慢性心不全患者の重症度による夜間無呼吸と低酸素血症の比較

type:原著

type:Original

慢性心不全(CHF)患者の重症度による夜間の酸素飽和度(SaO_2)と無呼吸の比較について検討を行うために安定した慢性軽症心不全患者6例(男4例,女2例63±5.2歳,左室駆出率:49.8±3.4%,NYHA class:IかII,mild-CHF群)と安定慢性重症心不全患者11例(男9例,女2例,62±11.9歳,左室駆出率:25.6±8.6%,NYHA class:III,severe-CHF群)患者を対象とし,両群を比較することにより検討を行った.全例において室内空気下にパルスオキシメーターを用いて24時間のSaO_2と脈拍数を連続記録した.そして夜間のSaO_2が3%あるいは4%以上低下した1時間あたりの回数(3%ODI,4%ODI),SaO_2の最低値を各々分析した.さらにポリソムノグラフィーを用いてSaO_2と睡眠に関する全てのデータを連続的に記録分析した.その結果,severe-CHF群のODIはmild-CHF群に比して有意に高値であった(4%ODI;5.8±5.1 vs 0.6±0.5,p<O.01.3%ODI;8.6±7.1 vs 1.0±O.9,p<0.01.).severe-CHF群のSaO_2の最低値はmild-CHF群に比して有意に低かった(82.2±7.1 vs 91.7±1.0%,p<0.01).severe-CHF群の夜間無呼吸は全例にみられ,大多数が中枢型であった(74.0±3.6%).以上より安定した重症心不全では夜間に低酸素血症と無呼吸がみられ,これらが臨床病像の悪化に影響していることが示唆される.

Background : Patients with chronic heart failure (CHF) commonly experience Cheyne- Stokes respiration, central apnea, or obstructive apnea during sleep associated with oxygen desaturation. Nocturnal oxygen therapy and nasal continuous positive airway pressure (NCPAP) reduce sleep-disordered breathing in stable CHF. However, the relation between sleep apnea and nocturnal desaturation inpatients with severe, stable CHF in Japan is unknown. Objectives : To examine nocturnal oxygen saturation (SaO_2) and sleep apnea in Japanese patients with severe, stable CHF. Methods : The subjects were 11 patients with severe, stable CHF (9 men and 2 women, LVEF=25.6±8.6%, NYHA class=III, severe CHF group) and 6 with mild, stable CHF (4 men and 2 women, LVEF=49.8±3.4 %, NYHA class=I or II, mild CHF group). SaO_2 was continuously recorded with a pulse oximeter under room air, and 4 % and 3 % SaO_2 dip rate per hour (GDIs) and the SaO_2 nadir were analyzed. In addition, SaO_2 and sleep variables were continuously recorded with a polysomnograph. Results : ODI frequency in the severe CHF group was significantly higher than that in the mild CHF group (4% ODI, 5.8±5.1 vs 0.6±0.5 times/hour, respectively, p<0.01;3 % ODI, 8.6±7.1 vs 1.0±0.9 times/hour, respectively, p<0.01.). SaO_2 nadir in the severe CHF group was significantly lower than that in the mild CHF group (82.2±7.1 vs 91.7±1.0 %, p<0.01). All severe patients had sleep apnea, predominantly of the central type (74.0±3.6%). Conclusion : The frequency of nocturnal hypoxemia and apnea increases in patients with severe, stable CHF. Nocturnal hypoxemia and apnea may adversely effect the clinical status of these patients.

identifier:3

identifier:KJ00004161774