Biomedical subjects

K K Lam

Publications and source records attributed to K K Lam.

At least 19 recordsLinked to original sources

PubMed2002

Patient-controlled epidural analgesia in a parturient with hypertrophic obstructive cardiomyopathy.

We describe the use of patient-controlled epidural analgesia (PCEA) using fentanyl in the management of a labouring parturient with hypertrophic obstructive cardiomyopathy (HOCM). With non-invasive monitoring, PCEA was started in the early first stage of labour with a bolus dose of fentanyl 20 microg, lockout 5 min and 4-h maximum dose of 500 microg. Analgesia was satisfactory during the early first stage but was poor subsequently, despite a total fentanyl consumption of 760 microg during the 6-h labour. The maternal cardiovascular condition was stable throughout labour and delivery and the baby was born in good condition without subsequent respiratory depression. Opioid-based PCEA is an alternative to systemic analgesia in labouring parturients with HOCM. However, although its use avoids the potential adverse effects of sympathetic block associated with conventional epidural analgesia, our regimen had limited analgesic efficacy in the latter stage of labour.

Journal Article↗

PubMed2001

Cinnamophilin as a novel antiperoxidative cytoprotectant and free radical scavenger.

The antioxidant properties of cinnamophilin were evaluated by studying its ability to react with relevant reactive oxygen species, and its protective effect on cultured cells and biomacromolecules under oxidative stress. Cinnamophilin concentration-dependently suppressed non-enzymatic iron-induced lipid peroxidation in rat brain homogenates with an IC50 value of 8.0+/-0.7 microM and iron ion/ADP/ascorbate-initiated rat liver mitochondrial lipid peroxidation with an IC50 value of 17.7+/-0.2 microM. It also exerted an inhibitory activity on NADPH-dependent microsomal lipid peroxidation with an IC50 value of 3.4+/-0.1 microM without affecting microsomal electron transport of NADPH-cytochrome P-450 reductase. Both 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azo-bis(2-amidinopropane) dihydrochloride-derived peroxyl radical tests demonstrated that cinnamophilin possessed marked free radical scavenging capacity. Cinnamophilin significantly protected cultured rat aortic smooth muscle cells (A7r5) against alloxan/iron ion/H2O2-induced damage resulting in cytoplasmic membranous disturbance and mitochondrial potential decay. By the way, cinnamophilin inhibited copper-catalyzed oxidation of human low-density lipoprotein, as measured by fluorescence intensity and thiobarbituric acid-reactive substance formation in a concentration-dependent manner. On the other hand, it was reactive toward superoxide anions generated by the xanthine/xanthine oxidase system and the aortic segment from aged spontaneously hypertensive rat. Furthermore, cinnamophilin exerted a divergent effect on the respiratory burst of human neutrophil by different stimulators. Our results show that cinnamophilin acts as a novel antioxidant and cytoprotectant against oxidative damage.

Animals↗

PubMed2001

Structured preoperative patient education for patient-controlled analgesia.

STUDY OBJECTIVE: To investigate the effectiveness of a structured preoperative education program in patients receiving patient-controlled analgesia (PCA). DESIGN: Randomized controlled trial. SETTING: University-affiliated hospital. PATIENTS: 60 ASA physical status I and II women undergoing major gynecologic surgery. INTERVENTIONS: Patients were randomly allocated to receive either standard information given during routine preanesthetic assessment (n = 30) or additional structured preoperative education on the use of PCA (n = 30). MEASUREMENTS: All patients received standard anesthesia and PCA was provided for postoperative analgesia. Patients were reviewed bid by an independent team of pain specialists and nurses. Patient satisfaction, severity of postoperative pain, nausea, dizziness, and morphine consumption were measured at discharge from recovery room, 24, and 48 hours after operation. Recovery characteristics of patients were also measured. MAIN RESULTS: Pain scores and morphine consumption decreased over time (p < 0.01), but there was no significant difference between groups. The overall analgesic efficacy, side effects, and recovery times was not affected by the education program. Patient satisfaction in the education group was better than control during early recovery (p= 0.03), but there was no additional benefit in the remaining postoperative period. CONCLUSIONS: Structured preoperative PCA education did not affect patient outcome. The early improvement in patient satisfaction was minimized by continued education and pain team supervision during the rest of the postoperative period.

Adult↗

PubMed2001

Patient-controlled pethidine after major upper abdominal surgery: comparison of the epidural and intravenous routes.

