BACKGROUND: This study was performed to investigate optimal central venous pressure (CVP) or pulmonary artery occlusion pressure (PAOP) transducer levels in supine and prone positions in pediatric patients. METHODS: Chest tomography images of 213 children aged ≤ 10 years were reviewed. Distances from the back to the uppermost blood level of both atria and their ratios to the largest anteroposterior (AP) diameter of the thorax were calculated for the supine position. For the prone position, same distances and ratios were calculated from the anterior chest. Subgroup analysis was performed to evaluate if there were significant differences in each ratio according to age. RESULTS: In the supine position, the ratio of the uppermost blood level of the right atrium (RA) and left atrium (LA) to the largest AP diameter of the thorax was 80–85% and 60–65%, respectively. The ratio of the most posterior blood level of the RA and LA to largest AP diameter of thorax was 45–50% and 55–60%, respectively, from the anterior chest in the prone position. Subgroup differences in each ratio were within the range of 5%. CONCLUSIONS: In pediatric patients, CVP and PAOP transducers should be differently placed according to supine and prone positions. The influence of age was minimal on the level of each transducer.
Central Venous Pressure* ; Child ; Heart Atria ; Humans ; Prone Position* ; Pulmonary Artery* ; Supine Position ; Thorax ; Transducers*

Blast injuries are increasing worldwide from combat and explosions in heavy industry. Primary blast injury is direct injury due to the high pressure effects and pressure differentials of the blast wave itself. Alternating overpressure and underpressure imposed upon tissues of heterogenous densities, particularly air-filled organs. The ear is the first affected organ to primary blast injury because it is the body's most sensitive pressure transducer. Otologic blast injury and tympanic membrane perforation have traditionally been used as a predictor, or biomarker, of occult serious primary blast injury. Hearing loss and tinnitus are the most common ear symptoms. This review details the otologic consequences of blast exposure.
Blast Injuries ; Ear ; Explosions ; Hearing ; Hearing Loss ; Metallurgy ; Tinnitus ; Transducers, Pressure ; Tympanic Membrane Perforation

PURPOSE: Study was conducted to determine and assess the effect of different type of denture adhesives on the incisal bite force of complete denture wearers until the dislodgement of upper denture, using pressure transducer. MATERIALS AND METHODS: 30 patients out of 100 were included in the study. Based on the Kapur's method of scoring denture retention and stability, these patients were divided into 3 groups- Group A - Clinically good dentures; Group B - Clinically fair dentures; and Group C - Clinically poor dentures. A custom made occlusal force meter was constructed based on the load cell type of pressure transducers. Different adhesives (powder, paste and adhesive strips) were used in the study. Complete denture wearers were asked to bite on the load cell and the readings of incisal bite force were recorded. The readings of incisal bite force were subjected to statistical analysis using Repeated measures ANOVA followed by post-hoc bonferroni test. RESULTS: The result suggests that denture adhesives improved the incisal bite force of complete denture wearers significantly The incisal bite force (in kg) in Group A without using adhesives, with powder adhesive, with paste adhesive and with adhesive strips was found to be 2.48 (+/- 0.16), 3.43 (+/- 0.11), 6.01 (+/- 0.11), 3.22 (+/- 0.09) respectively. The incisal bite force (in kg) in Group B without using adhesives, with powder adhesive, with paste adhesive and with adhesive strips was found to be 1.87 (+/- 0.18), 3.35 (+/- 0.14), 5.34 (+/- 0.18), 3.21 (+/- 0.12) respectively. The incisal bite force (in kg) in Group C without using adhesives, with powder adhesive, with paste adhesive and with adhesive strips was found to be 1.00 (+/- 0.17), 3.07 (+/- 0.14), 4.37 (+/- 0.26), 2.99 (+/- 0.14) respectively. CONCLUSION: Within the limitations of the study, it was concluded that the use of denture adhesive was found to be significantly effective in improving the incisal bite force of complete dentures until the dislodgement of upper denture. Fittydent paste adhesive was found to be more effective than the powder and strips adhesives. The improvement in incisal bite force was found to be higher in Group C in comparison to that of Group A and Group B.
Adhesives ; Bite Force ; Bites and Stings ; Denture Retention ; Denture, Complete ; Dentures ; Humans ; Polyvinyls ; Reading ; Transducers, Pressure

OBJECTIVETo develop a type II endoleak porcine model with continuous pressure monitor by the strain-gauge pressure transducer and the patch.

