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At least 829 records · Page 46Linked to original sources
PubMed2004

A simple position to provide better imaging of upper ureteral stones close to the crista iliaca during extracorporeal shock wave lithotripsy using the Siemens Lithostar.

OBJECTIVE: The fluoroscopic image from the second plan (oblique) tube of an upper ureteral stone close to the crista iliaca may be superimposed on the pelvic bones during SWL using the Siemens Lithostar with the patient in the prone position. This creates difficulty in imaging and targeting of the stone and can necessitate using ureteral catheters before treatment and/or intravenous contrast injection during SWL. We describe a very simple, yet effective method for easier visualization of the stone under this circumstance. METHODS: Between March 1992 and February 2003, we treated 1561 patients with ureteral stones by SWL with the Siemens Lithostar. The stones were localized in the upper ureter in 841. The image of the stone from the second plan (oblique) tube was superimposed on the pelvic bones in 221 in whom visualization of the stone was hardly possible with the standard prone position. By simply rotating the patient 180 degrees on the table, the superimposition of the image of the stone on the pelvic bone was obviated. This resulted in easier and better imaging of the stone during SWL. It also allowed for a clear and superior image to the treating physician during SWL. The energy and shock waves, utilization of anesthesia, number of treatment sessions, auxiliary measures, and complications were noted. Stone load was recorded in square centimeters (cm(2)). Patients were evaluated by intravenous urogram or KUB and ultrasonography when stone-free or CIRF (nonobstructive and noninfectious insignificant fragments < or =4mm) status was noted at the fluoroscopic control 2 to 4 weeks after the last session. Final CIRF decision was made 10-12 weeks after the last session. SWL was regarded as failure if no fragmentation was noted after the 3rd session. Therapy was continued if fragmentation was noted. RESULTS: The median age was 40 (range 5-85). The mean stone burden was 0.8 (range 0.24-2.9) cm(2). No indwelling ureteral stents were placed in any patients before and during treatment. The mean number of shock waves and energy used for the entire patient population was 2007 and 17.5kV, respectively. The median and average treatment session was 1 and 1.7, respectively. A total of 196 patients (89%) were rendered stone-free. Clinically insignificant residual fragments were present in 18 (8%). SWL was unsuccessful in 7 (3%) patients. These stones were removed by ureterorenoscopy. Intravenous contrast administration was not used to facilitate stone targeting during SWL. Anesthesia, in the form of analgesic sedation, was used in 7 (3%) patients. We did not observe any complications and adverse effects. CONCLUSIONS: The technique described hereby does not have an affect on coupling; it only provides a superior image of the stone to the treating physician. We advocate its application in all patients with upper ureteral stones close to the crista iliaca when the fluoroscopic image of the stone from the second plan (oblique) tube is superimposed on pelvic bones during SWL in prone position.

Adolescent↗
PubMed2004

Prone accelerated partial breast irradiation after breast-conserving surgery: preliminary clinical results and dose-volume histogram analysis.

PURPOSE: To report the clinical and dose-volume histogram results of the first 47 patients accrued to a protocol of accelerated partial breast irradiation. Patients were treated in the prone position with three-dimensional conformal radiotherapy after breast-conserving surgery. METHODS AND MATERIALS: Postmenopausal women with Stage T1N0 breast cancer were eligible only after they had first refused to undergo 6 weeks of standard radiotherapy. Planning CT in the prone position was performed on a dedicated table. The postoperative cavity was defined as the clinical target volume, with a 1.5-cm margin added to determine the planning target volume. A total dose of 30 Gy at 6 Gy/fraction was delivered in five fractions within 10 days. RESULTS: The median age of the patients was 67.5 years (range, 51-88 years). The median tumor diameter was 9 mm (range, 1.3-19 mm). In all patients, the prescribed dose encompassed the planning target volume. The mean volume of the ipsilateral breast receiving 100% of the prescription dose was 26% (range, 10-45%), and the mean volume contained within the 50% isodose surface was 47% (range, 23-75%). The lung and heart were spared by treating in the prone position. Acute toxicity was modest, limited mainly to Grade 1-2 erythema. With a median follow-up of 18 months, only Grade 1 late toxicity occurred, and no patient developed local recurrence. CONCLUSION: These data suggest that this approach is well tolerated, with only mild acute side effects and sparing of the heart and lung.

