Impact of Multiplex Polymerase Chain Reaction Test in Patients With Meningitis or Encephalitis

Background

The objective of this study was to evaluate the impact of the FilmArray meningitis/encephalitis panel (FAME) on length of stay (LOS) and duration of antimicrobial treatment in children and adults in a Japanese community hospital.

Methods

This retrospective cohort study was conducted in Japan between January 2016 and December 2022. We included hospitalized patients with cerebrospinal fluid (CSF) samples and those aged <2 months or who had 5 or more white blood cells/μL in the CSF. To compare the days of therapy (DOT) and LOS between the pre-FAME and FAME periods, multivariate Poisson regression analyses were conducted without an offset term.

Results

The number of cases undergoing pathogen-specific polymerase chain reaction increased from 3.7% in the pre-FAME period to 57.5% in the FAME period (P < .001). The pathogen identification rate also increased during the FAME period, from 0.4% to 18.7% (P < .001). While the antibacterial DOT was not statistically different between the 2 periods (adjusted rate ratio [aRR], 1.06 [95% confidence interval {CI}, 1.00-1.13]; P = .063]), the antiviral DOT was significantly shorter in the FAME period (aRR, 0.80 [95% CI, .71-.89]; P < .001).

Conclusions

This study revealed a significant reduction in antiviral use during the FAME period, whereas LOS and antibacterial use did not decrease. Given the possibility of factors (eg, the COVID-19 pandemic) affecting the epidemiology of meningitis and encephalitis, the indications and impact of the FAME test should be evaluated with continuous monitoring of the epidemiology of meningitis and encephalitis and its clinical impact.

Impact of the COVID-19 pandemic and multiplex polymerase chain reaction test on outpatient antibiotic prescriptions for pediatric respiratory infection

This study aimed to evaluate the impact of the prolonged COVID-19 pandemic on outpatient antibiotic prescriptions for pediatric respiratory infections at an acute care hospital in Japan in order to direct future pediatric outpatient antibiotic stewardship. The impact of the COVID-19 pandemic and the FilmArray Respiratory Panel (RP) on outpatient antibiotic prescriptions was assessed from January 2019 to December 2021 using an interrupted time series analysis of children <20 years. The overall antimicrobial prescription rate decreased from 38.7% to 22.4% from the pre-pandemic period to the pandemic. The pandemic (relative risk [RR] level, 0.97 [0.58-1.61]; P = 0.90; RR slope, 1.05 [0.95-1.17] per month; P = 0.310) and FilmArray RP (RR level, 0.90 [0.46-1.75]; P = 0.75; RR slope, 0.95 [0.85-1.06] per month; P = 0.330) had no significant effect on the monthly antibiotic prescription rates. The COVID-19 pandemic was not significantly related to the antibiotic prescription rate, suggesting that it did not impact physicians' behavior toward antibiotic prescriptions. Replacing rapid antigen tests with the FilmArray RP introduced on December 1, 2020, did not affect the magnitude of the reduction in antibiotic prescription rate for pediatric respiratory infections.

Burden of Pediatric Central Nervous System Infection and Cost-Benefit Simulation of Multiplex Polymerase Chain Reaction in Japan

To investigate the clinical use of multiplex polymerase chain reaction (mPCR) in Japan, epidemiological and clinical data for central nervous infections are needed. Here, we report on the epidemiology and economic burden of central nervous system infections and a simulation of the cost-benefit analysis of the Filmarray® Meningitis/Encephalitis (FAME) test for possible clinical use in Japan. We performed FAME tests on samples from 27 patients with pleocytosis aged between 0 and 20 years seen in six community hospitals in Nara and Osaka prefectures. All clinical management procedures were performed without knowledge of the mPCR test results. We analyzed the clinical data and calculated the required reduction in average length of stay for the FAME test to be cost-beneficial. Among the 27 cases, the FAME test revealed causal pathogens in 13 cases (48.1%). The average medical and social costs per case were ¥299,118 ($2,719.2) and ¥171,768 ($1,561.5), respectively. The minimal needed reduction in average length of stay for the FAME test to be cost-beneficial was 0.32- 0.86 days per meningitis case. The result can be informative for evaluating the cost-effectiveness of the clinical use of the FAME test in Japan.

