Severe group A streptococcal infection and streptococcal toxic shock syndrome

PURPOSE

To review the literature on group A streptococcal toxic shock syndrome, (STSS).

DATA SOURCE

Medline and EMBASE searches were conducted using the key words group A streptococcal toxic shock syndrome, alone and in combination with anesthesia; and septic shock, combined with anesthesia. Medline was also searched using key words intravenous immunoglobulin, (IVIG) and group A streptococcus, (GAS); and group A streptococcus and antibiotic therapy. Other references were included in this review if they addressed the history, microbiology, pathophysiology, incidence, mortality, presentation and management of invasive GAS infections. Relevant references from the papers reviewed were also considered. Articles on the foregoing topics were included regardless of study design. Non-English language studies were excluded. Literature on the efficacy of IVIG and optimal antibiotic therapy was specifically searched.

PRINCIPAL FINDINGS

Reports of invasive GAS infections have recently increased. Invasive GAS infection is associated with a toxic shock syndrome, (STSS), in 8-14% of cases. The STSS characteristically results in shock and multi-organ failure soon after the onset of symptoms, and is associated with a mortality of 33-81%. Many of these patients will require extensive soft tissue debridement or amputation in the operating room, on an emergency basis. The extent of tissue debridement required is often underestimated before skin incision.

CONCLUSIONS

Management of STSS requires volume resuscitation, vasopressor/inotrope infusion, antibiotic therapy and supportive care in an intensive care unit, usually including mechanical ventilation. Intravenous immunoglobulin infusion has been recommended. Further studies are needed to define the role of IVIG in STSS management and to determine optimal anesthetic management of patients with septic shock.

A comparison of thoracic and lumbar epidural techniques for post-thoracoabdominal esophagectomy analgesia

PURPOSE

To compare thoracic epidural analgesia (TEA) using a bupivacaine/fentanyl mixture and lumbar epidural analgesia (LEA) with morphine, in respect to the time to extubation and the quality of post-operative analgesia, in patients having thoracoabdominal esophagectomy.

METHODS

Twenty two patients scheduled for elective thoracoabdominal esophagectomy were randomized to TEA or LEA. Postoperatively, the TEA group received Patient Controlled Epidural Analgesia (PCEA) with bupivacaine 0.125% and 5 microg x ml(BI) fentanyl, and the LEA group received PCEA with 0.2 microg x ml(BI) morphine. A blinded observer assessed criteria for tracheal extubation and the time of tracheal extubation was recorded. Early extubation was defined as tracheal extubation within four hours postoperatively. Visual analogue pain scores at rest (Static Visual Analogue Pain Scores, SVAPS) and with movement (Dynamic Visual Analogue Pain Scores, DVAPS) were recorded at 1, 6, 12, 18 and 24 hr post-extubation. Failure of the epidural protocol (FEP) was defined as a request for additional analgesia.

RESULTS

Tracheal extubation was achieved in 70% of the LEA and 100% of the TEA at four hours postoperatively (P=NS). However, the TEA group achieved earlier extubation times when assessed with log rank testing (P = 0.01). By six hours post-extubation FEP had occurred in 50% of the LEA group but in none of the TEA group (P = 0.01). Mean SVAPS and DVAPS were lower in the TEA than in the LEA group at all measured times (P < 0.01).

CONCLUSION

This study has demonstrated superior pain control in patients undergoing thoraco-abdominal esophagectomy treated with TEA than with LEA, particularly for pain with movement. Tracheal extubation occurred earlier in the TEA group, but this difference was not significant at four hours postoperatively.

Gene sequence encoding early enzymes of arginine synthesis within a cluster in Bacillus subtilis, as revealed by cloning in Escherichia coli

From a partial Sau3A gene library of Bacillus subtilis chromosomal DNA in the expression plasmid pRK9, four hybrid plasmids were isolated carrying overlapping segments of the argA-argF-cpa cluster. The complementation patterns within Escherichia coli arginine auxotrophs of these hybrids and deletion derivatives provided the gene order argC-argA-argE-argB-argD-cpa-argF.

