Risk of autistic disorder after exposure to general anaesthesia and surgery: a nationwide, retrospective matched cohort study.

BACKGROUND: Deficits of learning, memory and cognition have been observed in newborn animals exposed to general anaesthetics. However, conclusions from clinical studies conducted in humans to investigate the relationship between anaesthesia and neurodevelopmental disorders have been inconsistent. Autistic disorder is typically recognised earlier than other neurobehavioural disorders. Although certain genes apparently contribute to autistic disorder susceptibility, other factors such as perinatal insults and exposure to neurotoxic agents may play a crucial role in gene-environmental interaction. OBJECTIVE: This study was designed to investigate the association of exposure to general anaesthesia/surgery with autistic disorder. We hypothesised that exposure to general anaesthesia and surgery before 2 years of age is associated with an increased risk of developing autistic disorder. DESIGN: A retrospective matched-cohort study. SETTING: A medical university. Data from the National Health Insurance Research Database of Taiwan from 2001 to 2010 were analysed. PATIENTS: The birth cohort included 114,435 children, among whom 5197 were exposed to general anaesthesia and surgery before the age of 2 years. The 1 : 4 matched controls comprised 20,788 children. MAIN OUTCOME MEASURES: The primary endpoint was the diagnosis of autistic disorder after the first exposure to general anaesthesia and surgery. RESULTS: No differences were found in the incidence of autistic disorder between the exposed group (0.96%) and the unexposed controls (0.89%) (P = 0.62). Cox proportional regression showed that the hazard ratio of exposure to general anaesthesia and surgery was 0.93 [95% confidence interval (95% CI) 0.57 to 1.53] after adjusting for potential confounders. Age at first exposure did not influence the risk of autistic disorder. No relationship was found between the total number of exposures and the risk of autistic disorder. CONCLUSION: Exposure to general anaesthesia and surgery before the age of 2 years age at first exposure and number of exposures were not associated with the development of autistic disorder.

Exposure to general anesthesia in early life and the risk of attention deficit/hyperactivity disorder development: a nationwide, retrospective matched-cohort study.

BACKGROUND: Postnatal exposure to anesthetics can cause neural apoptosis and degeneration in animals, but results from studies conducted on humans were discordant. Previous studies contained no information on the relationship between neurobehavioural disorders and anesthesia exposure in Asian children. We conducted a retrospective matched-cohort study in Taiwan to investigate the association of early life anesthesia exposure with risk of attention deficit/hyperactivity disorder (ADHD). METHODS: Data were obtained from the National Health Insurance Research Database of Taiwan. Children born between January 1, 2001 and December 31, 2005 were included. Each child with anesthesia exposure before 3 years of age was matched to four unexposed children. Observation was concluded on December 31, 2010. Proportional hazards regression was used to assess the association of anesthesia exposure with ADHD. Analyses were also made based on exposure number and age at the time of first exposure. RESULTS: This matched-cohort comprised of 16 465 children, among which 3293 were exposed to general anesthesia before age 3 years. The adjusted hazard ratio of developing ADHD was 1.06 (95% CI: 0.86,1.31) for general anesthesia exposure. The adjusted hazard ratio of developing ADHD for single and multiple exposures were 1.11 (95% CI: 0.88, 1.41) and 0.96 (95% CI: 0.71,1.31), respectively. No trend of increasing risk was noted based on age at the time of first exposure. CONCLUSIONS: Exposure to general anesthesia before 3 years of age was not associated with ADHD.

The effectiveness of clinical problem-based learning model of medico-jurisprudence education on general law knowledge for Obstetrics/Gynecological interns.

OBJECTIVE: The effective education method of medico-jurisprudence for medical students is unclear. The study was designed to evaluate the effectiveness of problem-based learning (PBL) model teaching medico-jurisprudence in clinical setting on General Law Knowledge (GLK) for medical students. MATERIALS AND METHODS: Senior medical students attending either campus-based law curriculum or Obstetrics/Gynecology (Ob/Gyn) clinical setting morning meeting from February to July in 2015 were enrolled. A validated questionnaire comprising 45 questions were completed before and after the law education. RESULTS: The interns attending clinical setting small group improvisation medico-jurisprudence problem-based learning education had significantly better GLK scores than the GLK of students attending campus-based medical law education course after the period studied. CONCLUSION: PBL teaching model of medico-jurisprudence is an ideal alternative pedagogy model in medical law education curriculum.