The Epidemiology of Admission-Requiring Pediatric Respiratory Infections in a Japanese Community Hospital Using Multiplex PCR

Respiratory tract infections (RTIs) are the most common diseases globally among children. This study aimed to assess the epidemiology of admission-requiring pediatric RTI cases and evaluate the effect of the pathogen type on the length of hospital stay (LOS) using the FilmArray^® respiratory panel, a multiplex PCR test. The age-specific distribution and seasonality of viruses were investigated between March 26, 2018 and April 12, 2019. Multivariable linear regression analyses were performed to evaluate the effect of pathogen type and coinfection on LOS. Among 153 hospitalized RTI patients, respiratory syncytial virus was the leading cause of hospitalization in infants < 12 months of age (27.7%). Human metapneumovirus and parainfluenza virus were also major causes of hospitalization in patients aged 2-3 years (22.6% and 22.6%, respectively). In the multivariable linear regression model excluding rhinovirus/enterovirus, there was a significant association between viral coinfection and longer LOS (p = 0.012), while single viral infection of any type was not positively correlated with LOS. This study revealed the epidemiology of admission-requiring pediatric RTIs.

The impact analysis of a multiplex PCR respiratory panel for hospitalized pediatric respiratory infections in Japan

Background

Rapid molecular diagnosis of infections has contributed to timely treatments and antimicrobial stewardship. However, the benefit and cost-effectiveness vary in each country or community because they have different standard practices and health care systems. In Japan, rapid antigen tests (RATs) have been frequently used for pediatric respiratory infections. We investigated the impact and cost-effectiveness of a multiplex PCR (mPCR) respiratory panel for pediatric respiratory infections in a Japanese community hospital.

Methods

We replaced RATs with an mPCR respiratory panel (FilmArray®) for admitted pediatric respiratory infections on March 26, 2018. We compared the days of antimicrobial therapy (DOT) and length of stay (LOS) during the mPCR period (March 2018 to April 2019) with those of the RAT period (March 2012 to March 2018).

Results

During the RAT and mPCR periods, 1132 and 149 patients were analyzed. The DOT/case was 12.82 vs 8.56 (p < 0.001), and the LOS was 8.18 vs 6.83 days (p = 0.032) in the RAT and mPCR groups, respectively. The total costs during admissions were ∖258,824 ($2331.7) and ∖243,841 ($2196.8)/case, respectively. Pathogen detection rates were 30.2% vs 87.2% (p < 0.001).

Conclusion

Compared to conventional RATs, the mPCR test contributed to a reduction in the DOT and LOS in a Japanese community hospital for admission-requiring pediatric respiratory infections. However, a proper stewardship program is essential to further reduce the unnecessary usage of antimicrobials.

Questionnaire survey on mumps vaccination for parents in Nara prefecture, Japan

BACKGROUND

Although the mumps vaccine has not been included in the national immunization program (NIP) in Japan, it has been shown that a two-dose routine vaccine program would be highly cost-effective. In this study, we carried outa questionnaire-based study to investigate how many Japanese parents want the mumps vaccine to be included in the NIP with proper information.

METHODS

The questionnaire was given to parents who visited the Pediatrics or neonatal intensive care unit of Nara Prefecture General Medical Center, Nara City, Japan, between 1 March 2017 and 31 August 2017. The questionnaire consisted of information about mumps and six questions, for example (i) do parents know that mumps can be prevented by vaccine; (ii) do they know that they need to pay for mumps vaccines; and (iii) do they hope that the government will resume routine mumps vaccination.

RESULTS

In total, 1,224 parents answered the questionnaire. A total of 81% and 75.4% of parents knew that mumps can be prevented by vaccination and that mumps vaccine is not included in the NIP, respectively, before reading the information. After reading the information, 95.0% of parents thought that mumps vaccine should be included in the NIP. While 61.7% of parents answered that they would choose two-dose vaccination without governmental financial support, 92.1% of them would choose two-dose vaccination with governmental financial support (P < 0.0001).

CONCLUSION

Japanese parents want the mumps vaccine to be included in the NIP. Japan is able to start routine use of the mumps vaccine now.

