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PubMed1998

[Atelectasis of the maxillary sinus. Analysis of progression stages. Apropos of 4 cases].

We analyzed atelectasic processes occurring in the maxillary sinus. Several publications in the literature have tempted to analyze the pathogenesis. Clinically the processes are often silent and only revealed when the major opthalmological complication, enophthalmia, becomes patent. In other cases there is a long history of chronic sinusitis. There is a spectacular retraction of the maxillary sinus walls leading to collapse of the orbital floor and enophthalmia. We report four cases of maxillary sinusitis with atelectasia of the sinus walls at different stages of progression. These observations and data in the literature emphasize the importance, whatever the state of development, of endoscopic osteal decompression to avoid ophthalmological complications.

Adolescent↗
PubMedDate not supplied

Acute pleuropulmonary complications detected by computed tomography following myocardial revascularization.

INTRODUCTION: Pleuropulmonary changes are common following coronary artery bypass grafting surgery performed with a saphenous vein graft, with or without an internal mammary artery. The presence of atelectasis or pleural effusions reflects the thoracic trauma. PURPOSE: To define the postoperative incidence of changes in the lung and in the pleural space and to evaluate the influence of the trauma. METHODS: Thirty patients underwent elective coronary artery bypass grafting surgery (8 saphenous vein grafts and 22 saphenous vein grafts and internal mammary artery grafts with pleurotomy). Chest tubes in the left pleural space were used in all internal mammary artery patients. On the second (day 2) and seventh (day 7) postoperative day, patients underwent a computed tomography, and pleural effusions were rated as follows: grade 0 = no fluid to grade 4 = fluid in more than 75% of the hemithorax. Atelectasis was rated as follows: laminar = 1, segmental = 3, and lobar = 10 points. RESULTS: All patients had pleural effusion or atelectasis. Between day 2 and day 7, the number of patients with effusions or atelectasis on the right side decreased (P < 0.05). The incidence of effusions on day 2 in the saphenous vein graft group (87.5%) was higher (P < 0.05) than in the internal mammary artery group (52.3%). The incidence of atelectasis in the lower right lobe decreased (P < 0.05) from 86.7% (day 2) to 26.7% (day 7). The degree of atelectasis in both sides did not differ on day 2 (P = 0.42) but did on day 7 (P < 0.0001). There was a decrease in the atelectasis from day 2 to day 7 on the right side (P < 0.001), but not on the left (P = 0.21). On day 2 there was a relationship between atelectasis and effusion on the right (P = 0.04), but not on the left (P = 0.113). CONCLUSION: The present series demonstrates that there is a high incidence of both minimal pleural effusion and atelectasis after coronary artery bypass grafting surgery, which drops on the right side from day 2 to day 7 post surgery. Factors that contribute to the persistence of changes on the left side include the thoracic trauma and the presence of chest tubes and pericardial effusion.

Acute Disease↗
PubMed2004

Two new radiological findings to improve the diagnosis of bronchial foreign-body aspiration in children.

Our objective was to report on two new chest X-ray signs (hyperinflation or obstructive emphysema with atelectasis in the same hemithorax, and aeration within an area of atelectasis) in children with foreign-body aspiration (FBA). We performed a retrospective review of clinical characteristics and chest X-ray films of 133 children with FBA. Of 133 children, 45% were under 3 years old. History of a choking crisis was present in 101 (75.8%); however, it was only elicited upon follow-up questioning in 33 children (32.7%). Early foreign-body (FB) extraction (<24 hr) was performed in 17.3%; removal took place between 1-7 days in 29.3%. The site of aspirated FBs was bronchial in 78.9%, laryngeal in 6%, and tracheal in 4.5%, with mobile FB in the trachea/bronchi in 4.5%. The chest X-ray was normal in 11.3%. Positive findings included: radiopaque FB (23.3%); hyperinflation or obstructive emphysema (21.8%); hyperinflation or obstructive emphysema with atelectasis in the same hemithorax (18%); lobar atelectasis (12.8%); whole-lung atelectasis (6.8%); shift of mediastinal shadow (11%); and aeration within an area of atelectasis (6%). In conclusion, if a history of choking crisis is not present in a child with suspected FBA, two previously undescribed radiological signs (hyperinflation or obstructive emphysema with atelectasis in the same hemithorax, and aeration within an area of atelectasis) should be sought in order to improve the utility of chest-X ray for early diagnosis of FBA.

