Prediction of excessive bleeding after coronary artery bypass graft surgery: the influence of timing and heparinase on thromboelastography

OBJECTIVE: To compare the ability of thromboelastography, when done at either 10 or 60 minutes after protamine reversal of heparin, to predict excessive bleeding after coronary artery bypass graft (CABG) surgery and to investigate, with the use of heparinase, whether heparin contamination was responsible for the difference, if any. DESIGN: Prospective study. SETTING: University hospital, single institution. PARTICIPANTS: Patients undergoing elective CABG surgery (n = 40). INTERVENTIONS: Blood samples for thromboelastography and routine coagulation tests were collected before induction of anesthesia and at 10 and 60 minutes after protamine reversal of heparin. Blood loss and blood product use were recorded postoperatively. MEASUREMENTS AND MAIN RESULTS: Of 40 patients undergoing elective CABG surgery, 10 fulfilled the criteria for excessive postoperative bleeding. The sensitivity of thromboelastography to identify patients who bled was better at 60 minutes than at 10 minutes after protamine reversal of heparin (100% v 70%). There was greater specificity (83% v 40% at 10 minutes; 73% v 20% at 60 minutes) and positive predictive value (58% v 28% at 10 minutes; 55% v 29% at 60 minutes) when heparinase was added. At both times, thromboelastography showed only moderate correlation with total blood loss and the use of fresh frozen plasma or platelets or both. Conventional coagulation tests did not predict excessive postoperative bleeding. CONCLUSION: This study suggests that timing and the use of heparinase influence the predictive ability of thromboelastography, but its usefulness as a sole predictor of post-CABG surgery bleeding is limited.     

Ondansetron in the prevention of postoperative nausea and vomiting after laparoscopic cholecystectomy

Background: There is an increased incidence of postoperative nausea and vomiting (PONV) after laparoscopic cholecystectomy. The aim of the study was to evaluate the efficacy of intravenous ondansetron, a 5-HT anatagonist, for prevention from PONV after laparoscopic cholecystectomy. Methods: Sixty-eight patients were entered into the study. Thirty-six patients were randomized to receive a single intravenous dose of 4 mg of ondansetron before extubation. Thirty-two patients received no prophylaxis. There were no differences in terms of sex ratio, age, ASA status, and duration of operation between the two study groups. Patients were interviewed by an independent observer to assess the postoperative pain and nausea using visual analog score. Patients' satisfaction scores to the procedure were measured. Results: There was no complication in the series. Pain scores at 2 and 24 h after operation and analgesics consumption were not different between the two groups. For the patients who received ondansetron, the mean (SD) nausea score at 2 and 24 h was 1.5 (1.2) and 1.4 (1.4), respectively. The score for the control group was 1.4 (1.0) and 1.2 (0.5), respectively. There was also no difference in episodes of vomiting and usage of antiemetics between the two groups. Both groups were equally satisfied with the procedures. Conclusion: Routine use of ondansetron does not reduce the incidence of postoperative nausea and vomiting after laparoscopic cholecystectomy.     

Molecular genetic study of congenital nephrogenic diabetes insipidus and rescue of mutant vasopressin V2 receptor by chemical chaperones

AIM: X-linked nephrogenic diabetes insipidus is a rare disease caused by mutations in the arginine vasopressin V2 receptor (AVPR2) gene, which encodes vasopressin V2 receptor (V2R). More than a half of reported mutations in AVPR2 are missense mutations, and a large number of missense mutant receptors fail to fold properly and therefore are not routed to the cell surface. METHODS: We analysed the AVPR2 gene in 14 unrelated patients with X-linked nephrogenic diabetes insipidus, and found 13 different mutations including eight missense point mutations. The cellular expression patterns of three missense mutant (A98P, L274P and R113W) and wild-type V2R were determined in transfected COS-7 cells. RESULTS: In contrast to wild-type V2R, the cell-surface expressions of mutant receptors were totally (A98P and L274P) or partially (R113W) absent. Instead, they were retained intracellularly. However, treatment of cells with two chemical chaperones (100 mmol/L trimethylamine oxide or 2% dimethyl sulfoxide) or incubation at 26 degrees C restored the cell-surface expressions of mutant receptors. CONCLUSION: These data show that some chemical chaperones correct the mistrafficking of misfolded A98P, L274P and R113W V2R. Thus, we believe that a therapeutic strategy based on chemical chaperones in patients with these mutations is worth trying.     

Improvement of burn pain management through routine pain monitoring and pain management protocol

Introduction

Pain management is an important aspect of burn management. We developed a routine pain monitoring system and pain management protocol for burn patients. The purpose of this study is to evaluate the effectiveness of our new pain management system.

Methods

From May 2011 to November 2011, the prospective study was performed with 107 burn patients. We performed control group (n = 58) data analysis and then developed the pain management protocol and monitoring system. Next, we applied our protocol to patients and performed protocol group (n = 49) data analysis, and compared this to control group data. Data analysis was performed using the Numeric Rating Scale (NRS) of background pain and procedural pain, Clinician-Administered PTSD Scale (CAPS), Hamilton Depression Rating Scale (HDRS), State-Trait Anxiety Inventory Scale (STAIS), and Holmes and Rahe Stress Scale (HRSS).

Results

The NRS of background pain for the protocol group was significantly decreased compared to the control group (2.8 ± 2.0 versus 3.9 ± 1.9), and the NRS of procedural pain of the protocol group was significantly decreased compared to the control group (4.8 ± 2.8 versus 3.7 ± 2.5). CAPS and HDRS were decreased in the protocol group, but did not have statistical significance. STAIS and HRSS were decreased in the protocol group, but only the STAIS had statistical significance.

Conclusion

Our new pain management system was effective in burn pain management. However, adequate pain management can only be accomplished by a continuous and thorough effort. Therefore, pain control protocol and pain monitoring systems need to be under constant revision and improvement using creative ideas and approaches.     

Bioassays of Bacillus sphaericus (strain 1593) against mosquitoes of public health importance in Malaysia

The pathogenicity of Bacillus sphaericus strain 1593 was tested against laboratory-reared larvae of four local species of mosquitoes of public health importance in Malaysia; Aedes aegypti, Anopheles balabacensis, Mansonia uniformis and Culex quinquefasciatus. The bacteria was shake-cultured at 28 +/- 1 degrees C for three days, using Glucose-Yeast Extract Salts medium. After which, the spores and vegetative cells were harvested and stored at 4 degrees C before use. Conditions for bioassays were mean temperature of 25 +/- 1 degrees C and relative humidity 65 +/- 5.0. Twenty third-instar larvae of each species were assayed in 90 ml of diluted spore solution. Each concentration and a control were replicated three times for each bioassay. Larval mortalities at 24 hours and 48 hours were taken and analyzed through Probit Analysis using a computer (IBM 370). LC50 values after 48 hours of exposure showed an increasing order of larval susceptibility as follows: Ae. aegypti (417.70 x 10(4)), An. balabacensis (45.84 x 10(4)), Ma. uniformis (18.23 x 10(4)) and Cx. quinquefasciatus (4.14 x 10(4) spores/ml). With the ability to kill 90% of the Cx. quinquefasciatus larvae tested with just a concentration of 10(5) spores/ml, B. sphaericus (strain 1593) has shown good potential as a biocontrol agent for this species of mosquito.