翻譯：唐劍 編輯：馮玉蓉 審校：曹瑩
背景：術中低血壓與術後發病率和早期死亡率有關。然而，術後低血壓的研究較少。本研究假設術後低血壓的嚴重程度和持續時間都與心肌損傷有關。
方法：本項單中心觀察隊列研究納入1710名60歲或60歲以上接受中到高風險非心臟手術的患者。記錄患者術後24小時內血流動力學的監測情況。多重平均動脈壓(MAP)絕對閾值(50~75 mmHg)用於定義低血壓，其標準為MAP下的累計分鐘數、持續時間和時間加權平均值。主要評價指標是術後前3天的心肌損傷程度(高敏肌鈣蛋白T峰值為50 ng/L或更高)。
結果：術後低血壓常見，其中血壓累計2小時低於60 mmHg者144例(8%)，血壓累計4小時小於75 mmHg者824例(48%)。混雜因子調整後，患者術後血壓低於75 mmHg且時間長於635min與心肌損傷相關。多閾值比較，MAP閾值低於60 mmHg累計2~4h，MAP閾值小於65 mmHg和70 mmHg超過4h也與心肌損傷相關。在調整了術中低血壓後，相關性仍然顯著，因此術中低血壓作為獨立因素與心肌損傷無關。
結論：在本研究中，術後低血壓是常見的，並且與心肌損傷獨立相關。
文獻來源： Liem VGB, Hoeks SE, Mol KHJM, et al. Postoperative Hypotension after Noncardiac Surgery and the Association with Myocardial Injury.Anesthesiology, 2020, 09;133(3).
Postoperative Hypotension after Noncardiac Surgery and the Association with Myocardial Injury
Abstract
Background: Intraoperative hypotension has been associated with postoperative morbidity and early mortality. Postoperative hypotension, however, has been less studied. This study examines postoperative hypotension, hypothesizing that both the degree of hypotension severity and longer durations would be associated with myocardial injury.
METHODS: This single-center observational cohort was comprised of 1,710 patients aged 60 yr or more undergoing intermediate- to high-risk noncardiac surgery. Frequent sampling of hemodynamic monitoring on a postoperative high-dependency ward during the first 24 h after surgery was recorded. Multiple mean arterial pressure (MAP) absolute thresholds (50 to 75 mmHg) were used to define hypotension characterized by cumulative minutes, duration, area, and time-weighted-average under MAP. Zero time spent under a threshold was used as the reference group. The primary outcome was myocardial injury (a peak high-sensitive troponin T measurement 50 ng/l or greater) during the first 3 postoperative days.
Results: Postoperative hypotension was common, e.g., 2 cumulative hours below a threshold of 60 mmHg occurred in 144 (8%) patients while 4 h less than 75 mmHg occurred in 824 (48%) patients. Patients with myocardial injury had higher prolonged exposures for all characterizations. After adjusting for confounders, postoperative duration below a threshold of 75 mmHg for more than 635min was associated with myocardial injury (adjusted odds ratio, 2.68; 95% CI, 1.46 to 5.07, P = 0.002). Comparing multiple thresholds, cumulative durations of 2 to 4 h below a MAP threshold of 60 mmHg (adjusted odds ratio, 3.26; 95% CI, 1.57 to 6.48, P = 0.001) and durations of more than 4 h less than 65 mmHg (adjusted odds ratio, 2.98; 95% CI, 1.78 to 4.98, P < 0.001) and 70 mmHg (adjusted odds ratio, 2.18; 95% CI, 1.37 to 3.51, P < 0.001) were also associated with myocardial injury. Associations remained significant after adjusting for intraoperative hypotension, which independently was not associated with myocardial injury.
CONCLUSIONS:In this study, postoperative hypotension was common and was independently associated with myocardial injury.