Effect of age on pulmonary gas exchange during laparoscopy in the Trendelenburg lithotomy position.

BACKGROUND: Physiological changes in respiratory mechanics caused by aging may lead to a deterioration in pulmonary gas exchange, an increase in the alveolar-arterial oxygen gradient [(A-a)D(O2)] and a difference between the arterial carbon dioxide (CO(2)) tension (P(a)(CO(2))) and expired end-tidal CO(2) tension (P(ET)(CO(2))) [P((a-ET))(CO(2))] during laparoscopy in the Trendelenburg lithotomy position (TLP). METHODS: The subjects were 51 gynecologic patients. Pressure-controlled ventilation was used to maintain P(ET)(CO(2)), measured by the side stream method, within the range 4-4.67 kPa. During laparoscopy with CO(2) insufflation in TLP, the tidal volume was increased to keep P(ET)(CO(2)) within +/- 20% of the pre-insufflation value. The subjects were divided into three groups by age: young group (< 45 years); middle-aged group (45-64 years); and elderly group ( > or = 65 years). RESULTS: Before pneumoperitoneum (PPN), significant differences were found between the young and elderly groups in the arterial oxygen tension (P(a)(O(2))), (A-a)D(O(2)), P(a)(CO(2)) and P((a-ET))(CO(2)). In all groups, the peak inspiratory pressure and P(a)(CO(2)) increased progressively during PPN in TLP. P((a-ET))(CO(2)) increased gradually after starting CO(2) insufflation in TLP only in the elderly group. CONCLUSIONS: An increase in P((a-ET))(CO(2)) was seen during PPN in TLP in the elderly group. With CO(2) insufflation in TLP, the setting of mechanical ventilation based on the value of P(ET)(CO(2)) (measured by the side stream method) should be determined with caution in elderly patients.

Arytenoid cartilage dislocation caused by a double-lumen endobronchial tube.

Following surgery requiring the use of a double-lumen endobronchial tube, a patient immediately complained of persistent severe hoarseness. On the third day after the operation, fibreoptic laryngoscopy revealed posterolateral dislocation of the left arytenoid cartilage. By the sixth day of the operation, a slight improvement was observed in the hoarseness without treatment and a spontaneous recovery of arytenoid cartilage dislocation was expected. The patient did not consent to surgical treatment, and therefore a conservative therapy was selected. Ten weeks after the operation, it was found that the dislocated left arytenoid cartilage had spontaneously repositioned and the patient regained his normal voice. The causes and treatment options are discussed.

[Effects of lumbar sympathetic ganglion block in a patient with acquired lymphangioma].

A 70-year-old woman developed lymphangioma following surgery for cervical cancer and subsequent radiotherapy. The operation was performed 12 years ago, and a swelling of lower extremities was recognized 8 years ago. Her lower extremities became greatly edematous, and leakage of lymph to the groin was observed. We performed bilateral lumbar sympathetic ganglion block. After the block, lymphedema was relieved dramatically, and the leakage of the lymph to the groin was gradually reduced. We conclude that lumbar sympathetic ganglion block may be very effective in some patients with acquired lymphangioma.

[Anesthetic management in a patient with Simpson-Golabi-Behmel syndrome].

We report the anesthetic management of a 4-yr-old boy with Simpson-Golabi-Behmel syndrome. This syndrome is an X-linked condition characterized by pre- and postnatal overgrowth with visceral and skeletal anomalies. Affected males have a distinctive facial appearance with wide nasal bridge, anteverted nostrils, wide-open mouth, enlarged tongue, and large protruding maxilla and jaw. Although it had been speculated preoperatively that airway management would be complicated by the macroglossia, there was no difficulty in endotracheal intubation in the present patient. Preparations for difficult airway management should be made by the anesthesiologist before induction of anesthesia.

Roles of prostaglandin I(2) and thromboxane A(2) in cardiac ischemia-reperfusion injury: a study using mice lacking their respective receptors.

