Search PubMed⌕ Search

Biomedical subjects

S M Gordon

Publications and source records attributed to S M Gordon.

At least 37 records · Page 2Linked to original sources
PubMed2000

Physiologically based pharmacokinetic modeling of the temperature-dependent dermal absorption of chloroform by humans following bath water exposures.

The kinetics of chloroform in the exhaled breath of human volunteers exposed skin-only via bath water (concentrations < 100 ppb) were analyzed using a physiologically based pharmacokinetic (PBPK) model. Significant increases in exhaled chloroform (and thus bioavailability) were observed as exposure temperatures were increased from 30 to 40 degrees C. The blood flows to the skin and effective skin permeability coefficients (Kp) were both varied to reflect the temperature-dependent changes in physiology and exhalation kinetics. At 40 degrees C, no differences were observed between males and females. Therefore, Kps were determined (approximately 0.06 cm/hr) at a skin blood flow rate of 18% of the cardiac output. At 30 and 35 degrees C, males exhaled more chloroform than females, resulting in lower effective Kps calculated for females. At these lower temperatures, the blood flow to the skin was also reduced. Total amounts of chloroform absorbed averaged 41.9 and 43.6 microg for males and 11.5 and 39.9 microg for females exposed at 35 and 40 degrees C, respectively. At 30 degrees C, only 2/5 males and 1/5 females had detectable concentrations of chloroform in their exhaled breath. For perspective, the total intake of chloroform would have ranged from 79-194 microg if the volunteers had consumed 2 liters of water orally at the concentrations used in this study. Thus, the relative contribution of dermal uptake of chloroform to the total body burdens associated with bathing for 30 min and drinking 2 liters of water (ignoring contributions from inhalation exposures) was predicted to range from 1 to 28%, depending on the temperature of the bath.

Adult↗
PubMed2000

Aspergillus valve endocarditis in patients without prior cardiac surgery.

Aspergillus native valve endocarditis in patients who have not had cardiac surgery is uncommon. We report 3 cases and review 58 other adult patients reported in the English-language literature. Sixty-seven percent of the patients had underlying immunosuppression. The clinical features were fever (74%), embolic episodes (69%), a new or changing heart murmur (41%), and sudden visual loss (13%). Patients with mural endocarditis were more often immunosuppressed, especially due to solid organ transplants, but had lower frequency of heart murmurs and embolic episodes. Echocardiography revealed a vegetation in 78% of all the cases in which it was performed. Examination and culture of biopsy material often helped to establish a diagnosis of Aspergillus infection. Twenty-five patients had an antemortem diagnosis. These patients received a mean cumulative amphotericin B dose of 27 mg/kg. Twenty percent (3/15) of patients who received combined surgical and medical therapy survived, compared to none of those who received medical therapy alone (p = 0.08). Patients who survived were not immunosuppressed. We conclude that native valve aspergillus infective endocarditis is uniformly fatal without surgical intervention and antifungal therapy.

Aged↗
PubMed2000

A pilot study of penicillin skin testing in patients with a history of penicillin allergy admitted to a medical ICU.

BACKGROUND: Penicillin skin testing is an accurate method to determine whether a person with a history of penicillin allergy is at risk of having an immediate reaction to penicillin. A patient with a negative reaction to a skin test may be able to use a penicillin compound safely, which could reduce the use of broad-spectrum antibiotics in this patient population. METHODS: We prospectively studied all patients with histories of penicillin allergy who were admitted to a medical ICU during a 3-month period and who received antibiotics. Skin testing was performed with benzylpenicilloyl polylysine and penicillin G. We determined the incidence of true allergy, the percentage of patients in whom antibiotic coverage was modified, and the safety of the test. RESULTS: Two hundred fifty-seven patients were admitted to the medical ICU of The Cleveland Clinic Foundation during the study period. Twenty-four patients (9%), labeled as penicillin allergic and receiving antibiotics, were enrolled. Three patients (13%, 3 of 21) gave histories of type I reaction to penicillin and were not skin tested. Twenty patients (95%, 20 of 21) had negative skin test reactions to penicillin and positive skin test reactions to histamine control. One patient (4%, 1 of 21) with negative skin test reactions to both penicillin and histamine control had a test dose challenge with piperacillin that was well tolerated. There were no adverse events. Antibiotic coverage was changed in 10 patients (48%) as a result of skin testing. CONCLUSION: Most patients with histories of allergy to penicillin have negative reactions to skin tests and may receive penicillin safely. Penicillin skin testing can be utilized as a safe and effective strategy to reduce the use of broad-spectrum antibiotics.