METHODSNine tamed porcine was randomized as the experiment group of 6 domesticated pigs and the control group of 3 domesticated pigs. When the abdominal aortic aneurysm (AAA) was created, the 2(nd) and 3(rd) pair of infrarenal lumber arteries were preserved in the experiment group, while ligated in the control group. The stent-graft was implanted in the endovascular repair. CT angiography was performed to seek endoleak, and the angiography was performed to excluded the type I and type III endoleak. The pressure in the excluded AAA monitored by the strain-gauge pressure transducer was recorded and compared in both groups to evaluated the effect of type II endoleak in the experiment group.

RESULTSThe AAA porcine model with pressure monitor were successfully developed in all 9 porcine. The endoleak and the retrograde flow of the lumber arteries were confirmed by CT angiography in the experiment group. The ratio of the average pressure after the procedure to before the procedure was higher in the experiment group than the control group (U = 0.000, P = 0.020). The ratio of the pulse pressure after the procedure to the average pressure before the procedure was higher in the experiment group than the control group (U = 0.000, P = 0.020).

CONCLUSIONIt is feasible to develop type II endoleak domesticated pig model by preserving the lumber arteries for the retrograde flow, and the AAA model with pressure monitor by the strain-gauge pressure transducer and the patch.

Animals ; Aortic Aneurysm, Abdominal ; surgery ; Blood Vessel Prosthesis Implantation ; Disease Models, Animal ; Endoleak ; Female ; Male ; Manometry ; Stents ; Sus scrofa ; Transducers, Pressure

BACKGROUND/AIMS: It is generally believed that cholecystokinin (CCK) stimulates colonic motility, although there are controversial reports. It has also been suggested that postprandial peptide YY (PYY) release is CCK-dependent. Using a totally isolated, vascularly perfused rat colon, we investigated: (1) the roles of CCK and PYY on colonic motility, (2) to determine if CCK modulates PYY release from the colon to influence the motility and (3) to clarify whether the action of CCK and PYY on colonic motility is mediated via the influence of cholinergic input. METHODS: An isolated whole rat colon was used. Luminal pressure was monitored via microtip catheter pressure transducers from proximal and distal colon. After a control period, CCK-8 or PYY was administerd intraarterially with or without an anti-PYY serum, loxiglumide or atropine at 12, 60 and 240 pM. Each dose was given for a period of 15-minute and the contractile response was expressed as % changes over basal. PYY concentration in the portal effluent was determined by radioimmunoassay. RESULTS: Exogenous CCK-8 increased colonic motility which paralleled the increase in PYY release in the portal effluent. Exogenous PYY also significantly increased colonic motility although it was less potent than CCK. The stimulating effect of CCK-8 was significantly inhibited by an anti-PYY serum, and was completely abolished by loxiglumide, and almost completely abolished by atropine. CONCLUSIONS: CCK increases colonic motility via CCK1 receptor and it is mediated partly by PYY. Cholinergic input is required for the increased motility by either PYY or CCK.
Animals ; Atropine ; Catheters ; Cholecystokinin ; Colon ; Peptide YY ; Phenobarbital ; Proglumide ; Rats ; Sincalide ; Transducers, Pressure

