Robotic assistance in the coordination of patient care

We conducted a study to investigate trust in and dependence upon robotic decision support among nurses and doctors on a labor and delivery floor. There is evidence that suggestions provided by embodied agents engender inappropriate degrees of trust and reliance among humans. This concern represents a critical barrier that must be addressed before fielding intelligent hospital service robots that take initiative to coordinate patient care. We conducted our experiment with nurses and physicians, and evaluated the subjects’ levels of trust in and dependence upon high- and low-quality recommendations issued by robotic versus computer-based decision support. The decision support, generated through action-driven learning from expert demonstration, produced high-quality recommendations that were accepted by nurses and physicians at a compliance rate of 90%. Rates of Type I and Type II errors were comparable between robotic and computer-based decision support. Furthermore, embodiment appeared to benefit performance, as indicated by a higher degree of appropriate dependence after the quality of recommendations changed over the course of the experiment. These results support the notion that a robotic assistant may be able to safely and effectively assist with patient care. Finally, we conducted a pilot demonstration in which a robot-assisted resource nurses on a labor and delivery floor at a tertiary care center.

Histochemical and Ultrastructural Analyses of the Epithelial Cells of the Body Surface Skin from the Terrestrial Slug, Incilaria fruhstorferi

Dorsal and ventral epithelium of the terrestrial slug, Incilaria fruhstorferi, is simple and consists of five cell types: microvillous, ciliated, round mucous, tubular mucous and channel. Microvillous cells were similar to human intestinal epithelial cells morphologically and functionally. At the base of microvilli, pinocytic vesicles which ultimately fused to form larger vacuoles, or multivesicular bodies were present. At the edge of tail or mouth, ciliated epithelial cells possessed the typical axonemes (9 plus 2 arrangement of microtubles). Mucous secretory cells were either tubular or round and their granules were membrane-bound and secreted by exocytosis. Granules of round mucous cells were proteinaceous but those of tubular cells were acidic mucopolysaccharides. Channel cells were elongate U-shaped and the central lumen was filled with a large amount of fluid (hemolymph). The function of channel cells is thought to remove hemolymph accumulated during hyperhydration. Our experiments of some markers-injection revealed that the fluid containing large molecules passed transcellularly from the hemolymph, across the basal or side region of the cell and into the central lumen. These results suggest that channel cell of the slug skin and vertebrate nephron showed some parallels in structure and function.

A comparison of morphine concentrations for patient-controlled epidural analgesia following gynecological surgery

AIM

To compare the analgesic efficacy of a lower (12.5 mg/mL) vs. higher (25 mg/mL) concentration of morphine with 0.2% ropivacaine for patient-controlled epidural analgesia (PCEA) following gynecological surgery.

METHODS

In a randomized double-blinded study, 40 ASA physical status I and II gynecological patients who were receiving combined general and epidural anesthesia for surgery and epidural analgesia for postoperative analgesia were assigned to receive 12.5 mg/mL (N=20) or 25 mg/mL (N=20) morphine with 0.2% ropivacaine for PCEA (continuous infusion 4 mL/h, bolus injection 2 ml, lockout interval 15 min). Maximum visual analogue pain scores (VAPS) at rest (VAPS-R max) and movement (VAPS-M max) during the previous 24 hours were assessed at 24 and 48 hours postoperatively, and the cumulative number of self-administrations in PCEA during the postoperative 48 h were also measured.

RESULTS

There were no significant differences in VAPS at rest or with movement, and there were no differences in the cumulative boluses of PCEA between the groups. The incidences of nausea, vomiting, pruritus and leg numbness were greater in the 25 mg/mL morphine group, although statistically insignificant.

CONCLUSIONS

PCEA using 0.2% ropivacaine and 12.5 mg/mL morphine compared with 0.2% ropivacaine and 25 mg/mL morphine provides equianalgesia with no differences in bolus administration. With respect to the analgesic efficacy and the potential risk for side effects, PCEA using 0.2% ropivacaine and 12.5 mg/ml morphine is a better choice for postoperative gynecological patients.

Airtraq optical laryngoscope: tracheal intubation by novice laryngoscopists

OBJECTIVE

To evaluate the performance of the Airtraq optical laryngoscope for tracheal intubation by novice laryngoscopists, compared with that of the Macintosh laryngoscope.

METHODS

Under supervision by staff anaesthetists, non-anaesthesia physicians performed tracheal intubation using either the Airtraq optical laryngoscope (n = 100) or the Macintosh laryngoscope (n = 100). The time required for airway instrumentation, the number of attempts until successful intubation and erroneous oesophageal intubation were investigated.

RESULTS

The time to secure the airway was shorter with the Airtraq optical laryngoscope than with the Macintosh laryngoscope (p<0.001). The number of attempts until successful intubation was smaller with the Airtraq optical laryngoscope than with the Macintosh laryngoscope (p<0.001). Erroneous oesophageal intubation was less with the Airtraq optical laryngoscope than with the Macintosh laryngoscope (p<0.01).

CONCLUSION

The Airtraq optical laryngoscope reduces the time to secure the airway and the incidence of failed tracheal intubation by novice laryngoscopists.

Cervical spine movement during laryngoscopy using the Airway Scope compared with the Macintosh laryngoscope

The Airway Scope is a new rigid laryngoscope. This intubation device provides a non-line-of sight view of the glottis. A non-line-of sight view is expected to cause less movement of the cervical spine during laryngeal visualisation. We compared the degree of cervical spine movement during laryngoscopy with the Airway Scope and conventional direct laryngoscope. Twenty patients requiring general anaesthesia and tracheal intubation were studied. Movements of the cervical spine were measured using radiography in the same patient during laryngoscopy with the Airway Scope and a Macintosh laryngoscope. Cervical spine movement during laryngoscopy with the Airway Scope was 37%, 37% and 68% less than that with the Macintosh laryngoscope at the C0/C1, C1/C2 and C3/C4 motion segments, respectively (p < 0.05). The movement of the atlanto-occipital distance using the Airway Scope was 42% less than that during laryngoscopy using the Macintosh laryngoscope (p < 0.05). Laryngoscopy using the Airway Scope involves less movement of the cervical spine compared to conventional laryngoscopy using the Macintosh laryngoscope.

Male New Zealand Black/KN mice: a novel model for autoimmune-induced permanent alopecia?

BACKGROUND

Irreversible, permanent and scarring alopecia is associated with several autoimmune diseases, including all autoimmune connective tissue disorders. The pathogenesis of autoimmune-induced permanent alopecia (APA) is still poorly understood, and instructive, simple mouse models for the study of APA are needed urgently. During the course of our studies in a well-established mouse model for chronic rheumatoid arthritis, the New Zealand Black/KN (NZB/KN) mouse, we noticed that ageing male NZB/KN mice developed spontaneous APA.

OBJECTIVES

To study whether alopecia seen in ageing male NZB/KN mice displays key features of human APA and may, thus, be a useful new mouse model for clinically relevant APA research.

METHODS

NZB/KN, the F1 hybrid of NZW/N Slc x NZB/KN (W/BKN F1), the F1 hybrid of NZB/KN x NZW/N Slc (BKN/W F1), and the F2 hybrid of W/BKN F1 x W/BKN F1 mice were employed in this study, in order to check which strain carries the highest risk of alopecia development. Besides routine histology, CD3, CD4 and CD8 expression as well as immunoglobulin (Ig) G and IgM deposition in hair follicles were investigated by immunohistology/immunofluorescence. Mast cell distribution/degranulation and Ki-67 (proliferation)/TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labelling) (apoptosis) positive cells were also analysed.

RESULTS

Only F2 male NZB/KN mice were prone to develop alopecia, suggesting that Y chromosome-associated gene(s) are involved in the pathogenesis of APA, which incidence rises with increasing age. The lesional alopecia skin in 12-month-old male NZB/KN mice showed a sharp decline in hair follicle density, thus meeting a key criterion of permanent alopecia. Both macroscopically and histologically, the alopecia seen in these mice resembled in many respects different stages of clinical APA, such as alopecia associated with chronic discoid lupus erythematosus (DLE) in humans. Lesional APA hair follicles in mice displayed intrafollicular and perifollicular mononuclear cell infiltrates, as well as an increased number of activated (degranulated) perifollicular mast cells. In the fully developed lesion, many CD4+ cells were seen in perifollicular locations, including the epithelial stem cell region (bulge), and also contained a few CD8+ T cells. IgM deposits were found in the follicular basement membrane zone (BMZ). Both in the bulge and the hair matrix region of the affected anagen hair follicles, there were signs of massive keratinocyte apoptosis.