BACKGROUND: Prostaglandin (PG) I(2) and thromboxane (TX) A(2), the most common prostanoids in the cardiovascular system, are produced abundantly during cardiac ischemia/reperfusion (I/R); their roles in I/R injury, however, remain undetermined. We intended to clarify these roles of PGI(2) and TXA(2) using mice lacking the PGI(2) receptor, IP(-/-) mice, or the TXA(2) receptor, TP(-/-) mice. METHODS AND RESULTS: The left anterior descending coronary artery was occluded for 1 hour and then reperfused for 24 hours. The size of myocardial infarct in IP(-/-) mice was significantly larger than that in wild-type mice, although the size of the area at risk was similar between the 2 groups of mice. In contrast, there was no such difference between TP(-/-) and wild-type mice. To further determine whether PGI(2) and TXA(2) act directly on the cardiac tissue or indirectly through their action on blood constituents, we perfused excised heart according to the Langendorff technique. The isolated heart was then subjected to global ischemia followed by reperfusion. In IP(-/-) mice, developed tension and coronary flow rate during reperfusion were significantly lower and release of creatine kinase was significantly higher than those in wild-type mice. There were no such differences, however, between TP(-/-) and wild-type mice. CONCLUSIONS: PGI(2), which was produced endogenously during cardiac I/R, exerts a protective effect on cardiomyocytes independent of its effects on platelets and neutrophils. In contrast, TXA(2) has little role in the cardiac I/R injury.

Increased bleeding tendency and decreased susceptibility to thromboembolism in mice lacking the prostaglandin E receptor subtype EP(3).

BACKGROUND: Among the prostanoids, thromboxane (TX) A(2) is a potent stimulator of platelets, whereas prostaglandin (PG) I(2) inhibits their activation. The roles of PGE(2) in the regulation of platelet function have not been established, however, and the contribution of PGE(2) in hemostasis and thromboembolism is poorly understood. The present study was intended to clarify these roles of PGE(2) by using mice lacking the PGE(2) receptor subtype 3 (EP(3)(-/-) mice). METHODS AND RESULTS: Expression of mRNAs for EP(3) in murine platelets was confirmed by quantitative reverse transcription-polymerase chain reaction. PGE(2) and AE-248, a selective EP(3) agonist, showed concentration-dependent potentiation of platelet aggregation induced by U46619, a TXA(2) receptor agonist, although PGE(2) alone could not induce aggregation. PGE(2) and AE-248 increased cytosolic calcium ion concentration ([Ca(2+)](i)), and AE-248 inhibited the forskolin-induced increase in cytosolic cAMP concentration ([cAMP](i)), suggesting G(i) coupling of EP(3). The potentiating effects of PGE(2) and AE-248 on platelet aggregation along with their effects on [Ca(2+)](i) and [cAMP](i) were absent in EP(3)(-/-) mice. In vivo, the bleeding time was significantly prolonged in EP(3)(-/-) mice. Moreover, when mice were challenged intravenously with arachidonic acid, mortality and thrombus formation in the lung were significantly reduced in EP(3)(-/-) mice. CONCLUSIONS: - PGE(2) potentiated platelet aggregation induced by U46619 via EP(3) by increasing [Ca(2+)](i), decreasing [cAMP](i), or both. This potentiating action of PGE(2) via EP(3) is essential in mediating both physiological and pathological effects of PGE(2) in vivo.

[Anesthetic management of a patient with a giant bulla and liver cirrhosis using a laryngeal mask airway and epidural analgesia].

A laryngeal mask airway (LMA) and epidural analgesia were used for anesthetic management of microwave coagulo-necrotic therapy for multiple hepatoma in a 76-year-old male with a giant bulla and liver cirrhosis. Since bleeding times, PT and APTT were within normal limits, an epidural catheter was inserted between Th9 and 10 interspaces in operating room. After preoxygenation, general anesthesia was induced with propofol 120 mg. After insertion of a LMA, anesthesia was maintained under spontaneous breathing with sevoflurane (1-1.5%) in about 45% oxygen and nitrogen. During the operation, 2% lidocaine was injected continuously into the epidural space. Continuous epidural injection of 2% lidocaine was found to be very effective for obtaining abdominal muscle relaxation and perioperative pain management. Postoperative chest X ray did not show any signs of rupture of the giant bulla, and any neurological abnormalities due to the epidural hematoma were not encountered. We could reduce the risk of rupture of a giant bulla during general anesthesia using a LMA and epidural analgesia.

[Intracerebral hemorrhage induced by cerebral amyloid angiopathy in a patient during transurethral electrocoagulation].

