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K L Cheung

Publications and source records attributed to K L Cheung.

At least 73 records · Page 4Linked to original sources
PubMed1998

Double blind, randomised, placebo controlled study of oral vancomycin in prevention of necrotising enterocolitis in preterm, very low birthweight infants.

AIMS: To evaluate the effectiveness of oral vancomycin in the prophylaxis of necrotising enterocolitis in preterm, very low birthweight infants. METHODS: A prospective, double blind, randomised, placebo controlled study in a tertiary referral centre of a university teaching hospital was conducted on 140 very low birthweight infants consecutively admitted to the neonatal unit. The babies were randomly allocated to receive oral vancomycin (15 mg/kg every 8 hours for 7 days) or an equivalent volume of placebo solution. Prophylaxis was started 24 hours before the start of oral feeds. All suspected cases of necrotising enterocolitis were investigated with a full sepsis screen and serial abdominal radiographs. Necrotising enterocolitis was diagnosed and staged according to modified Bell's criteria. RESULTS: Nine of 71 infants receiving oral vancomycin and 19 of 69 infants receiving the placebo solution developed necrotising enterocolitis (p = 0.035). Infants with necrotising enterocolitis were associated with a significant increase in mortality (p = 0.026) and longer duration of hospital stay (p = 0.002). CONCLUSIONS: Prophylactic oral vancomycin conferred protection against necrotising enterocolitis in preterm, very low birthweight infants and was associated with a 50% reduction in the incidence. However, widespread implementation of this preventive measure is not recommended, as it would only be effective in necrotising enterocolitis caused by Gram positive organisms and could increase the danger of the emergence of vancomycin resistant or dependent organisms. Its use should be restricted to a high prevalence nursery for a short and well defined period in a selected group of high risk patients.

Administration, Oral↗
PubMed1998

Risk factors for development of acute renal failure (ARF) requiring dialysis in patients undergoing cardiac surgery.

Acute renal failure (ARF) is one of the major complications after cardiopulmonary bypass for open heart operations. The present study was undertaken to identify the risk factors for the development of ARF following cardiopulmonary bypass (CPB). Four hundred and forty-seven consecutive patients who underwent open heart procedures from July 1994 to June 1995 were analyzed retrospectively. Their mean age was 55.6 +/- 14.2 (SD) years (range, 18 to 80). Dialysis was instituted whenever a patient exhibited inadequate urine output (<0.5 mL/kg/hr) for 2 to 3 hours despite correction of hemodynamic status and diuretic therapy, especially if fluid overload, hyperkalemia, or metabolic acidosis were also present. Twenty variables were analyzed by univariate analysis; these included nine preoperative variables--age, sex, hypertension, atherosclerosis, diabetes mellitus, left ventricular end-diastolic dimension (LVEDD) >5 cm, preoperative congestive heart failure, renal insufficiency (serum creatinine > or =130 micromol/L on two occasions), and sepsis--10 intraoperative variables--duration of CPB, redo procedures, emergency surgery, use of intraaortic balloon pump (IABP) in operating room, use of gentamicin, use of ceftriaxone, use of sulbactam/ampicillin, requirement of deep hypothermic circulatory arrest, duration of low mean perfusion pressure (mean pressure <50 mmHg for more than 30 minutes), operation on multiple valves--and one postoperative variable--significant hypotension (systolic blood pressure less than 90 mmHg for more than 1 hour). Significant variables or the variables having a trend (p<0.1) to be associated with ARF were included in stepwise multiple logistic regression analyses. Three regression analyses were performed separately. The incidence of ARF requiring dialysis in the study period was 15.0%. Significant risk factors for whole group of patients (regression I) were preoperative renal insufficiency (p<0.0001), postoperative hypotension (p<0.0001), cardiopulmonary bypass time more than 140 min (p<0.005), preoperative congestive heart failure (p<0.01), and history of diabetes mellitus (p<0.01). The risk factors in the valve group of patients (regression II) were preoperative renal insufficiency (p<0.0001) and postoperative hypotension (p<0.05). Risk factors in the CABG patients (regression III) were postoperative hypotension (p=0.0001), CPB time more than 140 min (p<0.05), preoperative renal insufficiency (p<0.05), and age (p<0.05). The authors conclude that preoperative renal insufficiency and postoperative hypotension are the most important independent risk factors for ARF in postcardiac surgical patients. In addition, CPB time greater than 140 minutes and old age are also independent risk factors for ARF in CABG patients. CPB time more than 140 minutes, history of diabetes mellitus, and preoperative congestive heart failure are independent risk factors for development of ARF in our total group of patients. These findings may have important clinical implications in the prevention of ARF in postcardiac surgical patients.

