan LG. Normal breathing pattern and arterial blood gases in awake and sleeping goats after near total destruction of the presumed pre-Botzinger complex and the surrounding region. J Appl Physiol (1985) 2008; 106:605-19. [PMID: 19095752 DOI: 10.1152/japplphysiol.90966.2008] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Abrupt neurotoxic destruction of >70% of the pre-Bötzinger complex (preBötzC) in awake goats results in respiratory and cardiac failure (Wenninger JM, Pan LG, Klum L, Leekley T, Bastastic J, Hodges MR, Feroah TR, Davis S, Forster HV. J Appl Physiol 97: 1629-1636, 2004). However, in reduced preparations, rhythmic respiratory activity has been found in other areas of the brain stem (Huang Q, St. John WM. J Appl Physiol 64: 1405-1411, 1988; Janczewski WA, Feldman JL. J Physiol 570: 407-420, 2006; Lieske SP, Thoby-Brisson M, Telgkamo P, Ramierz JM. Nature Neurosci 3: 600-607, 2000; St. John WM, Bledsoe TA. J Appl Physiol 59: 684-690, 1985); thus we hypothesized that, when the preBötzC is destroyed incrementally over weeks, time-dependent plasticity within the respiratory network will result in a respiratory rhythm capable of maintaining normal blood gases. Microtubules were bilaterally implanted into the presumed preBötzC of seven goats. After recovery from surgery, studies were completed to establish baseline values for respiratory parameters. At weekly intervals, increasing volumes (in order 0.5, 1, 5, and 10 microl) of ibotenic acid (IA; 50 mM) were then injected into the preBötzC. All IA injections resulted in an acute tachypnea and dysrhythmia featuring augmented breaths, apneas, and increased breath-to-breath variation in breathing. In studies at night, apneas were nearly all central and occurred in the awake state. Breath-to-breath variation in breathing was greater (P < 0.05) during wakefulness than during non-rapid eye movement sleep. However, one week after the final IA injection, the breathing pattern, breath-to-breath variation, and arterial blood gases and pH were unchanged from baseline, but there was a 20% decrease in respiratory frequency (f) and CO(2) sensitivity (P < 0.05), as well as a 40% decrease in the ventilatory response to hypoxia (P < 0.001). In subsequent histological analysis of the presumed preBötzC region of lesioned goats, it was determined that there was a 90 and 92% reduction from control goats in total and neurokinin-1 receptor neurons, respectively. Therefore, it was concluded that 1) the dysrhythmic effects on breathing are state dependent; and 2) after incremental, near total destruction of the presumed preBötzC region, time-dependent plasticity within the respiratory network provides a rhythm capable of sustaining normal arterial blood gases.
Collapse
Affiliation(s)
- K L Krause
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, USA.
| | | | | | | | | | | | | |
Collapse
|
8
|
Krause KL, Forster HV, Davis SE, Kiner T, Bonis JM, Pan LG, Qian B. Focal acidosis in the pre-Botzinger complex area of awake goats induces a mild tachypnea. J Appl Physiol (1985) 2008; 106:241-50. [PMID: 19008492 DOI: 10.1152/japplphysiol.90547.2008] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
There are widespread chemosensitive areas in the brain with varying effects on breathing. In the awake goat, microdialyzing (MD) 50% CO(2) at multiple sites within the medullary raphe increases pulmonary ventilation (Vi), blood pressure, heart rate, and metabolic rate (Vo(2)) (11), while MD in the rostral and caudal cerebellar fastigial nucleus has a stimulating and depressant effect, respectively, on these variables (17). In the anesthetized cat, the pre-Bötzinger complex (preBötzC), a hypothesized respiratory rhythm generator, increases phrenic nerve activity after an acetazolamide-induced acidosis (31, 32). To gain insight into the effects of focal acidosis (FA) within the preBötzC during physiological conditions, we tested the hypothesis that FA in the preBötzC during wakefulness would stimulate breathing, by increasing respiratory frequency (f). Microtubules were bilaterally implanted into the preBötzC of 10 goats. Unilateral MD of mock cerebral spinal fluid equilibrated with 6.4% CO(2) did not affect Vi, tidal volume (Vt), or f. Unilateral MD of 25 and 50% CO(2) significantly increased Vi and f by 10% (P < 0.05, n = 10, 17 trials), but Vt was unaffected. Bilateral MD of 6.4, 25, or 50% CO(2) did not significantly affect Vi, Vt, or f (P > 0.05, n = 6, 6 trials). MD of 80% CO(2) caused a 180% increase in f and severe disruptions in airflow (n = 2). MD of any level of CO(2) did not result in any significant changes in mean arterial blood pressure, heart rate, or Vo(2). Thus the data suggest that the preBötzC area is chemosensitive, but the responses to FA at this site are unique compared with other chemosensitive sites.
Collapse
Affiliation(s)
- K L Krause
- Department of Physiology, Medical College of Wisconsin, Milwaukee,WI, USA.
| | | | | | | | | | | | | |
Collapse
|
9
|
|
10
|
Abstract
Ventilatory sensitivity to CO2 in awake adult Brown Norway (BN) rats is 50–75% lower than in adult Sprague-Dawley (SD) and salt-sensitive Dahl S (SS) rats. The purpose of the present study was to test the hypothesis that this difference would be apparent during the development of CO2 sensitivity. Four litters of each strain were divided into four groups such that rats were exposed to 7% inspired CO2 for 5 min in a plethysmograph every third day from postnatal day (P) 0 to P21 and again on P29 and P30. From P0 to P14, CO2 exposure increased pulmonary ventilation (V̇e) by 25–50% in the BN and SD strains and between 25 to over 200% in the SS strain. In all strains beginning around P15, the response to CO2 increased progressively reaching a peak at P19–21 when V̇e during hypercapnia was 175–225% above eucapnia. There were minimal changes in CO2 sensitivity between P21 and P30, and at both ages there were minimal between-strain differences. At P30, the response to CO2 in the SS and SD strains was near the adult response, but the response in the BN rats was 100% greater at P30 than in adults. We conclude that 1) CO2-sensing mechanisms, and/or mechanisms downstream from the chemoreceptors, change dramatically at the age in rats when other physiological systems are also maturing (∼P15), and 2) there is a high degree of age-dependent plasticity in CO2 sensitivity in rats, which differs between strains.
