The field of respiratory physiology covers a wide range of research topics such as the studies on pulmonary ventilation, gas exchange in the lungs, the transport of gases by the blood, and the mechanism of tissue metabolism. The great advances achieved after the 20 century have solved many problems related to alveolar gas exchange or alveolar ventilation. Respiratory management is the most specialized area in clinical practice for anesthesiologists and the anesthesiologists are required to have basic knowledge of alveolar ventilation. To clearly understand alveolar ventilation, it is necessary to understand both the control of breathing and the function of respiratory system as a gas exchange organ. Furthermore, to understand the clinical pathology of respiration, it is important to understand the effects of general anesthesia and narcotics on the control of breathing, as well as the factors influencing maldistribution of ventilation, abnormal ventilation/perfusion ratio, and increases in pulmonary shunt.

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 Local anesthetics prevent and relieve pain by interfering with conduction of action potentials in the nervous system by direct interaction with voltage-dependent sodium channels. Recently, a three-dimensional structure of α-subunit of the voltage-dependent sodium channel has been revealed. Also, at least nine subtypes of voltage-dependent sodium channels have been identified. The elucidation of the voltage-dependent sodium channel appears to provide new insights into the mechanism of action of the local anesthetics and the pathophysiology of intractable pain.

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 The administration of local anesthetics carries the potential hazard of producing central nervous system and cardiovascular toxicity. Severe cardiovascular toxicity can occur when bupivacaine is accidentally injected intravascularly, leading to fatal dysrhythmia and cardiac arrest. Bupivacaine-induced cardiovascular toxicity is resistant to conventional treatment, and resuscitation is difficult. Recently, lipid therapy, using an infusion of lipid emulsion, has been reported to be effective for the resuscitation of bupivacaine-induced cardiovascular toxicity. Ropivacaine and levobupivacaine were developed as new long-acting amide local anesthetics with less cardiovascular toxicity. They consist of pure levorotatory S-enantiomers. In an experimental study in rats, we found that the cumulative dose inducing cardiac arrest was greater for ropivacaine than for bupivacaine and levobupivacaine. We also found that ropivacaine-induced cardiac arrest was more responsive to treatment than that induced by bupivacaine or levobupivacaine. Although ropivacaine has a greater margin of safety between the doses required to induce seizures and cardiac arrest, several cases of ropivacaine-induced cardiac arrest have been reported. Therefore, attention should be paid to the potential hazards of ropivacaine in clinical practice.

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 Epidural analgesia has long been an important technique for post operative pain relief in this country. However, the indication for or practice of epidural analgesia has recently been changing because new drugs, such as the antiplatelet agent fondaparinux, or the opioid analgesic remifentanil are being used more. Administration of fondaparinux to prevent perioperative pulmonary artery embolism strictly limits the indication of epidural analgesia. Concerning remifentanil, whose analgesic effect rapidly disappears upon its discontinuation, its use can make postoperative pain relief more complicated. Even under remifentanil use, we believe that epidural analgesia can provide pain relief of higher quality. In this article, we review the usefulness of epidural analgesia for postoperative pain relief compared with that of intravenous opioid infusion, and we evaluate three practices of epidural analgesia to obtain higher-quality of postoperative pain relief in patients undergoing general anesthesia with remifentanil.

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 One of the features of obstetric practice is the high frequency of emergent conditions. Facing with nonreassuring fetal status, especially prolonged deceleration, speedy delivery of the fetus is essential for preventing not only fetal demise but also neurologic sequela. Placenta accreta/increta, which is relatively difficult to diagnose, is a serious condition necessitating a multidisciplinary approach. In order to avoid unexpected profuse bleeding, after delivering the baby, leave the placenta alone, and hysterectomy can be performed safely with the use of transcatheter arterial embolization/balloon occlusion. In addition to feto/maternal emergencies, the anesthesiologist should be consulted in surgery during pregnancy, fetal surgery, critical care, labor analgesia, etc. Close collaboration with the anesthesiologist is indispensable for safe maternal and fetal management.

