Mitochondria COI-based genetic diversity of the cotton leafhopper Amrasca biguttula biguttula (Ishida) populations from India.

Amrasca biguttula biguttula (Ishida), the cotton leafhopper, is a polyphagous insect pest of Asia and Southeast Asian countries. We sequenced a mitochondrial COI gene fragment from 67 individuals of cotton leafhopper collected from 7 major cotton growing states of North, Central, and South India. Genetic divergence analysis of leaf hopper population across India confirmed the presence of single species. Thirty haplotypes, in total, were determined across different regions of India. While population from North India was dominated by single haplotype, the south and central Indian populations show dispersion of different haplotypes across the region. The neutrality test rejection for the north Indian population also suggests population expansion. The genetic differentiation and gene flow analysis together confirmed the phylogeographic structure of the A. biguttula biguttula Ishida as isolated by distance.

Guidelines for the Appropriate Use of Bedside General and Cardiac Ultrasonography in the Evaluation of Critically Ill Patients-Part I: General Ultrasonography.

OBJECTIVE: To establish evidence-based guidelines for the use of bedside ultrasound by intensivists and specialists in the ICU and equivalent care sites for diagnostic and therapeutic purposes for organs of the chest, abdomen, pelvis, neck, and extremities. METHODS: The Grading of Recommendations, Assessment, Development and Evaluation system was used to determine the strength of recommendations as either strong or conditional/weak and to rank the "levels" of quality of evidence into high (A), moderate (B), or low (C) and thus generating six "grades" of recommendation (1A-1B-1C-2A-2B-2C). Grading of Recommendations, Assessment, Development and Evaluation (GRADE) was used for all questions with clinically relevant outcomes. RAND appropriateness method, incorporating modified Delphi technique, was used in steps of GRADE that required panel judgment and for those based purely on expert consensus. The process was conducted by teleconference and electronic-based discussion, following clear rules for establishing consensus and agreement/disagreement. Individual panel members provided full disclosure and were judged to be free of any commercial bias. The process was conducted independent of industry funding. RESULTS: Twenty-four statements regarding the use of ultrasound were considered-three did not achieve agreement and nine were approved as conditional recommendations (strength class 2). The remaining 12 statements were approved as strong recommendations (strength class 1). Each recommendation was also linked to its level of quality of evidence. Key strong recommendations included the use of ultrasonography for ruling-in pleural effusion and assisting its drainage, ascites drainage, ruling-in pneumothorax, central venous cannulation, particularly for internal jugular and femoral sites, and for diagnosis of deep venous thrombosis. Conditional recommendations were given to the use of ultrasound by the intensivist for diagnosis of acalculous cholecystitis, renal failure, and interstitial and parenchymal lung diseases. No recommendations were made regarding static (vs dynamic) ultrasound guidance of vascular access or the use of needle guide devices. CONCLUSIONS: There was strong agreement among a large cohort of international experts regarding several recommendations for the use of ultrasound in the ICU. Evidence-based recommendations regarding the appropriate use of this technology are a step toward improving patient outcomes in relevant patients.

Cardiac Vignette: Giant Left Atrial Appendage Aneurysm.

BACKGROUND: The left atrial appendage (LAA) is a vestigial structure located in the postero-lateral aspect of the left atrium. Aneurysmal enlargement of the LAA is pathological and can predispose to adverse events, including myocardial infarction, atrial fibrillation and systemic thromboembolism. The condition is rare and usually isolated, occurring in the absence of other cardiac defects. In this cardiac vignette, we describe a case of giant left atrial appendage in a middle aged female presenting with chest pain and explore the natural history, different investigative modalities as well as issues in clinical management of this condition.

Bacterial colonization increases daily symptoms in patients with chronic obstructive pulmonary disease.

