Wide Local Excision and Radiotherapy for the Treatment of Ductal Carcinoma in situ of the Breast: the Hong Kong Experience

AIMS

Breast conservation treatment for ductal carcinoma in situ (DCIS) was unpopular in the Chinese population and the outcome was seldom reported. We conducted a single-centre retrospective study to examine the clinical outcome of women in Hong Kong.

MATERIALS AND METHODS

Seventy-five Chinese women were treated with wide local excision and radiotherapy for DCIS of the breast between 1994 and 2003. Only 26 (34.7%) women had non-palpable DCIS detected by screening mammograms. All women were treated with whole breast irradiation of 50 Gy in 2 Gy daily fractions, with 50 (66.7%) women receiving an additional electron boost of 10-16 Gy.

RESULTS

The median follow-up was 5.1 years (range 2.0-10.7). At the last assessment, four women developed local recurrences, but all remained disease-free after salvage mastectomy. The 5-year actuarial local failure-free rate and cause-specific survival rate were 92.9% (95% confidence interval 89.4-96.4) and 100.0%, respectively. Cosmetic results were rated as good to excellent in all women. On univariate analysis of prognostic factors for local failure, only a close (< or = 2 mm) final resection margin approached statistical significance (hazard ratio 9.108; 95% confidence interval 0.946-87.655; P = 0.056). The 5-year actuarial local failure-free rates for women with a close (< or = 2 mm) final resection margin and women with wider margins were 77.0 and 98.2%, respectively.

CONCLUSIONS

Despite geographical and demographic differences, the clinical outcome after wide local excision and radiotherapy for DCIS of the breast in Chinese women is comparable with that in Western series. Efforts are needed to achieve cosmetically acceptable tumour-free margins greater than 2 mm.

Phase II trial of temsirolimus (CCI-779) in patients with relapsed or refractory multiple myeloma (MM): Preliminary results

7616

Background: Temsirolimus (TEM) is a novel inhibitor of mTOR, a critical molecule in the PI3K/Akt pathway, which is known to play an important role in transducing mitogenic signals induced by the action of cytokines on MM cells. Methods: We performed a phase II trial to investigate the clinical activity and toxicity of TEM in relapsed/refractory MM patients. Patients had Salmon-Durie stage I-IIIA, failed at least one prior therapy, were ≥18 years, had ANC ≥1.2x109/l, platelets ≥75x109/l, serum Cr ≤1.5 mg/dl, fasting cholesterol ≤350 mg/dl, triglycerides ≤400 mg/dl, and ECOG performance status 0–2. TEM was dosed at 25 mg IV on days 1, 8, 15 and 22 of each 28-day cycle. Treatment was continued until progression. Results: 14 patients are evaluable for response and toxicity. Median age was 62.5 (range, 41–75) years; 8 patients were male. 12 patients had stage IIIA and 1 patient had stage IIA and IA each, respectively. Median β2-mg was 3.3 (range, 2.5–7.9) and CRP was 2.2 (range, 0.5–139). Patients had failed a median of 2 (range, 1–5) prior regimens, and 6 had failed autologous stem cell transplant. Overall, 6 (43%) of 14 patients responded, with 5 achieving minor (26–49% decrease in M-protein) responses, and 1 a partial (>50% decrease in M-protein) response using Bladé criteria. 11 patients progressed on treatment. Overall, median time-to-progression was 4.6 months from start of treatment. Grade 3/4 toxicity included neutropenia (n=2), thrombocytopenia (n=2), interstitial pneumonitis (n=1), nausea (n=1), stomatitis (n=1) and diarrhea (n=1). Response was associated with a maximal reduction in phosphorylated p70S6K (p-p70S6K) and 4EBP1 (p-4EBP1) in peripheral blood mononuclear cells at 48 hours after TEM dosing. The median proportion of p-p70S6K relative to baseline following treatment was 0.38 (range, 0.26–0.84) in responding patients versus 1.65 (range, 0.74–1.66) in non-responders (P=0.0001). Similarly, the median proportion of p-4EBP1 following treatment in responders was 0.49 (range, 0.12–1.25) versus 1.12 (range, 0.73–2.09) in non-responders (P=0.025). Correlation with blood levels of TEM is ongoing. Conclusions: TEM has anti-myeloma activity, and further investigation of TEM as a single agent and in combination therapy is warranted.

