Search

Background : The incidence of sedation-related adverse events, inclusive of both adults and children, administered by multiple specialty providers from different countries and venues, using standardized definitions, has never been reported on an international level. We are reporting the outcome data of the adverse event sedation reporting tool as an important step toward a more complete risk assessment of sedation-related morbidity, mortality, and etiology. The analysis of the AE sedation reporting data include descriptive measures to evaluate the characteristics of the provider, the patient, sedations performed, adverse events, interventions, and outcomes. The primary outcome was the rate and nature of adverse events. Between 12/14/2010 and 12/11/2018 there were 7952 sedations, from an estimated total of 164,114 sedations administered, of which 622 were reported as adverse events. The mean age of the entire patient population is 33.0 years (0.02-98.7). The providers represented 39 countries across six continents. Oxygen desaturation (75%-90%) for <60 s is the most prevalent adverse event with a rate of 7.8 per 10,000, followed by airway obstruction at a rate of 5.42 per 10,000. Apnea occurred at a rate of 4.75 per 10,000. Significant predictors of adverse events are ≥ ASA score III ( p = 0.0003), procedure time (6:00 pm-12:00 am: p < 0.0001, 12:00-6:00 am: p = 0.0003), and non-hospital location ( p < 0.0001). The AE sedation reporting tool has demonstrated that the majority of adverse events in children and adults who receive procedural sedation from multi-specialists internationally required minor interventions and had outcomes of minor risk.

Mutants of the plasma membrane Ca2+ pump (PMCA), in which amino acids in transmembrane domains (TM) 4, 6, and 8 had been replaced, have been expressed in COS-7 cells. They were analyzed functionally by measuring the uptake of Ca2+ in microsomal preparations and by following the formation of the phosphorylated intermediate from ATP and from phosphate. The mutated residues corresponded to amino acids whose mutation in the sarcoplasmic reticulum pump (SERCA) caused loss of Ca2+ transport by the pump protein: however, only four of the six SERCA residues were conserved in the PMCA pump. Mutation of Glu423 (TM4), Asn879 or Asp883 (TM6), or Gln97l (TM8) suppressed Ca2+ transport by the pump and its ability to form the phosphorylated intermediate starting from ATP. By contrast, the ability of these mutants to form the intermediate starting from phosphate was not impaired. In two mutants (Glu423 and Asp883) it was even enhanced. Two conserved Pro residues of TM4 were also mutated, leading to the loss of the ability of the pump to form the Ca2+- and ATP-dependent phosphorylated intermediate. Unexpectedly, two of the mutations (Asn879 and Gln971) led to the mistargeting of the mutated proteins, i.e., to their retention in the endoplasmic reticulum.

The plasma membrane Ca(2+)-ATPase isoform 4b (PMCA4CI) with truncations in the cytoplasmically exposed COOH-terminal tail was expressed in COS and HeLa cells and in Sf9 cells using the baculovirus system. The truncated protein terminating with the acidic sequence Glu1067-Arg1087 was retained within the endoplasmic reticulum (ER), whereas mutants lacking this sequence or having it at a distance from the COOH terminus were delivered to the plasma membrane. Although the truncated protein retained in the endoplasmic reticulum was still able to form a Ca(2+)-dependent phosphoenzyme, it underwent partial degradation. Substitution of glutamic and aspartic residue(s) in the acidic region promoted rescue of the protein to the plasma membrane. The results suggest that the sequence Glu1067-Arg1087 encodes a masked signal for ER retention and for the degradation of the protein. However, its presence at the COOH terminus was not sufficient to induce ER-retention and degradation; when the sequence was attached to the full-length PMCA protein, normal plasma delivery was observed. Evidently, ER retention and degradation required the presence of the sequence in its specific location within the PMCA structure. The degradation of the protein retained in the endoplasmic reticulum occurred through the proteolytic attack at cytoplasmically exposed residues (amino acid sequence 720-750) by a cytoplasmic PEST sequence-related protease different from calpain.