手術中からのltv

オペ室から換気量制限すべき??

JA広島総合病院　救急・集中治療科櫻谷　正明

JA Hiroshima General Hospital

Journal Club

113年8月20日火曜日

手術中の換気量古くから, 低酸素や無気肺の防止のために, 全身麻酔下の患者管理では, 10-15ml/kg（IBW）の高容量の換気が推奨されてきた.

Bendixen HH, Hedley-Whyte J, Laver MB. Impaired oxygenation in surgical pa- tients during general anesthesia with con- trolled ventilation: a concept of atelecta- sis. N Engl J Med 1963;269:991-6.

しかし, 高容量にすると肺胞の過進展が生じ, VALIが起こり, 炎症性メディエーターが産生され, 全身に影響を与えるため, 多臓器不全に伸展する可能性がある.

Association between use of lung- protective ventilation with lower tidal vol- umes and clinical outcomes among pa- tients without acute respiratory distress syndrome: a meta-analysis. JAMA 2012; 308:1651-9.

213年8月20日火曜日

手術中の肺保護戦略換気量制限やPEEP, RMといった肺保護戦略はARDS患者の死亡率を低下させ, 多くの重症患者に対してのbest practiceとされている.

Putensen C, Theuerkauf N, Zinserling J, Wrigge H, Pelosi P. Meta-analysis: ventilation strategies and outcomes of the acute respiratory distress syndrome and acute lung injury. Ann Intern Med 2009; 151:566-76.

手術時からの肺保護戦略を目的とした人工呼吸器設定が有益かどうかについてはまだ疑問が残り, 日々の麻酔管理ではほとんどがNo PEEP, High tidal volumesであり, 肺保護戦略をされているのは20%以下に過ぎない.

Wrigge H, Uhlig U, Baumgarten G, et al. Mechanical ventilation strategies and inflammatory responses to cardiac sur- gery: a prospective randomized clinical trial. Intensive Care Med 2005;31:1379-87.

Jaber S, Coisel Y, Chanques G, et al. A multicentre observational study of intra- operative ventilatory management during general anaesthesia: tidal volumes and re- lation to body weight. Anaesthesia 2012; 67:999-1008.

313年8月20日火曜日

腹部手術での低容量換気.

Emmanuel Futier, M.D., Jean-Michel Constantin, M.D., Ph.D., Catherine Paugam-Burtz, M.D., Ph.D., et al. A Trial of Intraoperative Low-Tidal-Volume Ventilation in Abdominal Surgery. N Engl J Med 2013; 369:428-437.

413年8月20日火曜日

methodRCT, double-blind, 大学病院7施設, フランス, 2011年1月31日から2012年8月10日まで.

対象:

40歳以上, 少なくとも2時間以上と思われる腹部の予定手術, 周術期の肺合併症リスク >2.

除外:

手術に先立ち2週間以内に, 人工呼吸を受けている, 呼吸不全, 敗血症の既往がある.

BMI ≧35kg/m2, 進行性の神経筋疾患.

Intervention: 両群ともにVCVを用い, プラトー圧 ≦30cmH2O, SpO2 ≦92%の時は一時的にFiO2 100%にしたり, nonprotectiveでもPEEPをかけたり, RMを行うことを許可した.

nonprotective: Vt 10-12ml/kg IBW, no PEEP, no RM.

protective: Vt 6-8ml/kg IBW, PEEP 6-8cmH2O, RM 挿管後より30分毎（30cmH2O, 30秒）.

Primary outcome: 肺および肺外の合併症.

major pulmonary complication: 肺炎, IPPVやNPPVが必要.

major extrapulmonary complication: sepsis, severe sepsis, septic shock, 死亡.

