Effectiveness of participatory ergonomic interventions on musculoskeletal disorders and work ability among young dental professionals: A cluster-randomized controlled trail.

OBJECTIVES: This study is to evaluate the efficacy of participatory ergonomic (PE) intervention on musculoskeletal disorders (MSDs) and work ability among young dental professionals in China. METHODS: A cluster randomized controlled trail was conducted during 2015-2016. Twenty-nine departments from five hospitals in the South of China were randomized into intervention (14 departments) and control (15 departments), with individuals of 125 and 138 dental professionals, respectively. Main participatory ergonomic interventions involved work posture, repetitive motions, tool usage, work break relaxation and work time re-arrangement with total 235 ergonomic changes in the trail. Individual ergonomic risk exposure was assessed by investigator's observation using quick exposure check (QEC). Work ability index (WAI) and MSDs were collected by questionnaires at baseline, and every 3 months during the 1-year follow-up. RESULTS: Follow-up rate was 91% and 96% for the intervention and control group, respectively. Significant reductions in ergonomic risk exposure and MSD prevalence on six anatomic sites were found in the PE group during the different follow-up stages. WAI scores improved by 1.1 (95% CI 0.43, 1.89) after the 9-month intervention. Compared to the control, the PE participants significantly reduced MSDs on neck (OR = 2.93, 95% CI: 1.25, 4.03) and wrists/hands (OR = 2.33, 95% CI: 1.08, 4.21), marginally increased WAI scores by 0.53 (95% CI: -0.02, 1.56) due to the interventions. CONCLUSION: PE intervention is effective in reducing ergonomic risk exposure and MSDs on neck and wrists/hands among young dental professionals. PE ought to be offered in the early dental career for preventing MSDs.

New Regimen of Combining Hepatic Arterial Infusion Chemotherapy and Lipiodol Embolization in Treating Hepatocellular Carcinoma with Main Portal Vein Invasion.

BACKGROUND: The prognosis of HCC patients with main portal vein invasion (Vp4) is poor. We retrospectively reviewed the therapeutic outcomes with our new HAIC regimen in treating Vp4 HCC patients. PATIENTS AND METHODS: Seventy-one patients received the new regimen of combining HAIC (daily infusion of cisplatin (10 mg/m2), mitomycin-C (2 mg/m2) and Leucovorin (15 mg/m2) plus 100 mg/m2 of 5-fluorouracil (5-FU) using an infusion pump for 5 consecutive days) with Lipiodol embolization between 2002 and 2018. Twenty-two patients (31.0%) also received sorafenib. The Kaplan-Meier curve was used to calculate progression-free survival (PFS) and overall survival (OS). The OS of patients with or without additional sorafenib use or extrahepatic spread (EHS) was also compared. RESULTS: Fifty-six patients (78.9%) had Child-Pugh A liver function. The mean maximal tumor size was 10.3 cm. Twenty patients (28.2%) had EHS at their initial diagnosis. The objective response rate according to the Modified Response Evaluation Criteria in Solid Tumors (mRECIST) and median OS were 64.8% and 13 months. The 1-, 2- and 3-year survival rates were 53.1%, 21.5% and 18.7%, respectively. In the subgroup analysis, there were no significant survival difference between patients with HAIC only vs. HAIC plus sorafenib (14 vs. 13 months) and between patients with vs. without EHS (12 vs. 13 months). CONCLUSIONS: Our new HAIC regimen is effective in treating Vp4 HCC patients. Additional sorafenib use with our new HAIC regimen provided no survival benefit.

Portable Interactive Pulse Tactile Recorder and Player System.

Pulse palpation is an effective method for diagnosing arterial diseases. However, most pulse measurement devices use preconfigured pressures to collect pulse signals, and most pulse tactile simulators can only display standard or predefined pulse waveforms. Here, a portable interactive human pulse measurement and reproduction system was developed that allows users to take arbitrary pulses and experience realistic simulated pulse tactile feedback in real time by using their natural pulse-taking behaviors. The system includes a pulse tactile recorder and a pulse tactile player. Pulse palpation forces and vibrations can be recorded and realistically replayed for later tactile exploration and examination. To retain subtle but vital pulse information, empirical mode decomposition was used to decompose pulse waveforms into several intrinsic mode functions. Artificial neural networks were then trained based on intrinsic mode functions to determine the relationship between the driving signals of the pulse tactile player and the resulting vibration waveforms. Experimental results indicate that the average normalized root mean square error and the average R-squared values between the reproduced and original pulses were 0.0654 and 0.958 respectively, which indicate that the system can reproduce high-fidelity pulse tactile vibrations.

