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.

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.

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.

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.

Aortic arch surgery: retrospective analysis of outcome and neuroprotective strategies.

OBJECTIVE: To review intra- and postoperative data regarding surgical reconstruction of the aortic arch performed at our cardiosurgical centre during the past four years, and thus to deepen understanding of neurologic morbidity and of what constitutes the most effective neuroprotection. EXPERIMENTAL DESIGN: Retrospective study. SETTING: Regional University Hospital. PATIENTS: 29 patients who underwent reconstruction of aneurysm or dissection of the aortic arch. Intervention. Surgical replacement of the diseased aorta during deep hypothermia, alone or with selective cerebral perfusion (antegrade or retrograde). MEASURES: Overall mortality rate, neurologic morbidity rate, duration of extracorporeal circulation, of hypothermic circulatory arrest or of selective cerebral perfusion. Evaluation of the importance to neurological outcome of age, modality of operation (emergency or routine), biochemical parameters (glycemia, hematocrit) and perfusion technique. Recording of postoperative time of arousal, and possible correlation with length of selective cerebral perfusion. RESULTS: We observed a mortality rate of 39% (11 deaths) and a neurologic morbidity rate of 34%. Hypothermic circulatory arrest alone did not assure valid neuroprotection (5 cases, all with severe neurologic impairment), while better results were obtained with selective cerebral perfusion, especially antegrade (14 cases, with only 7% of neurologic morbidity rate). Hyperglycemia (>250 mg%) proved to be significantly associated (p=0.002) with increased incidence of adverse neurologic outcome, and the same association was observed between emergency status and adverse neurologic outcome (p=0.002). Moreover, we found an unexpected linear correlation between time of selective cerebral perfusion and postoperative time of arousal (r=0.728, p=0.000). CONCLUSIONS: Deep hypothermic circulatory arrest with selective cerebral perfusion currently represent a valid therapeutic option for brain preservation during reconstruction of the aortic arch in adults. It is mandatory to carry out a tight control of perfusion parameters (flow, pressures and temperature gradients) and biochemical variables (avoidance of hyperglycemia and modified ultrafiltration for fluid balance).

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.

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.

[Current views on the use of vasodilators in pulmonary hypertension]. / Attuali vedute sull'impiego dei vasodilatatori nell'ipertensione polmonare.

Vasodilators represent one of the main steps for the medical treatment of pulmonary hypertension; the rationale for their use is the reversibility of the pulmonary vasoconstriction, to be tested with a correct pharmacological trial. In this report the authors consider the use of calcium-channel blockers, prostaglandin and nitric oxide. Calcium blockers, the only drugs active when administered orally, provide a satisfactory clinical response in 25-30% of treated patients. Prostaglandins are active in a higher percentage of patients and can be infused in a domiciliary regimen with portable pumps even for long periods of time. Nitric oxide is the only selective pulmonary vasodilator; it is used in paediatric and adult cardiac surgery and in patients affected by respiratory distress syndrome, but its use is restricted to intensive care units and many cautions must be adopted. Finally some future therapeutic strategies are briefly reviewed: endothelin inhibitors, cGMP phosphodiesterase inhibitors etc.

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.

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.

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.

[Human error in the anesthesiological field. Up to what point is it possible to speak of prevention?]. / L'errore umano in campo anestesiologico. Fino a che punto e possibile parlare di prevenzione?

Human error (the act of judging true what is false and false what is true) has ever played and plays a significant role in the occurrence of incidents during anaesthesia. Purpose of the study. The Authors wanted to study how the different Authors analyzed the problem and to outline indications for preventive measures. Materials and methods. For this purpose we have selected papers and their references published on Journals indexed on Index. Medicus (1966-1996). The key words have been: anaesthesia or anesthesia, human error, incident and critical incident. We analyzed papers where human error in anaesthesia as a source of accidents was the main topic. The problem is analyzed starting from a classification of different errors and quantified with proper cognitive methods. Finally preventive measures are proposed. Results, Contribution of human error to the occurrence of accidents in anaesthesia ranges from 37% to 87% according to different. Authors employed techniques and sample size. Proper corrective measures on human, instrumental and environmental factors can lead to increased prevention. Conclusions. Human error exists now and will ever exist. Its gravity depends on its consequences and on preventive measures adopted.

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 myocardial ischaemia-reperfusion on granulocyte elastase release.

During extracorporeal circulation, activation and degranulation of neutrophil granulocytes occur, with subsequent massive release of elastase, a neutral protease stored in the azurophil granules. Neutrophil granulocytes and oxygen-derived free radicals are intimately involved in the occurrence of reperfusion injury, which affects especially the lungs and the myocardium. In this study we evaluated changes in the leucocyte count and of the plasma elastase levels in the coronary circulation during open heart surgery. We collected blood samples from the radial artery and the coronary sinus before skin incision, after onset of cardiopulmonary bypass and 5, 15, 30, 60, 120 minutes after the release of the aortic cross-clamp. The leucocyte count did not change significantly during the operation and no difference in leucocyte count was found between the radial artery and the coronary sinus. Plasma elastase levels significantly increased after the onset of cardiopulmonary bypass (P = 0.007) and after the release of the aortic cross-clamp (P = 0.001). Moreover, significantly higher values were found in the coronary sinus than in the radial artery 5 (P = 0.04), 15 (P = 0.02) and 30 (P = 0.02) minutes after the release of the aortic cross-clamp. We assume, therefore, that during the early phase of reperfusion, degranulation of neutrophil granulocytes occurs in the coronary circulation.