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 Perinatal medicine is becoming more centralized as general opinion changes and the public recognizes the improved safety offered by larger institutions. Anesthesiologists can play a more important part in perinatal emergencies, as the centralization of perinatal medicine continues and public opinion matures. Perinatal emergencies are divided into two categories: maternal emergencies and fetal emergencies. Maternal emergencies encompass seizures, embolism and massive obstetric hemorrhage such as placental abruption, placenta previa and uterine inversion. Fetal emergencies are almost always ultra-emergency cesarean sections. We describe our experiences of perinatal emergencies in Seirei Hamamatsu General Hospital, and discuss the role of obstetric anesthesiologists.

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 Over the past 10 years, I have experienced approximately 3,000 epidural births.
 Obstetricians strive for ideal childbirth in all deliveries that they undertake, namely an extremely short delivery time, a smooth delivery from start to finish, minimal discomfort for the laboring mother, a healthy newborn, minimal postpartum bleeding, and a quick recovery after delivery.
 As an obstetrician in private practice for 22 years using internal direct monitoring for delivery, I have arrived at the conclusion that the epidural birth is extremely effective in achieving an ideal delivery. I have been able to achieve a sympathetic agreement with the mother, whereby the pregnancy is safe, peaceful, and pleasant, and the mother says to me “If this is what delivery is all about, then I will come here to deliver again!”
 The epidural birth is effective in keeping healthy, not distorting, the extreme beginning of childrearing.
 Below, I state my points of caution as a private-practice obstetrician whose medical practice lacks significant manpower.

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 I carried out a retrospective assessment of epidural analgesia in 3,439 parturients. Among them, 2,599 women had epidural analgesia for vaginal delivery. Most epidural insertions were performed according to own protocols. Only 52.3% had an uncomplicated and successful first epidural analgesia. The other 47.7% had inadequate pain relief upon the first epidural injection and late in labor, and required supplemental epidural medications. The data suggest that the effectiveness of the first epidural injection and of the late injection in labor should be determined by informed maternal satisfaction.

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 Infants with congenital diaphragmatic hernia (CDH) have pulmonary hypoplasia resulting in persistent neonatal pulmonary hypertension, a predominant contributor to both high mortality and morbidity. The pulmonary artery bed in patients with CDH is underdeveloped and is very sensitive to even the slightest stimuli. Therefore, it is vital to avoid any factors that might increase pulmonary vascular resistance during perinatal treatment.
 We experienced nine cases of anesthesia for cesarean section in patients with prenatally diagnosed CDH. Remifentanil/propofol anesthesia was selected for fetal sedation at birth. The newborn was intubated immediately following birth and ventilated with high frequency oscillation co-administered nitric oxide. Spontaneous breathing and movement of the newborns were restrained in all cases by the transition of remifentanil through the placenta. Remifentanil facilitated neonatal intubation and preoperative general management for newborns with CDH.

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 We studied the success rates of tracheal intubation using the gum-elastic bougie in simulated difficult intubation. After induction of anaesthesia, the patient's head was fixed using manual in-line stabilization. A laryngoscopic view assessment was made using conventional Macintosh laryngoscopy as described by Cormack and Lehane. We then attempted tracheal intubation using a gum-elastic bougie. The tube was correctly placed in the trachea in 100% cases of grade 2a and 2b, in 90% of grade 3a, 51% of grade 3b and 0% of grade 4.

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 A 22-year-old man experienced frequent swelling of the left arm. Further examination revealed a blood clot in the left subclavian vein, which was diagnosed as thoracic outlet syndrome. We started treatment with intravenous thrombolytics followed by oral anticoagulation agents. Because of the recurrence of thromboembolism, we planned a radical cure and performed resection of the first rib. During the perioperative period, we faced difficulty in judging the best method to prevent venous thromboembolism. Finally, the patient was discharged from the hospital without any perioperative complications. Japanese Guidelines for Prevention of Venous Thromboembolism do not mention any measures for secondary prevention of thrombosis during the perioperative episode of thromboembolism. Further studies are necessary in the future in this regard.