Leiomyomatosis peritonealis disseminata mimicking peritoneal carcinomatosis 13 years after laparoscopic uterine myomectomy: A case report.

INTRODUCTION: Leiomyomatosis peritonealis disseminata (LPD) is a rare clinical condition that can be challenging to diagnose because its clinical features mimic other conditions. We present a case of LPD mimicking peritoneal carcinomatosis 13 years after laparoscopic uterine myomectomy using a power morcellator. The aim of this paper is to report a rare case which surgeons can learn from and to provide more clinical information for further studies to investigate LPD. PRESENTATION OF CASE: A 49-year-old woman was referred to us because sonography revealed abnormal abdominal and pelvic nodules. Thirteen years previously, she had undergone laparoscopic uterine myomectomy using a power morcellator. An exploratory laparotomy revealed nodules on the peritoneum, greater omentum, intestinal mesentery, and terminal ileum. We surgically removed all visible nodules and performed bilateral salpingo-oophorectomy. LPD was confirmed based on the morphology and immunohistochemistry results. DISCUSSION: Diagnosing LPD preoperatively may be difficult because its clinical manifestations resemble peritoneal carcinomatosis or metastatic lesions. Abdominal pain due to diffuse tumor growth is a common manifestation. LPD degenerating into malignancy is rare, but possible. The probable etiological factors, clinical manifestations, and treatment options which may aid when dealing with LPD have been described in this report. CONCLUSION: LPD should be considered in women, particularly those with a history of gynecologic surgery presenting with disseminated intraabdominal or pelvic tumors.

Metabolic risk factors are associated with non-hepatitis B non-hepatitis C hepatocellular carcinoma in Taiwan, an endemic area of chronic hepatitis B.

Metabolic risk factors, such as obesity, fatty liver, high lipidemia, and diabetes mellitus are associated with increased risk for nonviral hepatocellular carcinoma (HCC); however, few nonviral HCC studies have stratified patients according to underlying etiologies. From 2005 to 2011, 3,843 patients with HCC were recruited into the Taiwan Liver Cancer Network. Of these patients, 411 (10.69%) who were negative for hepatitis B virus (HBV), surface antigen, HBV DNA, and anti-hepatitis C virus (HCV) antibody were classified as non-HBV non-HCV (NBNC)-HCC. Detailed clinical analyses of these patients were compared with age- and sex-matched patients with HBV-HCC or HCV-HCC for the associated metabolic risk factors. For this comparison, 420 patients with HBV-HCC and 420 patients with HCV-HCC were selected from the 3,843 patients with HCC. Multivariate analyses showed fatty liver (by echography), high triglyceride levels (>160 mg/dL), and diabetes mellitus history to be significantly associated only with NBNC-HCC and not with the matched patients with HBV- or HCV-HCC. When the patients with HCC were further divided into four groups based on history of alcoholism and cirrhotic status, the group without alcoholism and without cirrhosis exhibited the strongest association with the metabolic risk factors. Based on trend analyses, patients with NBNC-HCC with or without alcoholism were significantly different from the matched patients with HBV- or HCV-HCC, except for patients with alcoholism and cirrhosis, in having more than two of the above three risk factors. Conclusion: Metabolic risk factors are significantly associated with nonviral HCC, especially for patients without alcoholism in Taiwan. Because the prevalence of viral HCC is decreasing due to the success of universal vaccination and antiviral therapy, strategies for cancer prevention, prediction, and surveillance for HCC will require modification. (Hepatology Communications 2018;2:747-759).

Comparison of repeated surgical resection and radiofrequency ablation for small recurrent hepatocellular carcinoma after primary resection.

