Combined laparoscopic cholecystectomy and drainage of pancreatic pseudocyst: a case report and review of current management.

Pancreatic pseudocyst is a well recognized complication of acute or chronic pancreatitis. Active treatment (surgical or endoscopic) has been recommended if the pseudocyst persists for more than 6 weeks after the diagnosis. Open trans-abdominal drainage was initially the mainstay treatment for it. However, over the past decade, laparoscopic techniques have been developed to provide patient with minimal access alternative. We report a case of a large symptomatic pseudocyst which developed following attack of severe gallstone pancreatitis. Laparoscopic cholecystectomy and cysto-gastrostomy were done at the same sitting. The operative technique is briefly explained.

Recovery following tonsillectomy a comparison between tramadol and morphine for analgesia.

BACKGROUND: The optimal method of intraoperative analgesia for adult tonsillectomy is uncertain. It is important that recovery should be rapid so that the airway is not compromised. Tramadol hydrochloride is an analgesic with mixed -mu and non-opioid activities which has less respiratory depression effects compared to morphine. PATIENTS AND METHODS: We compared the recovery characteristics of patients undergoing tonsillectomy after they were given either morphine or tramadol for intra-operative analgesia. Seventy-nine ASA (American Society of Anesthesiologists) I patients were randomised to receive either tramadol 1.5 mg/kg (n = 44) or morphine 0.1 mg/kg (n = 35). A standard propofol-desflurane based general anaesthetic technique was used. RESULTS: Patients given tramadol recovered faster compared to morphine as demonstrated by the earlier eye opening at reversal (mean +/- SD, 4.7 +/- 1.5 min versus 5.6 +/- 1.8 min, p = 0.04). There was also significantly less nausea and vomiting in the patients given tramadol as compared to those given morphine (6.8% versus 28.6%, p = 0.01). There were no other clinically important adverse effects in either group. CONCLUSION: We conclude that tramadol given for intra-operative analgesia during tonsillectomy results in faster recovery with significantly less nausea and vomiting in the early postoperative period.

Tracheal intubation by novice staff: the direct vision laryngoscope or the lighted stylet (Trachlight)?

OBJECTIVE: To compare the ease of use of the direct vision laryngoscope and the lighted stylet (Trachlight) by novice staff. METHODS: Ten novice medical officers (MOs) performed orotracheal intubations using either the conventional direct vision laryngoscope (DL) or a lighted stylet device (Trachlight). They performed their DL intubations during the first phase of the study, followed by the Trachlight intubations in the subsequent phase. RESULTS: 51 of 54 (94%) of the DL intubation attempts were successful compared with 36 of 54 (67%) of the Trachlight intubations (p<0.001). The mean (SEM) time for intubation was 44 (7) seconds in the DL group and 66 (13) seconds in the Trachlight group (p=0.004). In addition 45 of 54 (83%) of the DL intubations were successful at the first attempt versus 15 of 54 (28%) in the Trachlight group (p<0.001). CONCLUSION: The results show that the use of the conventional direct vision laryngoscope in novices is associated with significantly shorter mean intubation times and higher success rates on the first attempt compared with the Trachlight.

Patient-controlled sedation with propofol for colonoscopy.

BACKGROUND: Patient-controlled sedation (PCS) allows the patient to titrate the dosage of sedative drugs according to need. METHODS: To compare the efficacy of PCS by using propofol with anesthetist-administered midazolam during colonoscopy, 88 patients were randomized to receive either intravenous midazolam 0.05 mg/kg bolus (1 mg increments as required) or propofol PCS (0.3 mg/kg bolus, zero lockout). Heart and respiratory rates, blood pressure, and oxygen saturation were monitored. Patient cooperation, endoscopist satisfaction, and level of sedation were scored. Patient satisfaction was assessed by questionnaire. To correct for multiple testing of data, statistical significance was asserted only for individually stated p values with p < 0.01. RESULTS: Oxygen saturation and hemodynamics were stable in both groups. Better patient cooperation (good vs. minimal; p = 0.008) and higher endoscopist satisfaction (very good vs. good; p = 0.001) were achieved with PCS. Although more sedated intraoperatively (sedation score 4 vs. 2; p = 0.03 for a single test of hypothesis; correction for multiple testing of data removes this significance), patients in the propofol PCS group were more alert by 30 minutes and discharged earlier (mean and SD times were 43.3 [12.1] min compared with 61.0 [29.7] min; p = 0.001.) More patients in the PCS group (86 vs. 6l%; p < 0.001) were satisfied with their overall level of comfort. CONCLUSION: PCS with propofol is effective and results in high patient satisfaction and faster discharge.

