Thomas K. Aldrich

The incidence of infectious complications of central venous catheters at the subclavian, internal jugular, and femoral sites in an intensive care unit population*

Objective:The objective was to assess the risk of central venous catheter infection with respect to the site of insertion in an intensive care unit population. The subclavian, internal jugular, and femoral sites were studied. Design:An epidemiologic, prospective, observational study. Setting:The setting is a well-functioning intensive care unit under a unified critical care medicine division in a university teaching hospital. Critical care medicine attendings and fellows covered on site 17 and 24 hrs per day, respectively. Patients:Patients were critically ill. All patients were triaged into the intensive care unit by on-site critical care medicine fellows. Interventions:None. Measurements and Main Results:In an intensive care unit population, we prospectively studied the incidence of central venous catheter infection and colonization at the subclavian, internal jugular, and femoral sites. The optimal insertion site for each individual patient was selected by experienced intensive care physicians (critical care medicine attendings and fellows). All of the operators were proficient in inserting catheters at all three sites. Confounding factors were eliminated; there were a limited number of experienced operators inserting the catheters, a uniform protocol stressing strict sterile insertion was enforced, and standardized continuous catheter care was provided by dedicated intensive care nurses proficient in all aspects of central venous catheter care. Two groups of patients were analyzed. Group 1 was patients with one catheter at one site, and group 2 was patients with catheters at multiple sites. Group 1 was the primary analysis, whereas group 2 was supporting. A total of 831 central venous catheters and 4,735 catheter days in 657 patients were studied. The incidence of catheter infection (4.01/1,000 catheter days, 2.29% catheters) and colonization (5.07/1,000 catheter days, 2.89% catheters) was low overall. In group 1, the incidence of infection was subclavian: 0.881 infections/1,000 catheter days (0.45%), internal jugular: 0/1,000 (0%), and femoral: 2.98/1,000 (1.44%; p = .2635). The incidence of colonization was subclavian: 0.881 colonization/1,000 catheter days (0.45%), internal jugular: 2.00/1,000 (1.05%), and femoral: 5.96/1,000 (2.88%, p = .1338). There was no statistically significant difference in the incidence of infection and colonization or duration of catheters (p = .8907) among the insertion sites. In group 2, there was also no statistically significant difference in the incidence of infection and colonization among the three insertion sites. Conclusion:In an intensive care unit population, the incidence of central venous catheter infection and colonization is low overall and, clinically and statistically, is not different at all three sites when optimal insertion sites are selected, experienced operators insert the catheters, strict sterile technique is present, and trained intensive care unit nursing staff perform catheter care.

Lung Function in Rescue Workers at the World Trade Center after 7 Years

BACKGROUND The terrorist attacks on the World Trade Center on September 11, 2001, exposed thousands of Fire Department of New York City (FDNY) rescue workers to dust, leading to substantial declines in lung function in the first year. We sought to determine the longer-term effects of exposure. METHODS Using linear mixed models, we analyzed the forced expiratory volume in 1 second (FEV(1)) of both active and retired FDNY rescue workers on the basis of spirometry routinely performed at intervals of 12 to 18 months from March 12, 2000, to September 11, 2008. RESULTS Of the 13,954 FDNY workers who were present at the World Trade Center between September 11, 2001, and September 24, 2001, a total of 12,781 (91.6%) participated in this study, contributing 61,746 quality-screened spirometric measurements. The median follow-up was 6.1 years for firefighters and 6.4 years for emergency-medical-services (EMS) workers. In the first year, the mean FEV(1) decreased significantly for all workers, more for firefighters who had never smoked (a reduction of 439 ml; 95% confidence interval [CI], 408 to 471) than for EMS workers who had never smoked (a reduction of 267 ml; 95% CI, 263 to 271) (P<0.001 for both comparisons). There was little or no recovery in FEV(1) during the subsequent 6 years, with a mean annualized reduction in FEV(1) of 25 ml per year for firefighters and 40 ml per year for EMS workers. The proportion of workers who had never smoked and who had an FEV(1) below the lower limit of the normal range increased during the first year, from 3% to 18% for firefighters and from 12% to 22% for EMS workers, stabilizing at about 13% for firefighters and 22% for EMS workers during the subsequent 6 years. CONCLUSIONS Exposure to World Trade Center dust led to large declines in FEV(1) for FDNY rescue workers during the first year. Overall, these declines were persistent, without recovery over the next 6 years, leaving a substantial proportion of workers with abnormal lung function.