There is controversy concerning whether radiofrequency ablation (RFA) or surgical resection (SR) is a better treatment option for recurrent HCC after resection. In Kaohsiung Veteran General Hospital, from January 2002 to September 2014, a total of 100 consecutive patients who developed recurrent HCCs with a tumor size ≦ 3 cm and tumor numbers ≦ 3 after surgical resection were enrolled. Among these patients, 57 patients received RFA and 43 patients underwent repeated SR. Baseline characteristics at the time of recurrence after hepatic resection and clinical outcomes following treatment of recurrent HCC were compared between the two groups. The baseline data of initial HCC and the first recurrence of HCC were comparable in both groups. The 1-, 3-, 5-year overall survival rates following treatment of the first recurrence of HCC were 97.6%, 82.7%, 56.4% in the repeated SR group and 98.2%, 77.2%, 52.6% in the RFA group (p = 0.69). The 1-, 3-, 5-year disease-free survival rates were 57.0%, 32.1%, 28.6% in the repeated SR group and 60.8%, 26.6%, 16.6% in the RFA group ((p = 0.89). There was a trend whereby patients who underwent repeated SR had more procedure-related morbidity than patients who underwent RFA (16% vs. 7%, p = 0.14). The median total hospital days were longer in the repeated SR group than that in the RFA group (13 vs. 5 days, p < 0.05). In the small recurrent HCCs after SR, RFA achieved similar overall survival and disease-free survival than those with repeated SR as well as having a shorter hospital stay.

Adjuvant hepatic arterial infusion chemotherapy is beneficial for selective patients with Hepatocellular carcinoma undergoing surgical treatment.

BACKGROUND: Recurrence rate after curative surgical resection of Hepatocellular carcinoma (HCC) remains high. Postoperative hepatic arterial infusion chemotherapy (HAIC) has been suggested to improve survival. This study is to investigate the efficacy of HAIC in the patients with poor tumor factors such as vascular invasion or multiplicity. METHODS: From 2006 to 2014, 221 patients with HCC undergoing hepatectomy and pathologically staged as ≧ T2 (American Joint Committee on Cancer TNM staging system, 7th edition) were included. 61 patients received adjuvant HAIC with 5-fluorouracil, cisplatin, and epirubicin. 160 patients received surgery alone. The overall survival time (OST) and disease free survival time (DFST) were compared between the two groups. RESULTS: In all patients, the multivariate analysis of survival data showed that resection margin less than 10 mm was the independent poor prognostic factors. The median OST and DFST between the HAIC and surgery alone groups were 56.4 vs. 56.9 months (p = 0.76), and 50.6 vs. 54.5 months (p = 0.905), respectively. There was no significant difference. For patients with multiple tumors and concomitantly microvascular invasion, the OST was better in the HAIC group (69.7 vs. 54.6 months, p < 0.05). Based on the image and operative finding, we classified multiple HCC's into two types. Type A: multiple small nodules were close to each other or a huge tumor with several satellite nodules. Type B: two or more tumors scattering in separate segments. Our study showed that type A group benefits from adjuvant HAIC much more than type B. (the median OST in type A versus type B were 85.06 vs. 41.53 months, p = 0.0036). CONCLUSION: The surgical outcome for the patients with multiple HCC's and vascular invasion was poor. Our study showed adjuvant HAIC was beneficial in these patients and formed the basis for further randomized controlled trials.

The Hepatitis Viral Status in Patients With Hepatocellular Carcinoma: a Study of 3843 Patients From Taiwan Liver Cancer Network.

Hepatocellular carcinoma (HCC) is the leading cancer death in Taiwan. Chronic viral hepatitis infections have long been considered as the most important risk factors for HCC in Taiwan. The previously published reports were either carried out by individual investigators with small patient numbers or by large endemic studies with limited viral marker data. Through collaboration with 5 medical centers across Taiwan, Taiwan liver cancer network (TLCN) was established in 2005. All participating centers followed a standard protocol to recruit liver cancer patients along with their biosamples and clinical data. In addition, detailed viral marker analysis for hepatitis B virus (HBV) and hepatitis C virus (HCV) were also performed. This study included 3843 HCC patients with available blood samples in TLCN (recruited from November 2005 to April 2011). There were 2153 (56.02%) patients associated with HBV (HBV group); 969 (25.21%) with HCV (HCV group); 310 (8.07%) with both HBV and HCV (HBV+HCV group); and 411 (10.69%) were negative for both HBV and HCV (non-B non-C group). Two hundred two of the 2463 HBV patients (8.20%) were HBsAg(-), but HBV DNA (+). The age, gender, cirrhosis, viral titers, and viral genotypes were all significantly different between the above 4 groups of patients. The median age of the HBV group was the youngest, and the cirrhotic rate was lowest in the non-B non-C group (only 25%). This is the largest detailed viral hepatitis marker study for HCC patients in the English literatures. Our study provided novel data on the interaction of HBV and HCV in the HCC patients and also confirmed that the HCC database of TLCN is highly representative for Taiwan and an important resource for HCC research.

