ObjectiveTo analyze the pressure change and distribution of the intervertebral disc of upper thoracic spine in vertical pressure and 5° flexion, extension, or lateral bending. MethodsTwelve thoracolumbar spinal specimens were harvested from mini pigs and were divided into 2 groups (n=6). T1, 2, T3, 4, T5, 6, and T7, 8 segments were included in one group, and T2, 3, T4, 5, T6, 7, and T8, 9 segments were included in the other group. The data from both groups represented the complete upper thoracic vertebra data. Biomechanical machine and pressure sensitive film were used to measure the pressure on the vertebral columns under loadings of 100, 150, and 200 N in vertical pressures and 5° flexion, extension, or lateral bending. The pressure change of each intervertebral disc under different loads and in different movement conditions was analyzed. ResultsIn flexion, the anterior annulus pressure of the upper thoracic vertebra increased (P < 0.05), whereas the posterior annulus pressure showed no significant change (P > 0.05) or an increasing trend (P < 0.05). In extension, the anterior annulus pressure of the upper thoracic vertebra decreased (P < 0.05), whereas the posterior annulus pressure decreased (P < 0.05) or had no obvious change (P > 0.05). In lateral bending, the pressure on the concave side of the annulus increased significantly (P < 0.05). ConclusionThe upper thoracic vertebra has unique biomechanical characteristics under different loadings; moreover, the posterior vertebral structure plays an important role in the movement of the upper thoracic vertebral segment and pressure distribution. In lateral bending of the upper thoracic vertebra, the concave side pressure will increase significantly, which suggests that asymmetrical force is an important cause of scoliosis progression. Gravity plays an important role in the progression of scoliosis.
Objective To investigate the current status of randomized controlled trials (RCTs) and clinical controlled trials (CCTs) on pressure sore in China. Methods We searched Chinese Journal of Nursing, Chinese Journal of Practical Nursing and Journal of Nurses Training in CNKI and VIP (January 2000 to December 2005) for Chinese articles on pressure sore, using "pressure sore", "bed sore", "nursing", "treatment", "prevention", "evaluation" and "management" as search terms. The retrieved articles were summarized. Results We identified 16 reports (10 RCTs and 6 CCTs). The studies were judged to be of low quality.There was one study on the evaluation, two on the prevention, and 13 on the treatment of pressure sores. Conclusion The current studies on pressure sore in China are focusing on treatment. Randomized controlled trials of large sample size of pressure sore are needed to improve nursing quality.
ObjectiveTo investigate the clinical effectiveness of high-glucose insulin mixture on the local treatment of patients with grade Ⅱ and Ⅲ pressure ulcers. MethodsA total of 124 patients with grade Ⅱ and Ⅲ pressure ulcers treated between January 2011 and June 2012 were randomly divided into three groups: saline group (group A, n=41), high-glucose insulin mixture group (group B, n=41) and modern dressing group (group C, n=42). We observed and compared the treatment effects among the three groups using both measurements of traditional evaluation criteria and pressure ulcer scale for healing (PUSH) after a week of dressing. ResultsThe overall treatment effects among the three groups were significantly different (χ2=30.453, P<0.001). The results of pairwise comparisons was that the treatment effect was significantly different between group B or C and group A (P<0.01), but the treatment effect was not statistically different between group B and C (P>0.05). Subgroup analysis for patients with grade Ⅱ or Ⅲ pressure ulcers also came to the similar results. ConclusionBoth high-glucose insulin mixture and modern dressing have significant effects on patients with grade Ⅱ and Ⅲ pressure ulcers. However, the high-glucose insulin mixture costs less and is worthy of extensive promotion.