We compared epidural (n = 17) and intravenous (n = 20) patient-controlled analgesia (PCA) using pethidine (bolus 10 mg, lockout interval 10 min, 4-h maximum dose 3 mg.kg(-1)) after total gastrectomy. We found that mean (SD) pethidine consumption in the first 24 h was 33% less in the epidural group [255 (85) mg] than in the intravenous group [379 (129) mg, p = 0.002], although most of this difference occurred in the first 8 h. Plasma concentrations of pethidine were lower at 8 h (p < 0.01) in the epidural group, but were similar at 24 h. Pain scores, side-effects, patient satisfaction and patient outcome were similar between groups. Epidural and intravenous pethidine PCA provided similar efficacy after major abdominal surgery, although the epidural route can reduce the amount of pethidine used initially.

Adolescent↗

PubMed2001

Intubation through intubating laryngeal mask with and without a lightwand: a randomized comparison.

The combined use of a lightwand and the intubating laryngeal mask airway (ILMA) was compared with the use of the ILMA alone to determine whether the combination was a more efficient method of endotracheal intubation. One hundred healthy patients were randomly assigned to two groups. After induction of anaesthesia, Group A patients were intubated blindly through the ILMA while in Group B, intubation was guided by a lightwand. A sequence of standard manoeuvres was followed it attempts at intubation failed. The number of manoeuvres used, the time taken for successful intubation and complications associated with intubation were recorded. Intubations were successful in all patients, but the mean endotracheal intubation time was longer in Group A than in Group B (38.3 +/- 10.4 s versus 26.4 +/- 9.1 s, P < 0.001). The number of patients who needed one or more manoeuvres was significantly higher in Group A than in Group B (76% versus 42%, P = 0.001). We conclude that the lightwand is a useful adjunct in endotracheal intubation through an ILMA.

Adult↗

PubMed2000

An incident of hydrogen cyanide poisoning.

Seven cases of hydrogen cyanide gas poisoning which occurred in an industrial building in Hong Kong are presented here. Two of them were more severely injured and required specific antidotal treatment. The other five were mild and responded to supportive treatment alone. All except one patient recovered completely. Cyanide poisoning is relatively uncommon in urbanized area, so high index of suspicion is important for early diagnosis and treatment. We believe that prevention of cyanide poisoning can be achieved by proper storage of chemicals, and by enforcing rescuers to wear special chemical protective clothing to avoid systemic poisoning because of dermal absorption of hydrogen cyanide gas. As there are newer and safer cyanide antidotes available, each emergency department should have a stock of updated products such as hydroxocobalamin.

Adult↗

PubMed2000

Alfentanil given immediately before the induction of anesthesia for elective cesarean delivery.

Opioids are routinely omitted at the induction of general anesthesia for cesarean delivery because of concerns about neonatal respiratory depression. The subsequent unmodified maternal stress response to tracheal intubation reduces placental perfusion. The short-acting opioid alfentanil may afford advantages at the induction, without subsequent neonatal depression. In this double-blinded study of elective cesarean deliveries, 40 patients were allocated randomly to receive either alfentanil 10 microg/kg (n = 18) or placebo (n = 22), 1 min before the induction of anesthesia with thiopental 4 mg/kg and succinylcholine 1.5 mg/kg. Anesthesia was maintained with 50% nitrous oxide, 0.5% isoflurane in oxygen, and atracurium. Neonates were assessed by using Apgar scores, Neurologic and Adaptive Capacity Scores, and umbilical cord blood gas and catecholamine analysis. After intubation, mothers receiving alfentanil had a smaller increase in mean arterial blood pressure, (11 +/- 15 vs 31 +/- 13 mm Hg, P < 0.001) and lower plasma norepinephrine concentrations, (336 +/- 152 vs 486 +/- 241 pg/mL, P < 0.05). Neonates in the alfentanil group had greater umbilical arterial oxygen tensions (27.8 +/- 7.0 vs 22.6 +/- 7.4 mm Hg), slightly reduced Apgar scores (both P < 0.05), but similar Neurologic and Adaptive Capacity Scores. One neonate in the alfentanil group required naloxone. The maternal stress response was attenuated in the alfentanil group but at the cost of early neonatal depression. However, all neonates should be monitored for possible immediate, but transient, respiratory depression.

Adult↗

PubMed1999

Activation of neurotrophin-3 receptor TrkC induces apoptosis in medulloblastomas.

