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E Clini

Publications and source records attributed to E Clini.

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

The appropriate setting of noninvasive pressure support ventilation in stable COPD patients.

STUDY OBJECTIVE: To evaluate the short-term physiologic effects of two settings of nasal pressure-support ventilation (NPSV) in stable COPD patients with chronic hypercapnia. DESIGN: Randomized controlled physiologic study. SETTING: Lung function units and outpatient clinic of two affiliated pulmonary rehabilitation centers. PATIENTS: Twenty-three patients receiving domiciliary nocturnal NPSV for a mean (+/- SD) duration of 31 +/- 20 months. METHODS: Evaluation of arterial blood gases, breathing pattern, respiratory muscles, and dynamic intrinsic positive end-expiratory pressure (PEEPi,dyn) during both unassisted and assisted ventilation. Two settings of NPSV were randomly applied for 30 min each: (1) usual setting (U), the setting of NPSV actually used by the individual patient at home; and (2) physiologic setting (PHY), the level of inspiratory pressure support (IPS) and external positive end-expiratory pressure (PEEPe) tailored to patient according to invasive evaluation of respiratory muscular function and mechanics. RESULTS: All patients tolerated NPSV well throughout the procedure. Mean U was IPS, 16 +/- 3 cm H(2)O and PEEPe, 3.6 +/- 1.4 cm H(2)O; mean PHY was IPS, 15 +/- 3 cm H(2)O and PEEPe, 3.1 +/- 1.6 cm H(2)O. NPSV was able to significantly (p < 0.01) improve arterial blood gases independent of the setting applied. When compared with spontaneous breathing, both settings induced a significant increase in minute ventilation (p < 0.01). Both settings were able to reduce the diaphragmatic pressure-time product, but the reduction was significantly greater with PHY (by 64%; p < 0.01) than with U (56%; p < 0.05). Eleven of 23 patients (48%) with U and 7 of 23 patients (30%) with PHY showed ineffective efforts (IE); the prevalence of IE (20 +/- 39% vs 6 +/- 11% of their respiratory rate with U and PHY, respectively) was statistically different (p < 0.05). CONCLUSION: In COPD patients with chronic hypercapnia, NPSV is effective in improving arterial blood gases and in unloading inspiratory muscles independent of whether it is set on the basis of patient comfort and improvement in arterial blood gases or tailored to a patient's respiratory muscle effort and mechanics. However, setting of inspiratory assistance and PEEPe by the invasive evaluation of lung mechanics and respiratory muscle function may result in reduction in ineffective inspiratory efforts. These short-term results must be confirmed in the long-term clinical setting.

Aged↗
PubMed1999

High-dose heparin impairs nitric oxide pathway and vasomotion in rats.

BACKGROUND: Platelet-activating effects have been reported with high-dose heparin in acute thrombotic disorders. Recent studies have shown that increased platelet aggregation is due to reduced nitric oxide (NO) production in endothelial cells cultured in the presence of high-dose heparin. The aim of this study was to determine whether heparin can affect the NO pathway and the regulation of the vascular tone in vivo. METHODS AND RESULTS: Anesthetized and mechanically ventilated Sprague-Dawley rats were treated with high-dose heparin. After 4 hours, the endothelial constitutive NO synthase (ecNOS) protein content in the aorta decreased (36% reduction, P<0.05), as detected by immunoblotting, and NO-dependent vascular reactivity was impaired. In fact, the increase in mean arterial blood pressure after inhibition of ecNOS with NG-nitro-L-arginine methyl ester (30 mg/kg) was smaller in heparin-treated animals than in controls (+26. 9+/-4.8 versus +48.3+/-9.1 mm Hg, P<0.05), and further infusion of the biological ecNOS substrate L-arginine (0.5 g/kg) was ineffective in reversing systemic vasoconstriction (-1% versus 28% vasodilatation, P<0.001). CONCLUSIONS: High-dose heparin can significantly affect vascular reactivity in vivo by downregulation of ecNOS protein expression.

Animals↗
PubMed1999

Detection of nitric oxide in exhaled air of different animal species using a clinical chemiluminescence analyser.

