Rupture of pyogenic liver abscess

OBJECTIVE

Our objective was to study the clinical manifestations, course, treatment, and results obtained in 23 patients with ruptured pyogenic liver abscess and compare these findings with those of nonruptured cases.

METHODS

Four hundred twenty-four patients with clinical diagnoses of pyogenic liver abscess were enrolled in the study. Among these, 23 patients had ruptured pyogenic liver abscess. The clinical manifestations, incidence of septic shock, laboratory findings, concurrent diabetes mellitus, etiology of abscess, and results of the treatment were recorded. Qualitative data were analyzed by chi 2 test, and quantitative data were analyzed by Student's t test.

RESULTS

Except for abdominal pain and septic shock, other symptoms, such as fever, chills, and jaundice, were similar in ruptured and nonruptured groups. Laboratory findings indicated that the group with ruptured liver abscess had higher levels of bilirubin, blood glucose, and aspartate aminotransferase than the non-ruptured group. Of the patients with ruptured abscess, 14 (60.9%) had diabetes mellitus and 15 (65.2%) were cryptogenic. Klebsiella pneumoniae was the bacteria most often isolated in both blood cultures and liver aspirates. Surgical intervention--draining the abscess and cleaning the abdominal cavity--was the only means of saving the patients' lives. The overall mortality rate was higher in this group (43.5%) than in the nonruptured group (15.5%).

CONCLUSIONS

Ruptured pyogenic liver abscess should be suspected if septic shock and diffuse abdominal pain are found in a patient with pyogenic liver abscess, concurrent with high levels of bilirubin, aspartate aminotransferase, and blood glucose. Surgery is the only treatment for this condition.

Vecuronium dissolved in normal saline exaggerates pain on intravenous injection

BACKGROUND

On some anesthetic occasions, many patients complained of pain at the site of injection when vecuronium, dissolved in normal saline, was administered intravenously. The aims of this study was to compare the incidence of pain on i.v. injection of vecuronium either dissolved in normal saline or in a solvent provided by the pharmaceutical manufacturer.

METHODS

We studied eighty patients of ASA physical status class I-II undergoing elective surgery under general anesthesia. Patients were arranged randomly to receive intravenous 0.1 mg/kg vecuronium dissolved either in solvent (n = 40) or in normal saline (n = 40) through the catheter indwelling in a vein on the dorsum of hand over 5 seconds. Immediately after injection, a nurse was appointed to score the degree of pain. Induction of anesthesia was accomplished with thiopental and fentanyl 30 seconds after vecuronium administration.

RESULTS

Vecuronium dissolved in normal saline induced severe pain more frequently during injection than that dissolved in solvent (27.5% versus 10%). There was no significant difference in pH between these two solutions (3.87 versus 4.08). However, vecuronium dissolved in normal saline showed higher osmolality than that dissolved in solvent (425 +/- 7 mOsm/kg versus 149 +/- 3 mOsm/kg).

CONCLUSIONS

Pain resulting from intravenous injection of vecuronium can be aggravated if normal saline was used as the solvent. Increased osmolality may also be responsible for this phenomenon.

The comparison of clinical course and results of treatment between gas-forming and non-gas-forming pyogenic liver abscess

OBJECTIVES

To study and review the clinical manifestations, courses, and results of treatment in 83 cases of verified gas-forming pyogenic liver abscess.

DESIGN

Case series.

SETTING

Both primary and referral hospital care.

PATIENTS

Four hundred twenty-four patients with clinical diagnosis of pyogenic liver abscess were enrolled in the study. Eighty-three patients had gas-forming abscesses and 341 had non-gas-forming abscesses. The clinical manifestations, duration of symptoms, incidence of septic shock, laboratory findings, concurrent diabetes mellitus, cause of abscess, size of abscess, and results of treatment were recorded.

MAIN OUTCOME MEASURES

A chi 2 test for qualitative data and Student's test for quantitative data.

RESULTS

Duration of symptoms were shorter (mean +/- SD, 5.2 +/- 5.3 vs 7.6 +/- 10 days) (P < .005) and the incidence of septic shock was higher in the gas-forming than in the non-gas-forming group (32.5% vs 11.7%) (P < .01). Laboratory findings revealed high levels of blood glucose, aspartate aminotransferase, alkaline phosphatase, and serum urea nitrogen in the gas-forming group. The size of abscess was usually bigger (> 5 cm) in this group. In the gas-forming group, 71 patients (85.5%) had diabetes mellitus and 65 patients (78.3%) had conditions of cryptogenic origin. Klebsiella pneumoniae was the main bacteria, in blood culture and liver aspirates, especially in gas-forming liver abscess. Medical treatment and/or aspiration carried a high mortality rate (44.4%) in the gas-forming group; also, the overall mortality rate was higher in this group than in the non-gas-forming group (27.7% vs 14.4%) (P < .01).