Static model simulation for routine mumps vaccination in Japan: with a result of mumps-related complications in a Japanese community hospital

Purpose

Mumps vaccine has not been included in the routine national immunization program in Japan, leading to low vaccine coverage rates and periodic epidemics approximately every 5 years. Our hospital (a secondary community hospital in Japan) experienced an increased number of mumps-related complications with a nationwide epidemic in 2016. Using previously reported data and mumps-related cases in our hospital, we estimated the cost-effectiveness of routine mumps vaccination in Japan with a static model using current epidemiologic data.

Materials and Methods

With a decision tree flowchart of mumps infection and adverse events, we estimated the burden of mumps-related complications in our hospital for 5 years, and calculated the current annual national burden. Finally, we compared the current burden and assumptive burden of the stable state after routine vaccination in Japan using a static model.

Results

The cost-benefit ratios with sensitivity analysis were 3.69 (1.08-9.52) and 6.84 (1.51-23.73) in independent inoculation and simultaneous inoculation, respectively, from a social perspective in addition to an annual gain of 9,487 (3,227-14,659) quality adjusted life years.

Conclusion

We contributed additional evidence in terms of cost-effectiveness that routine mumps vaccination should be introduced in Japan with simultaneous inoculation.

Persistent endothelial damage after intravenous immunoglobulin therapy in Kawasaki disease

BACKGROUND

Kawasaki disease (KD) is an acute systemic vasculitis of unknown etiology. Although endothelial cell damage associated with vasculitis might lead to the hypercoagulability that is involved in coronary artery disease, the changes in coagulation after intravenous immunoglobulin therapy (IVIG) have not been well investigated in KD. The aims of this study were to address the changes in coagulation before and after IVIG in KD, and to further elucidate the coagulation-inflammation axis, with special attention to endothelial damage.

METHODS

We retrospectively collected the laboratory data before and after IVIG in 26 pediatric KD patients treated at the Nara Prefecture Western Medical Center between May 2010 and April 2012. Prothrombin time (PT), activated partial thromboplastin time (APTT) and levels of fibrin/fibrinogen degradation products (FDP) and D-dimer were assessed as coagulation markers. Fibrinogen, ferritin, serum amyloid A, procalcitonin and urine β2 microglobulin were assessed as inflammation markers. Thrombomodulin, antithrombin, factor VIII activity (FVIII:C), and von Willebrand factor antigen (VWF:Ag) were used to assess endothelial damage.

RESULTS

Prolonged PT and APTT before IVIG were significantly shortened after IVIG, and elevated levels of FDP and D-dimer were significantly decreased. Elevated levels of inflammation markers had decreased significantly after IVIG, but levels of FVIII:C and VWF:Ag remained high, even after IVIG.

CONCLUSIONS

Ameliorated inflammation by IVIG might improve the hypercoagulable state. Nevertheless, our results suggest that endothelial damage might be prolonged in IVIG-treated patients. Control of endothelial damage in KD is critical.

[Emergency operation for traumatic thoracic aortic rupture diagnosed by enhanced chest computed tomography; report of a case]

Thoracic aortic injury caused by blunt chest trauma is often fatal. Although aortography had been inevitable for thoracic surgery until recently, image of computed tomography (CT) is often superior to aortogram nowadays. We present a case of 64-yaer-old man with blunt chest trauma by traffic accident, who was successfully diagnosed and operated without invasive aortography. Thoracic aortic rupture was suspected by plain chest X-ray. His enhanced CT showed the localized leakage of contrast media near the arterial ligament of aortic arch. Because his condition was critically ill, operation was performed immediately without aortography. There found Y-shaped tear at the distal aortic arch, and was replaced with a prosthetic graft. Operation was performed under left heart bypass using heparin-coated circuit and centrifugal pump. We would stress that the enhanced chest CT is sufficiently diagnostic in thoracic aortic trauma like the present case.

[A successful treatment for myonephropathic metabolic syndrome after operation of acute aortic dissection (Stanford type A) with multiple organ ischemia]

A 60-year-old man had sudden chest pain and right lower extremity pain. A diagnosis of acute aortic dissection (Stanford type A) with right lower extremity ischemia was made. An emergency ascending aortic and total arch replacement, right axillo-femoral bypass, and coronary artery bypass grafting was performed for acute aortic dissection, acute right iliac arterial occlusion, and acute myocardial infarction. Myonephropathic metabolic syndrome (MNMS) occurred 2 days after operation. The serum creatine kinase value increased over 68,000 U/l, hemodiafiltration was started on the 2nd postoperative day (POD). The patient fell into anuric state and hemodiafiltration was performed 3 times a week. Urination was obtained over 1,000 ml/day from the 25th POD and hemodiafiltration was not necessary any more. We emphasize that prompt operation including revascularization of ischemic leg should be performed in acute aortic dissection with extremity ischemia and also prompt hemodiafiltration to improve the prognosis of these disastrous lesion.