The aim of the present study was to evaluate the nitric oxide (NO) concentrations present in end-expired gas (FENO) of different animal species under basal and stimulated conditions using a clinical chemiluminescence analyser, which has been developed for measurement of single exhalations in humans. Anaesthetised, tracheotomised and artificially ventilated guinea pigs, rats and rabbits were prepared for recording systemic blood pressure and FENO. Stable levels of FENO were detected in expired air over a 1-h observation period in the three animal species tested. Rabbits exhibited the highest concentrations and output (FENO 12.9+/-1.0 ppb, VNO 9.0+/-0.7 nl min-1), followed by guinea pigs (FENO 6.2+/-0.70 ppb, VNO 1.7+/-0.19 nl min-1) and rats (FENO 0.9+/-0.01 ppb, VNO 0.25+/-0.00 nl min-1). L-arginine (1 g kg-1 i.v.) evoked significant increments in VNO in guinea pigs and rabbits but was ineffective in rats. However, L-arginine showed a direct effect on blood pressure in all the animal species tested, causing a rapid fall in the mean arterial blood pressure (MABP; 38, 48 and 50% decrease in rabbits, guinea pigs and rats, respectively; P<0.05). An inhibitor of endogenous NO synthesis, NG-nitro-L-arginine methyl ester (L-NAME, 20 mg kg-1 i.v.), decreased both basal and L-arginine-induced VNO in guinea pigs and rabbits, but was ineffective in rats. L-NAME increased MABP in all the animal species tested (58% in guinea pigs, 43% in rats and 18% in rabbits; P<0.05). The results indicate that it is possible to detect NO in the exhaled air of different animal species using a clinical chemiluminescence analyser and that different species exhibit striking differences in the levels of basal and stimulated NO output.

Animals↗
PubMed1999

Physiological effects of posture on mask ventilation in awake stable chronic hypercapnic COPD patients.

Stable chronic hypercapnic patients are often prescribed long-term mask noninvasive pressure support ventilation (NPSV). There is a lack of information on the effects of posture on NPSV. Therefore posture induced changes in physiological effects of NPSV in awake stable chronic hypercapnic patients were evaluated. In 12 awake chronic obstructive pulmonary disease (COPD) patients breathing pattern, respiratory muscles, mechanics and dyspnoea (by visual analogue scale: VAS) were evaluated during spontaneous breathing (SB) in sitting posture and during NPSV in sitting, supine and lateral positions randomly assigned. Arterial blood gases were evaluated during SB and at the end of the last NPSV session (whatever the posture). As expected NPSV resulted in a significant improvement in carbon dioxide tension in arterial blood (Pa,CO2) (from 7.4+/-0.85 to 6.9+/-0.7 kPa). When compared with SB, sitting NPSV resulted in a significant increase in tidal volume and minute ventilation and in a significant decrease in breathing frequency. Inspiratory muscle effort as assessed by oesophageal pressure swings and pressure-time product per minute (from 14+/-4.8 to 6.2+/-3.5 cmH2O, and from 240+/-81 to 96+/-60 cmH2O x s x min(-1) respectively), intrinsic dynamic positive end expiratory pressure (from 2.7+/-2.3 to 1.4+/-1.3 cmH2O) and expiratory airway resistance (from 18+/-7 to 5+/-3 cmH2O x L x s(-1)) decreased during sitting NPSV, whereas VAS did not change. Changing posture did not significantly affect any parameter independently of the patients weight, whether obese or not. In awake stable hypercapnic chronic obstructive pulmonary disease patients changing posture does not significantly influence breathing pattern and respiratory muscles during noninvasive pressure support ventilation suggesting that mask ventilation may be performed in different positions without any relevant difference in its effectiveness.

Aged↗
PubMed1999

Differences in spontaneous breathing pattern and mechanics in patients with severe COPD recovering from acute exacerbation.