Adolescent↗
PubMed1987

Computerized tomography of the chest and gas exchange measurements during ketamine anaesthesia.

The effects of atelectasis on pulmonary gas exchange were studied in eight supine, clinically lung-healthy patients. Atelectasis was studied by computerized tomography (CT), and gas exchange by blood gas analysis. The distribution of ventilation/perfusion ratios was assessed by a multiple inert gas elimination technique. No patient had any signs of atelectasis in the awake state, and gas exchange was normal. During ketamine anaesthesia and spontaneous breathing, lung ventilation and perfusion were well matched in most subjects. In one patient there was perfusion of poorly ventilated regions amounting to 14% of cardiac output, and in another there was a shunt of 4% of cardiac output; this patient was the only one who developed atelectasis in dependent lung regions. After muscular relaxation and commencement of mechanical ventilation, all patients but one developed both shunt (2-6% of cardiac output) and atelectasis. The shunt correlated to the size of atelectasis. It is concluded that the occurrence of shunt during anaesthesia is related to the development of atelectasis in dependent lung region, which is consistent with the hypothesis that it is changes in chest-wall mechanics that cause atelectasis.

Adult↗
PubMedDate not supplied

Survival analyses of patients with thoracic complications secondary to bronchial carcinoma at the time of diagnosis.

BACKGROUND: The impact on survival of thoracic complications secondary to bronchial carcinoma has not been clearly analyzed. OBJECTIVES: The purpose of this study was to assess the significance of these complications for the survival of lung cancer patients. METHODS: All patients diagnosed at our center from March 2000 to January 2004 were analyzed to estimate survival among patients with or without thoracic complication. Any intrathoracic change or abnormality secondary to bronchial carcinoma such as atelectasis or pleural effusion was defined a thoracic complication. Survival was calculated using the Kaplan-Meier method, and the complications predicting survival were evaluated using Cox's regression analysis. RESULTS: Of the 182 eligible patients, 61.5% had at least one thoracic complication. The complications were atelectasis, pulmonary metastases, pleural effusion, laryngeal nerve involvement, vena cava superior syndrome and others. Specific survival times for each complication were not different, except in the case of atelectasis. Median survival was significantly longer in patients with atelectasis, as opposed to nonatelectatic patients. Survival times in patients with at least one complication were not different than those of patients without complication. However, median survival of patients with one of the complications, excluding atelectasis (since this was associated with improved survival), was 3 months shorter (p = 0.029). Cox's regression analysis also predicted atelectasis for improved survival. CONCLUSION: Atelectasis, which was determined to be the most frequent thoracic complication, was identified as a favorable prognostic factor in patients with advanced stage lung cancer.

Aged↗
PubMed1995

Postoperative physical therapy after coronary artery bypass surgery.

Coronary artery bypass surgery is frequently complicated by postoperative atelectasis. Although routinely prescribed, the efficacy of any specific chest physical therapy is not well established. We studied patients at a university center undergoing elective coronary artery bypass surgery. Based upon chest X-ray criteria at extubation, patients (n = 228) were classified as demonstrating greater or lesser degrees of atelectasis. Those with a lesser degree of atelectasis were randomized to receive either early mobilization or sustained maximal inflations (SMI). Those with greater a degree of atelectasis were separately randomized to receive either SMI or single-handed percussions (SSP). We found the extent of atelectasis at extubation did not predict the risk of developing pneumonia. Hospital stays and intensive care unit stays were similar regardless of treatment. Physical therapy costs were highest in the most labor-intensive therapy group (SSP). We conclude that postoperative respiratory dysfunction is common but does not commonly cause significant morbidity or prolong hospital stay. Adding SMI to patients with minimal atelectasis at extubation does not improve clinical outcomes. Similarly, adding SSP to patients with marked atelectasis does not improve outcomes over those obtained with SMI and early ambulation.

Aged↗
PubMed1949

A study of inflation of the lungs of the newborn; a preliminary report.

