Non-invasive Ventilation: Effect of Vented and Non-vented Exhalation Systems on Inspiratory CO2 and O2 Concentrations,Ventilation, and Breathing Pattern

Introduction

To increase CO₂ elimination and to reduce work of breathing in hypercapnic patients, non-invasive ventilation (NIV) can be applied via mask either with non-vented CO₂ exhalation systems or with vented systems with leak port. The effect of the exhalation system on CO₂ rebreathing in the mask and total gas exchange remains widely unknown. Aim of this study was to compare the exhalation systems in terms of inspiratory O₂ and CO₂ concentrations, breathing patterns and gas exchange.

Methods

We prospectively examined 10 healthy subjects and 10 hypercapnic patients with both exhalation systems. O₂ and CO₂ were measured in the nose, in the mask, and in the ventilation circuit, and respiratory rate, tidal volume, and transcutaneous capnometry (PtcCO₂) were recorded during the experiments.

Results

Using the non-vented system, CO₂ concentrations in the mask were significantly higher in both subject groups, and PtcCO₂ values in the patient group increased up to 3.6 mmHg compared to the vented system (p?=?0.011). O₂ concentrations increased with higher O₂ flow rates, but were significantly lower in the vented settings in both groups. No effect in breathing pattern could be demonstrated during the measurement time.

Conclusion

Using NIV, the chosen exhalation system influences CO₂ and O₂ concentrations under the mask, CO₂ rebreathing from the mask and could influence the effectiveness of the ventilation support with regards to hypercapnia treatment. To compensate for relevant hypoxia, the O₂ supplementation must be set up to a sufficient level under a vented system.

     

Instabilität des distalen Radioulnargelenks

Injuries of the triangular fibrocartilage complex (TFCC) may be fatal to the distal radioulnar joint (DRUJ). This structure is one of the crucial stabilizers and guarantees unrestricted pronosupination of the forearm. A systematic examination is mandatory to diagnose DRUJ instability reliably. A clinical examination in comparison to the contralateral side is obligatory. Plain radiographs are required to exclude osseous lesions or deformities. Computed tomography of both wrists in neutral, pronation and supination is necessary to verify DRUJ instability in ambiguous situations. Based on a systematic examination wrist and DRUJ arthroscopy identify lesions clearly. Injuries of the radioulnar ligaments which entail DRUJ instability, should be reconstructed preferably anatomically. Ulnar-sided TFCC lesions may often cause DRUJ instability. Osseous ligament avulsions are mostly treated osteosynthetically. Ligament tears may be refixated using anchor or transosseous sutures. Tendon transplants are necessary for an anatomical reconstruction in cases of irreparable ruptures.     

STW 5, a phytopharmacon for patients with functional dyspepsia: results of a multicenter, placebo-controlled double-blind study

BACKGROUND: Functional dyspepsia (FD) constitutes a complex picture with a variety of epigastric symptoms. No standard therapy is currently available for FD. OBJECTIVE: This multicenter, placebo-controlled, double-blind study evaluated the efficacy and tolerability of the herbal drug STW 5, mainly comprising a fresh plant extract from Iberis amara. METHODS: Patients with FD were included. Gastrointestinal endoscopy, H. pylori-status, and a 7-day run-in phase were required. A total of 315 patients were treated with 3 x 20 drops/day of either STW 5 or placebo. Symptom assessment: day 0, 2, 4, and 8 wk of treatment. The principal outcome criterion was the change in a validated Gastrointestinal Symptom Score (GIS). Symptom severity was rated using the Likert scale. RESULTS: A total of 315 patients remained in the safety population. Of them, 158 were treated with STW 5 and 157 with placebo. The intention-to-treat population comprised 308 patients. Dropout number was similar in both groups. GIS showed improvement during the treatment period. The STW 5 group improved 6.9+/-4.8 points up to day 56, placebo group by 5.9+/-4.3 (P<0.05). H. pylori did not influence the results. Drug tolerability and safety were similar in both groups. CONCLUSION: This placebo-controlled study with an 8-wk treatment period documents the efficacy of STW 5 in FD.     