[Electroencephalographic characteristics during maintenance and emergence from propofol-ketamine-fentanyl anesthesia]

Spectral edge frequency 90 (SEF 90) and relative power in four frequency bands (beta, alpha, theta, delta) of the processed electroencephalogram were recorded in 20 patients undergoing elective gynecological surgery under total intravenous anesthesia (propofol-ketamine-fentanyl) (group PKF, n = 10) or nitrous oxide-oxygen-isoflurane (group GOI, n = 10) anesthesia. During anesthesia, mean SEF 90 and relative beta power increased more significantly in group PKF than in group GOI. At emergence from anesthesia, SEF 90 was 21.8 Hz in group PKF and 20.5 Hz in group GOI. These results suggest that it is difficult to evaluate the depth of anesthesia using pEEG under PKF anesthesia.

[A new method of continuous propofol infusion for total intravenous anesthesia]

Total intravenous anesthesia (TIVA) is recommended to avoid air pollution. However, intermittent administration of anesthetic agents has a large disadvantage of delayed emergence time. We suggested continuous TIVA with propofol, ketamine, vecuronium and buprenorphine (PKBp), and reported that maintenance with continuous intravenous administration of propofol corresponding to the age associated with ketamine (240 micrograms.kg-1.h-1), vecuronium (80 micrograms.kg-1.h-1) and buprenorphine (0.4 microgram.kg-1.h-1) brought rapid emergence and that the last 1/6 of anesthetic time was the point to reduce propofol maintenance dose. In this study, we maintained anesthesia with continuous intravenous administration of propofol using twice step down method every one hour. We conclude that the reduction of propofol maintenance dose for every 1/6 in one hour produces fewer dropout cases.

[Continuous total intravenous anesthesia is recommended for wake-up test]

Total intravenous anesthesia (TIVA) has been recommended in view of avoiding air pollution. However, intermittent administration of anesthetic agents has a large disadvantage of delayed emergence time. We reported that continuous TIVA with propofol, ketamine, vecuronium and buprenorphine (PKBp) could bring rapid emergence time. An 8-year old female with spinal scoliosis underwent spinal instrumentation under continuous TIVA. Wake-up test was done twice during surgery smoothly after stopping infusion of anesthetic agents in the cocktail. We conclude that continuous TIVA is one of the most recommended anesthetic methods for wake-up test.

[A clinical dose finding study of propofol in continuous total intravenous anesthesia]

Total intravenous anesthesia (TIVA) is recommended in view of avoiding air pollution. However, intermittent administration of anesthetic agents has a disadvantage of delayed emergence time. We have suggested continuous TIVA with propofol, ketamine, vecuronium and buprenorphine (PKBp), and reported that the elder or the patients anesthetized for a long time show delayed emergence from continuous TIVA. In this study, after induction with propofol, ketamine, vecuronium and buprenorphine, the subjects were maintained with continuous intravenous administration of propofol corresponding to the age using twice step down method with ketamine (240 micrograms.kg-1.h-1), vecuronium (80 micrograms.kg-1.h-1) and buprenorphine (0.4 microgram.kg-1.h-1). Emergence was evaluated from the 2nd step down of propofol to awareness. There was a linear relationship between the emergence (2nd step down time of propofol to awareness) (Y) and the anesthetic time (X); Y = 0.175X + 3.00. We conclude that the last 1/6 (= 0.175) of anesthetic time is the point to reduce maintenance doses of propofol to achieve more rapid emergence.

