Prediction model of rhomboid major and pleura depth based on anthropometric features to decrease the risk of pneumothorax during dry needling

Background: Although mostly common adverse events associated to dry needling can be considered minor, serious adverse events including induced pneumothorax cannot be excluded, and safety instructions for reducing the risk of pleura puncture are needed. Objective: To investigate if anthropometric features can predict the rhomboid major muscle and pleura depth in a sample of healthy subjects to avoid the risk of pneumothorax during dry needling. Methods: A diagnostic study was conducted on 59 healthy subjects (52.5 % male) involving a total of 236 measurements (both sides in maximum inspiration and expiration), to calculate the accuracy of a prediction model for both pleura and rhomboid depth, as assessed with ultrasound imaging, based on sex, age, height, weight, body mass index (BMI), breathing and chest circumference. A correlation matrix and a multiple linear regression analyses were used to detect those variables contributing significantly to the variance in both locations. Results: Men showed greater height, weight, BMI, thorax circumference and skin-to-rhomboid, rhomboid-to-pleura y skin-to-pleura distances (p<0.001). Sex, BMI, and thorax circumference explained 51.5% of the variance of the rhomboid (p<0.001) and 69.7% of pleura (p<0.001) depth limit. In general, inserting a maximum length of 19 mm is recommended to reach the deep limit of rhomboid major decreasing the risk of passing through the pleura. Conclusion: This study identified that gender, BMI and thorax circumference can predict both rhomboid and pleura depth, as assessed with ultrasonography, in healthy subjects. Our findings could assist clinicians in the needle length election for avoiding the risk of induced pneumothorax during dry needling.

Improvement in Lung Insufflation in Spontaneously Breathing Tracheostomized Patients by Using a New Pulmonary Expansion Device: A Pilot Study

Lung expansion techniques (LETs) are a key component of pulmonary rehabilitation. Nevertheless, these can be limited in tracheostomized patients because of the infraglottic position of tracheostomy cannulas. We propose a novel pulmonary expansion device (PED) that allows deep inspiration with a postinspiratory pause for a few seconds by means of a unidirectional valve and an occlusion/flow release cap. It is equipped with a relief valve that opens at 60 cm H2O in cases in which this threshold is attained. We aimed to evaluate the impact on lung volume and pressure in spontaneously breathing tracheostomized patients subjected to LETs. A single-arm pilot interventional study was conducted in an adult intensive care unit (ICU), including spontaneously breathing tracheostomized patients. 80 treatments were performed on 10 patients with tracheostomies with PED over a period of 3 months. The maximal inspiratory volume (MIV) was significantly increased by using PED (MIV-PED) at both day 1 (725 (600–820) mL versus 1550 (1250–1700) mL, P &lt; 0.001) and day 3 (870 (750–950) mL versus 1662 (1550–1900) mL, P &lt; 0.001). Inspiratory pause pressure (PIP-PED) did not significantly change from day 1 to day 3 (18 (14–20) cm H2O versus 14 (12–22) cm H2O, P = 0.36). The use of the PED in tracheostomy patients acted as an artificial glottis by performing a novel pulmonary re-expansion maneuver, and increased volumes and intrapulmonary pressure with prolongation of maximum inspiration were achieved.

Rhythmic Breath Holding and Its Effect on Arterial Blood Pressure and Its Correlation With Blood Gases

A single episode of breath-holding (BH) is known to elevate the blood pressure, and regular breathing exercise lowers the blood pressure. This prompted us to investigate how a series of BH epochs would affect the cardiovascular system. To observe arterial blood pressure (ABP) and heart rate (HR) changes associated with a series of “BH epochs” following maximum inspiration and maximum expiration and find the underlying mechanisms for the change by autonomic activity. Thirty-five healthy young adults were instructed to hold their breath repetitively, for 5 minutes, in two patterns, one following maximum inspiration and other following maximum expiration. ABP and ECG (for Heart Rate Variability) were continuously recorded at rest and during both the maneuvers. Capillary blood gases (BG) were zanalyzed at baseline and at the breakpoint of the last epoch of BH. ABP rose significantly at the breakpoint during both the maneuvers. No change in HR was observed. There was significant fall in PO2 from 94.7 (4.1) mmHg at baseline to 79.1 (9.0) mmHg during inspiratory and 76.90 (12.1) mmHg during expiratory BH. Similarly, SPO2 decreased from 96.3 (1.9) % at baseline to 95.4 (1.5) % and 94.5 (2.7) % during inspiratory and expiratory BH, respectively. Rise in PCO2 from 39.5(3.1) mmHg at baseline to 42.9 (2.7) mmHg and 42.1 (2.8) mmHg during inspiratory and expiratory BH respectively was observed. There was no significant correlation between blood gases and arterial blood pressure. Among HRV parameters, a significant decrease in SDNN, RMSSD, HFnu, total power and SD1/SD2 and the significant increase in LFnu, LF/HF and SD2 were observed during both BH patterns. Rhythmic BH patterns affect the cardiovascular system in similar way as a single episode of BH. Sympathetic overactivity could be the postulated mechanism for the same. © 2019 Tehran University of Medical Sciences. All rights reserved. Acta Med Iran 2019;57(8):492-498.