Discrepant MR and [18F]Fluoroethyl-L-Tyrosine PET Imaging Findings in a Patient with Bevacizumab Failure

Antiangiogenic treatment using bevacizumab may cause difficulties in distinguishing between antivascular and true antitumor effects when using MRI response criteria based on changes of contrast enhancement (i.e., Macdonald criteria). Furthermore, more precise tumor response assessment criteria (i.e., RANO criteria), which incorporate nonenhancing T2/FLAIR sequences into Macdonald criteria, may be influenced by other causes of T2/FLAIR hyperintensity (e.g., radiation-induced gliosis). The authors present discrepant MR and [¹⁸F]fluoroethyl-L-tyrosine PET imaging findings in a patient with bevacizumab treatment failure.Key Words: Volume-of-interest analysis, Metabolically active tumor volume, Amino acid PET, [¹⁸F]Fluoroethyl-L-tyrosine, RANO criteria     

Surgical correction of deformities of the distal radius due to fractures in pediatric patients

Introduction The indication and treatment of malunited fractures of the distal radius in the growing skeleton differ from those for adults. The literature results are scarce. In this study we examined the results of surgical correction following fractures of the distal radius in infants.Materials and methods Seven infant patients with malaligned fractures of the distal radius that demonstrated significant functional deficit and poor prognosis for spontanous recovery were treated with surgical correction. Two of them were treated because of growth disturbance from post-traumatic closure of the distal radial physis.Results All seven osteotomies healed with acceptable radiologic alignment. After an average follow-up period of 3 years and 1 month (range 10 months to 8 years and 4 months), patients had an average range of wrist motion (ROM) of 131 deg in extension and flexion (93% of the contralateral side, 130% of presurgical situation); 65 deg in ulnar and radial deviation (94% of the contralateral side, 122% of presurgical situation); and 177 deg in pronation and supination of the forearm (97% of the contralateral side, 115% of presurgical situation). The average grip strength of 71.4 kPa was nearly equal to the other side with 72.8 kPa. The average postoperative angulation of the distal radius was 12 (range 10–17) deg, the radial inclination 20 (range 12–30) deg, and the ulnar variance was –0.6 (range –3 to +2) mm. According to the Fernandez point score system as well as the scale of Fernandez, there were five excellent results and two good results. The patients described low disability on the DASH scores, with a median of 4 (range 0–41) points.Conclusions Surgical correction for malunited fractures of the distal radius provides good and excellent radiological and functional results in the growing skeleton. It should be considered immediately if there is poor remodeling capacity and disabling loss of function.     

Severe contracture of the proximal interphalangeal joint in Dupuytren's disease: does capsuloligamentous release improve outcome?

This prospective study assessed whether patients with severe proximal interphalangeal joint contracture (#10878;60 degrees ) due to Dupuytren's disease which persisted after fasciectomy alone benefited from an additional capsuloligamentous release. Forty-three patients with 43 severely contracted proximal interphalangeal joints underwent operative correction followed by a standardized postoperative rehabilitation programme. All were followed for 6 months. In 11 patients correction of the proximal interphalangeal joint to 20 degrees could not be achieved by fasciectomy alone, and an additional capsuloligamentous release was performed which effectively corrected all their residual flexion contractures. There were no statistically significant differences between the capsulotomy and the non-capsulotomy group with respect to the residual proximal interphalangeal joint contracture at the end of surgery, or at their last follow-up examination.     

Corrective osteotomy of the distal radius through volar approach

Operative correction through the malunion has become a well-accepted reconstructive procedure for symptomatic malunited extra-articular fractures of the distal radius over the last 3 decades. Now that newer plates designed specifically for the volar fixation of dorsally unstable distal radius fractures by incorporating buttress pins and screws that lock to the plate are available, more and more surgeons prefer volar fixation of dorsally unstable distal radius fractures. In the mid 1970s, the senior author (U.B.L.) developed a technique for corrective osteotomy of dorsally tilted malunions of the distal radius using a radiovolar approach and a special plate. This technique was proved to be efficient in more than 400 patients.