Collapse
Affiliation(s)
- S E Davis
- Department of Physiology, Medical College of Wisconsin and Zablocki Veterans Affairs Medical Center, Milwaukee, USA
| | | | | | | | | | | |
Collapse
|
11
|
|
12
|
Abstract
We report a case of a 19-year-old female with complete androgen insensitivity syndrome (CAIS) who was diagnosed with a juvenile fibdroadenoma of the breast. The patient presented at age 18 with primary amenorrhea. She had been raised as a female and went through thelarche at age 13 and adrenarche at age 14. She had two sisters and three maternal aunts with androgen insensitivity syndrome. Physical exam revealed that the patient had no cervix, and a pelvic sonogram confirmed that the uterus was absent. Genetic analysis revealed a 46 XY karyotype. Bilateral intra-abdominal testes were noted on ultrasound and subsequently removed. She was placed on synthetic estrogen replacement therapy. Roughly 1 year following orchiectomy, the patient noticed an enlarging mass in her right breast. Physical exam revealed a roughly 5 cm mobile mass in the upper portion of the nipple-areolar complex. Ultrasound showed a solid mass consistent with a fibroadenoma. Because of the size of the lesion and the patient's hormonal make-up, a fine needle aspirate was obtained. Cytopathology showed large cohesive sheets of ductal epithelial cells, scattered histiocytes, numerous bare nuclei, fragments of fibrous tissue and metachromatic stroma. Some of the stroma was noted to be cellular. The tumor was subsequently excised. Microscopically, the lesion had epithelial and stromal hyperplasia consistent with a fibroadenoma. Phyllodes-like qualities of large size, increased stromal cellularity, and intracanalicular growth ("leaf-like projections") were noted; however, the pathologist found that the florid epithelial hyperplasia and the patient's young age were more compatible with a juvenile fibroadenoma. We describe what we believe to be the first report of a patient with CAIS and a fibroadenoma of the breast. The hormonal imbalance typically found in these patients, combined with the fact that most individuals with CAIS receive exogenous estrogen therapy, suggests that there may be a relatively high incidence of fibroadenoma in these patients.
Collapse
Affiliation(s)
- S E Davis
- Department of Surgery and Breast Care Unit, University of California, San Diego, School of Medicine, La Jolla, California, USA.
| | | |
Collapse
|
13
|
Davis SE, Levy ML, McComb JG, Sposto R. The delta valve: how does its clinical performance compare with two other pressure differential valves without antisiphon control? Pediatr Neurosurg 2000; 33:58-63. [PMID: 11070430 DOI: 10.1159/000028988] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
OBJECTIVE The Delta valve is a pressure differential valve with a siphon control device. The valve mechanism is normally closed, but is designed to open in response to positive ventricular pressure, thereby avoiding overdrainage of cerebrospinal fluid (CSF). As a result, the incidence of subdural fluid collections as well as postural symptoms is purportedly reduced. In addition, the valve might reduce the number of obstructions as there would be no negative pressure sucking tissue and debris into the shunt system. In order to assess whether use of the Delta valve reduced the number of shunt-related problems as compared with two other pressure differential valves without an antisiphon component, we performed a retrospective review of all children undergoing CSF diversion procedures at our institution. METHODS We reviewed the charts of 1, 193 patients. Cases included 2,325 ventriculoperitoneal (V-P) shunt insertions or revisions from January 1, 1985, to December 31, 1994, performed at our institution. The Delta valve and two pressure differential valves without antisiphon function were exclusively inserted during the following time periods: Holter-Hausner (H-H): January 1, 1985, to August, 1987; Heyer-Schulte (H-S): August, 1987, to June, 1991, and Delta: June, 1991, to December 31, 1994. RESULTS Of the cases reviewed, 475 patients underwent insertion of a V-P shunt at the Childrens Hospital of Los Angeles and had a total of 686 shunt operations. Median follow-up was 3 years and ranged up to 10 years. Kaplan-Meier analysis documented that 67% of H-H, 71% of H-S and 70% of the Delta valves were functioning at 1-year follow-up. At 2-year follow-up, 66% of H-H, 64% of H-S and 65% of the Delta valves were functioning. The difference was not statistically significant. The occurrence rate for symptomatic subdural fluid collections was 0.7% (1/130) for H-H, 2.2% (3/139) for H-S and 1.0% (2/206) for the Delta valve (p = 0.52). The combined breakage/obstruction rate for the series was 7.7% (10/130) for H-H, 2.9% (4/139) for H-S and 4.9% (10/206) for the Delta valve (p = 0.19). No Delta valves malfunctioned secondary to fibrous capsule affecting the antisiphon device. CONCLUSIONS In conclusion, it appears that performance of the Delta valve was not significantly different from the H-H and H-S valves, two valves without an antisiphon device. There was no significant difference in the occurrence of symptomatic subdural fluid collections based upon valve type, or in the combined valve breakage/obstruction rates based upon valve type.
Collapse
Affiliation(s)
- S E Davis
- Division of Neurosurgery, Childrens Hospital Los Angeles, and the Department of Neurologic Surgery, Los Angeles, Calif., USA
| | | | | | | |
Collapse
|
14
|
Abstract
Hand function was provided for a six-year-old child with C-5 American Spinal Injuries Association (ASIA) classification-A tetraplegia through a percutaneous intramuscular (i.m.) functional electrical stimulation (FES) system. In conjunction with implantation of 10 percutaneous i.m. electrodes for provision of grasp and release of her right hand, reconstructive surgery was performed to provide upper extremity positioning to optimize hand use. The subject participated in FES training over a nine-week period for approximately five hours weekly, with an additional five hours each week dedicated to exercise and conditioning of her arm muscles. Physical and functional assessments included range of motion (ROM), manual muscle testing (MMT), activities of daily living (ADL) abilities and the Canadian Occupational Performance Measure (COPM), used to evaluate the effect of stimulated hand function and surgical reconstruction on functional ability. These were conducted prior to FES and surgery and repeated after rehabilitation training. With rehabilitation and training, the child was able to control her FES system. Physical assessments revealed increased strength of both shoulders and more useful range of arm movement. Functional assessments show that the FES system enabled her to perform age-appropriate ADL that previously were achievable only with physical assistance. Her overall level of independence in ADL ability increased, as did self-rated levels of satisfaction and performance on chosen activities. Positive gains demonstrated here suggest the need for further studies of FES systems in young children with SCI.