Aged↗
PubMed1999

Craniospinal axis irradiation in children. Treatment in supine position including field verification as a prerequisite for anesthesia without intubation.

PURPOSE: For craniospinal axis irradiation in young children sometimes anesthesia is required. In order to minimize risks from the anesthesist's point of view supine position would be preferable to standard prone position. In case of irradiation in supine position verification of the 3-field junction in the cervical region causes problems, because there is no direct visual control. For such situations the clinical application of a new technique is presented. PATIENTS AND METHODS: For treatment planning a modern 3D planning system was necessary. Patient's positioning was done by using a vacuum-form body immobilizer and an integrated head mask. Radiation fields were placed only by table movements being calculated by the planning system in relation to a reference point at the patient's surface. In addition to common verification films specially prepared small films were used for the 3-field junction in the cervical region. These films were placed close to the patient for the whole time of each radiation session being exposed by every radiation field. RESULTS: Two children (age 3 and 5 years, respectively) were irradiated as described. Twenty-eight of those specially prepared films were exposed. Two films (7%) had to be excluded because of inadequate exposure. An overlap of radiation fields was seen on 1 of the 26 remaining films (4%), whereas an unacceptable gap was not found. Acute skin reactions were comparable to those observed in patients being irradiated in standard prone position. CONCLUSION: The presented technique for craniospinal axis irradiation in supine position including field verification was not only precise and reproducable, but also comfortable and safe for the patient. We suggest it as a new option for craniospinal axis irradiation in children.

Anesthesia, General↗
PubMed2005

Health departments do it better: prenatal care site and prone infant sleep position.

OBJECTIVES: Reduction of prone infant sleep position has been the main public health effort to reduce the incidence of Sudden Infant Death Syndrome (SIDS). METHODS: Oregon Pregnancy Risk Assessment Monitoring System (PRAMS) surveys a stratified random sample of women after a live birth. In 1998-1999, 1867 women completed the survey (64.0% unweighted response; 73.5% weighted response). RESULTS: Overall, 9.2% of all women "usually" chose prone infant sleep position, while 24.2% chose side and 66.5% chose supine position. Women receiving care from private physicians or HMOs more often chose prone position (10.6%) than women receiving prenatal care from health department clinics (2.5%), hospital clinics (6.1%) or other sites (8.3%). Compared to health department prenatal clinic patients, private prenatal patients were more likely to choose prone infant sleep position, adjusted odds ratio = 4.78 (95% confidence interval [CI] 1.64-13.92). CONCLUSIONS: Health Department clinics have done a better job than private physicians in educating mothers about putting infants to sleep on their backs. Providers-especially private providers-should continue to stress the importance of supine sleep position for infants.

Data Collection↗
PubMed2004

Ileocecal valve imaging on computed tomographic colonography.

BACKGROUND: The aim of our study was to describe the visualization, normal anatomy, and variations of the ileocecal valve with computed tomographic (CT) colonography to provide information about its optimal imaging. METHODS: We analyzed data in two- and three-dimensional rendering mode in 71 consecutive patients who underwent routine CT colonoscopy followed by conventional colonoscopy for confirmation of the radiologic findings. RESULTS: Complete visualization of the ileocecal valve was better achieved in the supine than in the prone position (82% vs. 62%, respectively); the ileocecal valve appeared in 64% of cases in the supine position when it was invisible in prone position (p < 0.0001). Partial visualization of the ileocecal valve was possible in 94% of cases. The ileocecal valve was of labial type in 76%, papillary type in 21%, and lipomatous in 3% of cases. The orifice was identified in 53% of ileocecal valves; in two cases of cecal carcinoma, the normal ileocecal valve morphology was grossly disrupted. CONCLUSION: The ileocecal valve was at least partly visualized by CT colonoscopy in 94% of cases, more frequently in the supine position. Its most common normal morphology is the labial type. The absence of orifice visualization alone is not a specific sign for neoplasia, but its presence helps distinguish physiologic bulging from neoplasia.