Elevated expression of the neurotrophin-3 (NT-3) receptor TrkC by childhood medulloblastomas is associated with favorable clinical outcome. Here, we provide evidence that TrkC is more than simply a passive marker of prognosis. We demonstrate that: (a) medulloblastomas undergo apoptosis in vitro when grown in the presence of NT-3; (b) overexpression of TrkC inhibits the growth of intracerebral xenografts of a medulloblastoma cell line in nude mice; and (c) trkC expression by individual tumor cells is highly correlated with apoptosis within primary medulloblastoma biopsy specimens. TrkC-mediated NT-3 signaling promotes apoptosis by activating multiple parallel signaling pathways and by inducing immediate-early gene expression of both c-jun and c-fos. Considered collectively, these results support the conclusion that the biological actions of TrkC activation affect medulloblastoma outcome by inhibiting tumor growth through the promotion of apoptosis.

Animals↗

PubMed1999

Bone marrow examinations as final clue to diagnosis of hypercalcemia: report of two cases.

Two young men with severe hypercalcemia in association with renal failure (one acute and one chronic) are reported in whom usual diagnostic tests failed to reveal an etiology, and the final diagnoses were given by bone marrow examinations. Early bone marrow examinations in specific patients with hypercalcemia of undetermined origin sometimes are vital as shown by our two patients.

Acute Kidney Injury↗

PubMed1999

Low dose desferrioxamine can improve erythropoiesis in iron-overload hemodialysis patients without side effects.

OBJECTIVE: Multiple blood transfusions were often required to treat anemia in uremia patients before the era of recombinant human erythropoietin (r-HuEPO). Iron overload thus frequently occurred in chronic hemodialysis patients. Desferrioxamine (DFO) is an effective chelating agent, which can remove excessive iron and can enhance erythropoiesis. Large dose DFO treatment is a therapy associated with the development of severe complications. In this study, a low dose DFO regime was used to treat iron overloaded hemodialysis patients. The efficacy and side effects of this regiment were evaluated. MATERIALS AND METHODS: Eight iron overloaded chronic hemodialysis patients were enrolled in this study. All patients received DFO 500 mg intravenously twice-a-week for eight months. Serum aluminum, transferrin saturation (TFS) and r-HuEPO requirement were recorded before and after DFO treatment. Serum ferritin and hematocrit (Hct) were measured before, during, and after the DFO withdrawal period. All patients were evaluated and followed closely during treatment. RESULTS: Changes in aluminum, TFS and r-HuEPO dosage were unremarkable (p > 0.05). Hct increased significantly after eight months of DFO treatment (from 25.3% to 27.0%, p < 0.05). Ferritin level was reduced by 43.2% at the end of treatment and an evident decline of ferritin was achieved after four months of treatment (2102 ng/mL to 1166 ng/mL, p < 0.05). All patients tolerated the treatment well and no complications were found. CONCLUSION: Low dose DFO can chelate iron effectively in chronic hemodialysis patients. This treatment can enhance erythropoiesis without adverse effects.

Anemia↗

PubMed1999

Ischemic bowel disease in chronic dialysis patients.

BACKGROUND: Ischemic bowel disease, especially acute mesenteric ischemia, carries high morbidity and mortality rates. Any delay in diagnosis or treatment aggravates the patient's outcome. Owing to the scarcity of reports concerning ischemic bowel disease in chronic dialysis patients, we investigated the ischemic bowel disease in chronic dialysis patients. METHODS: From January 1986 through April 1997, medical records of 2416 chronic dialysis patients at our hospital were reviewed. Among them, 5 patients with surgically documented ischemic bowel disease were enrolled. The clinical manifestations, laboratory findings, operative findings, pathologic test results and prognoses of these patients are reported. RESULTS: Abdominal pain, abdominal distension and bloody stool were major initial presentations. The mean age of the patients was 62.4 years at the time of diagnosis of ischemia. All patients had hypertension, 3 patients had hyperlipidemia, three patients had diabetes mellitus and three patients had history of shunt occlusion. Four patients had leukocytosis. Image studies revealed dilatation of bowel loops in four patients. Peritonitis made exploratory laparotomy necessary. The findings during operation showed turbid ascites and variable degrees of bowel ischemia or gangrene. The methods of surgical intervention depended on the severity of the disease. Only one patient died due to extensive ischemic bowel involvement and subsequent sepsis. CONCLUSION: It is mandatory to have an index suggestive of ischemic bowel disease in chronic dialysis patients with unexplained abdominal pain or discomfort. Early diagnosis and aggressive surgical intervention is the cure modality for patients with acute ischemic bowel disease.