No significant financial relationships to disclose.

Preliminary results of concurrent chemotherapy with intensity-modulated radiation therapy (IMRT) for advanced cancer of the larynx/hypopharynx

5544

Purpose: Retrospective review of an institution’s IMRT experience in treating advanced laryngeal/hypopharyngeal carcinoma with concurrent chemotherapy. Methods: Between 1/02–6/05, 31 patients with advanced laryngeal/hypopharyngeal carcinoma (74% T3/T4 disease;71% stage IV) underwent combined modality treatment. There were 20 laryngeal and 11 hypopharyngeal carcinomas. All patients received definitive IMRT with a median RT dose of 70 Gy. Concurrent chemotherapy was also given to all patients [cis-platinum (100mg/m2/cycle) or carboplatin/5-fluorouracil (J Clin Oncol 2004;22:69) every 3 weeks for 2–3 planned cycles; 3 patients received a weekly paclitaxel/carboplatin program]. Prophylactic feeding tubes (PEG) were placed in all patients. Acute toxicity and late xerostomia were scored using the RTOG radiation morbidity scale. The 2-year estimates for local progression-free rate (LPF), regional progression-free rate (RPF), distant metastases-free rate (DMF), and overall survival (OS) were calculated using the Kaplan-Meier method. Results: With a median follow-up of 17 months (range: 7–48), 2-year estimates of LPF, RPF, DMF, and OS rates were 76%, 94%, 96%, 87%, respectively. All patients with local failure of laryngeal carcinoma had persistent disease at the end of treatment. Grade ≥2 mucositis was experienced by 68% of the patients during treatment. Xerostomia continued to decrease over time from the end of RT and only 4 still complained of Grade 2 xerostomia. A greater proportion of patients with hypopharynx than larynx cancer were still PEG-dependent (55% versus 25%) after combined modality treatment at the time of this analysis. One patient developed laryngeal necrosis. Conclusions: These preliminary results show that IMRT, in combination with chemotherapy, achieved encouraging local control rates in patients with advanced laryngeal/hypopharyngeal carcinoma. Xerostomia improved over time. Pharyngoesophageal stricture with PEG dependency remains a problem especially in patients with hypopharyngeal carcinoma. Strategies using the ability of IMRT to limit the dose delivered to the esophagus and inferior constrictor musculature may be useful to further minimize this late complication.

No significant financial relationships to disclose.

A phase I study of GTI-2040 (G), an antisense to ribonucleotide reductase (RNR), in combination with high-dose AraC (HiDAC) in acute myeloid leukemia (AML)