Clinical evaluation of the Mapleson theoretical ideal fresh gas flow sequence at the start of low-flow anaesthesia with isoflurane, sevoflurane and desflurane.

Mapleson used a computer spreadsheet model to predict the theoretical ideal fresh gas flow sequence at the start of low-flow anaesthesia. The aim was to increase the end-expired partial pressure of inhalational agent (PE'an) to one minimum alveolar concentration (MAC) as quickly as practicable and then to keep it constant. Ninety adult patients undergoing elective tonsillectomy under general anaesthesia were randomly allocated to one of three groups (n = 30) to receive isoflurane, sevoflurane or desflurane in oxygen. Fresh gas flow and vaporiser settings as specified by Mapleson were followed in all cases except that the maximum setting for desflurane was 18% (2.7 MAC instead of 3 MAC). Recordings of PE'an were made at 1, 2, 3, 4, 5, 7, 10, 15 and 20 min. Mean values of PE'an exceeded 1 MAC by 2 min in all three groups and remained above this value throughout. Each group's PE'an measurements were divided by their respective 1-MAC value. A simple two-level model (with patients at level 2 and time at level 1), with measurements at 1 min excluded, showed that the fitted value at 2 min and the time-weighted mean for 2-20 min for PE'iso (1.042 [95% CI 0.980-1.104] and 1.044 [0.984-1.104], respectively) were not significantly different from its 1-MAC value, whereas those of the PE'sevo (1.169 [1.119-1.219] and 1.143 [1.119-1.219]) and PE'des (1.305 [1.261-1.349] and 1.140 [1.098-1.182]) were significantly higher than their respective 1-MAC values. The Mapleson concept of an initial high fresh gas flow and high vaporiser settings, followed first by reduced high fresh gas flow, as followed in this clinical study, results in PE'an values close to or slightly higher than predicted in the spreadsheet model.

Intravenous opioids reduce airway irritation during induction of anaesthesia with desflurane in adults.

Desflurane is not used for the induction of anaesthesia despite its favourable pharmacokinetic characteristics because it causes airway irritation. We investigated whether pretreatment with i.v. narcotics reduced unwanted effects. One hundred and eighty adults were randomized to three groups (60 per group) to receive i.v. saline, fentanyl 1 microgram kg-1 and morphine 0.1 mg kg-1, respectively, before inhalational induction with desflurane in nitrous oxide and oxygen. Mean time to loss of response to commands was 4.0 min, without significant differences between groups. The incidence of coughing was greater (25%) in the control group than in the fentanyl (5.0%) and morphine groups (8.3%). The incidence of apnoea was 20.0% in the control group versus 13.3 and 5.0% in the fentanyl and morphine groups, respectively. Laryngospasm developed in 11.7% of controls compared with 3.3 and 1.7% in the fentanyl and morphine groups, respectively. More patients in the control group had excitatory movements (46.7%) than in the fentanyl (16.7%) and morphine (8.3%) groups. These results demonstrate that i.v. opioids reduce airway irritability significantly during inhalational induction with desflurane in adults.

The intubating laryngeal mask airway (ILMA): initial experience in Singapore.