CONCLUSIONS

The gas-forming liver abscess may be a disease of wide spectrum of severity and may run a fulminating course. Strong antibiotics with early adequate drainage are mandatory. Surgery should not be delayed if necessary.

The physiological effect of CO2 pneumoperitoneum in pediatric laparoscopy

BACKGROUND

The physiological effect of CO2 pneumoperitoneum during laparoscopy is a great concern of the anesthesiologists. Its effect in pediatric laparoscopy has not been previously reported. The purpose of this study was to examine the physiological alteration of pediatric patients during CO2 pneumoperitoneum.

METHODS

One hundred and twenty six children aged from 11 mon to 13 yr undergoing laparoscopic inguinal exploration were divided into three groups based on age orientation: group I comprising 40 children with age from 11 mon to 2 yr; group II 46 children with age between 2 to 5 yr; and group III 40 children aged from 5 to 13 yr. All patients received endotracheal anesthesia with halothane-N2O in 50% O2 and atracurium for muscle relaxation. Respiration was controlled by an Ohmeda 7000 ventilator with constant minute ventilation to maintain baseline end-tidal CO2 tension (PETCO2) between 32-33 mmHg. After anesthesia, CO2 was insufflated into the peritoneal cavity via the opened hernia sac. The intraabdominal pressure exerted by CO2 was 10 mmHg and the duration of pneumoperitoneum and laparoscopy was 15 min. We recorded airway pressure, PETCO2, body temperature, blood pressure, heart rate, heart rhythm, and oxygen saturation simultaneously at 1 min interval before, during, and after laparoscopy.

RESULTS

The airway pressure and PETCO2 showed significant increases during laparoscopy (15-18% and 18-20% respectively) in all cases, but the percentage of increases were not significantly different among groups. However, the PETCO2 change in terms of time lag were different between groups: (1) the time lag from CO2 insufflation to the emergence of PETCO2 change (latent period) was respectively 0.7 +/- 0.1 (mean +/- SD) min in group I, 0.9 +/- 0.2 min in group II and 1.5 +/- 0.2 min in group III (p < 0.05); (2) the PETCO2 change from baseline to a plateau (ascending period) was respectively 4.2 +/- 0.6 min in group I, 6.3 +/- 1.0 min in group II and 9.1 +/- 1.1 min in group III (p < 0.05); (3) the PETCO2 decline from plateau to baseline after CO2 deflation (descending period) was respectively 6.2 +/- 0.5 min in group I, 8.3 +/- 0.8 min in group II and 12.0 +/- 1.3 min in group III (p < 0.05). The body temperature and hemodynamics including blood pressure, heart rate, heart rhythm, oxygen saturation were not significantly changed during laparoscopy in all groups.

CONCLUSIONS

The changes of PETCO2 during laparoscopy did not influence the hemodynamic stability in our study. The younger children give a faster reaction time of PETCO2 change after CO2 insufflation than do the older children which may be related to the variation of physiological exhibition at different state of development.

Magnetic resonance imaging of siderotic hepatic adenoma

This is a case report of a patient with hepatic adenoma who had a magnetic resonance imaging (MRI) appearance mimicking that of adenomatous hyperplasia. The adenoma was hyperintense on T1-weighted image (T1WI) and hypointense on T2-weighted image (T2WI). Pathologically, iron deposition in hepatocytes and Kupffer cells was proved by Prussian blue stain that caused hypointensity on T2WI. Iron deposition in hepatic adenomatous hyperplasia has been documented in the past, but there are no reports of siderotic adenoma in the literature. We suggest that siderotic hepatic adenoma be included in the differential diagnosis when MRI appearance is hyperintense on T1WI and hypointense on T2WI.

Treatment of postoperative residual hepatolithiasis after progressive stenting of associated bile duct strictures through the T-tube tract

PURPOSE

The authors report their experience with the treatment of intrahepatic bile duct strictures associated with hepatolithiasis.