513年8月20日火曜日

preoperative risk index for postoperative pulmonary complications

Risk Factor Point手術の種類　AAA repair 15　上腹部手術 10年齢　≧80歳 17　70-79歳 13　60-69歳 9　50-59歳 4機能　完全自立 10　部分的に自立 6半年で10%を超える体重減少 7COPDの既往 5

Risk Factor Point全身麻酔 4意識障害 4脳血管疾患の既往 4BUN　< 8mg/dl 4　22-30mg/dl 2　≧30mg/dl 34単位以上の輸血 3緊急手術 3慢性的なステロイド使用 31年以内の喫煙 3過去2週間以内に2回以上の喫煙 2

Risk Class points

1 ≦15

2 16-25

3 26-40

4 41-55

5 >55

613年8月20日火曜日

合併症を減少.7日以内の合併症

Nonprotective 27.5%

Protective 10.5%

• p <0.001

30日以内の合併症

Nonprotective 29.0%

Protective 12.5%

• p <0.001

T h e n e w e ngl a nd j o u r na l o f m e dic i n e

n engl j med 369;5 nejm.org august 1, 2013436

the inflammation cascade contributes to the subsequent development of lung injury31 and sys-temic organ failure.8,32

The use of very low levels of PEEP in previous trials may have promoted the repeated opening and closing of small airways, leading to atelec-tasis, which can precipitate the development of pulmonary complications.6,33 We used a multi-faceted strategy of lung-protective ventilation that combined low tidal volumes, recruitment maneuvers to open collapsed alveoli, and moder-ate levels of PEEP to prevent further collapse.34 Other strengths of the present trial include the methods used to minimize bias (blinded and centralized randomization, complete follow-up, and intention-to-treat analyses); the pragmatic nature of the trial protocol, with routine practice being maintained; and the enrollment of pa-tients with characteristics similar to those of patients enrolled in other studies analyzing out-comes after major surgery.29

Our findings are consistent with the observa-tion of transient arterial hypotension during re-cruitment maneuvers.35 Consequently, recruit-

ment maneuvers, in which hemodynamic effects are potentially influenced by the applied level of alveolar pressure,36 should be used with caution in patients with hemodynamic instability.

There are several limitations to our study. The trial design did not include standardization of the administration of fluids. However, this limi-tation is unlikely to have affected our results, since the volume of fluids administered was similar in the two groups. The definition of nonprotective ventilation was arbitrary but is supported in the literature.19,20 The trial protocol did not include standardization of requirements for noninvasive ventilation; however, it was rec-ommended that the study centers follow clinical-practice guidelines,37,38 and postoperative care was conducted by health care workers who were unaware of the study assignments. The utiliza-tion of noninvasive ventilation in our trial is close to that reported in earlier studies.37 We therefore consider it unlikely that any imbalance in interventions affected our results.

In conclusion, our study provides evidence that a multifaceted strategy of prophylactic lung-pro-tective ventilation during surgery, as compared with a practice of nonprotective mechanical ven-tilation, results in fewer postoperative complica-tions and reduced health care utilization.

Dr. Futier reports receiving consulting fees from General Electric Medical Systems, lecture fees from Fresenius Kabi, and reimbursement of travel expenses from Fisher and Paykel Healthcare. Dr Constantin reports receiving consulting fees from Baxter, Fresenius Kabi, Dräger, and General Electric Medi-cal Systems, payment for expert testimony from Baxter, Dräger, and Fresenius Kabi, lecture fees from General Electric Medical Systems, Dräger, Fresenius Kabi, Baxter, Hospal, Merck Sharp & Dohme, and LFB Biomedicaments, payment for the development of educational presentations from Dräger, General Electric Medical Systems, Baxter, and Fresenius Kabi, and reimburse-ment of travel expenses from Bird, Astute Medical, Astellas, Fresenius Kabi, Baxter, and Hospal. Dr. Paugam-Burtz reports receiving consulting fees from Fresenius Kabi, lecture fees and reimbursement of travel expenses from Astellas, and payment for the development of educational presentations from LFB Bio-medicaments and Merck Sharp & Dohme. Dr. Allaouchiche re-ports receiving consulting fees from Fresenius Kabi and lecture fees from Novartis and Astellas. Dr. Leone reports receiving consulting fees from LFB Biomedicaments and lecture fees from Fresenius Kabi and Novartis. Dr. Jaber reports receiving consult-ing fees from Dräger France and Maquet France, lecture fees from Fisher and Paykel Healthcare, Abbott, and Philips, and re-imbursement of travel expenses from Pfizer. No other potential conflict of interest relevant to this article was reported.