Adult↗
PubMed1999

Native lung pneumonectomy for invasive pulmonary aspergillosis following lung transplantation: a case report.

Pulmonary aspergillosis occurs most commonly as a consequence of immunosuppression in recipients of pulmonary transplantation and is associated with a high mortality. It affects the native lung more commonly than the transplanted lung in single lung transplant patients. Infection often progresses despite aggressive medical therapy. The cornerstone of treatment of acute, semi-invasive, and invasive pulmonary aspergillosis (IPA) is medical, with intravenous amphotericin B, and oral itraconazole either as isolated or combined therapy. While newer, and more expensive liposomal forms of amphotericin B have been used to enhance tissue penetration and minimize renal toxicity, an appreciable improvement in clinical outcome has not been reported. The role of surgery in localized pulmonary aspergillus infection is well recognized, but remains undefined in immunosuppressed patients. We report a case where a pneumonectomy was performed for progressive, refractory angioinvasive aspergillosis in a lung transplant recipient whose disease progressed despite conventional antifungal therapy.

Aspergillosis↗
PubMed1999

Clinical significance of Candida species isolated from cerebrospinal fluid following neurosurgery.

Twenty-one patients for whom adequate clinical data were available were identified in a retrospective review of cases of Candida species isolated from cerebrospinal fluid (CSF) following neurosurgery; 86% had indwelling cerebrospinal devices (shunts). Candida species were isolated from multiple CSF samples from 10 patients; CSF samples from seven of 10 were initially drawn through indwelling devices and those from nine of 10 were obtained by subsequent lumbar punctures. All of these patients were treated with antifungals, although therapy was delayed in 50% of cases until the second positive culture was reported. In 11 cases, Candida was the only isolate recovered from CSF samples drawn through indwelling devices; cultures of subsequent CSF samples obtained by lumbar puncture were negative in 10 of 11 cases. Only two patients for whom a single culture was positive for Candida species were treated with antifungals (both of whom were symptomatic), and none of the untreated patients died of infection. The clinical significance of a single positive CSF sample drawn through an indwelling device is difficult to assess, and a definitive diagnosis may require repeated cultures of CSF samples obtained by lumbar puncture.

Adolescent↗
PubMed1999

Should prophylaxis for Pneumocystis carinii pneumonia in solid organ transplant recipients ever be discontinued?

Solid organ transplant recipients are at risk for Pneumocystis carinii pneumonia (PCP), but the risk of PCP beyond 1 year is poorly defined. We identified 25 cases of PCP in 1,299 patients undergoing solid organ transplantation between 1987 and 1996 at The Cleveland Clinic Foundation (4.8 cases per 1,000 person transplant-years [PTY]). Ten (36%) of 28 PCP cases (transplantation was performed before 1987 in three cases) occurred > or = 1 year after transplantation, and no patient developed PCP while receiving prophylaxis for PCP. The incidence of PCP during the first year following transplantation was eight times higher than that during subsequent years. The highest rate occurred among lung transplant recipients (22 cases per 1,000 PTY), for whom the incidence did not decline beyond the first year of transplantation. We conclude that the incidence of PCP is highest during the first year after transplantation and differs by type of solid organ transplant. Extending the duration of PCP prophylaxis beyond 1 year may be warranted for lung transplant recipients.

Cost-Benefit Analysis↗
PubMed1999

Candida glabrata Fungemia. Clinical features of 139 patients.

Candida species are now the fourth leading cause of nosocomial bloodstream infection in hospitalized patients, and non-Candida albicans species now surpass Candida albicans. The clinical features of the most common non-Candida albicans species, Candida (Torulopsis) glabrata, have not been well studied. We retrospectively reviewed the clinical features of 139 patients with C. glabrata blood-stream infection over a period of 7 years. The mean age of patients was 62 years, and the most common admitting diagnoses were malignancy (28%) and coronary artery disease (18%). The most common identified portals of entry were abdominal (22%) and intravascular catheters (16%). At the time of fungemia, 63% of patients had fever, 45% had change in mental status, and 30% were in septic shock. Three of 50 patients examined by an ophthalmologist had chorioretinitis. The overall hospital mortality was 49%. Factors associated with increased mortality in a regression model were prior abdominal surgery (odds ratio [OR] = 2.8; 95% confidence interval [CI] = 1.2-6.3, p = 0.01), and an elevated creatinine (OR = 2.2; 95% CI = 1.0-4.7, p = 0.05). When early deaths (< or = 72 hours) were censored, amphotericin B treatment and total dose were associated with reduced mortality (OR = 0.2; 95% CI = 0.1-0.4, p < 0.001). Nosocomial C. glabrata fungemia is not just a disease of debilitated and neutropenic patients, but affects a wide variety of patients and is associated with a high mortality.