Acute Kidney Injury↗
PubMed1998

Delivery of salbutamol to nonventilated preterm infants by metered-dose inhaler, jet nebulizer, and ultrasonic nebulizer.

To identify the most efficient device for the delivery of bronchodilator aerosol to nonventilated preterm infants with chronic lung disease, we compared the metered dose inhaler (MDI) used in conjunction with a non-valved spacer, an ultrasonic nebulizer with a small medication cup, and two jet nebulizers. The subjects were enrolled in two double-blind randomized crossover studies. In study A (n=10), each infant was given a nominal dose of 200 microg of salbutamol by a MDI (Ventolin) at 4 h intervals, and in random sequence via an Aerochamber (Neonatal Aerochamber) with its one-way valve removed, an ultrasonic nebulizer with a small cone-shaped medication cup (Siemens Electronics), and a jet nebulizer (Side-stream). Their functional residual capacity (FRC) and static respiratory system mechanics were measured before, and at 15, 30, 60, and 120 min after aerosol delivery. Study B (n=10) was carried out in an identical manner, but with a different jet nebulizer (Hudson). In both studies, administration of salbutamol aerosol via the MDI Aerochamber or ultrasonic nebulizer resulted in a significantly greater reduction in respiratory system resistance than via jet nebulizers. Furthermore, the use of MDI Aerochamber or ultrasonic nebulizer was associated with a greater degree of post-treatment tachycardia and improvement in FRC. The bronchodilating effect of salbutamol delivered via the ultrasonic nebulizer appeared to be slightly greater than that via the MDI-Aerochamber, receiving significance only in Study B. We conclude that both the metered-dose inhaler used with a nonvalved Aerochamber and the ultrasonic nebulizer with a small medication cup are both more efficient than the jet nebulizers in preterm infants.

Albuterol↗
PubMed1997

Biochemical investigation of young hospitalized Chinese children: results over a 7-year period.

During the seven years from January 1989 to December 1995, we investigated 2,269 Chinese infants and young children for metabolic disorders in Hong Kong. These young patients, all aged under 4 years and originated from southern China, were ill with no apparent cause and had clinical manifestations suggestive of inherited metabolic diseases. A spot urine and a plasma sample were obtained from each patient for biochemical analysis, including urinary organic acid identification and plasma amino acid analysis. Six cases of mucopolysaccharidosis, four multiple carboxylase deficiency, three 2-methylacetoacetyl CoA thiolase deficiency, two methymalonic aciduria, one glutaric aciduria type I, one glutaric aciduria type II, one a-oxoglutaric aciduria, and one case of orotic aciduria were detected. There were also single suspected cases of medium-chain acyl-CoA dehydrogenase deficiency and isovaleric aciduria. No primary amino acid disorder, such as phenylketouria and maple syrup urine disease, has been detected. Our results suggest that a different pattern of inherited metabolic diseases exists in the southern Chinese when compared with the Chinese in other regions of China.

Child, Preschool↗
PubMed1997

Aerosol delivery to non-ventilated infants by metered dose inhaler: should a valved spacer be used?