The aims of this study were to assess spontaneous breathing patterns in patients with chronic obstructive pulmonary disease (COPD) recovering from acute exacerbation and to assess the relationship between different breathing patterns and clinical and functional parameters of respiratory impairment. Thirty-four COPD patients underwent assessment of lung function tests, arterial blood gases, haemodynamics, breathing pattern (respiratory frequency (fR), tidal volume (VT), inspiratory and expiratory time (tI and tE), duty cycle (tI/ttot), VT/tI) and mechanics (oesophageal pressure (Poes), work of breathing (WOB), pressure-time product and index, and dynamic intrinsic positive end-expiratory pressure (PEEPi,dyn)). According to the presence (group 1) or absence (group 2) of Poes swings during the expiratory phase (premature inspiration), 20 (59%) patients were included in group 1 and 14 (41%) in group 2. Premature inspirations were observed 4.5+/-6.4 times x min(-1) (range 1-31), i.e. 20+/-21% (3.7-100%) of total fR calculated from VT tracings. In group 1 the coefficient of variation in VT, tE, tI/ttot, PEEPi,dyn, Poes and WOB of the eight consecutive breaths immediately preceding the premature inspiration was greater than that of eight consecutive breaths in group 2. There were no significant differences in the assessed parameters between the two groups in the overall population, whereas patients with chronic hypoxaemia in group 1 showed a more severe impairment in clinical conditions, mechanics and lung function than hypoxaemic patients in group 2. In spontaneously breathing patients with chronic obstructive pulmonary disease recovering from an acute exacerbation, detectable activity of inspiratory muscles during expiration was found in more than half of the cases. This phenomenon was not associated with any significant differences in anthropometric, demographic, physiological or clinical characteristics.

Acute Disease↗
PubMed1998

Noninvasive mechanical ventilation in the weaning of patients with respiratory failure due to chronic obstructive pulmonary disease. A randomized, controlled trial.

BACKGROUND: In patients with acute exacerbations of chronic obstructive pulmonary disease, mechanical ventilation is often needed. The rate of weaning failure is high in these patients, and prolonged mechanical ventilation increases intubation-associated complications. OBJECTIVE: To determine whether noninvasive ventilation improves the outcome of weaning from invasive mechanical ventilation. DESIGN: Multicenter, randomized trial. SETTING: Three respiratory intensive care units. PATIENTS: Intubated patients with chronic obstructive pulmonary disease and acute hypercapnic respiratory failure. INTERVENTION: A T-piece weaning trial was attempted 48 hours after intubation. If this failed, two methods of weaning were compared: 1) extubation and application of noninvasive pressure support ventilation by face mask and 2) invasive pressure support ventilation by an endotracheal tube. MEASUREMENTS: Arterial blood gases, duration of mechanical ventilation, time in the intensive care unit, occurrence of nosocomial pneumonia, and survival at 60 days. RESULTS: At admission, all patients had severe hypercapnic respiratory failure (mean pH, 7.18+/-0.06; mean PaCO2, 94.2+/-24.2 mm Hg), sensory impairment, and similar clinical characteristics. At 60 days, 22 of 25 patients (88%) who were ventilated noninvasively were successfully weaned compared with 17 of 25 patients (68%) who were ventilated invasively. The mean duration of mechanical ventilation was 16.6+/-11.8 days for the invasive ventilation group and 10.2+/-6.8 days for the noninvasive ventilation group (P = 0.021). Among patients who received noninvasive ventilation, the probability of survival and weaning during ventilation was higher (P = 0.002) and time in the intensive care unit was shorter (15.1+/-5.4 days compared with 24.0+/-13.7 days for patients who received invasive ventilation; P = 0.005). Survival rates at 60 days differed (92% for patients who received noninvasive ventilation and 72% for patients who received invasive ventilation; P = 0.009). None of the patients weaned noninvasively developed nosocomial pneumonia, whereas 7 patients weaned invasively did. CONCLUSIONS: Noninvasive pressure support ventilation during weaning reduces weaning time, shortens the time in the intensive care unit, decreases the incidence of nosocomial pneumonia, and improves 60-day survival rates.

Aged↗
PubMed1998

Outcome of COPD patients performing nocturnal non-invasive mechanical ventilation.