RATIONALE: Respiratory pathogens are frequently isolated from the airways of patients with chronic obstructive pulmonary disease (COPD) in the absence of an exacerbation. This bacterial "colonization" by potential pathogens is associated with host inflammatory and immune responses, which could increase respiratory symptoms. OBJECTIVES: To study whether bacterial colonization impacts daily respiratory symptoms in COPD. METHODS: In a longitudinal prospective observational study of COPD, patients recorded daily symptoms electronically on the Breathlessness, Cough, and Sputum Scale (BCSS). Sputum cultures and quantitative polymerase chain reaction (PCR) were performed every 2 weeks. The relationship of BCSS and bacterial colonization was analyzed with generalized linear mixed effects models, after controlling for exacerbations, weather conditions, lung function, and demographic variables. MEASUREMENTS AND MAIN RESULTS: A total of 41 patients recorded daily symptoms for 12,527 days. The average BCSS score was higher during the periods of colonization, determined by sputum culture with one or more of the following pathogens: nontypeable Haemophilus influenzae, Moraxella catarrhalis, Streptococcus pneumoniae, and Pseudomonas aeruginosa, compared to periods without colonization (5.28 vs. 4.46; P = 0.008) after controlling for confounding variables. The finding did not change when colonization was defined by quantitative PCR (average BCSS, 4.77 vs. 4.25; P = 0.006). Sputum IL-8 levels were elevated with bacterial colonization. CONCLUSIONS: Even in the absence of clinical exacerbation, colonization by bacterial pathogens in COPD was associated with a clinically significant moderate increase in daily symptoms, likely mediated by increased airway inflammation. Novel therapies that decrease bacterial colonization in COPD could improve daily symptoms and quality of life.

Characteristics of patients with the "malignant obesity hypoventilation syndrome" admitted to an ICU.

BACKGROUND: The incidence of obesity in westernized nations is increasing at an alarming rate. We have noted an increasing number of patients admitted to our intensive care unit (ICU) with hypercapnic respiratory failure and multisystem organ dysfunction related to obesity. We have coined the term the malignant obesity hypoventilation syndrome (MOHS) to describe this entity. METHODS: We reviewed the hospital records of all patients who were admitted to our ICU over an 8-month period, with a body mass index (BMI) greater than 40 kg/m² and a PaCO2 greater than 45 mm Hg. We excluded patients with musculoskeletal disease, intrinsic lung disease, and those with >20 pack-year smoking history. RESULTS: Sixty-one patients (8% of all admissions) met the inclusion criteria for our study. The patients' mean BMI was 48.9 ± 8.6 kg/m². The patients' mean age was 59 ± 11; 47 (77%) were female and 56 (92%) were black. All patients were admitted to the ICU with hypercapnic respiratory failure. The patients had been admitted to our hospital on average 6 times over the previous 2 years; 75% had been erroneously diagnosed and treated for chronic obstructive pulmonary disease (COPD)/asthma and 86% had been treated with diuretics for congestive cardiac failure. All patients had type 2 diabetes and the metabolic syndrome. Three patients had a tracheotomy in place at admission and required mechanical ventilation. All of the remaining patients were treated with noninvasive bilevel positive airway pressure (BiPAP), with 23 patients failing BiPAP and requiring mechanical ventilation. Seven patients had a tracheotomy performed. On the basis of unexplained abnormalities of liver function tests, 39 patients (64%) were presumptively diagnosed with nonalcoholic steatohepatitis (NASH). Pulmonary function tests were suggestive of a restrictive pattern in all patients tested. By echocardiography 43 (71%) patients had left ventricular hypertrophy and 37 (61%) patients had features of left ventricular diastolic dysfunction. Forty-seven (77%) patients had pulmonary hypertension, which was moderate to severe (pulmonary systolic pressure >45 mm Hg) in 25 cases. All patients had an elevated C-reactive protein (9.4 ± 6.9 mg/dL), and all but 1 were vitamin D deficient (13.5 ± 8.5 ng/mL). Eleven patients (18%) died during the index hospitalization. CONCLUSIONS: MOHS is a serious multisystem disorder with a high mortality that appears to be relatively common, frequently misdiagnosed, and inadequately treated.

Pulmonary emergencies: pneumonia, acute respiratory distress syndrome, lung abscess, and empyema.