Adult↗
PubMed2000

Partial liquid ventilation shows dose-dependent increase in oxygenation with PEEP and decreases lung injury associated with mechanical ventilation.

PURPOSE: The purpose of this article is to evaluate the effect of positive end-expiratory pressure (PEEP) during partial liquid ventilation (PLV) and to investigate if lung damage associated with mechanical ventilation can be reduced by PLV. MATERIALS AND METHODS: Twenty-two New-Zealand white rabbits were ventilated in pressure-controlled mode maintaining constant tidal volume (10 mL/kg). Lung injury was induced by repeated saline lavage (PaO2 < 100 mm Hg). Two incremental PEEP steps maneuvers (IPSMs) from 2 to 10 cm H2O in 2 cm H2O steps were performed sequentially. The control group received the first IPSM in the supine position and were turned prone for the second IPSM. In the PLV group (n = 7), 12 mL/kg of perfluorodecalin was instilled after lung injury before the two IPSMs. The early prone group (n = 7) received both IPSMs in the prone position. Parameters of gas exchange, lung mechanics, and hemodynamics as well as pathology were examined. RESULTS: During the first IPSM, the PLV group showed a significant increase in PaO2 after instillation of perfluorodecalin (P < .05) and then showed a dose-dependent increase in PaO2 with PEER. The control and EP groups showed improvement in PaO2 only at higher PEEP, eventually showing no intergroup differences at PEEP of 10 cm H2O. During the second IPSM only the PLV group retained its ability to increase PaO2 to the level obtained during the first IPSM (P < .05 compared with control and EP groups). During the first IPSM all three groups showed increasing trend in static compliance (Cst) with PEEP peaking at PEEP of 8 cm H2O. During the second IPSM, only the PLV group showed increase in static compliance with PEEP (P < .05 compared with other groups). Lung histology revealed significantly less hyaline membrane formation in the PLV group (P < .05). CONCLUSION: PLV shows dose-dependent increase in oxygenation with PEEP and may reduce lung damage associated with mechanical ventilation.

Analysis of Variance↗
PubMed1992

Static lung load and posture effects on pulmonary mechanics and comfort in underwater exercise.

Static lung load (SLL), or transrespiratory pressure gradient, imposed by underwater breathing apparatus can affect breathing comfort and mechanics, especially during exertion. We examined the effects of body position and SLL on two factors known to affect or limit exertion: a) tidal flow-volume limitation, i.e., the percentage of the tidal volume that meets the boundary of the maximum expiratory flow-volume curve; and b) breathing discomfort. Eight healthy male scuba divers (28 +/- 4 yr) performed cycle ergometry to exhaustion during immersion in each of four combinations of body position and SLL: upright, prone, +10 cmH2O, -10 cmH2O. SLL was referenced to the sternal notch. Tidal flow-volume limitation was significantly greater with the negative SLL (P less than 0.05). In the prone position, higher expiratory flows were achieved (P less than 0.01) and flow limitation was not significantly increased. Respiratory discomfort was quantified with a psychophysical rating scale and increased significantly as exercise intensity increased (P less than 0.01). No effect of posture or SLL on discomfort was found. We conclude that, although respiratory comfort is unaffected, positive static lung loading and the prone body position minimize adverse changes in respiratory mechanics during exercise in immersion.

Adult↗
PubMedDate not supplied

[Position and sudden death of the infant].