The pharmacokinetics and pharmacodynamics of minaxolone

Plasma concentrations of minaxolone were measured in 15 female patients during and for up to 3 hours after a minaxolone and nitrous oxide anesthetic. Nine patients received a single dose and six patients two or three doses of minaxolone. Plasma minaxolone decay can be described by two-compartment kinetics. Distribution is rapid, with a mean half-life of 2.1 minutes, and the elimination half-life is short (47 minutes). Plasma clearance is high (1.55 l./min). Plasma levels of minaxolone at recovery were similar in patients receiving both single and multiple doses, suggesting a valid relationship between plasma level and effect. It is suggested that minaxolone may be a suitable agent for administration by continuous infusion.

The efficacy of bupivacaine 0.75 per cent as an epidural test dose

Two cases are presented in which a test dose of bupivacaine 0.75 per cent was injected before institution of an epidural block, as a safeguard against inadvertent intrathecal injection. In each case there was immediate evidence of motor and sensory blockade, which gave warning that the epidural catheter was positioned in the subarachnoid space. The experience of these two cases indicates that bupivacaine 0.75 per cent would be appropriate for use as a test dose in epidural anaesthesia.

An early clinical assessment of the steroid anaesthetic Minaxolone

Minaxolone, a new water-soluble steroid anaesthetic, was studied in combination with nitrous oxide in 30 healthy female patients. The objective of the study was to assess induction dosage, clinical efficacy, recovery characteristics, and frequency of side effects. It proved to be an effective anaesthetic causing only minimal cardiovascular and respiratory depression. Those side effects which occurred during operation were felt to be due in part to light anaesthesia and lack of analgeia. Excitatory movements and hypertonus occurred in seven patients during operation and in ten patients in the early recovery phase. Late recovery was impressive, both in quality and lack of side effects, and all patients were considered fit for discharge from hospital within four hours of the operation. Minaxolone appears to be a promising new anaesthetic worthy of further study.

Further characterization of a lipopolysaccharide from Coxiella burneti

The lipopolysaccharide previously isolated from the rickettsial agent of Q fever, Coxiella burneti, phase I, has been further characterized. The sugar residues ribose, mannose, gluclose, D-glycero-D-mannoheptose, and L-glycerto-D-mannoheptose are present. Two sugars remain unidentified, one of which is a minor and the other a major constituent. Isomyristic, palmitic, and beta-hydroxymyristic acids are the major fatty acid residues of the 15 identified. The nature and content of other lipopolysaccharide constituents are presented.

Biosynthesis and cytokinin activity of 8-hydroxy and 2,8-dihydroxy derivatives of zeatin and N-6(increment-2-isopentenyl)adenine

8-Hydroxy and 2,8-dihydroxy derivatives of the cytokinins, 6-(4-hydroxy-3-methyl-trans-2-butenylamino)purine and N-6-(increment -2-isopentenyl)adenine, have been biosynthesized by xanthine oxidase oxidation. 8-Hydroxy derivatives have been shown to be the major intermdeiates. These compounds were tested for cytokinin activity in the tobacco bioassay. The results suggest that substitution of the 8 position with a hydroxyl group causes less decrease of cytokinin activity than substitution of both the 2 and 8 positions with hydroxyl groups.

The formation, isolation, and biological activity of a cytokinin 7-glucoside

The cytokinin, 6-benzylaminopurine, is converted to its 7-glucoside in intact seedlings, organ slices, and tissue cultures from several plants. The ribonucleoside and 5'-ribonucleotide appear transiently, and the general metabolic sequence seems to be nearly identical in the four plant species thus far studied. The glucoside persists for long periods in plant tissues, while all other forms of the cytokinin are rapidly metabolized and disappear within a few hours. A procedure for the isolation in pure form of the glucoside is described.