Spectroscopic measurement of absorptive thin films by spectral-domain optical coherence tomography.

A non-invasive method for measuring the refractive index, extinction coefficient and film thickness of absorptive thin films using spectral-domain optical coherent tomography is proposed, analyzed and experimentally demonstrated. Such an optical system employing a normal-incident beam of light exhibits a high spatial resolution. There are no mechanical moving parts involved for the measurement except the transversal scanning module for the measurement at various transversal locations. The method was experimentally demonstrated on two absorptive thin-film samples coated on transparent glass substrates. The refractive index and extinction coefficient spectra from 510 to 580 nm wavelength range and film thickness were simultaneously measured. The results are presented and discussed.

Number of involved lymph nodes is important in the prediction of prognosis for primary duodenal adenocarcinoma.

BACKGROUND: The significance of lymph node involvement regarding the prognosis of primary duodenal adenocarcinoma remains controversial. This study aims to evaluate the prognostic accuracy of nodal metastasis using the seventh edition American Joint Committee on Cancer staging system in patients with primary duodenal adenocarcinoma. METHODS: Between 1993 and 2010, 36 patients who had undergone surgical resection for primary duodenal adenocarcinoma at the Kaohsiung Veterans General Hospital were retrospectively reviewed. RESULTS: The median disease-free survival for all patients was 19 months and the median overall survival was 21 months. Lymph node metastases were found in 26 (72%) of the patients, and 14 patients (39%) patients had in excess of three positive lymph nodes (N2). Patients with N2 disease had significantly reduced overall survival, as compared to patients with three or fewer positive lymph nodes (N1; p = 0.036). In univariate analysis, factors including age >75 years, body weight loss, tumor size ≤ 4 cm, N2 disease and lymph node ratio >0.4 predicted shorter overall survival. Multivariate analysis demonstrated that N2 and lymph node ratio >0.4 are significant risk factors associated with overall survival (p = 0.026 and p = 0.042 respectively). N2 is also the only independent predictive factor for disease-free survival (p = 0.023). CONCLUSION: Subdivision of metastatic lymph nodes into N1 and N2 improves predictive ability. The seventh edition American Joint Committee on Cancer staging system is applicable in the present study with regard to the prediction of the prognosis for primary duodenal adenocarcinoma.

Endoscopic papillary large balloon dilation alone without sphincterotomy for the treatment of large common bile duct stones.

BACKGROUND: Lethal pancreatitis has been reported after treatment for common bile duct stones using small endoscopic papillary balloon dilation. METHODS: We retrospectively evaluated the safety and efficacy of using large balloon dilation alone without the use of sphincterotomy for the treatment of large common bile duct stones in Kaohsiung Veterans General Hospital. Success rate of stone clearance, procedure-related adverse events and incidents, frequency of mechanical lithotripsy use, and recurrent stones were recorded. RESULTS: A total of 247 patients were reviewed in the current study. The mean age of the patients was 71.2 years. Most of them had comorbidities. Mean stone size was 16.4 mm. Among the patients, 132 (53.4%) had an intact gallbladder and 121 (49%) had a juxtapapillary diverticulum. The mean size of dilating balloon used was 13.2 mm. The mean duration of the dilating procedure was 4.7 min. There were 39 (15.8%) patients required the help of mechanical lithotripsy while retrieving the stones. The final success rate of complete retrieval of stones was 92.7%. The rate of pancreatic duct enhancement was 26.7% (66/247). There were 3 (1.2%) adverse events and 6 (2.4%) intra-procedure bleeding incidents. All patients recovered completely after conservative and endoscopic treatment respectively, and no procedure-related mortality was noted. 172 patients had a follow-up duration of more than 6 months and among these, 25 patients had recurrent common bile duct stones. It was significantly correlated to the common bile duct size (p = 0.036) CONCLUSIONS: Endoscopic papillary large balloon dilation alone is simple, safe, and effective in dealing with large common bile duct stones in relatively aged and debilitated patients.

Hepatitis B genotype C correlated with poor surgical outcomes for hepatocellular carcinoma.

