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INTRODUCTION: Pulmonary complications may occur in the post-operative period and are a significant cause of morbidity and mortality in patients undergoing anesthesia and surgery. Complication rates vary according to different procedures and different types of anesthesia and may be affected by the patient condition. The purpose of this study was to examine pulmonary complications following percutaneous nephrolithotomy (PCNL) and to search for associations between the pre- and intra-operative factors and the risk of post-operative pulmonary complications (PPC). PATIENTS AND METHODS: This was a prospective observational study of 100 consecutive adult patients who underwent PCNL surgery. We collected data of the patient, surgery and anesthesia and analyzed it to find correlations with PPC. RESULTS: Eight (8%) patients had PPC following PCNL, 7 patients had pneumothorax and 1 had atelectasis and pleural effusion. The latter patient died at post-operative day 24 due to respiratory failure. It was found that patients who had PCNL on the right kidney were at lower risk for PPC. In addition it was found that younger patients had a higher incidence of PPC. CONCLUSIONS: Based on this study the most common type of post-operative complication following PCNL is pulmonary, with pneumothorax being the main complication. PPC may result in patient mortality. The side of the operation and the patient's age might affect the risk of PPC.
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PNPase is a major exoribonuclease that plays an important role in the degradation, processing, and polyadenylation of RNA in prokaryotes and organelles. This phosphorolytic processive enzyme uses inorganic phosphate and nucleotide diphosphate for degradation and polymerization activities, respectively. Its structure and activities are similar to the archaeal exosome complex. The human PNPase was recently localized to the intermembrane space (IMS) of the mitochondria, and is, therefore, most likely not directly involved in RNA metabolism, unlike in bacteria and other organelles. In this work, the degradation, polymerization, and RNA-binding properties of the human PNPase were analyzed and compared to its bacterial and organellar counterparts. Phosphorolytic activity was displayed at lower optimum concentrations of inorganic phosphate. Also, the RNA-binding properties to ribohomopolymers varied significantly from those of its bacterial and organellar enzymes. The purified enzyme did not preferentially bind RNA harboring a poly(A) tail at the 3' end, compared to a molecule lacking this tail. Several site-directed mutations at conserved amino acid positions either eliminated or modified degradation/polymerization activity in different manners than observed for the Escherichia coli PNPase and the archaeal and human exosomes. In light of these results, a possible function of the human PNPase in the mitochondrial IMS is discussed.
