Helen Ki Shinn

Genetic polymorphisms in the ABCB1 gene and the effects of fentanyl in Koreans.

P‐glycoprotein (PGP) is a polymorphic transporter encoded by the ABCB1 gene that contributes to the access of xenobiotics into the brain. There is no report on associations between genetic polymorphisms in ABCB1 and the clinical effects of fentanyl, although fentanyl may be a substrate of PGP. One hundred and twenty‐six (126) unrelated Korean patients under spinal anesthesia with intravenous fentanyl (2.5 μg/kg) were recruited. Clinical effects (bispectral index, respiration rate, and need for oxygen supplementation) were monitored and these were compared between genotypes for three single nucleotide polymorphisms in ABCB1 (1236C>T, 2677G>T/A, and 3435C>T). The allele and genotype frequencies were similar to previous data from Asians; the three major haplotypes, TTT (30%), TGC (24%), and CGC (24%) were expected among nine known haplotypes. During the initial 10 min, there were differences in suppression of respiration rate by fentanyl among the three genotypes (P=0.0933 for 1236C>T; P=0.0941 for 2677G>A/T; P=0.0013 for 3435C>T, repeated‐measures analysis of variance), but the differences in bispectral index among genotypes were not observed. Furthermore, patients carrying the linked 3435T and 2677T alleles showed a significant difference in the level of respiratory suppression (P=0.0056); those with genotypes susceptible to fentanyl (1236TT, 2677TT, and 3435TT) showed early (2–3 min) and profound suppression of respiration (65–73% of initial respiration rate) compared with other resistant genotypes (83–85% of initial respiration rate in 1236CC, 2677GG, and 3435CC). Although the need to supply oxygen was not significantly different between genotypes, there was a trend for increased demand by patients carrying both 1236T and 3435T alleles (P=0.0847). In conclusion, our results confirm ABCB1 genotype data for Koreans and suggest that analysis of ABCB1 polymorphisms may have clinical relevance to prevent respiratory suppression by intravenous fentanyl or to anticipate its clinical effects.

A comparison of infraclavicular and supraclavicular approaches to the brachial plexus using neurostimulation

Background A prospective, double blind study was performed to compare the clinical effect of vertical infraclavicular and supraclavicular brachial plexus block using a nerve stimulator for upper limb surgery. Methods One hundred patients receiving upper limb surgery under infraclavicular or supraclavicular brachial plexus block were enrolled in this study. The infraclavicular brachial plexus block was performed using the vertical technique with 30 ml of 0.5% ropivacaine. The supraclavicular brachial plexus block was performed using the plumb bob technique with 30 ml of 0.5% ropivacaine. The block performance-related pain was evaluated. This study observed which nerve type was stimulated, and scored the sensory and motor block. The quality of the block was assessed intra-operatively. The duration of the sensory and motor block as well as the complications were assessed. The patients satisfaction with the anesthetic technique was assessed after surgery. Results There were no significant differences in the block performance-related pain, frequency of the stimulated nerve type, evolution of sensory and motor block quality, or the success of the block. There were no significant differences in the duration of the sensory and motor block. There was a significant difference in the incidence of Horners syndrome. Two patients had a pneumothorax in the supraclavicular approach. There were no significant differences in the patients satisfaction. Conclusions Both infraclavicular and supraclavicular brachial plexus block had similar effects. The infraclavicular approach may be preferred to the supraclavicular approach when considering the complications.

Acid–base alterations during laparoscopic abdominal surgery: a comparison with laparotomy

BACKGROUND Carbon dioxide insufflation during laparoscopic surgery results in an acid-base imbalance. The purpose of this study was to investigate the effect of pneumoperitoneum on the acid-base status using Stewarts approach. METHODS Thirty patients undergoing abdominal surgery were allocated to the laparotomy group (n=15) or the laparoscopy group (n=15). The acid-base parameters were measured 10 min after the induction (T1), 40 min after opening the peritoneum or pneumoperitoneum according to the group (T2), at the end of the surgery (T3), and 1 h after the surgery (T4). RESULTS There were no significant differences in the standard base excess (SBE), strong ion gap, or anion gap between the two groups. In both groups, the SBE decreased at T2, T3, and T4 compared with baseline value. At T3 and T4 in the laparotomy group, the apparent strong ion difference (SIDa) and pH were decreased whereas the lactate and chloride were increased compared with their baseline values. At T2 in the laparoscopy group, the pH was decreased whereas Pa(CO(2)) was increased compared with their baseline values. CONCLUSIONS The decrease in the pH during the pneumoperitoneum was affected by the increase in Pa(CO(2)), which promptly returned to a normal value after the desufflation. On the other hand, the decrease in the pH after laparotomy was affected by the metabolic factors, which persisted an hour after the surgery.