Aged↗

PubMed1999

Spontaneous bacterial peritonitis in adult patients with primary nephrotic syndrome.

BACKGROUND: Susceptibility to bacterial infection is a common problem in nephrotic patients. Spontaneous bacterial peritonitis, although characteristic of nephrotic children, is extremely rare in adults. METHODS: A retrospective review was performed on all adult patients with the discharge diagnoses of primary nephrotic syndrome and spontaneous bacterial peritonitis treated between 1986 and 1998 at Chang Gung Memorial Hospital in Kaohsiung, Taiwan. Ten patients were included in this study, 9 of them men and one woman. The average age was 30.5 years. RESULTS: All the patients had signs of active nephrosis and presented with diffuse abdominal pain, ascites, fever and/or chills. Thirty percent (3/10) of the causative pathogens were gram-positive bacteria and 60% (6/10) were gram-negative bacteria. One patient had sterile cultures. Seven patients recovered after antibiotic treatment for 1 to 2 weeks. Three patients died of septic shock. CONCLUSION: Therefore, to improve patient outcome, it is essential to establish a diagnosis early and to initiate broad-spectrum antimicrobial therapy even before culture results are available.

Adolescent↗

PubMed1998

Successful treatment of acute inferior vena cava and unilateral renal vein thrombosis by local infusion of recombinant tissue plasminogen activator.

Renal vein thrombosis can occur as a complication of nephrotic syndrome. We present the case of a young man with nephrotic syndrome caused by minimal change disease who developed acute inferior vena cava and left renal vein thrombosis. He was treated initially with intravenous heparin. Because of the persistence of severe left flank pain and gross hematuria, local infusion of recombinant tissue plasminogen activator was tried, with resolution of thrombi and subsidence of symptoms. Functional preservation of the involved kidney is good, as indicated by Tc-99m DMSA scan (involved kidney, 47.4%; uninvolved kidney, 52.6%). Anticoagulation is usually recommended as the treatment of choice in renal vein thrombosis. We believe that in cases with critical presentations, such as bilateral involvement, extension into inferior vena cava, acute renal failure, pulmonary embolism or severe flank pain, thrombolytic therapy should be considered as a second-line treatment if good response is not obtained with heparin.

Acute Disease↗

PubMed1998

Pain in Chinese cancer patients under palliative care.

Over a 4-month period, 218 Chinese patients with advanced cancer were admitted to a palliative care unit in Hong Kong. Ninety-five (44%) of them had pain. Of these 95, 70 (mean age 61.7 years) were evaluated with the visual analogue scale (VAS) and the numerical rating scale (NRS). Forty-two per cent of the 70 patients were illiterate. Eighty-three per cent had metastases. Eighty-seven per cent had pain due to the disease process. Forty-nine per cent had more than one pain, 54% had moderate pain and 20% had severe pain. The most common primary tumour was lung cancer. NRS scores strongly correlated with corresponding VAS scores, suggesting that NRS can routinely be used for pain intensity assessment in the Chinese. The study also showed that 64% of these patients with pain had moderate to severe disabilities to the basic activity of daily living, although there was no correlation between the severity of pain and the severity of disability.

Adult↗

PubMed1998

The significance of syphilis serology tests on long-term hemodialysis patients.

BACKGROUND: Syphilis is a sexually transmitted disease. Blood transfusion and blood contact are also routes of infection. Patients on long-term hemodialysis are at risk during their therapy. The aim of this study is to investigate the incidence of syphilis in hemodialysis patients, possible nosocomial infection and methods of treatment. MATERIALS AND METHODS: A total of 556 uremic patients on maintenance hemodialysis at our hospital on June 1996 were enrolled in the study. They all received syphilis screening tests. The rapid plasma reagin (RPR) test was used as the primary screening tests and Treponema pallidum hemagglutination assay (TPHA) test as the confirmation test. According to the test results, patients were classified into false and true-positive groups. The titer of both tests were recorded. The patients in the true-positive group were further divided into the untreated and treated group depending on whether they had already received treatment. The serial change of RPR test titer of the treated group was reviewed. RESULTS: Thirty-one patients (5.6%) had positive RPR test results and 10 patients (1.8%) had false-positive results. The titers of both RPR and TPHA tests were rather low in the positive groups. Most of the confirmed syphilis patients were asymptomatic and diagnosed serologically. In the treated group, the RPR test titer did not show significant decline and no seroconversion was noted after treatment. CONCLUSION: We observed that infectious syphilis patients exist in our hemodialysis unit and survey for this disease is necessary. The titers of both positive RPR and TPHA tests are low. Most diagnosed patients had latent syphilis, and serologic response to treatment is probably the same as in general population.