There seems to be no reasonable doubt that the lungs in a newborn expand progressively during the first few days of life. Some degree of atelectasis seems to be perfectly normal. This is indicated by a number of roentgenographic studies (including those here reported); by the reported findings of pathologists; by the fact that in experimental animals the lungs inflated very unevenly; and by the fact that aeration of only a portion of the lung is needed for complete oxygenation of the blood. The relation of atelectasis to neonatal death is not entirely clear and is probably not always the same. The infant may die from other causes before the lungs are fully expanded. Atelectasis may develop secondarily to other debilitating conditions. The frequent coincidence of prematurity and extensive atelectasis is impressive. It may be that the lungs are so incompletely formed that they cannot expand. On the other hand, atelectasis and massive collapse in the adult is a serious condition and there seems to be no good reason to suppose that this cannot also occur in infants and be serious per se. The air pressures found necessary to expand the lungs in rabbit fetuses were found to be about ten times what adult humans use in quiet respiration and were of about the same magnitude as the pressures found necessary to expand the lungs of stillborn humans. An attempt to produce atelectasis in newborn rabbits by chilling was most inconclusive. Atelectasis did develop in three of 15 animals used in the experiment, but the relation to chilling was not at all clear.

Adult↗
PubMed1988

The effect of pleural pressure on the hypoxic pulmonary vasoconstrictor response in closed chest dogs.

The effect of intrapleural pressure on the hypoxic pulmonary vasoconstrictor (HPV) responses to atelectasis and hypoxia were measured in two groups of anesthetized closed chest dogs. The right lung was continuously ventilated with 100% O2. The left lung was initially ventilated with 100% O2 (hyperoxia) but subsequently underwent either reabsorption atelectasis (atelectasis; group I) or ventilation with a hypoxic gas mixture (hypoxia; group II). The mean intrapleural pressure in the left hemithorax was 5.4 cm H2O during hyperoxia, but with left lung atelectasis decreased significantly to -3.8 cm H2O by 15 minutes and to -4.2 cm H2O by 90 minutes. Venous admixture (% VA) increased significantly from 10.3% during hyperoxia to 33.2% at 15 minutes of left lung atelectasis and to 34.6% at 90 minutes. However, after sternotomy with the left lung still atelectatic, the %VA decreased significantly to 25.4% For the hypoxia group, %VA increased significantly from 9.2% during hyperoxia to 29.9% at 15 minutes of left lung hypoxia and 25.1% at 90 minutes. HPV diverted blood flow away from both atelectatic lung and hypoxic lung. However, due to the negative intrapleural pressure generated during left lung resorption atelectasis when the chest was closed, HPV was less effective during atelectasis than during hypoxia.

Animals↗
PubMed1995

CT-assessment of dependent lung densities in man during general anaesthesia.

PURPOSE: We aimed to describe the frequency of atelectasis occurring during anaesthesia, to describe the size and pattern of the atelectasis, and to standardise the method of identifying the atelectasis and calculate its area. MATERIAL AND METHODS: Patients (n = 109) scheduled for elective abdominal surgery were examined with CT of the thorax during anaesthesia. RESULTS: In 95 patients (87%) dependent pulmonary densities were seen, interpreted as atelectasis. Two different types of atelectasis were found-homogeneous (78%) and non-homogeneous (9%). Attenuation values in histograms of the lung and atelectasis were studied using 2 methods of calculating the atelectatic area. CONCLUSION: On the basis of the present findings, we defined atelectasis as pulmonary dependent densities with attenuation values of -100 to +100 HU.

Adolescent↗
PubMed1996

[Color Doppler echography in the study of obstruction-related lung collapse].

