Hemolytic mutants of group A Streptococcus pyogenes.

Hemolytic mutants of Lancefield strain SS-95 and ATCC 19615 Streptococcus pyogenes were produced by treatment with N-methyl-N'-nitro-N-nitrosoguanidine. These mutants contained the same levels of streptolysin O, nicotinamide adenine dinucleotidase, deoxyribonuclease, and hyaluronidase. The mutants were deficient in streptolysin S, as was the naturally occurring nonhemolytic Lowry strain.

An unusual complication of lumbosacral plexus block: a case report.

Lumbosacral plexus block is a valuable anesthetic technic in the hands of an experineced anesthesiologist. However, as illustrated by this case report, anesthetic dosage must be selected with great care, and patients unable to describe paresthesias should be excluded from use of this procedure.

Development of two indices of postoperative morbidity.

Two indices of postoperative morbidity, Nursing Assessment Index and Observed Treatment Index, are described and evaluated in this study of 4,182 consecutive anesthetics. The use of these indices in studies of the quality and effectiveness of surgical and anesthetic care should increase the economy and precision with which the causes of unsatisfactory outcome are identified. Specific illustrations of the relationship of the preanesthetic status of patients to their postoperative morbidity as measured by these indices and mortality rates are given.

Pericardiocentesis: insertion of a pericardial catheter.

Pericardiocentesis is a lifesaving procedure in cardiac tamponade but is associated with significant and often life threatening complications. A patient is described in whom a catheter was inserted into the pericardium. This provided for prolonged pericardial drainage of purulent fluid and has the potential for decreasing the risk of this procedure.

Hypoventilation in a newborn following administration of succinylcholine to the mother: a case report.

Analysis of maternal and neonatal blood samples for cholinesterase-activity determination revealed a case of hypoventilation in the newborn to be apparently secondary to succinylcholine administration to the mother during obstetric anesthesia.