CONCLUSIONS

Our currently available data suggest that male but not female NZB/KN mice may indeed represent a suitable mouse model for APA, with some similarities to the permanent alopecia seen in human DLE patients, although additional and confirmatory investigations are needed before this mouse strain can be accepted as a murine equivalent of APA in humans.

Genetic background differences between FVB and C57BL/6 mice affect hypnotic susceptibility to pentobarbital, ketamine and nitrous oxide, but not isoflurane

BACKGROUND

Pharmacogenomics has allowed us to identify the mechanisms underlying much of the inherited variability in drug response. There have been several reports of strain-dependent anesthetic actions in rodents, indicating that significant genetic differences exist in the hypnotic and antinociceptive effects of various anesthetics.

METHODS

Loss of righting reflex was used to compare the hypnotic action of pentobarbital, ketamine, nitrous oxide and isoflurane between two genetically different populations of mice, C57BL/6 with black hair and Friends virus B (FVB) with white hair.

RESULTS

C57BL/6 mice were more susceptible than FVB mice to the hypnotic effects of ketamine, pentobarbital and nitrous oxide. However, the sensitivity to isoflurane did not differ between C57BL/6 and FVB mice.

CONCLUSION

Genetic background affects the hypnotic susceptibility to some anesthetic agents in mice. Our results indicate that there may be a different genetic basis for the operation of hypnosis between isoflurane and other anesthetics, such as pentobarbital, ketamine and nitrous oxide.

Effect of continuous infusion of propofol on its concentration in blood with and without the liver in pigs

In living donor liver transplantation, propofol, an intravenous anesthetic drug, has recently been used in both donors and recipients. Propofol is known to have intra- and extrahepatic metabolic pathways, but the effect of its continuous infusion during a long-term anhepatic state is yet to be determined. Recently, we successfully established a simplified pig model of the complete anhepatic state. In this state, we first evaluated hemodynamic parameters relating to the pharmacokinetics of continuously infused propofol (6 mg.kg(-1) x h(-1)). No significant changes in the concentration of hemoglobin or in hemodynamic parameters other than the heart rate were observed during the anhepatic phase when porpofol was continuously infused at the rate that maintains the state. Blood propofol concentrations in the mixed vein, artery, and portal vein were stable during the anhepatic phase. Finally, we confirmed the pharmacokinetics of continuously infused propofol using orthotropic liver transplantation in miniature pigs. The propofol concentration did not change markedly during the transplant procedure. In conclusion, the pharmacokinetics of continuously infused propofol was almost stable with and without the liver in pigs. Extrahepatic metabolism of propofol might help prevent changes in propofol concentrations.

Evaluation of Intraoperative Infusion Solution Using a Complete Anhepatic Model in Baby Pigs

Compared to cadaveric liver transplantation, living-related liver transplantation (LRLT) has the physiological advantage of avoiding hemodynamic changes due to the nonsystemic clamping of the inferior vena cava (IVC). However, metabolic changes in the level of blood glucose and lactate usually occur during the anhepatic phase in LRLT. For pediatric patients, intraoperative infusions have the potential to maintain immature homeostasis during LRLT. In the present study, a complete anhepatic model of baby pigs with nonsystemic clamping of IVC, which mimics the procedure of pediatric LRLT, was established using a heparin-coated tube as an internal shunt lactate Ringer solution (LR, Lactec), acetate Ringer solution (AR, VeenF), and a solution comprising acetate Ringer with 1% glucose (AR-G, Phisio140) were tested using piglets. Hemodynamic and metabolic (blood gas analysis, electrolytes, blood lactate, and glucose) changes were observed during the anhepatic phase. Although no major difference was observed in hemodynamic parameters, arterial blood gas data, or concentration of electrolytes among the three solution groups, significant progressive hyperlactatemia was observed in the LR group. Also, though severe hypoglycemia was found in the LR and AR groups, the AR-G group maintained blood glucose levels throughout the anhepatic phase. To conclude, using the simplified pig anhepatic model, we evaluated various solutions for pediatric LRLT.

Lysis of adhesions and epidural injection of steroid/local anaesthetic during epiduroscopy potentially alleviate low back and leg pain in elderly patients with lumbar spinal stenosis †

BACKGROUND

Lumbar spinal stenosis causes various forms of back or leg pain, and is recognized with increasing frequency in elderly patients whose physical status is not always suitable for surgery. Epiduroscopy, a new, minimally invasive diagnostic and therapeutic technique, may be useful for pain relief in such patients. We investigated the epiduroscopic findings and immediate and long-term changes in back and leg pain after epiduroscopy in elderly patients with spinal stenosis.

METHODS

Patients with degenerative lumbar spinal stenosis (n=58, median age 71 yr) were divided into two groups based on presenting symptoms: a monosegmental group (n=34) and a multisegmental group (n=24). Each patient underwent epiduroscopy, and the findings were evaluated using visual analogue scales for low back and leg symptoms. Epiduroscopy included breaking down adhesions in the epidural space by injections of saline, and injection of steroids/local anaesthetic.

RESULTS

Epiduroscopy showed that the amount of fatty tissue and the degree of vascularity were greater in the monosegmental group than in the multisegmental group. Relief of low back pain was observed up to 12 months after epiduroscopy in both groups. Relief of leg pain was evident up to 12 months after epiduroscopy in the monosegmental group, and up to 3 months after epiduroscopy in the multisegmental group. None of the patients showed deterioration of motor or sensory deficits during follow-up. One patient was excluded from analysis because of accidental dural puncture during the procedure.

CONCLUSIONS

The findings of epiduroscopy corresponded to the symptoms. Epiduroscopy may reduce low back and leg pain in elderly patients with degenerative lumbar spinal stenosis, particularly those with radiculopathy.

Susceptibility of T cell receptor-alpha chain knock-out mice to ultraviolet B light and fluorouracil: a novel model for drug-induced cutaneous lupus erythematosus

The anticancer agent 5-fluorouracil (FU) frequently induces cutaneous lupus erythematosus (LE) lesions on sun exposed sites. Based on this observation, we have tried to establish a cutaneous LE model of C57BL/6 J (B6) mice, B6 T cell receptor (TCR)-alpha(-/-) mice and B6 TCR-delta(-/-) mice treated with FU and/or ultraviolet B light (UVBL) in order to clarify the role of T cells and the cytokine profile of cutaneous lupus lesions. Cutaneous LE-like skin lesions could be induced in TCR-alpha(-/-) mice with low FU (0.2 mg) plus UVBL, and in B6 mice treated with a high dose of FU (2.0 mg) plus UVBL. In contrast, low FU plus UVBL induced such skin lesions in TCR-delta(-/-) mice at a very low incidence. Specifically, the skin lesions of TCR-alpha(-/-) mice with low FU plus UVBL appeared more rapidly and were more severe than lesions in B6 mice. The former had the common characteristic features of human chronic cutaneous LE such as typical histology, positive IgG at the dermoepidermal junction, low antinuclear antibody and low mortality. Furthermore, a Th1 response was induced in the development of drug-induced cutaneous LE. FU and UVBL-induced cutaneous LE-like eruption is an excellent model for better understanding the pathomechanisms of skin lesion development in LE.

Chronopharmacological studies of ketamine in normal and NMDA epsilon1 receptor knockout mice

BACKGROUND

The effectiveness and toxicity of many drugs depends on the dosing-time schedule, relative to the circadian rhythms of biochemical, physiological, and behavioural processes. Previous studies have found chronopharmacology of ketamine, which is a N-methyl-d-aspartate (NMDA) receptor antagonist. The in vivo contribution of the NMDA receptor epsilon1 subunit (NR2A) in this effect is unclear.

METHODS

In the present study, daily variations in the hypnotic effect of ketamine were determined in wild-type mice and NMDA epsilon1 knockout (KO) mice.

RESULTS

The effect of ketamine had a definite daily variation in wild-type mice. No significant difference in blood concentration was observed at different dosing times (10:00 and 22:00). In NMDA receptor epsilon1 KO mice, the hypnotic effect of ketamine was weaker than in wild-type mice and there was no dependence on the time of administration. Significant pharmacokinetic differences were not observed between wild-type and KO mice.

CONCLUSIONS

The enhanced hypnotic effect in the active phase of the circadian cycle is likely a result of changes with the time of day in the susceptibility of the central nervous system to ketamine. Knockout of the NMDA receptor epsilon1 subunit gene markedly reduced the effect of ketamine, and eliminated the time-dependent sensitivity to ketamine.

