Debilidad pulmonar asociada a COVID-19 (DPAC): revisión sistemática y metaanálisis / COVID-19-associated lung weakness (CALW): Systematic review and meta-analysis

Objetivo: Evaluar la mortalidad y diversos factores clínicos derivados del desarrollo de neumotórax (NTX) y/o neumomediastino (NMD) atraumáticos en pacientes críticos como consecuencia de la debilidad pulmonar asociada a la COVID-19 (DPAC). Diseño: Revisión sistemática con metaanálisis. Ámbito: Unidad de cuidados intensivos (UCI). Participantes: Investigaciones originales en las que se evaluase a pacientes, con o sin necesidad de ventilación mecánica invasiva (VMI), con diagnóstico de COVID-19 que hubiesen desarrollado NTX o NMD atraumáticos al ingreso o durante su estancia hospitalaria. Intervenciones: Se obtuvieron los datos de interés de cada artículo que fueron analizados y evaluados por la Escala Newcastle-Ottawa. El riesgo de las variables de interés principales se evaluó por los datos derivados de los estudios que incluyeron a pacientes que desarrollaron NTX o NMD atraumáticos. Variables de interés principales: Mortalidad, estancia media en la UCI y PaO2/FiO2 media en el momento diagnóstico. Resultados: Se recogieron datos de 12 estudios longitudinales. En el metaanálisis se incluyeron datos de un total de 4.901 pacientes, entre los cuales 1.629 presentaron un episodio de NTX y 253 de NMD atraumáticos. A pesar de encontrar asociaciones significativamente fuertes, la alta heterogeneidad entre los estudios hace que la interpretación de los resultados deba hacerse con cautela. Conclusiones: La mortalidad de los pacientes con COVID-19 fue mayor en los que desarrollaron NTX y/o NMD atraumáticos con respecto a los que no lo hicieron. La media del índice PaO2/FiO2 fue menor en los pacientes que desarrollaron NTX y/o NMD atraumáticos. Proponemos agrupar bajo el término DPAC estos casos. (AU)

Objectives: To assess mortality and different clinical factors derived from the development of atraumatic pneumothorax (PNX) and/or pneumomediastinum (PNMD) in critically ill patients as a consequence of COVID-19-associated lung weakness (CALW). Design: Systematic review with meta-analysis. Setting: Intensive care unit (ICU). Participants: Original research evaluating patients, with or without the need for protective invasive mechanical ventilation (IMV), with a diagnosis of COVID-19 who had developed atraumatic PNX or PNMD on admission or during their hospital stay. Interventions: Data of interest were obtained from each article and analysed and assessed by the Newcastle-Ottawa Scale. The risk of the variables of interest was assessed by data derived from studies including patients who developed atraumatic PNX or PNMD. Main variables of interest: Mortality, mean ICU length of stay and mean PaO2/FiO2 at diagnosis. Results: Data were collected from 12 longitudinal studies. Data from a total of 4,901 patients were included in the meta-analysis. A total of 1,629 patients had an episode of atraumatic PNX and 253 patients had an episode of atraumatic PNMD. Despite finding significantly strong associations, the high heterogeneity between studies means that interpretation of the results should be made with caution. Conclusions: Mortality of COVID-19 patients was higher in those who developed atraumatic PNX and/or PNMD compared to those who did not. The mean PaO2/FiO2 index was lower in patients who developed atraumatic PNX and/or PNMD. We propose to group these cases under the term CAPD. (AU)

Barotrauma in Coronavirus Disease 2019 Patients Undergoing Invasive Mechanical Ventilation: A Systematic Literature Review.