Haemodynamic effects of a milrinone infusion without a bolus in patients undergoing off-pump coronary artery bypass graft surgery

The haemodynamic effects of a continuous infusion of milrinone without an initial bolus dose were evaluated in patients undergoing off‐pump coronary artery bypass graft surgery. After internal mammary artery harvest, milrinone 0.5 μg.min−1.kg−1 (29 patients) or a normal saline infusion (33 patients) was started and continued until all graft anastomoses were completed. Haemodynamic variables were recorded before application of the tissue stabiliser, at 1, 3, 5 and 10 min after the application of the stabiliser, and after its removal. The administration of a milrinone infusion was associated with a smaller decrease in cardiac output and mixed venous oxygen saturation during all the coronary artery anastomoses, with no severe complications and a decreased dose of norepinephrine infused to maintain systemic arterial pressure.

Post-operative nausea and vomiting after gynecologic laparoscopic surgery: comparison between propofol and sevoflurane

Background We compared the incidence and degree of post-operative nausea and vomiting (PONV) in patients who received general anesthesia with propofol or sevoflurane using the Rhodes index of nausea, vomiting, and retching (RINVR) to assess the degree of PONV quantitatively and objectively during the post-anesthetic period. Methods We performed a prospective study involving 38 patients who underwent gynecologic laparoscopic surgery in our hospital between September 2008 and August 2009. Nineteen patients were anesthetized with propofol during the entire anesthetic period and the other 19 patients received 2.0 mg/kg of propofol intravenously, followed by sevoflurane inhalation. Three patients who were anesthetized with sevoflurane were excluded from the analysis because they were omitted during the survey. We studied the patients who had PONV and RINVR scores 1, 6, and 24 hours post-operatively. Results The propofol group had a statistically lower incidence of PONV and lower RINVR scores in the following subclasses within 1 hour of surgery: symptom occurrence; symptom distress; and symptom experience. Conclusions Propofol at induction and during maintenance of anesthesia can be used to prevent PONV within 1 hour post-operatively in patients undergoing gynecologic laparoscopic surgery.

The intermittent sequential compression device on the lower extremities attenuates the decrease in regional cerebral oxygen saturation during sitting position under sevoflurane anesthesia.

Background The sitting position has potential for serious complications such as cerebral ischemia and venous air embolism. This study investigated the effects of intermittent sequential compression device (SCD) on the changes in regional cerebral oxygen saturation (rSO2) during the sitting position. Methods Sixty-six healthy patients undergoing shoulder arthroscopy in sitting position were randomly assigned to either control (N=33) or SCD (N=33) groups. Hemodynamic variables and the rSO2 were measured 5 minutes after the induction of anesthesia (Tsupine, baseline values), and 1, 3, and 5 minutes after raising the patient to a 70-degree sitting position (T1, T3, and T5). The incidence of hypotension was recorded. Results The incidence of hypotension was significantly higher in the control group (8/33) than that in the SCD group (1/33) (P=0.027, odds ratio 0.170, 95% CI 0.042-0.684). The rSO2 was significantly higher in the SCD group compared with those in the control group at T3 and T5. Within the group, rSO2 decreased significantly only in the control group compared with baseline value at T1, T3, and T5. The % change in rSO2 from T0 to T1, T3, and T5 were significantly lower in the SCD group compared to those in the control group. Conclusions The application of SCD to the lower extremities during sitting position under sevoflurane anesthesia was a simple and effective method to attenuate the decrease in cerebral oxygen saturation.