Anesthesia-related mortality and morbidity over a 5-year period in 2,363,038 patients in Japan

BACKGROUND

Statistical data of mortality and morbidity related to anesthesia have not been reported in Japan since World War II. The need to comprehensively examine the events of cardiac arrest as well as mortality prompted the first national study in Japan.

METHODS

Confidential questionnaires were sent to all Japan Society of Anesthesiologists Certified Training Hospitals every year from 1994 through 1998. Collected data were analyzed for incidence of cardiac arrest and other critical events during anesthesia and surgery, and their outcomes within 7 postoperative days. The principal causes of the critical incidents were also analyzed.

RESULTS

With an average response rate of 39.9%, a total of 2,363,038 cases were documented over 5 years. The average incidence per year of cardiac arrest during surgery due to all etiologies and that totally attributable to anesthesia was 7.12 [95%CI: 6.30,7.94] and 1.00 [0.88, 1.12]) per 10,000 cases, respectively. The average mortality per year in the operating room or within 7 postoperative days due to all etiologies and that totally attributable to anesthesia was 7.18 [6.22, 8.13] and 0.21 [0.15, 0.27] per 10,000 cases, respectively. The two principal causes of cardiac arrest during anesthesia and surgery due to all etiologies were massive hemorrhage (31.9%) and surgery (30.2%), and those totally attributable to anesthesia were drug overdose or selection error (15.3%) and serious arrhythmia (13.9%). Preventable human errors caused 53.2% of cardiac arrest and 22.2% of deaths in the operating room totally attributable to anesthesia.

CONCLUSIONS

The rates in Japan of cardiac arrest and death during anesthesia and surgery due to all etiologies as well as those totally attributable to anesthesia are comparable to those of other developed countries.

Augmentation of monocyte interleukin-8 production by psoralen/UVA-treated CD4+ T cells

Treatment of cells with psoralen and ultraviolet A light (UVA) modulates their cytokine production. As extracorporeal photochemotherapy has been reported to induce cytokine production by monocytes, we quantified interleukin-8 (IL-8), a representative chemokine produced by monocytes, in culture supernatants from human peripheral blood mononuclear cells (PBMC) treated with 8-methoxypsoralen (8-MOP) and UVA. Lipopolysaccharide stimulated IL-8 production in 8-MOP-phototreated PBMC more efficiently than those untreated or treated with 8-MOP or UVA. More interestingly, when cultured with T-cell-stimulating anti-CD3 and anti-CD28 antibodies, 8-MOP/UVA-treated PBMC produced enhanced amounts of IL-8 with an increased level of IL-8 mRNA expression. Depletion of CD4 but not CD8 T cells from PBMC abrogated this augmented IL-8 elaboration, and CD4 T cells per se secreted no substantial amount of IL-8 even upon CD3/CD28 stimulation. Thus, 8-MOP/UVA-treated CD4 T cells stimulated monocytes to secrete IL-8. The IL-8 overproduction was induced by direct contact of monocytes with 8-MOP/UVA-treated CD4 T cells but not by cytokines from the treated CD4 T cells. These findings imply that in extracorporeal photochemotherapy, monocytes effectively produce IL-8 by cell-to-cell contact with 8-MOP/UVA-treated malignant CD4 T cells. The augmentation of monocyte cytokine/chemokine production by 8-MOP/UVA may be one of the mechanisms underlying the therapeutic efficacy of extracorporeal photochemotherapy.

An anaphylactic reaction to blood supplied from patient's mother

We present the case of a 4-year-old girl who developed anaphylactic shock during general anesthesia. Symptoms appeared 80 min into the operation and may have been an immediate allergic reaction to the transfused blood supplied from the child's mother based on the clinical signs, the decrease of components of complements and the elevated concentrations of histamine and tryptase. The blood type was the same and antibody screening test and crossmatch was negative. The blood was irradiated and we used a white cell-reduction filter. This patient possibly has antibodies to her mother's plasma and this type of reaction cannot be prevented by these routine methods. It is reported that the risk of transfusion associated graft-vs.-host disease is high when a patient receives blood from a closely related donor. However, there are, no reports of anaphylactic reactions to blood supplied from mother to child. We suggest that there is a potential for anaphylactic reaction as well as transfusion associated graft-vs.-host disease when a child patient receives blood from the mother.

Spontaneous breathing combined with high frequency ventilation during bronchoscopic resection of a large tracheal tumour

A patient with learning difficulties had a large tracheal tumour at the carina that caused severe respiratory distress. I.v. anaesthesia with propofol, spontaneous breathing through a tracheal tube, and high frequency jet ventilation were successfully employed during bronchoscopic resection of the tumour.

[Annual study of perioperative mortality and morbidity for the year of 1999 in Japan: the outlines--report of the Japan Society of Anesthesiologists Committee on Operating Room Safety]

Anesthetic mortality and morbidity in Japan Society of Anesthesiologists (JSA) Certified Training Hospitals (CTH) for the year 1999 were reported as continuation of annual studies started in 1993. The JSA Committee on Operating Room Safety (CORS) sent confidential questionnaires to 774 CTH and received valid responses from 60.3% of hospitals. A total number of 793,840 anesthetics were documented. The respondents were asked to report all cases of cardiac arrests and other critical incidents (serious hypotension, serious hypoxemia and others), and their outcomes (death in operating room, death within 7 days, transfer to vegetative state and rescue without sequelae) as well as one principal cause for each incident from list of 52 items. They were also requested to submit the tabulation of patients by ASA physical status, age distribution, surgery sites and anesthetic methods. Analysis was made by total incidents under anesthesia/surgery, and also by incidents totally attributable to anesthetic management (AM), due to preoperative complications (PC), due to intraoperative pathological events (IP) and due to surgery (SG), with special reference to each of four tabulation groups and the whole group of patients. This paper focused analysis on all patients, as analyses with special reference to ASA physical status, age distribution, surgery sites and anesthetic methods were previously reported. Total incidence of cardiac arrest under anesthesia/surgery was 6.53 per 10,000 anesthetics. PC, IP and SG represented principal causes in 42.9%, 22.0% and 21.4% causes of total cardiac arrest cases, respectively. AM was noted as the principal cause in 12.0% of cases, with an incidence rate of 0.78 per 10,000. In 52 more detailed classification of principal causes, the most frequent cause of cardiac arrest was preoperative hemorrhagic shock, 20.3% of all cardiac arrests. The second cause was massive hemorrhage and/or hypovolemia due to surgical procedures (13.1%), and the third was intraoperative myocardial infarction/coronary ischemia/coronary spasm (9.5%). Prognoses of cardiac arrest cases declined due to PC: 71.1% of cardiac arrests died in the operating room or within 7 days after surgery and only 19.8% survived without sequelae. The best prognoses were found in cardiac arrest cases due to AM: 69.4% survived without sequelae and 12.9% died. The mortality rate post-cardiac arrest was 3.44 per 10,000 anesthetics, of those 0.10 due to AM, 0.57 due to IP, 1.99 due to PC and 0.76 due to SG. The mortality rate after critical incidents other than cardiac arrest such as severe hypotension and severe hypoxemia was 3.75, of those 0.03 due to AM, 0.28 due to IP, 2.31 due to PC and 1.13 due to SG. The final mortality rate attributable to anesthesia/surgery including deaths post-cardiac arrest and after other critical incidents was 7.19 per 10,000 anesthetics and very close to 7.18 [6.22, 8.13], that of mean [95% C.I.] in 1994-1998. The final mortality rate totally attributable to anesthesia was 0.13 per 10,000 anesthetics, which was significantly improved from 0.21 [0.15, 0.27], that of mean [95% C.I.] in 1994-1998. IP, PC and SG showed the final mortality rate of 0.84, 4.30 and 1.89, respectively. Five major causes of all critical incidents were massive hemorrhage due to surgical procedures (20.8%), preoperative hemorrhagic shock (10.7%), surgical technique (8.0%), inappropriate airway management (5.2%) and intraoperative myocardial infarction and coronary ischemia (4.5%). Drug overdose or selection error (3.9%) and overdose of main anesthetic (2.9%) as a result of human error occupied the 7th and 10th places. As far as anesthetic management to reduce mortality and morbidity related to anesthesia is concerned, we should increase vigilance to avoid human errors in addition to improving preanesthetic preparations and assessment of cardiovascular status as well as intraoperative management of cardiovascular events.