It has been controversial whether upper airway resistance syndrome (UARS) is a distinct syndrome or not since it was reported in 1993. The International Classification of Sleep Disorders classified UARS under obstructive sleep apnea syndrome (OSAS) in 2005. UARS can be diagnosed when the apnea-hypopnea index (AHI) is fewer than 5 events per hour, the simultaneously calculated respiratory disturbance index (RDI) is more than 5 events per hour due to abnormal non-apneic non-hypopneic respiratory events accompanying respiratory effort related arousals (RERAs), and oxygen saturation is greater than 92% at termination of an abnormal breathing event. Although esophageal pressure measurement remains the gold standard for detecting subtle breathing abnormality other than hypopnea and apnea, nasal pressure transducer has been most commonly used. RERAs include phase A2 of cyclical alternating patterns (CAPs) associated with EEG changes. Symptoms of OSAS can overlap with UARS, but chronic insomnia tends to be more common in UARS than in OSAS and clinical symptoms similar with functional somatic syndrome are also more common in UARS. In this journal, diagnostic and clinical differences between UARS and OSAS are reviewed.
Airway Resistance ; Apnea ; Arousal ; Electroencephalography ; Oxygen ; Respiration ; Sleep Apnea, Obstructive ; Sleep Wake Disorders ; Sleep Initiation and Maintenance Disorders ; Transducers, Pressure

PURPOSE: To assess the biomechanical effects and effectiveness of an interspinous spinal spacer (ISS) on the intradiscal pressure using in vitro biomechanical tests. MATERIALS AND METHODS: Six calf spine specimens (less than 2 weeks of age, L1-L5) were divided to two groups the intact and the surgery groups (n=3 each). For the surgery group, an ISS made from PMMA (Greek pi=12-mm) were inserted into the space between the spinous processes of L3-L4. The intradiscal pressures at the various regions of the annulus (anterior, posterior, and posterolateral locations) and the nucleus pulposus were measured using the four pressure transducers under pure compression (700 N) and extension loads (700 N+7.5 Nm). RESULTS: An increase in pressure was observed from neutral to extension at the posterior and posterolateral annulus. After inserting the ISS, the changes in pressure at the adjacent disc levels (L2-L3, L4-L5) were negligible regardless of the loading conditions (p>0.05). However, at the implanted level (L3-L4) statistically significant changes in the pressure were found under extension loading at the nucleus pulposus, posterior and posterolateral regions of the annulus with a pressure drop from 1.48 MPa, 1.42 MPa, 1.71 MPa to 1.11 MPa, 0.961 MPa, 1.08 MPa, at the respective locations (p<0.05). The relative percentage decrease were 25%, 31.7%, and 36.8%. CONCLUSION: On the implanted level, these results showed that the insertion of the ISS with PMMA can effectively reduce the intradiscal pressures by at least 25% quite uniformly over the intravertebral disc during extension. More effective reduction was observed at the posterolateral location. The pressure changes at the adjacent levels were negligible in contrast to the abnormal pressure changes that are frequently reported after conventional rigid fusion. This suggests that the likelihood of adjacent level degeneration after surgery can be minimized using the ISS insertion.
Polymethyl Methacrylate ; Spinal Stenosis* ; Spine ; Transducers, Pressure

BACKGOUND: The accuracy of a disposable blood pressure transducer (DBPT) is determined by its physical properties: natural frequency (NF) and damping coefficient (DC). We planned this study to investigate whether the NF and DC of a DBPT are altered by attaching extended catheters and evaluated changes of these physical properties over time. METHODS: Fifteen DBPT sets were connected to a monitor and recorder set. These sets were divided into three groups; five sets had catheters of normal length (Group 1), five sets had 50 cm extended catheters (Group 2), and five sets had 100 cm extended catheters (Group 3). The NF and DC of each system were measured using the fast flush (FF) test. After the DBPT sets were installed, the FF test was performed for each group at five time intervals: 4, 24, 48, 72, and 96 hours. RESULTS: The NF of Groups 2 and 3 decreased and their DC increased compared to those of Group 1. Whereas the NF of Group 3 increased over time, those of Groups 1 and 2 did not. The DC of Groups 2 and 3 decreased over time, but remained unchanged over time for Group 1. When the FF test was done at intervals longer than 24 hours, it was found that the NF, but not the DC, increased for all groups. CONCLUSIONS: Attention should be paid to interpret blood pressure using DBPTs measured by extended catheters and using DBPTs for long periods of time without FFs.
Blood Pressure ; Catheters* ; Transducers ; Transducers, Pressure*