We have evaluated the intubating laryngeal mask airway (ILMA) for ventilation and for blind tracheal intubation. After induction of anaesthesia with fentanyl 1 microgram kg-1 and propofol 3 ml kg-1, the ILMA was placed successfully on the first attempt in all 100 patients. After administration of atracurium 0.5 mg kg-1, blind tracheal intubation was successful in 97% of patients--50% on the first attempt, 42% on the second and 5% on the third. Success was improved by pulling the metal handle of the ILMA towards the intubator in an "extension" manoeuvre, if intubation was not possible on the first attempt. These findings confirm the effectiveness of the ILMA in an Asian population.

Multitude of inverted repeats characterizes a class of anchorage sites of chromatin loops to the nuclear matrix.

In order to understand the nature of DNA sequences that organize chromatin into domains or loops, we have cloned the nuclear matrix DNA (1.7% of the total DNA) from human myelogenous leukemia cells in culture. Nuclear matrix is formed by interactions between specific stretches of DNA of about 0.1 to 5.0 kb with protein transcription factors, nuclear enzymes, and structural proteins. Nuclear matrix is believed to be the exclusive nuclear microenvironment in which initiation of DNA replication, transcription, and repair take place. The matrix attachment regions (MARs) of DNA have transcriptional enhancer activity, harbor the origins of replication of the human genome, and define the borders between neighboring chromatin loops. In this study we report the sequence of the human MAR fragment 19.2 of a size of 542 bp. Hum. MAR 19.2 is composed of TG-, CA-, CT-, and GA-rich blocks and shows 8 perfect and imperfect inverted repeats. Thus, we have identified a novel class of MARs with sequence characteristics divergent from the AT-rich class of MARs. The inverted repeats of the 19.2 sequence might be stabilized into their cruciform configuration by torsional strain and by specific transcription/replication protein factors. This MAR might function in the initiation of replication of the flanking chromatin domain and in the regulation of the transcriptional activity of the gene(s) that reside in this domain.

Comparison of the promoter region of the human and porcine choline acetyltransferase genes: localization of an important enhancer region.

Genomic clones of human and porcine choline acetyltransferase were obtained by screening genomic libraries with synthetic oligonucleotides. The human and porcine genes exhibit significant conservation of both their intron/exon structure and the nucleotide sequence in their 5' flanking regions. However, the two genes differ in several respects, including the absence of a "TATA" box in the human gene and differences in the position of the methionine start codon. Analysis of the promoter region of the two genes has led to the localization of an enhancer element that appears necessary for efficient transcription of the gene.

Characterization and location of divalent cation binding sites in bovine glial fibrillary acidic protein.

In our previous work [Yang, Z. W., & Babitch, J. A. (1988) Biochemistry (preceding paper in this issue)] divalent cations were found to be more effective promoters of astroglial filament formation than were monovalent cations. To determine if one or more divalent cation binding sites were the basis for this difference, glial fibrillary acidic protein (GFAP) was attached to nitrocellulose membranes and bathed in 1 microM 45CaCl2 in 60 mM KCl, 0.5 mM MgCl2, and 10 mM imidazole hydrochloride, pH 7.4. After removal of unbound 45Ca2+, GFAP was observed to bind calcium. Flow dialysis experiments showed that GFAP, dissolved in 2 mM Tris-HCl, pH 7.5, contained three classes of binding sites and 0.61 +/- 0.08 (SD), 1.7 +/- 0.4, and 4.6 +/- 0.2 sites per GFAP molecule with dissociation constants of 0.66 +/- 0.01 microM, 6.6 +/- 0.3 microM, and 44 +/- 1 microM, respectively. After addition of 0.5 mM MgSO4 to the flow dialysis solution, the high- and low-affinity sites were not observed while the remaining sites (1.95 +/- 0.15 per GFAP molecule) had a Kd = 2.16 +/- 0.25 microM. This showed that the high- and low-affinity sites are "Ca2+-Mg2+" sites while sites with intermediate affinity are calcium specific. To locate the calcium-binding regions, GFAP peptides were examined for calcium binding by calcium-45 autoradiography. The calcium-specific binding areas were localized in coil I. Computer-assisted analysis of the GFAP sequence revealed several EF-hand-like areas which could be the calcium binding sites. We conclude that divalent cations may play both structural and regulatory roles in astroglial intermediate filaments.