Siriraj Medical Journal

101-107

Authors: Sirilak Suksompong, M.D., Jariya Lertakayamanee, M.D., FRCA, Patiparn Toomtong, M.D., Soisuda Suthadsahavijit, M.D., Kessara Nantapiromporn, M.D., Vimolluck Sanansilp, M.D.

Objective: To assess knowledge, current practice, and attitude of doctors and nurses towards pain management in Siriraj Hospital. Methods: After IRB approval, a questionnaire was distributed to 300 doctors and 382 nurses working in the Departments of Anesthesiology, Medicine, Obstetrics and Gynaecology, Ophthalmology, Orthopedics, Otolaryngo- logy, Radiology and Surgery. Results: The response rate was 93.3% and 89.8% from doctors and nurses, respectively. Doctors (77.9%) and nurses (68.2%) replied that their aim of pain treatment was to eliminate pain without complications. The most common order for analgesics was “as needed (p.r.n.)” (61.6%). They reasoned that they thought it was appropriate (75.4%), for patient safety (60.7%), and they were trained in that way (43.9%). When the patients who had no prescription for pain asked for analgesics, 87.2% of the nurses would call the doctor to ask for medicine, and 2.9% of them would wait for the presence of doctors on the wards. There were 37.9 % of the doctors and 28.0% of the nurses who were reported to have seen patients with serious side effects (drowsiness, hypoventilation) which were usually from opioids. The common analgesics given by both doctors and nurses were paracetamol, NSAIDs, tramadol, COX-2 inhibitors, morphine and meperidine. A few doctors (5.7%) and nurses (2.9%) still believed that the pain treatment in Siriraj Hospital was inadequate. They suggested that the care could be improved by giving more education on pain medications and the methods to use them safely. This, together with changing their attitude towards the aim of pain treatment would improve patients’ need on the basis of safety. Conclusion: Though our personnel had good attitude towards pain management, their practice seemed inadequate. Consequently, the education of both doctors and nurses should be continued.

116-122

Authors: Raveewan Klintip, M.Sc., Rasda Boonprasert, M.Sc., Teera Kolladarungkri, M.D.

Objective: At present, Cushing’s syndrome (CS) is diagnosed by measuring cortisol levels and the dexamethasone suppression test. However, the false positive results were found in patients who have stress or lack of drug compliance. Several studies reported a relationship between cortisol and dexamethasone concentration in plasma and measurement of both has proved most useful for identifying patients’ diagnoses. Although, many highly sensitive and specific methods have been reported, the method which was suitable for routine analysis was required. In this study, we aimed to develop a cheaper UPLC-PDA method and to fully validate it for determination of dexamethasone in human plasma. Methods: Chromatographic separation was carried out by the ACQUITY UPLC™ BEH Shield RP, 1.7 µm (100 x 2.1 mm.I.D.) with mobile phase consisting of 0.05% Trifluoroacetic acid / Acetonitrile in gradient program. The Photodiode Array (PDA) Detector was set at 240.2 nm. Results: The run time was 6 min, 2.40 min for dexamethasone and 3.67 min for prednisolone (IS). The limit of quantification was 2.0 ng/mL. The standard curves are in the range 2-60 ng/mL with good linearity (r2 > 0.9975). The method was acceptable in terms of selectivity, accuracy, precision, stability and matrix effect. The measured dexamethasone concentrations ranged from 2.0 - 8.2 ng/mL (5.12 - 21.03 nmol/L). Conclusion: A highly rapid, sensitive, accurate and reproducible UPLC-PDA method was developed and fully validated for the determination of dexamethasone in plasma. This method was successfully applied to routine measurement of dexamethasone concentration in plasma of patients after the low-dose dexamethasone suppression test.

128-133

Authors: Weerathep Chattanachotikul, M.D., Supornchai Kongpatttanakul, M.D., Sathit Vannasaeng, M.D., Korbtham Sathirakul, Ph.D., Somruedee Chatsriricharoenkul, M.D.