Aged↗

PubMed1998

Spontaneous cellulitis in adults with idiopathic nephrotic syndrome.

BACKGROUND: Susceptibility to infection is a common problem in a patient with nephrotic syndrome. The spontaneous cellulitis is not uncommon in pediatric patients with nephrotic syndrome, whereas there have been few cases reported in adults. In order to clarify the clinical course of this complication, we present 17 adult idiopathic nephrotic patients with spontaneous cellulitis. MATERIALS AND METHODS: A series of 17 adult idiopathic nephrotic patients with spontaneous cellulitis were retrospectively reviewed in Chang Gung Memorial Hospital, Kaohsiung from 1986 through 1996. We analyzed their physical conditions, clinical manifestations, and outcome. All patients received renal biopsies and had pathologic diagnoses. RESULTS: The medical records of 17 patients were collected, 12 men and 5 women, with ages ranging from 16 to 63 years (mean 29.5 years). The pathologic diagnoses of renal biopsies included minimal change disease (13/17), membranous glomerulonephritis (2/17), mesangioproliferative glomerulonephritis (1/17) and focal/segmental glomerulosclerosis (1/17). All patients had generalized edematous state. The clinical presentations of these patients were variable. The mean serum albumin and daily urinary protein excretion were 1.28+/-0.64 g/dl and 8.75+/-5.16 g, respectively. The results of blood cultures were E. coli (3/17), Gram-negative bacilli (1/17), Streptococcus viridans (1/17), Streptococcus pneumoniae (1/17) and no growth (11/17). All patients responded to antibiotic treatment except one patient who died due to overwhelming sepsis. CONCLUSION: The related factors of spontaneous cellulitis in patients with nephrotic syndrome are edematous skin, hypoalbuminemia, immunosuppressive drugs and defective immunity. Our patients had accordant conditions. The prognosis was good if diagnosis and treatment are made early.

Adolescent↗

PubMed1998

Early recognition of unsuspected malignant hyperthermia and successful management of serve myoglobinuric renal failure in subsequent rhabdomyolysis: a case report.

Malignant hyperthermia (MH) is a rare inherited disorder of skeletal muscle, its inheritance being autosomal dominant and its mutant gene located on chromosome 19. MH is occasionally observed during general anesthesia when using some special triggering agents. In the susceptible patient, it presents with a fulminant skeletal muscle hypermetabolic crisis and proceeds to serve rhabdomyolysis. Once rhabdomyolysis is established, acute renal failure is not an inevitable consequence, yet it is the fatal complication if the condition is not appropriately managed. We describe a case of acute renal failure in the setting of rhabdomyolysis in unsuspected MH, resulting in full recovery after intermittent hemodialysis. In this case, we emphasize the importance of early recognition of MH and the favorable prognosis of subsequent myoglobinuric renal failure if treated appropriately.

Acute Kidney Injury↗

PubMed1997

Epidural meperidine after cesarean section: the effect of diluent volume.

We investigated the effect of diluent volume on analgesia and systemic absorption from epidural meperidine after cesarean section in a randomized, double-blind study. At the first request for postoperative analgesia, 36 parturients were given epidural meperidine 25 mg diluted with saline to either 2 mL (12.5 mg/mL), 5 mL (5 mg/mL), or 10 mL (2.5 mg/mL). Visual analog pain scores measured in the first 30 min were greater in the 2-mL group compared with both the 5-mL group (P = 0.028) and the 10-mL group (P = 0.031). Onset of analgesia (time for visual analog pain scores to decrease by 50%) was also slower in the 2-mL group (17.5 min) compared with the 5-mL group (9 min; P = 0.015) and the 10-mL group (12 min; P = 0.003); there were no differences between the 5-mL group and the 10-mL group. Duration of analgesia and plasma concentrations of meperidine were similar among groups. No adverse side effects were recorded. Previous work has suggested that injection of epidural opioids in large volumes increases the potential risk of respiratory depression from cephalad spread of the drug. Therefore, we conclude that analgesia is optimum when epidural meperidine is administered diluted to 5 mL.

Absorption↗