Improved Dynamics of Thoracic Cage and Exercise Capacity after Nuss Repair for Pectus Excavatum

Background Pectus excavatum (PE) reduces the dynamics of the thoracic cage, with a negative impact on exercise capacity. We aimed to evaluate the effects of Nuss repair for PE on the dynamics of the thoracic cage and exercise capacity in adults. Methods This was a prospective observational study of 46 adults (mean age, 26.2 years) who underwent PE correction using the Nuss procedure between September 2016 and August 2017. Cirtometry was used to obtain measures of thoracic cage circumference at two levels (axillary level [AL] and xyphoid level [XL]), at the end points of inspiration and expiration. Circumference measures were obtained before surgery and at 1, 3, and 6 months after surgery. Exercise capacity was also evaluated using the 6-minute walk test (6MWT). The association between the 6MWT data and cirtometry measures was evaluated using Pearson's correlation. Results The circumference at maximum inspiration increased from baseline to 3 months after surgery (p < 0.01), at both the AL (84.5 ± 4.9 vs. 88.5 ± 5.1 cm) and XL (80.1 ± 4.8 vs. 83.7 ± 5.1 cm). The 6MWT also significantly improved from baseline to 3 months after surgical correction (544.7 ± 64.1 vs. 637.3 ± 59.4 m, p < 0.01), with this improvement being correlated to the increase in thoracic circumference on maximal inspiration at both the AL and XL (0.8424 and 0.7951, respectively). Conclusion Improved dynamics of the thoracic cage were achieved after Nuss repair for PE in adults. This increase in thoracic circumference at maximum inspiration was associated with an improvement in exercise capacity at 3 months after surgery.

Performing Chest X-Rays at Inspiration in Uncooperative Children: The Effect of Exercises with a Training Program for Radiology Technicians

Objective. It is difficult to acquire a chest X-ray of a crying infant at maximum inspiration. A computer program was developed for technician training.Method. Video clips of 3 babies were used and the moment of deepest inspiration was determined in the single-frame view. 12 technicians simulated chest radiographs at normal video speed by pushing a button. The computer program stopped the video and calculated the period of time to the optimal instant for a chest X-ray. Demonstration software can be tested at website online. Every technician simulated 10 chest X-rays for each of the 3 video clips. The technicians then spent 40 minutes practicing performing chest X-rays at optimal inspiration. The test was repeated after 5, 20, and 40 minutes of practice.Results. 6 participants showed a significant improvement after exercises (collective 1). Deviation from the optimal instant for taking an X-ray at inspiration decreased from 0.39 to 0.22 s after 40 min of practice. 6 technicians showed no significant improvement (collective 2). Deviation decreased from a low starting value of 0.25 s to 0.21 s.Conclusion. The tested computer program improves the ability of radiology technicians to take a chest X-ray at optimal inspiration in a crying child.

Analysis of the corrective forces exerted by a dynamic derotation brace (DDB)

Background: Discrepancies exist in the current literature for bracing of spinal curvature conditions. This can be explained by the diversity of brace types, the different curve patterns and the various measurement methods and instruments.Objectives: The aim of this study was the analysis of the corrective forces exerted by a dynamic derotation brace (DDB), at the skin-brace interface, altering the strap tension and body posture.Study Design: We analysed the direct forces exerted by a DDB’s main pad, on 44 (38 girls, 6 boys) idiopathic scoliotic patients. Twenty-seven patients had a single right thoracic and 17 a single left or right thoracolumbar curve.Methods: We used the F-Socket 9801 pressure sensor and the MatScan Research BETA STAM 6.30 software, while patients adopted nine different postures. The patients were divided into three different groups: those who wore the brace for the first time, those who were changing their brace for a new one, and those who were having adjustments made to their existing brace.Results: These patients who were having adjustments made to their existing brace caused the highest mean exerted force. Changes in strap tension and body posture resulted in statistically significant alterations of the interface pressure and the forces exerted on the patient’s body.Conclusions: Tightening the brace’s straps always produces a significant force increase, independent of the body posture and the curve type. Also there are some body postures which significantly modify the exerted force. The body posture of maximum inspiration for thoracolumbar curves and, additionally, prone and lying left for thoracic curves.

Effect of lower esophageal sphincter tone and crural diaphragm contraction on distensibility of the gastroesophageal junction in humans

Previous studies of distensibility of the gastroesophageal junction (GEJ) in humans have not tried to distinguish between the effects of muscle action and passive elastic tissue properties of the GEJ. We studied 15 healthy subjects (ages 23–67 yr, 11 men/4 women) by using a catheter with a highly complaint bag positioned manometrically at the GEJ. The bag was distended with air at a rate of 20 ml/min while intrabag pressure was recorded. Distensions were performed during normal breathing, with breath held at maximum inspiration (MI) to activate the diaphragmatic crura, and with midesophageal balloon distension (BD) to relax the lower esophageal sphincter. In 10 subjects, distensions were performed after atropine injection (12 μg/kg iv). Pressure-volume curves and incremental distensibility values were calculated and compared among the different conditions. Both MI and BD significantly altered the slopes of the pressure-volume curves, whereas no effect was seen with atropine. Maximum distensibility was seen at the volume increment of 5–10 ml and was reduced with larger volumes. Distensibility measurements for the various test conditions tended to converge at the largest volume increment, suggesting that distensibility at this degree of distension was more related to the passive elastic properties of the GEJ. On the basis of these findings, we conclude that there can be significant active muscular contributions to recordings of distensibility at the GEJ, variations that must be controlled for during different study conditions.