Aged↗
PubMed1999

Immunogenicity of hepatitis A vaccine in decompensated liver disease.

OBJECTIVE: Hepatitis A can cause decompensation and death in patients with previous liver injury. The hepatitis A vaccine is recommended for patients with chronic liver disease. The aim of this study was to screen, immunize, and measure the safety and antibody response of the hepatitis A vaccine in liver failure and liver transplant patients. METHODS: This was a prospective immunization trial at a referral center for liver disease and liver transplantation. A total of 193 patients with severe chronic liver disease were screened and 24 patients were vaccinated. Sixteen end stage liver disease patients were compared with eight liver transplant patients. Hepatitis A vaccinations using 1440 ELISA units were given at 0 and 2 months. Serum hepatitis A antibody titers were measured after each vaccine dose. An antibody response > or = 33 mIU/ml was considered protective. RESULTS: Screening seropositive rate was 70 of 193 (36%) and 24 patients were available for vaccination. The median antibody titer was markedly lower in liver transplant patients, 0.0 mIU/ml compared to liver failure patients 34.7 mIU/ml (p < 0.001). Liver transplant recipients did not respond to the vaccine (0 of eight patients) compared with seven of 14 liver failure patients (seroconversion rate 50%, p = 0.02). CONCLUSIONS: Liver failure significantly reduces the antibody response to hepatitis A vaccine, and liver transplant recipients were unable to respond to the vaccine. Although this study was small, immunization should be considered early for susceptible patients with chronic liver disease because the development of liver failure may blunt the immunogenicity of the vaccine.

Adult↗
PubMed1999

Analgesic efficacy and pharmacokinetics of ketoprofen administered into a surgical site.

A series of three clinical trials in the oral surgery model evaluated the analgesic efficacy and pharmacokinetics of ketoprofen administered locally as a strategy for decreasing systemic exposure to nonsteroidal anti-inflammatory drugs (NSAIDs). A gel formulation was administered directly into extraction sites 1 hour following oral surgery, and pain intensity was evaluated for 6 hours. Significantly less pain was seen following peripheral administration of both 10 and 30 mg ketoprofen in comparison to the placebo. In a second study, peripheral administration of the 1 mg dose resulted in greater analgesia than oral administration of the same dose formulation or the placebo. The third study demonstrated lower plasma drug levels following the peripheral route of administration in comparison to oral administration of the same dose or ingestion of a 25 mg oral capsule. These data indicate that administration of an NSAID to a peripheral site of tissue injury results in greater analgesia than oral administration and suggests the potential for less drug toxicity through lower circulating drug levels.

Administration, Oral↗
PubMed1999

Antihyperalgesic effect of the N-methyl-D-aspartate receptor antagonist dextromethorphan in the oral surgery model.

Peripheral neuronal barrage from tissue injury produces central nervous system hyperexcitability through the activation of N-methyl-D-aspartate (NMDA) receptor sites by excitatory amino acids and neuropeptides. This study evaluated if attenuation of NMDA receptor activation with dextromethorphan (DM) suppresses the postoperative development of hyperalgesia. Seventy-five patients undergoing oral surgery in a parallel-group, double-blind study randomly received either a placebo or the maximally tolerated dose of DM administered orally prior to and continuing for 48 hours following surgery. Pain as measured by category, visual analog, and verbal descriptor scales was not significantly different between groups during the first 6 hours following surgery. However, pain at 48 hours was decreased in the DM group as measured by scales for pain intensity and unpleasantness. Subjects in the DM group also self-administered fewer acetaminophen tablets for unrelieved pain over 24 to 48 hours postoperatively. The results suggest that DM at maximally tolerated doses does not produce an analgesic effect in the immediate postoperative period but reduces pain at 48 hours. This may be related to antagonism of NMDA receptors necessary for the expression of hyperalgesia associated with noxious afferent input postoperatively.

Adult↗
PubMed1999

Antiphospholipid antibody syndrome in a patient with neurosarcoidosis.