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 A 48-year-old female was scheduled for laparoscopic hysterectomy. Following induction of pneumoperitoneum using carbon dioxide (CO₂) , end-tidal partial pressure of CO₂ (PETCO₂) gradually increased to 60 mmHg, and was accompanied by the temporary appearance of negative T-waves and RS pattern in the II - and III - leads of the electrocardiogram (ECG) . These ECG changes disappeared after PETCO₂ returned to approximately 40 mmHg.
 When peritoneal insufflation of CO₂ was initiated again, massive subcutaneous emphysema extending from the left thorax to the face was noticed. At this time, the same ECG changes were observed at the PETCO₂ of 40 mmHg.
 These observations raise the possibility that negative T-wave and RS pattern in the II - and III - leads of ECG appeared as a sign of complications of subcutaneous emphysema in the thorax. We conclude that subcutaneous emphysema can modulate the ECG during laparoscopy even in the absence of hypercarbia.

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 Among those patients with cerebral infarction who were brought to our emergency department from December 2005 through June 2007, 28 satisfied the criteria for indication for alteplase, recombinant tissue plasminogen activator (rt-PA) , and served as the subjects of this study. According to the treatment protocol that our group, led by neurologists, had prepared, 0. 6 mg/kg of rt-PA was administered following a CT of the head region that negated the presence of a brain hemorrhage. The time that elapsed between onset and rt-PA administration was 41-167 minutes (median 95) . For 24 hours after medication, the patients were placed under respiratory and circulatory care and their neurological performances were observed in an ICU or a neurological ward. On a modified ranking scale, which indicates the possibility for social rehabilitation, 9 patients (32%) were rated to be between 0 to 1. Four (14%) succumbed during this period. By formulating a treatment protocol, rapid administration of rt-PA and monitoring to prevent complications became possible.

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 A 59-year-old woman with chronic renal failure and hypertension was scheduled to undergo resection of hepatic tumor. During manipulation of the tumor, repeated unusual hypertension was shown, so we suspected pheochromocytoma and terminated the operation. Upon multiple examinations after the surgery, she was diagnosed as having paraganglioma. Adrenergic alpha-blockers were used as preoperative circulation control. After her blood pressure was controlled, she underwent resection of paraganglioma again. During the second operation, the management of her blood pressure was easier and safer than during the first operation, and no complications occurred.

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 The history of the development of neuromuscular blocking agents is that it was found that a nondepolarizing agent that could replace suxamethonium chloride, a depolarizing agent, for rapid onset of action. In Japan, a new aminosteroidal neuromuscular blocking agent, rocuronium bromide, has recently been introduced into clinical practice. Its advantage over other currently used nondepolarizing agents is a fast onset of action similar to suxamethonium. Regarding the duration of action, rocuronium is similar to vecuronium, so that anesthesiologists can easily switch vecuronium to rocuronium during maintenance of anesthesia. Due to a low potency and low concentration of metabolites, rocuronium metabolites are very unlikely to contribute to the muscular blocking effects of the parent compound during long continuous infusion.

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 Rocuronium, a desacetoxy derivate of vecuronium, shares the intermediate duration of action with vecuronium. However, the onset of action of rocuronium is considerably faster than vecuronium. Recommended dose for endotracheal intubation is 0.6 mg/kg (2 X ED₉₅) , which completely inhibits muscle twitches in about 90 seconds. However, higher doses should be used for rapid sequence intubation. Following 1 mg/kg of rocuronium, good to excellent conditions for endotracheal intubation are obtained within 60 seconds. Overall, intubating conditions with high-dose rocuronium are similar when compared with those of suxamethonium. Priming principle is clinically used more to shorten the onset of rocuronium. However, the optimal priming and intubating doses of rocuronium have not been clearly elucidated, and even a small priming dose causes rocuronium injection pain when used in awake patients. Timing principle using high-dose rocuronium is also a useful method for rapid sequence intubation. For laryngeal mask insertion, very low-dose (0.1-0.3 mg/kg) rocuronium is effective. It is important for anesthesiologists to know how to adjust the dose of rocuronium and to know how to administer rocuronium upon considering patient's conditions and varieties of anesthesia.

