RESUMEN
The aim of our study was to evaluate the modifications of the respiratory pattern during sleeping in patients with congestive heart failure (CHF) by a simple pulse-oxymetry. We studied 10 subjects (8M/2F), mean age 71.4 +/- 12.4 yrs, admitted to sub-intensive cardiological therapy unit, with diagnosis of CHF due to left ventricular insufficiency by ischemic, hypertensive or idiopathic cardiopathy, when in a stable clinical condition. All patients presented arterial blood gas values within normal limits. The ejection fraction of left ventricle showed a mean value of 30.4 +/- 8.2% (range 20%-45%). Nocturnal pulse-oxymetry was performed by pulse-oxymeter (PULSOX 7 Minolta) provided with a digital probe at a sliding speed 24 cm/h. Our data showed that all patients presented nocturnal desaturation episodes (mean oxygen desaturation index 15.7 +/- 18.4). In two patients, we found an "Overlap Syndrome" (obstructive sleep apnoea in presence of cardiopathy). In other patients pulse-oxymetry showed a typical sequence of "fall-rise" basal O2 saturation lasting from 36 to 72 seconds, collected in "wave trains" which were present from 14% to 70% of total sleep time compatible with periodic breathing. In conclusion, our study shows that patients affected by CHF, even if in stable condition and with a PaO2, within normal values, present more or less severe disturbances of nocturnal SaO2, with periodic and regular sequences of SaO2 fall-rise that may be referred to ventilatory troubles such as periodic breathing or Cheyne-Stokes breathing. In these patients the pulse-oxymetry may be considered an efficacious, simple, cheap and well tolerated method.
Asunto(s)
Insuficiencia Cardíaca/metabolismo , Hipoxia/metabolismo , Oxígeno/metabolismo , Parasomnias/metabolismo , Anciano , Femenino , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/fisiopatología , Humanos , Hipoxia/etiología , Hipoxia/fisiopatología , Masculino , Oximetría/métodos , Parasomnias/etiología , Parasomnias/fisiopatologíaRESUMEN
It is unknown whether daytime features predict oxygenation during sleep in COPD patients with normoxaemia or mild hypoxaemia. In this study our purpose was to evaluate by a pulse oxymeter, nocturnal desaturation in 33 COPD with PaO2 > 60 mmHg and to examine some daytime parameters as possible predictors of nocturnal hypoxaemia. A significant nocturnal desaturation has been defined by spending > or = 30% of total sleep-time with a TSTSaO2 < 90% > 30. According to this criterion we classified our patients in Desaturators (D) and Non Desaturators (ND). Our results showed that 39% of our patients were D and 61% ND. Among anthropometric and respiratory functional data we found that daytime SaO2B (r = 0.74 p < 0.001) daytime PaO2 (r = 0.47 p < 0.01) and daytime PaCO2 (r = 0.45 p < 0.05) were significantly correlated with the nocturnal oxygen desaturation and can predict the presence of sleep related hypoxaemia. In conclusion, our study confirms that a relatively high percentage of COPD patients with normoxaemia or borderline hypoxaemia exhibits significant nocturnal hypoxaemia. Further studies will suggest whether sleep related hypoxaemia deserves nocturnal oxygen therapy.