METHODS

Eighty patients had multiple postoperative retained intrahepatic duct stones trapped behind intrahepatic biliary strictures. Before stone extraction, the strictures were opened gradually by semirigid dilators, followed by stent placement to create enough patency for stone removal. All procedures were carried out through the T-tube tracts and were aided by cholangioscopy and electrohydraulic lithotripsy.

RESULTS

Complete clearance of stones was achieved in 69 patients. Failure to dilate the strictures was due to acute and multiple ductal angulations. These included the right posterior inferior intrahepatic duct at its junction with the left intrahepatic ducts when it was more than 2 cm distal to the hepatic bifurcation, when the angle between the T-tube tract and the common bile duct was smaller than 90 degrees, and when stones were located in peripheral intrahepatic ducts with more than five angulations.

CONCLUSION

This technique is considered safe and effective for complicated hepatolithiasis with intrahepatic biliary strictures.

Gonadotropin releasing hormone (GnRH) agonist induces down-regulation of the CD3+CD25+ lymphocyte subpopulation in peripheral blood

PROBLEM

To test whether GnRH agonist could alter in vivo human immune cells and whether the alteration is related to the success of pregnancy in an in vitro fertilization-embryo transfer (IVF-ET) program.

METHODS

Thirty-six infertile patients were enrolled under the long protocol of GnRH agonist (buserelin acetate) and superovulation with gonadotropin from our IVF-ET program. Peripheral B cells, NK cells, CD4+ and CD8+ T cells, and the expression of CD69, CD25, HLA-DR, and CD71 antigens on the T cells were serially examined by dual-color flow cytometry.

RESULTS

B cells, NK cells, CD8+ T cells, and CD71+ T lymphocyte subpopulations were not changed throughout the whole course of treatment. CD4+ T cell and CD25+ T cell subpopulations were significantly down-regulated when the GnRH agonist was used for approximately 2 wk. CD3+CD69+, CD3+CD25+, and CD3+DR+ lymphocyte subpopulations were increased at 7 days (during implantation) and at 14 days after embryo transfer in pregnant patients, but not in patients who failed to get pregnant.

CONCLUSIONS

The GnRH agonist had a transiently immunosuppressive effect on CD4+ and CD25+ T cells, but CD69+, CD25+, and HLA-DR+ T cells were activated during and after successful implantation.

Correlation between sperm morphology using strict criteria in original semen and swim-up inseminate and human in vitro fertilization

To study the value of sperm morphology using strict criteria in raw semen and in swim-up inseminate of human in vitro fertilization (IVF), 135 cycles of IVF with normal sperm concentration and motility were recruited. At least two mature oocytes were recovered in each cycle. The correlation between the percentages of normal forms and fertilization rates of mature oocytes was analyzed. The results demonstrate that the percentage of normal forms in both the raw semen and swim-up sample of patients with poor fertilization was significantly lower than in those with acceptable fertilization. The percentages of normal forms both in raw semen and in swim-up sample were significantly correlated with fertilization rates in vitro, however, the former seemed to have a better correlation (r = .51 and .19, respectively). Regarding the percentages of normal forms in raw semen, the fertilization rate in patients with normal forms < 4% was 6 +/- 11%, for 4-14% it was 58 +/- 36%, and for > 14% it was 88 +/- 20%. The fertilization rates were significantly different among these three groups of patients. The evaluation of sperm morphology using strict criteria in raw semen before IVF is predictive of fertilization outcome and may also help doctors to choose an optimal method of treatment for patients.

Ductal dilatation and stenting make routine hepatectomy unnecessary for left hepatolithiasis with intrahepatic biliary stricture

BACKGROUND

Hepatolithiasis with intrahepatic biliary strictures, more common in Southeast Asia than elsewhere, remains a difficult problem to manage. Hepatic resection has recently been advocated as one of the treatment modalities for hepatolithiasis; however, this procedure is not without risk. This study was designed to achieve complete clearance of the stones, eliminate bile stasis, and avoid the potential risks of hepatic resection in the patient with hepatolithiasis and intrahepatic biliary stricture.

METHODS

In this prospective clinical trial 13 patients with retained left hepatolithiasis and intrahepatic biliary strictures were included. All the patients met the following criteria: (1) initial surgical procedure for hepatolithiasis, (2) normal gross findings of the left liver, and (3) no obvious clinical evidence of an associated intrahepatic cholangiocarcinoma. After the operation they underwent matured T-tube tract ductal dilatation with percutaneous transhepatic cholangioscopy tube stenting. Choledochoscopic electrohydraulic lithotripsy was used in five patients after dilatation when impacted or large stones were encountered.

