Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “ASPIRATION”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,081 records · Page 60Linked to original sources
PubMed1996

Routine preoperative gastric emptying is seldom indicated. A study of 85,594 anaesthetics with special focus on aspiration pneumonia.

BACKGROUND: The aim of this study was to determine the incidence and severity of pulmonary aspiration of gastric contents during anaesthesia, to determine the short- and long-term morbidity, and to evaluate present routines for preoperative gastric emptying. During the study period, preoperative gastric emptying was done only when intestinal obstruction was suspected. METHODS: We routinely record prospectively all problems during and after anaesthesia by means of a database. All data for the 5 years from 1989 to 1993, a total of 85594 anaesthetic procedures, were analyzed. The hospital charts were also reviewed for those patients where aspiration to the lungs had occurred. RESULTS: Pulmonary aspiration of gastric contents was detected in 25 cases; all occurred in patients receiving general anaesthesia. The incidence was 4.1 times higher in emergency procedures than in electives. There were no aspirations in 30199 patients receiving regional anaesthesia. The complication occurred in all phases of anaesthesia, but clinical morbidity was low in most cases. Three cases showed serious morbidity immediately after the event, but recovered. Two cases showed serious long-term morbidity, but also recovered completely. No patients died. No cases, except possibly one, might have been prevented by stricter routines for preoperative gastric emptying. CONCLUSION: We found a low incidence of pulmonary aspiration. When it occurs, it carries a low risk for serious morbidity. Emergency cases for general anaesthesia are most at risk. Regional anaesthesia is considered safe. There is no evidence that preoperative gastric emptying should be routinely done in emergency cases, except in patients with suspected ileus/ subileus.

Anesthesia↗
PubMed1992

Meconium aspiration syndrome: the role of resuscitation and tracheal suction in prevention.

We reviewed our experience of meconium staining of liquor and meconium aspiration syndrome over a 33 month period. The clinical and radiological severity of disease was assessed in comparison with tracheal suction and resuscitation. Sixty (27%) of newborns with meconium stained liquor subsequently developed MAS. No association was found between the thickness of meconium or its presence on tracheal aspiration with subsequent severity of respiratory disease. However, the presence of meconium in the trachea was strongly associated with radiological abnormality. The severity of meconium aspiration syndrome and mortality were also related to the clinical stability of the infants at presentation. Our results indicate that intrauterine aspiration and pulmonary maladaptation may play a significant role in meconium aspiration syndrome rather than resuscitative events at delivery.

Humans↗
PubMed1993

Scintigraphic detection of gastro-pulmonary aspiration in patients with respiratory disorders.

The scintigraphic detection of small nocturnal aspirations of radio-labelled gastric contents is difficult in the presence of high remaining activity in the abdomen, causing a non-uniform background activity. This problem was examined in phantom experiments and a technique for interpolative background correction was further developed. The accuracy of this technique was found to be influenced by the distance between the lung and the abdominal source of activity, and the minimum detectable 'aspirated' activity was determined as 0.1 MBq at a distance of 15 cm and 1 MBq at 5 cm. The interpolative technique for background correction was evaluated on healthy volunteers and laryngectomized patients, examined 10 h after intragastric instillation of 200 MBq of 99Tcm-pertechnetate. After background subtraction, their calculated pulmonary mean net count value was comparable to that registered before the radioactive tracer was administered. No localized accumulation of activity was found in any of these controls. The technique was then applied clinically to 55 patients with chronic respiratory disorders and symptoms of gastroesophageal reflux. Aspiration was detected in 11 patients (20%). Five aspirators had asthma, two a chronic cough of unknown origin, two recurrent pulmonary infections, and one chronic bronchitis and chronic laryngitis respectively. Aspiration was detected among patients with and without demonstrated pathological gastroesophageal reflux.

Adult↗
PubMed1996

Risk factors for meconium-aspiration syndrome.