Weaning from mechanical ventilation: adjunctive use of inspiratory muscle resistive training

We used inspiratory resistive training (IRT) in an effort to improve the respiratory muscle endurance of 27 patients with respiratory failure who had failed repeated weaning attempts using standard techniques. Seven patients had primary neuromuscular diseases; the other 20 had primary lung diseases. All patients had stable respiratory failure, without gross malnutrition or electrolyte disorders. Their best initial T-piece duration averaged 6.4 +/- 8.4 (SD) h, with pHa 7.33 +/- 0.09 and PCO2 63 +/- 4 torr at the end of the T-piece trial. We provided a mean of five weekly training sessions of spontaneous breathing through an adjustable nonlinear resistor, with gradually increasing duration and resistance. When initial T-piece tolerance was less than 2 h, two to ten breaths of mechanical ventilation were provided during IRT sessions. No training session exceeded 30 min, and mechanical ventilation was provided between IRT sessions. Under this regimen, maximal inspiratory pressure improved from -37 +/- 15 to -46 +/- 15 cm H2O (p less than .001) and vital capacity improved from 561 +/- 325 to 901 +/- 480 ml (p less than .001). Twelve of the 27 patients were successfully weaned after 10 to 46 days; five more were weaned to nocturnal ventilation, for a total of 63%. We conclude that IRT can improve respiratory muscle strength and endurance in patients with respiratory failure, and can allow many of them to be weaned from mechanical ventilation.

Obstructive Airways Disease With Air Trapping Among Firefighters Exposed to World Trade Center Dust

BACKGROUND The World Trade Center (WTC) collapse produced a massive exposure to respirable particulates in New York City Fire Department (FDNY) rescue workers. This group had spirometry examinations pre-September 11, 2001, and post-September 11, 2001, demonstrating declines in lung function with parallel declines in FEV(1) and FVC. To date, the underlying pathophysiologic cause for this has been open to question. METHODS Of 13,234 participants in the FDNY-WTC Monitoring Program, 1,720 (13%) were referred for pulmonary subspecialty evaluation at a single institution. Evaluation included 919 full pulmonary function tests, 1,219 methacholine challenge tests, and 982 high-resolution chest CT scans. RESULTS At pulmonary evaluation (median 34 months post-September 11, 2001), median values were FEV(1) 93% predicted (interquartile range [IQR], 83%-101%), FVC 98% predicted (IQR, 89%-106%), and FEV(1)/FVC 0.78 (IQR, 0.72-0.82). The residual volume (RV) was 123% predicted (IQR, 106%-147%) with nearly all participants having normal total lung capacity, functional residual capacity, and diffusing capacity of carbon monoxide. Also, 1,051/1,720 (59%) had obstructive airways disease based on at least one of the following: FEV(1)/FVC, bronchodilator responsiveness, hyperreactivity, or elevated RV. After adjusting for age, gender, race, height and weight, and tobacco use, the decline in FEV(1) post-September 11, 2001, was significantly correlated with increased RV percent predicted (P < .0001), increased bronchodilator responsiveness (P < .0001), and increased hyperreactivity (P = .0056). CT scans demonstrated bronchial wall thickening that was significantly associated with the decline in FEV(1) post-September 11, 2001 (P = .024), increases in hyperreactivity (P < .0001), and increases in RV (P < .0001). Few had evidence for interstitial disease. CONCLUSIONS Airways obstruction was the predominant physiologic finding underlying the reduction in lung function post-September 11, 2001, in FDNY WTC rescue workers presenting for pulmonary evaluation.

Smoking cessation in the elderly

Today, two generations after the first Surgeon Generals report, and with abundant evidence of the catastrophic consequences of smoking, no serious person can be unaware that smokers risk their lives and health. We also know that quitting smoking--at any age--promises significant health benefits. When offered the tools they need, older smokers quit smoking at rates comparable to those of younger smokers despite their skepticism, fatalism, and self-doubt. Older smokers should be encouraged to enter programs that stress the health benefits derived and identify the risks they are avoiding by quitting smoking. These programs establish quit dates, use sound behavioral modification techniques, provide strategies for stress management and relaxation, treat withdrawal symptoms, and provide regular and continuing follow-up. The patient is asked to make an existential change, and the physician should provide encouragement and promote self-confidence by emphasizing that, despite setbacks, with repeated efforts, success can be achieved. Clinicians can influence patients to quit smoking, and they should.