OBJECTIVE: There are concerns of a high barotrauma rate in coronavirus disease 2019 patients with acute respiratory distress syndrome receiving invasive mechanical ventilation. However, a few studies were published, and reported rates were highly variable. We performed a systematic literature review to identify rates of barotrauma, pneumothorax, and pneumomediastinum in coronavirus disease 2019 acute respiratory distress syndrome patients receiving invasive mechanical ventilation. DATA SOURCE: PubMed and Scopus were searched for studies reporting barotrauma event rate in adult coronavirus disease 2019 patients receiving invasive mechanical ventilation. STUDY SELECTION: We included all studies investigating adult patients with coronavirus disease 2019 acute respiratory distress syndrome requiring mechanical ventilation. Case reports, studies performed outside ICU setting, and pediatric studies were excluded. Two investigators independently screened and selected studies for inclusion. DATA EXTRACTION: Two investigators abstracted data on study characteristics, rate of pneumothorax, pneumomediastinum and overall barotrauma events, and mortality. When available, data from noncoronavirus disease 2019 acute respiratory distress syndrome patients were also collected. Pooled estimates for barotrauma, pneumothorax, and pneumomediastinum were calculated. DATA SYNTHESIS: A total of 13 studies with 1,814 invasively ventilated coronavirus disease 2019 patients and 493 noncoronavirus disease 2019 patients were included. A total of 266/1,814 patients (14.7%) had at least one barotrauma event (pooled estimates, 16.1% [95% CI, 11.8-20.4%]). Pneumothorax occurred in 132/1,435 patients (pooled estimates, 10.7%; 95% CI, 6.7-14.7%), whereas pneumomediastinum occurred in 162/1,432 patients (pooled estimates, 11.2%; 95% CI, 8.0-14.3%). Mortality in coronavirus disease 2019 patients who developed barotrauma was 111/198 patients (pooled estimates, 61.6%; 95% CI, 50.2-73.0%). In noncoronavirus disease 2019 acute respiratory distress syndrome patients, barotrauma occurred in 31/493 patients (6.3%; pooled estimates, 5.7%; 95% CI, -2.1% to 13.5%). CONCLUSIONS: Barotrauma occurs in one out of six coronavirus disease 2019 acute respiratory distress syndrome patients receiving invasive mechanical ventilation and is associated with a mortality rate of about 60%. Barotrauma rate may be higher than noncoronavirus disease 2019 controls.

The long-term prognosis of pneumomediastinum associated with dermatomyositis: a two-centre retrospective cohort study.

OBJECTIVES: Pneumomediastinum (PnM) is a rare but life-threatening complication of DM. The present study aims to characterize the long-term prognosis and prognostic factors of DM-associated PnM. METHODS: Inpatients with DM-associated PnM were retrospectively enrolled from two tertiary referral centres for rheumatic disease. The enrolled patients were divided into survivors or non-survivors. Information about the demographics, clinical manifestations, CT scan features, laboratory findings and outcomes were collected from their medical records. A least absolute shrinkage and selection operator regularized Cox regression model was used to select the most relevant factors. Prognosis was analysed using a Kaplan-Meier curve. A Cox proportional hazards model was used to identify independent predictive factors for long-term survival. RESULTS: A total of 62 patients (26 women) with DM-associated PnM were enrolled. The mean age was 44.3 years (s.d. 11.7). The median follow-up duration was 17 days (quartiles 7, 266.5). Thirty-five patients died during follow-up. The survival rates were 75.4% at 1 week, 46.2% at 3 months and 41.9% at 1 year. The Cox proportional hazards model identified the development of fever [hazard ratio (HR) 3.23 (95% CI 1.25, 8.35), P = 0.02] and a decrease in the number of lymphocytes [HR 2.19 (95% CI 1.10, 4.39), P = 0.03] as independent risk factors for death. CONCLUSION: The results suggest poor overall survival among patients with DM-associated PnM. Survival during the first 3 months is crucial for long-term survival. Meanwhile, the development of fever and a decrease in the number of lymphocytes were associated with long-term mortality. Early recognition and prompt treatment of this high-risk group of DM patients is therefore important.

Spontaneous Pneumomediastinum as a Potential Predictor of Mortality in Patients with Idiopathic Pulmonary Fibrosis.

BACKGROUND: Spontaneous pneumomediastinum (PM) is a rare event in patients with idiopathic pulmonary fibrosis (IPF) with unknown prognostic implications. OBJECTIVES: To analyze the incidence and prognostic impact of PM in a cohort of patients with IPF. METHODS: PM diagnosed by computed tomography was identified retrospectively in the clinical and radiological records of 182 patients with IPF who were admitted to our center between August 2006 and July 2013. PM patients were compared to matched IPF patients not affected by PM and analyzed for survival. RESULTS: PM occurred in 9/182 IPF patients [5%; 6 males; median age: 63 years; median percent predicted of vital capacity (VC%) at baseline: 53%]. The median time between IPF diagnosis and PM occurrence was 3 months (interquartile range: 0-33). The control group included 36 IPF patients (28 males; median age: 69 years; VC% at baseline: 57%). In a multivariate Cox regression analysis, PM was a significant predictor of mortality [hazard ratio (HR): 3.0; p = 0.032]. Considering only patients experiencing PM at the time of IPF diagnosis (n = 4), PM was a strongly significant predictor of mortality in multivariate analysis (HR: 6.4; p = 0.007). CONCLUSIONS: Spontaneous PM is a rare but serious complication in patients with IPF and may be considered as a potential predictor of mortality.