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 Rocuronium blomide is a steroidal neuromuscular blocking agent with rapid onset and intermediate duration and a neuromuscular blockade that is potentiated by volatile anesthetics. Postoperative residual curarization is a potentially lethal complication of anesthesia and its presence has been confirmed by some studies even when intermediate neuromuscular blocking agents have been used. Residual neuromuscular blockade can be antagonized by anticholinesterases, but these have their own side effects, such as bradycardia, postoperative nausea and vomiting. This, in turn, requires cholinergic antagonists. Caution should be taken for the timing of reversal agents and quantitative evaluation is recommended to avoid residual paralysis in postanesthetic care unit. The train-of-four ratio (TOFR) at the adductor pollicis required to avoid residual paralysis is now considered to be at least 0.9.
 Sugammadex is a modified cyclodextrin designed to encapsulate aminosteroidal non-depolarizing muscle relaxants within its lipophilic core which is no longer available to bind with the acetylcholine receptor. It has been shown to be safe and effective in humans. Its rapid reversal of blockade makes it possible to keep patients profoundly muscle-relaxed during the induction and maintenance of anesthesia, and it can improve patient safety.

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 Rocuronium has no metabolites and little cumulative effect, and the recovery time from block is constant. Therefore, rocuronium can be easily adjusted for the long operations required in neurosurgery and spinal surgery. It easily stabilizes conditions in partial neuromuscular blockade during intraoperative neurologic monitoring such as motor evoked potentials. Because rocuronium has rapid onset, it may be use for rapid sequence induction of anesthesia.

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 Cardiac/aortic surgery can dramatically change physiological parameters such as respiration, circulation, body temperature, and electrolyte level. Although the surgery per se is invasive, fast-track anesthesia, which could lead to benefits for patients, is needed. Rocuronium has a rapid onset, and thus it would be useful to prevent opioid-induced muscle rigidity. Because the main metabolite of rocuronium has few muscle-relaxant effects, unexpected prolonged muscle relaxation is rare after surgery. Rocuronium is, therefore, expected to be safe and useful in cardiac/aortic surgery as well as other kinds of surgery. It is needless to say that we should pay attention to the potency of rocuronium during cardiac/aortic surgery, because the potency and the metabolism of it can be changed by hypothermia, hemodilution, and electrolyte abnormalities, as well as by complicated organ failure.

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 Rocuronium is rapidly taken up in the liver and the majority of it is excreted into the bile, with relatively little going into the urine. The duration of action of rocuronium is not altered or prolonged in patients with renal failure, but is consistently prolonged in patients with liver disease. In the case of liver transplantation, increases in rocuronium plasma concentrations and prolongation in recovery time from rocuronium-induced neuromuscular block during the neohepatic phase suggest impaired organ function after reperfusion of the graft liver. Rocuronium should be used with caution in patients with renal failure or liver disease who underwent liver transplantation surgery. Monitoring of neuromuscular block in these groups of patients is essential.

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 Changes in functions of neuromuscular junctions induced by neuromuscular or muscular disorder influence actions of rocuronium and other non-depolarizing neuromuscular blockers. In myasthenia gravis and Lambert-Eaton syndrome, the action of rocuronium is reinforced due to dysfunction of neuromuscular transmission. Action of rocuronium is often enhanced in Duchenne-type muscular dystrophy and myotonic dystrophy, myopathies that impair not only the function of muscle fibers but also the function of neuromuscular junctions. Sepsis often attenuates the action of rocuronium by modulating the function of neuromuscular junctions.

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 Because fast onset and metabolic product do not have pharmacological action, rocuronium is easy to use. However, due to electrolyte disorders or drug interaction, action augmentation or antagonism of neuromuscular blocking agents (NMBAs) may cause unanticipated reactions. Moreover, it is necessary to well understand the pharmacokinetics and pharmacodynamics of rocuronium in hypothermia. When NMBAs are used in the Intensive Care Unit (ICU) compared with in an operating room, it is very likely used for a long time. In addition, we should consider protracted bed rest, drug interactions, underlying diseases, pharmacokinetics and pharmacodynamics. This part comments on a continuous infusion of rocuronium in the ICU, and the pit-falls influencing the fast track of cardiac surgery using rocuronium.

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