A 68-year-old female with severe anemia due to a bleeding bladder was scheduled for emergency transurethral electrocoagulation surgery under general anesthesia. Her preoperative consciousness was clear. After preoxygenation, general anesthesia was induced with ketamine 40 mg and vecuronium 6 mg. After tracheal intubation, anesthesia was maintained with nitrous oxide, oxygen, and isoflurane (0.5-0.8%). During the operation, a large fluctuation in blood pressure was observed. The operation was completed uneventfully, but the patient did not recover smoothly from the anesthesia. A few minutes later, signs of neurological abnormality were observed, and an emergency brain CT scan was performed. Since CT images of the brain showed extensive intracerebral hemorrhage (ICH) and edema, emergency craniotomy was performed. Postoperative pathological examination showed that the cause of the ICH was cerebral amyloid angiopathy (CAA). Since the incidence of CAA is relatively high in elderly people and CAA can cause ICH due to fluctuation in blood pressure, prudent anesthetic management is needed for elderly patients undergoing emergency operations, particularly an operation leading to a decrease in blood volume.

[Perioperative management using propofol in a patient with uncontrolled preoperative hyperthyroidism].

There is a risk of thyrotoxic crisis during and after surgery in patients with uncontrolled hyperthyroidism. To avoid this, suppression of sympathetic activity during the perioperative period is important. For this purpose, we used propofol for the anesthetic and the postoperative management in a 19-year-old female with uncontrolled hyperthyroidism. Propofol 6 to 8 mg.kg-1.hr-1 plus 66% of nitrous oxide was not sufficient to obtain hemodynamic stability during the surgery, but propofol 3 mg.kg-1.hr-1 produced optimal sedation in the postoperative period. The results demonstrate that propofol is useful for the anesthetic management of patients with uncontrolled hyperthyroidism.

Cesarean section in a patient with syringomyelia.

PURPOSE: To describe the anesthetic management of Cesarean section in a patient with syringomyelia. CLINICAL FEATURES: A 27-yr-old pregnant woman with syringomyelia was scheduled to undergo elective Cesarean section. At the age of 25 yr, she had begun to experience headaches, and at the age of 26 yr, a diagnosis of syringomyelia of the upper spinal cord was made on the basis of magnetic resonance imaging findings. No symptoms other than headache were noted preoperatively. General anesthesia was used for the Cesarean section. After the administration of 1 mg vecuronium as a priming dose, 5 mg vecuronium were injected. At the onset of clinical muscle weakness, 225 mg thiamylal were promptly administered as the induction agent and the patient was intubated (timing principle with priming method) and pressure on the cricoid cartilage applied to prevent regurgitation of stomach contents. Anesthesia was maintained with oxygen, nitrous oxide and isoflurane at a low concentration. Mild hyperventilation was used throughout the procedure. Anesthesia and surgery proceeded without any problem, response to vecuronium was clinically normal and recovery was uneventful. Neurological status remained normal. CONCLUSION: We report the safe use of general anesthesia for Cesarean section in a patient with syringomyelia. Precautions were taken to avoid increases in intracranial pressure and our patient experienced no untoward neurologic event.

[A survey of 3,303 6th-year medical students from 36 universities concerning knowledge of resuscitation--more than 80% of medical students can not perform standard cardiopulmonary resuscitation?].

Questionnaires on knowledge of resuscitation were distributed to 3,303 6th-year medical school students from 36 universities. The questionnaire included 13 questions based on the 1992 guidelines for cardiopulmonary resuscitation. From the 13 questions, each student was instructed to select 6 questions concerning assessment of consciousness level, method for confirming respiration, method for securing the airway, method for confirming circulation, pressure points for cardiac massage, and the ratio of respiration and cardiac massage. If all of these six questions could not be answered correctly, it was considered that the student was not able to perform resuscitation according to the guidelines. At least one incorrect answer was given to the six questions by 84% of students, indicating that most medical students are not able to actually perform standard resuscitation. Possible reasons for these results may be the lack of desire on the part of students to master resuscitation, confusion over new findings concerning resuscitation and guideline, insufficient understanding of the difference between the guidelines and new findings by educators, and restricted teaching time for resuscitation. Possible ways to improve the situation include efforts to make students more responsible to master resuscitation, efforts to enhance students' desire to learn, adoption of more practical education, inclusion of such questions in graduation examinations and the national examination for a medical license, adherence by educators to the guidelines, and efforts by educators to make a clear distinction between the guidelines and new findings. With new guidelines for cardiopulmonary resuscitation due out in the year 2000, methods for teaching resuscitation should be reconsidered in order to ensure that all medical students can competently perform resuscitation.

[Anesthetic management of two patients with insulinoma using propofol--in association with rapid radioimmunoassay for insulin].