In a randomized double-blind cross-over study on 20 spontaneously breathing, oxygen-dependent preterm infants who had received positive pressure ventilation for respiratory distress syndrome, we tested the hypothesis that the one-way non-rebreathing valves of aerosol spacer devices might impair rather than enhance the delivery of aerosols to small infants by metered dose inhalers (MDI). Ten infants were given 2 doses (200 micrograms/dose) of MDI albuterol through a neonatal Aerochamber 4 h apart. At random sequence, one dose was delivered with the non-rebreathing valve of the Aerochamber in place; for the other dose, the valve had been removed. The experiment was repeated on another ten infants using a different spacer device (Babyhaler) with or without its one-way inspiratory valve removed. During the first hour following aerosol administration, use of the non-valved spacers was associated with a significantly greater degree of tachycardia in both groups, and also lower transcutaneous carbon dioxide tension in the Aerochamber group. All infants showed a reduction in respiratory system resistance and an improvement in functional residual capacity following albuterol treatment. In both groups, maximum reduction in respiratory system resistance, recorded 30 min after aerosol delivery, was significantly greater following the use of the non-valved spacers (Aerochamber: 51.2 +/- 3.1% vs. 35.0 +/- 2.8%, P < 0.0001; Babyhaler: 38.8 +/- 2.3% vs. 19.2 +/- 1.4%, P < 0.0001) than following the use of the spacers with a valve. The findings provide indirect evidence supporting our hypothesis and suggest that when the MDI is used to deliver therapeutic aerosols to non-ventilated newborns or small infants, a spacer device without a non-rebreathing valve should be used.

Aerosols↗
PubMed1997

Pregnancy-related gigantomastia. Case report.

The term gigantomastia has been used to describe breast enlargement to extreme size, with sloughing, haemorrhage and infection. The condition is rare and a case of pregnancy-related gigantomastia is reported.

Abortion, Induced↗
PubMed1997

Subcutaneous mastectomy for primary breast cancer and ductal carcinoma in situ.

Subcutaneous mastectomy (SCM) has been performed in 323 patients with invasive breast cancer or ductal carcinoma in situ (DCIS) over the last 20 years. This paper assesses the oncological safety of this operation with particular reference to local recurrences (LR) in the skin flaps. LR was assessed in the 134 patients who did not receive post-operative irradiation to the flaps and were followed up for a minimum of 30 months. The rates of LR were similar for SCM (16%) and for women who underwent simple mastectomy without post-operative irradiation (SM) for invasive cancer (14%) over the same time period, both overall and after prognostic stratification. In DCIS LR was only found in women treated with SCM. Four of the five recurrences (from 33 women) were in the nipple and later in the series patients with microscopic tumour involvement in the nipple received prophylactic irradiation to the nipple only; five patients treated in this way have not suffered LR. Subcutaneous mastectomy followed by insertion of a prosthesis is a safe alternative to mastectomy, since it carries no higher risk of LR. It is the simplest form of reconstruction in those proceeding to silicone implant and has the potential of achieving an excellent cosmetic result. Failure does not compromise the chance of more complex reconstruction procedures.

Adult↗
PubMed1997

The clinical relevance of static disease (no change) category for 6 months on endocrine therapy in patients with breast cancer.

This study reports on the clinical relevance of the static disease (SD) category in 255 breast cancer patients on endocrine therapy. All patients had received first- and second-line endocrine therapy and were assessed for response by the International Union Against Cancer (UICC) criteria. We did not include patients who received first-line endocrine therapy but did not or have not yet proceeded to second-line hormone therapy, e.g. died from rapidly progressive disease, started chemotherapy for rapidly progressive disease, remained in long-term remission on first-line endocrine therapy. We analysed survival from initiation of first-line endocrine therapy by the remission criteria, i.e. complete response (CR), partial response (PR), static disease (SD) or progressive disease (PD), achieved on that therapy. Patients were divided into those with metastatic breast cancer (MBC) and non-metastatic disease. There was no significant difference in survival from starting first-line endocrine therapy between patients who obtained CR, PR or SD: all three groups of patients survived significantly longer than patients who showed PD within 6 months (all P < 0.0001 except CR versus PD [MBC] which was P < 0.002). Equally, for second-line endocrine therapy there was no difference in survival between patients who obtained CR, PR or SD: all three groups (CR, PR and SD) survived significantly longer than PD (all P < 0.0003 except for CR versus PD which was P < 0.003 for non-metastatic and P < 0.059 for MBC). Durable SD appears to be a clinically useful criteria of therapeutic remission.