Early assessment of cancer outcomes in New York City firefighters after the 9/11 attacks: an observational cohort study.

BACKGROUND The attacks on the World Trade Center (WTC) on Sept 11, 2001 (9/11) created the potential for occupational exposure to known and suspected carcinogens. We examined cancer incidence and its potential association with exposure in the first 7 years after 9/11 in firefighters with health information before 9/11 and minimal loss to follow-up. METHODS We assessed 9853 men who were employed as firefighters on Jan 1, 1996. On and after 9/11, person-time for 8927 firefighters was classified as WTC-exposed; all person-time before 9/11, and person-time after 9/11 for 926 non-WTC-exposed firefighters, was classified as non-WTC exposed. Cancer cases were confirmed by matches with state tumour registries or through appropriate documentation. We estimated the ratio of incidence rates in WTC-exposed firefighters to non-exposed firefighters, adjusted for age, race and ethnic origin, and secular trends, with the US National Cancer Institute Surveillance Epidemiology and End Results (SEER) reference population. CIs were estimated with overdispersed Poisson models. Additional analyses included corrections for potential surveillance bias and modified cohort inclusion criteria. FINDINGS Compared with the general male population in the USA with a similar demographic mix, the standardised incidence ratios (SIRs) of the cancer incidence in WTC-exposed firefighters was 1·10 (95% CI 0·98-1·25). When compared with non-exposed firefighters, the SIR of cancer incidence in WTC-exposed firefighters was 1·19 (95% CI 0·96-1·47) corrected for possible surveillance bias and 1·32 (1·07-1·62) without correction for surveillance bias. Secondary analyses showed similar effect sizes. INTERPRETATION We reported a modest excess of cancer cases in the WTC-exposed cohort. We remain cautious in our interpretation of this finding because the time since 9/11 is short for cancer outcomes, and the reported excess of cancers is not limited to specific organ types. As in any observational study, we cannot rule out the possibility that effects in the exposed group might be due to unidentified confounders. Continued follow-up will be important and should include cancer screening and prevention strategies. FUNDING National Institute for Occupational Safety and Health.

Physician-diagnosed respiratory conditions and mental health symptoms 7-9 years following the World Trade Center disaster

BACKGROUND This study examines the prevalence of physician-diagnosed respiratory conditions and mental health symptoms in firefighters and emergency medical service workers up to 9 years after rescue/recovery efforts at the World Trade Center (WTC). METHODS We analyzed Fire Department of New York (FDNY) physician and self-reported diagnoses by WTC exposure and quintiles of pulmonary function (FEV1% predicted). We used screening instruments to assess probable post-traumatic stress disorder (PTSD) and probable depression. RESULTS FDNY physicians most commonly diagnosed asthma (8.8%) and sinusitis (9.7%). The highest prevalence of physician-diagnosed obstructive airway disease (OAD) was in the lowest FEV1% predicted quintile. Participants who arrived earliest on 9/11 were more likely to have physician-diagnosed asthma (OR = 1.4). Seven percent had probable PTSD. 19.4% had probable depression. CONCLUSIONS Self-reported and physician-diagnosed respiratory conditions remain common, especially among those who arrived earliest at the WTC site. OAD was associated with the lowest pulmonary function. Since respiratory and mental health conditions remain prevalent, ongoing monitoring and treatment is important.

High-Dose Intramuscular Triamcinolone in Severe, Chronic, Life-Threatening Asthma