PURPOSE: The of common carotid artery intima media thickness (IMT) is an acknowledged noninvasive marker for early atherosclerotic changes. We investigate whether common carotid IMT is different between obese and normal-weight children and also evaluate the relationships IMT with cardiovascular risk factors. METHODS: We collected the clinical data (age, sex, pubertal stage, body mass index) and measured blood pressure, glucose, insulin, lipid profiles and adiponectin in 49 obese children (mean age, 12 years) and 24 nonobese children as controls. The control group was composed of 24 nonobese children of the same age, sex and pubertal stage. We measured the carotid IMT of all subjects by B-mode ultrasound with a 7.5-MHz linear transducer and analyzed. RESULTS: Obese children demonstrated a significantly thicker intima media (mean, 0.34 mm, peak, 0.42 mm) compared to the control group (mean, 0.31 mm, peak, 0.38 mm, P<0.01). IMT was significantly correlated to the BMI (r=0.431, P<0.01), age (r=0.317, P<0.01), total cholesterol (r=0.377, P<0.01), triglyceride (r=0.253, P<0.05) and low-density lipoprotein cholesterol (r=0.289, P<0.05). Serum adiponectin was significantly lower in obese children than in controls (11.2 ng/mL vs. 14.7 ng/mL, P<0.05) and negatively related with IMT (r=-0.267, P<0.05). CONCLUSION: Obesity is associated with increased carotid artery IMT in children. Our results suggest vascular changes in obesity seem to occur already in childhood and vascular ultrasonography may helpful for screening cardiovascular complications in obese children.
Adiponectin ; Blood Pressure ; Carotid Arteries* ; Carotid Artery, Common ; Child* ; Cholesterol ; Glucose ; Humans ; Insulin ; Lipoproteins ; Mass Screening ; Obesity ; Risk Factors* ; Transducers ; Triglycerides ; Ultrasonography

PURPOSE: The of common carotid artery intima media thickness (IMT) is an acknowledged noninvasive marker for early atherosclerotic changes. We investigate whether common carotid IMT is different between obese and normal-weight children and also evaluate the relationships IMT with cardiovascular risk factors. METHODS: We collected the clinical data (age, sex, pubertal stage, body mass index) and measured blood pressure, glucose, insulin, lipid profiles and adiponectin in 49 obese children (mean age, 12 years) and 24 nonobese children as controls. The control group was composed of 24 nonobese children of the same age, sex and pubertal stage. We measured the carotid IMT of all subjects by B-mode ultrasound with a 7.5-MHz linear transducer and analyzed. RESULTS: Obese children demonstrated a significantly thicker intima media (mean, 0.34 mm, peak, 0.42 mm) compared to the control group (mean, 0.31 mm, peak, 0.38 mm, P<0.01). IMT was significantly correlated to the BMI (r=0.431, P<0.01), age (r=0.317, P<0.01), total cholesterol (r=0.377, P<0.01), triglyceride (r=0.253, P<0.05) and low-density lipoprotein cholesterol (r=0.289, P<0.05). Serum adiponectin was significantly lower in obese children than in controls (11.2 ng/mL vs. 14.7 ng/mL, P<0.05) and negatively related with IMT (r=-0.267, P<0.05). CONCLUSION: Obesity is associated with increased carotid artery IMT in children. Our results suggest vascular changes in obesity seem to occur already in childhood and vascular ultrasonography may helpful for screening cardiovascular complications in obese children.
Adiponectin ; Blood Pressure ; Carotid Arteries* ; Carotid Artery, Common ; Child* ; Cholesterol ; Glucose ; Humans ; Insulin ; Lipoproteins ; Mass Screening ; Obesity ; Risk Factors* ; Transducers ; Triglycerides ; Ultrasonography