BACKGROUND: Genotype B and C are the predominant hepatitis B virus (HBV) strains in Taiwan. We aimed to investigate the role of genotype in HBV-related hepatocellular carcinoma (HCC) after resection. STUDY DESIGN: From October 2005 to November 2008, 64 patients who underwent liver resection for HBV-related HCC were enrolled. HBV genotypes were determined by molecular method. Patient characteristics, biochemical, tumor, and viral factors were evaluated for their prognostic significance. RESULTS: During a mean follow-up of 26.6 ± 13.2 months, patients infected with genotype C had higher HBV viral load (p = 0.007) and worse disease-free survival rate (p = 0.028) than patients with genotype B. By univariate analysis, genotype C, alanine transaminase >50 U/L, tumor size ≥5 cm, and microvascular invasion were associated with tumor recurrence. Further multivariate analysis demonstrated genotype C remained a significant risk factor (p = 0.034). CONCLUSIONS: Genotype C is a strong risk factor for HCC recurrence after resection. More intensive monitoring for recurrence should be considered in patients with genotype C.

Gallbladder cancer manifesting as recurrent common bile duct stone and duodenal ulcer bleeding.

Gallbladder cancer (GBC) is an uncommon disease and is usually asymptomatic. Poor prognosis and high mortality rate have been noted in patients with delayed diagnosis. We report a case of locally advanced GBC with duodenum and colon invasion manifesting as bleeding duodenal ulcer and recurrent common bile duct (CBD) stones. The patient was successfully treated with extended surgery. In patients who have multiple recurrence of CBD stones without common risk factors, concomitant biliary tract malignancy should be included in the differential diagnosis.

Is hepatectomy beneficial in the treatment of multinodular hepatocellular carcinoma?

BACKGROUND/PURPOSE: Hepatectomy remains the standard treatment for primary hepatocellular carcinoma (HCC). However, its role in the treatment of multinodular HCC (MNHCC) is unknown. METHODS: The study consisted of 599 patients undergoing curative hepatic resection for HCC between October 1990 and June 2006, in which 112 patients had MNHCC (tumor number > or = 2). The type of MNHCC was classified into: A, nodules involving one or two adjoining segments; B, large tumor with satellite nodules involving three or more segments; C, three or fewer nodules that are scattered in remote segments; and D, more than three separate tumors. Univariate and multivariate analyses were used to identify the prognostic factors related to postoperative survival. During the same period of time, and from our database of 178 patients with pathologically proven MNHCC who were undergoing nonsurgical multidisciplinary therapy, 48 patients with serum albumin level > or = 3.5 g/dL, total bilirubin < 2 mg/dL, tumor number < or = 3, and tumor size < or = 5 cm were compared with 38 patients with the same condition treated with hepatectomy, in which 16 received one-block resection and 22 underwent multiple-site resection. RESULTS: The overall 1-, 3- and 5-year survival rates for patients with single-tumor HCC and MNHCC were 88.0%, 69.2% and 58.4%, and 86.1%, 55.5% and 29.9%, respectively (p < 0.001). Alpha-fetoprotein > 400 ng/mL, total tumor size > 5 cm, largest tumor size > 5 cm, total tumor number > 3, microvascular invasion, non-A type MNHCC and multiple-site resection were poor prognostic factors for MNHCC in the hepatectomy group. Multivariate analysis revealed that only multiple-site hepatic resection was an independent adverse factor related to postoperative survival. In addition, patients who underwent one-block resection had significantly better survival compared with the nonsurgical group (p = 0.0016), but the multiple-site resection subgroup did not. CONCLUSION: The prognosis of MNHCC is poor in comparison with that of single-nodular HCC. Hepatectomy is the treatment of choice if the tumors can be removed by one-block resection and liver function reserve is acceptable.

Intestinal obstruction in patients with previous laparotomy for non-malignancy.

BACKGROUND: Intestinal obstruction is one of the most common surgical emergencies. The aim of this study was to identify important management information from the evaluation of patients with intestinal obstruction who had undergone previous laparotomy for non-malignancy. METHODS: Data from 176 patients with previous laparotomy for non-malignancy, and who were operated on for intestinal obstruction, were collected and analyzed retrospectively. RESULTS: Gastroduodenal operations, appendectomy, and obstetric/gynecologic procedures were the 3 most common previous abdominal surgeries. More than half of all bowel obstructions developed within 10 years after previous laparotomy, and particularly within the first 5 years. Most obstructions were related to adhesion, although their etiologies were diverse. The rate of bowel strangulation was much higher in patients with internal herniation, volvulus, intussusception, closed loop, and diaphragmatic hernia than in patients with simple adhesion, bezoar, tumor, and inflammation (48.3% vs 12.2%). The surgical mortality rate correlated significantly with bowel strangulation: the overall rate was 6.8%, that in patients with strangulation was 18.8%, and that in patients without strangulation was 4.2%. CONCLUSION: The etiologies of intestinal obstruction were not only significantly related to bowel strangulation, but were also an important determinant of therapeutic strategy.