Hypertensive crisis during wide excision of gastrointestinal stromal cell tumor (GIST): Undiagnosed paraganglioma -A case report-

Although paraganglioma (PGL), an extra-adrenal retroperitoneal pheochromocytoma (PHEO), is a rare catecholamine-secreting neuroendocrine tumor, it can cause severe hypertensive crisis during anesthesia or surgery if undiagnosed preoperatively. Extraluminal perigastric masses may be presumed to be gastrointestinal stromal tumors (GISTs) or soft tissue sarcomas even when histologic confirmation is not possible. Therefore, without a histologic diagnosis or symptoms of excessive catecholamine secretion, PGL may be mistaken for GIST. We report a case of preoperatively undiagnosed PGL which caused hypertensive crisis during anesthesia for retroperitoneal mass excision.

Segregation for reduction of regulated medical waste in the operating room: a case report

One-third of all hospital-regulated medical waste (RMW) comes from the operating room (OR), and it considerably consists of disposable packaging and wrapping materials for the sterilization of surgical instruments. This study sought to identify the amount and type of waste produced by ORs in order to reduce the RMW so as to achieve environmentally-friendly waste management in the OR. We performed an initial waste segregation of 4 total knee replacement arthroplasties (TKRAs) and 1 total hip replacement arthroplasty, and later of 1 extra TKRA, 1 laparoscopic anterior resection of the colon, and 1 pelviscopy (with radical vaginal hysterectomy), performed at our OR. The total mass of non-regulated medical waste (non-RMW) and blue wrap amounted to 30.5 kg (24.9%), and that of RMW to 92.1 kg (75.1%). In the course of the study, we noted that the non-RMW included recyclables, such as papers, plastics, cardboards, and various wrapping materials. The study showed that a reduction in RMW generation can be achieved through the systematic segregation of OR waste.

Increased Expression of Herpes Virus-Encoded hsv1-miR-H18 and hsv2-miR-H9-5p in Cancer-Containing Prostate Tissue Compared to That in Benign Prostate Hyperplasia Tissue

Purpose: Previously, we reported the presence of virus-encoded microRNAs (miRNAs) in the urine of prostate cancer (CaP) patients. In this study, we investigated the expression of two herpes virus-encoded miRNAs in prostate tissue. Methods: A total of 175 tissue samples from noncancerous benign prostatic hyperplasia (BPH), 248 tissue samples from patients with CaP and BPH, and 50 samples from noncancerous surrounding tissues from these same patients were analyzed for the expression of two herpes virus-encoded miRNAs by real-time polymerase chain reaction (PCR) and immunocytochemistry using nanoparticles as molecular beacons. Results: Real-time reverse transcription-PCR results revealed significantly higher expression of hsv1-miR-H18 and hsv2-miRH9- 5p in surrounding noncancerous and CaP tissues than that in BPH tissue (each comparison, P<0.001). Of note, these miRNA were expressed equivalently in the CaP tissues and surrounding noncancerous tissues. Moreover, immunocytochemistry clearly demonstrated a significant enrichment of both hsv1-miR-H18 and hsv2-miR-H9 beacon-labeled cells in CaP and surrounding noncancerous tissue compared to that in BPH tissue (each comparison, P<0.05 for hsv1-miR-H18 and hsv2- miR-H9). Conclusions: These results suggest that increased expression of hsv1-miR-H18 and hsv2-miR-H95p might be associated with tumorigenesis in the prostate. Further studies will be required to elucidate the role of these miRNAs with respect to CaP and herpes viral infections.

Refractory Vascular Spasm Associated with Coronary Bypass Grafting

Diffuse refractory vascular spasms associated with coronary bypass artery grafting (CABG) are rare but devastating. A 42-year-old male patient with a past history of stent insertion was referred for the surgical treatment of a recurrent left main coronary artery disease. A hemodynamic derangement developed during graft harvesting, necessitating a hurried initiation of cardiopulmonary bypass (CPB). Although CABG was carried out as planned, the patient could not be weaned from the bypass. An emergency coronary angiography demonstrated a diffuse spasm of both native coronary arteries and grafts. CPB was switched to the femorofemoral extracorporeal membrane oxygenator (ECMO). Although he managed to recover from heart failure, his discharge was delayed due to the ischemic injury of the lower limb secondary to cannulation for ECMO. We reviewed the case and literature, placing emphasis on the predisposing factors and appropriate management.