Clusters of individuals recovering from an exacerbation of chronic obstructive pulmonary disease and response to in-hospital pulmonary rehabilitation.

INTRODUCTION AND OBJECTIVES: Due to the present low availability of pulmonary rehabilitation (PR) for individuals recovering from a COPD exacerbation (ECOPD), we need admission priority criteria. We tested the hypothesis that these individuals might be clustered according to baseline characteristics to identify subpopulations with different responses to PR. METHODS: Multicentric retrospective analysis of individuals undergone in-hospital PR. Baseline characteristics and outcome measures (six-minute walking test - 6MWT, Medical Research Council scale for dyspnoea -MRC, COPD assessment test -CAT) were used for clustering analysis. RESULTS: Data analysis of 1159 individuals showed that after program, the proportion of individuals reaching the minimal clinically important difference (MCID) was 85.0%, 86.3%, and 65.6% for CAT, MRC, and 6MWT respectively. Three clusters were found (C1-severe: 10.9%; C2-intermediate: 74.4%; C3-mild: 14.7% of cases respectively). Cluster C1-severe showed the worst conditions with the largest post PR improvements in outcome measures; C3-mild showed the least severe baseline conditions, but the smallest improvements. The proportion of participants reaching the MCID in ALL three outcome measures was significantly different among clusters, with C1-severe having the highest proportion of full success (69.0%) as compared to C2-intermediate (48.3%) and C3-mild (37.4%). Participants in C2-intermediate and C1-severe had 1.7- and 4.6-fold increases in the probability to reach the MCID in all three outcomes as compared to those in C3-mild (OR = 1.72, 95% confidence interval [95% CI] = 1.2 - 2.49, p = 0.0035 and OR = 4.57, 95% CI = 2.68 - 7.91, p < 0.0001 respectively). CONCLUSIONS: Clustering analysis can identify subpopulations of individuals recovering from ECOPD associated with different responses to PR. Our results may help in defining priority criteria based on the probability of success of PR.

Fungemia due to Saprochaete capitata in a non-neutropenic patient hospitalized in an intensive care unit after cardiac surgery.

The majority of invasive fungal infections observed in non-neutropenic patients hospitalized in an intensive care unit are caused by Candida spp and current guidelines recommend echinocandins as the first-line treatment. Fungemias caused by filamentous or arthrosporic fungi such as Saprochaete capitata (previously named Geotrichum capitatum) are extremely rare. In fact, invasive infections due to S. capitata have been reported almost exclusively in neutropenic oncohematological patients. In this report, we describe a case of fungemia caused by S. capitata in a non-neutropenic patient hospitalized in an intensive care unit after aortic valve replacement. The prompt identification of S. capitata is extremely important because of its intrinsic resistance to echinocandins.

Changes of swallowing function after tracheostomy: a videofluoroscopy study.

BACKGROUND: Patients after tracheostomy often present swallowing dysfunctions but little is known about the mechanism underlying dysphagia and its reversibility. The aims of this study were: 1) to characterize swallowing dysfunctions in patients with dysphagia and tracheostomy; 2) to evaluate the reversibility of these changes; 3) to evaluate the possible influence of the underlying disease. METHODS: Prospective, observational, single-center study enrolling patients with tracheostomy admitted to a rehabilitation center over a period of 36 months. All patients who were found to be dysphagic underwent a swallowing study with videofluoroscopy (VF) at the beginning of hospital stay and a second VF study was repeated after approximately 4 weeks. RESULTS: A total of 557 patients with tracheostomy were admitted to the rehabilitation center during the considered period. 187 patients fulfilled the enrolling criteria and were studied with VF soon after admission. They had been tracheostomized for respiratory failure secondary to cerebrovascular accident (N.=106) or to acute-on chronic respiratory failure (N.=81). Incomplete backward epiglottis folding, pharyngeal retention, penetration and aspiration were the most frequent swallowing dysfunctions, observed with a frequency of 48%, 32%, 33% and 28%, respectively. Eighty-one patients underwent a second VF study, where these four swallowing phases again turned out to be the most compromised, with a frequency of 41%, 19%, 27% and 17%, respectively. The improvement was less evident in patients with chronic respiratory disease. CONCLUSION: The swallowing function is impaired in patients with dysphagia and tracheostomy, but most swallowing abnormalities appear to be partially reversible. Patients with chronic respiratory disease exhibit a worse swallowing function.