Aged↗
PubMed1997

Predictors of response to second-line endocrine therapy for breast cancer.

This study reports on factors predicting response to second-line endocrine therapy in 250 patients with breast cancer for which they were assessable for response by the International Union Against Cancer (UICC) criteria. Clinical details relating to first-line endocrine therapy were available for all patients. We have not included in this study patients who received first-line endocrine therapy but did not or have not yet proceeded to second-line hormone therapy--e.g. died from rapidly progressive disease, started chemotherapy for rapidly progressive disease, or remained in long-term remission on first-line endocrine therapy. One hundred and fifty nine patients (72%) achieved remission (objective response and static disease [OR + SD]) on first-line endocrine therapy with a median duration of 19 months. For second-line endocrine therapy the remission rate was 53% (132/225) with a median duration of 15 months. Tumour grade and oestrogen receptor status of the primary tumour were shown to be independent predictors of response to second-line endocrine therapy while response to first-line endocrine therapy was a predictor of the duration of response to second-line endocrine therapy. In the sub-group of patients who showed OR or SD to both first and second-line therapies, there was no correlation between the time to progression (TTP) on first and second-line therapies.

Adult↗
PubMed1997

Eye protection for newborns under phototherapy: comparison between a modified headbox and the conventional eyepatches.

In a randomized trial comparing a modified oxygen headbox with conventional eye patches for protecting the eyes of newborn infants undergoing phototherapy, the use of the headbox did not interfere with phototherapy treatment and was preferred by the nursing staff, as shown by an opinion survey. This, plus our previously reported finding that the headbox was associated with less eye infection, less periorbital skin irritation and less accidental exposure of the eyes due to displacement of the protective devices, suggests that the headbox provides a convenient and inexpensive alternative method of eye protection. The device may be particularly useful in busy and under-staffed neonatal units where vigilant eye care of infants undergoing phototherapy may be difficult.

Attitude of Health Personnel↗
PubMed1997

Erythromycin treatment for gastrointestinal dysmotility in preterm infants.

OBJECTIVE: To report our clinical experience on the use of oral erythromycin for the treatment of severe gastrointestinal dysmotility in preterm infants. METHODOLOGY: A case series study of seven preterm infants (six were very low birthweight) with severe intestinal dysmotility in a tertiary neonatal centre. RESULTS: All responded favourably without adverse effects and tolerated full enteral feeding within 1-2 weeks of the commencement of the drug. CONCLUSIONS: As prolonged total parenteral nutrition carries significant risk of complications, this therapy could be considered in selected preterm infants who fail to establish enteral feeding after an extended period, and in whom an anatomically obstructive lesion of the gastrointestinal tract has been excluded. Meanwhile, we would caution against the widespread implementation of this therapeutic approach until formal evaluation by randomized controlled trials have established the exact role of erythromycin, or its analogues, in the treatment of intestinal dysmotility in preterm infants.

Erythromycin↗
PubMed1997

Central diabetes insipidus in a newborn with deletion of chromosome 7q.

We report an infant with midline craniofacial defects and holoprosencephaly due to chromosome 46, XY, del (7) (pter-->q34) who presented at 1 week of age with central diabetes insipidus. The importance of hypothalamic-pituitary endocrine investigation in patients with this syndrome, and more generally, in patients with midline craniofacial malformation or holoprosencephaly is emphasized. As infants with chromosome 7q deletion bear close phenotypic resemblance to infants of Trisomy 13, chromosomal confirmation and karyotype banding is mandatory to establish an accurate diagnosis and for genetic counselling of their parents.