Disclosure forms provided by the authors are available with the full text of this article at NEJM.org.

We thank all the patients who participated in the study; the clinical and research staff at all the trial sites, without whose as-sistance the study would never have been completed; and Mervyn Singer for valuable advice during the preparation of the manuscript.

Prob

abili

ty o

f Eve

nt

0.50

0.30

0.40

0.20

0.10

0.001 3 7 3015

Days since Randomization

No. at RiskNonprotective

ventilationLung-protective

ventilation

200

200

182

192

163

184

145

179

142

176

142

175

Lung-protective ventilation

Nonprotective ventilation

Figure 2. Kaplan–Meier Estimates of the Probability of the Composite Primary Outcome.

Data for the Kaplan–Meier estimates of the probability of the composite primary outcome of major pulmonary or extrapulmonary complications were censored at 30 days after surgery. Major pulmonary complications included pneumonia or the need for invasive or noninvasive ventilation for acute respiratory failure. Major extrapulmonary complications were sepsis, severe sepsis, septic shock, and death. P<0.001 by the log-rank test for the between-group difference in the probability of the primary outcome.

The New England Journal of Medicine Downloaded from nejm.org at KOUSEIREN-HIROSHIMA-SOGO-BYOIN on August 2, 2013. For personal use only. No other uses without permission.

Copyright © 2013 Massachusetts Medical Society. All rights reserved.

手術中の肺保護戦略が, 合併症を減らした.713年8月20日火曜日

無気肺, 肺炎, sepsis, 在院日数など減少.

Intr aoper ative Low-Tidal-Volume Ventilation

n engl j med 369;5 nejm.org august 1, 2013 435

have used either very low levels of PEEP or no PEEP.15,16,18 One strength of the present trial is our use of a robust composite outcome that is highly pertinent to this high-risk surgical population.5

Mechanical ventilation itself can induce an in-flammatory response30 and can synergize with the response induced by major surgery at both local and systemic levels. This amplification of

Table 3. Results of Unadjusted and Adjusted Outcome Analyses.*

Variable

NonprotectiveVentilation(N = 200)

Lung-Protective Ventilation(N = 200)

UnadjustedRelative Risk or Between-Group

Difference(95% CI) P Value†

AdjustedRelative Risk or Between-Group

Difference(95% CI)‡ P Value

Primary composite outcome — no. (%)

Within 7 days§ 55 (27.5) 21 (10.5) 0.38 (0.24–0.61) <0.001 0.40 (0.24–0.68) 0.001

Within 30 days 58 (29.0) 25 (12.5) 0.43 (0.28–0.66) <0.001 0.45 (0.28–0.73) <0.001

Secondary outcomes — no. (%)

Pulmonary complication within 7 days¶

Grade 1 or 2 30 (15.0) 25 (12.5) 0.69 (0.42–1.13) 0.14 0.67 (0.39–1.16) 0.16

Grade !3 42 (21.0) 10 (5.0) 0.24 (0.12–0.46) <0.001 0.23 (0.11–0.49) <0.001

Atelectasis within 7 days" 34 (17.0) 13 (6.5) 0.38 (0.21–0.70) 0.001 0.37 (0.19–0.73) 0.004

Pneumonia within 7 days 16 (8.0) 3 (1.5) 0.19 (0.05–0.63) 0.01 0.19 (0.05–0.66) 0.009

Acute lung injury or ARDS within 7 days 6 (3.0) 1 (0.5) 0.17 (0.02–1.37) 0.12 0.21 (0.02–1.71) 0.14

Need for ventilation within 7 days

Invasive 7 (3.5) 2 (1.0) 0.29 (0.06–1.36) 0.51 0.40 (0.08–1.97) 0.26

Noninvasive 29 (14.5) 9 (4.5) 0.31 (0.15–0.64) 0.006 0.29 (0.13–0.65) 0.002

Extrapulmonary complication within 7 days

SIRS 100 (50.0) 86 (43.0) 0.86 (0.70–1.06) 0.16 0.87 (0.65–1.17) 0.37

Sepsis 29 (14.5) 13 (6.5) 0.45 (0.24–0.84) 0.04 0.48 (0.25–0.93) 0.03

Severe sepsis or septic shock 9 (4.5) 8 (4.0) 0.89 (0.35–2.26) 0.80 1.48 (0.51–4.32) 0.47