Objective To quantitatively evaluate the effect of 2 types of pressures induced injury by using threedimensional (3D) reconstruction of rats loaded tibial is anterior muscle from two-dimensional (2D) image of serial histological sections. Methods Twenty female or male Sprague Dawley rats, aged 10-12 weeks and weighing 280-300 g, were randomlydivided into experimental group (n=10) and control group (n=10). The random side of tibial is anterior muscle was givenintermittent gradient (8.0-21.3 kPa) and sustained (13.3 kPa) pressure in 0.12 cm2 area in experimental group and controlgroup, respectively; the experiment was terminated and the general condition of rats was observed after 3 cycles, and a single cycle included 2 hours of compression and 30 minutes of release. The general observations of pressed skin and tibial is anterior muscle were done after 24 hours of pressure rel ief, and the tibial is anterior muscle was harvested integrally from the loaded side, then made into interval 4 μm serial sections. After HE staining, 2D images were obtained. Necrosis and injury areas were distinguished by Image Pro Plus (IPP) 6.0 software and image registration was conducted by Photoshop 8.0.1 after 2D panorama images acquired by digital microscope (× 40) and IPP mosaic software. 3D reconstruction was establ ished via data processing using Mimics 10.1 software so as to get the volume, the surface area, and 3D images of the whole piece of tibial is anterior muscle and injury areas respectively. Results All rats of 2 groups survived till experiment terminated and no skin ulcers occurred after 24 hours. Edema and indentation were observed on press side skin and tibial is anterior muscles of 2 groups, fadeless maroon area was observed in control group. A total of 994 sl ices were obtained from 20 samples of tibial is anterior muscles. 3D images suggested that injury of control group was severe, which penetrated the whole piece of tibial is anterior muscle and expandedalong the tibia bony prominence. By contrast, injury of experimental group was less, but had similar width to the contact surface of indentor. There was no significant difference in the volume and the surface area of tibial is anterior muscle between 2 groups (P gt; 0.05), while the injury volume and the injury surface area were significantly smaller in experimental group than in control group (P lt; 0.05). Conclusion 3D reconstruction is an effective method to quantitatively evaluate pathological changes inside the integrity tissue and can provide the visual basis for the mechanical property distributed in the loaded muscle. Intermittent gradient pressure can reduce deep tissue injury.
Objective To observe the changes of force bearing area and pressures of the rabbit tibiofemoral contact area and the biomechanical reconstruction level of joint after meniscal allograft. Methods A total of 28 Japanese rabbits were involved, weighing 3.0-3.5 kg, male or female. Of 28 rabbits, 7 were selected as meniscus donors, the remaining 21 rabbits were randomized into group A (n=7), group B (n=7), and group C (n=7). Group A underwent single knee opening and suturing, group B underwent medial meniscus excision and suturing, and group C underwent medial meniscus allograft after medial meniscus excision and suturing. The rabbits were sacrified at 12 weeks after operation for biomechanical observation through biomechanical machine and color imaging system. The meniscus tissue specimens were harvested from groups A and C to perform histological and immunohistochemical staining. Results After operation, all rabbits in 3 groups survived to the end of experiment. There were significant differences in the force bearing area and pressures at 0-90° flexion between group B and groups A, C (P lt; 0.05) at 12 weeks, showing no significant difference between group A and group C (P gt; 0.05); and there were significant differences in the force bearing area and pressures at 120° flexion among 3 groups (P lt; 0.05). The histological observation showed that the number of cartilage cells and collagen fibers returned to normal in group C, and the immunohistochemical staining showed that transplanted meniscus of group C contained large amounts of collagen fibers consisting of collagen type I and collagen type II. After 12 weeks of operation, the collagen type I contents were 0.612 5 ± 0.059 8 in group A and 0.587 2 ± 0.063 9 in group C, showing no significant difference (t=0.765, P=0.465); the collagen type II contents were 0.772 4 ± 0.081 5 and 0.814 3 ± 0.051 7, respectively, showing no significant difference (t= —0.136, P=0.894). Conclusion The allograft of rabbit meniscus can significantly increase the force bearing area of the tibiofemoral contact area and reduce the average pressure. Therefore, biomechanically speaking, the meniscus allograft can protect the articular cartilage and reconstruct the biomechanical balance.
Objective To investigate the change law of the intracapsular pressure in vitro without outside force and the pressure of the expander upon the skin soft tissue in vivo during clinical routine expansion so as to provide some references for the safe application of the expander. Methods The rectangle expanders of 50, 80, 100, 150, 200, 250, 300, and 400 mL were used for in vitro expansion at room temperature to 400% volume of the expander capacity. The pressures before and after saline injection were recorded. Twelve patients who needed scar plastic surgery were enrolled; 17 rectangle expanders were implanted in 5 areas (cheek, trunk, forehead and temporal, limb, and head) and expanded routinely. The pressures before and after saline injection were recorded. The pressure of the expander upon the skin soft tissue was calculated and the values of the pressure at 50%, 100%, 150%, and 200% volume of 5 areas were chosen and analyzed statistically. Results The intracapsular pressure of the expanders at different volumes in vitro without outside force during routine expansion before and after saline injection was beyond 0 mm Hg (1 mm Hg=0.133 kPa) at around 100% volume, increased rapidly from 100% to 250% volume, and kept stable from 250% to 400% volume. In vivo, 16 expanders within 200% volume had the maximum pressure before saline injection, 15 had the maximum pressure after saline injection. Before saline injection, the pressure of the expander upon the skin soft tissue was lowest in the cheek, showing significant difference when compared with those of the forehead and temporal and head (P lt; 0.05); the pressure in the trunk was significantly lower than that in the head (P lt; 0.05); and there was no significant difference between the other body sites (P gt; 0.05). After saline injection, the pressure of the expander upon the skin soft tissue was lowest in the cheek, and showed an increasing trend in the trunk, the limb, the forehead and temporal, and the head; no significant difference was found between in the cheek and in the trunk, and between in the forehead and temporal and in the limb (P gt; 0.05), and significant differences were found between the other body sites (P lt; 0.05). Conclusion The pressure of expander upon skin soft tissue at early stage or middle stage is higher than that at late stage during expansion. The pressure is high in the head, and low in the cheek comparatively, and the pressures in the trunk, the forehead and temporal, and the limb are between them.