Quinolone-photoconjugated major histocompatibility complex class II-binding peptides with lysine are antigenic for T cells mediating murine quinolone photoallergy

Fluoroquinolone antibacterial agents cause photosensitivity dermatitis as an adverse effect and can function immunologically as photohapten. In a murine model of quinolone photoallergy, Langerhans cells are photomodified with a systemically given quinolone upon ultraviolet A irradiation of skin and thus present photohaptenic moieties to sensitize and restimulate T cells. The aim of this study is to determine the site of peptides/proteins photobound to quinolones and to assess the T cell antigenicity of quinolone-photocoupled peptides using Langerhans cells as photoadduct-presenting cells. On an amino acid composition analysis, lysine was preferentially degraded in bovine serum albumin that was ultraviolet A-conjugated with a representative quinolone ofloxacin. An affinity chromatographic study using a quinolone photoadduct-specific monoclonal antibody as ligand demonstrated preferential photocoupling of ofloxacin with a lysine-containing peptide. CD4+ T cells were purified from lymph nodes of BALB/c mice sensitized subcutaneously with ofloxacin-photomodified epidermal cells and from those sensitized epicutaneously via barrier-disrupted skin with a major histocompatibility complex class II (I-Ad)-binding, ofloxacin-photoconjugated peptide. These immune T cells proliferated in vitro in response to Langerhans cells loaded with class II-binding, lysine-containing peptides when photomodified with ofloxacin. Furthermore, epicutaneous application of the ofloxacin-photoconjugated peptide was able to prime mice for subsequent elicitation of photoallergy evoked with systemic ofloxacin and ultraviolet A light. This study suggests that lysine affords quinolone photocoupling of peptides and quinolone-photomodified peptides on class II molecules stimulate pathogenetic T cells in quinolone photoallergy.

[The effect of obesity on spinal anesthesia for cesarean section]

To evaluate the effect of obesity on spinal anesthesia for cesarean section, we retrospectively studied 90 parturients who had undergone cesarean section, dividing the patients into 2 groups: obesity group (body mass index > 30, n = 41); control group (body mass index < 30, n = 49). Total surgical time and anesthetic time were longer in the obesity group than in the control group. The amount of ephedrine administered was also greater in the obesity group than in the control group. However, there were no significant differences in time for spinal tap and the incidence of hypotension between the two groups. Spinal anesthesia for cesarean section in obese patients may be an acceptable method.

[Epiduroscopy in patients with chronic low back pain without remarkable findings on magnetic resonance imaging]

Two patients with chronic low back pain and sciatica failed to respond to conservative treatments. In these patients, magnetic resonance imaging (MRI) showed no remarkable findings corresponding to their symptoms. We treated these patients using epiduroscopy. Epiduroscopic visualization of the spinal canal permits efficient adhesiolysis and irrigation. One patient got better after two epiduroscopic procedures, and the other did not. Epiduroscopy may be an effective, minimally invasive treatment as well as examination for patients with chronic low back pain without remarkable findings on MRI.

Regulation of acute nociceptive responses by the NMDA receptor GluRepsilon2 subunit

Heterozygous mice mutant for the NMDA-type glutamate receptor (GluR) epsilon2 subunit with a highly homogeneous genetic background showed exaggerated responses to various acute noxious stimuli in the footshock, tail-flick, hot-plate and tail-pinch tests. Because the noxious stimuli in these behavioral tests were electrical, thermal and mechanical, the reduction of GluRepsilon2 proteins exerted stimulatory effects on acute nociceptive responses across modalities. Previous studies showed that GluRepsilon1 and GluRepsilon4 subunit mutant mice exhibited no alteration in the responses to acute noxious stimuli. Thus, among NMDA receptor subunits, the GluRepsilon2 subunit specifically plays an important role in the regulation of the acute nociceptive responses.

[Questionnaires on patient-controlled analgesia to the nursing staff in the surgical ward]

Thirty-one nurses in the surgical ward engaged in delivering postoperative analgesia using patient-controlled analgesia (PCA) were asked to complete questionnaires on postoperative analgesia and PCA. Ninety-seven per cent of respondents agreed that the postoperative analgesia is beneficial for postoperative recovery, and answered that the desirable goal in postoperative analgesia is "no pain at rest". Not only "pain at movement" or "pain on coughing", but also "decreased conscious level while analgesia is achieved" were selected as undesirable conditions during postoperative course. Although no one had learned the concept of PCA in their nursing schools, 94 per cent of respondents approved PCA as a method for postoperative analgesia. Seventy seven per cent responded that PCA is effective in the pain relief during position change, pulmonary physiotherapy and induced early ambulation. In addition, 65 per cent of respondents chose PCA as a method for postoperative analgesia when they receive thoraco-abdominal surgery. On the other hand, some problems on pain management using PCA, such as taking care of patients' ambulation with carrying a PCA pump, extra time for instruction of PCA and extra support for patients' psychological state were listed. In conclusion, these results suggest that PCA is accepted as an excellent method for postoperative analgesia among our nurses in the surgical ward, and education in postoperative pain management including PCA is required in nursing school as well as after graduation.

Hypersensitivity to mosquito bites as the primary clinical manifestation of a juvenile type of Epstein-Barr virus-associated natural killer cell leukemia/lymphoma

Hypersensitivity to mosquito bites or mosquito allergy is a mysterious disorder that has been reported mainly in Japanese patients (at least 58 patients) in the first two decades of life. The skin lesion at bite sites is typically a bulla that develops into necrosis. Patients simultaneously exhibit a high temperature and general malaise and subsequently may experience lymphadenopathy and hepatosplenomegaly. Recent studies have revealed that this mosquito hypersensitivity is associated with chronic Epstein-Barr virus infection and natural killer cell leukemia/lymphoma. The natural killer cell, infected with monoclonal (or oligoclonal) Epstein-Barr virus, seems to be involved in the pathogenesis of the hypersensitivity. Half of the patients reported died of hemophagocytic syndrome (or malignant histiocytosis), granular lymphocyte proliferative disorder, or lymphomas. We propose that this disease, defined as the triad of hypersensitivity to mosquito bites, chronic Epstein-Barr virus infection, and natural killer cell leukemia/lymphoma, is a clinical entity mostly seen in Asians.

[Perioperative mortality and morbidity for the year 1999 in 466 Japanese certified anesthesia-training hospitals: with special reference to operative regions--report of Committee on Operating Room Safety of Japanese Society of Anesthesiologists]

Perioperative mortality and morbidity in Japan for the year 1999 were analyzed retrospectively with special reference to operative regions. The total number of analyzed cases was 701,940. The percentages for each operative region were as follows, craniotomy 4.5%, thoracotomy 3.3%, heart and great-vessels 3.9%, thoracotomy with laparotomy 0.8%, laparotomy except caeserian-section 31.7%, ceserian-section 3.2%, head-neck and otolarynx 14.5%, chest-abdomen-perineum 11.1%, spine 3.5%, extremity including peripheral-vessel 16.5%, and others 6.9%. The incidence of serious events, including cardiac arrest and severe hypotension and hypoxemia suggesting impending cardiac arrest was 34.58 per 10,000 cases in all operative regions. The events were observed more frequently in heart and great-vessels 247.26, thoracotomy with laparotomy 128.91 and thoracotomy 61.55, and less frequently in chest-abdomen-perineum 13.52 and extremity including peripheral-vessel 16.99. Regarding the prognosis of events, the cases with no sequela were 69.9% in all operative regions. While there were fewer cases with no sequela in craniotomy 50.4%, thoracotomy with laparotomy 54.3% and heart and great-vessels 58.6%, there were more cases in head-neck and oto-larynx 95.2% and chest-abdomen-perineum 90.5%. The incidence of serious events totally attributable to anesthetic management was 7.79 per 10,000 cases in all operative regions. The events were observed more frequently in thoracotomy 12.82, heart and great-vessels 12.29 and spine 11.06, and less frequently in extremity including peripheral-vessel 5.17 and chest-abdomen-perineum 6.05. Regarding the prognosis of events, the cases with no sequela were 93.1% in all operative regions. There were fewer cases with no sequela in thoracotomy with laparotomy 80.0% and craniotomy 81.8%. The main cause of events in thoracotomy and spine was the inadequate airway management, and in heart and great-vessels was the overdose or miss-selection of drugs. Although the incidence of serious events totally attributable to anesthetic management was one fourth of all events, most of them resulted from human factors. Thus, the more efforts are necessary to improve the outcomes. While the total deaths from 701,940 cases, including death on the operation day or within 7 days after it, were 528 cases (7.52 per 10,000 cases), the deaths totally attributable to anesthesia were 7 cases (0.10 per 10,000 cases).