We experienced anesthetic management of two patients with insulinoma in whom frequent hypoglycemic episodes with blood glucose levels of 39-42 mg.dl-1 had been observed. Each patient received epidural analgesia with a catheter inserted at the T 9/10 intervertebral space. Anesthesia was induced with propofol 80-100 mg and fentanyl 200 micrograms. Tracheal intubation was facilitated with vecuronium 6 mg. Anesthesia was maintained with continuous infusion of propofol and epidural anesthesia. Rapid measurements of immunoreactive insulin (IRI) were useful for localization of insulinoma during surgery. Perioperative plasma glucose levels could be maintained within normal ranges by continuous infusion of glucose. Rebound hyperglycemic episodes were not observed, and IRI was reduced after removal of the insulinoma. General anesthesia using propofol and epidural block is a useful choice for the anesthetic management of patients undergoing an operation for removal of an insulinoma.

Antinociceptive interaction between spinal clonidine and lidocaine in the rat formalin test: an isobolographic analysis.

UNLABELLED: Clinical and basic science studies suggest that spinal alpha-2-adrenergic receptor agonists and local anesthetics produce analgesia, but interaction between alpha-2-adrenergic receptor agonists and local anesthetics in the persistent pain model has not been examined. In the present study, using isobolographic analysis, we investigated the antinociceptive interaction of intrathecal clonidine and lidocaine in the rat formalin test. Sprague-Dawley rats were implanted with chronic lumbar intrathecal catheters, and were tested for paw flinch by formalin injection. Biphasic painful behavior was counted. Intrathecal clonidine (3-12 nmol) was administered 15 min before formalin, and intrathecal lidocaine (375-1850 nmol) was administered 5 min before formalin. To examine the interaction of intrathecal clonidine and lidocaine, an isobolographic design was used. Spinal administration of clonidine produced dose-dependent suppression of the biphasic responses in the formalin test. Spinal lidocaine resulted in dose-dependent transient motor dysfunction and the motor dysfunction recovered to normal at 10-15 min after administration. Spinal lidocaine produced dose-dependent suppression of phase-2 activity in the formalin test. Isobolographic analysis showed that the combination of intrathecal clonidine and lidocaine synergistically reduced Phase-2 activity. We conclude that intrathecal clonidine synergistically interacts with lidocaine in reducing the nociceptive response in the formalin test. IMPLICATIONS: Preformalin administration of intrathecal clonidine and lidocaine dose-dependently produced antinociception in the formalin test. The combination of clonidine and lidocaine, synergistically produced suppression of nociceptive response in the persistent pain model.

[Anesthetic management for thoracoscopic bullae resection using epidural anesthesia].

We report the anesthetic management for elective thoracoscopic bullae resection (TBR) using high thoracic epidural (TE) anesthesia in awake patients. Pain and cough reflex caused by the surgical procedure could be controlled well with high TE anesthesia using 20-25 ml of 2% lidocaine. Respiratory and hemodynamic conditions remained stable during the surgical procedure. High TE anesthesia using a large dose of local anesthetic is thought to be suitable for TBR.

Characterization of prostanoid receptors mediating contraction of the gastric fundus and ileum: studies using mice deficient in prostanoid receptors.

Receptors mediating prostanoid-induced contractions of longitudinal sections of gastric fundus and ileum were characterized by using tissues obtained from mice deficient in each type and subtype of prostanoid receptors. The fundus and ileum from mice deficient in either EP(3) (EP(3)(-/-) mice), EP(1) (EP(1)(-/-) mice) and FP (FP(-/-) mice) all showed decreased contraction to PGE(2) compared to the tissues from wild-type mice, whereas contraction of the fundus slightly increased in EP(4)(-/-) mice. 17-phenyl-PGE(2) also showed decreased contraction of the fundus from EP(3)(-/-), EP(1)(-/-) and FP(-/-) mice. Sulprostone showed decreased contraction of the fundus from EP(3)(-/-) and FP(-/-) mice, and decreased contraction of the ileum to this compound was seen in tissues from EP(3)(-/-), EP(1)(-/-) and FP(-/-) mice. In DP(-/-) mice, sulprostone showed increased contraction. DI-004 and AE-248 caused the small but concentration-dependent contraction of both tissues, and these contractions were abolished in tissues obtained from EP(1)(-/-) and EP(3)(-/-) mice, respectively, but not affected in other mice. Contractions of both fundus and ileum to PGF(2)alpha was absent at lower concentrations (10(-9) to 10(-7) M), and suppressed at higher concentrations (10(-6) to 10(-5) M) of the agonist in the FP(-/-) mice. Suppression of the contractions at the higher PGF(2)alpha concentrations was also seen in the fundus from EP(3)(-/-), EP(1)(-/-) and TP(-/-) mice and in the ileum from EP(3)(-/-) and TP(-/-) mice. Contraction of the fundus to PGD(2) was significantly enhanced in DP(-/-) mice, and contractions of the fundus and ileum to this PG decreased in FP(-/-) and EP(3)(-/-) mice. Contractions of both tissues to I-BOP was absent at 10(-9) to 10(-7) M and much suppressed at higher concentrations in TP(-/-) mice. Slight suppression to this agonist was also observed in the tissues from EP(3)(-/-) mice. PGI(2) induced small relaxation of both tissues from wild-type mice. These relaxation reactions were much potentiated in EP(3)(-/-) mice. On the other hand, significant contraction to PGI(2) was observed in both tissues obtained from IP(-/-) mice. These results show that contractions of the fundus and ileum induced by each prostanoid agonist are mediated by actions of this agonist on multiple types of prostanoid receptors and in some cases modified by its action on relaxant receptors.