Collapse
Affiliation(s)
- S E Davis
- Shriners Hospitals for Children, Philadelphia, PA 19140, USA
| | | | | | | |
Collapse
|
15
|
Abstract
The extent of the change in thermal diffusivity of soft tissues due to heat-induced damage is not well known. Reported here are the results of using the flash method to measure the through-the-wall component of thermal diffusivity of bovine aorta before and after the tissue has undergone two hours of heating at 75 degrees C. The measurements indicate a 10.1 percent increase in the thermal diffusivity of the tissue post-heating. While this change may not result in a significant change in the tissue temperature profile, further study is needed to quantify the thermal diffusivity in other coordinate directions, as well as the mechanisms by which this change in properties occurs.
Collapse
Affiliation(s)
- S E Davis
- Department of Mechanical Engineering, University of Maryland, Baltimore 21250, USA
| | | | | | | |
Collapse
|
16
|
Abstract
Two groups of children and a control group of adults completed a visual memory task previously shown to produce representational momentum in adults. In the task, a computer-animated target was shown moving either horizontally or vertically, and the target vanished without warning. After the target vanished, observers indicated the location at which it had vanished. Both children and adults exhibited representational momentum, i.e., indicated locations slightly beyond where the target actually disappeared, and the magnitude of representational momentum was larger for younger children than adults. Implications of the results for issues of sensitivity to dynamics and for reliance on analogue representation are discussed.
Collapse
Affiliation(s)
- T L Hubbard
- Department of Psychology, Texas Christian University, Fort Worth 76129, USA.
| | | | | |
Collapse
|
17
|
Abstract
Some studies indicate that infants, especially those less than 1 month of age have a higher incidence of ventriculoperitoneal shunt infections. To look at age as well as other variables that might relate to the rate of shunt infection, we reviewed the records of all patients undergoing a ventriculoperitoneal shunt insertion or revision at our institution from January 1, 1985, to December 31, 1994. There were a total of 2,325 ventriculoperitoneal shunting procedures performed on 1,193 patients with a male:female ratio of 678:515. The overall infection rate was 3.2% (74 infections). Analyzed by age, the infection rates were as follows: <1 month 9/223 (4.0%), 1-6 months 16/449 (3.6%), 6-12 months 13/297 (4.4%), 12-18 months 3/122 (2.5%), 18-24 months 7/116 (6.0%) and 24+ months 26/1, 118 (2.3%). There was no statistically significant difference between age groups (p > 0.05). Upon selectively examining premature neonates who developed hydrocephalus secondary to intraventricular hemorrhage from the figures given above, one finds that 2/44 (4.5%) of neonates became infected, which was also not significant. The infection rate was the same irrespective of whether the procedure was to insert or revise the shunt, or whether another operative procedure was done under the same anesthesia. The etiology of the hydrocephalus was not a factor, nor was the presence of an open neural tube defect. The presence of fluid accumulation along the shunt tract or at another neurological operative site was associated with a significant increase in incidence of infection 15/168 (8.9%) when compared to those with no fluid accumulation (p < 0.001). The type of infecting organism was divided roughly in thirds, with relatively equal representation from Staphylococcus epidermidis/coagulase negative and Staphylococcus aureus. The remaining third was comprised of a wide variety of organisms.
Collapse
Affiliation(s)
- S E Davis
- Division of Neurosurgery, Childrens Hospital of Los Angeles and the Department of Neurological Surgery, University of Southern California School of Medicine, Los Angeles, Calif., USA
| | | | | | | |
Collapse
|
18
|
Abstract
The Freehand System, an eight-channel functional electrical stimulation (FES) system, was implanted in five adolescents with C-5 or C-6 tetraplegia to provide stimulated lateral pinch and palmar grasp. Following completion of inpatient training on how to use the Freehand System for predefined and self-selected activities of daily living (ADL), the adolescents were discharged to use their Freehand systems at home and school. A telephone survey was administered on a weekly basis to obtain information on the type of ADL performed with the Freehand System, reasons for not using the Freehand System, and perceived barriers and motivators to FES use. Twenty surveys were obtained on each adolescent, resulting in a total of 100 surveys. The most common type of activity performed with the Freehand System was self-care, which included tasks such as eating, grooming, and brushing teeth. The Freehand System was also used for productivity activities defined as writing, socialization, and manipulation of school and household objects. Motivators to Freehand System use included perceived need and importance to perform an ADL in an independent fashion, physical ease of using the Freehand System, and availability of social supports that facilitated Freehand System use. While there were several reported barriers to Freehand System use, incompatibility with multiple transfers to and from the wheelchair and lack of physical assistance during morning care to don the system were perceived as two of the more common reasons for nonuse.
Collapse
Affiliation(s)
- S E Davis
- Shriners Hospitals for Children, Philadelphia, PA 19140, USA
| | | | | | | |
Collapse
|
19
|
Womack CJ, Davis SE, Weltman JY, Blumer J, Barrett EJ, Gaesser GA, Weltman A. The effect of training and epinephrine infusion on ratings of perceived exertion (RPE). Int J Sports Med 1998; 19:121-4. [PMID: 9562221 DOI: 10.1055/s-2007-971893] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Seven untrained males (mean age [+/-SD] = 25.6+/-3.9 yr, mean ht = 177.0+/-5.9 cm, mean wt = 65.8+/-7.4 kg) completed a 6-week exercise program (cycle ergometer). Prior to training, and at the end of each week of training, each subject performed a 20 min constant-power exercise test (absolute power was the same each week). At the end of the six week training program (within a few days), an additional 20 min constant-power test was performed, during which epinephrine was infused at a rate of 100 ng x kg(-1) x min(-1) over the final 10 min of exercise. Training significantly (P<0.05) reduced end-exercise ratings of perceived exertion (RPE), plasma epinephrine concentration [Epi], plasma norepinephrine concentration [NE], blood lactate concentration [La-], minute ventilation (V(E)), heart rate (HR), and blood glucose concentration [Glc]. Epinephrine infusion failed to increase RPE despite significant (p < 0.05) increases in [Epi], [La-], V(E) and [Glc]. Therefore, the present data indicate that RPE during exercise is not causally related to changes in plasma [Epi]. It also appears that modest changes in plasma [NE], blood [La-], V(E) and blood [Glc] during constant-power cycle ergometry (as observed during Epi infusion) do not impact RPE.
