OBJECTIVES: (1) Evaluate the four published equations' performance in estimating ionised calcium; (2) Determine the accuracy of calculated ionised and adjusted total calcium in classifying patients according to calcium states; and (3) Identify factors associated with hypocalcaemia in the critically ill population.
MATERIALS AND METHODS: This is a cross-sectional study involving 281 critically ill patients aged 18-80 years of both genders in a Malaysian tertiary intensive care unit. Performance of the four equations was analysed using Bland-Altman difference plot and Passing Bablok regression analysis. Crosstabulation was conducted to assess classification accuracy. Mann-Whitney U or Pearson Chi-Square tests were performed to identify variables associated with hypocalcaemia.
RESULTS: Calculated ionised calcium using all four equations significantly overestimated ionised calcium. Calculated ionised and adjusted total calcium had poor accuracies in classifying hypocalcaemic patients. pH was significantly higher in hypocalcaemics.
CONCLUSION: Calculated ionised and adjusted total calcium significantly overestimate ionised calcium in the critically ill. In this specific population, calcium status should only be confirmed with ionised calcium measured by direct ion-selective electrode (ISE).
METHODS: In two randomised, double-blinded, cross-over or placebo-controlled (caffeine) studies, we measured sixty subjects in eight sessions (n = 30, Male: Female = 1:1 in each study).
RESULTS: We found caffeine increased motor cortex excitability in caffeine naïve subjects. The aftereffects in caffeine naïve subjects were enhanced and prolonged when combined with PAS 25. Caffeine also increased alertness and the motor evoked potentials (MEPs) were reduced under light deprivation in caffeine consumers both with and without caffeine. In caffeine consumers, the time of day had no effect on tACS-induced plasticity.
CONCLUSIONS: We conclude that caffeine should be avoided or controlled as confounding factor for brain stimulation protocols. It is also important to keep the brightness constant in all sessions and study groups should not be mixed with caffeine-naïve and caffeine consuming participants.
SIGNIFICANCE: Caffeine is one of the confounding factors in the plasticity induction studies and it induces different excitability effects in caffeine-naïve and caffeine-adapted subjects. This study was registered in the ClinicalTrials.gov with these registration IDs: 1) NCT03720665 https://clinicaltrials.gov/ct2/results?cond=NCT03720665&term=&cntry=&state=&city=&dist= 2) NCT04011670 https://clinicaltrials.gov/ct2/results?cond=&term=NCT04011670&cntry=&state=&city=&dist=.
METHODS: A cross-sectional study was conducted involving 22 cases of glioma diagnosed intraoperatively from January 2013 until August 2019 in Hospital Universiti Sains Malaysia. The selected tissues were processed for cytology smear and frozen section. The remaining tissues were proceeded for paraffin section. The diagnosis was categorized as either low-grade or high-grade glioma based on cellularity, nuclear pleomorphism, mitotic count, microvascular proliferation and necrosis. The sensitivity and specificity of frozen section and cytology smears were determined based on paraffin section being as the gold standard. The accuracy of both techniques was compared using statistical analysis.
RESULTS: The overall sensitivity and specificity of cytology smear were 100% and 76.9%, respectively. Meanwhile, the sensitivity and specificity of frozen section were 100% and 84.6%. There was no significant difference in diagnostic accuracy between cytology smear and frozen section in glioma (p>0.05).
CONCLUSION: Cytology smears provides an alternative method for frozen section due to good cellularity and morphology on smear. Cytology smear is rapid, inexpensive, small amount of tissue requirement and less technical demand. This finding may benefit to the hospital or treatment centres where frozen section facility is unavailable.