6561

Background: RNR converts ribonucleotides to deoxyribonucleotides for DNA synthesis. AraC is converted into AraC triphosphate (AraCTP) and competes with deoxycytidine for DNA incorporation. We hypothesized that RNR downregulation by G leads to lower deoxycytidine levels, preferential AraCTP incorporation into DNA and increased cytotoxicity. A CTEP-sponsored Phase I dose escalation study of G +HiDAC in relapsed/refractory AML tested this hypothesis. Methods: Cohort I (18–59 yrs) received G (dose level (DL) 1: 3.5 mg/m2/d) by continuous IV infusion (CIVI) on d 1–6 + AraC IV q12 hrs on d 2, 4, 6 (DL1: 2500 mg/m2/dose). Cohort II (≥60 yrs) received G CIVI on d 1–6 +AraC IV on d 2 −6 (DL1: 1500 mg/m2/d). An ELISA-based assay measured plasma and intracellular concentration (IC) of G. Results: To date, cohort I included 9 pts with relapsed and 9 with refractory AML; 9 had intermediate and 9 adverse risk cytogenetics (CyG); 8 received prior HiDAC. Cohort II included 10 pts with relapsed and 6 with refractory AML; 8 pts had intermediate and 8 high risk CyG; 5 pts received prior HiDAC. Toxicities were comparable to HiDAC alone. The younger pts had higher AUC and longer t1/2. Of 16 pts evaluable in cohort I (median time to 1st relapse 6 mos), 6 had complete remission (CR) and 1 incomplete CR (no disease and incomplete blood count recovery). In cohort II, no responses were observed. At 120 hrs of antisense infusion, median G IC in marrow cells was higher (i.e., 175 vs75 nM) in younger than in older pts. A median 50% decrease in RNR protein was noted in 5/9 and 5/10 pts in cohort I and II, respectively. In cohort I, a median 50% decrease and 200% increase in RNR was noted in CR (n=4) and non-responder (NR; n=9) pts, respectively. In cohort II R2 downregulation did not predict response. In cohort I 62% of the ICs was in nucleus and 21.2% in cytoplasm in CR pts (n=3) vs. 20.3% and 53.5% in NR pts(n=5). Conclusions: G/HiDAC is feasible. Robust plasma and IC levels of G and target downregulation are achievable in vivo. Responses (41%) were observed only in the younger cohort, where CR pts had higher G nuclear IC and target downregulation than NR pts. Dose escalation continues in the younger cohort to establish a dose for Phase II trials.

No significant financial relationships to disclose.

A phase II trial of stereotactic radiosurgery boost following surgical resection for solitary brain metastases

1552

Background: At present there is no standard of care for adjuvant therapy following resection of solitary brain metastases. The objective of this study was to determine the local control, survival, patterns of relapse and the incidence of brain injury following a surgery-stereotactic radiosurgery (SRS) combined therapy approach while avoiding upfront whole brain radiation therapy (WBRT). Methods: The eligibility criteria included radiologically proven solitary brain metastases, KPS≥70 and a neurologic function score of 0–2. Following the surgical resection, SRS was delivered to the surgical cavity 4–8 weeks later to a dose of 15–22 Gy in a single fraction using the BrainLAB linear accelerator system. Patients were followed with neurological examination and serial MRI images done every 3 months following the procedure. Results: 25 out of 50 patients needed for the study have been accrued since it opened in August 2004. Four patients have failed locally, with a median time to local failure of 9.5 months. The one year local control at the site of original disease was 35%. Two of the four patients who had local recurrence at the time of relapse also had evidence of leptomeningeal disease. Six additional patients developed new brain metastases, resulting in a 1 year brain relapse free survival of 38% following the combined approach. The median overall survival was 12 months. One patient (4%) developed radiation necrosis that required surgical intervention 6 months following the procedure. Six patients (24%) needed WBRT, two patients (8%) needed further SRS and one patient (4%) needed surgery as salvage following development of new brain lesions with this approach. Conclusions: The preliminary results of surgery-SRS approach appear inferior to surgery-WBRT data for solitary brain metastases in terms of local control and development of new brain metastases. However, relapses can be subsequently managed with WBRT without adversely affecting the overall survival and the morbidity.

No significant financial relationships to disclose.

Clinical utility of genotyping resistance test on determining the mutation patterns in HIV-1 CRF01_AE and subtype B patients receiving antiretroviral therapy in Hong Kong

BACKGROUND

HIV-1 genotypic resistance test (GRT) has been widely used to monitor HIV infection but only few reports revealed the mutation patterns of non-B HIV-1 subtypes.

OBJECTIVE

To evaluate the concordance of GRT and clinical treatment outcomes on different HIV-1 subtypes and monitor the mutation patterns and frequencies.

