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S M Yeong

Publications and source records attributed to S M Yeong.

5 recordsLinked to original sources

Effect of remifentanil compared with fentanyl on intraocular pressure after succinylcholine and tracheal intubation.

Rapid sequence induction using succinylcholine is associated with an increase in intraocular pressure (IOP). This may lead to loss of ocular contents in open globe injuries. No method has previously been shown to prevent this increase in IOP. We investigated whether remifentanil, an ultra-short-acting opioid, could attenuate this increase in IOP during rapid sequence induction of anaesthesia. Forty-five patients were randomized blindly to receive remifentanil 1 microgram kg-1, fentanyl 2 micrograms kg-1 or placebo 1 min before thiopental, succinylcholine and tracheal intubation. IOP and haemodynamic variables were measured before, 1 min after the test solution, 30 s after thiopental, 30 s after succinylcholine, immediately after intubation and then every 3 min for 9 min. Remifentanil obtunded the increase in IOP after succinylcholine and intubation, so it could be suitable for use in open globe injuries.

Adult↗

Intrapartum fetal oxygen saturation monitoring in a busy labour ward.

OBJECTIVE: To measure the ease of use of a fetal pulse oximeter in a busy labour ward. DESIGN: Descriptive study in the Labour Ward, National University Hospital, Singapore, involving 145 labouring women with singleton pregnancies, and fetuses in cephalic presentation, with cervical dilatation >2 cm and amniotic membranes ruptured. RESULTS: Placement was comfortable. Oxygen saturation (SpO2) readings were obtained in 127 women (87.5%). Adequate readings were obtained a median of 69% of the time the transducer was in situ. SpO2 values in the last 10 min prior to delivery correlated poorly with parameters of neonatal outcome. CONCLUSION: The Nellcor N-400 fetal pulse oximeter and FS14 fetal sensor is a feasible method of intrapartum fetal monitoring in a busy labour ward and is acceptable to labouring women.

Female↗

Fetal oxygen saturation during labour.

OBJECTIVE: To derive oxygen saturation by pulse oximetry (SpO2) values at each cervical dilation in labour in fetuses with normal neonatal outcome. PARTICIPANTS: One hundred and forty-five women at term in established labour with ruptured membranes and cervical dilation at least 2 cm who had normal delivery outcome. The infants had 5 minute Apgar scores > or = 7, birthweight > or = 2500 g, umbilical cord artery pH > or = 7.15 and did not require assisted ventilation or admission to neonatal intensive care. METHODS: Women were monitored continuously with cardiotocography and fetal pulse oximetry using the Nellcor N-400 fetal pulse oximeter and FS-14 fetal oxisensor till delivery. Labour was managed according to established protocol without recourse to SpO2 readings. RESULTS: There was a wide range of SpO2 values during labour in fetuses with normal outcome. Mean values averaged 50% +/- 10% throughout the first stage of labour, with lower ranges of SpO2 values above 30%. There was no significant difference in SpO2 readings at different cervical dilatations in the first stage of labour. Mean SpO2 values in the last 10 minutes before delivery were also not significantly different from those in the first stage of labour. CONCLUSION: The range of SpO2 in 115 healthy fetuses during normal labour was wide, but always above 30%. There was no trend of SpO2 values in this study of 115 fetuses with normal neonatal outcome.

Apgar Score↗

Penetrating keratoplasty in the Singapore National Eye Centre and donor cornea acquisition in the Singapore Eye Bank.

We analyzed all penetrating keratoplasties performed in the Singapore National Eye Centre from 1 January 1991 to 31 December 1995, using records of the Singapore Eye Bank Registry, evaluating the indications, complications, causes of graft failure, visual outcome and graft survival rate. We also looked into donor cornea acquisition in the Singapore Eye Bank and its influence on the development of corneal transplantation in the Singapore National Eye Centre. A total of 327 penetrating keratoplasties were performed during the 5-year period. Bullous keratopathy was an indication in 26.3% of cases. Of these, aphakic bullous keratopathy accounted for 11.6% of all cases, while pseudophakic bullous keratopathy accounted for 11.3%. Other indications were regrafts (11.9%), corneal dystrophies (10.4%), traumatic corneal scarring (10.1%) and keratoconus (9.8%). Graft rejection was a complication in 20% of all cases. Of these, 40.9% led to graft failure. Other major complications were raised intraocular pressure (18%), epithelium-related problems (7.3%), wound dehiscence (4.3%), cataract (3.3%) and microbial keratitis (3.1%). The main causes of graft failure were graft rejection (8.2%), endothelial failure (2.4%), infection (2.4%) and glaucoma (2.1%). Of the 327 grafts, 40.3% achieved best corrected visual acuity of 6/12 or better; 70.8% achieved vision of 6/24 or better. The overall graft survival rate was 82.3% after a mean follow-up period of 2 years. Donor corneas for the penetrating keratoplasties were obtained from foreign eye banks as well as locally, with the local donation rate steadily increasing from 1991 to 1996, with the establishment of proper eye banking facilities and the Singapore Eye Bank. These results show that the indications and outcome of penetrating keratoplasty in the Singapore National Eye Centre are similar and comparable to that of other centres with established corneal grafting programmes. The establishment of the Singapore Eye Bank has ensured the proper co-ordination of acquisition of donor material which has been vital to the development of corneal transplantation in the Singapore National Eye Centre.

Adolescent↗