Collapse
Affiliation(s)
- C J Womack
- Exercise Physiology Laboratory, General Clinical Research Center, Charlottesville, VA 22903, USA
| | | | | | | | | | | | | |
Collapse
|
20
|
Mulcahey MJ, Betz RR, Smith BT, Weiss AA, Davis SE. Implanted functional electrical stimulation hand system in adolescents with spinal injuries: an evaluation. Arch Phys Med Rehabil 1997; 78:597-607. [PMID: 9196467 DOI: 10.1016/s0003-9993(97)90425-1] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE To study the utility and functional benefits of an implanted functional electrical stimulation (FES) system for hand grasp and release in adolescents with tetraplegia secondary to spinal cord injuries. DESIGN Intervention study with before-after trial measurement with each subject as his or her own control. SETTING Nonprofit pediatric orthopedic rehabilitation facility specializing in spinal cord injury. PARTICIPANTS A convenience sample of five adolescents between 16 and 18 years of age with C5 or C6 level tetraplegia at least 1 year after traumatic spinal cord injury. Key muscles for palmar and lateral grasp and release were excitable by electrical stimulation. INTERVENTIONS A multichannel stimulator/receiver and eight electrodes were surgically implanted to provide stimulated palmar and lateral grasp and release. In conjunction with implantation of the FES hand system, surgical reconstruction in the form of tendon transfers, tendon lengthenings and releases, and joint arthrodeses was performed to augment stimulated hand function. Rehabilitation of the tendon transfers and training in the use of the FES hand system were provided. MAIN OUTCOME MEASURES Measurements of pinch and grasp force, the Grasp and Release Test (GRT), and an assessment of six activities of daily living (ADL) were administered before implantation of the FES hand system and at regular follow-up intervals. Results of the stimulated response of individual muscles and surgical reconstruction were evaluated using standard and stimulated muscle testing techniques and standard assessment of joint range of motion. All subjects completed followup testing. RESULTS Lateral and palmar forces were significantly greater than baseline forces (p = .043). Heavy objects on the GRT could only be manipulated with FES, and FES increased the level of independence in 25 of 30 ADL comparisons (5 subjects, 6 activities) as compared to baseline. After training, FES was preferred in 21 of 30 comparisons over the typical means of task completion. Of the 40 electrodes implanted, 37 continue to provide excellent stimulated responses and all of the implanted stimulators have functioned without problems. The surgical reconstruction procedures greatly enhanced FES hand function by either expanding the workspace in which to utilize FES (deltoid to triceps transfer), stabilizing the wrist (brachioradialis to wrist extensor transfer), or stabilizing joints (intrinsic tenodesis transfer, FPL split transfer). CONCLUSION For five adolescents with tetraplegia, the combination of FES and surgical reconstruction provided active palmar and lateral grasp and release. Laboratory-based assessments demonstrated that the FES system increased pinch force, improved the manipulation of objects, and typically increased independence in six standard ADL as compared to pre-FES hand function. The study also showed that the five adolescents generally preferred FES for most of the ADL tested. Data on the benefits of the implanted FES hand system outside of the laboratory are needed to understand the full potential of FES.
Collapse
Affiliation(s)
- M J Mulcahey
- Research Department, Shriners Hospital for Children, Philadelphia, PA 19152, USA
| | | | | | | | | |
Collapse
|
21
|
Weltman A, Weltman JY, Womack CJ, Davis SE, Blumer JL, Gaesser GA, Hartman ML. Exercise training decreases the growth hormone (GH) response to acute constant-load exercise. Med Sci Sports Exerc 1997; 29:669-76. [PMID: 9140905 DOI: 10.1097/00005768-199705000-00013] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
To assess the influence of exercise training on the growth hormone (GH) response to acute exercise, six untrained males completed a 20-min, high-intensity, constant-load exercise test prior to and after 3 and 6 wk of training (the absolute power output (PO) during each test remained constant x PO = 182.5 +/- 29.5 W). Training increased (pre- vs post-training) oxygen uptake (VO2) at lactate threshold (1.57 +/- 0.33 L.min-1 vs 1.97 +/- 0.24 L.min-1 P < or = 0.05). VO2 at 2.5 mM blood lactate concentration ([HLa]) (1.83 +/- 0.38 L.min-1 vs 2.33 +/- 0.38 L.min-1, P < or = 0.05), and VO2peak (3.15 +/- 0.54 L.min-1 vs 3.41 +/- 0.47 L.min-1, P < or = 0.05). Power output at the lactate threshold (PO-LT) increased with training from 103 +/- 28 to 132 +/- 23W (P < or = 0.05). Integrated GH concentration (20 min exercise + 45 min recovery) (microgram.L-1 x min) after 3 wk (138 +/- 106) and 6 wk (130 +/- 145) were significantly lower (P < or = 0.05) than pre-training (238 +/- 145). Plasma epinephrine and norepinephrine responses to training were similar to the GH response (EPI-pre-training = 2447 +/- 1110; week 3 = 1046 +/- 144; week 6 = 955 +/- 322 pmol.L-1; P < or = 0.05; NE pre-training = 23.0 +/- 5.2; week 3 = 13.4 +/- 4.8; week 6 = 12.1 +/- 6.8 nmol.L-1; P < or = 0.05). These data indicate that the GH and catecholamine response to a constant-load exercise stimulus are reduced within the first 3 wk of exercise training and support the hypothesis that a critical threshold of exercise intensity must be reached to stimulate GH release.