The case of a 56-year-old woman who developed neurosarcoidosis and was discovered to have inferior vena cava and lower extremity thromboses is described. She was found to have anticardiolipin antibodies. This newly described association of antiphospholipid antibody syndrome with sarcoidosis is discussed and the relevant literature reviewed.

Antiphospholipid Syndrome↗
PubMed1999

Risk factors for an outbreak of multi-drug-resistant Acinetobacter nosocomial pneumonia among intubated patients.

INTRODUCTION: Acinetobacter baumanii is a Gram-negative coccobacillus that is normally a commensal pathogen but can be a nosocomial pathogen. An epidemiologic study was performed to investigate an outbreak of A baumanii that occurred in our medical intensive care unit (MICU) from March to September 1995. METHODS: A case-control study was performed by retrospective chart review, comparing case patients to randomly selected patients who were mechanically ventilated in the MICU for at least 1 week during the outbreak. A case patient was defined as any patient with an Acinetobacter infection in which the epidemic strain was considered to be a pathogen. The epidemic strain was defined by its antibiogram. Case patients and control patients were compared for age, gender, underlying disease, acute physiology and chronic health evaluation III score, length of MICU stay, prior antibiotic use, presence of fever, sepsis, type of pulmonary infiltrate, and outcome. Environmental and hand-washing studies also were performed during the period of the outbreak. Molecular typing was performed on available bloodstream isolates. RESULTS: There were 15 cases of A baumanii nosocomial pneumonia. Fifty percent were bacteremic; one chart was unavailable for review. Twenty-nine patients were identified as control patients. The mean age for case patients was 50 (range, 21 to 84). The mean duration of time from admission to the ICU to infection was 12.8 days (range, 4 to 40). Sepsis developed in 35% of the case patients. Forty-three percent of the case patients died during their hospitalization, with two of those deaths attributed to Acinetobacter infection. Univariate analysis showed that prior use of ceftazidime was associated with infection with Acinetobacter (11/14 case patients compared to 11/29 control patients; p < 0.01). Pulsed-field gel electrophoresis revealed two strains to be responsible for the outbreak. Hand washing was performed before patient contact by only 10% of health-care workers, and only 32% washed their hands after patient contact. CONCLUSION: The use of ceftazidime was associated with an increased risk of nosocomial pneumonia with resistant strains of Acinetobacter. Health-care workers need to improve compliance with hand-washing recommendations.

Acinetobacter Infections↗
PubMed1998

Secular trends in nosocomial bloodstream infections in a 55-bed cardiothoracic intensive care unit.

BACKGROUND: Although bloodstream infections (BSIs) occur more frequently in intensive care unit patients than in ward patients, most studies of nosocomial BSIs in critically ill patients have not distinguished between intensive care unit populations beyond surgical, medical, and pediatric patients. METHODS: The primary objective of this study was to characterize the secular trends in rates of nosocomial BSIs for all pathogens among patients admitted to a busy cardiothoracic intensive care unit in a single tertiary care institution between January 1986 and December 1995. Patients with nosocomial BSIs were identified through continual prospective surveillance. RESULTS: A total of 40,207 patients were admitted to the cardiothoracic intensive care unit during the 10-year study period, and 804 episodes of nosocomial BSIs among 681 patients were identified. The mean crude BSI infection rate was 6.0 per 1,000 patient-care days and increased linearly during the study period (range, 4.4 to 8.1 per 1000 patient-care days), and approached statistical significance (p value = 0.07). The most common organisms causing BSIs were Staphylococcus aureus (12%), coagulase-negative staphylococci (11%), Candida albicans (11%), Pseudomonas aeruginosa (10%), and Enterococci (9%). The leading sources of nosocomial BSIs were primary BSIs (33%), intravascular devices (27%), lower respiratory tract infections (17%), and surgical wound infections (12%). The etiologic fraction or the proportion of deaths in cardiothoracic intensive care unit patients with BSIs was 15-fold higher than those patients without BSIs (37% versus 2.5%, p < 0.001). CONCLUSIONS: Rates of nosocomial BSIs among patients in our cardiothoracic intensive care unit have increased linearly during the past decade and patients with nosocomial BSIs have an increased risk of in hospital mortality.

Candida albicans↗
PubMed1998

The substance P receptor antagonist CP-99,994 reduces acute postoperative pain.