[Annual report of perioperative mortality and morbidity for the year 1999 with a special reference to anesthetic methods at Certificated Training Hospitals of Japanese Society of Anesthesiologists]

The Committee on Operating Room Safety of Japanese Society of Anesthesiologists (JSA) sends annually confidential questionnaires of perioperative mortality and morbidity to Certificated Training Hospitals of JSA. This report is on perioperative mortality and morbidity in 1999 with a special reference to anesthetic methods. Four hundred and sixty-seven hospitals reported the number of cases referred to anesthetic methods and total numbers of cases were 727,723. The incidences of cardiac arrest per 10,000 cases due to all etiology are estimated to be 6.77 cases in average, 5.33 cases in inhalation anesthesia, 34.26 cases in total intravenous anesthesia (TIVA), 5.26 cases in inhalation anesthesia plus epidural or spinal or conduction block, 5.29 cases in TIVA plus epidural or spinal or conduction block, 0.73 cases in spinal with continuous epidural block (CSEA), 2.85 cases in epidural anesthesia, 1.63 cases in spinal anesthesia, 2.53 cases in conduction block and 46.51 cases in other methods. However, the incidences of cardiac arrest per 10,000 cases totally attributable to anesthesia are estimated to be 0.78 case in average, 0.51 case in inhalation anesthesia, 1.35 cases in TIVA, 0.97 case in inhalation anesthesia plus epidural or spinal or conduction block, 1.51 cases in TIVA plus epidural or spinal or conduction block, 0.73 case in CSEA, 1.71 cases in epidural anesthesia, 0.54 case in spinal anesthesia, 2.52 cases in conduction block and 1.08 cases in other methods. The incidences of severe hypotension per 10,000 cases due to all etiology are estimated to be 16.64 cases in average, 13.61 cases in inhalation anesthesia, 100.36 cases in TIVA, 13.32 cases in inhalation anesthesia plus epidural or spinal or conduction block, 9.07 cases in TIVA plus epidural or spinal or conduction block, 3.65 cases in CSEA, 6.26 cases in epidural anesthesia, 7.31 cases in spinal anesthesia, 2.52 cases in conduction block and 28.12 cases in other methods. On the other hand, the incidences of cardiac arrest per 10,000 cases totally attributable to anesthesia are estimated to be 2.40 cases in average, 1.65 cases in inhalation anesthesia, 0.81 cases in TIVA, 3.92 cases in inhalation anesthesia plus epidural or spinal or conduction block, 2.77 cases in TIVA plus epidural or spinal or conduction block, 2.56 cases in CSEA, 3.42 cases in epidural anesthesia, 2.71 cases in spinal anesthesia, zero case in conduction block and zero case in other methods. The incidences of severe hypoxia per 10,000 cases due to all etiology are estimated to be 5.32 cases in average, 6.7 cases in inhalation anesthesia, 9.17 cases in TIVA, 5.16 cases in inhalation anesthesia plus epidural or spinal or conduction block, 4.53 cases in TIVA plus epidural or spinal or conduction block, 2.56 cases in CSEA, zero case in epidural anesthesia, 1.08 cases in spinal anesthesia, zero case in conduction block and 1.08 cases in other methods. On the other hand, the incidences of severe hypoxia per 10,000 cases totally attributable to anesthesia are estimated to be 2.39 cases in average, 3.22 cases in inhalation anesthesia, 2.43 cases in TIVA, 2.26 cases in inhalation anesthesia plus epidural or spinal or conduction block, 2.77 cases in TIVA plus epidural or spinal or conduction block, zero case in CSEA, zero case in epidural anesthesia, 0.54 cases in spinal anesthesia, zero case in conduction block and 1.08 cases in other methods. The mortality rates of cardiac arrest per 10,000 cases due to all etiology are estimated to be 3.56 cases in average, 2.82 cases in inhalation anesthesia, 24.55 cases in TIVA, 1.4 cases in inhalation anesthesia plus epidural or spinal or conduction block, 1.51 cases in TIVA plus epidural or spinal or conduction block, zero cases in CSEA, 0.57 cases in epidural anesthesia, 0.27 cases in spinal anesthesia, zero case in conduction block and 42.18 cases in other methods. On the other hand, the mortality rates of cardiac arrest per 10,000 cases totally attributable to anesthesia are estimated to be 0.08 case in average, 0.09 case in inhalation anesthesia, 0.27 case in TIVA, 0.05 case in inhalation anesthesia plus epidural or spinal or conduction block, zero case in TIVA plus epidural or spinal or conduction block, zero case in CSEA, 0.57 case in epidural anesthesia, zero case in spinal anesthesia, conduction block and other methods. The outcomes of cardiac arrest totally attributable to anesthesia are 70.2% of full recovery without any sequelae, 10.5% of death within 7 days, 1.8% of vegetative state and 17.5% of unknown results while the outcome of critical events including severe hypotension and severe hypoxia totally attributable to anesthesia is 94.9% of full recovery without any sequelae, 0.4% of death within 7 days, 0.2% of vegetative state and 4.5% of unknown results. These results indicate that there are no differences in mortality and morbidity totally attributable to anesthesia among anesthetic methods in 1999 at Certificated Training Hospitals of Japan Society of Anesthesiologists.

Percutaneous peptide immunization via corneum barrier-disrupted murine skin for experimental tumor immunoprophylaxis

Percutaneous peptide immunization is a method in which tumor-specific cytotoxic T lymphocytes (CTL) are primed in the lymph nodes and spleen following application of tumor peptides to corneum barrier-disrupted murine skin. Immunized mice are protected against subsequent challenge with corresponding tumors and suppress the growth of established tumors. CTL expansion after peptide application seems to be mediated by epidermal Langerhans' cells. In the human, disruption of permeability barrier by tape stripping also induces activation of epidermal Langerhans' cells. Thus, percutaneous peptide immunization provides a simple and noninvasive means of inducing potent antitumor immunity that may be exploited for cancer immunotherapy in the human.

Photoactivational cytokine-modulatory action of 8-methoxypsoralen plus ultraviolet A in lymphocytes, monocytes, and cutaneous T cell lymphoma cells

Treatment with 8-methoxypsoralen (8-MOP) and ultraviolet A light (UVA) has been reported to modulate cytokine production in various cells. Our study was conducted to see the effects of 8-MOP/UVA on the expression/production of cytokines in peripheral blood lymphocytes and monocytes in relation to the therapeutic mechanisms of extracorporeal photochemotherapy. 8-MOP/UVA augmented the expression of mRNAs for interferon-gamma (IFN-gamma) and interleukin (IL)-2 and reduced those for IL-4 and IL-10 in peripheral blood mononuclear cells (PBMCs) from normal subjects and Sézary syndrome patients. This enhancement of Th1 cytokines was caused by increment of cytokine production by Th1 cells but not by conversion of Th2 cells to produce Th1 cytokines. The number of IFN-gamma-secreting lymphocytes was markedly increased in 8-MOP/UVA-treated PBMCs 20 h after treatment, and its amount was elevated in culture supernatants. However, this enhanced production of IFN-gamma was found only until three days after 8-MOP phototreatment, and its level was rapidly declined by five days after treatment. In addition to this Th1-polarized action, 8-MOP/UVA-treated PBMCs produced enhanced amounts of IL-8 upon stimulation with anti-CD3/CD28 antibodies. Phototreated CD4+ but not CD8+ cells provided excellent T cell help for monocytes to produce IL-8 via a direct cell-to-cell contact mechanism. These findings suggest that 8-MOP/UVA has a transient but biologically active Th1-skewing action in T cells, and the phototreated T cells simultaneously stimulate monocytes to produce IL-8. It is suggested that 8-MOP/UVA exerts a beneficial therapeutic effect on malignant Th2 neoplasms as a Th1-skewing cytokine modifier and that 8-MOP-phototreated CD4+ T cells allow monocytes to become effective tumor antigen-presenting cells for tumor-specific cytotoxic T cells.