Computed Tomographic Findings and Mortality in Patients With Pneumomediastinum From Blunt Trauma.

IMPORTANCE: The care of most patients with pneumomediastinum (PNM) due to trauma can be managed conservatively; however, owing to aerodigestive tract injury and other associated injuries, there is a subset of patients with PNM who are at higher risk of mortality but can be difficult to identify. OBJECTIVE: To characterize computed tomographic (CT) findings associated with mortality in patients with PNM due to blunt trauma. DESIGN, SETTING, AND PARTICIPANTS: A retrospective review of medical records from January 1, 2002, to December 31, 2011, was conducted at a university-based urban trauma center. The patients evaluated were those injured by blunt trauma and found to have PNM on initial chest CT scanning. Data analysis was performed July 2, 2013, to June 18, 2014. MAIN OUTCOMES AND MEASURES: In-hospital mortality. RESULTS: During the study period, 3327 patients with blunt trauma underwent chest CT. Of these, 72 patients (2.2%) had PNM. Patients with PNM had higher Injury Severity Scores (P < .001) and chest Abbreviated Injury Scale scores (P < .001) compared with those without PNM. Pneumomediastinum was associated with higher mortality (9 [12.5%] vs 118 [3.6%] patients; P < .001) and longer mean (SD) hospital stays (11.3 [14.6] vs 5.1 [8.8] days; P < .001), intensive care unit stays (5.4 [10.2] vs 1.8 [5.7] days; P < .001), and ventilator days (1.7 [4.2] vs 0.6 [4.0] days; P < .03). We evaluated several chest CT findings that may have predictive value. Pneumomediastinum size was not associated with in-hospital mortality (P = .22). However, location of air in the posterior mediastinum was associated with increased mortality of 25% (7 of 28 patients; P = .007). Air in all mediastinal compartments was also associated with increased mortality of 40.0% (4 of 10 patients; P = .01). Presence of hemothorax along with PNM was associated with mortality of 22.2% (8 of 36 patients; P = .01). CONCLUSIONS AND RELEVANCE: Pneumomediastinum is uncommon in patients with injury from blunt trauma; however, CT findings of posterior PNM, air in all mediastinal compartments, and concurrent hemothorax are associated with increased mortality. These CT findings could be used as a triage tool to alert the trauma surgeon to a potentially lethal injury.

Pneumomediastinum predicts early mortality in acute paraquat poisoning.

CONTEXT: In paraquat (PQ) poisoning, death often occurs after the appearance of pneumomediastinum (PM). However, the clinical features and eventual outcome of PM in PQ intoxication remains unclear. OBJECTIVE: We aimed to characterize PM following PQ poisoning and its prognostic value for predicting mortality. MATERIALS AND METHODS: Enrolled PQ-poisoned patients (n = 75) were divided into two groups according to whether PM could be detected by chest computed tomography or not. The study outcomes included 5- and 90-day death after intoxication. Survival curves were derived using the Kaplan-Meier method, and mortality risk factors were analyzed by forward stepwise Cox regression analysis. RESULTS: PM was documented in 21.3% of the patients (16/75); in 13 of them PM set in within 3 days of PQ ingestion. 15 patients died within 3 days of appearance of PM. Compared with patients without PM, those with PM were younger (P = 0.011), and had higher scores of Acute Physiology and Chronic Health Evaluation (P < 0.001) and Sequential Organ Failure Assessment (P = 0.003). In addition, patients with PM had a higher incidence of acute renal failure (P = 0.001), toxic hepatitis (P = 0.008), and respiratory insufficiency (P = 0.003). PM predicted an increased risk of 90-day death (93.8% of patients with PM vs. 40.7% among those without PM; hazard ratio [HR], 2.4; 95% confidence interval [CI], 1.0-5.6; P = 0.045), and increased risk of 5-day death (81.3% vs. 27.1%; HR, 3.2; 95% CI, 1.2-8.1; P = 0.017). DISCUSSION AND CONCLUSION: Early PM, occurring within 8 days, is a specific predictor of mortality in PQ poisoning.

Spontaneous pneumomediastinum: an extensive workup is not required.

