ABSTRACT
UNLABELLED: Management of medical cardiac arrest is challenging. The internationally agreed approach is highly protocolised with therapy and diagnosis occurring in parallel. Early identification of the precipitating cause increases the likelihood of favourable outcome. Echocardiography provides an invaluable diagnostic tool in this context. Acquisition of echo images can be challenging in cardiac arrest and should occur in a way that minimises disruption to cardiopulmonary resuscitation (CPR). In this article, the reversible causes of cardiac arrest are reviewed with associated echocardiography findings. CASE: A 71-year-old patient underwent right upper lobectomy for lung adenocarcinoma. On the 2nd post-operative day, he developed respiratory failure with rising oxygen requirement and right middle and lower lobe collapse and consolidation on chest X-ray. He was commenced on high-flow oxygen therapy and antibiotics. His condition continued to deteriorate and on the 3rd post-operative day he was intubated and mechanically ventilated. Six hours after intubation, he became suddenly hypotensive with a blood pressure of 50 systolic and then lost cardiac output. ECG monitoring showed pulseless electrical activity. CPR was commenced and return of circulation occurred after injection of 1 mg of adrenaline. Focused echocardiography was performed, which demonstrated signs of massive pulmonary embolism. Thrombolytic therapy with tissue plasminogen activator was given and his condition stabilised.
ABSTRACT
BACKGROUND AND PURPOSE: The Zweymüller-Plus system (SL-Plus stem, Bicon-Plus threaded cup) for primary total hip arthroplasty (THA) was introduced in 1993, as a successor of the Alloclassic THA with a few modifications in the conical stem shape and a new biconical threaded cup with a spherical shape. The medium-term performance of this system is not well established. To better understand the potential impact these design changes have had on (1) survivorship, (2) implant stability and (3) periprosthetic osteolysis, we studied patients who underwent THA using the SL-Plus stem and Bicon-Plus. METHODS: We retrospectively reviewed the cases of 148 patients (153 hips) who underwent Zweymüller-Plus primary THA after an average of 11 years. RESULTS: With revision for aseptic failure of biological fixation as the endpoint, survivorship was 98% for the stem and 100% for the cup. Focal osteolysis was observed in 6.6% of cups and 29% of stems. Four hips (2.6%) were revised because of aseptic failure of the biologic fixation and three hips (1.95%) for deep infection. As much as 146 stems and 149 cups were evaluated to be stable. CONCLUSION: Zweymüller-Plus THA resulted in high survivorship and durability at 11 years, although the rate of osteolysis around the stem indicated polyethylene wear.
Subject(s)
Arthroplasty, Replacement, Hip , Adult , Aged , Aged, 80 and over , Female , Hip Prosthesis , Humans , Male , Middle Aged , Osteolysis , Prosthesis Design , Retrospective StudiesABSTRACT
Delayed complications following lumbar spine fusion may occur amongst which is adjacent segment degeneration (ASD). Although interspinous implants have been successfully used in spinal stenosis to authors' knowledge such implants have not been previously used to reduce ASD in instrumented lumbar fusion. This prospective controlled study was designed to investigate if the implantation of an interspinous implant cephalad to short lumbar and lumbosacral instrumented fusion could eliminate the incidence of ASD and subsequently the related re-operation rate. Groups W and C enrolled initially each 25 consecutive selected patients. Group W included patients, who received the Wallis interspinous implant in the unfused vertebral segment cephalad to instrumentation and the group C selected age-, diagnosis-, level-, and instrumentation-matched to W group patients without interspinous implant (controls). The inclusion criterion for Wallis implantation was UCLA arthritic grade
Subject(s)
Intervertebral Disc Displacement/prevention & control , Lumbar Vertebrae/surgery , Prostheses and Implants , Spinal Fusion/instrumentation , Spinal Stenosis/surgery , Spondylolisthesis/surgery , Adult , Aged , Decompression, Surgical/instrumentation , Decompression, Surgical/methods , Disability Evaluation , Female , Humans , Internal Fixators , Intervertebral Disc/pathology , Intervertebral Disc/physiopathology , Intervertebral Disc Displacement/etiology , Intervertebral Disc Displacement/physiopathology , Lumbar Vertebrae/diagnostic imaging , Lumbar Vertebrae/pathology , Magnetic Resonance Imaging , Male , Middle Aged , Postoperative Complications/etiology , Postoperative Complications/physiopathology , Postoperative Complications/prevention & control , Prospective Studies , Spinal Fusion/methods , Spinal Stenosis/diagnostic imaging , Spinal Stenosis/pathology , Spondylolisthesis/diagnostic imaging , Spondylolisthesis/pathology , Tomography, X-Ray ComputedABSTRACT
Variable viruses, such as human immunodeficiency virus (HIV) and hepatitis C virus (HCV), persist despite host immune responses directed against them. Numerous lines of evidence have suggested that antiviral CD8+ T-cell responses are key among these immune responses, but these vary widely in their ability to contain virus. We propose that only a proportion of responses may exert significant antiviral pressure ('driver' responses), leading to control over viral replication (protection) and/or, ultimately, selection of escape mutants. Another set of responses may exert only weak pressure on the virus ('passenger' responses): these neither protect nor select. To examine this we have analysed (using established databases of HIV and HCV sequences and cytotoxic T-lymphocyte (CTL) epitopes, and published experimental datasets) two important features--predicted binding of the epitope to major histocompatibility complex molecule and observed variability of the epitope--that might distinguish such responses. We find that a high predicted binding estimate could only explain a limited set of 'driver' responses associated with protection or selection. There is statistical evidence that readily defined (and non-protective) CTL responses target regions associated with lower levels of viral variability. Taken together, this suggests that a large number of well-documented responses may represent 'passengers' and we propose a mechanism that might explain their presence.