[Anesthetic management of a morbidly obese patient undergoing laparoscopic gastric bypass surgery]

We describe a successful anesthetic management of a morbidly obese patient, weighing 170 kg, height of 170 cm and body mass index of 58.8 kg.m-2, who received gastric bypass surgery performed using laparoscopic assist. After arriving in the operating room, an epidural catheter was inserted into the epidural space at the T 7-8 intervertebral space. The trachea was intubated nasally under bronchofiberscopic assist, after which anesthesia was induced with propofol and maintained with nitrous oxide and oxygen (FIO2 = 0.5), i.v. propofol, fentanyl, and epidural anesthesia. Propofol infusion rate was determined using the corrected body weight drawn by Servin et al. Anesthetic management and recovering from anesthesia were uneventful. For propofol anesthesia, infusion rates determined using the corrected body weigh, was preferable for morbidly obese patients.

Interleukin-10 expressed at early tumour sites induces subsequent generation of CD4(+) T-regulatory cells and systemic collapse of antitumour immunity

We investigated the relationship between transforming growth factor-beta (TGF-beta)-secreting T-regulatory (Tr) cells and anti-B16 melanoma immunity, and studied the association of early cytokines expressed at tumour sites with the generation of Tr cells. A large number of CD4(+) Tr cells producing interleukin (IL)-4, IL-10 and TGF-beta accumulated with functionally depressed CD8(+) cytotoxic T lymphocytes (CTLs) at tumour sites on day 20 after subcutaneous (s.c.) inoculation of B16 tumour cells. Tr cells consisted of two populations, which were termed T helper 3 (Th3) and Tr1 cells. B16-infiltrating Tr cells strongly inhibited the generation of B16-specific T helper 1 (Th1) cells in a TGF-beta-dependent manner and were assumed to suppress effective generation of CTLs. In addition, B16 cells markedly progressed in mice transferred adoptively by the cultured B16-infiltrating Tr cells compared with untreated mice. The capacity of these Tr cells to produce TGF-beta was hampered by neutralizing anti-IL-10 and partly anti-IL-4 monoclonal antibodies (mAbs) injected intralesionally during the early development of B16 tumours, and this treatment markedly attenuated B16 growth. Furthermore, a lesional injection of recombinant mouse IL-10 at an early tumour site resulted in the vigorous progression of B16 tumours. These results provide evidence that Tr cells, belonging to the T helper 3/T-regulatory 1 (Th3/Tr1) type, are activated in B16-bearing hosts under the influence of T helper 2 (Th2) cytokines, mainly IL-10 (produced at early tumour lesions), and that this regulatory T-cell population functions as a suppressor of anti-B16 immunity.

[Perioperative mortality and morbidity in 1999 with a special reference to age in 466 certified training hospitals of Japanese Society of Anesthesiologists--report of Committee on Operating Room Safety of Japanese Society of Anesthesiologists]

Perioperative mortality and morbidity in Japan from Jan. 1 to Dec. 31, were studied retrospectively. Committee on Operating Room Safety of Japanese Society of Anesthesiologists (JSA) sent confidential questionnaires to 774 Certified Training Hospitals of JSA and received answers from 60.2% of the hospitals. We analyzed their answers with a special reference to the age group. The total number of anesthetics available for this analysis was 732,788. All cases were divided in to 7 groups; group A(< 1 months), group B(< 12 months), group C(< 5 years), group D(< 18 years), group E (< 65 years), group F(< 85 years), and group G(> 85 years). The incidences of all critical events including cardiac arrest, severe hypotension, and severe hypoxemia were 168.14, 47.86, 24.63, 14.65, 28.43, 50.4, and 43.68 per 10,000 in patients with group A, B, C, D, E, F, and G, respectively. The overall mortality rate (death during anesthesia and within 7th postoperative day) were 74.10, 6.63, 3.30, 3.07, 4.82, 13.74, and 11.84 per 10,000 anesthetics in patients with group A, B, C, D, E, F, and G, respectively. The incidences of cardiac arrest were 54.15, 8.84, 5.08, 2.56, 4.84, 11.02, and 6.66 per 10,000 in patients with group A, B, C, D, E, F, and G, respectively. The mortality rates after cardiac arrest were 42.75, 2.95, 2.54, 1.70, 2.00, 6.56, and 5.18 in patients with group A, B, C, D, E, F, and G, respectively. The incidences of all critical events, the incidence of cardiac arrest, and the overall mortality rate were much higher in group A than other groups and lower in group D. Mortality and morbidity due to all kinds of causes including anesthetic management, intraoperative events, co-existing diseases, and operation were as follows. The incidence of all critical events attributable to co-existing disease were the highest in these four groups, and 94.04, 15.46, 7.87, 6.13, 7.26, 17.38, and 16.29 per 10,000 in patients with group A, B, C, D, E, F, and G, respectively. The incidences of all critical events attributable to anesthetic management were 31.35, 16.94, 4.60, 6.09, 10.77, and 14.07 per 10,000 in patients with group A, B, C, D, E, F, and G, respectively. The incidence of cardiac arrest in group A was much more attributable to co-existing disease and operation than other causes. The incidences of cardiac arrest attributable to anesthetic management were 0.00, 1.47, 0.25, 0.34, 0.83, 0.92, and 0.22 per 10,000 in patients with group A, B, C, D, E, F, and G, respectively. The mortality rates in these groups were 0.00, 0.00, 0.00, 0.17, 0.07, 0.05, and 1.48, and no death was found in cases under 5 years of age. The two cases of death in G group were due to too high anesthesia levels in spinal anesthesia. Other causes including overdose of anesthetics, toxic effect of local anesthetic, improper management of airway, and incompatible blood transfusion were preventable with the anesthesiologists' effort in protocol development and skilled assistance.

[The effect of intravenous patient controlled analgesia on activities of daily life and medical expense after thoracotomy]

We investigated the efficacy of postoperative intravenous patient controlled analgesia (i.v.-PCA) combined with continuous epidural analgesia (CEA) after thoracotomy. One hundred and eight patients receiving postoperative CEA were randomly divided into two groups; the i.v.-PCA (+) group who received i.v.-PCA combined with CEA and the i.v.-PCA (-) group who did not receive i.v.-PCA. Pain score (100 mm visual analogue scale; VAS) at 24 h and 48 h, postoperative complications, activities of daily life (ADL), the length of hospital stay and medical expense were compared. The length of hospital stay and medical expense were not significantly different between the two groups. The i.v.-PCA (+) group could recover ADL more quickly and had better analgesic state compared with the i.v.-PCA (-) group. The incidence of postoperative complications was lower in the i.v.-PCA (+) group compared with the i.v.-PCA (-) group. It was concluded that the i.v.-PCA combined with CEA had the desirable effects on postoperative analgesia and recovery of postoperative ADL.

[Perioperative mortality and morbidity for the year of 1999 in 466 Japanese Certified Anesthesia-training Hospitals: with special reference to ASA-physical status--report of Committee on Operating Room Safety of Japan Society of Anesthesiologists]

Perioperative mortality and morbidity in Japan for the year 1999 were studied retrospectively. Committee on Operating Room Safety of the Japan Society of Anesthesiologists (JSA) sent confidential questionnaires to 774 Certified Training Hospitals of JSA and received answers from 60.2% of the hospitals. We analyzed their answers with special reference to ASA physical status (ASA-PS). The total number of anesthetics analyzed was 655, 644. Mortality and morbidity due to all kinds of causes including anesthetic management, intraoperative events, co-existing diseases, and operation were as follows. The incidence of cardiac arrest (per 10,000 anesthetics) was 0.68, 3.76, 14.37, 67.03, 0.36, 4.68, 27.96, 206.30 in patients with ASA-PS of I, II, III, IV, I E, II E, III E, and IV E, respectively. The incidences of critical events including cardiac arrest, severe hypotension, and severe hypoxemia were 8.93, 26.99, 71.30, 188.52, 8.68, 31.27, 136.16, and 790.92 in patients with ASA-PS of I, II, III, IV, I E, II E, III E, and IV E, respectively. The mortality rates (death during anesthesia and within 7th postoperative day) after cardiac arrest were 0.16, 0.94, 5.71, 33.51, 0.00, 1.46, 16.41 and 167.76 per 10,000 anesthetics in patients with ASA-PS of I, II, III, IV, I E, II E, III E, and IV E, respectively. The overall mortality rates were 0.24, 1.66, 12.16, 67.03, 0.00, 3.51, 34.65 and 417.14 in patients with ASA-PS of I, II, III, IV, I E, II E, III E, and IV E, respectively. Overall mortality and morbidity were higher in emergency anesthetics than in elective anesthetics. ASA-PS correlated well with overall mortality and with morbidity, regardless of etiology. The incidences of cardiac arrest totally attributable to anesthesia were 0.24, 0.45, 1.47, 8.38, 0.36, 1.75, 2.43 and 11.34 in patients with ASA-PS of I, II, III, IV, I E, II E, III E, and IV E, respectively. The incidences of all critical events totally attributable to anesthesia were 4.92, 8.81, 14.74, 20.95, 4.34, 11.40, 15.80 and 22.67 in patients with ASA-PS of I, II, III, IV, I E, II E, III E, and IV E, respectively. The mortality rates after cardiac arrest totally attributable to anesthesia were 0.00, 0.00, 0.61 and 4.53 in patients with ASA-PS of I-IV, I E-II E, III E, and IV E, respectively. The overall mortality rates totally attributable to anesthesia were 0.00, 0.04, 0.18, 0.00, 0.00, 0.61 and 4.53 in patients classified to ASA-PS of I, II, III, IV, I E-II E, III E, and IV E, respectively. Only one death, due to overdose of anesthetics, was reported among patients with good physical status (ASA-PS of I, II, II E and II E). Anesthetic management was mainly responsible for critical events in patients with good physical status, while co-existing diseases were in those with poor physical status. The major co-existing diseases or conditions leading to critical events were heart diseases in elective anesthetics, and hemorrhagic shock in emergency anesthetics. We reconfirmed that ASA-PS is beneficial to predict perioperative mortality and morbidity. It also seems likely that we should make much more efforts to reduce anesthetic morbidity in patients with good physical status, and to improve preanesthetic assessment and preparation of cardiovascular conditions in those with poor physical status.

