Shih-Wei Lin

Association of μ‐opioid receptor gene polymorphism (A118G) with variations in morphine consumption for analgesia after total knee arthroplasty

Background:u2002 Morphine consumption after a given surgical procedure can vary considerably. Studies show that single nucleotide polymorphism involving the nucleotide position 118 at exon 1 of the μ‐opioid receptor gene (OPRM1) may play a role in mediating the effects of opioids. This study was performed to correlate the A118G polymorphism at OPRM1 with morphine consumption in patients undergoing total knee arthroplasty.

Obstructive sleep apnea: a stand-alone risk factor for chronic kidney disease

BACKGROUNDnPrevious studies have found an association between obstructive sleep apnea (OSA) and chronic kidney disease (CKD). However, subjects with confounding factors such as diabetes and hypertension were not excluded. The purpose of the present study was to determine whether patients with OSA without meeting criteria for diabetes or hypertension would also show increased likelihood of CKD.nnnMETHODSnWe prospectively enrolled adult patients with a chief complaint of habitual snoring. Overnight polysomnography, fasting blood triglyceride, cholesterol, glucose, insulin, creatinine, albumin and hemoglobin A1c, and first voiding urine albumin and creatinine were examined. Estimated glomerular filtration rate (eGFR), urine albumin-to-creatinine ratio (UACR), homeostatic model assessment-insulin resistance and percentage of CKD were calculated.nnnRESULTSnThe final analyses involved 40 patients who were middle-aged [44.8 (8.6) years] predominantly male (83%), obese [body mass index, 28.2 (5.1) kg/m(2)] and more severe OSA, with an apnea-hypopnea index (AHI) of 51.6 (39.2)/h. The mean eGFR and UACR were 85.4 (18.3) mL/min/1.73m(2) and 13.4 (23.4) mg/g, respectively. The prevalence of CKD in severe OSA subjects is 18%. With stepwise multivariate linear regression analysis, AHI and desaturation index were the only independent predictor of UACR (β = 0.26, P = 0.01, R(2) = 0.17) and eGFR (β = 0.32, P < 0.01, R(2) = 0.32), respectively.nnnCONCLUSIONSnHigh prevalence of CKD is present in severe OSA patients without hypertension or diabetes. Significantly positive correlations were found between severity of OSA and renal function impairment.

The prevalence of restless legs syndrome in Taiwanese adults

Aim:u2002 Few studies have examined the prevalence of restless legs syndrome (RLS) in Asian populations, with existing data suggesting substantially lower rates of RLS in Asian populations compared with Caucasians. However, varying definitions of RLS as well as problematic methodology make conclusions about RLS prevalence in Asian populations difficult to interpret. The current study therefore examines the prevalence of RLS in Taiwanese adults.

Gene-gun particle with pro-opiomelanocortin cDNA produces analgesia against formalin-induced pain in rats

Endogenous opioid peptides play an essential role in the intrinsic modulation and control of inflammatory pain, and could be therapeutically useful. These opioid peptides are synthesized as parts of larger precursor molecules. One such precursor molecule is pro-opiomelanocortin (POMC). In this study, we developed a gene-gun method for the transfer of POMC cDNA in vivo, and investigated its therapeutic effect on inflammatory pain in a rat model of formalin-induced pain. Human POMC cDNA was cloned into a modified pCMV plasmid and delivered to the skin of rats by gene gun. Three days after gene-gun injection, 1% formalin was injected. Endorphin levels were measured in the serum and skin after the formalin test, and skin histology was used to detect endorphin after green fluorescent protein (GFP; control) or POMC cDNA transfer. There was no significant difference in the results of acute nociceptive tests between the experimental and control groups. There was also no difference in response between the groups to phase 1 of the formalin test. However, rats which received POMC cDNA via gene-gun injection showed a significantly reduced response in phase 2 of the formalin test. Endorphin immunoreactivity in the skin increased approximately three- to four-fold in experimental animals compared with GFP-treated controls at day 3 after injection. The phase 2 response in animals treated with formalin and naloxone did not differ significantly from the control, implying that the analgesic effects of POMC cDNA particle injection in phase 2 of the formalin test are reversed by naloxone. There are two major findings from this study. First, in vivo DNA delivery by gene gun to the skin is feasible. Second, the production of β-endorphin is insufficient to block phasic pain, but is effective against sensitization of the afferent neurons during phase 2 of the formalin test.