STUDY DESIGN

Pre- and post-treatment plasma samples from 123 patients (39 treatment naïve and 84 treatment experienced) were tested by ViroSeq HIV-1 Genotyping System followed by analysis using the Stanford HIV database. The mutation patterns and frequencies developed in the pol gene were compared among subtypes.

RESULTS

HIV-1 subtypes among patients in Hong Kong were mainly subtype B and CRF01_AE. Primary mutation was not detected among all pre-treatment samples. For post-treatment samples, primary mutations were only detected in the treatment failure group. The mutation patterns and frequencies were similar between CRF01_AE and subtype B viruses. However, the frequencies of L74V/I and K103N in the reverse transcriptase region were different between CRF01_AE and subtype B viruses. VirtualPhenotype was unable to analyze an in-frame insertion of arginine and isoleucine at protease codon 35 of one CRF01_AE isolate.

CONCLUSIONS

This is the first report to demonstrate the high degree of concordance of longitudinal genotyping data and clinical treatment outcome in patients harboring different HIV-1 subtypes. Our findings shed light to the emergence of resistance mutations and its testing in CRF01_AE, which is relevant to other prevailing places in Asia.

What are the barriers faced by general practitioners in treating depression and anxiety in Hong Kong?

Barriers faced by general practitioners in Hong Kong to manage patients with depression and anxiety disorders and their association with postgraduate qualification in family medicine were studied. Postal questionnaires were sent to 179 family medicine tutors affiliated with a university in Hong Kong with a response rate of 64.2%. 'Too time consuming' was the largest barrier for these physicians in treating patients with depression and anxiety. General practitioners without higher qualifications in family medicine were significantly more likely to report 'lack of confidence', 'lack of experience' and 'lack of supporting service' as being the barriers in treating patients with depression and anxiety. Our results showed that time constraint is an important barrier for general practitioners in managing patients with depression and anxiety in Hong Kong. Having a higher qualification in family medicine may reduce the barriers of having lack of confidence and experience in these physicians.

The effects of a Chinese medicinal suppository (Vitalliver) on insulin-like growth factor 1 and homocysteine in patients with hepatitis B infection

The liver is the major organ for the metabolism of homocysteine (Hcy) and production of insulin-like growth factor 1 (IGF-1). Hcy metabolism and IGF-1 synthesis may be impaired in chronic liver diseases. The study investigated the regulatory effect of a Chinese herbal suppository, Vitalliver, on Hcy and IGF-1, as well as their relationship in patients with hepatitis B infection. Forty patients with chronic hepatitis B virus (HBV) infection without cirrhosis, 25 males and 15 females, were observed for changes in Hcy and IGF-1 after the administration of Vitalliver (one nightly) for a period of 3 months. Serum levels of Hcy, IGF-1 and IGFBP-3 were measured at baseline, and at 1 month and 3 months after treatment. Vitalliver reduced Hcy levels significantly (p = 0.001) from 9.7 +/- 2.8 to 9.0 +/- 2.1 micromol/L after treatment of 3 months. Furthermore, the IGF-1 levels increased significantly (p < 0.001) from 170.2 +/- 81.8 to 212.8 +/- 80.9 ng/mL at 1 month and 187.5 +/- 72.3 ng/mL at 3 months (p = 0.001) after treatment. In conclusion, it is speculated Vitalliver may have a self-regulatory effect on the release of IGF-1 in HBV patients without liver cirrhosis.

A case of tetramine poisoning: a lethal rodenticide

We report a fatal case of suicide presenting with convulsions and subsequently multi-organ failure. Rodenticide poisoning was not suspected until the next day when tetramine was detected in the patient's blood, urine, and food residues. Tetramine is a potent rodenticide with a rapid action and high mortality. The poison has been banned worldwide but is still readily available in Mainland China. Outbreaks of poisoning are reported frequently and doctors should be alert for this lethal toxin.

