An innovative technique to improve safety of volatile anesthetics suction from the cardiopulmonary bypass circuit.

CONTEXT: Myocardial injury during cardiac surgery on cardiopulmonary bypass (CPB) is a major determinant of morbidity and mortality. Preclinical and clinical evidence of dose- and time-related cardioprotective effects of volatile anesthetic drugs exist and their use during the whole surgery duration could improve perioperative cardiac protection. Even if administering volatile agents during CPB are relatively easy, technical problems, such as waste gas scavenging, may prevent safe and manageable administration of halogenated vapors during CPB. AIMS: The aim of this study is to improve the safe administration of volatile anesthesia during CPB. SETTINGS AND DESIGN: Tertiary teaching hospital. SUBJECTS AND METHODS: We describe an original device that collects and disposes of any volatile anesthetic vapors present in the exit stream of the oxygenator, hence preventing its dispersal into the operating theatre environment and adaptively regulates pressure of oxygenator chamber in the CPB circuit. RESULTS: We have so far applied a prototype of this device in more than 1300 adult cardiac surgery patients who received volatile anesthetics during the CPB phase. CONCLUSIONS: Widespread implementation of scavenging system like the one we designed may facilitate the perfusionist and the anesthesiologist in delivering these cardioprotective drugs with beneficial impact on patients' outcome without compromising on safety.

Volatile anaesthetics added to cardiopulmonary bypass are associated with reduced cardiac troponin.

BACKGROUND: Every year, over 1 million cardiac surgical procedures are performed all over the world. Reducing myocardial necrosis could have strong implications in postoperative clinical outcomes. Volatile anaesthetics have cardiac protective properties in the perioperative period of cardiac surgery. However, little data exists on the administration of volatile agents during cardiopulmonary bypass. The aim of this study was to assess if volatile anaesthetics administration during cardiopulmonary bypass reduces cardiac troponin release after cardiac surgery. MATERIALS AND METHODS: We retrospectively analysed data from 942 patients who underwent cardiac surgery in a teaching hospital. The only difference between the groups was the management of anaesthesia during CPB. The volatile group received sevoflurane or desflurane while the control group received a combination of propofol infusion and fentanyl boluses. Patients who received volatile anaesthetics during cardiopulmonary bypass (n=314) were propensity-matched 1:2 with patients who did not receive volatile anaesthetics during CPB (n=628). RESULTS: We found a reduction in peak postoperative troponin I, from 7.8 ng/ml (4.8-13.1) in the non-volatile group to 6.8 ng/ml (3.7-11.8) in the volatile group (p=0.013), with no differences in mortality [2 (0.6%) in the volatile group and 2 (0.3%) in the non-volatile group (p=0.6)]. CONCLUSIONS: Adding volatile anaesthetics during cardiopulmonary bypass was associated with reduced peak postoperative troponin levels. Larger studies are required to confirm our data and to assess the effect of volatile agents on survival.

An innovative technique to improve safety of volatile anesthetics suction from the cardiopulmonary bypass circuit

CONTEXT: Myocardial injury during cardiac surgery on cardiopulmonary bypass (CPB) is a major determinant of morbidity and mortality. Preclinical and clinical evidence of dose- and time-related cardioprotective effects of volatile anesthetic drugs exist and their use during the whole surgery duration could improve perioperative cardiac protection. Even if administering volatile agents during CPB are relatively easy, technical problems, such as waste gas scavenging, may prevent safe and manageable administration of halogenated vapors during CPB. AIMS: The aim of this study is to improve the safe administration of volatile anesthesia during CPB. SETTINGS AND DESIGN: Tertiary teaching hospital. SUBJECTS AND METHODS: We describe an original device that collects and disposes of any volatile anesthetic vapors present in the exit stream of the oxygenator, hence preventing its dispersal into the operating theatre environment and adaptively regulates pressure of oxygenator chamber in the CPB circuit. RESULTS: We have so far applied a prototype of this device in more than 1300 adult cardiac surgery patients who received volatile anesthetics during the CPB phase...

Tricks, tips, and literature review on the adapted vaporize system to deliver volatile agents during cardiopulmonary bypass.

BACKGROUND: Recently, evidence of cardio-protection and reduction in mortality due to the use of volatile agents during cardiac surgery led to an increase in their use during cardiopulmonary bypass (CPB). These findings seem to be enhanced when the volatile agents are used during all the surgical procedure, including the CPB period. AIMS: Since the administration of volatile agents through CPB can be beneficial to the patients, we decided to review the use of volatile agents vaporized in the CPB circuit and to summarize some tricks and tips of this technique using our 10-year experience of Brazilian and Italian centers with a large volume of cardiac surgeries. STUDY SETTING: Hospital. METHODS: A literature review. RESULTS: During the use of the volatile agents in CPB, it is very important to analyze all gases that come in and go out of the membrane oxygenators. The proper monitoring of inhaled and exhaled fraction of the gas allows not only monitoring of anesthesia level, but also the detection of possible leakage in the circuit. Any volatile agent in the membrane oxygenator is supposed to pollute the operating theater. This is the major reason why proper scavenging systems are always necessary when this technique is used. CONCLUSION: While waiting for industry upgrades, we recommend that volatile agents should be used during CPB only by skilled perfusionists and physicians with the aim to reduce postoperative morbidity and mortality.

Use of volatile anesthetics during cardiopulmonary bypass: a systematic review of adverse events.

OBJECTIVES: Recently, evidence of reduction in mortality due to the use of volatile agents during cardiac surgery led to an increase in their use during cardiopulmonary bypass (CPB). Because this technique could be beneficial to patients, but might present several hazards to new users, the authors decided to perform a systematic review of the main problems and complications. DESIGN: Systematic literature review. SETTING: Hospital. PARTICIPANTS: Adults undergoing cardiac surgery with use of volatile anesthetic agents during CPB. INTERVENTION: Several databases were searched for pertinent studies to identify all reports on the adverse events of using volatile agents during CPB and all randomized controlled trials using volatile agents during CPB. MEASUREMENTS AND MAIN RESULTS: Six nonrandomized trials reporting adverse events or complications with the use of volatile agents during CPB for cardiac surgery were identified: 2 reporting low transfer of isoflurane to the blood with diffusion membrane oxygenators; 2 reporting iatrogenic causes of damage after spilling liquid isoflurane onto the surface of the membrane oxygenators while filling the vaporizer; and 2 suggesting that the use of volatile agents during CPB increased the pollution of the room and the risk of occupational exposure of the operating room staff. On the other hand, no adverse event was reported in 19 studies that randomized 1,195 patients to receive isoflurane, desflurane, or sevoflurane during CPB. CONCLUSION: It is mandatory for industry to provide safe and easy-to-use devices to administer volatile agents during CPB with the standard membrane oxygenators.