The typical US pattern of obstructive atelectasis consists in a triangular hypoechoic area with anechoic bands inside related to fluid-filled bronchial structures--the US fluid bronchogram sign. According to some authors, this US sign within a chest mass indicates pulmonary parenchyma disease. Furthermore, it suggests the diagnosis of lung collapse. Sixty-one patients with obstructive atelectasis confirmed with conventional radiography, conventional and computed tomography, and bronchoscopy were submitted to B-mode and color-Doppler US to assess the importance of the US fluid bronchogram sign in obstructive pulmonary atelectasis. In this condition, B-mode US showed tubular anechoic bands in 59/61 patients. Power Doppler venous sampling showed a Doppler spectrum with marked phase oscillations. Arterial sampling showed a Doppler spectrum with high distal impedance-with poor or totally absent diastolic component. To conclude, in the atelectasis area, B-mode US showed in 96% of patients some anechoic bands with no apparent pulsatility. Color-Doppler showed color flow in 100% of cases, which confirmed the vascular nature of the masses. Thus, the US fluid bronchogram, which is frequently described in the literature, was never observed in our series. Power Doppler spectral flow analysis can be useful in the diagnosis of obstructive atelectasis because it depicts the hemodynamics of atelectasis parenchyma. Indeed, the arterial spectrum with high distal resistance is consistent with the effects of hypoxia on intra-atelectatic blood vessels. Further research is necessary to assess the role of color-Doppler US in the hemodynamic study of intra-atelectatic vessels. However, our preliminary results open new perspectives for the acquisition of physiopathologic data on abnormal blood flow in obstructive atelectasis.

Adult↗
PubMed1991

Altered cellular immune function in the atelectatic lung.

Pulmonary atelectasis is common and may predispose the lung to infection. We have previously shown that atelectasis impairs alveolar macrophage antibacterial function. This study examines the effect of atelectasis on the cytotoxic function of lymphocytes harvested from the bronchoalveolar space of atelectatic lung segments by bronchoalveolar lavage. Specifically, we studied natural killer and lectin-dependent cell-mediated cytotoxicity in peripheral blood and bronchoalveolar lavage lymphocytes from the atelectatic lower lobes and contralateral normal lobes in a group of 8 dogs. We observed a decline of natural killer and lectin-dependent cell-mediated cytotoxicity to 62.7% and 61.5%, respectively, of preatelectasis control values in the affected lung lobes (p less than 0.01). Simultaneous measurements of cytotoxic activity of bronchoalveolar lavage lymphocytes harvested from the unaffected contralateral normal lungs were comparable with control values. On the other hand, natural killer and lectin-dependent cell-mediated cytotoxicity activities in peripheral blood lymphocytes were significantly increased in animals having right lower lobe atelectasis (166.7% and 154.7% of pretreated normal control, respectively, p less than 0.01). Atelectasis was also associated with an influx of polymorphonuclear leukocytes into the bronchoalveolar compartment. These findings confirm the presence of natural killer cells and cytotoxic lymphocytes in the bronchoalveolar compartment and demonstrate an atelectasis-induced impairment of local bronchoalveolar lymphocyte function. Such a dysfunction of local lung cellular host defenses may render the atelectatic lung susceptible to infection.

Animals↗
PubMed1982

Mechanical factors and the regulation of perfusion through atelectatic lung in pigs.

The role of mechanical interdependence in the perfusion of atelectatic lung was studied in two ways: a) regional hemodynamics were compared before (control) and after the development of lobar and sublobar atelectasis, and b) the effect of thoracotomy on regional hemodynamics was assessed. With lobar atelectasis mean lobar blood flow and vascular conductance decreased to 60% of control. Sublobar atelectasis caused mean sublobar blood flow and vascular conductance to decrease to 6% of control. Opening the chest after production of lobar atelectasis caused blood flow to fall to 50% of control. When sublobar atelectasis was produced in the open chest, sublobar blood flow decreased to 25% of control measurements made prior to thoracotomy. We conclude that with a closed chest, sublobar vascular distortion mediated by mechanical interdependence may be an important mechanism responsible for the differences in hemodynamic responses to atelectasis between lobes and sublobar regions.

Animals↗
PubMed1976

Postoperative impairment of mucous transport in the lung.