This article describes the clinical presentation of pneumonia, acute respiratory distress syndrome, lung abscess, and empyema: life-threatening infections of the pulmonary system. The etiology and risk factors for each of these conditions are described, diagnostic approaches are discussed, and evidence-based management options are reviewed.

Goal directed fluid therapy.

The cornerstone of treating patients with shock remains as it has for decades, intravenous fluids. Surprisingly, dosing intravenous fluid during resuscitation of shock remains largely empirical. Recent data suggests that early aggressive resuscitation of critically ill patients may limit and/or reverse tissue hypoxia, progression to organ failure and improve outcome. However, overzealous fluid resuscitation has been associated with increased complications, increased length of intensive care unit (ICU) and hospital stay and increased mortality. This review focuses on methods to assess fluid responsiveness and the application of these methods for goal directed fluid therapy in critically ill and peri-operative patients.

Inhaled nitric oxide as salvage therapy in massive pulmonary embolism: a case series.

Inhaled nitric oxide (INO) has been shown to preferentially lower resistance in the pulmonary vasculature. The relative selectiveness of INO in accomplishing this effect makes it an attractive drug to administer as salvage therapy in patients with acute right ventricular failure secondary to pulmonary embolism. We describe 4 cases in which INO was used as a temporizing agent to decrease right ventricular after-load following massive near-fatal pulmonary embolism. All 4 patients survived to hospital discharge.

Antibiotic resistance in sputum isolates of Streptococcus pneumoniae in chronic obstructive pulmonary disease is related to antibiotic exposure.

Streptococcus pneumoniae (S. pneumoniae) is recovered from sputum of patients with chronic obstructive pulmonary disease (COPD) during stable disease and exacerbations. In patients with community acquired pneumonia, antibiotic exposure in the prior 3-6 months is associated with recovery of antibiotic resistant isolates of S. pneumoniae. Whether the same relationship is seen in COPD is not known. From April 1994 to June 2004, 127 adults with COPD were enrolled in a prospective longitudinal study. Sputum isolates of S. pneumoniae were characterized with susceptibility testing and pulsed-field gel electrophoresis (PFGE). The relationship between antibiotic use in the previous 3 and 6 months with either new acquisition of a resistant pneumococcal isolate or development of resistance (4-fold increase in MIC) in a pre-existing colonizing pneumococcal strain was determined. A total of 194 pneumococcal isolates were recovered from 38 patients. Among 71 newly acquired and 4 resistance-emergent strains analyzed further, rates of resistance to penicillin (MIC ≥2), erythromycin (MIC ≥1), tetracycline (MIC ≥8) and trimethoprim/sulfamethoxazole (MIC ≥4) were 8%, 24%, 17% and 16% respectively. Flouroquinolone resistance was not seen. Among strains isolated from patients exposed to a macrolide within 6 months, 53.6% displayed erythromycin resistance vs. 14% of strains without such exposure (p = 0.00085). Similar associations were not seen for other antibiotics. Macrolide use in the previous 6 months is associated with macrolide resistance in sputum isolates of S. pneumoniae. Recent antibiotic exposure may help in determining appropriate antibiotic treatment in these patients.

Accuracy of autotitrating CPAP to estimate the residual Apnea-Hypopnea Index in patients with obstructive sleep apnea on treatment with autotitrating CPAP.

