混合预充液吸入麻醉药液/气分配系数的推算值

目的 :测定晶体与胶体混合预充液的液 /气分配系数 ,比较液 /气分配系数的推算值与实测值。　　方法 :利用计算机编制程序 ,将乳酸林格液、琥珀酰明胶注射液 (佳乐施 )、库血和人体血浆 4种体外循环预充液排列组合后 ,随机抽取样本 10份 ,采用注射器 2次平衡法 ,利用气相色谱仪测定混合预充液在 37℃、33℃、2 9℃、2 5℃、2 1℃和17℃ 6个不同温度点的液 /气分配系数 ,并与推算值比较。　　结果 :混合预充液 3种吸入麻醉药的液 /气分配系数均与温度呈负相关 ,6个不同温度液 /气分配系数的推算值与实测值呈直线关系 (P<0 .0 5 ,地氟醚 r=0 .94,异氟烷 (异氟醚 ) r=0 .95 ,氟烷 r=0 .93)。　　结论 :由公式推算吸入麻醉药混合预充液的液 /气分配系数是可行的。     

血液稀释对麻醉药物作用影响的研究进展

血液稀释（HD）是围手术期血液保护的重要方法之一,近年来在外科手术中应用广泛,其优点显而易见,但血液稀释会引起机体一系列的生理变化,从而可能影响术中麻醉药物的作用。本文就不同血液稀释方法对各种麻醉药物作用的影响作一综述。     

Effects of droperidol on peripheral vasculature: use of cardiopulmonary bypass as a study model

The effects of droperidol on the systemic vascular resistance (SVR) and the venous capacitance were studied during cardiopulmonary bypass (CPB) in 24 patients. CPB was performed with either pulsatile or non-pulsatile flow. During non-pulsatile flow, droperidol (0.15 mg X kg-1 and 0.30 mg X kg-1) decreased SVR and increased venous capacitance. These values were significantly different after the 2nd and the 7th min, respectively. During pulsatile flow, the initial SVR was lower. The decremental effect of 0.30 mg X kg-1 droperidol on SVR was proportional to the preinjection level of SVR (r = 0.64). The increase in venous capacitance related to droperidol was independent of the dose and of the type of flow in all patients. It can be concluded that the vasodilating action of droperidol during CPB on the arterial bed is transient, independent of dose, and related to the preinjection level of SVR. The effect of droperidol on venous capacitance is not as rapid but has a longer duration.     

Comparative Efficacy of 2 Topical Anesthetics for the Placement of Orthodontic Temporary Anchorage Devices

This study compared the effectiveness of topical benzocaine 20% versus a combination of lidocaine, tetracaine, and phenylephrine in providing sufficient analgesia for the placement of orthodontic temporary anchorage devices (TADs). The 2 topical anesthetics were tested against each other bilaterally using a randomized, double-blind, crossover design. The agents were left in place for the amount of time prescribed by the manufacturer. The TAD was then placed, and each subject rated the degree of pain on a Heft-Parker visual analogue scale. A pulse oximeter was used to record the preoperative and postoperative pulse rates. Statistically significant differences in perceived pain (P < .05) and success rate (P < .01) between drugs were seen, but no significant difference in pulse rate change between the topical anesthetics was observed (P > .05). It was concluded that when the efficacy of topical benzocaine and of a combination product was compared as the sole anesthetic to facilitate acceptable pain control for placement of orthodontic temporary anchorage devices, the combination product was considerably more efficacious.     

Induction of anaesthesia

General anaesthesia is a temporary state of unconsciousness which is induced to facilitate a therapeutic procedure. Induction is the first stage of a sequential process. It commences with patient preparation and assessment away from theatre then continues in the safe and monitored environment of the anaesthetic room or operating theatre where the administration of drugs and airway interventions take place. The anaesthetic then transits through maintenance, emergence and recovery phases. The exact mechanism of induction, whether it be intravenous, inhalational or rapid sequence induction, depends on the needs of the patient and the procedure planned. As general anaesthesia is seldom a therapeutic intervention in itself, it is essential that inherent risks to the patient be minimized.     

Single-Injection Adductor Canal Block With Multiple Adjuvants Provides Equivalent Analgesia When Compared With Continuous Adductor Canal Blockade for Primary Total Knee Arthroplasty: A Double-Blinded,Randomized, Controlled,Equivalency Trial

Background

Peripheral nerve blockade is used to provide analgesia for patients undergoing total knee arthroplasty. This study compared a single-injection adductor canal block (SACB) with adjuvants to continuous adductor canal blockade (CACB). The hypothesis was that the 2 groups would have equivalent analgesia at 30 hours after neural blockade.

Observations on use of wrong agent in an anesthesia agent vaporizer

The creation of agent mixtures from the addition of the wrong agent to a vaporizer might pose a risk to the patient. Patient injury would be more likely if the anesthesia gas monitor displayed erroneous concentration values. Conventional inhalation agent monitors do not necessarily distinguish anesthetic agents. Some modern monitors have that ability but its clinical significance has not been determined. We wanted to simulate such an erroneous mixture in a laboratory setup. Six comparisons were made. Isoflurane, Enflurane, and Halothane vaporizers were first filled with the correct agent. They were run at 5 liters/minute fresh oxygen flow at a vaporizer dial setting of 5% until it reached the refill line. Then, one of two incorrect agents was added to the full line. Thereafter, the vaporizer continued at the same flow and the same dial setting until it was exhausted. Vaporizer output was recorded or calculated by using three methods of measurement: mass spectrometry, conventional infrared analysis (at 3.3 micrometer wave length), and piezoelectric crystal analysis. Additional calculations were used to estimate measurements that could not be made because of lack of available equipment. In a Halothane vaporizer: Enflurane added – not a significant problem; Isoflurane added – not a significant problem. In an Isoflurane vaporizer: Halothane added – not a significant problem; Enflurane added – not a significant problem. In an Enflurane vaporizer: Isoflurane added – not a significant problem; Halothane added – The sum of the delivered Halothane MAC and the delivered Enflurane MAC was twice the expected Enflurane MAC output from vaporizer, with conventional agent monitor reading which showed decreasing agent concentration. Patient injury could be more likely in this last case. In this last case and in all cases, piezoelectric crystal monitoring correctly displayed the sum of the two agent concentrations in volumes percent. Automatic agent identification can identify erroneous agents.     

Manutenção da anestesia inalatória com a máscara facial Janus para substituição de válvula aórtica transcateter: uma série de casos

Background and objectives

Aortic stenosis is the most common type of heart valve disease. Percutaneous aortic valve replacement has become the alternative for patients considered at high risk for surgery. Controlled mechanical ventilation with tracheal intubation has been the choice for this type of procedure, however the use of noninvasive ventilation in cardiac patients has shown to be beneficial. Janus is a novel full‐face mask that allows application of noninvasive ventilation support during anesthesia. Our main objective was to evaluate the feasibility of transcatheter aortic valve replacement with prolonged transesophageal echocardiographic monitoring under deep inhalational sedation delivered through a new mask for noninvasive ventilation.

Riscos ocupacionais,danos no material genético e estresse oxidativo frente à exposição aos resíduos de gases anestésicos

Background and objectives

The waste anesthetic gases (WAGs) present in the ambient air of operating rooms (OR), are associated with various occupational hazards. This paper intends to discuss occupational exposure to WAGs and its impact on exposed professionals, with emphasis on genetic damage and oxidative stress.