Schönhofer B, Sonneborn M, Haidl P, Kemper K, Köhler D
Fachkrankenhaus Kloster Grafschaft, Zentrum für Pneumologie und Allergologie, Schmallenberg-Grafschaft.
Pneumologie. 1995 Dec;49(12):689-94.
The essential cause for long-term mechanical ventilation with unweanability from respirator is chronic failure of the inspiratory muscles. Principally two different causes exist for chronic respiratory failure: Primary pulmonary diseases with overload or load imbalance of primarily uncompromised respiratory muscles, and neuromuscular diseases with a significant decrease in respiratory muscle capacity. Intermittent nocturnal ventilation (INV) leads to recovery by unloading the respiratory pump. In the present retrospective study we examined the value of INV in the "post-weaning-phase" for previously unweanable, long term ventilated patients. In two years (1993 and 1994) 43 patients who had been ventilated for 57.5 +/- 60.3 days in outward intensive care units (ICU) in a predominantly assisted mode we could wean from the respirator within 8.4 +/- 5.5 days by means of consequently applying an individually adapted, volume cycled weaning regime. In all patients, on admission to our ICU and before discharge blood gases, P0.1, Pimax, breathing frequency and tidal volume were measured during spontaneous breathing. After weaning in about 40% of our patients we decided to initiate INV with intermittent positive pressure ventilation (IPPV). The indication for INV after weaning depended on whether a chronic hypercapnic respiratory failure continued to be demonstrable. In this group of patients, INV was the essential stabilizing factor for continuous weaning success, as the respiratory muscles recovered during the ensuing inpatient phase and the daytime PaCO2 normalised. In most of our patients (14 out of 18) INV could be performed non-invasively via breathing masks. Only 4 out of 18 patients continued to be long-term ventilated invasively via tracheostomy. The remaining patients (25 out of 43) showed normoventilation at daytime during the ensuing inpatient phase so they did not need INV. At the time of the patients' referral to our ICU, there was no predictive value regarding the ultimate indication for INV after weaning from respirator.
长期机械通气且无法脱机的根本原因是吸气肌慢性衰竭。慢性呼吸衰竭主要有两种不同原因：原发性肺部疾病导致原本未受损的呼吸肌负荷过重或负荷失衡，以及神经肌肉疾病导致呼吸肌能力显著下降。间歇性夜间通气（INV）通过减轻呼吸泵负荷实现恢复。在本回顾性研究中，我们探讨了INV在“脱机后阶段”对先前无法脱机的长期通气患者的价值。在两年（1993年和1994年）期间，43例在外部重症监护病房（ICU）以主要辅助模式通气57.5±60.3天的患者，通过持续应用个体化、容量控制的脱机方案，在8.4±5.5天内成功脱机。所有患者在入住我们的ICU时以及出院前，均在自主呼吸时测量血气、口腔阻断压（P0.1）、最大吸气压（Pimax）、呼吸频率和潮气量。在约40%的患者脱机后，我们决定采用间歇性正压通气（IPPV）启动INV。脱机后INV的指征取决于慢性高碳酸血症性呼吸衰竭是否持续存在。在这组患者中，INV是持续脱机成功的关键稳定因素，因为在随后的住院期间呼吸肌得到恢复，日间动脉血二氧化碳分压（PaCO2）恢复正常。在我们的大多数患者（18例中的14例）中，INV可通过呼吸面罩无创进行。18例患者中只有4例继续通过气管切开进行长期有创通气。其余患者（43例中的25例）在随后的住院期间日间通气正常，因此不需要INV。在患者转诊至我们的ICU时，对于脱机后INV的最终指征没有预测价值。