RESULTS

Complete clearance of the stones was achieved in these 13 patients. One patient had fevers develop after ductal dilatation, and another patient had mild hemobilia after electrohydraulic lithotripsy. Both recovered uneventfully with conservative treatment. These successfully treated patients remain well, with a mean follow-up period of 20 months.

CONCLUSIONS

Postoperative matured T-tube tract ductal dilatation and stenting, combined with endoscopic electrohydraulic lithotripsy when indicated, is an effective and safe alternative to hepatic resection for selected left hepatolithiasis with intrahepatic biliary stricture.

Postoperative T-tube cholangiography: is routine antibiotic prophylaxis necessary? A prospective, controlled study

OBJECTIVE

To determine the value of antibiotic prophylaxis for the prevention of infection following postoperative T-tube cholangiography.

DESIGN

A prospective, controlled study.

SETTING

A tertiary care center.

STUDY PARTICIPANTS

The role of antibiotic prophylaxis during postoperative T-tube cholangiography was prospectively evaluated in 164 patients.

INTERVENTION

Sixty-two patients were administered antibiotic prophylaxis treatment (1 g of cephalothin sodium was infused intravenously 30 minutes before the procedure and 500 mg of cephalexin was given orally every 6 hours for 3 days after the procedure). Seventy-one patients were in the control group and did not receive antibiotic therapy.

MAIN OUTCOME MEASURES

Complications and adverse reactions following postoperative T-tube cholangiography were recorded and compared between the two groups.

RESULTS

There was no significant difference between the groups in regard to age, sex, serum amylase level before T-tube cholangiography, white blood cell count, and liver function. The results of the bacteriologic culture specimens of the bile were also comparable between the groups. One patient who had received antibiotic therapy and one patient in the control group had fever (temperature, > 38 degrees C) and chills after the procedure. Two patients who had received antibiotic therapy and one patient in the control group had mild abdominal pain. These complications were treated conservatively without any event. No significant difference was found in the rates of complications and the success of postoperative T-tube cholangiography between the groups.

CONCLUSION

Routine antibiotic prophylaxis for the prevention of infection following postoperative T-tube cholangiography is not necessary under selected conditions.

Mesenteric cystic lymphangioma with myxoid degeneration: unusual CT and MR manifestations

We report an unusual case of mesenteric cystic lymphangioma presenting as a large multilocular mass with a well-enhanced solid component and a central cleft, which were were pathologically correlated to the prominent stromal myxoid degeneration interspersed with abundant capillaries and the central fibrosis, respectively. The findings of computed tomography and magnetic resonance imaging are illustrated. Recognition of the multilocular configuration of the enhanced stroma may help to make the correct preoperative diagnosis.

Prenatal diagnosis by transabdominal chorionic villus sampling in the second and third trimesters

From October 1989 through December 1993, 124 pregnant women (114 in the second trimester and 10 in the third trimester) underwent transabdominal chorionic villus sampling (CVS) for prenatal molecular or cytogenetic diagnosis. The mean gestational age was 18.2 weeks. Indications for CVS comprised single gene disease (72%), fetal anomalies detected by ultrasound (17%), advanced maternal age (6%), and previous siblings with chromosomal aberration (5%). Among the 89 fetuses at risk for single gene disease, 20 were diagnosed as affected by DNA analysis. Among the 35 fetuses at risk for chromosomal anomaly, 4 had trisomy, 3 had a 45,XO karyotype and 2 had a structural chromosomal abnormality. The miscarriage rate was 1.8% (2/114) and the spontaneous preterm birth rate was 2.4% (3/124). No maternal or other fetal complications occurred. This study suggested that second- and third trimester CVS is a safe and useful method for prenatal diagnosis.