Impairment of mucous transport is considered significant to the postoperative development of atelectasis, but the association has never beed demonstrated in humans. Tantalum powder, which adheres to airway mucus, can be used to study mucociliary transport. The postoperative clearance of insufflated tantalum powder (mean diameter, 2.5 mum) was investigated in 25 patients. Eighteen patients underwent intra-abdominal vascular surgery and 7 undersent lower-extremity orthopedic procedures. At the completion of surgery, tantalum was insufflated into both lungs of each patient to outline a representative sample of airways from the trachea to the small bronchi. Tantalum clearance was evaluated from serial radiographs obtained immediately after insufflation, at approximately 6, 18, 26, and 48 hours later, and thereafter whenever appropriate. In the 7 orthopedic patients, clearance of tantalum was progressive and usually complete within 48 hours. Atelectasis did not occur in this group. In 14 of the 18 patients who had abdominal surgery, mucociliary clearance was markedly abnormal in that tantalum was retained for up to 6 days. Pooling of tantalum-labeled mucus occurred in dependent bronchi in 16 of these 18 patients. Pooling preceded and always accompanied radiographically visible atelectasis. Lobar atelectasis occurred in 6 patients and segmental atelectasis in 8. Tantalum-labeled mucus moved peripherally in atelectatic lobes or segments and was retained in these bronchi until re-expansion took place. Thus, impaired ciliary function and mucous transport are associated with and implicated in postoperative pulmonary atelectasis.

Aged↗
PubMed1996

[A study of surgical treatment in lung cancer over 75 years of age-effect of epidural anesthesia for protection of postoperative coughing disturbance].

29 patients over 75 years of age in 221 patients undergoing resection of lung cancer from January of 1990 through December of 1994 were studied for the occurrence of expectoration disturbance (atelectasis), the effect of epidural anesthesia for protection of it. Atelectasis was observed in 8 (27.6%) of 29. In a group received epidural anesthesia (EA) during the early postoperative phase, 1 of 5 patients developed atelectasis. In 192 patients below 75 years of age, atelectasis was observed in 40 (20.8%) of them, so in a group received epidural anesthesia (EA) during the early postoperative phase, only 2 of 42 patients (4.8%) developed atelectasis. This value was significantly lower than that value (25.3%) in a group without EA. In conclusion, in the group below 75 years of age, EA during the early postoperative phase may be useful in inhibiting the occurrence of atelectasis, an important one of the postoperative lung complications.

Aged↗
PubMed2002

Inhibition of matrix metalloproteinases in gerbil cholesteatoma: preliminary findings.

OBJECTIVES: This study was conducted to examine the role of matrix metalloproteinases (MMPs) and the impact of a topical MMP inhibitor, ilomostat, on the development of tympanic membrane (TM) atelectasis in the gerbil model. METHODS: Eustachian tubes were cauterized bilaterally in 19 gerbils. Thereafter, both TMs received once-daily topical treatment for 8 weeks with ilomostat or vehicle or no treatment (n = 6 or 7 per group). TM atelectasis was serially graded, and TMs were harvested at 8 weeks. Gelatin zymograms were performed to determine MMP activity. RESULTS: The mean activity levels of proenzyme and active MMP-9 and MMP-2 and degree of atelectasis did not differ between groups. TM atelectasis did not correlate to levels of enzymes across individual samples. CONCLUSIONS: Topical application of an MMP inhibitor did not significantly prevent the development of TM atelectasis. It remains to be determined whether the use of MMP inhibitors may prevent the progression of atelectasis in humans.

Animals↗
PubMed2002

Loss of FEV1 in cystic fibrosis: correlation with HRCT features.

The purpose of this study was to determine which high-resolution computed tomography (HRCT) features in patients with cystic fibrosis are most strongly associated with functional impairment as expressed by forced expiratory volume in one second (FEV1). Forty-seven patients with cystic fibrosis underwent chest HRCT and had pulmonary function tests. The HRCT examinations were evaluated for 11 features scored using a modification of Bhalla system and FEV1 was recorded as percentage of the predicted value. Univariate and multivariate correlations between HRCT scores and FEV1 were performed. The most common HRCT feature was bronchiectasis (98%) followed by atelectasis-consolidation (81%), bronchial wall thickening (77%), tree-in-bud sign (74%), mucous plugging (72%) and mosaic perfusion pattern (47%). On univariate analysis the following features correlated strongly with FEV1: bronchial wall thickening ( p<0.0000001), tree-in-bud sign ( p<0.0000001), mucous plugging ( p<0.0000001), atelectasis-consolidation (p<0.0000001), thickening of interlobular septa ( p<0.0002), severity ( p<0.0002) and extent of bronchiectasis ( p<0.0002). On multivariate analysis bronchial wall thickening and atelectasis-consolidation were the strongest independent determinants of the FEV1. We found a regression equation between FEV1 and the two HRCT features: FEV1=constant variable+a multiplied by bronchial wall thickening+b multiplied by atelectasis-consolidation (a and b=regression coefficients, R(2)=0.48). The major morphological determinants of functional abnormality in cystic fibrosis, as expressed by the loss of FEV1, are bronchial wall thickening and atelectasis-consolidation.