Effect of pretreatment with ketorolac on propofol injection pain.

Background:u2002 Pain on injection is still a major problem with propofol. We performed this study to compare different doses of intravenous (i.v.) ketorolac with and without venous occlusion and its effect on the incidence and the severity of the pain after propofol injection.

Diffuse alveolar damage associated mortality in selected acute respiratory distress syndrome patients with open lung biopsy

IntroductionDiffuse alveolar damage (DAD) is the pathological hallmark of acute respiratory distress syndrome (ARDS), however, the presence of DAD in the clinical criteria of ARDS patients by Berlin definition is little known. This study is designed to investigate the role of DAD in ARDS patients who underwent open lung biopsy.MethodsWe retrospectively reviewed all ARDS patients who met the Berlin definition and underwent open lung biopsy from January 1999 to January 2014 in a referred medical center. DAD is characterized by hyaline membrane formation, lung edema, inflammation, hemorrhage and alveolar epithelial cell injury. Clinical data including baseline characteristics, severity of ARDS, clinical and pathological diagnoses, and survival outcomes were analyzed.ResultsA total of 1838 patients with ARDS were identified and open lung biopsies were performed on 101 patients (5.5 %) during the study period. Of these 101 patients, the severity of ARDS on diagnosis was mild of 16.8 %, moderate of 56.5 % and severe of 26.7 %. The hospital mortality rate was not significant difference between the three groups (64.7 % vs 61.4 % vs 55.6 %, p = 0.81). Of the 101 clinical ARDS patients with open lung biopsies, 56.4 % (57/101) patients had DAD according to biopsy results. The proportion of DAD were 76.5 % (13/17) in mild, 56.1 % (32/57) in moderate and 44.4 % (12/27) in severe ARDS and there is no significant difference between the three groups (p = 0.113). Pathological findings of DAD patients had a higher hospital mortality rate than non-DAD patients (71.9 % vs 45.5 %, p = 0.007). Pathological findings of DAD (odds ratio: 3.554, 95 % CI, 1.385–9.12; p = 0.008) and Sequential Organ Failure Assessment score on the biopsy day (odds ratio: 1.424, 95 % CI, 1.187–1.707; p<0.001) were significantly and independently associated with hospital mortality. The baseline demographics and clinical characteristics were not significantly different between DAD and non-DAD patients.ConclusionsThe correlation of pathological findings of DAD and ARDS diagnosed by Berlin definition is modest. A pathological finding of DAD in ARDS patients is associated with hospital mortality and there are no clinical characteristics that could identify DAD patients before open lung biopsy.

Survival Predictors in Acute Respiratory Distress Syndrome With Extracorporeal Membrane Oxygenation

BACKGROUNDnExtracorporeal membrane oxygenation (ECMO) can be used as a salvage therapy, but the effectiveness is controversial. The aim of this study was to investigate the predictors of mortality and the influence of organ dysfunction scores in severe acute respiratory distress syndrome (ARDS) patients treated with ECMO.nnnMETHODSnThe records of adult severe ARDS patients receiving ECMO support from May 2006 to December 2011 at Chang Gung Memorial Hospital were retrospectively analyzed.nnnRESULTSnThe records of 65 patients with severe ARDS who received venovenous ECMO were analyzed. The hospital survival rate was 47.7%. Survivors were younger than nonsurvivors (41.4 ± 15.4 versus 54.1 ± 16.9 years, respectively; p = 0.002) and had shorter duration of mechanical ventilation before ECMO (52.7 ± 51.1 versus 112.1 ± 101.0 hours, respectively; p = 0.01). Before ECMO, Acute Physiology and Chronic Health Evaluation II, Sequential Organ Failure Assessment, and Multiple Organ Dysfunction scores were significantly lower for survivors than for nonsurvivors. Mortality rate increased with rising predictive score. During 7 days of ECMO use, organ dysfunction scores were significantly lower for survivors than nonsurvivors.nnnCONCLUSIONSnSevere ARDS patients who are younger, have shorter duration of mechanical ventilation, and lower organ dysfunction scores before ECMO initiation have more favorable survival outcome. Early application of ECMO, especially if predictive score is below 2, may improve survival. Organ dysfunction scores before and during ECMO support are correlated with survival.