Objective: The purpose of this study was to ascertain the bioequivalence between a test product (100 mcg levothyroxine sodium tablets; Thyrosit®, SRIPRASIT PHARMA Co., Ltd., Thailand) and the reference product (100 mcg anhydrous thyroxine sodium; Eltroxin®, Glaxo SmithKline). Methods: An open-label, 2-treatment, 2-period, 2-sequence, randomized crossover design without washout period was studied in 16 patients (8 females in group 1, 1 male and 7 females in group 2) who were diagnosed hypothyroidism with euthyroid in steady state. The enrolled subjects were given a tablet of 100 mcg levothyroxine sodium either the test or reference product daily for 57 days of each period. At steady state (Day 57 on period 1 and Day 114 on period 2), blood samples were collected over a 24-h interval and the concentrations of T4 were examined by a Microparticle Enzyme Immunoassay technique. Pharmacokinetic parameters were evaluated from plasma concentration-time profiles of T4 using the non-compartmental analysis without the adjustment of baseline levels. Results: The 90% confidence interval of geometric mean ratio of primary target parameters (Cssmax and AUC0-24(ss)) between the test and reference formulations was entirely within the bioequivalence acceptance limits of 80.00125.00%, which was 103.32% (97.99-108.93%) for Cssmax ratios, and 102.32% (96.97-107.96%) for AUC0-24(ss)) ratios, together with the power more than 80%. In addition, the nonparametric Friedman’s test for Tssmax demonstrated no significant difference between the two formulations (p>0.05). All subjects tolerated their medication well. No serious adverse effect was observed. Conclusion: The test and reference products of thyroxine in this study are bioequivalent and well tolerated.

139-144

Authors: Jongjate Youngsakul, M.D., Vitoon Chinswangwatanakul, M.D., Sirirat Khawsaard, M.PA., Wiroon Boonnuch, M.D.

Background: Post-operative pulmonary complications (PPCs) are common problems after abdominal operations. The incidence varies from 10 to 69% for atelectasis and 9 to 40% for post-operation pneumonia. Many studies have investigated risk factors and risk indices for predicting PPCs. However, no definite predictors for PPCs have yet been described. Objective: To develop a simple, reliable, and safe diagnostic tool for early detection of post-operation pulmonary complications. Methods: A series of 151 consecutive patients scheduled for elective abdominal operations were studied between 1 September 2003 and 31 August 2004 at The Department of Surgery, Faculty of Medicine at Siriraj Hospital. The patients were measured for peak expiratory flow rate (PEFR) a night before operation, followed by every 24 hr post-operation. The data was analyzed using univariate and multivariate regression analyses with respect to post-operation pulmonary complications. Results: A total of 15 patients (9.9%) developed post-operation pulmonary complications. Univariate analysis demonstrated that preoperative PEFR (PrePEFR) and 24 hr post-operation PEFR (PostPEFR) could predict PPCs. Using multivariate regression analyses, the PEFR Score was developed and calculated as (17.24 х Malignant)-(0.16 х PostPEFR). A cut point value was -4.68. The diagnostic sensitivity was 80% and specificity was 73.5%. Conclusion: 24 hours post-operation PEFR is a simple and valuable bedside method for predicting PPCs.

149-154

Authors: Chanatip Metheetrairut, Ph.D., Wichit Suthammarak, M.D., Ph.D.

Limitations in using human samples or performing human experimentation prompt us to seek other organisms to be used as a model in biomedical study. Caenorhabditis elegans (C. elegans) is one of the most powerful model organisms. For the past few decades, many studies in C. elegans have laid a foundation of knowledge regarding numerous biological processes and underlying mechanism of human diseases. In Thailand, however, C. elegans is quite new and not well known in research. This article aims to introduce this small yet tremendously useful invertebrate as a study model for biomedical research to the Thai research community.