Objective To explore the effects of changes in the length of the patella on patellofemoral contact areas and pressures, to provide a theoretical foundation for treatment of lower pole of patella fracture. Methods Using homemadeloadingequipment, pressure sensitive films of 100 mm × 100 mm in size were placed on the force platform, vertically downwardload (0-19.6 N) was given. The pressure-sensitive response curve was obtained by computer image analysis of the pressuresensitive tablets and calculation. Six male left fresh knee specimens from voluntary donation were placed in homemade-test fixed load device, and the double-layer pressure sensitive film was placed on the patellofemoral joint surface; under loading of 196 N at flexion of 0, 15, 30, 45, 60, 75, 90, 105, 120, and 135° for 2 minutes, respectively, the pressure sensitive film was removed as the control group. Patellas were transected cut and in situ fixed by Kirschner wire and steel-wire as in situ fixation group. Bone fragments obtained from the corresponding 1/6 and 2/6 of contralateral patella, were embedded in the interspace between osteotomy with internal fixation with Kirschner wire and steel-wire respectively as lengthening group. Followed by the amputating patella length of 1/6, 2/6, 3/6 from proximal to distal and internal fixation with Kirschner wire and steel wire by turns as a shortening group. Repeat the above steps of each experiment. By image analysis the pressure sensitive film, the patella joint contact area were measured, and patellar contact pressure (including the peak pressure and average pressure) was calculated according to pressure-sensitive response curve. Results The actural contact area were significantly smaller in the shortening groups than in the control group at flexion of 30-135° (P lt; 0.05); the pressure was significantly bigger in shortening 1/6 group at flexion of 0, 15, 60, and 75°, in shortening 2/6 group at flexion of 0° and 75-135°, and in shortening 3/6 group at flexion of 0-30°and 75-135° than in the control group (P lt; 0.05); the peak pressure was significantly bigger in shortening 1/6 group at flexion of0, 15, and 60-105°, in shortening 2/6 group at flexion of 0, 15, and 75-105°, and in shortening 3/6 group at flexion of 0, 30, and 60-135° than in the control group (P lt; 0.05). The actural contact area was significantly smaller in the lengthening groups than in the control group at flexion of 15, 60, and 90°, and it was bigger at flexion of 105, 135° in lengthening 2/6 group than in the control group (P lt; 0.05); the pressure was significantly bigger in the lengthening groups at flexion of 15-75° than in the control group and it was smaller in the lengthening groups at flexion of 105, 135°, and smaller in lengthening 2/6 group at flexion of 120° (P lt; 0.05); the peak pressure was significantly smaller in lengthening 1/6 group than in the control group at flexion of 0, 90, and 105° and smaller in lengthening 2/6 group at flexion of 0° (P lt; 0.05). The actural contact area was significantly bigger in all lengthening groups than in all shortening groups at flexion of 30, 45, and 75-135° (P lt; 0.05). The pressure was significantly bigger in shortening 1/6 group than in lengthening groups at flexion of 0, 60, and 90° (P lt; 0.05), in shortening 2/6 group at flexion of 0, 60, and 90-120° (P lt; 0.05), in shortening 3/6 group at flexion of 0-135° (P lt; 0.05). The peak pressure was bigger in shortening groups than in lengthening 1/6 group at flexion of 0, 90, and 105° (P lt; 0.05), bigger than lengthening 2/6 group at flexion of 0° (P lt;0.05余请见正文.....
