Biomedical subjects

C H Heath

Publications and source records attributed to C H Heath.

5 recordsLinked to original sources

PubMed1996

Emerging resistance in Enterococcus spp.

Enterococcus spp. are becoming increasingly important nosocomial pathogens. They are intrinsically resistant to most antibiotics, and effective therapy depends primarily on the penicillins, vancomycin and the aminoglycosides. Under antibiotic selection pressure they have developed high level resistance to these agents, and the first vancomycin-resistant enterococcal infection in Australia was described recently. The vancomycin-resistance genes are of particular concern because of their potential to transfer to other gram-positive organisms. The prevention and control of resistant enterococci is a major challenge that is best met by a combination of active infection control measures and restriction of broad-spectrum antibiotic use.

Anti-Bacterial Agents↗

PubMed1996

Delay in appropriate therapy of Legionella pneumonia associated with increased mortality.

The prognostic significance of delayed therapy in Legionnaires' disease is poorly defined. Thirty-nine consecutive serologically confirmed cases of Legionnaires' disease were reviewed to examine whether an association exists between delayed therapy and prognosis. Clinical and laboratory factors predictive of mortality were also sought. Thirty-one cases (79%) were classified as having severe pneumonia at diagnosis. Thirty-six patients (92%) had community-acquired infection, and three patients (8%) had nosocomial disease. Ten patients died, resulting in a crude mortality rate of 26%. At the first assessment, variables noted for pneumonia associated with death were low diastolic blood pressure (p < 0.02), low serum albumin concentration (p < 0.04), and increased number of days from onset of pneumonia to hospitalisation (prodrome) (p < 0.02). However, multiple logistic regression analysis revealed that the prodrome was the only variable noted at diagnosis that achieved significance (p = 0.024). Mortality also correlated with both delay in the initiation of erythromycin therapy following admission (p < 0.001) and the total delay in starting erythromycin therapy (p < 0.001). It is therefore recommended that erythromycin be included early in the empiric therapy of severe community-acquired pneumonia.

Adult↗

PubMed1995

Cryptococcal disease of the CNS in immunocompetent hosts: influence of cryptococcal variety on clinical manifestations and outcome.

We performed a retrospective review of cases of cerebral cryptococcosis among patients admitted to 12 Australian teaching hospitals between 1985 and 1992. Of 118 cases identified, 35 occurred in immunocompetent hosts. When cases due to Cryptococcus neoformans variety neoformans were compared with those due to Cryptococcus neoformans variety gattii, we found that the latter tended to occur in healthy hosts whose residence or job was located in a rural area, and cerebral mass lesions and/or hydrocephalus and pulmonary mass lesions were more common. For a subgroup of patients with infection due to C. neoformans variety gattii, multiple enhancing lesions were observed on cerebral computed tomograms, and papilledema, high CSF and serum cryptococcal antigen titers, and a worse prognosis (despite prolonged amphotericin B therapy and intraventricular shunt insertion) were also noted. No significant difference in clinical course or outcome in terms of variety of C. neoformans was noted for patients with cryptococcal meningitis whose computed tomographic scans appeared normal on presentation.

AIDS-Related Opportunistic Infections↗

PubMedDate not supplied

Local anesthetic distribution in a spinal model: a possible mechanism of neurologic injury after continuous spinal anesthesia.

BACKGROUND AND OBJECTIVES: Cauda equina syndrome has been reported recently in patients receiving continuous spinal anesthesia using newly developed microcatheters (28 gauge). Failure of microcatheters to allow adequate mixing of local anesthetic was studied as a possible mechanism of the neurologic injury reported with these catheters. METHODS: A spinal canal model was developed and the distribution of hyperbaric lidocaine was measured after injection through catheters typically used for continuous spinal anesthesia (i.e., 20, 28, and 32 gauge). RESULTS: Lidocaine distribution was less uniform and lidocaine concentration and osmolarity in the dependent portions of the model were significantly higher after injection through microcatheters compared to the 20-gauge catheter. CONCLUSIONS: Dependent drug concentrations were greater than those reported in the literature, capable of producing permanent neurologic injury. Directing the catheter tip in the nondependent direction and injecting lidocaine rapidly or through catheters with multiple end holes improved mixing and decreased dependent drug concentration.

Anesthesia, Spinal↗

PubMedDate not supplied

Normal limits of knee angle in white children--genu varum and genu valgum.

Knee angle and intermalleolar (IM) or intercondylar (IC) distance were measured in 196 white children aged 6 months to 11 years to establish normal limits of tibiofemoral angle. Children were maximally bowlegged at age 6 months and progressed toward approximately neutral knee angles (0 degree) by age 18 months. Greatest mean knock knee of 8 degrees was observed at age 4 years, followed by a gradual decrease to a mean of < 6 degrees at 11 years. Normal children aged 2-11 years had knock knee up to 12 degrees and intermalleolar distance up to 8 cm; the existence of bowlegs after age 2 years was abnormal.

Age Factors↗