The role of non-invasive nocturnal domiciliary ventilation (NNV) in chronic obstructive pulmonary disease (COPD) patients with chronic hypercapnia is still discussed. The aims of this study were to evaluate the long-term survival, the clinical effectiveness and side-effects of NNV in these patients. Forty-nine stable hypercapnic COPD patients on long-term oxygen therapy (LTOT) were assigned to two groups: in Group 1, 28 patients performed NNV by pressure support modality in addition to LTOT; in Group 2, 21 patients continued their usual LTOT regimen. Treatment was assigned according to the compliance to NNV, after an in hospital period. Mortality rate, hospital stay (HS) and ICU admissions (IA) were recorded in the two groups. HS and IA were compared to those recorded in a similar period of follow-back. Lung and respiratory muscle function, dyspnoea, and exercise capacity (by 6-min walk test) were evaluated baseline and every 3-6 months up to 3 yr. Mean follow-up time was 35 +/- 7 months. Mortality rate was not different between the two groups: 16, 33, 46% and 13, 28, 50% at 1, 2 and 3 yr in Groups 1 and 2 respectively. Lung and respiratory muscle function did not significantly change over time. A significant increase in 6-min walk test (from 245 +/- 78 to 250 +/- 88, 291 +/- 75, 284 +/- 89 m after 1, 2 and 3 yr respectively, P < 0.01) was observed only in patients undergoing NNV. In comparison to the follow back HS significantly decreased in both groups (from 37 +/- 29 to 15 +/- 12 and from 32 +/- 18 to 17 +/- 11 days/pt/yr in Groups 1 and 2 respectively, P < 0.001) whereas IA significantly decreased only in patients performing also NNV (from 1.0 +/- 0.7 to 0.2 +/- 0.3/pt/yr, P < 0.0001). Addition of NNV by pressure support modality to LTOT does not improve long term survival but significantly reduces ICU admissions and improves exercise capacity in severe COPD with hypercapnia.

Aged↗
PubMed1998

Endogenous nitric oxide in patients with stable COPD: correlates with severity of disease.

BACKGROUND: Increased levels of exhaled nitric oxide (eNO) have been reported in asthmatic subjects but little information is available on eNO in patients with advanced chronic obstructive pulmonary disease (COPD). A study was undertaken to evaluate the levels of eNO in patients with stable COPD of different degrees of severity. METHODS: Peak and plateau values of eNO (PNO and PLNO, respectively) were evaluated in 53 patients with COPD and analysed according to the level of forced expiratory volume in one second (FEV1) and the presence of cor pulmonale (CP) (group 1, FEV1 < 35% predicted with CP, n = 15; group 2, FEV1 < 35% predicted without CP, n = 15; group 3, FEV1 > 35% predicted, n = 23). Seventeen normal subjects served as controls. RESULTS: All the patients with COPD had reduced levels of PLNO compared with the controls (mean (SD) 6.3 (3.0) and 9.4 (2.8) ppb, respectively). In groups 1 and 2 PLNO levels were significantly lower than in subjects in group 3 (5.5 (2.9), 5.7 (3.5), and 7.1 (2.7) ppb, respectively; p < 0.01 ANOVA). In all subjects % predicted FEV1 correlated slightly with PLNO but not with PNO. CONCLUSION: Patients with severe stable COPD have reduced levels of eNO compared with normal subjects. eNO levels are slightly related to the severity of airflow obstruction.

Aged↗
PubMed1998

Acute effects of deep diaphragmatic breathing in COPD patients with chronic respiratory insufficiency.

This study investigated the impact of deep diaphragmatic breathing (DB) on blood gases, breathing pattern, pulmonary mechanics and dyspnoea in severe hypercapnic chronic obstructive pulmonary disease (COPD) patients recovering from an acute exacerbation. Transcutaneous partial pressure of carbon dioxide (Ptc,CO2) and oxygen (Ptc,O2) and arterial oxygen saturation (Sa,O2), were continuously monitored in 25 COPD patients with chronic hypercapnia, during natural breathing and DB. In eight of these patients, breathing pattern and minute ventilation (V'E) were also assessed by means of a respiratory inductance plethysmography. In five tracheostomized patients, breathing pattern and mechanics were assessed by means of a pneumotachograph/pressure transducer connected to an oesophageal balloon. Subjective rating of dyspnoea was performed by means of a visual analogue scale. In comparison to natural breathing deep DB was associated with a significant increase in Ptc,O2 and a significant decrease in Ptc,CO2, with a significant increase in tidal volume and a significant reduction in respiratory rate resulting in increased V'E. During DB, dyspnoea worsened significantly and inspiratory muscle effort increased, as demonstrated by an increase in oesophageal pressure swings, pressure-time product and work of breathing. We conclude that in severe chronic obstructive pulmonary disease patients with chronic hypercapnia, deep diaphragmatic breathing is associated with improvement of blood gases at the expense of a greater inspiratory muscle loading.