In western countries, the sudden infant death syndrome (SIDS) is the leading cause of mortality in infants under one year of age. In an official statement on prevention from the French Ministry of Health, sleeping in the supine position or on the side is recommended for all infants unaffected by a particular medical condition. This clear restrictive recommendation is based on valid epidemiological data but raises questions in the minds of paediatricians and general practitioners since the most recent recommendations for treatment of gastro-oesophageal reflux indicate that the prone position at a 30 degrees angle is the first preventive measure to be taken. We present here an objective view point on this complex problem which others may find helpful in developing a sound approach to each individual case. First it must be emphasized that multiple factors are involved in SIDS. While the confirmed correlation between the supine sleeping position and reduced incidence of SIDS is a valid rationale for population-based preventive measures, it does not indicate any causal relationship. Secondly, epidemiological data is valid for a given geographical area but cannot be extrapolated to other areas without taking into account intercurrent factors such as soft bedding, use of feather-bed quilts, excessive bedroom temperature and passive smoking. The public campaign for the prevention of SIDS should be encouraged as an effective low-cost measure, but both physicians and parents should be aware of its multifactorial nature in order to avoid psychologically catastrophic consequences of the guilt syndrome. For infants with uncomplicated simple gastro-oesophageal reflux, a formerly well-known condition but currently less well tolerated by modern parents, it is essential to explain the physiological nature of the reflux to parents then to propose formula thickeners, antacids or prokinetic agents in particularly symtomatic cases. Sleeping in the 30 degrees prone position should not, in this particular case, be introduced as a preventive measure since the risk induced would probably be greater than the beneficial effect. For complicated reflux, after careful exploration and elimination of other causes of vomiting, treatment should be optimized first, followed by discussion on placing the infant in the 30 degrees prone position which should be considered as a therapeutic tool with the same risk of secondary effects as expected with drugs.

France↗
PubMed2005

A comparison of radial artery blood pressure determination between the Vasotrac device and invasive arterial blood pressure monitoring in adolescents undergoing scoliosis surgery.

UNLABELLED: The Vasotrac device (Medwave, Arden Hills, MN) allows noninvasive measurement of arterial blood pressure (BP) and arterial waveform. We have previously demonstrated agreement between the Vasotrac and continuous intraarterial BP monitoring in children with a stable circulation after cardiac surgery in the cardiac intensive care unit. To assess this monitor during different physiologic conditions, we studied the Vasotrac in anesthetized adolescent children undergoing scoliosis surgery in the prone position, with or without controlled hypotension. Eleven children undergoing surgery for idiopathic scoliosis were enrolled in this study. The anesthetic consisted of primarily a nitrous oxide and narcotic technique with controlled hypotension obtained using IV labetalol. Data were analyzed using correlations, mean error, and Bland-Altman plots. Noninvasive BP measured by the Vasotrac correlated closely with intraarterial BP. Waveforms displayed by the two systems were qualitatively similar. Correlation between the two methods for systolic, diastolic and mean BP was r = 0.82, r = 0.83, and r = 0.90, respectively. We conclude that noninvasive BP measurement using the Vasotrac monitor enables near-continuous and reliable monitoring of BP during anesthesia in the prone position and pharmacologic-induced hypotension. IMPLICATIONS: The Vasotrac, a noninvasive arterial blood pressure monitor, performs well in the prone position in adolescent patients undergoing scoliosis surgery using a technique of mild-to-moderate induced hypotension.

Adolescent↗
PubMed2006

[Relationship between globus sensation and esophageal clearance abnormalities in an elderly group].

Recent studies suggest that gastroesophageal reflux disease (GERD) may be a cause of globus sensation. However, it is difficult to examine the reflux of acidic gastric contents directly. We hypothesized that the esophageal clearance capacity against reflux acid may be responsible for the clinical symptoms of GERD. The purpose of this study was to investigate the bolus residue and reflux in the esophagus during swallowing in elderly patients and to discuss the relationship between globus sensation and esophageal clearance abnormalities. Videopharyngoesophageal examinations in the prone position were performed in 156 elderly patients with globus sensation (average age: 74.7 years old). Esophageal clearance in the prone position was classified into 4 subgroups according to the movement of a contrast bolus: Group 1, normal; group 2, retension in esophagus; group 3, reflux of contrast bolus within esophagus; group 4, reflux of contrast bolus into pharyngo-laryngeal regions. Group 1 contained 36 cases (23.1%), group 2 contained 8 cases (5.1%), group 3 contained 79 cases (50.6%), and group 4 contained 33 cases (21.2%). Overall, the reflux of a contrast bolus in the esophagus was observed in 112 cases (71.8%). We concluded that decreased esophageal clearance in elderly subjects affects the defense mechanism against acid exposure and may be a risk factor for the appearance of globus sensation. Videopharyngoesophageal examination in the prone position may be an easy and valuable method for evaluating the function of esophageal clearance.