[Economical benefit of continuous total intravenous anesthesia]

Total intravenous anesthesia (TIVA) has been recommended in view of avoiding air pollution. However, intermittent administration of anesthetic agents has a large disadvantage of delayed emergence. We reported that continuous TIVA with propofol, ketamine, vecuronium and buprenorphine (PKBp) could bring rapid emergence. In this study, we calculated and compared the cost of anesthesia in the subjects who had undergone general anesthesia either with continuous PKBp or nitrous oxide-oxygen-sevoflurane. In group PKBp subjects, after induction with propofol, ketamine, vecuronium and buprenorphine, anesthesia was maintained with continuous intravenous administration of propofol corresponding to the patient's age using twice step down method; ketamine (240 micrograms.kg-1.h-1), vecuronium (80 micrograms.kg-1.h-1) and buprenorphine (0.4 microgram.kg-1.h-1). Group GOS subjects, after the same induction method, received nitrous oxide, sevoflurane and vecuronium. Moreover, the group GOS subjects were divided to two groups; the high flow GOS (N2O:O2:sevoflurane = 4 l:2 l:30 ml) and the low flow GOS (N2O:O2:sevoflurane = 2 l:1 l:15 ml). Continuous PKBp group showed lower cost than the high flow GOS group. The PKBp group showed lower cost than the low flow GOS group except in patients weighing more than 100 kg. Furthermore, we calculated the cost of continuous PKBp anesthesia in Japan, U.S.A. and U.K. The U.S.A. cost of PKBp was higher than the Japanese and the U.K., because the cost of ketamine in U.S.A. is higher than in the other countries. Continuous PKBp is more economical than the high flow GOS, and continuous PKBp in Japan is more economical than in U.S.A.

[Early postoperative results of coronary revascularization with the radial artery: an analytical study of vascular diameter ratio of the graft and the coronary artery]

Between October 1996 and June 1988, radial artery grafts were used in 49 patients undergoing myocardial revascularization. There were three hospital deaths, none of them due to the use of radial artery. In 32 patients studied early, 33 of 34 radial artery grafts were patent (patency 97%), and 30 of 32 internal thoracic artery grafts (94%), 32 of 35 saphenous vein grafts (90%), 3 of 3 gastroepiploic artery grafts (100%) were patent respectively. The mean diameter ratio of graft and recipient coronary artery was 1.03 +/- 0.17 in radial artery, 0.92 +/- 0.16 in internal thoracic artery and 1.67 +/- 0.55 in saphenous vein graft. Our result suggest that the radial artery is an excellent conduit for myocardial revascularization, although a longer follow-up is mandatory.

[Continuous total intravenous anesthesia is useful for postoperative pain management]

We compared postoperative pain in two groups. All anesthetic agents were continuously administered intravenously in a continuous PKF (propofol 2-10 mg.kg-1.h-1, ketamine 240 micrograms.kg-1.h-1 and fentanyl 0.4 microgram.kg-1.h-1) group. In a control group, anesthesia was maintained by GOI (N2O-oxygen-isoflurane). Twenty-two patients scheduled for gynecological lower abdominal surgeries were divided into the continuous PKF group (n = 11) and the GOI group (n = 11). Epidural anesthesia was employed in both groups, using local anesthetic agents and fentanyl during surgeries and for 24 hrs postoperatively. To evaluate pain, VAS and Prince Henry Score on rest, cough and movement were taken 2 hrs and 5 hrs postoperatively, and in the morning and afternoon of the 1st as well as 2nd postoperative days. The continuous PKF group showed lower scores than the GOI group. It is a great advantage to use continuous PKF for postoperative pain management, and our data indicate that low dose ketamine may induce pre-emptive analgesia.

[Anesthetic management by continuous total intravenous anesthesia]

Total intravenous anesthesia (TIVA) is one of the most recommended methods of anesthesia for the prevention of air pollution. But the intermittent administration of anesthetic agents has a disadvantage of elongating emergence time. When inexperienced residents undertake TIVA with larger doses of drugs to stabilize vital signs, it takes long emergence time. Therefore, we suggested a continuous TIVA with propofol, ketamine and vecuronium in combination with butorphanol (PKBt) or buprenorphine (PKBp). In this study, we compared emergence times in the subjects, who underwent general anesthesia with PKBt and PKBp. After induction with propofol (2 mg.kg-1), ketamine (0.5 mg.kg-1), vecuronium (0.1 mg.kg-1) and agonist-antagonist opioids, subjects in each group were maintained with continuous intravenous injection of propofol (2-10 mg.kg-1.h-1), ketamine (240 micrograms.kg-1.h-1) and vecuronium (80 micrograms.kg-1.h-1) in combination with butorphanol (8 micrograms.kg-1.h-1) or buprenorphine (0.4 microgram.kg-1.h-1). The emergence times were designated as Op time (the end of operation to awareness), Pr time (the end of propofol to awareness), and B time (the end of butorphanol or buprenorphine to awareness). The emergence times of Op, Pr and B were not different between the groups. The elderly patients showed longer B time than the younger. The patients with long anesthetic time showed longer B time than the patients with short anesthesia. The patients with general anesthesia combined with epidural anesthesia showed longer B time than the patients with only general anesthesia. But there were no differences in Op time and Pr time. We conclude that the continuous TIVA is useful to reduce emergence time and prevent air pollution.