Aged↗
PubMed1998

Mechanical ventilation in chronic respiratory insufficiency: report on an Italian nationwide survey. The Italian Telethon Committee and the AIPO Study Group on Pulmonary Rehabilitation and Intensive Care.

Respiratory home care is an important aspect of rehabilitation programmes designed for patients needing long-term mechanical ventilation. Many differences have emerged between countries in the long-term care of these patients, depending on the different ways of supplying material, managing patients and providing equipment. The results of analysis of the data obtained in a preliminary survey carried out in 1995-1996 among 115 Italian centres operating in the field of home mechanical ventilation are presented. A questionnaire (all closed-circuit items) consisting of two sections (the first epidemiological, and the second methodological and economic) was sent to all centres. Fifty-seven out of 115 (50%) centres responded to the questionnaire, with a prevalence of responses from the north of Italy (37 centres). The responding centres had been working in this field for a mean period of 6 +/- 3 yrs, and a total of 1,842 patients were surveyed. The analysis focuses on the prevalence of treated diseases, methods of mechanical ventilation, regulation of prescription, evaluations carried out during follow-up, supply of equipment, costs and reimbursement, and relations with volunteer associations. A more thorough approach to all the problems emerging from this Italian survey regarding candidates for home mechanical ventilation is warranted. A more detailed comparative analysis of indications, management and costs vis-à-vis other countries should contribute towards achieving maximum uniformity of standards throughout Europe.

Chronic Disease↗
PubMed1997

Non-invasive haemodynamic effects of two nasal positive pressure ventilation modalities in stable chronic obstructive lung disease patients.

The aim of this study was to compare the haemodynamic effects of a 45-min session of two modalities of non-invasive positive pressure ventilation (nPPV), by means of cardiac echo-Doppler and right heart catheterization, in chronic obstructive lung disease (COPD) patients with chronic respiratory insufficiency. Fourteen patients with stable COPD (11 males, mean age 62.9 +/- 9.8 years) underwent right heart catheterization using a floating Grandjean catheter and simultaneous echo-Doppler measurements before and during two randomly applied 45-min ventilatory sessions, consisting of nasal intermittent positive pressure ventilation in assist/control mode (nIPPV) and nasal pressure support ventilation (nPSV). Blood gases improved significantly during both modalities of ventilation. A significant increase during ventilatory sessions was found in invasive pulmonary right atrial pressure and cardiac output. A statistically significant decrease was found in the flow velocity peak of the superior vena cava and hepatic vein, and in systodiastolic flow velocity integral of the superior vena cava and hepatic vein. The inferior vena cava collapsibility index also decreased significantly during both ventilations. Right atrium diameter and area significantly decreased while right ventricular diameter significantly increased. The echo-Doppler cardiac output decreased significantly while systolic pulmonary artery pressure increased. A short session of both nIPPV and nPSV even without PEEP can induce significant haemodynamic changes in patients with stable COPD. Two-dimensional Doppler echocardiography is a non-invasive device with sufficient reliability to monitor the haemodynamic effects of nPPV. Further studies are needed to assess the effects of nPPV on vascular peripheral flows.

Adult↗
PubMed1997

Breathing pattern and respiratory mechanics in chronically tracheostomized patients with chronic obstructive pulmonary disease breathing spontaneously through a hygroscopic condenser humidifier.