Does pulmonary rehabilitation give additional benefit over tiotropium therapy in primary care management of chronic obstructive pulmonary disease? Randomized controlled clinical trial in Hong Kong Chinese

OBJECTIVE

To evaluate whether multidisciplinary pulmonary rehabilitation programme (PRP) provides additional benefit over tiotropium therapy in managing chronic obstructive pulmonary disease (COPD) in primary care.

DESIGN

A randomized controlled trial to analyse the difference in outcomes of COPD patients receiving tiotropium plus PRP vs. tiotropium treatment alone.

SETTING

Two primary care teaching clinics affiliated with a university which serves a population of 600,000.

PARTICIPANTS

Fifty primary care COPD patients.

METHODS

Fifty subjects underwent spirometry and their status of COPD was confirmed by using the Vitalograph Gold Standard. They were then assessed by the 6-min walking distance (6MWD), Peak Visual Analogue Scale (Peak VAS) and Chronic Respiratory Disease Questionnaire (CRQ). All subjects were given tiotropium to optimize their treatment. After a 6-week period, half were randomized to the intervention group (i.e. receiving PRP), whereas the rest were randomized to control group which received only medication. Spirometry, 6MWD, Peak VAS and CRQ were performed in both groups at 6 weeks, 12 weeks and 3 months.

OUTCOMES

Spirometry, 6MWD, Peak VAS and CRQ.

RESULTS

Significant improvement (P < 0.05) was seen in 6MWD, symptoms of dyspnoea measured by Peak VAS and CRQ. The improvement was sustained at 3-month follow-up. However, no additional significant improvement was seen in the intervention group when compared with control.

CONCLUSION

Tiotropium therapy has improved health outcomes in COPD patients in primary care settings. A 6 weekly PRP did not give any additional benefits in patients already given tiotropium.

Quality of life, depression and fatigue among persons co-infected with HIV and hepatitis C: outcomes from a population-based cohort

The objective of the study was to describe the additional burden generated by hepatitis C (HCV) infection among HIV-infected individuals as measured by self-reported quality of life, depression and fatigue. The provincial HIV/AIDS Drug Treatment Program (DTP) distributes all antiretroviral medication in the province of British Columbia. Eligibility for accessing antiretrovirals is based on published guidelines commensurate with the International AIDS Society. Each participant is asked to complete a self-administered mailed questionnaire that includes patient sociodemographic information, quality of life measures (Medical Outcomes Study-Short Form (MOS-SF), mental health issues (Centre for Epidemiological Studies Depression scale (CESD) and fatigue information. HIV-HCV co-infected individuals were compared to HIV mono-infected individuals using parametric and nonparametric methods. Multivariate logistic regression was used to examine the impact of hepatitis C on quality of life, depression and fatigue, after controlling for sociodemographics and HIV-specific clinical characteristics. Of the 4,134 individuals who were sent a HIV/AIDS DTP survey in 1999, 2000 or 2001, 484 participants both returned one and had an HCV-antibody test result on file. Of the 484 participants eligible for this analysis, 105 (22%) were HCV-positive. In comparison to the 379 (78%) patients testing negative for HCV, a larger proportion of co-infected patients were female (18% versus 3%, p<0.001), aboriginal (20% versus 3%, p<0.001), had ever injected drugs (79% versus 5%, p<0.001), were unemployed (91% versus 49%, p<0.001) and lived in unstable housing (19% versus 1%, p<0.001) at the time they completed the survey. Co-infected patients reported more symptoms consistent with depression, increased fatigue and poorer quality of life. However, using multivariate modeling, it was determined that the impact of HCV on quality of life, depression and fatigue was better explained by the sociodemographic factors related to poverty and injection drug use, than by HCV itself. In conclusion, individuals co-infected with HIV and HCV represent a patient population with significant physical and mental health challenges. Although these patients experience poorer quality of life, increased depression and fatigue, this experience appears to be primarily related to socio-economic issues rather than HCV infection.