[Perioperative management of three patients with streptococcal toxic shock syndrome]

We report the perioperative management of three patients with streptococcal toxic shock syndrome (STSS) caused by group A streptococcal infection. Three of two patients survived but one patient died from multiple organ dysfunction in spite of vigorous treatments. These patients required the treatments including administration of antibiotics, circulatory and respiratory care, surgical debridement, anticoagulant therapy for disseminated intravascular coagulation and hemofiltration. The early diagnosis and surgical intervention play a key role in the successful management of this syndrome because it has a rapid course and frequent fatal outcome. The anesthetic management of these patients should be targeted to maintain perfusion of the vital organs and to control the blood clotting disorders.

Nonerythrodermic, leukemic variant of cutaneous T-cell lymphoma with indolent clinical course: Th2-type tumor cells lacking T-cell receptor/CD3 expression and coinfiltrating tumoricidal CD8 T cells

As typically represented by Sézary syndrome, the leukemic form of cutaneous T-cell lymphoma (CTCL) mostly exhibits erythroderma. A patient with CTCL had slowly developing skin tumors as well as chronic leukemia. The tumor cell was CD4+ CD7- Th2 cells lacking T-cell receptor/CD3 complex and persistently occupied 27% to 48% of peripheral blood lymphocytes. In skin tumors, only 13% of tumor-infiltrating lymphocytes were malignant cells and substantial numbers of nonmalignant CD4+ or CD8+ T cells and B cells coinfiltrated. CD8+-infiltrating T cells had cytotoxic activity against the malignant T cell. Our case demonstrates the existence of the leukemic form of CTCL presenting with skin manifestation other than erythroderma and parapsoriatic patches. The nonerythrodermic feature and indolent course may be associated with the lack of T-cell receptor/CD3 expression and coinfiltration of a high percentage of nontumor lymphocytes, including tumoricidal CD8+ T cells.

[Intravenous patient controlled analgesia combined with continuous thoracic epidural analgesia for post-thoracotomy pain]

We compared the efficacy of intravenous patient controlled analgesia of buprenorphine plus continuous thoracic epidural infusion of bupivacaine (IV-PCA group) with the efficacy of continuous thoracic epidural infusion of bupivacaine and buprenorphine (the TEA group). No patient in IV-PCA group required supplemental analgesics, while 90% of TEA group required supplemental intramuscular buprenorphine to relieve post-thoracotomy pain. In TEA group, 94% of the supplemental drugs were administered during night shifts. These results indicate that IV-PCA of buprenorphine combined with continuous thoracic epidural infusion of bupivacaine is more effective analgesic management than continuous TEA with buprenorphine and bupivacaine.

Disordered expression of inhibitory receptors on the NK1-type natural killer (NK) leukaemic cells from patients with hypersensitivity to mosquito bites

Recent studies have revealed the existence of a distinct type of NK cell leukaemia of the juvenile type, which presents with hypersensitivity to mosquito bites (HMB) as an essential clinical manifestation and is infected with clonal Epstein-Barr virus (EBV). This disorder is thus called HMB-EBV-NK disease and has been reported in Orientals, mostly from Japan. We investigated the profile of cytokine production and the expression of both types of NK inhibitory receptors, i.e. CD94 lectin-like dimers and killer-cell immunoglobulin-like receptors, in NK leukaemic cells from three patients with HMB-EBV-NK disease. It was found that freshly isolated NK leukaemic cells expressed mRNA for interferon-gamma (IFN-gamma) and additionally produced IL-10 upon stimulation with IL-2, indicating that the NK cells were of NK1 type. More than 98% of NK cells from the patients bore CD94 at a higher level than did normal NK cells, whereas p70 or NKAT2, belonging to immunoglobulin-like receptor, was not expressed in those NK cells. Freshly isolated leukaemic NK cells transcribed mRNA for CD94-associated molecule NKG2C at an abnormally high level, and upon stimulation with IL-2 and/or IL-12 they expressed NKG2A as well. The disordered expression of these inhibitory receptors not only provides some insights into the pathogenesis of HMB-EBV-NK disease but also can be used as phenotypic markers for the diagnosis of this type of NK cell leukaemia.

[Utility of Ringer's acetate solution as an intraoperative fluid during cardiovascular surgery with cardiopulmonary bypass]

This study aimed to clarify the difference in the effects of Ringer's acetate (AR) and Ringer's lactate (LR) administration during cardiovascular surgery with cardiopulmonary bypass. We evaluated their effects on intra and postoperative metabolism, liver functions, blood gas and hemodynamic states. Twenty patients were divided into two groups; AR group (n = 10) and LR group (n = 10). Intraoperative serum D-lactate levels in LR group were significantly higher than those in AR group from the beginning of the operation to awakening. Serum acetate levels showed no increase in both groups. The arterial ketone body ratio (AKBR) in AR group was higher than that in LR group, but the difference was not significant. Serum glutamic pyruvic transaminase (GPT) and alkaline phosphatase (ALP) levels in LR group were significantly higher than those in AR group from the induction of the anesthesia. It has been reported that acetate has a greater vasodialatory effect than lactate. However, our findings indicate no significant difference in hemodynamics between the two groups. These results suggest that AR may be more useful than LR during cardiovascular surgery with cardiopulmonary bypass.

Formation of antigenic quinolone photoadducts on Langerhans cells initiates photoallergy to systemically administered quinolone in mice

Quinolone antibacterial agents are well known to cause photoallergy as a side-effect. Murine photoallergy to fluoroquinolones is a T cell-mediated immune response, evoked either by systemic fluoroquinolone and subsequent exposure of skin to ultraviolet A light or by subcutaneous injection of fluoroquinolone-photomodified epidermal cells. In this photosensitivity, epidermal Langerhans cells may be photomodified initially with the drug and thus present photohaptenic moieties to sensitize and restimulate T cells. Although we have shown that Langerhans cells photocoupled in vitro with fluoroquinolones are capable of stimulating sensitized T cells, it remains unclear whether systemically given fluoroquinolone photomodifies Langerhans cells upon ultraviolet A irradiation of the skin and the Langerhans cells become photohapten-bearing, T cell-stimulatory cells. In a murine model of fleroxacin photoallergy induced by intraperitoneal injection of the drugs plus ultraviolet A irradiation of skin, we found that Langerhans cells as well as keratinocytes are photoderivatized with fleroxacin as demonstrated with a fluoroquinolone-specific monoclonal antibody. Langerhans-cell-enriched epidermal cells prepared from mice treated with fleroxacin and ultraviolet A induced proliferation of sensitized T cells, indicating that photomodified Langerhans cells are functional. There was an optimal range of ultraviolet A dose to quantitatively and qualitatively form fleroxacin-photomodified Langerhans cells, as excess ultraviolet A rather reduced the photoantigen-presenting capacity of Langerhans cells presumably because of drug phototoxicity. Our study suggests that Langerhans cells serve as photoantigen-presenting cells in drug photoallergy.