Characterization of nociceptin hyperalgesia and allodynia in conscious mice

1. Intrathecal (i.t.) administration of nociceptin and high doses of morphine induced allodynia in response to innocuous tactile stimuli, and i.t. nociceptin evoked hyperalgesia in response to noxious thermal stimuli in conscious mice. Here we have characterized the nociceptin-induced allodynia and compared it with the morphine-induced allodynia and the nociceptin-evoked hyperalgesia. 2. Nociceptin-induced allodynia was evoked by the first stimulus 5 min after i.t. injection, reached a maximum at 10 min, and continued for a 50 min experimental period. Dose-dependency of the allodynia showed a bell-shaped pattern from 50 pg to 5 ng kg-1, and the maximum effect was observed at 2.5 ng kg-1. 3. Morphine-induced allodynia reached the maximum effect at 15 min and declined progressively until cessation by 40-50 min. The dose-response curve showed a bell-shaped pattern, similar to that induced by nociceptin, with a maximum effect at 0.5 mg kg-1, five orders of magnitude higher than that of nociceptin. 4. The allodynia evoked by nociceptin and morphine were dose-dependently blocked by glycine, D(-)-2-amino-5-phosphonovaleric acid (D-AP5, an N-methyl-D-aspartate (NMDA) receptor antagonist), gamma-D-glutamylaminomethyl sulphonic acid (GAMS, a non-NMDA receptor antagonist) and methylene blue (a soluble guanylate cyclase inhibitor), but were not affected by muscimol (a gamma-aminobutyric acidA (GABAA) receptor agonist) and baclofen (a GABAB receptor agonist). 5. Morphine did not inhibit forskolin-stimulated cyclicAMP formation in cultured cells expressing the nociceptin receptor. 6. Nociceptin-induced hyperalgesia was evoked 10-15 min after i.t. injection. Nociceptin produced a monophasic hyperalgesic action over a wide range of doses from 5 fg to 50 ng kg-1. The nociceptin-induced hyperalgesia was blocked by glycine only among the agents examined. 7. None of the pain responses evoked by nociceptin and morphine were blocked by naloxone. 8. These results demonstrate that, whereas the mechanisms of the nociceptin-induced allodynia and hyperalgesia are evidently distinct, they involve a common neurochemical event beginning with the disinhibition of the inhibitory glycinergic response. Morphine may induce allodynia through a pathway common to nociceptin, but the nociceptin receptor does not mediate the action of high doses of morphine.

[Surgical correction of an incomplete endocardial cushion defect in a 66-year-old male with the remarkable pulmonary hypertension]

A surgical case of a 66-year-old male with an endocardial cushion defect (ECD) is reported. He had preoperative pulmonary hypertension (80/25 mmHg, Pp/Ps 0.61), hypoxia (63.7 mmHg) and decreased creatinin clearance (45.7 ml/min). Respiratory condition was New York Heart Association's (NYHA's) grade III. Angiocardiography showed a typical gooseneck deformity associated with mitral and tricuspid valve regurgitations with the cleft (Seller's grade II and III). As surgical correction, direct suture of the cleft in an anterior leaflet with mitral annuloplasty, patch closure of the ostium primum defect with Xenomedical patch and tricuspid annuloplasty were performed. Postoperative data were restored to NYHA grade I. decreased pulmonary artery pressure (43/21 mmHg) and resistances (Pp/Ps 0.36). The only three surgical treatments of an incomplete ECD were reviewed in over 65-year-old patients in Japan included one perioperative death. Although we suggest it should be actively taken surgical repair even in elderly patients with pulmonary hypertension.