Reducing discriminatory attitudes toward people living with HIV/AIDS (PLWHA) in Hong Kong: an intervention study using an integrated knowledge-based PLWHA participation and cognitive approach

The present paper describes the development and evaluation of an intervention programme aiming to reduce adolescents' discriminatory attitudes toward people living with HIV/AIDS (PLWHA). The intervention programme integrates components of 'virtual interaction' with PLWHA (watching a documentary), knowledge enhancement and a simple cognitive exercise. To evaluate its effectiveness, the programme was implemented to about 600 form 3-4 (grade 9-10) students of three secondary schools in Hong Kong. Using a structured questionnaire, the level of discriminatory attitudes toward PLWHA, knowledge about HIV/AIDS and perceptions about PLWHA, etc. were measured before and after the implementation of the programme. A notable improvement on the level of acceptance of PLWHA and knowledge about HIV/AIDS was found after the implementation of the programme. Negative perceptions about PLWHA also reduced substantially. For instance, before the programme, over one-third (35.7%) of all respondents believed that the majority of PLWHA were promiscuous; the figure dropped to 15.8% after exposure to the programme (adjusted odds ratio = 0.35, p < 0.001). Further, some gender differences were observed. Female respondents tended to be less discriminatory toward PLWHA and responded more favourably to the programme than their male counterparts.

The value of saline salpingosonography as a surrogate test of tubal patency in low-resource settings

BACKGROUND

Tubal factor, which accounts for 15-30% of infertility in all women, is common in developing countries with high rates of pelvic inflammatory disease but limited resources. It is possible to outline the fallopian tubes by injecting isotonic saline transcervically during transvaginal ultrasound scanning of the pelvis, and both color flow Doppler and 3-dimensional scanning modes have been employed to improve visualization of the tubes, with varying success.

METHOD

We investigated the value of saline salpingosonography (SSG), using 2-dimensional transvaginal ultrasound scanning, as a screening test of tubal patency in 113 women by comparing SSG findings to those at HSG or laparoscopy.

RESULTS

The findings at SSG correlated well with the results of HSG or laparoscopy, with an overall concordance of 82.5%. SSG was more accurate at diagnosing patent tubes than blocked tubes and was well tolerated. The results are, however, unreliable when it is difficult to inject the saline and when the patient experiences severe pain during the procedure.

CONCLUSION

SSG is a useful screening tool for investigating infertility, particularly in low-resource settings.

Use of antiretroviral therapy among HIV positive individuals living in British Columbia

The objective of this study was to examine the level of antiretroviral use and characterize individuals accessing antiretroviral therapy in British Columbia. The study was conducted by the British Columbia Persons with AIDS Society and the British Columbia Centre for Excellence in HIV/AIDS. Self-administered questionnaires were mailed out to HIV-positive members from May to September of 2002. Comparisons of sociodemographic characteristics and disease status were made using Pearson's Chi2 and the Kruskal-Wallis test for continuous variables. A total of 764 (51%) HIV-positive participants returned the questionnaire. Of these, 80% reported ever using antiretroviral therapy and 64.5% indicated current use. Reasons for never taking antiretroviral therapy were high CD4 or doctor's advice (74/126; 59%), feeling healthy (50/126; 40%) and being afraid of side-effects (35/126; 28%). Those reporting current antiretroviral use were more likely to be older (p<0.001), white (p=0.01), male (p<0.001), gay or bisexual (p<0.001), graduated from high school (p=0.001), non-injecting drug user (IDU) (p<0.001) and earning a household income greater than CAN$10,000/year (p=0.003). IDU status and length of time since diagnosis remained significantly associated with antiretroviral use in multivariate models. The differences in current antiretroviral use by sociodemographic characteristics such as IDU suggest that the need remains to target marginalized populations in order to maximize the health benefits from antiretroviral therapy.