Aged↗
PubMed1996

Task-dependent effects evoked by foot muscle afferents on leg muscle activity in humans.

The effect of low intensity electrical stimulation of the posterior tibial nerve (PTN) at the ankle on the active triceps surae (TS) muscles was studied in normal subjects, both in a prone position and while standing. PTN stimulation regularly evoked the H-reflex in the flexor digitorum brevis and, in the prone position, a short-latency facilitatory effect in the soleus muscle. During standing, the facilitatory effect was preceded by a clear-cut reduction in electromyograph (EMG) activity. The inhibition-facilitation sequence was evoked in the gastrocnemii under both conditions, on average, though individual differences were present. An EMG modulation similar to that observed under standing conditions was present also in the prone position when subjects pressed the sole of the foot against the wall. Stimulation of sural or digital nerves did not evoke similar effects. It is concluded that foot muscle afferents establish oligosynaptic connections transmitting mixed effects to the TS motoneuronal pool, and that contact with the sole of the foot plays an enabling role for the inhibitory pathway directed to the soleus muscle.

Adult↗
PubMed2003

Unilateral visual loss after cervical spine surgery.

This is a case report of a patient who underwent an uneventful surgery for atlanto-axial dislocation in the prone position, after which he developed painless, unilateral loss of vision in the immediate postoperative period. Based on the ophthalmologic findings a probable diagnosis of ischemic optic neuropathy (ION) was made. Although he recovered his visual acuity completely in 1 month, the visual field defects and color vision abnormalities persisted. Intraoperative anemia, hypotension, with or without vasculopathic risk factors, and prolonged surgery in the prone position have been reported as major risk factors for the development of this complication following spine surgery. However, this healthy young man had an uneventful surgery with no such intraoperative complications. ION in this patient could have been due to a combination of factors, such as a malpositioned horseshoe headrest and surgery performed in the prone position, both of which have the potential to raise the intraocular pressure and lower the perfusion pressure of the optic nerve/nerve head. Variations in the blood supply of the optic nerve due to the presence of watershed zones could be another explanation for this dreaded complication.

Adult↗
PubMed2005

Interactions between sleeping position and feeding on cardiorespiratory activity in preterm infants.

Infants sleeping in the prone position are at greater risk for sudden infant death syndrome (SIDS). Sleep position-dependent changes in cardiorespiratory activity may contribute to this increased risk. Cardiorespiratory activity is also affected by feeding. Twenty prematurely-born infants were studied at 31-36 weeks postconceptional age while sleeping in the prone and supine positions. Heart rate, respiratory rate, and patterns of variability were recorded during interfeed intervals, and effects of position and time after feeding were analyzed by repeated measures analyses of variance. There were significant effects of both sleeping position and time after feeding. Heart rate is higher and heart period variability is lower in the prone position, and the effects of sleeping position on cardiac functioning are more pronounced during the middle of the intrafeed interval. In preterm infants, autonomic responses to nutrient processing modulate the cardiorespiratory effects of sleeping position. Prone sleeping risk may vary with time after feeding.

Electrocardiography↗
PubMed2001

An evidence-based approach to acute respiratory distress syndrome.