Collapse
Affiliation(s)
- A Weltman
- Department of Human Services, Curry School of Education, Charlottesville, VA, USA
| | | | | | | | | | | | | |
Collapse
|
22
|
Davis SE, Mulcahey MJ, Betz RR, Smith BT, Weiss AA. Outcomes of upper-extremity tendon transfers and functional electrical stimulation in an adolescent with C-5 tetraplegia. Am J Occup Ther 1997; 51:307-12. [PMID: 9085730 DOI: 10.5014/ajot.51.4.307] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Affiliation(s)
- S E Davis
- Shriners Hospitals for Children, Philadelphia, Pennsylvania 19152, USA
| | | | | | | | | |
Collapse
|
23
|
Abstract
We examined the redundancy and incremental validity of the newly introduced Million Clinical Multiaxial Inventory-III (MCMI-III) Depressive Personality scale with a heterogeneous sample of 283 psychiatric inpatients. Linear and nominal bivariate correlations indicated sizable overlap between the MCMI-III Depressive, Avoidant, and Self-Defeating Personality scales. Also, the Depressive Personality scale showed moderate overlap with the MCMI-III Major Depression scale. Despite this redundancy, the Depressive Personality scale made significant independent contributions in predicting Axis-I measures of depression, i.e., the Brief Symptom Inventory (BSI) Depression and Interpersonal Sensitivity scales, as well as the MCMI-III Major Depression scale. The Depressive Personality scale appears to be dimensionally related to these measures of Axis-I depression.
Collapse
Affiliation(s)
- S E Davis
- Prairie View, Inc., Newton, KS 67114, USA
| | | |
Collapse
|
24
|
Levy ML, Davis SE, Mccomb JG, Apuzzo ML. Economic, ethical, and outcome-based decisions regarding aggressive surgical management in patients with penetrating craniocerebral injury. J Health Commun 1996; 1:301-308. [PMID: 10947366 DOI: 10.1080/108107396128077] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Each year fatalities in the United States increase as a result of gunshot wounds to the head. This increase, coupled with the progressive limitation of medical and economic resources available at major trauma centers, has brought into question the concept that everything possible should be done to save the lives of victims, who have only a minimal and nonpredictable chance of having a good outcome. Thus, consideration must be given to the economics of treating cranial gunshot wounds and the relationship of this treatment to outcome. When a good outcome can be predicted, treatment should be aggressive. However, when a good outcome cannot be predicted, surgical intervention will have no effect and the potential costs of aggressive treatment must also be considered. Clearly, there are ethical dilemmas involved in withholding operative treatment from any individual, even if there is only a minimal chance of a reasonable neurologic recovery. A negotiation-based approach should be used in determining the medical and ethical benefits of aggressive management strategies. Unfortunately, the care of critically ill patients is inconsistent with this approach. In order to insure that the best decision is made, guidelines dictating when to surgically intervene must be made an essential part of the patient/health care provider negotiation--even in worst case scenarios. The combination of an extremely poor prognosis for these injuries, and economic constraints faced by government-run facilities today could suggest that some patients should be allowed to die. Thus, the physician must be a source of information for the families, providing support and becoming a decision-making partner regarding potential intervention. In each situation, a strict set of guidelines must be formulated to establish a moral foundation for the ultimate mutual decision.
Collapse
Affiliation(s)
- M L Levy
- Department of Neurological Surgery, University of Southern California School of Medicine, Los Angeles, USA
| | | | | | | |
Collapse
|
25
|
Womack CJ, Davis SE, Blumer JL, Barrett E, Weltman AL, Gaesser GA. Slow component of O2 uptake during heavy exercise: adaptation to endurance training. J Appl Physiol (1985) 1995; 79:838-45. [PMID: 8567526 DOI: 10.1152/jappl.1995.79.3.838] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Seven untrained male subjects [age 25.6 +/- 1.5 (SE) yr, peak O2 uptake (VO2) 3.20 +/- 0.19 l/min] trained on a cycle ergometer 4 days/wk for 6 wk, with the absolute training workload held constant for the duration of training. Before and at the end of each week of training, the subjects performed 20 min of constant-power exercise at a power designed to elicit a pronounced slow component of VO2 (end-exercise VO2-VO2 at minute 3 of exercise) in the pretraining session. An additional 20-min exercise bout was performed after training at this same absolute power output during which epinephrine (Epi) was infused at a rate of 100 ng.kg-1.min-1 between minutes 10 and 20. After 2 wk of training, significant decreases in VO2 slow component, end-exercise VO2, blood lactate ([La-] and glucose concentrations, plasma Epi ([Epi]) and norepinephrine concentrations, ventilation (VE), and heart rate (HR) were observed (P < 0.05). Although the rapid attenuation of the VO2 slow component coincided temporally with reductions in plasma [Epi], blood [La-], and VE, the infusion of Epi after training significantly increased plasma [Epi] (delta 2.22 ng/ml), blood [La-] (delta 2.4 mmol/l) and VE (delta 10.0 l/min) without any change in exercise VO2. We therefore conclude that diminution of the VO2 slow component with training is attributable to factors other than the reduction in plasma [Epi], blood [La-] and VE.
Collapse
Affiliation(s)
- C J Womack
- Exercise Physiology Laboratory, University of Virginia, Charlottesville 22903, USA
| | | | | | | | | | | |
Collapse
|
26
|
Hinds PS, Puckett P, Donohoe M, Milligan M, Payne K, Phipps S, Davis SE, Martin GA. The impact of a grief workshop for pediatric oncology nurses on their grief and perceived stress. J Pediatr Nurs 1994; 9:388-97. [PMID: 7837057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Coping with the death of a pediatric patient with whom the nurses has developed a close relationship is reported by nurses as the most stressful experience of being a pediatric nurse. Such losses are inevitable for a pediatric nurse regardless of subspecialty and can contribute to a nurse leaving the specialty or the discipline. To prevent those consequences, nurses' grief needs to be acknowledged, and their grieving needs to be facilitated. The purpose of this study was to determine the impact of a grief workshop on grief symptoms and perceived stress in two groups of pediatric oncology nurses who differed in years of experience in the specialty. Study findings indicated that the workshop affected the two groups differently, with the more experienced nurses reporting significantly higher stress levels after the workshop than did the less experienced nurses. Study findings are interpreted and recommendations for future work are offered.
