METHODS: Patients (n = 94) scheduled for gynaecological laparotomy received i.v. fentanyl infusion (3 μg/kg/h) after induction of general anaesthesia. Post-operative fentanyl requirements were quantified by using a patient-controlled analgesia and the number of i.v. fentanyl rescue analgesia required were recorded. Pain control was assessed using visual analogue scores (VAS) and fentanyl's adverse effects were documented. CYP3A4*4, CYP3A4*5 and CYP3A4*18 alleles of cytochrome P450 3A4 were identified by polymerase chain reaction-restriction fragment length polymorphism. Differences in fentanyl requirements, VAS scores and adverse effects among the various genotypes were compared.
RESULTS AND DISCUSSION: No CYP3A4*4 and CYP3A4*5 alleles were detected. Eighty-nine patients (94·7%) were wild-type, five (5·3%) were heterozygous and none was homozygous. No significant difference was demonstrated between the genotype groups in terms of fentanyl consumption, pain control and adverse effects.
WHAT IS NEW AND CONCLUSION: CYP3A4*4 and CYP3A4*5 are rare in the Malaysian Malay population. Genetic polymorphism of CYP3A4*18 may not play an important role in influencing postoperative fentanyl requirements.
DESIGN: Serum intact parathormone (PTH) concentrations were measured on samples taken before and during a variable-rate tri-sodium citrate infusion designed to 'clamp' the whole blood ionised calcium concentration 0.20 mmol L-1 below baseline for 120 min.
SUBJECTS: Six Malaysian patients aged 17-42 years with acute malaria, four of whom were restudied in convalescence, and 12 healthy controls aged 19-36 years.
MAIN OUTCOME MEASURES: Whole-blood ionised calcium and serum intact PTH concentrations.
RESULTS: The mean (SD baseline ionised calcium was lower in the malaria patients than in controls (1.09 +/- 0.06 vs. 1.18 +/- 0.03 mmol L-1, respectively; P = 0.01) but PTH concentrations were similar (3.0 +/- 1.8 vs. 3.3 +/- 1.3 pmol L(-1); P = 0.33). Target whole-blood ionised calcium concentrations were achieved more rapidly in the controls than the patients (within 15 vs. 30 min) despite significantly more citrate being required in the patients (area under the citrate infusion-time curve 0.95 (0.25 vs. 0.57 +/- 0.09 mmol kg-1; P < 0.01). The ratio of the change in serum PTH to that in ionised calcium (delta PTH/ delta Ca2+), calculated to adjust for differences in initial rate of fall of ionised calcium, was similar during the first 5 min of the clamp (132 +/- 75 x 10(-6) vs. 131 +/- 43 x 10(-6) in patients and controls, respectively, P > 0.05), as were steady-state serum PTH levels during the second hour (7.0 +/- 2.2 pmol L-1 in each case). Convalescent patients had normal basal ionised calcium levels but the lowest serum intact PTH levels before and during the clamp, consistent with an increase in skeletal PTH sensitivity after treatment.
CONCLUSIONS: There is a decreased ionised calcium 'set point' for basal PTH secretion but a normal PTH response to acute hypocalcaemia in malaria. Skeletal resistance may attenuate the effects of the PTH response but patients with malaria appear relatively resistant to the calcium chelating effects of citrated blood products.
METHOD: A randomized controlled open-label study was performed at the cardiothoracic intensive care unit of Penang Hospital, Malaysia. A total of 28 patients who underwent cardiac surgeries were randomly assigned to receive either dexmedetomidine or morphine. Both groups were similar in terms of preoperative baseline characteristics. Efficacy measures included sedation scores and pain intensity and requirements for additional sedative/analgesic. Mean heart rate and arterial blood pressure were used as safety measures. Other measures were additional inotropes, extubation time and other concurrent medications.
RESULTS: The mean dose of dexmedetomidine infused was 0.12 [SD 0.03] μg kg⁻¹ h⁻¹, while that of morphine was 13.2 [SD 5.84] μg kg⁻¹ h⁻¹. Dexmedetomidine group showed more benefits in sedation and pain levels, additional sedative/analgesic requirements, and extubation time. No significant differences between the two groups for the outcome measures, except heart rate, which was significantly lower in the dexmedetomidine group.
CONCLUSION: This preliminary study suggests that dexmedetomidine was at least comparable to morphine in terms of efficacy and safety among cardiac surgery patients. Further studies with larger samples are recommended in order to determine the significant effects of the outcome measures.