Toxic metabolic encephalopathy after parathyroidectomy with methylene blue localization.

OBJECTIVE: To determine the correlation between methylene blue use and toxic metabolic encephalopathy in patients undergoing surgery for primary hyperparathyroidism. STUDY DESIGN AND SETTING: A retrospective study of 193 patients was performed to collect demographic, perioperative, and postoperative data. Patients were divided into two groups: Group A (postoperative neurological sequelae) and Group B (no neurological sequelae). All data points were compared between the groups. RESULTS: Twelve of 193 patients were placed in Group A; 181 patients were placed in Group B. Ten patients in Group A were female, and 10 patients were older than 60 years. Of the patients in Group A, 100% were taking a serotonin reuptake inhibitor (SRI). In Group B, 8.8% of patients were taking an SRI. CONCLUSION: All the patients who experienced transient neurological events were taking an SRI. A correlation can be made between methylene blue infusion and SRI usage. SIGNIFICANCE: Patients taking SRIs may represent a high-risk group for postoperative neurological events when methylene blue is utilized.

Comparison of incidence of invasive Streptococcus pneumoniae disease among children before and after introduction of conjugated pneumococcal vaccine.

OBJECTIVES: The objective was to determine whether there has been a significant decrease in the incidence of invasive Streptococcus pneumoniae disease in the Louisville, KY, area since heptavalent pneumococcal conjugate vaccine was introduced in the winter of 1999-2000. A secondary objective was to collect demographic data regarding invasive S. pneumoniae disease in the Louisville, KY, area during the 1997-2002 period. METHODS: Data on cases of invasive S. pneumoniae disease (defined by a positive culture for S. pneumoniae from the blood, pleural fluid or cerebrospinal fluid) were collected from the microbiology laboratories and medical records departments of all hospitals that treat children in the Louisville area, for 1997-2002. Trends in case rates for all cases of invasive S. pneumoniae disease from 1999 to 2002 were observed, and demographic and other factors regarding this illness were recorded for each patient. RESULTS: The trend for rates of invasive pneumococcal disease showed a significant decrease during the study period for all ages combined (P < 0.001), for children younger than 2 years of age (P = 0.002) and for children 2 to 5 years of age (P = 0.002). The mean age for children was 2.22 years, with a male/female ratio of 1.8:1. The most common final diagnoses for the patients were bacteremia without focus, pneumonia and meningitis. Forty-eight percent of the organisms were resistant to penicillin. There was a significantly higher rate of resistance to penicillin among S. pneumoniae strains that caused cerebrospinal fluid infection than among strains that caused non-cerebrospinal fluid infection (P < 0.001). The case fatality rate was 2.6%. CONCLUSION: Case rates for invasive S. pneumoniae disease among children decreased significantly in the 2-year period after introduction of the heptavalent S. pneumonia protein conjugate vaccine into this community.

Operating room sound level hazards for patients and physicians.

HYPOTHESIS: Exposure to certain new surgical instruments and operating room devices during procedures could cause hearing damage to patients and personnel. BACKGROUND: Surgical instruments and related equipment generate significant sound levels during routine usage. Both patients and physicians are exposed to these levels during the operative cases, many of which can last for hours. The noise loads during cases are cumulative. Occupational Safety and Health Administration (OSHA) and National Institute for Occupational Safety and Health (NIOSH) standards are inconsistent in their appraisals of potential damage. Implications of the newer power instruments are not widely recognized. METHODS: Bruel and Kjaer sound meter spectral recordings for 20 major instruments from 5 surgical specialties were obtained at the ear levels for the patient and the surgeon between 32 and 20 kHz. RESULTS: Routinely used instruments generated sound levels as high as 131 dB. Patient and operator exposures differed. There were unilateral dominant exposures. Many instruments had levels that became hazardous well within the length of an average surgical procedure. The OSHA and NIOSH systems gave contradicting results when applied to individual instruments and types of cases. Background noise, especially in its intermittent form, was also of significant nature. Some patients and personnel have additional predisposing physiologic factors. CONCLUSION: Instrument noise levels for average length surgical cases may exceed OSHA and NIOSH recommendations for hearing safety. Specialties such as Otolaryngology, Orthopedics, and Neurosurgery use instruments that regularly exceed limits. General operating room noise also contributes to overall personnel exposures. Innovative countermeasures are suggested.