Tetanus - A case report and literature review

Neðst á síðunni er hægt að nálgast greinina í heild sinni með því að smella á hlekkinn View/Open Allur texti - Full textA 79 year old farmer was referred to the University Hospital with a three days history of difficulty in opening his mouth. On examination, both masseters were seen to be stiff, suggesting tetanus or jaw-subluxation. An attempt to reduce the joint was made, but failed. He subsequently developed progressive respiratory difficulties requiring intubation. The farmer had recently cut his finger on barbed wire. He had not received tetanus immunization for years and it was not clear whether primary immunization had been completed. Tetanus immunoglobulin and antibiotics were administered. He proceeded to develop autonomic instability and critical illness polyneuropathy requiring 45 days of ICU care. He was finally discharged eight months later. The farmer has gradually improved and is now living unaided at home. In this article we will review this case and the literature on tetanus. Correspondence: Albert Pall Sigurdsson, [email protected] Key words: Tetanus, case report.79 ára bónda var vísað á Landspítala þar sem hann hafði ekki getað opnað munninn í þrjá daga. Við skoðun voru tyggingarvöðvar spenntir. Talið var að þetta væri stífkrampi eða los á kjálkaliði. Reynt var að setja hann í lið án árangurs. Síðar bar á öndunarörðugleikum sem ágerðust. Bóndinn fór á gjörgæslu í öndunarvél. Hann hafði stungið sig í fingur á gaddavír við landbúnaðarstörf nokkru áður. Hann hafði ekki fengið stífkrampabólusetningu í mörg ár og óljóst var um grunnbólusetningu. Gefið var stífkrampa-ónæmisglóbúlín og sýklalyf. Síðar fékk hann truflun á ósjálfráða taugakerfinu auk gjörgæslu-úttaugameins. Hann lá 45 daga á gjörgæslu og útskrifaðist heim eftir 8 mánaða legu. Ástandið hefur lagast og er hann nú að mestu leyti sjálfbjarga. Í greininni er farið yfir tilfellið og gefið yfirlit yfir stífkrampa

Modelling the 20th and 21st century evolution of Hoffellsjökull glacier, SE-Vatnajökull, Iceland

The Little Ice Age maximum extent of glaciers in Iceland was reached about 1890 AD and most glaciers in the country have retreated during the 20th century. A model for the surface mass balance and the flow of glaciers is used to reconstruct the 20th century retreat history of Hoffellsjökull, a south-flowing outlet glacier of the ice cap Vatnajökull, which is located close to the southeastern coast of Iceland. The bedrock topography was surveyed with radio-echo soundings in 2001. A wealth of data are available to force and constrain the model, e.g. surface elevation maps from ~1890, 1936, 1946, 1989, 2001, 2008 and 2010, mass balance observations conducted in 1936–1938 and after 2001, energy balance measurements after 2001, and glacier surface velocity derived by kinematic and differential GPS surveys and correlation of SPOT5 images. The approximately 20% volume loss of this glacier in the period 1895–2010 is realistically simulated with the model. After calibration of the model with past observations, it is used to simulate the future response of the glacier during the 21st century. The mass balance model was forced with an ensemble of temperature and precipitation scenarios derived from 10 global and 3 regional climate model simulations using the A1B emission scenario. If the average climate of 2000–2009 is maintained into the future, the volume of the glacier is projected to be reduced by 30% with respect to the present at the end of this century. If the climate warms, as suggested by most of the climate change scenarios, the model projects this glacier to almost disappear by the end of the 21st century. Runoff from the glacier is predicted to increase for the next 30–40 yr and decrease after that as a consequence of the diminishing ice-covered area

Elevation Change, Mass Balance, Dynamics, and Surging of Langjökull, Iceland from 1997 to 2007

Glaciers and ice caps around the world are changing quickly, with surge-type behaviour superimposed upon climatic forcing. Here, we study Iceland’s second largest ice cap, Langjökull, which has both surge- and non-surge-type outlets. By differencing elevation change with surface mass balance, we estimate the contribution of ice dynamics to elevation change. We use DEMs, in situ stake measurements, regional reanalyses, and a mass balance model to calculate the vertical ice velocity. Thus, we not only compare the geodetic, modelled, and glaciological mass balances, but also map spatial variations in glacier dynamics. Maps of emergence and submergence velocity successfully highlight the 1998 surge and subsequent quiescence of one of Langjökull’s outlets by visualizing both source and sink areas. In addition to observing the extent of traditional surge behaviour (i.e., mass transfer from the accumulation area to the ablation area followed by recharge of the source area), we see peripheral areas where the surge impinged upon an adjacent ridge and subsequently retreated. While mass balances are largely in good agreement, discrepancies between modelled and geodetic mass balance may be explained by inaccurate estimates of precipitation, saturated adiabatic lapse rate, or degree day factors. Nevertheless, the study was ultimately able to investigate dynamic surge behaviour in the absence of in situ measurements during the surge.In situ mass balance survey is a joint effort of the Glaciology Group, Institute of Earth Sciences, University of Iceland and the National Power Company (Landsvirkjun). We thank Philippe Crochet and Tómas Jóhannesson from the Icelandic Meteorological Office for providing the gridded climate data and for useful discussions about the climatology of Langjökull. The 2007 lidar data were collected by the UK Natural Environment Research Council Airborne Research and Survey Facility (Grant IPY 07-08). Additional funding was provided by the United States National Science Foundation (Grant No. DGE-1038596), St Catharine’s, St John’s and Trinity Colleges and the University of Cambridge B.B. Roberts and Scandinavian Studies Funds. We thank Cameron Rye for initial help coding the mass balance model.This is the author accepted manuscript. The final version is available from Cambridge University Press via https://doi.org/10.1017/jog.2016.5