Patients with severe obstructive sleep apnea syndrome and elevated high-sensitivity C-reactive protein need priority treatment.

Objective: To evaluate the clinical factors predicting the significantly elevated high-sensitivity C-reactive protein (hs-CRP) concentrations, defined herein as hs-CRP ≥ 3 mg/L, in adult males with untreated obstructive sleep apnea syndrome (OSAS). Study Design: Cross-sectional study. Setting: Tertiary referral center. Subjects and Methods: Sixty-five consecutive male patients with newly diagnosed OSAS were enrolled to receive complete medical history review, physical examination, in-laboratory overnight polysomnography, and hs-CRP test. The patients had no current or history of cardiovascular disease. The patients had a mean age of 38.2 ± 9.9 years, body mass index (BMI) of 27.4 ± 3.5 kg/m2, and Epworth Sleepiness Scale (ESS) of 11.3 ± 4.6. The serum levels of hs-CRP were assessed using peripheral venous blood samples. Results: Twenty-three percent of the overall patients had significantly elevated serum levels of hs-CRP. The increase of hs-CRP correlated fairly with BMI, apnea-hypopnea index (AHI), tonsil size, and ESS (r = 0.450, 0.398, 0.393, and 0.300, respectively; all P ≤ 0.05) after adjustment for conventional coronary heart disease risk factors. However, only the AHI could predict for significantly elevated hs-CRP after stepwise multiple linear regression (R 2 = 0.251, P < 0.001). Conclusion: Patients in this study with hs-CRP ≥ 3 mg/L were more prevalent in the severe OSAS group. This observation suggests that the severe OSAS patients need to have their cardiovascular statuses evaluated by use of an hs-CRP screening test.

The thermal and mechanical anti-hyperalgesic effects of pre- versus post-intrathecal treatment with lamotrigine in a rat model of inflammatory pain.

UNLABELLEDnIntrathecal (IT) lamotrigine, a sodium channel blocker which suppresses neuronal release of glutamate, has been shown to produce a long-lasting antihyperalgesic effect in the neuropathic pain models. In the present study, we examined the anti-hyperalgesic effects of pre- versus post-treatment of IT lamotrigine in an animal inflammatory pain model, the inflamed knee joint model of the rat. Thermal and mechanical antinociception was assessed in rats using a modified Hargreaves box and von Frey hairs. Induction of tonic persistent inflammatory pain was induced by intra-articular injection (i.a.) of a carrageenan-kaolin mixture (CK) into the right knee-joint. Rats were randomly assigned to the groups receiving IT lamotrigine in distinct doses of 5, 50 or 100 ug either pre- (10 min before CK injection) or post-inflammation induction (4 h or 23 h). We observed that CK injection resulted in a significant thermal and mechanical hyperalgesia throughout a 24-h observation period. Pre-treatment with IT lamotrigine revealed a time and dose-dependent suppression of thermal and mechanical hyperalgesia, whereas the post-treatment with IT lamotrigine only showed an effect for mechanical nociception.nnnCONCLUSIONnIT Lamotrigine is antihyperalgesic at a dose larger than 50 ug in the early phase of inflammatory pain model. It reverses tactile allodynia but not thermal hyperalgesia when given after the inflammation induction.

Dynamic upper airway changes during sleep in patients with obstructive sleep apnea syndrome

Conclusion: The narrowing pattern of the upper airway in obstructive sleep apnea patients may be different in sleep as compared with awake. Three different types of obstruction were observed in these subjects during drug-induced sleep. The different obstruction pattern during drug-induced sleep suggests that different strategies should be selected in upper airway management. Objectives: To identify the sites of narrowing and evaluate dynamic upper airway movement in patients with obstructive sleep apnea syndrome (OSAS) while awake and asleep. Patients and methods: This study included 10 patients treated for OSAS between August 2003 and June 2004. Overnight polysomnography was performed on all patients. Parameters including gender, age, neck circumference, and body mass index were recorded. Ultra-fast MRI during awake and drug-induced sleep was arranged to evaluate the dynamic motion of the upper airway. Results: The narrowing pattern of the upper airway during awake differed from the narrowing pattern during drug-induced sleep in 3 of 10 subjects. Three different types, palatal obstruction, combined upper and lower pharyngeal obstruction, and circumferential obstruction of the upper airway, were observed in these patients during drug-induced sleep.