Ultrasonographic scanning of placental thickness and the prenatal diagnosis of homozygous alpha-thalassaemia 1 in the second trimester

In order to evaluate the association between placental thickness (PT) and fetal homozygous alpha-thalassaemia 1 before the appearance of classic ultrasound findings of haemoglobin (Hb) Bart's hydrops fetalis, a total of 473 pregnancies were collected. The control group included 422 normal pregnancies with a gestational age from 14 to 23 weeks and the study group included 51 affected fetuses in the same gestational period. Fetal biparietal diameter (BPD) and PT were measured by high-resolution ultrasound. PT was evaluated against BPD. In the control group, the PT generally increased in parallel with the advancement of gestational age. All PT measurements in the study group were above the mean PT of their respective gestational week in the control group. Forty-six (90 per cent) of the pregnancies in the study group had PT larger than the mean plus two standard deviations of the control group. This study suggests that ultrasound measurement of PT may be a useful aid in the prenatal diagnosis of Hb Bart's hydrops fetalis before its classic findings become apparent in the late second trimester or third trimester.

In vivo CD3+CD25+ lymphocyte subpopulation is down-regulated without increased serum-soluble interleukin-2 receptor (sIL-2R) by gonadotropin releasing hormone agonist (GnRH-a)

PROBLEM

To test further whether the suppression of the CD3+CD25+ lymphocyte subpopulation by gonadotropin-releasing hormone agonist (GnRH-a) is related to the change in levels of cytokines and soluble interleukin-2 receptor (sIL-2R).

METHOD

Twenty-seven infertile patients were enrolled under the long protocol of GnRH-a agonist (buserelin acetate) and superovulation with gonadotropin from our IVF-ET program. Peripheral B cells, NK cells, CD4+ and CD8+ T cells and the expression of CD69, CD25, HLA-DR, and CD71 antigens on the T cells were serially examined by dual-color flow cytometry. Serum levels of cytokines and sIL-2R were measured.

RESULTS

The B cells, NK cells, T cells, CD4+, CD8+ T cells, CD3+DR+, and CD3+CD71+ lymphocyte subpopulations were not changed after the use of GnRH-a. The CD25+ T cell subpopulation was significantly down-regulated, but the CD69+ T cell subpopulation was increased when the GnRH-a was used for approximately 2 wk. The serum levels of interleukin-1 beta (IL-1 beta), interleukin-2 (IL-2), interleukin-4 (IL-4), interferon-gamma (IFN-gamma), and sIL-2R were not changed.

CONCLUSION

The GnRH-a had a transiently suppressive effect on CD25+ T cells, but a stimulatory effect on CD69+ T cells. However, the serum level of cytokines or sIL-2R did not change. These immunological modulations seems to be the result of interaction between GnRH-a and estrogen.

Transesophageal indirect atrial pacing for open-heart surgery in children

BACKGROUND

Transesophageal atrial pacing (TAP) has been successfully applied for clinical use for more than 30 years. Not only for cardiac pacing, or diagnosis and treatment of rhythmic disturbance but also for assessing the presence and severity of coronary artery disease and maintaining adequate heart rate can TAP provide satisfactory effect. In this study we applied TAP on children undergoing the cardiac surgery to evaluate its efficacy and side effects during such major surgery.

METHODS

Twenty-four children (15 M and 9 F) undergoing open-heart surgery with informed consents were included in this study. After induction of anesthesia the bipolar pacing electrode (Tapcath, Arzco Medical Electronics) was inserted into esophagus through the nose until the ideal site for atrial pacing was found by monitoring the esophageal ECG lead (lead I), and then initiation of atrial pacing was performed by applying the transesophageal cardiac stimulator (Arzco Medical Electronics). Continuous ECG, arterial blood pressure and central venous pressure (CVP) were simultaneously monitored and recorded. Patient's height, inserted length of the pacing electrode, current and pulse duration for effective atrial pacing were also recorded.

RESULTS

The effective rate for initiating sinus tachycardia (atrial capture) by applying TAP was 79.2% (19/24) in our study. For effective atrial pacing the average current was 11.6 +/- 2.4 mA, the average stimulus pulse duration was 4.8 +/- 1.0 ms, and the average inserted length of bipolar electrode was 19.1 +/- 2.2 cm.

CONCLUSIONS

TAP method can be applied satisfactorily in children undergoing cardiac surgery. If urgent cardiac pacing must be applied in these patients TAP would be a choice.

[Mediastinal mass and anesthesia in children--a case report]

A three-year-old girl with mediastinal mass received right exploratory thoracotomy was reported. The mediastinal mass of this patient occupied the whole right lung and compressed the right main bronchus as confirmed by X-ray and CT of the chest. For mediastinal mass surgery, several fatal hazards can happen during induction of anesthesia, maintenance and even the post-operative period. The two main hazards are trachobronchial obstruction and cardiovascular collapse. We presented our experience of this case including preparation, planning, induction technique, maintenance of anesthesia and postoperative care. We hoped that this can help others to minimize accidents when they handle patients with similar conditions.

