Critical analysis of the utility of initial pleural aspiration in the diagnosis and management of suspected malignant pleural effusion

INTRODUCTION:Current guidelines recommend an initial pleural aspiration in the investigation and management of suspected malignant pleural effusions (MPEs) with the aim of establishing a diagnosis, identifying non-expansile lung (NEL) and, at times, providing a therapeutic procedure. A wealth of research has been published since the guidelines suggesting that results and outcomes from an aspiration may not always provide sufficient information to guide management. It is important to establish the validity of these findings in a 'real world' population. METHODS:A retrospective analysis was conducted of all patients who underwent pleural fluid (PF) sampling, in a single centre, over 3 years to determine the utility of the initial aspiration. RESULTS:A diagnosis of MPE was confirmed in 230/998 (23%) cases, a further 95/998 (9.5%) were presumed to represent MPE. Transudative biochemistry was found in 3% of cases of confirmed MPE. Positive PF cytology was only sufficient to guide management in 45/140 (32%) cases. Evidence of pleural thickening on CT was associated with both negative cytology (χ2 1df=26.27, p<0.001) and insufficient samples (χ2 1df=10.39, p=0.001). In NEL 44.4% of patients did not require further procedures after pleurodesis compared with 72.7% of those with expansile lung (χ2 1df=5.49, p=0.019). In patients who required a combined diagnostic and therapeutic aspiration 106/113 (93.8%) required further pleural procedures. CONCLUSIONS:An initial pleural aspiration does not achieve either definitive diagnosis or therapy in the majority of patients. A new pathway prioritising symptom management while reducing procedures should be considered

Evaluación de las repercusiones hemodinámicas y cardiovasculares del síndrome hipoventilación-obesidad y efectos del tratamiento

La obesidad es la enfermedad metabólica de mayor prevalencia en el mundo occidental y se asocia a una elevada morbimortalidad, constituyendo un grave problema de salud, social y económico. Se considera una epidemia global, y teniendo en cuenta el aumento alarmante de su prevalencia, especialmente de la obesidad masiva, es esperable, en los próximos años un aumento en la incidencia de una de sus complicaciones, el síndrome hipoventilación-obesidad (SHO).(1-3) En el SHO grave es frecuente hallar una sobrecarga del ventrículo derecho (SVD) e hipertensión pulmonar (HP);(4, 5) sin embargo, en el momento en que se planteó el estudio, no existía suficiente información en la literatura médica respecto al efecto hemodinámico de la ventilación no invasiva (VNI), a diferencia de lo que ocurre en el síndrome de apnea obstructiva durante el sueño (SAOS), en el que se ha demostrado que el tratamiento con presión continua positiva en la vía aérea (CPAP) -con un adecuado cumplimiento- puede revertir la HP.(6) En el SHO, el impacto de las comorbilidades en general y de las cardiovasculares en particular, así como el de la adherencia a la VNI, no han sido estudiados en profundidad, a diferencia del SAOS.(7-9) Son necesarios más estudios en el SHO, dirigidos a mejorar el conocimiento de su repercusión hemodinámica y cardiovascular, con el fin de optimizar el tratamiento teniendo en cuenta que ya en 2004 era la principal causa de indicación de ventilación domiciliaria en Francia (10) y en el 2005 suponía el 68% de las indicaciones de VNI crónica en Lugo. Con el objetivo de profundizar en la fisiopatología del SHO y del impacto que sobre ella tiene el tratamiento, llevamos a cabo dos estudios para: [1º] valorar sus repercusiones hemodinámicas -particularmente la prevalencia de SVD- y la influencia del tratamiento sobre las mismas; [2º] estudiar si la mortalidad y la morbimortalidad cardiovascular difieren entre los pacientes con SHO tratados con VNI y los pacientes con SAOS tratados con CPAP e [3º] identificar factores predictores de mortalidad en los pacientes con SHO

Obesity-hypoventilation syndrome: increased risk of death over sleep apnea syndrome.

AIM:To study whether mortality and cardiovascular morbidity differ in non-invasive ventilation (NIV)-treated patients with severe obesity-hypoventilation syndrome (OHS) as compared with CPAP-treated patients with obstructive sleep apnea syndrome (OSAS), and to identify independent predictors of mortality in OHS. MATERIAL AND METHODS:Two retrospective cohorts of OHS and OSAS were matched 1:2 according to sex, age (± 10 year) and length of time since initiation of CPAP/NIV therapy (± 6 months). RESULTS:Three hundred and thirty subjects (110 patients with OHS and 220 patients with OSAS) were studied. Mean follow-up time was 7 ± 4 years. The five year mortality rates were 15.5% in OHS cohort and 4.5% in OSAS cohort (p< 0.05). Patients with OHS had a 2-fold increase (OR 2; 95% CI: 1.11-3.60) in the risk of mortality and 1.86 fold (OR 1.86; 95% CI: 1.14-3.04) increased risk of having a cardiovascular event. Diabetes, baseline diurnal SaO2 < 83%, EPAP < 7 cmH2O after titration and adherence to NIV < 4 hours independently predicted mortality in OHS. CONCLUSION:Mortality of severe OHS is high and substantially worse than that of OSAS. Severe OHS should be considered a systemic disease that encompasses respiratory, metabolic and cardiovascular components that require a multimodal therapeutic approach

Kaplan Meier curves for time to first cardiovascular event.

<p>Kaplan Meier curves for time to first cardiovascular event.</p

Univariate analysis of risk factors related to mortality in OHS patients.

<p>SaO2: oxygen saturation; NIV: non invasisve ventilation; CPAP: continuous positive airway pressure; EPAP: expiratory positive airway pressure; IPAP: inspiratory positive airway pressure; BIPAP: bilevel positive airway pressure; CVE: cardiovascular events; HF: heart failure.</p><p>Univariate analysis of risk factors related to mortality in OHS patients.</p

Independent predictors of mortality on Multivariate Analysis for OHS patients.

<p>Independent predictors of mortality on Multivariate Analysis for OHS patients.</p

Epworth sleepiness scale, basal arterial blood gas results, sleep study findings and therapeutic intervention for the 2 cohorts.

<p>Values are expressed as mean ± SD or No. of patients (%). PaO2: arterial oxygen pressure; PaCO2: arterial carbon dioxide pressure; AHI: apnea-hypopnea index; DI4: nocturnal desaturation ≥ 4% index; CT90%: cumulative percentages of sleep time with SaO₂ <90%; CPAP: continuous positive airway pressure; NIV: non invasive ventilation; IPAP: inspiratory positive airway pressure; EPAP: expiratory positive airway pressure.</p><p>Epworth sleepiness scale, basal arterial blood gas results, sleep study findings and therapeutic intervention for the 2 cohorts.</p

Flow-chart diagram of the study.

<p>Flow-chart diagram of the study.</p

Demographic characteristics, cardiovascular risk factors and history of cardiovascular disease of the 2 cohorts.

<p>Values are expressed as mean ± SD or No. of patients (%). BMI: body mass index.</p><p>Demographic characteristics, cardiovascular risk factors and history of cardiovascular disease of the 2 cohorts.</p