Death within 30 days 7 (3.5) 6 (3.0) 0.86 (0.29–2.51) 0.80 1.13 (0.36–3.61) 0.83

Duration of stay in hospital and ICU — days

Hospital 0.02 0.006

Median 13 11 #2.25 (#4.04 to #0.47) #2.45 (#4.17 to #0.72)

Interquartile range 8–20 8–15

ICU 0.58 0.69

Median 7 6 #1.48 (#6.87 to 3.91) #1.21 (#4.98 to 7.40)

Interquartile range 4–9 4–8

* All postoperative complications were defined according to consensus criteria (see the Supplementary Appendix). For additional data on postoperative outcomes, see Tables S3 and S4 in the Supplementary Appendix. ARDS denotes acute respiratory distress syndrome, CI confi-dence interval, ICU intensive care unit, and SIRS systemic inflammatory response syndrome. Relative risks are shown for outcome variables, and differences between groups are shown for the duration of stays in the hospital and ICU.

† Adjustment was performed for stratification variables (use or nonuse of epidural analgesia and study center), preoperative risk index for postoperative pulmonary complications, sex, duration of surgery, and need for blood transfusion (yes or no).

‡ The Hochberg procedure was used to adjust for multiple testing of components of the composite primary outcome.27

§ The primary outcome was a composite of major pulmonary complications (defined as pneumonia or need for invasive or noninvasive ventilation for acute respiratory failure) and extrapulmonary complications (defined as sepsis, septic shock, or death) within the first 7 days after surgery.

¶ Postoperative pulmonary complications were scored with the use of a graded scale23 from 0 (no pulmonary complications) to 4 (the most severe complications) (see the Supplementary Appendix).

" Atelectasis was defined as opacification of the lung with shift of the mediastinum, hilum, or hemidiaphragm toward the affected area and compensatory overinflation in the adjacent, nonatelectatic lung.

The New England Journal of Medicine Downloaded from nejm.org at KOUSEIREN-HIROSHIMA-SOGO-BYOIN on August 2, 2013. For personal use only. No other uses without permission.

Copyright © 2013 Massachusetts Medical Society. All rights reserved.

Intr aoper ative Low-Tidal-Volume Ventilation

n engl j med 369;5 nejm.org august 1, 2013 435

have used either very low levels of PEEP or no PEEP.15,16,18 One strength of the present trial is our use of a robust composite outcome that is highly pertinent to this high-risk surgical population.5

Mechanical ventilation itself can induce an in-flammatory response30 and can synergize with the response induced by major surgery at both local and systemic levels. This amplification of

Table 3. Results of Unadjusted and Adjusted Outcome Analyses.*

Variable

NonprotectiveVentilation(N = 200)

Lung-Protective Ventilation(N = 200)

UnadjustedRelative Risk or Between-Group

Difference(95% CI) P Value†

AdjustedRelative Risk or Between-Group

Difference(95% CI)‡ P Value

Primary composite outcome — no. (%)

Within 7 days§ 55 (27.5) 21 (10.5) 0.38 (0.24–0.61) <0.001 0.40 (0.24–0.68) 0.001

Within 30 days 58 (29.0) 25 (12.5) 0.43 (0.28–0.66) <0.001 0.45 (0.28–0.73) <0.001

Secondary outcomes — no. (%)

Pulmonary complication within 7 days¶

Grade 1 or 2 30 (15.0) 25 (12.5) 0.69 (0.42–1.13) 0.14 0.67 (0.39–1.16) 0.16

Grade !3 42 (21.0) 10 (5.0) 0.24 (0.12–0.46) <0.001 0.23 (0.11–0.49) <0.001

Atelectasis within 7 days" 34 (17.0) 13 (6.5) 0.38 (0.21–0.70) 0.001 0.37 (0.19–0.73) 0.004

Pneumonia within 7 days 16 (8.0) 3 (1.5) 0.19 (0.05–0.63) 0.01 0.19 (0.05–0.66) 0.009