[Postoperative pain relief for a patient with elective mutism by patient controlled analgesia]

We previously reported that intrathecal (i.t.) administration of morphine reduced postoperative pain in pediatric patients after spinal instrumentation for scoliosis (Cotrel-Dubousset method), and the i.t. administration of morphine before incision produced better pain relief than that given after the surgical procedure. In this study, we evaluated postoperative pain relief in a patient with elective mutism who had been given i.t. morphine 0.15 mg before surgery. The patient was scheduled to undergo patient controlled analgesia (PCA) intravenously with morphine after surgery. The grade of postoperative pain and incidence of side effects were assessed at 1, 2, 6, 12, 24, and 48 h after the operation. The pain was rated by means of a verbal numeric rating scale (0-3) and a visual analog scale (VAS) (0-100mm). The used morphine volume shown on a PCA device was evaluated at scheduled times. No patient developed hemodynamic instability or respiratory depression during the monitoring period. We conclude that PCA can be useful for the patient with elective mutism.

[Coronary artery bypass grafting for acute myocardial infarction]

Five hundred and fourteen cases with acute myocardial infarction were admitted to our hospital during the past 5 years, since April 1990. Among 343 cases who had emergency coronary angiography, 53 cases had coronary artery bypass grafting surgery within 2 weeks after the onset of acute myocardial infarction. Mean number of bypass grafts was 2.9 +/- 0.9/patient, and operative mortality was 25% (13/53). Clinical condition immediately before the surgery and surgical mortality was, shock state in 20 cases (mortality 50%), IABP dependent state in 23 cases (mortality 13%), post-infarction angina in 8 cases (mortality 0%). Mortality in 8 cases whose infarct-related artery was left main trunk was as high as 63%. Eight of 9 cases whose cardiac indices were below 2.01/min/m2 immediately after the surgery died of pump failure. On the contrary, only 2 of 37 cases whose post-operative cardiac indices were above 2.01/min/m2 died of non-cardiac reason. To improve the surgical results, we concluded that powerful mechanical support such as ventricular assist system should be applied to post-operative pump failure cases whose cardiac indices were below this limit despite the aid of IABP.

Involvement of glutamate receptors in strychnine- and bicuculline-induced allodynia in conscious mice

BACKGROUND

Glycine and gamma-aminobutyric acid (GABA) are inhibitory neurotransmitters that appear to be important in sensory processing in the spinal dorsal horn. Intrathecal administration of strychnine (strychnine-sensitive glycine receptor antagonist) or bicuculline (GABAA antagonist) was reported to induce allodynia. Although the strychnine-induced allodynia was shown to be mediated through the N-methyl-D-aspartate (NMDA)-type glutamate receptor, it is not clear whether the bicuculline-evoked-allodynia is mediated through the glutamate receptor system or how different the allodynia induced by strychnine and bicuculline are.

METHODS

Male ddY mice weighing 20 +/- 2 g were used in this study. A 27-G stainless-steel needle attached to a microsyringe was inserted between the L5 and L6 vertebrae by a slight modification of the method of Hylden and Wilcox. Drugs in vehicle were injected slowly into the subarachnoid space to conscious mice at 22 +/- 2 degrees C. The volume of the intrathecal injection was 5 microliters. Studies on allodynia were carried out essentially according to the method of Yaksh and Harty.

RESULTS

The intrathecal administration of strychnine or bicuculline in conscious mice resulted in allodynia elicited by nonnoxious brushing of the flanks. The maximum allodynia induced by strychnine was observed 5 min after intrathecal injection, but that induced by bicuculline was observed 10 min after intrathecal injection. Both responses gradually decreased over the experimental period of 50 min. The allodynia induced by strychnine was dose-dependently relieved by NMDA receptor antagonists (D-AP5, ketamine, and 7-C1-KYNA) and non-NMDA receptor antagonists (GAMS and CNQX) but not by metabotropic receptor antagonists (L-AP3 and L-AP4). On the other hand, allodynia induced by bicuculline was dose-dependently relieved by GAMS, L-AP3, and L-AP4, but not by D-AP5, ketamine, 7-C1-KYNA, and CNQX. Whereas the strychnine-evoked allodynia was dose-dependently relieved by the nitric oxide synthase inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME) and the soluble guanylate cyclase inhibitor methylene blue, the bicuculline-induced one was dose-dependently relieved by methylene blue but not by L-NAME.