Hygroscopic condenser humidifiers (HCHs) have been proposed to artificially condition gases breathed by intubated and mechanically ventilated patients. These devices may improve viscosity and coloring of secretions, preventing further bacterial colonization, and heat inspiratory flow in chronically tracheostomized (CT) patients during spontaneous breathing. The aim of this study was to evaluate the effects of HCH on respiratory mechanics and breathing pattern in CT patients with chronic obstructive pulmonary disease (COPD) breathing spontaneously during quiet breathing and maximal voluntary ventilation (MVV). In a prospective, randomized, controlled study on 21 stable spontaneously breathing CT COPD patients, breathing pattern and respiratory mechanics were evaluated by means of a flow sensor and an esophageal pressure (Pes) catheter during quiet breathing in random order either with or without a HCH connected to the tracheostomy. Six of the patients were also studied during maximal voluntary ventilation (MVV). In comparison to without HCH, the application of HCH did not induce changes in the breathing pattern and respiratory mechanics during quiet breathing. As expected, in comparison to quiet breathing, MVV in 6 patients with HCH induced significant changes in respiratory frequency, minute ventilation, mean inspiratory flow, Pes, work of breathing, pressure time product and index. These changes were not significantly different without the application of HCH. In CT COPD patients spontaneously breathing. HCHs have no significant effects on the breathing pattern and respiratory mechanics both during quiet breathing and MVV.

Aged↗
PubMed1997

Breathing pattern and respiratory mechanics in patients with amyotrophic lateral sclerosis.

The aim of this study was to evaluate the time course of breathing pattern and respiratory mechanics in patients with amyotrophic lateral sclerosis (ALS). A study was conducted on 25 out of 38 eligible ALS patients. Neurological status, arterial blood gases (ABGs), spirometry, breathing pattern (minute ventilation (V'E), tidal volume (VT), respiratory frequency (fR), duty cycle (duration of inspiration/duration of total breathing cycle (tI/ttot)), respiratory drive (P0.1)), respiratory mechanics (oesophageal pressure (Ppl), dynamic compliance (CL,dyn), pressure time product (PTP) and index (PTI), work of breathing (WOB)), and respiratory muscle (RM) strength as assessed by maximal oesophageal pressure (Ppl,max) were evaluated at presentation (to) in all patients and after 6 months (t6) in 11 patients. At to, the mean values of the degree of neurological impairment were 60+/-20 and 103+/-30 as assessed by the Norris scale and Medical Research Council (MRC) score, respectively. From the time of the first neurological symptom, survival time ranged 7-50 months. Diurnal ABGs were normal. A mild restrictive pattern was observed, a forced vital capacity (FVC) <70% of predicted being present in 45% of patients, only FVC % pred (r=0.59; p<0.05), forced expiratory volume in one second (FEV1) % pred (r=0.53; p<0.05) and survival (r=0.64; p<0.05) showing a significant correlation with the Norris scale. A Ppl,max <30 cmH2O was associated with a significantly greater mortality, Ppl,max being correlated with survival (r=0.79, p<0.05). At t6, fR, fR/VT, P0.1/Ppl,max, were significantly increased in comparison to to, while FVC % pred, vital capacity (VC) % pred, FEV1 % pred, VT and Ppl,max were significantly reduced. These results suggest a progressive deterioration in breathing pattern and in respiratory muscle strength with progression of disease.

Aged↗
PubMed1997

Breathing pattern and arterial blood gases during Nd-YAG laser photoresection of endobronchial lesions under general anesthesia: use of negative pressure ventilation: a preliminary study.

STUDY OBJECTIVE: To evaluate the efficacy of negative pressure ventilation (NPV) in avoiding or reducing apneas and related hypoxemia and respiratory acidosis during laser therapy (LT) of endobronchial lesions. DESIGN: A prospective, controlled, randomized study. SETTING: An operating theater of a respiratory endoscopy and laser therapy unit. POPULATION AND INTERVENTION: Twenty-seven consecutive patients referred to LT were entered into the study. Fourteen patients were randomly assigned to LT under general anesthesia and spontaneous assisted ventilation (control group) whereas in 13 cases, NPV by a poncho-wrap ventilator (NPV group) was added to the procedure. MEASUREMENTS AND RESULTS: The prevalence and the duration of apnea/hypopnea periods assessed by respiratory inductive plethysmography during LT were significantly reduced under NPV, compared to the control group. As compared to baseline, during LT, all control patients developed mild to severe hypercapnia (PaCO2 ranging from 55 to 76 mm Hg) and respiratory acidosis (pH from 7.33 to 7.19), whereas only three patients undergoing NPV (23%) developed hypercapnia (PaCO2 from 52 to 68 mm Hg) and related acidosis (pH from 7.29 to 7.21). Optimal oxygenation was achieved in all of the patients; nevertheless, patients under NPV needed a lower mean oxygen supply; five of them (38%) could be treated at a fraction of inspired oxygen of 0.21 for the whole procedure. CONCLUSION: NPV may be useful in reducing apneas during laser therapy under general anesthesia, thus reducing hypercapnia, related acidosis, and need of oxygen supplementation.