Elevation change, mass balance, dynamics and surging of Langjökull, Iceland from 1997 to 2007

ABSTRACTGlaciers and ice caps around the world are changing quickly, with surge-type behaviour superimposed upon climatic forcing. Here, we study Iceland's second largest ice cap, Langjökull, which has both surge- and non-surge-type outlets. By differencing elevation change with surface mass balance, we estimate the contribution of ice dynamics to elevation change. We use DEMs, in situ stake measurements, regional reanalyses and a mass-balance model to calculate the vertical ice velocity. Thus, we not only compare the geodetic, modelled and glaciological mass balances, but also map spatial variations in glacier dynamics. Maps of emergence and submergence velocity successfully highlight the 1998 surge and subsequent quiescence of one of Langjökull's outlets by visualizing both source and sink areas. In addition to observing the extent of traditional surge behaviour (i.e. mass transfer from the accumulation area to the ablation area followed by recharge of the source area), we see peripheral areas where the surge impinged upon an adjacent ridge and subsequently retreated. While mass balances are largely in good agreement, discrepancies between modelled and geodetic mass balance may be explained by inaccurate estimates of precipitation, saturated adiabatic lapse rate or degree-day factors. Nevertheless, the study was ultimately able to investigate dynamic surge behaviour in the absence of in situ measurements during the surge.In situ mass balance survey is a joint effort of the Glaciology Group, Institute of Earth Sciences, University of Iceland and the National Power Company (Landsvirkjun). We thank Philippe Crochet and Tómas Jóhannesson from the Icelandic Meteorological Office for providing the gridded climate data and for useful discussions about the climatology of Langjökull. The 2007 lidar data were collected by the UK Natural Environment Research Council Airborne Research and Survey Facility (Grant IPY 07-08). Additional funding was provided by the United States National Science Foundation (Grant No. DGE-1038596), St Catharine’s, St John’s and Trinity Colleges and the University of Cambridge B.B. Roberts and Scandinavian Studies Funds. We thank Cameron Rye for initial help coding the mass balance model.This is the author accepted manuscript. The final version is available from Cambridge University Press via https://doi.org/10.1017/jog.2016.5

Injection-induced surface deformation and seismicity at the Hellisheidi geothermal field, Iceland

Induced seismicity is often associated with fluid injection but only rarely linked to surface deformation. At the Hellisheidi geothermal power plant in south-west Iceland we observe up to 2 cm of surface displacements during 2011–2012, indicating expansion of the crust. The displacements occurred at the same time as a strong increase in seismicity was detected and coincide with the initial phase of geothermal wastewater reinjection at Hellisheidi. Reinjection started on September 1, 2011 with a flow rate of around 500 kg/s. Micro-seismicity increased immediately in the area north of the injection sites, with the largest seismic events in the sequence being two M4 earthquakes on October 15, 2011. Semi-continuous GPS sites installed on October 15 and 17, and on November 2, 2011 reveal a transient signal which indicates that most of the deformation occurred in the first months after the start of the injection. The surface deformation is evident in ascending TerraSAR-X data covering June 2011 to May 2012 as well. We use an inverse modeling approach and simulate both the InSAR and GPS data to find the most plausible cause of the deformation signal, investigating how surface deformation, seismicity and fluid injection may be connected to each other. We argue that fluid injection caused an increase in pore pressure which resulted in increased seismicity and fault slip. Both pore pressure increase and fault slip contribute to the surface deformation

Using dissolved H₂O in rhyolitic glasses to estimate palaeo-ice thickness during a subglacial eruption at Bláhnúkur(Torfajökull, Iceland)

The last decade has seen the refinement of a technique for reconstructing palaeo-ice thicknesses based on using the retained H2O and CO2 content in glassy eruptive deposits to infer quenching pressures and therefore ice thicknesses. The method is here applied to Bláhnúkur, a subglacially erupted rhyolitic edifice in Iceland. A decrease in water content from ~0.7 wt.% at the base to ~0.3 wt.% at the top of the edifice suggests that the ice was 400 m thick at the time of the eruption. As Bláhnúkur rises 350 m above the surrounding terrain, this implies that the eruption occurred entirely within ice, which corroborates evidence obtained from earlier lithofacies studies. This paper presents the largest data set (40 samples) so far obtained for the retained volatile contents of deposits from a subglacial eruption. An important consequence is that it enables subtle but significant variations in water content to become evident. In particular, there are anomalous samples which are either water-rich (up to 1 wt.%) or water-poor (~0.2 wt.%), with the former being interpreted as forming intrusively within hyaloclastite and the latter representing batches of magma that were volatile-poor prior to eruption. The large data set also provides further insights into the strengths and weaknesses of using volatiles to infer palaeo-ice thicknesses and highlights many of the uncertainties involved. By using examples from Bláhnúkur, the quantitative use of this technique is evaluated. However, the relative pressure conditions which have shed light on Bláhnúkur’s eruption mechanisms and syn-eruptive glacier response show that, despite uncertainties in absolute values, the volatile approach can provide useful insight into the mechanisms of subglacial rhyolitic eruptions, which have never been observed