CONCLUSIONS

These results demonstrate that both strychnine- and bicuculline-evoked allodynia were mediated through pathways that include the glutamate receptor and nitric oxide systems but in a different manner. the current study suggests that GABA and glycine may modulate responses to an innocuous tactile stimulus as inhibitory neurotransmitters at presynaptic and postsynaptic sites in the spinal cord, respectively.

L-NAME, an inhibitor of nitric oxide synthase, blocks the established allodynia induced by intrathecal administration of prostaglandin E2

We recently reported that intrathecal (i.t.) administration of prostaglandin E2 (PGE2) to conscious mice induced allodynia, a state of discomfort and pain evoked by innocuous tactile stimuli. In the present study, we examined the effect of the PGE receptor EP1 subtype antagonist ONO-NT-012, the N-methyl-D-aspartate (NMDA) receptor antagonist MK-801, and the NO synthase inhibitor N omega-nitro-L-arginine methyl ester (L-NAME) on the allodynia. The PGE2-induced allodynia was blocked by simultaneous i.t. injection of ONO-NT-012, MK-801, or L-NAME. However, 5 min after i.t. injection of PGE2, the allodynia was significantly blocked by i.t. L-NAME, but not by i.t. ONO-NT-012 or MK-801. These results demonstrate that the PGE2-induced allodynia, once developed, does not require the continued agonist occupancy of EP1 and NMDA glutamate receptor sites.

[Use of Finapres during warming for postoperative patients]

We used Finapres during rewarming after extracorporeal circulation in 16 patients who underwent cardiac surgery. In patients with passive rewarming there were no differences in blood pressure measured with a Finapres and that by an invasive monitor. On the other hand, in patients rewarmed with the aid of nitroglycerin, there were statistically significant differences between blood pressures measured with indirect and direct methods.

[Acute aortic dissection due to cross-clamp injury during coronary artery bypass grafting--a report of successfully repaired case]

A case with successfully repaired acute aortic dissection due to cross-clamp injury during coronary bypass surgery was reported. A 54-year-old man had usual coronary artery bypass surgery by using 3 saphenous vein grafts (4 distal anastomosis). Immediately after the completion of cardiopulmonary bypass, acute aortic dissection, which was caused by aortic cross-clamp, was noted. Cardiopulmonary bypass was resumed and the injured ascending aorta was replaced with prosthetic graft under profound hypothermia and circulatory arrest. An "Island flap" of the ascending aorta (3 x 4 cm in diameter), containing 3 proximal anastomotic positions of vein grafts, was excised from the aortic wall, and was re-implanted into the frontal wall of the aortic prosthesis. The patient well tolerated the operative procedure, and fully recovered from the serious condition after 6 days of IABP support and 11 days of inotropic support. He is doing quite well one year after the surgery. This case is believed to be the first reported one of such reconstructive method for acute aortic dissection during the coronary bypass surgery.

Congenital ventricular aneurysm and diverticulum in children

Clinical profiles were analysed of 18 children with congenital ventricular aneurysm (CVA) and diverticulum (CVD) (nine with CVA and nine with CVD). Of 18 children, only six had any symptoms, consisting of chest discomfort, palpitation, or convulsion. Heart murmurs were heard in nine of the 18 children, and a nonspecific systolic ejection murmur in one. A systolic click was heard in only four children. Dyskinesia of an abnormal protrusion of the cardiac silhouette on the chest x-ray film was detected in only three. The ECG revealed abnormal findings in all children. In those with CVA, signs of myocardial damage or left axis deviation (LAD) and left bundle branch block (LBBB) were the main findings. Among those with CVD, multiple premature ventricular contractions (PVCs) were present in four; some signs of myocardial damage were present in three. None of those with CVD had LAD or LBBB. Among the four children with right ventricular diverticulum, multiple PVCs were present in three. The lesions were detected by two-dimensional echocardiography (2DE) before angiography in 13 (72%) of 18 children. The wall kinetics of the lesions, as seen on 2DE, were in agreement with the subsequent angiographic findings.