Adolescent↗
PubMed2004

[Quantification of atelectases in artificial respiration: spiral-CT versus dynamic single-slice CT].

PURPOSE: Dynamic CT (dCT) allows visualization and quantification of ventilated lung and atelectases with high temporal resolution during continuous ventilation. This study compares a quantitative image analysis in a subcarinal single slice dCT series versus a whole lung spiral-CT, in order to analyze, whether the distribution of atelectasis of a single dCT series is representative for the whole lung. MATERIALS AND METHODS: dCT in sliding windows technique (slice thickness 1 mm, temporal increment 100 ms) was performed in 8 healthy pigs 3 cm caudal to the carina during continuous mechanical ventilation. Subsequently, a spiral-CT of the whole lung (slice thickness 2 mm; pitch 1.5; increment 2 mm) was acquired during inspiratory breath hold (airway pressure 20 mbar). Lung segmentation and planimetry of predefined density ranges were achieved using a dedicated software tool in both data-sets. Thus, the fractions of the following functional lung compartments were averaged over time: hyperinflated lung (- 1024 to - 910 HE), normal ventilated lung -900 to -300 HE) and atelectasis (-300 to +200 HE). RESULTS: Quantitative analysis of dCT-series during continuous respiration correlated with the density analysis in spiral-CT as follows: hyperinflated lung r = 0.56; normal ventilated lung r = 0.83 and atelectases r = 0.84. Analysis of spiral-CT showed the following distribution of functional lung compartments: hyperinflated lung 3.1% normal ventilated lung 77.9% and atelectasis 19.0%. In dCT, hyperinflated lung represented 6.4%, normal ventilated lung 65.2% and atelectasis 28.4% of total the lung area. CONCLUSION: The results of our study demonstrate that dCT allows monitoring of atelectasis formation in response to different ventilatory strategies. However, a deviation between dCT and spiral-CT has to be taken into account. In subcarinal dCT series, hyperinflated lung areas and atelectases were overestimated due to a craniocaudal gradient of atelectases, whereas normal ventilated lung was underestimated.

Animals↗
PubMed2003

Optimal oxygen concentration during induction of general anesthesia.

BACKGROUND: The use of 100% oxygen during induction of anesthesia may produce atelectasis. The authors investigated how different oxygen concentrations affect the formation of atelectasis and the fall in arterial oxygen saturation during apnea. METHODS: Thirty-six healthy, nonsmoking women were randomized to breathe 100, 80, or 60% oxygen for 5 min during the induction of general anesthesia. Ventilation was then withheld until the oxygen saturation, assessed by pulse oximetry, decreased to 90%. Atelectasis formation was studied with computed tomography. RESULTS: Atelectasis in a transverse scan near the diaphragm after induction of anesthesia and apnea was 9.8 +/- 5.2 cm2 (5.6 +/- 3.4% of the total lung area; mean +/- SD), 1.3 +/- 1.2 cm2 (0.6 +/- 0.7%), and 0.3 +/- 0.3 cm2 (0.2 +/- 0.2%) in the groups breathing 100, 80, and 60% oxygen, respectively (P < 0.01). The corresponding times to reach 90% oxygen saturation were 411 +/- 84, 303 +/- 59, and 213 +/- 69 s, respectively (P < 0.01). CONCLUSION: During routine induction of general anesthesia, 80% oxygen for oxygenation caused minimal atelectasis, but the time margin before unacceptable desaturation occurred was significantly shortened compared with 100% oxygen.

Adult↗