Abnormalities, Multiple↗
PubMed1997

Omental transposition flap for gross locally recurrent breast cancer.

BACKGROUND: The omentum has been employed to cover the defect produced after resection of gross breast cancer recurrence for nearly three decades. METHODS: A series of 11 patients undergoing omental transposition flap for very wide resection of gross local recurrence (LR) of breast cancer is reported. The median age was 39 years, with a short interval (median = 21 months) from the treatment of the primary tumour to LR. Local recurrence was gross and predominantly inflammatory. RESULTS: All except one patient had lymphovascular invasion in the recurrent tumour. The omental graft was 100% viable but one patient required re-application of further split-thickness skin graft. The mean hospital stay was 16 days. Two cases of seroma formation were encountered. New recurrence developed around the periphery of the flap in eight patients after a median duration of local control of only 2.5 months. Eight patients died with metastatic disease after a median period of 6 months, six patients with uncontrolled local disease. Five patients were free from LR in over half of their remaining period of life. CONCLUSION: Omentoplasty is a safe and reliable procedure but the length of palliation achieved is often far from satisfactory.

Adult↗
PubMed1997

Randomised controlled trial of colloid or crystalloid in hypotensive preterm infants.

AIM: To compare the efficacy of a colloid (5% albumin) and a crystalloid (isotonic saline) solution for treating hypotension in mechanically ventilated preterm infants. METHODS: Sixty three preterm infants weighing 540 to 1950 g at birth and with gestational ages of 23 to 34 weeks, who developed hypotension (mean arterial pressure < 25, 30, and 35 mm Hg for infants with birthweight < 1, 1-1.49, and 1.5-1.99 kg, respectively) within the first 2 hours of life, were randomly allocated to receive intravenous infusions at 10 ml/kg of either 5% albumin (group 1, n = 32) or isotonic (0.9%) saline (group 2, n = 31). Inotropic support with dopamine infusion was given if the infants remained hypotensive after a total of three infusions (30 ml/kg). Subsequent extra doses of volume expander in the form of 5% albumin was given, depending on the infant's blood pressure. RESULTS: There was no difference in the volume of the test solutions required between the two groups. Outcome, as assessed by the number of infants requiring inotropic support and death or chronic lung disease, did not differ between the groups. After inotropic support, however, group 1 required significantly more volume expander to maintain normal blood pressure (median: 27.5 ml/kg vs 10 ml/kg; P = 0.0187) and had a higher mean (SEM) percentage weight gain within the first 48 hours of life (at 24 hours: 6.3(1.3)% vs 3.3(0.8)%; P = 0.049; at 48 hours: 5.9(1.9)% vs 0.9(1.7)%; P = 0.045). The difference in weight gain was significant at 48 hours even when only those infants not requiring inotropic support or extra 5% albumin were compared (group 1: 1.5(1.5)%, group 2: -4.2(1.1)%; P = 0.027). CONCLUSIONS: Isotonic saline is as effective as 5% albumin for treating hypotension in preterm infants, and it has the additional advantage of causing less fluid retention in the first 48 hours.

Albumins↗
PubMed1997

Randomised controlled trial: comparison of colloid or crystalloid for partial exchange transfusion for treatment of neonatal polycythaemia.