Percutaneous peptide immunization via corneum barrier-disrupted murine skin for experimental tumor immunoprophylaxis

H-2K(b)-restricted tumor epitope peptides, including tyrosinase-related protein 2 residues 181-188 (TRP-2) and connexin 37 residues 52-59 (MUT1), were applied to permeability barrier-disrupted C57BL/6 (B6) mouse skin from which the stratum corneum of the epidermis had been removed by tape-stripping. This procedure primed tumor-specific cytotoxic T lymphocytes (CTLs) in the lymph nodes and spleen, protected mice against subsequent challenge with corresponding tumor cells, and suppressed the growth of established tumors. Preventive and therapeutic effectiveness was correlated with the frequency of tumor-specific CTL precursors. MHC class II Ia(b+) cells separated from tape-stripped skin, compared with those from intact skin, exhibited a strong antigen-presenting capacity for CTL, suggesting that CTL expansion after peptide application is primarily mediated by epidermal Langerhans cells. Thus, percutaneous peptide immunization via barrier-disrupted skin provides a simple and noninvasive means of inducing potent anti-tumor immunity which may be exploited for cancer immunotherapy.

Lymphocyte stimulation test with drug-photomodified cells in patients with quinolone photosensitivity

Quinolone antibacterial agents, known to elicit photosensitive dermatitis as an adverse effect, have both phototoxicity and photoallergenicity. The latter potency is mainly derived from their photohaptenic moiety; quinolones covalently bind to protein and cells upon exposure to ultraviolet A (UVA) light. Our previous study has shown the in vivo and in vitro antigenicity of quinolone-photomodified cells in mice. Here, we examined the presence of sensitized lymphocytes that react with quinolone-photomodified autologous cells in patients with photosensitivity to quinolones. A flow cytometric analysis using a monoclonal antibody specific to quinolone photoadducts demonstrated that peripheral blood mononuclear cells (PBMC) were successfully photomodified with quinolones upon exposure to UVA. PBMC from quinolone-photosensitive patients were cocultured with autologous PBMC photomodified with the causative drug. Modest but significant proliferative responses of responder lymphocytes were found in patients photosensitive to lomefloxacin, fleroxacin, and enoxacin, indicating photoallergic mechanism in these patients. On the other hand, sparfloxacin-photosensitive patients exhibited negative lymphocyte stimulation test, suggesting that its photosensitivity is mainly phototoxic. When UVA-preirradiated quinolones were used as stimulators, only fleroxacin exceptionally stimulated patients' PBMC, indicating its prohaptenic as well as photohaptenic properties. These findings suggest the presence of circulating sensitized T cells in patients with photosensitivity to certain quinolones.

Modulation of T-lymphocyte proliferation by exogenous natural ceramides and sphingosylphosphorylcholine

Sphingolipids such as ceramide and sphingosine are abundantly present in the stratum corneum of epidermis. In atopic stratum corneum, sphingosylphosphorylcholine (SPC) is present in association with a reduction in the amount of ceramides. We have previously shown that the cellular kinetics of T cells are affected by exogenous addition of sphingosine and synthetic ceramides, raising the possibility that sphingolipids diffusing from the stratum corneum modulate skin-infiltrating T cells. By using two natural ceramides and murine T cells, this study further clarified the conditions under which exogenous ceramides enhance the proliferation of T cells. KLH-specific T cell clones 28-4 and 24-2 proliferated in response to natural ceramides when cultured for 44-48 h in the presence of concanavalin A at 1 microg per ml. Elongation of culture periods adversely inhibited the T cell proliferation, suggesting the existence of an optimal exposure time. Augmentation of DNA synthesis by natural ceramides was more pronounced in tumor necrosis factor alpha (TNFalpha)-sensitive 28-4 cells than in less sensitive 24-2 cells, and TNFalpha-induced proliferation of 28-4 cells was suppressed by the concomitant addition of natural ceramides. Similar to ceramides, SPC augmented the proliferation of resting spleen cells. Our study suggests that ceramide modulation of T cell proliferation depends on the TNFalpha sensitivity and activation level of T cells and that SPC also has a mitogenic potential for T cells.

Treatment of T lymphocytes with 8-methoxypsoralen plus ultraviolet A induces transient but biologically active Th1-skewing cytokine production

8-Methoxypsoralen plus ultraviolet A light is suggested to shift T lymphocytes from Th2 to Th1 cells. To clarify this issue, we examined the effects of 8-methoxypsoralen/ultraviolet A on the expression/production of cytokines in peripheral blood mononuclear cells from normal subjects and a Sézary syndrome patient. 8-Methoxypsoralen/ultraviolet A augmented the expression of mRNAs for interferon-gamma and interleukin-2 and reduced those for interleukin-4 and interleukin-10. It seems that this enhancement of Th1 cytokines is caused by increment of cytokine production by Th1 cells but not by conversion of Th2 cells to produce Th1 cytokines. The number of interferon-gamma-secreting lymphocytes was markedly increased in 8-methoxypsoralen/ultraviolet A-treated peripheral blood mononuclear cells 20 h after treatment, whereas that of Th2 cytokine-producing cells was decreased. Accordingly, the amount of interferon-gamma was elevated in culture supernatants from 8-methoxypsoralen-phototreated peripheral blood mononuclear cells, whereas interleukin-4 was significantly reduced. This enhanced production of interferon-gamma, however, was found only until 3 d after 8-methoxypsoralen phototreatment and was declined by 5 d after treatment. Finally, 8-methoxypsoralen/ultraviolet A treatment of T cells regulated their ability to induce keratinocyte CD54 expression. Our results show that 8-methoxypsoralen/ultraviolet A has a transient but biologically active Th1-skewing action in human T cells, suggesting that 8-methoxypsoralen/ultraviolet A exerts a beneficial therapeutic effect on Th2-mediated or Th2-malignant diseases.

Hyporesponsiveness of peripheral blood lymphocytes to streptococcal superantigens in patients with guttate psoriasis: evidence for systemic stimulation of T cells with superantigens released from focally infecting Streptococcus pyogenes

Throat infection with Streptococcus pyogenes is the most important trigger for acute guttate psoriasis. We examined the in vitro responses of peripheral blood mononuclear cells (PBMC) to streptococcal superantigens, SPEA and SPEC, and staphylococcal superantigens, SEB and TSST-1, in patients with guttate psoriasis, in patients with chronic plaque psoriasis, and in healthy subjects. PBMC from patients with guttate psoriasis responded poorly to SPEA and SPEC at concentrations of 0.1 and 1 ng/ml as compared with those from patients with plaque psoriasis, but showed high responses to SEB and TSST-1. The hyporesponsiveness recovered after improvement of the skin eruption. There was no significant difference between guttate and chronic types of psoriasis in the percentage of circulating T-cell receptor BV2 or BV8-bearing T cells, responsive to streptococcal superantigens, indicating that T-cell clonal anergy was a mechanism underlying the hyporesponsiveness. Our results suggest that superantigens released from focally infecting S. pyogenes induce a transient activation of relevant T cells, leading to the development of skin eruption and, subsequently, temporary T-cell anergy to these toxins.

Depletion of IL-10- and TGF-beta-producing regulatory gamma delta T cells by administering a daunomycin-conjugated specific monoclonal antibody in early tumor lesions augments the activity of CTLs and NK cells

It has been demonstrated that gamma delta T cells accumulating in early tumor lesions and those purified from spleen cells of tumor-bearing mice attenuate the activity of CTLs and NK cells. We, therefore, investigated whether depletion of gamma delta T cells from early lesions of tumors results in restoration of CTL and NK cell activities and subsequent regression of tumors. A daunomycin-conjugated anti-gamma delta TCR mAb UC7-13D5 (Dau-UC7) was prepared to efficiently deplete gamma delta T cells. An in vitro study revealed that Dau-UC7 specifically lysed gamma delta TCR+ cells and effectively inhibited splenic gamma delta T cells from tumor-bearing mice to produce cytotoxic cell-suppressive factors. Furthermore, intralesional injections of Dau-UC7 at an early stage of tumor development led to augmentation of tumor-specific CTL as well as NK cell activities and to the resultant regression or growth inhibition of the tumors. On analysis of cytokine profile, gamma delta T cells transcribed mRNAs for IL-10 and TGF-beta, but not IL-4 or IFN-gamma, suggesting the T regulatory 1-like phenotype. Finally, a blocking study with mAbs showed that the inhibitory action of gamma delta T cells on CTLs and NK cells was at least partly mediated by IL-10 and TGF-beta. These results clearly demonstrated the novel mechanism by which T regulatory 1-like gamma delta T cells suppress anti-tumor CTL and NK activities by their regulatory cytokines in early tumor formation.