OBJECTIVE: Autotitrating continuous positive airway pressure (auto-CPAP) devices now have a smart card (a pocket-sized card with embedded integrated circuits which records data from the CPAP machine such as CPAP usage, CPAP pressure, large leak, etc.) which can estimate the Apnea-Hypopnea Index (AHI) on therapy. The aim of this study was to determine the accuracy of auto-CPAP in estimating the residual AHI in patients with obstructive sleep apnea (OSA) who were treated with auto-CPAP without a CPAP titration study. PATIENTS AND METHODS: We studied 99 patients with OSA from April 2005 to May 2007 who underwent a repeat sleep study using auto-CPAP. The estimated AHI from auto-CPAP was compared with the AHI from an overnight polysomnogram (PSG) on auto-CPAP using Bland-Altman plot and likelihood ratio analyses. A PSG AHI cutoff of five events per hour was used to differentiate patients optimally treated with auto-CPAP from those with residual OSA on therapy. RESULTS: Bland and Altman analysis showed good agreement between auto-CPAP AHI and PSG AHI. There was no significant bias when smart card estimates of AHI at home were compared to smart card estimates obtained in the sleep laboratory. An auto-CPAP cutoff for the AHI of six events per hour was shown to be optimal for differentiating patients with and without residual OSA with a sensitivity of 0.92 (95% confidence interval (CI) 0.76 to 0.98) and specificity of 0.90 (95% CI 0.82 to 0.95) with a positive likelihood ratio (LR) of 9.6 (95% CI 5.1 to 21.5) and a negative likelihood ratio of 0.085 (95% CI 0.02 to 0.25). Auto-CPAP AHI of eight events per hour yielded the optimal sensitivity (0.94, 95% CI 0.73 to 0.99) and specificity (0.90, 95% CI 0.82 to 0.95) with a positive LR of 9.6 (95% CI 5.23 to 20.31) and a negative LR of 0.065 (95% CI 0.004 to 0.279) to identify patients with a PSG AHI of > or = 10 events per hour. CONCLUSION: Auto-CPAP estimate of AHI may be used to estimate residual AHI in patients with OSA of varying severity treated with auto-CPAP.

Hypoxemia in patients on chronic opiate therapy with and without sleep apnea.

OBJECTIVE: Animal models have shown a quantal slowing of respiratory pattern when exposed to opioid agonist, in a pattern similar to that observed in central sleep apnea. We postulated that opioid-induced hypoventilation is more likely to be associated with sleep apnea rather than hypoventilation alone. Since we did not have a direct measure of hypoventilation we used hypoxemia as an indirect measure reasoning that significant hypoventilation would not occur in the absence of hypoxemia. METHODS: We conducted a retrospective analysis of 98 consecutive patients on chronic opioid medications who were referred for overnight polysomnography. All patients on chronic opioids seen in the chronic pain clinic were referred for a sleep study regardless of whether they had sleep symptoms or not. Sleep-related hypoxemia was defined as arterial oxyhemoglobin saturation of less than 90% for more than 5 min with a nadir of

Sleep-disordered breathing and chronic opioid therapy.

OBJECTIVE: To assess the relation between medications prescribed for chronic pain and sleep apnea. DESIGN: An observational study of chronic pain patients on opioid therapy who received overnight polysomnographies. Generalized linear models determined whether a dose relation exists between methadone, nonmethadone opioids, and benzodiazepines and the indices measuring sleep apnea. SETTING: A private clinic specializing in the treatment of chronic pain. PATIENTS: Polysomnography was sought for all consecutive (392) patients on around-the-clock opioid therapy for at least 6 months with a stable dose for at least 4 weeks. Of these, 147 polysomnographies were completed (189 patients declined, 56 were directed to other sleep laboratories by insurance companies, and data were incomplete for seven patients). Available data were analyzed on 140 patients. OUTCOME MEASURES: The apnea-hypopnea index to assess overall severity of sleep apnea and the central apnea index to assess central sleep apnea. RESULTS: The apnea-hypopnea index was abnormal (> or =5 per hour) in 75% of patients (39% had obstructive sleep apnea, 4% had sleep apnea of indeterminate type, 24% had central sleep apnea, and 8% had both central and obstructive sleep apnea); 25% had no sleep apnea. We found a direct relation between the apnea-hypopnea index and the daily dosage of methadone (P = 0.002) but not to other around-the-clock opioids. We found a direct relation between the central apnea index and the daily dosage of methadone (P = 0.008) and also with benzodiazepines (P = 0.004). CONCLUSIONS: Sleep-disordered breathing was common in chronic pain patients on opioids. The dose-response relation of sleep apnea to methadone and benzodiazepines calls for increased vigilance.