BACKGROUND: Animal studies suggest that substance P, a peptide that preferentially activates the neurokinin-1 (NK1) receptor, is involved in pain transmission, with particular importance in pain after inflammation. METHODS: The analgesic efficacy of CP-99,994, a NK1 receptor antagonist, was compared with ibuprofen and placebo in 78 subjects undergoing third molar extraction. The initial 60 subjects randomly received 1 of 3 possible treatments in a double-blind fashion before oral surgery: 750 microg/kg CP-99,994 infused intravenously over 5 hours on a tapering regimen starting 2 hours before surgery, 600 mg oral ibuprofen 30 minutes before surgery, or placebo. In a second study, 18 subjects were randomized to the same regimens starting 30 minutes before surgery to maximize the amount of CP-99,994 circulating during pain onset. RESULTS: In the first study, ibuprofen significantly reduced pain, as measured by visual analog scale, from 90 to 240 minutes postoperatively compared with placebo. CP-99,994 produced analgesia that was significant at 90 minutes (P < 0.01 compared with placebo), but not at subsequent time points. In the second study, ibuprofen and, to a lesser extent, CP-99,994 significantly suppressed pain in comparison to placebo at 60, 90, and 120 minutes (P < 0.05). The incidence of side effects was similar across groups. CONCLUSIONS: This replicate demonstration that a NK1 receptor blocker relieves clinical pain supports the hypothesis that substance P contributes to the generation of pain in humans. The reduction in postoperative pain at doses not producing side effects suggests that NK1 antagonists may be clinically useful.

Acute Disease↗
PubMed1998

Viridans streptococcal bacteremia after esophageal stricture dilation.

BACKGROUND: The incidence of bacteremia with organisms that may cause infective endocarditis after esophageal stricture dilation is unknown. There is disagreement among physicians regarding the need for antibiotic prophylaxis for patients with valvular heart disease undergoing dilation. Our aim was to determine the frequency and duration of bacteremia associated with esophageal stricture dilation. METHODS: Blood cultures were obtained before and after stricture dilation in patients without valvular heart disease and in a control group of patients undergoing upper endoscopy without dilation. RESULTS: A total of 103 patients undergoing dilation and 50 control patients were studied; 22 of 103 patients (21%) undergoing dilation had at least one post-procedure blood culture positive for viridans streptococcus, compared with 1 of 50 (2%) of control patients (p = 0. 001). Blood cultures obtained 1 minute after stricture dilation were positive for viridans streptococcus in 19 of 81 (23%), in 16 of 96 (17%) 5 minutes post-dilation, and in 3 of 63 (5%) 20 to 30 minutes post-dilation. Of the 19 patients with viridans streptococcus bacteremia 1 minute after dilation, cultures were still positive in 14 of 19 (74%) at 5 minutes and in 2 of 19 (10%) 20 to 30 minutes post-dilation. CONCLUSIONS: These data support the use of antibiotic prophylaxis before esophageal stricture dilation for patients with valvular heart disease at risk for the development of infective endocarditis.

Antibiotic Prophylaxis↗
PubMed1998

Determinants of surgical site infection after breast surgery.

BACKGROUND: Surgical site infection (SSI) after breast procedures may result in significant morbidity, psychologic trauma, and additional cost, SSI rates in patients at the Cleveland Clinic Foundation having biopsy, partial mastectomy, or modified radical mastectomy were higher during April and May 1995 than during the previous 12 months (8 infections for 74 procedures [10.8%] vs 10 for 378 [2.6%]; p < 0.006). Since 1993 one surgeon has performed most of these procedures, with no change in operative technique, skin preparation, or surgical team. A case-control study was performed to identify risk factors for infection. METHODS: A case patient was defined as any patient having a breast procedure from April 1994 through May 1995 with culture of a pathogen from surgical site drainage or aspiration or with erythema or presence of cellulitis treated by incision and drainage and/or antibiotic therapy. Randomly selected control patients were matched by time and procedure. There were 18 case patients and 37 control patients. RESULTS: Factors associated with SSI were obesity (78% of cases vs 40% of controls; p = 0.02) and older age (mean 66 years in cases vs 56 years in controls; p = 0.005). After introduction of cefazolin sodium prophylaxis, SSI rate was reduced to 0.9% (3 infections for 332 procedures). CONCLUSIONS: Host factors may contribute to SSI in breast procedures. Cefazolin sodium prophylaxis was useful in preventing SSI after breast surgery.

Age Distribution↗