BACKGROUND: Spontaneous pneumomediastinum is a rare entity usually caused by alveolar rupture and air tracking along the tracheobronchial tree. Despite its benign nature, an extensive workup is often undertaken to exclude hollow viscus perforation. We sought to review our experience with this condition and examine the optimal management strategy. STUDY DESIGN: We conducted a retrospective review of all radiographic pneumomediastinum cases at a tertiary hospital between 2006 and 2011. The main outcomes measures included length of hospital stay, mortality, and need for investigative procedures. RESULTS: Forty-nine patients with spontaneous pneumomediastinum were identified, including 26 male patients (53%). Mean age was 19 ± 9 years. Chest pain was the most common presenting symptom (65%), followed by dyspnea (51%). Forceful coughing (29%) or vomiting (16%) were the most common eliciting factors, and no precipitating event was identified in 41% of patients. Computed tomography was performed in 38 patients (78%) and showed a pneumomediastinum that was not seen on chest x-ray in 9 patients. Esophagography was performed in 17 patients (35%) and was invariably negative for a leak. Thirty-eight patients (78%) were hospitalized for a mean of 1.8 ± 2.6 days. No mortality was recorded. Compared with patients who presented with pneumomediastinum secondary to esophageal perforation, spontaneous pneumomediastinum patients were younger, had a lower white cell count, and were less likely to have a pleural effusion. CONCLUSIONS: Spontaneous pneumomediastinum is a benign entity and rarely correlates with true esophageal perforation. Additional investigation with esophagography or other invasive procedures should be performed selectively with the aim of expediting the patient's care. The prognosis is excellent with conservative management and the risk for recurrence is low.

Systematic review of spontaneous pneumomediastinum: a survey of 22 years' data.

OBJECTIVE: To describe and clarify management protocols in relation to spontaneous pneumomediastinum, and try to integrate criteria on this subject. BACKGROUND: Thoracic physicians are faced with patients who present with gas in the mediastinum, frequently without an obvious etiologic factor. Published material contains heterogeneous information from which different conclusions can be drawn. METHODS: In a Medline search from 1990 to 2012, we collected data on mortality, morbidity, signs, symptoms, etiologic factors, and diagnostic methods. Standardized mean differences were calculated. RESULTS: We identified 600 patients in 27 papers with series of >5 patients without precipitating or etiologic factors previous to the clinical presentation, but athletic activity, drug abuse, and history of asthma played an apparent role in the disease process. Most patients complained of thoracic pain and dyspnea, with subcutaneous emphysema and Hamman's sign. The most common complication was tension pneumothorax. Morbidity was seen in 2.8%; no mortality has been reported so far. CONCLUSION: Spontaneous pneumomediastinum is a rare disease with a benign course, which should be treated conservatively unless a complication mandates an invasive procedure. An algorithm for diagnosis and treatment is offered, based on the available evidence.

Survival analysis and risk factors for mortality in connective tissue disease-associated pneumomediastinum.

The aim of this study was to analyze the characteristics of patients with diffuse connective tissue diseases (CTDs) complicated by pneumomediastinum and identify the risk factors associated with increased mortality in these patients. Twenty-eight patients with CTD-associated pneumomediastinum, who were admitted to our hospital from January 1997 to June 2012, were prospectively studied. Their demographic characteristics, time to death, and potential risk factors were assessed. Survival curves were depicted by the Kaplan-Meier method. Univariate and multivariate survival analyses were performed by Cox regression. Of the 28 patients, 21 had dermatomyositis; two, polymyositis; three, systemic lupus erythematosus; one, polyarteritis nodosa; and one, undifferentiated CTD. The mean follow-up period was 1,461 days (54-5,264). The cumulative estimated Kaplan-Meier survival rate was 68 % at 1 week, 50 % at 1 month, and 43 % at 1 year. According to univariate analysis, higher serum albumin level (HR 0.87, 95 % CI 0.78-0.98), "slow air leak" (defined as time to progression of dyspnea [newly acquired respiratory failure, mechanical ventilation required, or decrease in PaO2 >30 mmHg after pneumomediastinum]) >3 days (HR 0.07, 95 % CI 0.02-0.34), and early initiation of immunosuppressive agents (within 1 month of steroid therapy; HR 0.27, 95 % CI 0.09-0.81) were associated with better prognosis. Final regression analysis revealed that slow air leak was associated with a lower mortality risk. We found that slow air leak was independently associated with better prognosis. Furthermore, most patients (86 %) who survived for at least 1 month following the pneumomediastinum event subsequently survived beyond 1 year.

Secondary pneumomediastinum: a retrospective comparative analysis.

