Desulfurization of the thiocarbonyl ligand in square pyramidal [Ru(CS)Cl2(PCy3)2] (1-S) via sulfur atom abstraction using [Mo(H)(eta2-Me2CNAr)(N[i-Pr]Ar)2] forms [Ru(C)Cl2(PCy3)2] (1) cleanly over several hours in benzene; isolated yield is 55%. Complex 1 is also formed in 87% isolated yield upon reaction of [Ru(CHR)(PCy3)2Cl2] (R = p-C6H4Me, 2; Ph, 3) with vinyl acetate in dichloromethane. Complex 1-S is re-formed quantitatively from 1 upon treatment with elemental sulfur in CH2Cl2, but is prepared most conveniently by treatment of crude [Ru(CS)Cl2(PPh3)2(OH2)] with excess PCy3 in toluene. Nearly quantitative conversion of 1 to [Ru(CO)Cl2(PCy3)2] (1-O) occurs upon addition of dimethyldioxirane solution in acetone to 1 dissolved in CH2Cl2 at ca. -90 degrees C.

Purpose Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes syndrome (MELAS) is a rare inherited mitochondrial disorder associated with severe multiorgan pathology and stress-induced episodes of metabolic decompensation and lactic acidosis. The purpose of this case series is to review the medical records of patients with MELAS who underwent anesthetic care at the Mayo Clinic to observe their perioperative responses to anesthesia and to assess outcomes. Principal findings From September 1997 to October 2010, nine patients with MELAS were identified who underwent 20 general anesthetics, 12 prior to MELAS diagnosis. Debilitating neurologic symptoms involved eight patients, and three patients had substantial cardiac comorbidities. The patients tolerated commonly used anesthetics and muscle relaxants, including succinylcholine. Lactated Ringer's solution was used frequently. One patient was noted to have elevated postoperative serum lactate, but his serum lactate was chronically elevated. Metabolic acidosis was not observed in any patient. Hyponatremia and hyperkalemia, sometimes profound, were observed in seven patients, but these abnormalities also occurred at times remote from surgery. Two patients developed renal dysfunction following cardiac surgery and abdominal surgery for severe sepsis. Conclusion The MELAS patients developed episodes of hyponatremia and hyperkalemia of variable severity unrelated to the timing of surgery, suggesting these patients are prone to major electrolyte disturbances. Given the propensity to develop acid-base disturbances and lactacidemia, it is prudent to review and normalize electrolyte abnormalities and to adjust the anesthetic plan accordingly. Fortunately, the limited data suggest that patients with MELAS tolerate commonly used anesthetic drugs well. RésuméObjectif L'ence´phalomyopathie mitochondriale avec acidose lactique et e´pisodes ressemblant a`des accidents vasculaires ce´re´braux (MELAS) est un trouble mitochondrial he´re´ditaire rare associe´a`une pathologie grave touchant plusieurs organes et des e´pisodes de de´compensation me´tabolique et d'acidose lactique provoque´s par le stress. L'objectif de cette se´rie de cas est d'examiner les dossiers me´dicaux de patients atteints de MELAS et ayant reçu des soins anesthe´siques a`la Clinique Mayo afin d'observer leurs re´ponses pe´riope´ratoires a`l'anesthe´sie et d'e´valuer leurs devenirs. Constatations principales Pour la pe´riode allant de septembre 1997 a`octobre 2010, nous avons identifie´neuf patients atteints de MELAS ayant subi 20 anesthe´sies ge´ne´rales, dont 12 avant que le diagnostic de MELAS n'ait e´te´e´tabli. Les symptômes neurologiques de´bilitants ont touche´huit patients, et trois patients ont manifeste´des

Contrary to previous case reports, we found that patients with HD have normal responses to general anesthesia. However, the anesthesiologist should be aware of interactions between anesthetics and psychiatric medications frequently used by these patients. Measures should also be taken to minimize the risk of pulmonary aspiration because bulbar dysfunction may be a manifestation of this disease.

Osteogenesis imperfecta patients undergoing non-cardiac surgery experienced mild intraoperative hyperpyrexia which was not different from those without osteogenesis imperfecta.