Physiological changes during low- and high-intensity noninvasive ventilation.

In a physiological randomised cross-over study performed in stable hypercapnic chronic obstructive disease patients, we assessed the short-term effects of two settings of noninvasive ventilation. One setting was aimed at maximally reducing arterial carbon dioxide tension (P(a,CO(2))) (high-intensity (Hi) noninvasive positive pressure ventilation (NPPV)): mean ± SD 27.6 ± 2.1 cmH(2)O of inspiratory positive airway pressure, 4 ± 0 cmH(2)O of expiratory positive airway pressure and respiratory rate of 22 breaths · min(-1). The other was performed according to the usual parameters used in earlier studies (low-intensity (Li)-NPPV): 17.7 ± 1.6 cmH(2)O of inspiratory positive airway pressure, 4 ± 0 cmH(2)O of expiratory positive airway pressure and respiratory rate of 12 breaths · min(-1). Both modes of ventilation significantly improved gas exchange compared with spontaneous breathing (SB), but to a greater extent using Hi-NPPV (P(a,CO(2)) 59.3 ± 7.5, 55.2 ± 6.9 and 49.4 ± 7.8 mmHg for SB, Li-NPPV and Hi-NPPV, respectively). Similarly, Hi-NPPV induced a greater reduction in the pressure-time product of the diaphragm per minute from 323 ± 149 cmH(2)O · s · min(-1) during SB to 132 ± 139 cmH(2)O · s · min(-1) during Li-NPPV and 40 ± 69 cmH(2)O · s · min(-1) during Hi-NPPV, while in nine out of 15 patients, it completely abolished SB activity. Hi-NPPV also induced a marked reduction in cardiac output (CO) measured noninvasively with a Finometer PRO (Finapres Medical Systems BV, Amsterdam, the Netherlands) compared with Li-NPPV. We conclude that while Hi-NPPV is more effective than Li-NPPV in improving gas exchange and in reducing inspiratory effort, it induces a marked reduction in CO, which needs to be considered when Hi-NPPV is applied to patients with pre-existing cardiac disease.

Last 3 months of life in home-ventilated patients: the family perception.

We studied the family's perception of care in patients under home mechanical ventilation during the last 3 months of life. In 11 respiratory units, we submitted a 35-item questionnaire to relatives of 168 deceased patients exploring six domains: symptoms, awareness of disease, family burden, dying, medical and technical problems. Response rate was 98.8%. The majority of patients complained respiratory symptoms and were aware of the severity and prognosis of the disease. Family burden was high especially in relation to money need. During hospitalisation, 74.4% of patients were admitted to the intensive care unit (ICU). 78 patients died at home, 70 patients in a medical ward and 20 in ICU. 27% of patients received resuscitation manoeuvres. Hospitalisations and family economical burden were unrelated to diagnosis and mechanical ventilation. Families of the patients did not report major technical problems on the use of ventilators. In comparison with mechanical invasively ventilated patients, noninvasively ventilated patients were more aware of prognosis, used more respiratory drugs, changed ventilation time more frequently and died less frequently when under mechanical ventilation. We have presented good points and bad points regarding end-of-life care in home mechanically ventilated patients. Noninvasive ventilation use and diagnosis have impact on this burden.

Comparison of two humidification systems for long-term noninvasive mechanical ventilation.

There is no consensus concerning the best system of humidification during long-term noninvasive mechanical ventilation (NIMV). In a technical pilot randomised crossover 12-month study, 16 patients with stable chronic hypercapnic respiratory failure received either heated humidification or heat and moisture exchanger. Compliance with long-term NIMV, airway symptoms, side-effects and number of severe acute pulmonary exacerbations requiring hospitalisation were recorded. Two patients died. Intention-to-treat statistical analysis was performed on 14 patients. No significant differences were observed in compliance with long-term NIMV, but 10 out of 14 patients decided to continue long-term NIMV with heated humidification at the end of the trial. The incidence of side-effects, except for dry throat (significantly more often present using heat and moisture exchanger), hospitalisations and pneumonia were not significantly different. In the present pilot study, the use heated humidification and heat and moisture exchanger showed similar tolerance and side-effects, but a higher number of patients decided to continue long-term noninvasive mechanical ventilation with heated humidification. Further larger studies are required in order to confirm these findings.

Maximal inspiratory and expiratory pressure measurement in tracheotomised patients.