Electroacupuncture potentiates the antinociceptive effect of intrathecal endomorphin-1 in the rat formalin test.

Endomorphin-1 is a novel endogenous mu-opioid peptide. In this study, we examined the effects of 2 Hz electroacupuncture in the rat tail flick test and the formalin test (a persistent noxious model). Moreover, we investigated if the electroacupuncture potentiated the effect of intrathecal endomorphin-1. The results demonstrated that electroacupuncture alone produced a significant antinociception in the tail flick test, but not in the formalin test, and that intrathecal endomorphin-1 dose-dependently suppressed the biphasic nociceptive behavior in the formalin test. Electroacupuncture enhanced the antinociceptive effect of intrathecal endomorphin-1 in the formalin test, resulting in a significant leftward shift in the dose-response curves for intrathecal endomorphin-1 antinociception. The enhanced effect was antagonized by intraperitoneal naltrexone. The study suggests that electroacupuncture may potentiate the intrathecal endomorphin-1 antinociception partially mediated by opioid receptors.

[Sick sinus syndrome (SSS) after induction of anesthesia in a patient with increased intracranial pressure and ischemic heart disease].

An 84-year-old male with increased intracranial pressure (ICP) and ischemic heart disease was scheduled to undergo brain tumor resection. After induction of anesthesia using midazolam, fentanyl and vecuronium, sinus bradycardia, junctional rhythm and escape-capture bigeminy were observed. In spite of intravenous administration of lidocaine and atropine, the bigeminy did not disappear. As he awoke from anesthesia, his cardiac rhythm changed from a bigeminal to a regular sinus rhythm. After extubation, sinus arrest, which continued for up to 4.8 seconds, appeared frequently. A temporary pacing catheter was inserted and ventricular pacing was started (mode VVI rate 50 min-1). Four days later, the patient was again scheduled to undergo brain tumor resection. After induction of anesthesia with the same drugs as used before, his cardiac rhythm gradually became bradycardic, and a complete pacing rhythm was observed throughout the surgical procedure. After the operation had been completed, his cardiac rhythm changed to a regular sinus rhythm. In addition to degenerative and ischemic changes in the SA node, an increase in ICP secondary to a brain tumor is thought to have induced sick sinus syndrome after the induction of anesthesia.

[Anesthetic management of MIDCAB in a patient with Wolff-Parkinson-White syndrome].

We experienced the anesthetic management of a minimally invasive direct coronary artery bypass (MIDCAB) in a patient with Wolff-Parkinson-White (WPW) syndrome. A 55-year-old male had chest pain on effort and was diagnosed as having stenosis of the left coronary artery (#6). He was scheduled to undergo MIDCAB. Anesthesia was induced with midazolam 5 mg, fentanyl 300 micrograms, and vecuronium 10 mg and maintained with air-oxygen, propofol, and fentanyl (27 micrograms.kg-1). Diltiazem was continuously infused at a rate of 0.5-1.5 micrograms.kg-1.min-1 throughout the surgery. The hemodynamic parameters were maintained stable and paroxysmal supraventricular tachycardia was not observed during the procedure. We conclude that the administration of propofol and a medium dose of fentanyl is useful for the anesthetic management of MIDCAB in patients with WPW syndrome and that intraoperative administration of diltiazem might be needed to avoid paroxysmal supraventricular tachycardia.