Advanced life support performance with manual and mechanical chest compressions in a randomized,multicentre manikin study

Aim of the studyClinical mechanical chest compression studies report diverging outcomes. Confounding effects of variability in hands-off fraction (HOF) and timing of necessary tasks during advanced life support (ALS) may contribute to this divergence. Study site variability in these factors coupled to randomization of cardiopulmonary resuscitation (CPR) method was studied during simulated cardiac arrest prior to a multicentre clinical trial.MethodAmbulance personnel from four sites were tested in randomized, simulated cardiac arrest scenarios with manual CPR or load-distributing band CPR (LDB-CPR) on manikins. Primary emphasis was on HOF and time spent before necessary predefined ALS task (ALS milestones). Results are presented as mean differences (confidence interval).ResultsAt the site with lowest HOF during manual CPR, HOF deteriorated with LDB-CPR by 0.06 (0.005, 0.118, p = 0.04), while it improved at the two sites with highest HOF during manual CPR by 0.07 (0.019, 0.112, p = 0.007) and 0.08 (0.004, 0.165, p = 0.042). Initial defibrillation was 29 (3, 55, p = 0.032) s delayed for LDB-CPR vs. manual CPR. Other ALS milestones trended toward earlier completion with LDB-CPR; only significant for intravenous access, mean difference 70 (24, 115, p = 0.003) s.ConclusionIn this manikin study, HOF for manual vs. mechanical chest compressions varied between sites. Study protocol implementation should be simulation tested before launching multicentre trials, to optimize performance and improve reliability and scientific interpretation.     

Students insert the laryngeal tube quicker and more often successful than the esophageal–tracheal combitube in a manikin

BackgroundEndotracheal intubation remains the standard of airway management. Because intubation skills are difficult to acquire, for medical students teaching of easier to learn techniques should be considered.MethodsWe retrospectively analyzed data that were collected in a University teaching facility. 264 medical students were taught how to use laryngeal tube (LT) and Esophageal Tracheal Combitube^® (ETC) in a manikin. The students underwent one of two different types of extraglottic airway management training consisting of either long lecture (30 min) and intensive training (2 h) (group IT, n = 48), or brief (10 min) lecture and 20 min of training (group BT, n = 216). Both groups underwent a test 6 weeks after training, group IT had an additional test 24 h after training.ResultsAfter 24 h students in group IT were faster using the LT than the ETC (31.7 s ± 2.1 vs. 51.9 s ± 5.8, p < 0.001). Up to 6 weeks after training students were able to place the LT significantly faster than the ETC in both groups (26.5 s ± 2.1 vs. 53.9 s ± 5.8 group IT and 43.4 s ± 1.6 vs. 103.8 s ± 4.4 group BT, p < 0.001). At 24 h and 6 weeks following intensive training, there was no statistical difference in the time required for insertion of either device.ConclusionFollowing different training scenarios in a manikin, students were able to place the LT much faster than the ETC. Even brief training was sufficient to generate short insertion times for the LT.     

Skeletal consequences of familial hypocalciuric hypercalcaemia vs. primary hyperparathyroidism

Objectives Bone metabolism is only superficially described in familiar hypocalciuric hypercalcaemia (FHH). We describe and compare biochemical and osteodensitometric variables in FHH and primary hyperparathyroidism (PHPT) and assess whether they can improve the diagnostic discrimination between the groups. Design Cross‐sectional. Patients Sixty‐six FHH patients with known calcium‐sensing receptor (CASR) gene mutations and 147 PHPT patients. Measurements We determined calcium, creatinine, phosphate, magnesium, parathyroid hormone (PTH), 25OHD, 1,25(OH)₂D and alkaline phosphatase (AP) in plasma, NTx/creatinine ratio in urine and calculated the calcium/creatinine clearance ratio (CCCR). We performed dual energy X‐ray absorptiometry at the lumbar spine, hip, forearm and whole body. Results When compared with normal controls, the FHH patients had increased levels of PTH and AP with normal U‐NTx and regional Z‐scores. Increased phenotypic expression of CASR mutations in terms of hypercalcaemia was associated with higher lumbar spine bone mineral density, but not with bone markers. FHH were younger and leaner than the PHPT patients. They had comparable plasma Ca²⁺ and 25OHD, but lower levels of PTH, 1,25(OH)₂D, AP and U‐NTx. They had higher Z‐scores in the hip and in the forearm. We achieved the best discrimination between groups by multiplying CCCR with AP, 1,25(OH)₂D and PTH, but the difference between the area under the curves by receiver operating characteristic analysis remained insignificant. Conclusion Familiar hypocalciuric hypercalcaemia is associated with increased PTH and AP compared to normal controls, but not with bone loss irrespective of the severity of the CASR mutations. A multiplicative model including CCCR, AP, 1,25(OH)₂D and PTH insignificantly improved the power of the CCCR to differentiate between FHH and PHPT. However, we still recommend CASR gene analysis in patients with a CCCR <0·020.     

Symplastic glomus tumor – a rare but distinct benign histological variant with analogy to other 'ancient' benign skin neoplasms

A 78-year-old woman presented with a nail deformity of the index finger of the left hand associated with paroxysmal pain upon cold exposure. Histologically, a well-circumscribed tumor of 3 mm diameter was found in the dermis. The neoplastic cells in some areas were of pronouncedly variable size and cytomorphology, mostly epithelioid in shape, with eosinophilic cytoplasm and indistinctly defined cell borders. Pronounced nuclear pleomorphism and atypia were striking features, but no mitotic figures were noted. Multinuclear cells were present as were numerous small-to-medium vessels throughout the tumor. The tumor stroma showed myxoid areas.
Immunohistochemistry showed cytoplasmic and membranous expression of smooth muscle actin and vimentin. The histological features and immunoprofile were consistent with the diagnosis of symplastic glomus tumor, a rare histological variant, which has been defined as a glomus tumor exhibiting marked nuclear atypia, in the absence of any other criteria for malignancy. The biological behavior of the tumor is benign. It is essential to differentiate this entity from malignant glomus tumor, which has metastatic potential. Even prominent cellular atypia and nuclear pleomorphism in a glomus tumor as in our case is not a marker of malignancy in the absence of additional criteria.