BACKGROUND Despite oral corticosteroid therapy, some patients with asthma have frequent exacerbations requiring emergency room visits, hospitalization, and occasionally, mechanical ventilation. We compared the effects of high-dose intramuscular triamcinolone with oral prednisone in patients with severe chronic asthma. METHODS In a double-blind, placebo-controlled, cross-over study that spanned all seasons, we treated 12 patients with high-dose intramuscular triamcinolone (360 mg over the first three days of the treatment period) or low-dose oral prednisone (median dose, 12.5 mg per day throughout the period; range 0 to 30). The two three-month treatment periods were separated by a three-month washout period. During all periods the patients were allowed to take additional doses of prednisone for acute exacerbations of asthma. RESULTS After receiving triamcinolone, the patients had significantly better peak expiratory flow rates than while receiving prednisone (the average [+/- SEM] weekly percent of the predicted value during the triamcinolone period was 91.5 +/- 6.9, as compared with 75.0 +/- 5.9 for the prednisone period; P less than 0.05). During the prednisone period there were 21 emergency room visits and 10 hospitalizations, but there were none during the triamcinolone period (P less than 0.05). There were two episodes of ventilatory failure during the prednisone period. Total steroid doses were significantly smaller during the triamcinolone period than during the prednisone period (P less than 0.04). Steroidal side effects were more pronounced after treatment with triamcinolone than after treatment with prednisone (P less than 0.1). CONCLUSIONS We conclude that high-dose intramuscular triamcinolone is more effective than low-dose prednisone in patients with severe, chronic, life-threatening asthma, but steroidal side effects are somewhat worse.

Inhibition of Capsaicin‐Induced Cough by the γ‐Aminobutyric Acid Agonist Baclofen

γ‐aminobutyric acid (GABA) is a central inhibitory neurotransmitter that also exists in the lungs. The GABA‐agonist baclofen has been shown to have antitussive activity via a central mechanism in animals. Recently it was demonstrated that a 14‐day course of baclofen given three times daily significantly inhibits the cough reflex in healthy volunteers. Because of the prolonged antitussive effect of baclofen that has been previously observed, the present study was conducted to evaluate the antitussive effect of low‐dose, oral baclofen given once daily. Forty‐one healthy volunteers were randomly assigned in a double‐blind manner to receive a 28‐day course of baclofen, either 10 mg or 20 mg once daily, or placebo. Subjects underwent cough challenge testing with inhaled capsaicin to establish baseline cough reflex sensitivity, and subsequently after 14 and 28 days of therapy. Subjects receiving baclofen 20 mg daily demonstrated significant inhibition of cough sensitivity after 14 days and after 28 days of therapy compared with baseline. Neither placebo nor baclofen 10 mg daily had a significant effect on cough sensitivity. No serious side effects were experienced by any study participant. These results confirm the recent observation that baclofen has significant antitussive activity in humans. Further, once‐daily administration of a relatively low dose of baclofen is sufficient to achieve significant cough inhibition, although at least 14 to 28 days of therapy may be required to attain maximal antitussive effect. These results support further investigation of baclofen or other GABA‐agonists as potential therapeutic agents for chronic, nonproductive cough.

Metabolic syndrome biomarkers predict lung function impairment: A nested case-control study

RATIONALE Cross-sectional studies demonstrate an association between metabolic syndrome and impaired lung function. OBJECTIVES To define if metabolic syndrome biomarkers are risk factors for loss of lung function after irritant exposure. METHODS A nested case-control study of Fire Department of New York personnel with normal pre-September 11th FEV(1) and who presented for subspecialty pulmonary evaluation before March 10, 2008. We correlated metabolic syndrome biomarkers obtained within 6 months of World Trade Center dust exposure with subsequent FEV(1). FEV(1) at subspecialty pulmonary evaluation within 6.5 years defined disease status; cases had FEV(1) less than lower limit of normal, whereas control subjects had FEV(1) greater than or equal to lower limit of normal. MEASUREMENTS AND MAIN RESULTS Clinical data and serum sampled at the first monitoring examination within 6 months of September 11, 2001, assessed body mass index, heart rate, serum glucose, triglycerides and high-density lipoprotein (HDL), leptin, pancreatic polypeptide, and amylin. Cases and control subjects had significant differences in HDL less than 40 mg/dl with triglycerides greater than or equal to 150 mg/dl, heart rate greater than or equal to 66 bpm, and leptin greater than or equal to 10,300 pg/ml. Each increased the odds of abnormal FEV(1) at pulmonary evaluation by more than twofold, whereas amylin greater than or equal to 116 pg/ml decreased the odds by 84%, in a multibiomarker model adjusting for age, race, body mass index, and World Trade Center arrival time. This model had a sensitivity of 41%, a specificity of 86%, and a receiver operating characteristic area under the curve of 0.77. CONCLUSIONS Abnormal triglycerides and HDL and elevated heart rate and leptin are independent risk factors of greater susceptibility to lung function impairment after September 11, 2001, whereas elevated amylin is protective. Metabolic biomarkers are predictors of lung disease, and may be useful for assessing risk of impaired lung function in response to particulate inhalation.