Pneumomediastinum is an uncommon radiographic finding of potential clinical significance. Secondary pneumomediastinum (SPM) has a variety of etiologies that can lead to potentially morbid outcomes. There are limited data regarding the etiologies, diagnosis, and outcomes of this entity. A retrospective comparative study was conducted over an 11-year period of patients developing pneumomediastinum secondary to a specific pathologic or traumatic event. Forty-five patients were identified with an underlying condition resulting in SPM. Demographic data, radiologic findings, length of hospital stay, and mortality were recorded. Statistical comparison was conducted between patients with blunt thoracic trauma- and barotrauma-induced pneumomediastinum. Logistic and multiple linear regression analyses were performed to discover factors predictive of mortality and length of hospital stay. Median age of the patients was 40 years and 69% were men. Subcutaneous emphysema was identified in 44%, pneumothorax in 47%, and pleural effusion in 11%. Pneumomediastinum was identified by plain radiograph (CXR) in only 47% compared to 100% by computed tomogram (CT scan). Average length of hospital stay was 19 days and mortality was 38%. Patients with blunt thoracic trauma had a lower sensitivity for CXR to discover pneumomediastinum, were more likely to develop subcutaneous emphysema or pneumothorax, and had lower mortality and length of hospital stay compared with those with barotrauma-induced pneumomediastinum. Barotrauma was an independent predictor for hospital mortality. Secondary pneumomediastinum is a morbid condition with distinctive etiologies, radiologic findings, and outcomes. Barotrauma-induced pneumomediastinum is associated with a prolonged recovery and high mortality rate.

[Pulmonary air-leakage in newborn infants]. / Pulmonal luftlekkasje hos nyfødte.

BACKGROUND: Pulmonary air-leakage (PAL), especially pneumothorax, is a potentially severe complication of pulmonary disease in newborn infants. It is often related to therapeutic procedures such as resuscitation and mechanical ventilation. MATERIAL AND METHODS: This is a prospective study of infants with PAL who were born in the period 1989-2006 and were hospitalised in an intensive care unit. RESULTS: PAL occurred in 54 of 39,101 (1.4 per 1000) live-born infants; 34/54 (63%) were boys and 34/54 (63%) were born at term. 38/54 (70%) PAL cases had asphyxia and different pulmonary diseases, 16/54 (30%) PAL-incidences occurred spontaneously and 23/54 (43%) were diagnosed < 1 hour after birth. PAL occurred during resuscitation for perinatal asphyxia or initiation of mechanical ventilation in 18/54 (33%) patients, during CPAP-treatment in 12/54 (22%), and during mechanical ventilation after the start-up phase in 8/54 (15%) patients. Of 271 infants treated with mechanical ventilation, 144 (53%) were preterm infants with RDS. 64/114 (born 1992-2006) of these received a porcine surfactant and 3/64 (5%) developed PAL. The remaining 50 ventilated RDS-patients born in the same time period had a milder disease; 3/50 (6%) of these developed PAL (p > 0.05). INTERPRETATION: PAL often occurred spontaneously and shortly after birth in connection with resuscitation and stabilization for respirator treatment. The risk for PAL in mechanically ventilated infants was lower once the start-up process had been completed. In infants who had received porcine surfactant for RDS the incidence of PAL during mechanical ventilation was low.

Spontaneous thoracic air-leakage syndrome in patients following allogeneic hematopoietic stem cell transplantation: causes, CT-follow up and patient outcome.

OBJECTIVE: The purpose of this article is to describe and illustrate the acute and follow-up imaging features, clinical constellation and outcome of patients with thoracic air-leakage syndrome following allogeneic hematopoietic stem cell transplantation (allo-HCT). METHODS: Patients with evidence of thoracic air-leakage, i.e. spontaneous pneumomediastinum, spontaneous pneumothorax or interstitial emphysema after allo-HCT were retrospectively identified by a chart review. Acute and follow-up morphology, duration and patient outcome were analyzed on CT (HRCT or MSCT with HR-reconstructions). Correlation was made with histological results of transbronchial biopsy. RESULTS: The 6 patients included (3 male and 3 female, 14-64 years old) with thoracic air-leakage after allo-HCT all had histologically proven bronchiolitis obliterans (BO) or bronchiolitis obliterans organizing pneumonia (BOOP). Thoracic air-leakage consisted of spontaneous pneumomediastinum associated with active invasive pulmonary aspergillosis (IPA) in 4/6 and spontaneous pneumothorax or interstitial emphysema each in 1/6 patients. Duration of thoracic air-leakage was 7-135 days. Of the patients with spontaneous pneumomediastinum, 3/4 died of IPA. One patient survived until complete regression of spontaneous pneumomediastinum. One patient died 7 days after spontaneous pneumothorax and one survived developing chronic interstitial emphysema. CONCLUSION: In all cases, thoracic air-leakage was associated to BO or BOOP. In the majority of cases with additional IPA, thoracic air-leakage is more indicative for severity of pulmonary disease than a life-threatening entity itself.