Objective To compare the effect of two types of intermittent pressure on formation of pressure ulcer in rabbit hind l imbs and to investigate the mechanism of gradually changed intermittent pressure produced by waves bed in the prevention of pressure ulcer. Methods Gracil is (3 cm2) in both hind l imbs of 12 adult Japanese white rabbits were randomlyloaded with gradually changed intermittent pressure (50-160 mm Hg, 1 mm Hg=0.133 kPa) and sustained pressure (100 mmHg) serving as the experimental group and the control group, respectively. The experiment was terminated after 4 cycles, and a single cycle included 2 hours of compression and 30 minutes of compression-release. Blood velocity of hind l imbs and blood perfusion of wound were detected by bidirectional doppler blood flow detector and laser doppler perfusion imaging detection system before compression and at every 10 minutes in compression-release period of each cycle (0, 10, 20 and 30 minutes). After the termination, gross observation of the wound was conducted, pathomorphological changes of tissues from compressed area were observed by HE staining, and contents of NO, malondialdehyde (MDA), and superoxide dismutase (SOD) in muscle tissue were measured using colorimetry method. Results No significant difference was evident between two groups in terms of blood flow velocity before compression (P gt; 0.05); the blood flow velocity of two groups decreased significantly at 0 minute in every compressionrelease period of each cycle, and no significant differences were noted between two groups (P gt; 0.05); the blood flow velocity of theexperimental group was higher than that of the control group at 10, 20 and 30 minutes (P lt; 0.05). No significant difference was noted between two groups in terms of wound blood perfusion before compression (P gt; 0.05); the wound blood perfusion of two groups decreased significantly at 0 minute in every compression-release period of each cycle, and no significant differences were noted between two groups (P gt; 0.05); the difference between two groups was not significant at 10 minutes in the first cycle (P gt; 0.05), and the experimental group was higher than the control group at 20 and 30 minutes in the first cycle (P lt; 0.05). In the following 3 cycles, the recovery of perfusion in the experimental group was faster than that of the control group (P lt; 0.05). Gross observation showed the experimental group had less effusion than the control group. The experimental group had intact cutaneous appendage, less inflammatory cell infiltration, and no obvious ulcer formation, whereas the control group had obvious skin ulcer, depletion of cutaneous appendage, and more inflammatory cells infiltration. Significant differences were noted between two groups in terms of NO, MDA, and SOD content (P lt; 0.05). Conclusion Gradually changed intermittent pressure can maintain the blood perfusion of tissue, reduce ischemia-reperfusion injury and cell apoptosis, and prevent the formation of pressure ulcer.
Objective To investigate the correlation between dynamic intrinsic positive endexpiratory pressure ( PEEPidyn) and volume dependence of elastance and resistance of respiratory system ( Evd/Rvd) derived from nonlinear analysis of respiratory mechanics in COPD patients during pressure support ventilation ( PSV) . Methods Twenty-five COPD patients mechanically ventilated using mode of PSV were ventilated at a PSV level of no less than 20 cm H2O in a period of 15 minutes to attain so-callednear-relaxation state. The pressure( P) , flow( V′) and volume( V) data were analyzed by nonlinear mode of respiratory motion. PEEPidyn was determined by esophageal balloon-tipped catheter technique. The correlations between PEEPidyn and Evd, Rvd as well as Evd ×Rvd were analyzed. Results The correlation coefficients between PEEPidyn and Evd, Rvd as well as Evd ×Rvd were 0. 85,0. 80, and 0. 90, respectively. Conclusions Nonlinear mode of respiratory motion is suitable to analyze respiratory mechanics of COPD patients mechanically ventilated using mode of PSV. There are good correlations between PEEPidyn and Evd,Rvd as well as Evd ×Rvd which may be used to noninvasively monitor PEEPidyn in mechanically ventilated COPD patients using mode of PSV.
Objective To formulate an evidence-based nursing strategy of turning over for a patient with the risk of pressure ulcer. Methods The personalized clinical questions were put forward based on the PICO and patient’s condition, and the following databases such as NGC, The Cochrane Library of DARE, CDSR, CCTR, MEDLINE, PubMed and CBM were searched to collect the best clinical evidences of turning over for preventing pressure ulcer. Results One clinical guideline, one systematic review and three randomized controlled trials were included finally. According to the retrieval outcomes, patient’s clinical condition, and patients and their family members’ willingness, a reasonable nursing plan of turning over was formulated: lie on the visco-elastic foam decompression bed, turn over every 4 hours, and combine supine position with alternation of left-oblique 30° position and right-oblique 30° position. During hospitalization, the grade-I pressure ulcer in size of 4×6 cm2 on patient’s sacrococcygeal region was clear, dry and not broken, and the other part of body with pigmentation had no occurrence of pressure ulcer. Conclusion Evidence-based approaches are helpful to provide patient with a nursing plan that meets the needs of both scientificalness and individualization.