The aim of this retrospective study was to identify risk factors for meconium-aspiration syndrome, and to identify antenatal and intrapartum risk factors which might be preventable. We analyzed maternal and neonatal records of the 210 infants who had meconium-stained liquor and who also developed respiratory distress necessitating admission to the Special Care of Intensive Care Baby Units at National Women's Hospital, Auckland in 1992. Meconium-aspiration syndrome occurred in 6.6% of meconium exposed babies and in 1.3% of total births. Severe meconium-aspiration syndrome developed in 18 infants, moderate in 48, mild in 60 respiratory distress in 84. An association was found between meconium aspiration syndrome and primiparity (p = 0.001) and Pacific Island ethnicity (p = 0.0002). An association was also found between the severity of meconium and low umbilical artery pH (p = 0.0002). Thick meconium and an abnormal cardiotocograph were more common in severe meconium-aspiration syndrome. All deaths and long-term morbidity occurred in babies with abnormal cardiotocographs or in unmonitored infants. Preventable antenatal and intrapartum factors were not identified in this study.

Adult↗
PubMed1993

Comparison of medical abortion with surgical vacuum aspiration: women's preferences and acceptability of treatment.

OBJECTIVES: To assess women's preferences for, and the acceptability of, medical abortion and vacuum aspiration in the early first trimester. DESIGN: Patient centred, partially randomised trial. Medical abortion was performed with mifepristone 600 mg followed 48 hours later by gemeprost 1 mg vaginal pessary. Vacuum aspiration was performed under general anaesthesia. SETTING: Teaching hospital in Scotland. PATIENTS: 363 women undergoing legal induced abortion at less than nine weeks' gestation. MAIN OUTCOME MEASURES: Women's preferences for method of abortion before abortion; acceptability judged two weeks after abortion by recording the method women would opt to undergo in future and by semantic differential rating technique. RESULTS: 73 (20%) women preferred to undergo medical abortion, and 95 (26%) vacuum aspiration; 195 (54%) were willing to undergo either method, and were allocated at random. Both procedures were highly acceptable to women with preferences. Gestation had a definite effect on acceptability in randomised women; at less than 50 days there were no differences, but between 50 and 63 days vacuum aspiration was significantly more acceptable. CONCLUSIONS: Women who wish to use a particular method should be allowed their choice, regardless of gestation. Women of 50-63 days' gestation without preferences for a particular method are likely to find vacuum aspiration more acceptable. A patient centred, partially randomised trial design may be a useful tool in pragmatic research.

Abortifacient Agents, Nonsteroidal↗
PubMed1989

Foreign body aspiration in the adult: an occult cause of chronic pulmonary symptoms.

We describe two otherwise healthy subjects with many years sequelae due to lung aspiration. In both, diagnosis was delayed due to lack of history of aspiration. Recurrent pneumonia in the same segment in one, and migratory pneumonia in the other, could have suggested the diagnosis. Review of the literature shows that occult foreign body aspiration poses difficulties in diagnosis and that often a history of aspiration is lacking. However, the recurrent nature and the localization of the pneumonia, as well as the findings during bronchoscopy, should alert the physician to the possibility of foreign body aspiration.

Aged↗
PubMed2000

Acid aspiration increases sensitivity to increased ambient oxygen concentrations.

Previously we have demonstrated that prolonged exposure to 100% ambient oxygen leads to a marked loss in functional lung volume and lung compliance, hypoxemia, and surfactant system abnormalities similar to acute respiratory distress syndrome (ARDS). However, 50% oxygen administration is believed to be safe in most clinical settings. In the present study, we have evaluated the effects of a 24-h exposure to 50% oxygen in rabbits immediately following experimental gastric acid aspiration. Mild hypoxemia, but no changes in mortality, lung volume, lung compliance, surfactant metabolism, or edema formation occurred after 24 h of normoxia postacid aspiration. Conversely, a relatively short (24-h) exposure to 50% oxygen after acid aspiration results in increased pulmonary edema, physical signs of respiratory distress, and mortality, as well as decreased arterial oxygenation, lung volume, lung compliance, and type II alveolar cell surfactant synthesis. These results suggest that acid aspiration alters the "set point" for oxygen toxicity, possibly by "priming" cells through activation of inflammatory pathways. This pathogenic mechanism may contribute to the progression of aspiration pneumonia to ARDS.

Air↗
PubMed1994

High incidence of silent aspiration in elderly patients with community-acquired pneumonia.

Pneumonia is a major cause of death in the elderly. To investigate the role of silent aspiration in community-acquired pneumonia, we examined the occurrence of silent aspiration during sleep in 14 elderly patients with acute episode of pneumonia and 10 age-matched control subjects by a new technique using indium111 chloride. Scanning of the thorax demonstrated that 71% of patients aspirated, whereas aspiration was observed in only 10% of control subjects. The percentage of positive scans was significantly higher in patients with acute episode of pneumonia than in control subjects (p < 0.02). The results may indicate an important role of silent aspiration in the development of community-acquired pneumonia in the elderly.