Collapse
Affiliation(s)
- P S Hinds
- Department of Nursing, St. Jude Children's Research Hospital, Memphis, TN 38101-0318
| | | | | | | | | | | | | | | |
Collapse
|
27
|
Gaesser GA, Davis SE, Blumer J, Barrett E, Weltman A, Womack CJ. 20 EFFECTS OF TRAINING AND EPINEPHRINE INFUSION ON OXYGEN UPTAKE DURING HEAVY EXERCISE. Med Sci Sports Exerc 1994. [DOI: 10.1249/00005768-199405001-00021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
28
|
Weltman A, Weltman JY, Womack CJ, Davis SE, Gaesser GA, Hartman ML. 126 EFFECTS OF TRAINING ON THE GROWTH HORMONE (GH) RESPONSE TO CONSTANT-LOAD EXERCISE. Med Sci Sports Exerc 1994. [DOI: 10.1249/00005768-199405001-00127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
29
|
Davis SE, Womack CJ, Gutgesell M, Barrett E, Weltman A, Gaesser GA. 1166 EFFECTS OF ß-BLOCKADE ON SLOW COMPONENT (SC) OF &OV0312;O2 DURING MODERATE AND HEAVY EXERCISE. Med Sci Sports Exerc 1994. [DOI: 10.1249/00005768-199405001-01168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
30
|
Weltman A, Wood CM, Womack CJ, Davis SE, Blumer JL, Alvarez J, Sauer K, Gaesser GA. Catecholamine and blood lactate responses to incremental rowing and running exercise. J Appl Physiol (1985) 1994; 76:1144-9. [PMID: 8005857 DOI: 10.1152/jappl.1994.76.3.1144] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Ten collegiate rowers performed discontinuous incremental exercise to their tolerable limit on two occasions: once on a rowing ergometer and once on a treadmill. Ventilation and pulmonary gas exchange were monitored continuously, and blood was sampled from a venous catheter located in the back of the hand or forearm for determination of blood lactate ([La]) and plasma epinephrine ([Epi]) and norepinephrine ([NE]) concentrations. Thresholds for lactate (LT), epinephrine (Epi-T), and norepinephrine (NE-T) were determined for each subject under each condition and defined as breakpoints when plotted as a function of O2 uptake (VO2). For running, LT (3.76 +/- 0.18 l/min) was lower (P < 0.05) than Epi-T (4.35 +/- 0.14 l/min) and NE-T (4.04 +/- 0.19 l/min). For rowing, LT (3.35 +/- 0.16 l/min) was lower (P < 0.05) than Epi-T (3.72 +/- 0.22 l/min) and NE-T (3.70 +/- 0.18 l/min) and was lower (P < 0.05) than LT for running. Within each mode of exercise, Epi-T and NE-T did not differ. Because LT occurred at a significantly lower VO2 than either Epi-T or NE-T, we conclude that catecholamine thresholds, per se, were not the cause of LT. However, for both modes of exercise LT occurred at a plasma [Epi] of approximately 200-250 pg/ml (rowing, 221 +/- 48 pg/ml; running, 245 +/- 45 pg/ml); these concentrations are consistent with the plasma [Epi] reported necessary for eliciting increments in blood [La] during Epi infusion at rest. Plasma [NE] at LT differed significantly between modes (rowing, 820 +/- 127 pg/ml; running, 1,712 +/- 217 pg/ml).(ABSTRACT TRUNCATED AT 250 WORDS)
Collapse
Affiliation(s)
- A Weltman
- Exercise Physiology Laboratory, Curry School of Education, University of Virginia, Charlottesville 22903
| | | | | | | | | | | | | | | |
Collapse
|
31
|
Abstract
The purpose of our study was to determine the effects of severe obesity on the foot mechanics of adult females. Twenty-nine adult females between the ages of 20 and 48 years volunteered as subjects for this investigation. The subjects were separated into a severely obese (O) group (body mass index = 41.14 +/- 2.61; N = 16) and a normal weight control group (body mass index = 20.84 +/- 0.47; N = 13). A Locam camera (100 Hz) positioned perpendicular to the subjects' posterior aspect was used to film the rearfoot movement of the subjects during the final 15 sec of a 10 min treadmill walk. The O group had a significantly greater touchdown angle (P = .05), more total eversion range of motion (P = .001), and a faster maximum eversion velocity (P < .001). Moreover, analysis of dynamic foot angles indicated that the O group had significantly (P = .003) more forefoot abduction. Finally, anthropometric data revealed statistically different (P < .001) Q angle measurements between the O and control groups. The results of this study suggest that severely obese females have significantly greater rearfoot motion, foot angle, and Q angle values than normal weight females.
Collapse
Affiliation(s)
- S P Messier
- J. B. Snow Biomechanics Laboratory, Department of Health and Sport Science, Wake Forest University, Winston-Salem, North Carolina 27109
| | | | | | | | | | | |
Collapse
|
32
|
Abstract
Previous investigations have shown blacks to have a significantly lower resting heart rate (HR) compared with whites. Our purpose was to determine if this difference exists during submaximal exercise and to compare other cardiovascular responses during submaximal exercise in black and white males. Sixteen black and 16 white males matched on age, body surface area, and maximal O2 consumption exercised at 0, 50, and 100 W on a cycle ergometer. HR, O2 consumption, and cardiac output via CO2 rebreathing were measured at rest and at each work rate. Stroke volume was then calculated. O2 consumption was not significantly different between blacks and whites at rest or at work rates of 0, 50, or 100 W. Cardiac output increased from rest with 0, 50, and 100 W work for both blacks and whites (6.1 to 13.0, 14.4, and 16.9 l/min and 5.7 to 12.2, 14.3, and 16.3 l/min, respectively). The differences in cardiac output between blacks and whites at rest and all work rates were not statistically significant. At rest and work rates of 0, 50, and 100 W, HR was significantly lower in blacks compared with whites (71, 99, 108, and 119 beats/min vs. 80, 107, 114, and 127 beats/min, respectively). The lower HR in blacks compared with whites was accompanied by a trend toward a higher stroke volume at rest and work rates of 0, 50, and 100 W (85.2, 130.3, 134.7, and 142.9 ml vs. 72.5, 114.9, 126.4, and 127.4 ml, respectively). No differences in resting blood pressures were found.(ABSTRACT TRUNCATED AT 250 WORDS)
Collapse
Affiliation(s)
- M J Berry
- Department of Health and Sport Science, Wake Forest University, Winston-Salem, North Carolina 27109
| | | | | | | | | |
Collapse
|
33
|
Womack CJ, Davis SE, Wood CM, Alvarez J, Sauer K, Weltman A, Gaesser GA. THE BLOOD LACTATE RESPONSE DURING ROWING ERGOMETRY AS A PREDICTOR OF ROWING PERFORMANCE. Med Sci Sports Exerc 1992. [DOI: 10.1249/00005768-199205001-00732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
34
|
Anderson SK, Berry MJ, Davis SE, Downes TR. TWO-DIMENSIONAL ECHOCARDIOGRAPHY VS CO2 REBREATHING FOR ESTIMATING CARDIAC OUTPUT. Med Sci Sports Exerc 1992. [DOI: 10.1249/00005768-199205001-00586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
35
|