AIM: To compare the efficacy of using isotonic saline (crystalloid) or 5% albumin (colloid) as replacement fluid in partial exchange transfusion (PET) for the treatment of neonatal polycythaemia. METHODS: One hundred and two polycythaemic full term infants were randomly allocated to receive PET with either isotonic saline or 5% albumin. The criteria for PET were: (a) venous haematocrit > or = 0.7; or (b) venous haematocrit 0.65-0.69 with symptoms or signs attributable to polycythaemia. RESULTS: PET with either saline (n = 53) or 5% albumin (n = 50) resulted in a significant and sustained decline in haematocrit up to 24 hours after PET. Although the immediate haemodilution effect of isotonic saline was statistically smaller than that of 5% albumin (decline in haematocrit 19.3% vs 22.8% of pre-PET value), the difference was too small to be of any clinical significance, and the haematocrit at 4 or 24 hours after PET did not differ significantly between the two groups. PET with either replacement fluid was not associated with any complication. The serum sodium and potassium concentrations were not significantly affected by the PET in either group. CONCLUSIONS: Both isotonic saline and 5% albumin are effective when used as replacement fluid in PET for the treatment of neonatal polycythaemia. Isotonic saline, which is cheaper and free of infection, should be the replacement fluid of choice.

Albumins↗
PubMed1997

Diagnosis of late onset neonatal sepsis with cytokines, adhesion molecule, and C-reactive protein in preterm very low birthweight infants.

AIMS: To evaluate the commonly used markers--namely IL-6, TNF alpha, IL-1 beta, C-reactive protein and E-selection for identification of late onset neonatal sepsis; to define the optimal cutoff value for each marker in preterm neonates; to assess whether these markers could assist in early discontinuation of antibiotics in non-infected cases; and to delineate the profile of these markers during systemic infection and in relation to successful treatment. METHODS: Very low birthweight infants in whom clinical sepsis was suspected when they were > 72 hours of age were eligible for study. A full sepsis screen was performed in each episode. Cytokines, C-reactive protein, and E-selectin were serially measured on days 0 (at the time of sepsis evaluation), 1, 2, 4 and 7. The optimal cutoff value for each marker was calculated after minimising the number of misclassified episodes over all possible cutoff values for days 0 and 1. The sensitivity, specificity, positive and negative predictive values for each test and combination of tests for predicting systemic infection were also determined. RESULTS: One hundred and one episodes of suspected clinical sepsis were investigated in 68 infants. Forty five episodes were proved to be infections. The optimal cutoff values were IL-6 31 pg/ml, TNF alpha 17 pg/ml, IL-1 beta 1 pg/ml, C reactive protein 12 mg/l and E-selectin 174 ng/ml. IL-6 had the highest sensitivity (89%) and negative predictive value (91%) for detecting late onset infection on day 0. However, between 24 and 48 hours of onset, C-reactive protein was the best single marker, with an overall sensitivity and specificity of 84% and 96%, respectively. The use of serial and multiple markers in the first 48 hours further enhanced the sensitivity and specificity of these tests. Performing IL-6 and C-reactive protein on day 0, together with either TNF alpha on day 1 or C-reactive protein on day 2, showed the best overall sensitivity (98%) and specificity (91%) for the diagnosis of late onset infection. CONCLUSIONS: Optimal cutoff values for these markers in detecting late onset systemic infection in very low birthweight infants have been defined. Withholding antibiotic treatment at the onset of infection could be fatal and is not recommended, but the concomitant use of IL-6 and C-reactive protein or TNF alpha should allow antimicrobial treatment to be discontinued at 48 hours without waiting for microbiological results, provided that the infants are in good clinical condition.

Biomarkers↗
PubMed1997

A review of nipple discharge in Chinese women.

Nipple discharge was the presenting complaint in 104 patients (1.5%) from a series of 7000 women who were seen in a breast clinic over a 13-year period. Complete follow-up information was available in 66 Chinese patients. The mean age at presentation was 47 years. Twenty-six patients (39%) were postmenopausal. Unilateral discharge (92%) from a single duct (77%) was the main finding. There were five patients (8%) with proven breast cancer; benign duct papilloma was found in 17 patients. Multivariate analysis showed that cancer was most likely in women over the age of 55 (P < 0.05) and when the discharge was bloody (P < 0.05). Ductography was also found to be useful in the diagnosis of duct papilloma (P < 0.02).

Adult↗