We provide an evidence-based approach to managing patients with acute lung injury and acute respiratory distress syndrome (ARDS). We searched MEDLINE and the Cumulative Index to Nursing and Allied Health for randomized trials evaluating lung-protective ventilation strategies, inhaled nitric oxide, prone positioning, and late-phase corticosteroids for managing these patients, and for additional literature related to long-term follow-up of ARDS survivors. The results of our review suggest that pressure- and volume-limited ventilation, according to the ARDS Network protocol, can reduce mortality for patients with acute lung injury, and so may an "open lung" approach to mechanical ventilation. Those 2 strategies are currently being compared in 2 multicenter randomized trials. Although both inhaled nitric oxide therapy and prone positioning can produce dramatic acute improvements in oxygenation for some patients, there is no evidence that these interventions can benefit patients with respect to patient-important outcomes. Therefore it is unreasonable to be dogmatic about the role of inhaled nitric oxide and prone positioning in ARDS. The role of corticosteroids in the late phase of ARDS is unclear and remains a very important unanswered question. With respect to long-term follow-up, we found that pulmonary dysfunction is probably not a major source of morbidity for ARDS survivors, whereas neuropsychological dysfunction is prominent. Ongoing research may suggest interventions to improve the outcome of ARDS and of critical illness in general.

Administration, Inhalation↗
PubMed1999

Effects of ipsilateral anterior thigh soft tissue stretching on passive unilateral straight-leg raise.

STUDY DESIGN: Randomized 3-group pretest-posttest with blind assessment of outcome. OBJECTIVES: The purpose of this study was to examine the effect of sagittal plane hold-relax exercise applied to the ipsilateral anterior thigh, and prone positioning on passive unilateral straight-leg raise measurements. BACKGROUND: Straight-leg raising has been viewed as a measurement for hamstring muscle length, but literature suggests that other structures may affect this measurement. METHODS AND MEASURES: Sixty subjects (45 men, 15 women) qualified for inclusion into the study based on a straight-leg raise measurement of < or = 65 degrees. Subjects were randomly assigned to one of three groups: control, static stretch, or sagittal plane hold-relax exercise. Pretest and posttest straight-leg raise measurements of the right lower extremity were performed for each subject. RESULTS: A 1-way ANOVA of the change scores showed a significant difference between groups. A Tukey post hoc analysis of the change scores showed that both treatment groups' means differed significantly from the control group and from each other, with the sagittal plane hold-relax group exhibiting the largest change (mean of 7.8 degrees +/- 2.8 degrees). CONCLUSIONS: The results of this study show that sagittal plane hold-relax exercise and passive prone results of this study show that sagittal plane hold-relax and passive prone positioning can significantly increase straight-leg raise range of motion, however the sagittal plane hold-relax stretching of the anterior thigh is more effective than passive prone positioning.

Adult↗
PubMed2005

Intraoperative visible bubbling of air may be the first sign of venous air embolism during posterior surgery for scoliosis.

STUDY DESIGN: Case report of two children sustaining venous air embolism (VAE) during posterior surgery for scoliosis. OBJECTIVES: To report 2 cases where visible bubbling at the operative site was the first clinical indication of VAE-induced cardiovascular collapse and to raise the level of consciousness that VAE in the prone position can occur, often with serious consequences. SUMMARY OF BACKGROUND DATA: Twenty-two cases of VAE during surgery for scoliosis in the prone position have been reported. Ten were fatal and ten were in children. Visible bubbling at the operative site was noted in two published cases. METHODS: Retrospective study of 2 cases of VAE at one institution. Clinical, anesthetic, and radiographic features are presented. Details of previously published cases are reviewed and discussed. RESULTS: Both patients were girls with adolescent scoliosis who underwent prone positioned posterior spinal fusion with instrumentation. Visible bubbling of air at the thoracic aspect of the surgical site was noted near the completion of instrumentation and was the first indication of VAE. In both cases, this was clinically recognized and promptly treated. One patient survived normally and the other died. CONCLUSIONS: Visible air bubbling at the operative site may herald the onset of massive VAE during multilevel posterior spinal fusion and instrumentation. A prospective multicenter study using precordial Doppler, central venous catheter, and end-tidal CO2 is recommended to determine the true incidence of VAE in spinal deformity surgery and to evaluate monitoring and treatment methods.

Adolescent↗