Neuropathologically distinct prion strains give rise to similar temporal profiles of behavioral deficits

Mouse-adapted scrapie strains have been characterized by vacuolation profiles and incubation times, but the behavioral consequences have not been well studied. Here, we compared behavioral impairments produced by ME7, 79A, 22L, and 22A strains in C57BL/6J mice. We show that early impairments on burrowing, glucose consumption, nesting and open field activity, and late stage motor impairments show a very similar temporal sequence in ME7, 79A, and 22L. The long incubation time of the 22A strain produces much later impairments. However, the strains show clear late stage neuropathological differences. All strains showed clear microglial activation and synaptic loss in the hippocampus, but only ME7 and 79A showed significant CA1 neuronal death. Conversely, 22L and 22A showed significant cerebellar Purkinje neuron loss. All strains showed marked thalamic neuronal loss. These behavioral similarities coupled with clear pathological differences could serve to identify key circuits whose early dysfunction underlies the neurological effects of different prion strains.

Protective effects of Danshensu from the aqueous extract of Salvia miltiorrhiza (Danshen) against homocysteine-induced endothelial dysfunction

Homocysteine (Hcy) is a by-product of methionine metabolism. An imbalance of Hcy in the body may lead to hyperhomocysteinemia, a condition with elevated Hcy concentration in blood that may be one of the risk factors responsible for the development of several vascular diseases (thromboembolism, atherosclerosis, stroke, vascular diseases and dementia). Radix Salvia miltiorrhiza (Danshen), a well-known Chinese medicinal herb that can activate and improve blood microcirculation, is noticeable for its beneficial effect in treating cardiovascular diseases. The present study is to demonstrate the protective effect of Danshen extract against the homocysteine-induced adverse effect on human umbilical vein endothelial cell (HUVEC). Homocysteine (5 mM) not only decreased the cell viability but also caused the disruption of capillary-like structure formation in vitro. The protective effect of Danshen aqueous extract and its active compounds on endothelial cell function were demonstrated through an in vitro tube formation assay, which mimics the new blood vessel formation. To identify the active components in the aqueous extract of Danshen, the content was characterized by instrumental analysis using high performance liquid chromatography with diode array detector (DAD) and electrospray tandem mass spectrometry (ESI-MS/MS). Interestingly, Danshen extract and its pure compounds showed different effectiveness in protecting HUVEC against Hcy-induced injury according to the following descending order: Danshen aqueous extract, 3-(3,4-dihydroxy-phenyl)-2-hydroxy-propionic acid (Danshensu), protocatechuic acid, catechin and protocatechualdehyde. We believed that such findings might provide evidence in understanding the beneficial effects of Danshen on the cardiovascular system.

Pseudo tamponade soon after cardiac surgery: a report of three cases

OBJECTIVE

To describe a syndrome suggestive of tamponade but secondary to increased intra-thoracic pressure due to undetected dyssynchronous expiratory efforts in mechanically ventilated patients soon after cardiac surgery.

METHODS

A retrospective chart review of three patients immediately after cardiac surgery.

RESULTS

All patients developed the tetrad of decreased blood pressure, increased central venous pressure, decreased cardiac index and decreased urine output soon after cardiac surgery without other obvious reasons. In all patients, tamponade was suspected. In all cases, physical examination found no marked evidence of patient-ventilator dyssynchrony but evidence of abdominal muscle tensing and intermittent expiratory efforts not in synchrony with the ventilator cycle. In all patients, sedation and muscle relaxation led to a decrease in central venous pressure, improved blood pressure and improved cardiac index and urine output with full resolution of the syndrome. All patients were successfully extubated within 24 hours of surgery.

CONCLUSIONS

In some postoperative cardiac surgery patients expiratory efforts which are not in synchrony with mechanical ventilation and not immediately obvious to clinicians or intensive care unit nurses can simulate tamponade. Greater awareness of this syndrome may decrease the chance of diagnostic error.