Wood CM, Davis SE, Womack CJ, Alvarez J, Sauer K, Gaosser GA, Weltman A. RATINGS OF PERCEIVED EXERTION AND THE BLOOD LACTATE RESPONSE TO EXERCISE IN COMPETITIVE BOWERS. Med Sci Sports Exerc 1992. [DOI: 10.1249/00005768-199205001-00995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
36
|
Sengupta S, Harrigan JT, Rosenberg JC, Davis SE, Knuppel RA. Perinatal outcome following improvement of abnormal umbilical artery velocimetry. Obstet Gynecol 1991; 78:1062-6. [PMID: 1945208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Umbilical artery velocimetry was investigated to determine whether abnormal flow patterns improved with bed rest and if the prognosis of the pregnancy was different in the improved groups. Abnormal flow waveform was defined as a systolic-diastolic ratio (S/D) above the 95th percentile of established normal values. One hundred twenty-eight women had abnormal waveforms. They were placed on bed rest in the left lateral position and monitored by biophysical profile and growth indices. Sixty-six subjects (51.5%) reverted to normal flow waveforms following bed rest, at a mean (+/- SD) interval of 4.5 +/- 1.5 weeks (range 3-10), and 62 (48.5%) exhibited persistent abnormal flow. None of the improved group exhibited fetal distress or perinatal mortality, whereas in the group with persistent abnormal flow, 15 (24%) experienced fetal distress and 13% experienced perinatal mortality. The diagnosis-to-delivery interval in the improved group was 63 +/- 14 days, versus 26 +/- 21 days in the unimproved group, and the mean gestational age at delivery was 37.3 +/- 2.0 versus 32.8 +/- 3.6 weeks, respectively (P less than .0001). We conclude that a subset of patients with abnormal Doppler velocimetry findings will improve on bed rest and have a better perinatal outcome, whereas persistence of abnormal flow defines a group of patients who are at risk for poor perinatal outcome and who require intensive monitoring and intervention.
Collapse
Affiliation(s)
- S Sengupta
- Department of Obstetrics and Gynecology, University of Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School, New Brunswick
| | | | | | | | | |
Collapse
|
37
|
Gilbert WM, Davis SE, Kaplan C, Pretorius D, Merritt TA, Benirschke K. Morbidity associated with prenatal disruption of the dividing membrane in twin gestations. Obstet Gynecol 1991; 78:623-30. [PMID: 1923165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
We report eight cases of intrauterine rupture of the dividing membranes in diamniotic twin gestations and the resulting perinatal morbidity and mortality. The poor outcomes associated with these intrauterine amniotic ruptures included fetal and neonatal death secondary to cord entanglement, preterm rupture of the membranes, preterm labor and delivery, and amniotic band syndrome. The overall perinatal mortality rate was 44% (seven of 16), and the mean gestational age at delivery was 29 weeks (range 22-34). Possible etiologies for this intrauterine diamniotic rupture include fetal trauma to the dividing membranes, amniocentesis, infection, and developmental disturbances. A new theory is examined to explain the surviving twin's morbidity associated with intrauterine death of the co-twin. This study suggests that intrauterine rupture of diamniotic twin membranes carries a perinatal mortality consistent with that of true monoamniotic gestations and that, in fact, this entity may be more common than previously thought. Finally, a suspected monoamniotic gestation cannot be ruled out by the historic presence of a dividing membrane on previous ultrasound examination.
Collapse
Affiliation(s)
- W M Gilbert
- Department of Reproductive Medicine, University of California, San Diego
| | | | | | | | | | | |
Collapse
|
38
|
Messier SP, Davis SE, Curl WW, Lowery RB, Pack RJ. Etiologic factors associated with patellofemoral pain in runners. Med Sci Sports Exerc 1991; 23:1008-15. [PMID: 1943620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The purpose of this study was to extend our knowledge of running related injuries by determining whether relationships exist between selected anthropometric, biomechanical, muscular strength and endurance, and training variables and runners afflicted with patellofemoral pain (PFP). Specifically, the objectives of this study were to examine differences in selected measures between a non-injured control group (C) of runners (N = 20) and a group of injured runners (INJ) diagnosed by an orthopedic surgeon as having PFP (N = 16). High speed photography, a force platform, and isokinetic dynamometry were used to determine rearfoot motion, ground reaction forces, and knee muscular strength and endurance. Stepwise discriminant function analyses were performed on the anthropometric, biomechanical, and muscular strength and endurance variables. Q angle was a significant discriminator (P less than 0.01) between the INJ and C groups. The muscular endurance data revealed several significant discriminators with the INJ subjects being weaker in knee extension endurance. Kinetic analysis revealed several significant discriminators whereas rearfoot movement variables were not good discriminators between the groups. The training data revealed that the INJ group ran significantly less (P less than 0.01) miles.wk-1 than the C group. Our results suggest that Q angle is a strong discriminator between runners afflicted with PFP and non-injured runners. In addition, several muscular endurance and kinetic variables may also be important components of the etiology of PFP.
Collapse
Affiliation(s)
- S P Messier
- J. B. Snow Biomechanics Laboratory, Department of Health and Sport Science, Bowman Gray School of Medicine, Wake Forest University, Winston-Salem, NC 27109
| | | | | | | | | |
Collapse
|
39
|
McCann JC, Davis SE, Trainor DJ, Waller DK, Greenblatt RB. Restructuring support staff classification levels for academic health sciences library positions. Bull Med Libr Assoc 1990; 78:293-301. [PMID: 2393758 PMCID: PMC225408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Nonprofessional library support staff traditionally hold what are considered to be low-paying, nonchallenging positions. These negative factors make retaining creative and productive employees difficult. This article outlines the approach taken at the Medical College of Georgia's Robert B. Greenblatt, M.D. Library to devise a structure of library staff positions that becomes progressively more demanding. A new nine-level Library Staff Classification Plan resulted. This plan also enables and encourages employees to acquire more skills and to accept more responsibility in order to qualify for higher-level library positions or to advance their present position to receive comparable rewards. The plan expresses the level of responsibilities expected, the employee qualifications desired, and lists representative duties across the spectrum of typical library tasks.
