Bronchial blocker compared to double-lumen tube for one-lung ventilation during thoracoscopy

BACKGROUND: Video-assisted thoracoscopic surgery (VATS) requires one-lung ventilation with a properly collapsed lung. This study compared the Broncho-Cath double-lumen endotracheal tube with the Wiruthan bronchial blocker to determine the advantages of one device over the other during anaesthesia with one-lung ventilation for thoracoscopy. METHODS: Thirty-five patients undergoing VATS were randomly assigned to one of two groups. Sixteen patients received a left-sided double-lumen tube (DLT) and nineteen a Wiruthan bronchial blocker (BB). The BB group was subdivided in two: BB in the right mainstem bronchus (BBR) for right-sided VATS (9 patients), BB in the left mainstem bronchus (BBL) for left-sided VATS (10 patients). The position of the devices was checked using a fibreoptic bronchoscope. The following variables were measured: 1) number of unsuccessful placement attempts; 2) number of malpositions of the devices; 3) time required to place the device in the correct position; 4) number of secondary dislodgements of the devices after turning the patient into the lateral decubitus position. The quality of lung deflation was evaluated by the surgeons who were blinded to the type of tube being used. RESULTS: The number of unsuccessful placement attempts was one in the DLT group (1/16), three in the BBL group (3/10) and none in the BBR group (0/9). The number of malpositions was significantly greater in the BBL group (10/10) compared to the DLT group (2/16) and to the BBR group (1/9) (P<0.001). The time (mean+/-SD) required to place a BBL was 4.21 min+/-1.28, significantly longer than the time required to place a DLT (2.26 min+/-0.55, P<0.0006) or a BBR (2.41 min+/-0.53, P<0.008). The difference in placement time between DLT and BBR was not significant. The number of secondary dislodgements was one in the DLT group, one in the BBR group and none in the BBL group (NS). The quality of lung deflation was judged excellent or fair in all patients in the DLT and the BBL groups and poor in 44% of the patients in the BBR group. CONCLUSION: It took significantly longer to place a left BB than a DLT (P<0.0006) or a right BB (P<0.008). The number of initial malpositionings of the left BB was significantly greater than in the other groups (P<0.001). The quality of lung deflation was better in the BBL and in the DLT groups than in the BBR group. We conclude that for routine use during left-sided VATS, the use of a DLT is preferable to a left BB because of its greater ease of placement. For right-sided VATS, DLT and right BB showed the same facility of placement but the DLT provided a better quality of lung deflation.     

Time course and dimensions of postural control changes following neuromuscular training in youth field hockey athletes

Purpose

Injury prevention effects of neuromuscular training have been partly attributed to postural control adaptations. Uncertainty exists regarding the magnitude of these adaptations and on how they can be adequately monitored. The objective was to determine the time course of neuromuscular training effects on functional, dynamic and static balance measures.

Methods

Thirty youth (14.9 ± 3 years) field hockey athletes were randomised to an intervention or control group. The intervention included a 20-min neuromuscular warm-up program performed twice weekly for 10 weeks. Balance assessments were performed at baseline, week three, week six and post-intervention. They included the star excursion balance test (SEBT), balance error scoring system (BESS), jump-landing time to stabilization (TTS) and center of pressure (COP) sway velocity during single-leg standing.

Results

No baseline differences were found between groups in demographic data and balance measures. Adherence was at 86 %. All balance measures except the medial–lateral TTS improved significantly over time (p < 0.05) in both groups. Significant group by time interactions were found for the BESS score (p < 0.001). The intervention group showed greater improvements (69.3 ± 10.3 %) after 10 weeks in comparison to controls (31.8 ± 22.1 %). There were no significant group by time interactions in the SEBT, TTS and COP sway velocity.

Conclusions

Neuromuscular training was effective in improving postural control in youth team athletes. However, this effect was not reflected in all balance measures suggesting that the neuromuscular training did not influence all dimensions of postural control. Further studies are needed to confirm the potential of specific warm-up programs to improve postural control.     

Changes in homeostasis during surgical liver resection]

OBJECTIVES: To assess changes in haemostasis during liver resection and to discuss the indications for antifibrinolytic therapy. STUDY DESIGN: Open prospective study. PATIENTS: The study included 39 consecutive non-cirrhotic patients presenting for liver resection under portal triad clamping. METHOD: General anaesthesia was obtained with thiopentone, fentanyl, vecuronium and isoflurane. Transfusion scheme was standardized. Aprotinin (5,000 kIU.kg-1 BW) was administered in case of unexplained bleeding in the operative field. Coagulation pattern was assessed by routine tests and thrombelastrography before surgery, before portal triad clamping, 5 min after reperfusion and at completion of surgery. Patients requiring aprotinin intraoperatively were compared to others. RESULTS: In 32 patients no significant bleeding occurred. Their coagulation pattern was moderately changed and remained within the normal range. In seven patients severe bleeding occurred which was treated with aprotinin. Their coagulation tests were significantly modified, especially after reperfusion, associating an increase in aPTT, TT, FDP, DDim, r + k and a decreased platelet count. CONCLUSION: These changes were more in favour of a dilution coagulopathy or a DIC than hyperfibrinolysis. Therefore substitutive therapy with coagulation factors should be preferred to an antifibrinolytic agent. A systematic administration of the latter for liver resection in non-cirrhotic patients is debatable, considering the allergic risk (reoperation for cancer recurrence), thrombosis facilitation (pedicle clamping) and high cost.     