Multimodality management of hepatocellular carcinoma larger than 10 cm.

BACKGROUND: Hepatic resection for huge hepatocellular carcinoma (HCC) is challenging. The role of multimodality nonsurgical therapy for HCC larger than 10 cm is unclear. STUDY DESIGN: We retrospectively investigated 131 HCC patients with main tumors larger than 10 cm in diameter seen between October 1990 and October 2001. Fifty-six patients (group A) underwent hepatectomy and 75 patients (group B) underwent nonsurgical multidisciplinary therapy including hepatic arterial infusion, transcatheter arterial embolization, and percutaneous acetic acid injection. RESULTS: Patients in group B were older, had lower serum albumin levels, and there were more patients with liver cirrhosis and great vessel invasion. Median survivals of group A and B patients were 17 months and 7 months, respectively (p < 0.001). But the 1-, 3-, 5-year survival rates in group B using 38 patients undergoing 3 or more sessions of nonsurgical treatment were not significantly worse than those for group A using 53 patients with followup (57.1%, 19.0%, 16.3% versus 60.7%, 24.5%, 24.5%, respectively). Group A patients had 37.7% and 71.7% recurrence rates at 6 and 12 months, respectively, after operation, and they had a significantly higher frequency of overall extrahepatic recurrence compared with group B patients (43.4% versus 18.7%, p = 0.005). In group B, only 3 of 35 patients younger than 60 years had tumor shrinkage after nonsurgical treatment modalities in comparison to 17 of 40 patients in the elderly group (p = 0.003). Younger patients had a significantly higher prevalence of hepatitis B surface antigen positivity (85.7% versus 47.5%) and infiltrating tumor growth pattern (74.3% versus 45.0%) compared with older patients. CONCLUSIONS: Our study suggests that the advantage of hepatic resection in patients with huge HCC is marginal. An effective adjuvant therapy is needed to improve outcomes after hepatic resection. The experience in using nonsurgical treatment shows that the result is poor in young patients compared with that in elderly patients.

Use of prophylactic antibiotics in surgery at a medical center in southern Taiwan.

BACKGROUND AND PURPOSE: Use of prophylactic antibiotics to prevent postoperative infection (POI) is a common practice in surgery. This study investigated the amount and cost of surgical prophylaxis in a representative general hospital in Taiwan in order to determine an appropriate course of action to control antibiotic use and decrease the burden of resistance. METHODS: The use of antibiotic prophylaxis for a wide variety of surgical procedures over a 6-month period was retrospectively evaluated in 3,104 patients at a medical center in southern Taiwan. RESULTS: Timing of perioperative parenteral antibiotics was inappropriate in 738 (23.8%) patients. The average duration of antibiotic use was 6.4 days (2.4 days intravenous + 4.0 days oral). Only 4.9% of patients did not receive prophylactic antibiotics and only 9.2% received a single dose. Prophylaxis exceeded 1 day in 80% of patients and 3 days in 68.2%. The most common regimen was cefazolin plus gentamicin, used in 2,338 (75.3%) procedures. There were 146 POIs in 119 (3.8%) patients. The most common POI was at the surgical site. Aerobic gram-negative bacilli were most common among the 81 pathogens isolated (54.3%), followed by gram-positive cocci (34.6%), anaerobes (8.6%) and yeasts (2.4%). The total cost for prophylactic antibiotics was New Taiwan (NT)$5,860,242 (approximately US$ 169,862). Had a single dose of cefazolin been used for all patients, the cost would have been reduced by 92.1%. Had four doses of cefazolin been used, the cost would have been reduced by 68.5%. CONCLUSIONS: This study documented the excessive use and often inappropriate timing of administration of antibiotics for surgical prophylaxis in a representative medical center in Taiwan. Strategies are needed to improve the appropriate use of surgical antibiotic prophylaxis in Taiwan, not only to reduce costs but, more importantly, to delay the emergence of resistant microorganisms.