Acute Disease↗
PubMed1976

Pulmonary aspiration of gastric contents.

A retrospective analysis of 50 patients who had been observed to aspirate gastric contents was performed to define better the course of patients with this syndrome. The patients invariably had a disturbance of consciousness, most commonly due to sedative drug overdose or general anesthesia. The onset of clinical signs occurred prompty after aspiration and tended to be similar in all patients, irrespective of their subsequent course or outcome. These findings usually included fever, tachypnea, diffuse rales, and serious hypoxemia. Cough, cyanosis, wheezing, and apnea were each seen in approximately one third of the cases. Apena, shock, and early severe hypoxemia were particularly ominous events. Initial roentgenograms revealed diffuse or localized alveolar infiltrates, which progressed during the next 24 to 36 hours. Subsequent clinical courses followed 3 patterns: 12 per cent of the patients died shortly after aspiration; 62 per cent had rapid clinical and radiologic improvement, with clearing, on average, within 4.5 days; 26 per cent demonstrated rapid improvement, but then had clinical and radiographic progression associated with recovery of bacterial pathogens from the sputum and a fatal outcome in more than 60 per cent. Treatment from the outset by adrenocortical steroids or antimicrobial agents had no demonstrable effect on the outcome. The clinical features of aspiration of gastric contents are characteristic and distinguish it from other forms of aspiration-related lung disease.

Apnea↗
PubMed1979

Increased alveolar epithelial permeability with acid aspiration: the effects of high-dose steroids.

Using the in vivo, liquid-filled dog lung model, we found that aspriation of acid with a pH of 2.5 or less led to increased alveolar epithelial permeability for albumin (molecular weight, 69,000 daltons; molecular radius, 35 a) and exogenously administered, polydispersed dextrans (molecular weight, 150,000 to 170,000 daltons: approximately molecular radius, 100 a). This increased permeability occurred with a large-volume (3 to 5 ml/kg) or small-volume (1 to 1.5 ml/kg) aspirate and with acid nebulization (1 to 1.5 ml/kg). When animals were either pretreated (30 min before aspiration) or post-treated (30 min after aspiration) with 30 mg of methylprednisolone/kg of body weight, there was no improvement in the increased permeability associated with acid aspiration. We conclude that, acutely, steroids have no effect on the increased alveolar epithelial permeability associated with acid aspiration.

Albumins↗
PubMed2002

Dysphagia and aspiration with unilateral vocal cord immobility: incidence, characterization, and response to surgical treatment.

To objectively determine the incidence of dysphagia associated with unilateral vocal cord immobility (UVCI) and to evaluate the potential for response to vocal cord medialization, we made videofluoroscopic swallowing (VFS) recordings of patients with newly diagnosed UVCI and prospectively analyzed them in a blinded fashion using the Penetration-Aspiration Scale (PAS) and pharyngeal transport function measures. A subset of patients underwent vocal cord medialization and were evaluated with a postoperative VFS study. Comparison was made between preoperative and postoperative VFS results to study the effects of vocal cord medialization in this setting. Eighty-seven VFS recordings were studied in 64 adult patients with UVCI; 23 patients underwent VFS testing before and after vocal cord medialization. The UVCI was most commonly left-sided (53 cases) and most commonly resulted from thoracic or cardiac surgery (53.1%), followed by malignancy (15.6%). Overall, the median PAS score was 2.0 (25th-75th percentiles, 1.0-5.0), with 20 patients (31.3%) and 15 patients (23.4%) exhibiting penetration or aspiration, respectively. No significant differences in swallowing function were noted between surgical and nonsurgical causes of paralysis (PAS scores of 2.0 and 2.0, respectively; p = .901). The median PAS score improved from 4.0 to 3.0 (p = .395, Wilcoxon paired samples test) in patients studied after undergoing a vocal cord medialization procedure (6 laryngoplasties and 17 vocal cord injections). Laryngoplasty was not more successful than vocal cord injection in resolving aspiration (p = .27). Radiographically significant penetration or aspiration occurs in approximately one third of patients with UVCI, independent of the cause of paralysis. Vocal cord medialization may not be as effective as thought for eliminating aspiration in these patients.