Changing epidemiology of human salmonellosis in Hong Kong, 1982-93

A comprehensive analysis of the epidemiology of salmonellosis in a major hospital in Hong Kong from 1982-93 is reported. The trend of salmonella isolations over the past 12 years and changes in the occurrence of individual serotypes are delineated. A total of 5328 isolates were analyzed. Groups B (Salmonella typhimurium and S. derby) and E (S. anatum) were the commonest serogroups isolated from the intestinal tract in all age groups. A significant increase in the isolation of group D salmonellae has been observed since 1989. This is accounted for by a substantial rise in S. enteritidis isolation as seen in Western countries, despite a concomitant decrease of S. typhi. The extraintestinal isolation index (EII) is proposed as an index of the virulence potential of individual serotypes and serogroups. Group D salmonella was found to be the most invasive serogroup. While group D was the predominant serogroup isolated from extraintestinal sites in patients older than 1 year, group B serotypes (especially S. typhimurium) were more frequently seen in infants younger than 12 months.

Recurrent Down's syndrome due to maternal ovarian trisomy 21 mosaicism

A family with three children who had Down's syndrome and one healthy child is reported. Cytogenetic studies of the peripheral blood revealed trisomy 21 in the affected children, and normal karyotypes in both the parents and the healthy child. However, a biopsy of the mother's right ovary showed a mosaic trisomy 21 cell line (8/20 cells). By DNA polymorphism analysis, segregation of trisomy oogonia appeared to be the cause of recurrent trisomy 21.

The interaction of diazepam with vecuronium: a clinical study

BACKGROUND

Diazepam, known to possess myorelaxation property, has been widely used clinically to control muscular rigidity and spasticity. The interactions of diazepam with neuromuscular blocking agents have been extensively studied, yet the results reported are somewhat controversial and inconclusive.

METHODS

The interaction of diazepam with one of the neuromuscular blocking agents, vecuronium, was studied in 20 ASA I-II patients undergoing elective surgery. They were randomly assigned to two groups with ten in each group. Anesthesia was induced with fentanyl, thiopental and vecuronium and maintained with 1% halothane and 70% N2O in O2. The experimental group received diazepam (0.2 mg/kg) 3 minutes prior to vecuronium (0.1 mg/kg) during induction while the control group received vecuronium (0.1 mg/kg) straight without diazepam. Control records of the integrated electromyography showed the response to train-of-four supramaximal stimulation by a Datex Relaxograph during induction. In no time when the first twitch (T1) recovered to 25% of the control, it was topped up again with another intraoperative dose of vecuronium (0.025 mg/kg). From the derived data, the following parameters were calculated and analysed: (1) onset time T10 (the time from the end of injection of vecuronium during induction to depression of T1 to 10% of control twitch height); (2) duration time T25 (the time from administering vecuronium during induction to the time when T1 recovered to 25% of the original twitch height); (3) topup time T25-25 (the time from administering the top dose of vecuronium to the time when T1 returned to 25% of control twitch height again) and (4) recovery time T25-50 (the time of recovery of T1 from 25% to 50% of the control twitch height at the end of the operation).

RESULTS

Significant differences between both groups were found in T10 (221.8 +/- 62.2 vs 135.4 +/- 23.3 sec, p < 0.01) and T25 (41.9 +/- 10.2 vs 50.6 +/- 9.4 min, p < 0.05). The results of T25-25 and T25-50 did not differ much (26.6 +/- 6.9 vs 29.3 +/- 4.4 min, p > 0.05 and 15.0 +/- 8.9 vs 16.9 +/- 8.7 min, p > 0.05 respectively).

CONCLUSIONS

The administration of diazepam (0.2 mg/kg) three minutes prior to vecuronium (0.1 mg/kg) during induction may hasten the onset of vecuronium and prolong its duration of action.

Ultrasound diagnosis of rudimentary uterine horn pregnancy in fourteen weeks of gestation: a case report

Pregnancy in a rudimentary uterine horn is rare. Rupture tends to occur in the second trimester, and results in maternal morbility and mortality. Although the diagnosis prior to rupture is difficult, early detection is essential in avoiding a fatal outcome. An asymptomatic case of pregnancy in the rudimentary horn of a bicornuate uterus prior to rupture is presented. This report is to emphasize the important value of sonography for early detection of the prerupture of the rudimentary pregnancy.