Collapse
Affiliation(s)
- J C McCann
- Serials Services Department, Medical College of Georgia, Augusta 30912
| | | | | | | | | |
Collapse
|
40
|
Messier SP, Davis SE, Curl WW, Lowery RB, Pack RJ, Snow JB. 239 ETIOLOGIC FACTORS ASSOCIATED WITH PATELLOFEMORAL PAIN IN RUNNERS. Med Sci Sports Exerc 1990. [DOI: 10.1249/00005768-199004000-00239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
41
|
Davis SE. Pro-choice: a new militancy. Hastings Cent Rep 1989; 19:32-3. [PMID: 2606658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
|
42
|
|
43
|
Davis SE, Rauckman BS, Chan JH, Roth B. 2,4-Diamino-5-benzylpyrimidines and analogues as antibacterial agents. 11. Quinolylmethyl analogues with basic substituents conveying specificity. J Med Chem 1989; 32:1936-42. [PMID: 2502633 DOI: 10.1021/jm00128a041] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A series of nine 2,4-diamino-5-[6-( or 7-)quinolylmethyl]pyrimidines has been prepared by condensations of quinolinecarboxaldehydes with beta-anilinopropionitriles, followed by treatment with guanidine. All compounds has basic or methoxy substituents at the 2- or 4-positions of the quinoline ring. All of the 6-quinolylmethyl derivatives were highly inhibitory against Escherichia coli dihydrofolate reductase (DHFR), provided that an 8-substituent was present in the quinoline ring. Those compounds that had basic substituents in the 2-position of the quinoline ring were also highly specific for bacterial dihydrofolate DHFR, relative to a vertebrate counterpart. Protonation on the quinoline ring nitrogen is a possible cause of specificity.
Collapse
Affiliation(s)
- S E Davis
- Wellcome Research Laboratories, Research Triangle Park, North Carolina 27709
| | | | | | | |
Collapse
|
44
|
Davis SE. A professional recognition system using peer review. J Nurs Adm 1987; 17:34-8. [PMID: 3668674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The concept of a Professional Recognition System or a Clinical Ladder is not new. In fact, many models appear in the literature and have been implemented in hospitals across the country. However, few models contain the element of peer review. This article describes the development process, structure, and function of a Clinical Ladder program at a pediatric tertiary level hospital. The program grew out of a desire and recognized need on the part of the professional nursing staff to reward outstanding nursing care. Based on the concept of peer review, it underwent many revisions and revealed many lessons that can be put to use by other persons attempting to implement such a program.
Collapse
Affiliation(s)
- S E Davis
- Department of Pediatric Surgery, Children's Hospital of Los Angeles, California
| |
Collapse
|
45
|
Anderson PA, Davis SE. Nursing peer review: a development process. Nurs Manag (Harrow) 1987; 18:46-8. [PMID: 3642388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
|
46
|
O'Brien WF, Golden SM, Bibro MC, Charkobardi PK, Davis SE, Hemming VG. Short-term responses in neonatal lambs after infusion of group B streptococcal extract. Obstet Gynecol 1985; 65:802-6. [PMID: 3889746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Short-term (0 to 30 minutes) physiologic responses of neonatal lambs infused with a trichloroacetic extract of a type III (strain 878) group B streptococcus (878-TCA) were studied. Bolus injections of 878-TCA were associated with pulmonary hypertension, peripheral arterial hypoxemia, and reductions in circulating white blood cell and platelet counts. These events were associated with a rise in plasma levels of prostaglandins F2 alpha and E and could be prevented by proper treatment with ibuprofen. Continuous infusions of 878-TCA were associated with a dose-dependent rise in systemic and pulmonary arterial pressures and a fall in arterial PO2. During infusion, inhibition of prostaglandin synthesis resulted in a return toward preinfusion values. The authors conclude that venous infusions of extracts of 878-TCA induce significant pulmonary and systemic arterial vascular perturbations in the neonatal lamb and that some of these alterations are associated with the release of prostaglandins or other arachidonic acid metabolites.
Collapse
|
47
|
Abstract
Although gram-negative sepsis is a major cause of neonatal morbidity and mortality, our understanding of endotoxemia in the neonate has been hampered by the lack of experimental models. Previous studies have suggested neonatal hyporesponsiveness to endotoxin. We studied unanesthetized neonatal lambs which had been exposed to the environment prior to study. These animals demonstrated the classic early phase changes of endotoxemia including pulmonary hypertension which was dependent upon prostanoid production. This model allows further studies of endotoxemia in the neonate.
Collapse
|
48
|
Golden SM, Petit N, Mapes T, Davis SE, Monaghan WP. Bacteriologic assessment of autologous cord blood for neonatal transfusion. Am J Obstet Gynecol 1984; 149:907-8. [PMID: 6465260 DOI: 10.1016/0002-9378(84)90616-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
|
49
|
Davis SE, Lewis SA. Managing scoliosis: fashions for the body and mind. MCN Am J Matern Child Nurs 1984; 9:186-7. [PMID: 6425596 DOI: 10.1097/00005721-198405000-00010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
|
50
|
Abstract
During vaginal delivery, the fetus is exposed to a variety of stresses including pressure applied to the fetal skull. In order to study the effects of this stress on fetal homeostasis, we monitored the response to external cephalic compression applied to the acutely prepared near-term fetal lamb. In response to cephalic pressure, we noted initial bradycardia followed by sustained tachycardia. Mean arterial pressure and pulse pressure rose during cephalic pressure and gradually returned to baseline levels. Cerebral blood flow fell approximately 95% early in the period of compression. This fall in total cerebral blood flow was accompanied by a redistribution of cerebral flow. During this time, a smaller percentage of cerebral blood flow was found in the cortex and a greater percentage was directed to the brainstem.
Collapse
|