Deglutition↗
PubMedDate not supplied

Incidence of gastroesophageal reflux and aspiration in mechanically ventilated patients using small-bore nasogastric tubes.

BACKGROUND: Use of a large-bore nasogastric tube (NGT) and patient position are considered key factors in promoting gastroesophageal reflux (GER) and pulmonary aspiration in critically ill patients. The objective of this study was to determine the incidence of GER and pulmonary aspiration of gastric contents in mechanically ventilated (MV) patients using small-bore NGTs. METHODS: We studied 30 patients on mechanical ventilation for acute respiratory failure who tolerated enteral nutrition through a small-bore NGT. Patients were randomly assigned to a group with (n = 16) or without (n = 14) a small-bore NGT and were maintained in a semirecumbent position during the study. GER and aspiration of gastric contents were assessed by a radioisotopic technique. Scans were done 24 hours after technetium-99m administration (n = 30). In 9 patients a dynamic scintigraphy was performed immediately after colloid administration, and samples of blood and tracheal and oropharyngeal secretions were obtained basally, 30 minutes, and 24 hours after technetium administration and analyzed for radioactivity using a gamma counter. RESULTS: Both groups were similar in age, underlying diagnosis, number of days of mechanical ventilation at the day of study, and mortality. There were no GER reaching the oropharynx and aspiration of gastric contents in both groups. CONCLUSIONS: GER and aspiration of gastric contents were not detected in MV patients using small-bore NGTs and may be a simple measure to prevent ventilator-associated pneumonia.

Female↗
PubMedDate not supplied

Physiology of the aerodigestive system and aberrations in that system resulting in aspiration.

BACKGROUND: Aspiration pneumonia remains a significant and often devastating problem in critically ill patients. It is unclear whether aspiration pneumonia occurs because of problems in the handling of oropharyngeal secretions or if the reflux of gastric contents is the major etiological factor. Additionally, the obvious breakdown of upper aerodigestive protective mechanisms in the critically ill patient population is largely unstudied. Finally, the impact and contribution of tubes, both endotracheal and nasoenteral, on aspiration pneumonia is unclear. METHODS: A Medline literature search on scientific and review articles concerning the normal physiology of the aerodigestive tract and factors that compromised normal physiology was undertaken. Readings were supplemented by expert outside opinion from researchers in these fields and from the combined expertise from a multidisciplinary panel of experts assembled at a recent summit on aspiration pneumonia. RESULTS: Changes in the normal physiology of the aerodigestive tract are vast and varied and dependent on the response to injury, iatrogenic interventions, and the use of nasoenteral and endotracheal tubes. The effects on gastric and esophageal motility are likely dynamic and represent an ongoing but changing risk of reflux for the patient. Nasoenteral and endotracheal tubes likely compromise upper aerodigestive protective mechanisms. CONCLUSIONS: More research is needed on the functioning of the aerodigestive protective mechanisms in critically ill patients. Understanding of the dynamic changes in gastrointestinal motility will also be an important factor to decrease the incidence of aspiration pneumonia in this patient population.

Digestive System↗
PubMedDate not supplied

Aspiration pneumonia: incidence, mortality, and at-risk populations.

Pulmonary aspiration in the hospitalized patient can be devastating. Most aspiration events occur in patients with a swallowing disorder. Aspiration can be divided into 3 separate etiologies: oropharyngeal bacteria, particulate matter, and acidified gastric contents. Reported prevalence data are extremely variable, ranging from 10% to 70%. Mortality is related to the volume and content of the aspirate and is reported to be as high as 70%. Neurologic dysfunction, decreased consciousness, advancing age, gastroesophageal reflux, and tube feeding are all potential risk factors for the development of aspiration.

Enteral Nutrition↗
PubMed2001

A spoonful of sugar--improving the sensitivity of the glucose oxidase test strip method for detecting subclinical pulmonary aspiration of enteral feed.