The present study compared four different sites and conditions for the measurement of maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) in 38 spontaneous breathing tracheotomised patients. Of the patients, 28 had chronic obstructive pulmonary disease (COPD). The four different conditions were: 1) through a cuff inflated cannula (condition A); 2) through the mouth with a deflated cannula (condition B); 3) through the mouth with a phonetic uncuffed cannula (condition C); and 4) through the mouth after stoma closure (condition D). Five trials in each condition were performed using a standardised method. The measurement of both MIP and MEP differed significantly depending on the condition of measurement. MIP taken in condition A was significantly higher when compared with conditions B, C and D. MEP in condition A was significantly higher when compared with condition B and D. In condition A the highest frequency of the best measurement of MIP and MEP was observed at the fourth and fifth effort, respectively. The same results were obtained after the selection of only COPD patients. In conclusion, respiratory muscle assessment differs significantly depending on measurement condition. Measurement through inflated cannula tracheotomy yields higher values of both maximal inspiratory and maximal expiratory pressure.

Effect of varying the pressurisation rate during noninvasive pressure support ventilation.

The aim of the study was to assess the effects of varying the pressurisation rate during noninvasive pressure support ventilation on patients' breathing pattern, inspiratory effort, arterial blood gases, tolerance to ventilation and amount of air leakage. A total of 15 chronic obstructive pulmonary disease patients recovering from an acute episode of hypercapnic acute respiratory failure were studied during four randomised trials with different levels of pressurisation rate. No significant changes were observed in breathing pattern and arterial blood gases between the different runs. The pressure time product of the diaphragm, an estimate of its metabolic consumption, was significantly lower with all pressurisation rates than with spontaneous breathing, but was significantly lowest with the fastest rate. However, air leak, assessed by the ratio between expired and inspired tidal volumes, increased and the patients' tolerance of ventilation, measured using a standardised scale, was significantly poorer with the fastest pressurisation rate. In chronic obstructive pulmonary disease patients recovering from an episode of acute hypercapnic respiratory failure and ventilated with noninvasive pressure support ventilation, different pressurisation rates resulted in different reductions in the pressure time product of the diaphragm; this reduction was greater with the fastest rate, but was accompanied by significant air leaks and poor tolerance.

Use of bronchodilators during non-invasive mechanical ventilation.

Bronchodilators represent one of the most important therapeutic weapons for the treatment of airway obstructive diseases and the inhaled route of administration is very often employed due to the greater drug availability and reduced magnitude of side effects. During acute exhacerbations, it is not unfrequent that the elastic and resistive loads imposed on the ventilatory pump overcome the force sustainable by the respiratory muscles and the patient requires ventilatory assistance, in order to relieve fatigue and to optimize alveolar gas exchange. During these episodes, inhaled bronchodilators, far from being discontinued, sometime must be administered during mechanical ventilation, that, in hypercapnic ventilatory failure can be frequently applied noninvasively with a good rate of success. While in the current literature there are a lot of data about inhaled drug administration during invasive mechanical ventilation, very few data are available on the topic of aerosol therapy during noninvasive mechanical ventilation. With the present paper we want to analyze the rationale, the feasibility and the current data dealing with the administration of inhaled drugs during noninvasive mechanical ventilation.

Influence of underlying lung disease on early postoperative course after single lung transplantation.

BACKGROUND: Single lung transplantation can be a suitable therapeutic option for a wide range of end-stage lung diseases: pulmonary fibrosis, emphysema, primary pulmonary hypertension and Eisenmenger's syndrome. Yet, patients suffering from different diseases have significantly different cardiovascular and respiratory functional profiles that can exert a profound influence on their response to the perioperative procedures. Our purpose is to analyze whether the patient's underlying disease can influence the early postoperative outcome after single lung transplantation. METHODS: We carried out a retrospective analysis on perioperative charts of patients undergoing single lung transplantation during an 8-year period. We focused our attention on the following data: underlying lung disease, age, sex, baseline cardiorespiratory data (pulmonary artery pressure, cardiac index, forced expired volume, vital capacity, arterial blood gases, body mass index), intraoperative data (duration of graft ischemia, use of cardiopulmonary bypass) and indexes of adverse postoperative outcome (in-hospital death, mechanical ventilatory support >7 days). Patients were gathered in 3 groups (restrictive, obstructive and vascular) according to the kind of disease and functional data and the association between disease and outcome was assessed by means of logistic regression analysis. Moreover, we evaluated whether any of the patient's functional parameters could be considered predictive of adverse postoperative outcome. RESULTS: We observed a weak association between restrictive disease and adverse postoperative outcome while, on the other hand, obstructive and vascular forms showed a close association with an adverse outcome, with a borderline statistical significance. Among all the considered variables, only intraoperative use of CPB turned out to be predictive of adverse outcome, while other variables simply indicated a trend towards a better outcome. CONCLUSIONS: Patients with vascular and obstructive diseases have the worst postoperative course, with a higher in-hospital mortality rate and longer duration of ventilation; in particular, the perioperative course of vascular patients is heavily influenced by the intraoperative use of cardiopulmonary bypass.