Acute lung injury or ARDS within 7 days 6 (3.0) 1 (0.5) 0.17 (0.02–1.37) 0.12 0.21 (0.02–1.71) 0.14

Need for ventilation within 7 days

Invasive 7 (3.5) 2 (1.0) 0.29 (0.06–1.36) 0.51 0.40 (0.08–1.97) 0.26

Noninvasive 29 (14.5) 9 (4.5) 0.31 (0.15–0.64) 0.006 0.29 (0.13–0.65) 0.002

Extrapulmonary complication within 7 days

SIRS 100 (50.0) 86 (43.0) 0.86 (0.70–1.06) 0.16 0.87 (0.65–1.17) 0.37

Sepsis 29 (14.5) 13 (6.5) 0.45 (0.24–0.84) 0.04 0.48 (0.25–0.93) 0.03

Severe sepsis or septic shock 9 (4.5) 8 (4.0) 0.89 (0.35–2.26) 0.80 1.48 (0.51–4.32) 0.47

Death within 30 days 7 (3.5) 6 (3.0) 0.86 (0.29–2.51) 0.80 1.13 (0.36–3.61) 0.83

Duration of stay in hospital and ICU — days

Hospital 0.02 0.006

Median 13 11 #2.25 (#4.04 to #0.47) #2.45 (#4.17 to #0.72)

Interquartile range 8–20 8–15

ICU 0.58 0.69

Median 7 6 #1.48 (#6.87 to 3.91) #1.21 (#4.98 to 7.40)

Interquartile range 4–9 4–8

* All postoperative complications were defined according to consensus criteria (see the Supplementary Appendix). For additional data on postoperative outcomes, see Tables S3 and S4 in the Supplementary Appendix. ARDS denotes acute respiratory distress syndrome, CI confi-dence interval, ICU intensive care unit, and SIRS systemic inflammatory response syndrome. Relative risks are shown for outcome variables, and differences between groups are shown for the duration of stays in the hospital and ICU.

† Adjustment was performed for stratification variables (use or nonuse of epidural analgesia and study center), preoperative risk index for postoperative pulmonary complications, sex, duration of surgery, and need for blood transfusion (yes or no).

‡ The Hochberg procedure was used to adjust for multiple testing of components of the composite primary outcome.27

§ The primary outcome was a composite of major pulmonary complications (defined as pneumonia or need for invasive or noninvasive ventilation for acute respiratory failure) and extrapulmonary complications (defined as sepsis, septic shock, or death) within the first 7 days after surgery.

¶ Postoperative pulmonary complications were scored with the use of a graded scale23 from 0 (no pulmonary complications) to 4 (the most severe complications) (see the Supplementary Appendix).

" Atelectasis was defined as opacification of the lung with shift of the mediastinum, hilum, or hemidiaphragm toward the affected area and compensatory overinflation in the adjacent, nonatelectatic lung.

The New England Journal of Medicine Downloaded from nejm.org at KOUSEIREN-HIROSHIMA-SOGO-BYOIN on August 2, 2013. For personal use only. No other uses without permission.

Copyright © 2013 Massachusetts Medical Society. All rights reserved.

ICU滞在日数や死亡率には差がなかった.813年8月20日火曜日

LTV + PEEP + RM

対象が, ある程度の高リスク患者.

低リスク患者では, これほどの差はないかもしれない.

低容量換気のほか, PEEPやRMも必要.

換気量制限が良いのか, No PEEPがいけないのか??

低すぎるPEEPは, 無気肺や肺合併症につながる.

RMは循環動態に影響を与える.

913年8月20日火曜日

この研究の強みと弱みStrengths

ハイリスク患者に関連の大きいアウトカムであること.

バイアスを最小限にしている（RCT, double-blind, ITT解析, complete follow-up）.

Limitations

輸液投与量を決めていない（結果的には, 両群間で差はなかった）.

対照群の非肺保護戦略の定義が普遍的なものではなく, 独自で決めた.

NPPV開始基準を決めていない（ガイドラインに基づいて診療を行っている）.

1013年8月20日火曜日

結論腹部手術中に肺保護戦略を行うことで, 術後の合併症を減らし, 入院日数を短縮した.

1113年8月20日火曜日