Adult↗
PubMed1997

Patient ventilator interfaces: practical aspects in the chronic situation.

In the ventilator-dependent patient, the nonpsychological problems of the chronic phase relate mainly to aspects of the patient ventilator interface. Humidification, suctioning of secretions, and ventilatory circuit and monitoring are the three most important aspects to which careful attention is needed. Good humidification can be obtained by means of various devices, which can provide humidity directly or indirectly: in the tracheostomized patient, the heat and moisture exchanger appears to be a good method because of its antibacterial properties. Airway suctioning is frequently needed in patients receiving ventilation invasively. Suctioning of secretions might possibly be associated with the risk of major cardiorespiratory complications: bacterial colonization of the airways and the subsequent increased risk of infection should be carefully considered. Problems concerning the ventilatory circuit and monitoring can be specific in patients with a tracheal cannula and those with a nasal/facial interface. Long-term tracheostomy in itself represents a real risk for bacterial colonization, damage to the tracheal mucosa, and to functioning of the vocal cords (both for speech and swallowing): therefore, a switch from invasive to noninvasive ventilatory interface may be proposed. Most problems with the nasal mask interface concern air leakage and the skin mucosal lesions. Two major aspects must be taken into account when considering the long-term effects of noninvasive ventilatory support monitoring: the possible effect of CO2 rebreathing, and the inadequate volume/pressure delivery, so that proper ventilation cannot be achieved. Use of an oral/mouth interface is of limited interest in subjects with restrictive disorders: air gastric distension and orthodontic problems are the most common side-effects in chronic use.

Home Care Services↗
PubMed1996

Non-invasive mechanical ventilation in severe chronic obstructive lung disease and acute respiratory failure: short- and long-term prognosis.

OBJECTIVE: To evaluate the short- and long-term prognosis of patients with chronic obstructive lung disease (COLD) who had noninvasive mechanical ventilation (NMV) for acute respiratory failure (ARF). DESIGN: Retrospective study. SETTING: Two respiratory intermediate intensive care units. PATIENTS: Two groups of patients suffering from COLD and an ARF episode requiring mechanical ventilation. Group 1 (30 patients) was given NMV using face masks (aged 64 +/- 9 years; pH = 7.28 +/- 0.05; PaCO2 = 83 +/- 18 mmHg; PaO2/FIO2 = 141 +/- 61). Group 2 (27 patients) was composed of control patients (aged = 65 +/- 8 years; pH = 7.26 +/- 0.05; PaCO2 = 75 +/- 17 mmHg; PaO2/FIO2 = 167 +/- 41) given MV using endotracheal intubation (EI) when clinical and functional conditions had further deteriorated because the medical therapy failed and NMV was not available at the time. Causes of ARF were in group 1 and 2 respectively: pneumonia in 8 (27%) and 11 (41%), acute exacerbation of COLD in 19 (63%) and 14 (52%) and pulmonary embolism in 3 (10%) and 2 (7%) patients. MEASUREMENTS AND RESULTS: Success rate, mortality during stay in ICU (at 3 months and at 1 year), and the need for rehospitalization during the year following ARF were measured in this study. Group 1 showed a success rate of 74%, only 8/30 patients needing EI and conventional MV. In group 2, the weaning success was 74% (20/27 patients). The mortality for group 1 was 20% in IICU, 23% at 3 months and 30% at 1 year; and 26% for group 2 in ICU, 48% at 3 months and 63% at 1 year. Within each group 1-year mortality was greater (p < 0.01) in patients with pneumonia. The number of new ICU admissions during the follow-up at 1 year was 0.12 versus 0.30 in groups 1 and 2 respectively (p < 0.05). CONCLUSION: For patients suffering from COLD who have undergone ARF, avoiding EI by early treatment with NMV is associated with better survival in comparison to patients bound to invasive MV. Pneumonia as a cause of ARF may worsen the prognosis in both groups of patients.

Acute Disease↗