Respiratory muscles in chronic obstructive pulmonary disease and asthma.

Chronic obstructive pulmonary disease (COPD) and asthma are characterized by airflow obstruction and significant increase of respiratory muscle workload, with concrete risk of ventilatory pump failure. Respiratory muscles, the main component of this pump, undergo structural and functional changes during the course of these diseases. Aim of the present paper is to analyze modifications of respiratory muscles in COPD and asthma. An analysis of the most important controlled clinical studies released during the past years was carried out. The patients suffered from chronic obstructive pulmonary disease and asthma. In COPD, respiratory muscles have to cope with an increased load, an intrinsic weakness and a mechanical disadvantage, especially in the diaphragmatic length-force relationship; in patients with acute asthma, the main features are a massive hyperinflation and a persistent inspiratory muscle activity during expiration. Modifications of respiratory muscles deserve great consideration not only for the complete comprehension of the underlying physiopathologic aspects of these diseases, but also for the optimal clinical management: a reduced pulmonary hyperinflation in COPD place the respiratory muscles in a better position of the force-length curve while great care must be payed to the metabolic and nutritional aspects. During asthmatic crisis respiratory muscles are subjected to a sort of intense training but anyway persistence of bronchospasm in most severe attacks can lead to exhaustion of the ventilatory pump and need of mechanical ventilatory support.

[Single lung transplantation retrospective analysis of intraoperative cardiovascular problems]. / Trapianto di polmone singolo. Analisi retrospettiva delle problematiche cardiovascolari intraoperatorie.

BACKGROUND: Analysis of haemodynamic problems during single-lung transplantation and of methodologies employed for their treatment. DESIGN OF THE STUDY: clinical retrospective study. SETTING: General University Hospital. PATIENTS: patients with irreversible lung disease, either parenchymal or vascular, undergoing single lung transplantation. INTERVENTIONS: recording of circulatory failure episodes and treatment with pharmacologic support or cardiopulmonary bypass. Modifications occurring during the study period with respect to drugs administered. Evaluation of the consequences of cardiopulmonary bypass on the postoperative outcome, namely on the duration of mechanical ventilation and length of stay in the intensive care unit. RESULTS: During the last 9 years 69 single-lung transplantations have been performed. In 50% of cases a pharmacologic support has been employed; the drug association dobutamine/nitroprusside has been gradually replaced by the association norepinephrine/nitric oxide for the treatment of right ventricular failure. Twenty patients required cardiopulmonary bypass and this caused a significant increase of the duration of mechanical ventilation and length of stay in the intensive care unit. CONCLUSIONS: Hemodynamic changes during lung transplantation are complex and often severe, leading to a clinical status of right ventricular failure, that sometime requires a mechanical circulatory support. The introduction of nitric oxide in clinical practice significantly contributed to the optimization of intraoperative cardiocirculatory profile of patients, leading to a reduction in the use of vasoactive drugs and cardiopulmonary bypass.

Monitoring aspects during port-access cardiac surgery.

OBJECTIVE: To report the experience gained at our Cardiosurgical Centre with the recently introduced port-access technique. EXPERIMENTAL DESIGN: Prospective collection of data from the month of October 1997. SETTING: Regional University HospitaL Patients: Adult patients undergoing coronary bypass graft or mitral valve surgery. INTERVENTIONS: Port-access technique makes it possible to carry out open-heart procedures through a minithoracotomy and extrathoracic cardiopulmonary bypass with a set of properly designed catheters (Heartport EndoCPB system) for cardioplegia delivery and heart venting. MEASURES: Transesophageal echography and pressure traces are the main monitoring tools used for the correct placement of these catheters and for the clinical management of the patient. RESULTS: Sixty-two cases have been performed so far. A complete description of the procedure, with monitoring aspects and problems encountered is thoroughly presented. CONCLUSIONS: The major differences with traditional cardiac surgery are that interruption of myocardial perfusion is not achieved through a transversal clamp but through an endovascular occlusive balloon and that thoracic access is by minithoracotomy. Unlike traditional open surgery, the surgeon has no direct vision of the position of the clamp and the anesthesiologist can not visually inspect the contractile state of the heart. The operative team has to cope with a multifaceted system of monitored variables that must be continuously integrated and interpreted. Tight cooperation and continuous communication between anaesthesiologist, surgeons and perfusionist appear to be more important than in any other cardiac operation.