A 74-year-old woman was admitted to the intensive care unit (ICU) with respiratory failure. Following intubation and mechanical ventilation, nasogastric enteral feeding was begun. The sensitivity of the glucose oxidase strip method for detecting aspiration of enteral feed has been questioned because the glucose levels in commonly used feeds are similar to those of normal tracheal aspirates. In order to increase the glucose concentration of the feed, 10 g of glucose was added to each 500 ml feed carton. Testing oral and tracheal secretions with standard glucose oxidase strips allowed the accurate detection of both pharyngeal regurgitation and tracheal aspiration. An episode of subclinical aspiration was detected and this was associated with a fall in the PaO2/FiO2 ratio. There were no further episodes of aspiration following the introduction of a gastric motility agent, maintaining the patient in the semi-recumbent position and an increase in the positive end expiratory pressure (PEEP).

Aged↗
PubMedDate not supplied

Long-term enteral access in aspiration-prone patients.

Aspiration pneumonia is a serious complication of enteral feeding. Many critically ill patients are particularly at risk for aspiration. Few studies have rigorously compared various access devices. Risk factors for aspiration and studies examining aspiration associated with enteral feeding devices are reviewed. We recommend a surgical jejunostomy for all patients at high risk for aspiration who require more than 3 weeks of enteral nutrition support.

Comorbidity↗
PubMed1997

Methylprednisolone attenuates the pulmonary hypertensive response in porcine meconium aspiration.

Severe neonatal aspiration of meconium is frequently complicated by fatal pulmonary hypertension. The protective effect of an i.v. bolus of methylprednisolone on meconium aspiration-induced hypertensive lung injury was studied in anesthetized pigs with adapted lung circulation. Eleven 10-wk-old pigs received 3 mL/kg 20% human meconium via the endotracheal tube. Five of them were pretreated with 30 mg/kg methylprednisolone 30 min before aspiration. Ventilator settings were adjusted to keep arterial PO2 above 8 kPa and arterial PCO2 below 5 kPa. Meconium insufflation induced a biphasic pulmonary pressor response during the 6 h follow-up. Methylprednisolone tended to prevent the early (0-1 h) increase in pulmonary artery pressure and inhibited significantly the second phase (1-6 h) progressive rise in pulmonary artery pressure and pulmonary vascular resistance. This inhibition of resistance increase was most profound in the postarterial segment of the lung circulation, as determined by pulmonary artery occlusion. Additionally, the methylprednisolone pretreated group demonstrated a significant decrease in venous admixture together with improved oxygenation during the late phase after the insult, and further showed evidence of diminished lung edema formation. Although meconium aspiration-induced fall in blood leukocyte concentration was inhibited by methylprednisolone pretreatment, no histologic difference was found in pulmonary leukocyte sequestration. Our results thus show that in adapted porcine lungs methylprednisolone pretreatment improves oxygenation and attenuates the meconium aspiration-induced pulmonary hypertensive response by preventing the increase in the postarterial resistance.

Animals↗
PubMed2001

Newborn piglets with meconium aspiration resuscitated with room air or 100% oxygen.

We investigated whether newborn piglets exposed to hypoxemia and severe meconium aspiration could be reoxygenated with room air as efficiently as with 100% O(2). Twenty-one 2- to 5-d-old piglets were randomly divided into three groups: 1) the room air group: hypoxemia, meconium aspiration, and reoxygenation with room air (n = 8); 2) the O(2) group: hypoxemia, meconium aspiration, and reoxygenation with 100% O(2) (n = 8); and 3) the control group: meconium aspiration, and reoxygenation with room air (n = 5). Hypoxemia was induced by ventilation with 8% O(2) until the mean blood pressure reached <20 mm Hg or the base excess reached <-20 mM. At this point, reoxygenation was started with either room air or 100% O(2). Three milliliters per kilogram of meconium 110 mg/mL was instilled into the trachea immediately before the start of reoxygenation. The O(2) tension in arterial blood was significantly lower in the room air group; at 5 min of reoxygenation it was 9.1 +/- 0.5 kPa versus 43.5 +/- 6 kPa in the O(2) group (p < 0.05). At 5 min of reoxygenation the tidal volume per kilogram was 12.1 +/- 0.7 mL/kg in the room air group and 13.1 +/- 0.9 mL/kg in the O(2) group (NS). There were no significant differences between the room air and the O(2) groups during 120 min of reoxygenation in mean arterial blood pressure, pulmonary arterial pressure, cardiac index, base excess, or plasma hypoxanthine. In conclusion, hypoxic newborn piglets with meconium aspiration were found to be reoxygenated as efficiently with room air as with 100% O(2).

Animals↗