[Pneumomediastinum complicating the anti-synthetase syndrome]. / Pneumomédiastin compliquant un syndrome des anti-synthétases.

INTRODUCTION: Pneumomediastinum is a rare but classical complication of dermatomyositis. Its development is a serious matter and necessitates prompt recourse to aggressive treatment with corticosteroids combined with immuno-suppressants or intravenous human immunoglobulin. CASE REPORT: We report the case of a 63 year old woman presenting with pulmonary infiltration, in the presence of dermatomyositis, as a clinical manifestation of the anti-synthetase syndrome. The progress was rapidly unfavourable with pneumomediastinum and acute respiratory distress despite initial treatment with corticosteroids followed by human immunoglobulin and immunosuppressants. CONCLUSION: The identification of cutaneous or muscular signs in the initial investigation of a pulmonary infiltrate should lead to a search for anti-synthetase antibodies in order to determine the optimal clinical management as quickly as possible.

Treatment by VATS of giant bullous emphysema: results.

OBJECTIVE: In selected patients with giant bullous emphysema GBE and in those with specific complications, surgery may be the treatment of choice. METHODS: In the period January 1993-February 1996 we performed 34 VATS treatments in 29 patients affected by GBE. There were 22 (76%) males and 7 (24%) females, with a mean age of 54 years (range 24 74). In 23 cases, a pneumothorax (PNX) was present at admission, while 6 patients were treated by choice. Altogether. we performed 23 resections of sessile bullae (type 2 of Reid) by using a linear endoscopic stapling device (Endo-path 35 and 45 mm) and 11 ligatures of pedicled bullae (type 1 of Reid) by loop (Endo-loop 'PDS'). The mean number of charges for every treatment was 8 (range 4-21). The largest bullae were perforated and deprived of incarcerated air. They were then twisted on the axis perpendicular to the base in order to improve the manoeuvrability of the lesion and favour the correct placement of the Endo-path or Endo-loop. GBE was bilateral in 7 cases: one of these was treated bilaterally in the same surgical stage, other 4 were treated by staged operations. RESULTS: We experienced two conversions to open thoracotomy (one sessile giant bulla inside the fissura; 1 case of strong tuberculous pleural adhesions). Two patients, underwent a second operation by open thoracotomy because of a prolonged air leak. We have two peri-operative deaths, both to respiratory failure. Altogether, in 23 out of 29 (79%) cases VATS was effective and the mean hospital stay was 6 days (range 3-16). At a mean follow up of 16 months (range 1-36) no recurrence of PNX was observed. CONCLUSIONS: VATS may be considered as a suitable surgical technique to approach GBE and, in most cases, it is effective.

Neuropericardio y neumomediastino por inhalación de cocaina

Se presentan dos pacientes que consultaron a nuestra institución por dolor pericardial luego de gran consumo de de cocaína inhalada. En ambos casos se descartó infarto agudo de miocardio; por los métodos convencionales y ecocardiografía se documentó neumoparicardio y neumomediastino.

Pulmonary barotrauma in mechanical ventilation. Patterns and risk factors.

The incidence of mediastinal emphysema (ME) and pneumothorax (PTX) was analyzed to determine the roentgenographic patterns and risk factors for the development of barotrauma in a population of mechanically ventilated patients. The roentgenograms of 139 intubated patients admitted to our medical intensive care unit over a ten-month period were evaluated for the presence of ME and PTX. Barotrauma was diagnosed in 34 of these patients, and ME was the initial manifestation in 24 patients. Of these patients with initial ME, ten subsequently developed PTX, a positive predictive value of 42 percent. The adult respiratory distress syndrome (ARDS) patient population was at highest risk for barotrauma, with an intermediate risk seen in those admitted with COPD or pneumonia. Values of peak inspiratory pressure, positive end-expiratory pressure level, respiratory rate, tidal volume, and minute ventilation were significantly elevated in patients who developed barotrauma as compared with patients who did not develop barotrauma. However, these elevations in part reflect the high incidence of barotrauma in the ARDS population, a patient group in which all of the above parameters were elevated.