Thromboxane A2 induces contraction of human prostate smooth muscle by Rho kinase- and calmodulin-dependent mechanisms

Thromboxane A(2) (TXA(2)) induces contraction in different smooth muscle types via its receptor (TXA(2) receptor). However, any motoric role of TXA(2) in prostate smooth muscle tone has not been studied to date. Here, we investigated whether TXA(2) induces contraction of human prostate tissue. After ethical approval, prostate tissue was obtained from 47 patients undergoing radical prostatectomy. Effects of the TXA(2) analogue U46619 ((5Z)-7-[(1R,4S,5S,6R)-6-[(1E,3S)-3-hydroxy-1-octenyl]-2-oxabicyclo[2.2.1]hept-5-yl]-5-heptonic acid) in isolated human prostate strips were studied in organ bath experiments with or without the Rho kinase inhibitor, Y27632 (trans-4-[(1R)-1-aminoethyl]-N-4-pyridinylcyclohexanecarboxamide dihydrochloride), or the calmodulin antagonist W7 (N-(6-aminohexyl)-5-chloro-1-naphtalenesulfonamide hydrochloride). Expression of TXA(2) synthase and TXA(2) receptors were examined by Western blot analysis and immunohistochemistry. Endogenous TXA(2) was quantified by enzyme immunoassay. U46619 induced concentration-dependent contractions of human prostate strips, with a maximum contraction at 3 μM. U46619-induced prostate contraction was significantly inhibited by Y27632 (30 μM) and by W7 (100 μM). TXA(2) synthase and TXA(2) receptors were detected by Western blot analysis. Immunohistochemical stainings showed that expression of TXA(2) synthase in prostate tissue was located to glandular cells, while prostate TXA(2) receptors were located to smooth muscle and glandular cells. The stable TXA(2) metabolite TXB(2) was detected by enzyme immunoassay in the prostate. TXA(2) induces contraction of isolated human prostate tissue by TXA(2) receptor activation. Prostate smooth muscle TXA(2) receptors are coupled to Rho kinase and Ca(2+)-dependent mechanisms. The distribution of TXA(2) synthase and TXA(2) receptors in the human prostate suggests TXA(2)-mediated paracrine epithelial-stromal interactions.     

Validation of the relative 3D orientation of vertebrae reconstructed by bi-planar radiography

The three dimensional (3D) reconstruction of the spine can be obtained by stereoradiographic techniques. To be safely used on a routine clinics basis, stereoradiography must provide both accurate vertebral shape and coherent position. Although the accuracy of the reconstructed morphology of the vertebrae is well documented, only few authors studied the accuracy of the vertebral orientation. Therefore, this paper focuses on the evaluation of the orientation accuracy of the reconstructed vertebrae (obtained by non-stereo corresponding point technique) considering either a 178 point vertebral model or a 6 point vertebral model (previously proposed in the literature). Five dried vertebrae were fixed on holders containing four markers each. The 3D reconstruction of both vertebrae and markers were obtained by stereoradiographic techniques. Using least square method matching from one position to another, the relative orientation was computed for the vertebral models (6 or 178 points) and the four markers. These vertebral and holder orientations were compared (considering the holder's one as reference). The repeatability of these relative orientations (vertebrae and holders) was also evaluated. The mean (RMS) orientation error of 178 point vertebral model was 0.6 degrees (0.8 degrees ), for lateral rotation, 0.7 degrees (1.0 degrees ) for sagittal rotation and 1.4 degrees (1.9 degrees ) for axial rotation. The intra-observer repeatability was 0.5 degrees (0.7 degrees ) for lateral rotation, 0.7 degrees (0.8 degrees ) for sagittal rotation and 0.9 degrees (1.2 degrees ) for axial rotation. The orientation was found more accurate and precise when using the 178 point vertebral model than when using the basic 6 point vertebral model. The relative orientation (in post-operative follow-up with respect to the pre-operative examination) of the vertebrae of one scoliotic patient was performed as an example of clinical application. The stereoradiographic method is a reliable 3D quantitative tool to assess the spine deformity, that can be used in clinics for the follow-up of scoliotic patients.