Case reports in anesthesiology: their trend through 17 years.

UNLABELLED: The study objective was to delineate the trend of case reports (the simplest of the descriptive forms of study) in the anesthesiological literature by analyzing the frequency of publication, and citation, and especially of the place of citation of a sample of published case reports. It is our opinion that case report in anesthesia is particularly suitable for this specialty rather than for others and is often the first signal of a complication, an adverse event, an anesthetic problem in rare disease and alerts other anesthesiologists to the possibility of unexpected events. METHODS: We analyzed the case reports published on an Anesthesiological journal placed in the middle in term of Impact Factor, from January 1980 to December 1997. Citations of each case report were obtained using computer searches of the Science Citation Index (SCI). For each of these case reports we collected in a custom-designed data base the following data: year of publication, number of authors, number of citations per year, place of citation, type of article quoting the case report, number of self-citations, year of first citation. MAIN RESULTS: We identified 637 case reports and 1946 citations. The number of case reports increased through the years up to a peak in 1994-95 and the same trend was observed for citations and self-citations, the number of authors per case report was < or = 4 in 90.4%; 74.2% of total case reports cited were first cited within two years of publication, while 34.7% were never cited. The type of article quoting the case reports has been, in the majority of cases, an original article. CONCLUSIONS: The analysed case reports and the number of citations can give us information about the importance of a clinical situation at a particular time.

Port access cardiac surgery.

The port-access technique for cardiac surgery was recently developed at Stanford University in California as a less invasive method to perform some cardiac operations. The port-access system has been described in detail elsewhere. It is based on femoral arterial and venous access for cardiopulmonary bypass (CPB) and on the adoption of a specially designed triple-lumen catheter described originally by Peters, and subsequently modified and developed in the definitive configuration called the endoaortic clamp.

Natural killer cell activity and delivery: possible influence of cortisol and anesthetic agents. A study on newborn cord blood.

The aim of this study was to evaluate the influence of the method of delivery, the level of cord blood lidocaine, and the cortisol concentration on the cord blood natural killer (NK) activity in the full-term healthy newborn. We studied healthy newborns delivered by elective cesarean section without labor under general anesthesia (n = 24), delivered by cesarean section under epidural anesthesia (n = 21), and delivered vaginally with uncomplicated labor (n = 19). The NK cell activity was significantly lower in newborns delivered by cesarean section under epidural anesthesia than it was in the general anesthesia group, while it was similar to the levels found in vaginally delivered newborns. The cortisol concentration was highest in the vaginal delivery group (589.2 +/- 200 mmol/l) and lowest in the general anesthesia group (199.2 +/- 81.9 mmol/l). The mean serum lidocaine concentration was 414.1 +/- 370 microgram/l in the epidural anesthesia group and undetectable in the other groups. In conclusion, our data suggest that the cord blood NK activity was significantly influenced by the method of delivery. This effect could be related to anesthetics given to the mother for general or epidural anesthesia or to the endocrine-metabolic variations observed after different degrees of delivery-related stress. The NK cells being a first-line defense mechanism against viral infections, the results of this study suggest an association with the occurrence of early perinatal infections, especially in preterm infants.

Unexpected finding of barium sulphate on the surface of a microspinal catheter.

During a study with a scanning electron microscope to evaluate the structure of microspinal catheter after its removal from subarachnoid space, we found an unusual case. The observation with the microscope of the tip of a catheter removed at the end of an operation for hip replacement in a old female showed the presence of grounded particles with a crystal shape covering the outer surface. Further analysis of this material with an Energy-Dispersive Spectrometer (EDS) showed that it was barium. The patient performed a large bowel barium enema 8 months earlier for a painful syndrome to the lower abdomen. Authors rule out the contamination from the skin and suggest two possible mechanisms of passage of barium from blood to cerebrospinal fluid (CSF) and so to the surface of the catheter.