Differentiation of Mycobacterium tuberculosis strains by arbitrarily primed polymerase chain reaction-based DNA fingerprinting

Arbitrarily primed polymerase chain reaction (AP-PCR) method was applied to the differentiation of clinical isolates of M. tuberculosis strains. The primer which is specific to human papilloma virus (HPV) type 18 was found to be appropriate for the AP-PCR-based differentiation of M. tuberculosis isolates, since AP-PCR produced multiple polymorphic DNA bands when M. tuberculosis DNA was used as template. AP-PCR was performed using either one of the HPV type 18 primer and IS6110-specific primer (half-specific PCR, HS-PCR) or HPV type 18 primer pair only (nonspecific PCR, NS-PCR). The usefulness of these two methods in differentiating M. tuberculosis isolates, was measured by calculating dissimilarity values of 16 isolates using Cluster Analysis software. The highest dissimilarity values by HS-PCR and NS-PCR methods were 0.38 and 0.59, respectively. This suggested that NS-PCR method is better than HS-PCR method in strain differentiation. Although the dissimilarity value calculated by Cluster analysis of the standard restriction fragment length polymorphism method, in which IS6110 was used as a probe, was much more higher than the NS-PCR method, NS-PCR method using HPV 18 primers was quite useful for the differentiation of M. tuberculosis strains due to its rapidity and simplicity.

Participation of noradrenergic neurotransmission in the suppression by substance P of alpha 2-adrenoceptors at the nucleus reticularis gigantocellularis involved in central cardiovascular regulation in the rat

We applied reverse microdialysis and HPLC analysis to quantify the participation of noradrenergic neurotransmission in the modulation by substance P of alpha 2-adrenoceptors at the nucleus reticularis gigantocellularis involved in cardiovascular regulation, using Sprague-Dawley rats anesthetized with pentobarbital sodium. The efficacy of circulatory suppression of a centrally acting alpha 2-adrenoceptor agonist, guanabenz, was used as the experimental index. Continuous infusion of substance P (600 or 1200 pmol/microliters/min) into the nucleus reticularis gigantocellularis through a stereotaxically positioned microdialysis probe (active exchange length: 500 microns, diameter: 220 microns) for 80 min elicited a reduction in the hypotensive and bradycardiac actions of guanabenz (100 micrograms/kg, i.v.). This implied suppression of alpha 2-adrenoceptor activity correlated positively with the time-course of increase in the estimated extracellular concentration of the undecapeptide and norepinephrine in the nucleus reticularis gigantocellularis. Experimentally elevating the concentration of norepinephrine at this reticular nucleus via microinfusion by reverse microdialysis also decreased the efficacy of the cardiovascular suppression of the aminoguanidine compound. These results suggest that substance P may depress the activity of the alpha 2-adrenoceptors in the nucleus reticularis gigantocellularis that are involved in central cardiovascular regulation via an increase in the extracellular concentration of norepinephrine at this reticular nucleus.

Complete heart block induced by general anesthesia in a patient with suspected conduction system defect: a case report

We report a rare incident of complete heart block occurring after induction of general anesthesia in an apparently fit patient. An external temporary pacemarker was first applied, which was then replaced by isoproterenol infusion, but permanent pacing was required postoperatively. The role of anesthesia as a precipitating factor was discussed. It is suggested that surgical patients suspicious of conduction system defect should be under continuous hemodynamic monitoring with temporary pacing at hand during perioperative period.

Characterization and application of microdialysis probes with an active exchange length compatible with small-size brain nuclei in the rat

We communicated the construction, characterization and application of microdialysis probes with an active exchange length that is suitable for experiments involving small-size nuclei in rat brain. Using substance P (SP) as the test substance, we determined that probes with an active exchange length of 180-200 microns exhibited an in vitro recovery of 14.2 +/- 0.8% and in vivo recovery at the nucleus tractus solitarii (NTS) of 24.9 +/- 1.7% for the undecapeptide, calibrated at an infusion rate of 1 microliter/min. We also demonstrated that microinfusion of SP via these probes into the NTS allowed for a correlation of changes in tissue levels of both SP (exogenous substance) and norepinephrine (endogenous substance) with alterations in baroreceptor reflex responses (physiologic phenomenon).