Anesthetic management of dental procedures in mentally handicapped patients.

BACKGROUND: Providing dental care to a mentally handicapped patient is a challenge to both dentist and anesthesiologist. This study was aimed to describe the anesthetic methods which were used to facilitate dental treatments in mentally handicapped patients at a medical university hospital in Taiwan during a three-year period. METHODS: The data referring to anesthetic techniques to facilitate dental treatments during the period from Dec. 1, 1997 to Nov. 30, 2000 were retrospectively collected. In the period, there were four different anesthetic techniques in application: nasal mask technique combined with intravenous sedation, total intravenous anesthesia, laryngeal mask intubating general anesthesia and endotracheal intubating general anesthesia. Basic characteristics of patients were compared with student t-test between groups according to anesthetic technique used. Intraoperative and postoperative complications and complaints collected were analyzed by chi-square test between anesthetic techniques. P value less than 0.05 was considered statistically significant. RESULTS: The anesthetic records of 1201 mentally handicapped patients who underwent dental procedures over the three-year period were reviewed. Anesthesia was accomplished with nasal mask technique combined with intravenous sedation in 10 patients, with intravenous anesthesia in 112 patients, with endotracheal intubation anesthesia in 249 patients and with reinforced laryngeal mask anesthesia in 826 patients. Four patients were excluded from study because of changing of anesthetic method during the dental procedure. The use of nasal mask combined with intravenous sedation and intravenous anesthesia caused a higher incidence of intraoperative hypoxemia (P < 0.05) in comparison with the groups of endotracheal intubation anesthesia and reinforced laryngeal mask anesthesia. Although patients anesthetized by intravenous anesthetics had less postoperative complaints or complications but the difference was not statistically significant (P > 0.05) when group comparison was made. Patients who were anesthetized by volatile agents through endotracheal tube had the highest rate of postoperative complication although the difference was of no significance (P > 0.05) when comparison between groups was made. CONCLUSIONS: We provided four different anesthetic methods for 1197 mentally handicapped patients who underwent dental procedures in three years. All anesthetic methods had their advantages and disadvantages. Using reinforced laryngeal mask or endotracheal intubation for general anesthesia to facilitate dental procedures for such patients had greater intraoperative safety than other two methods. However, less postoperative complaints or complications were revealed with the methods of nasal mask combined with intravenous sedation and intravenous anesthesia.

Inappropriate use of standard error of the mean when reporting variability of study samples: a critical evaluation of four selected journals of obstetrics and gynecology.

OBJECTIVE: The study was designed to investigate the frequency of misusing standard error of the mean (SEM) in place of standard deviation (SD) to describe study samples in four selected journals published in 2011. Citation counts of articles and the relationship between the misuse rate and impact factor, immediacy index, or cited half-life were also evaluated. MATERIALS AND METHODS: All original articles in the four selected journals published in 2011 were searched for descriptive statistics reporting with either mean ± SD or mean ± SEM. The impact factor, immediacy index, and cited half-life of the journals were gathered from Journal Citation Reports Science edition 2011. Scopus was used to search for citations of individual articles. The difference in citation counts between the SD group and SEM group was tested by the Mann-Whitney U test. The relationship between the misuse rate and impact factor, immediacy index, or cited half-life was also evaluated. RESULTS: The frequency of inappropriate reporting of SEM was 13.60% for all four journals. For individual journals, the misuse rate was from 2.9% in Acta Obstetricia et Gynecologica Scandinavica to 22.68% in American Journal of Obstetrics & Gynecology. Articles using SEM were cited more frequently than those using SD (p = 0.025). An approximate positive correlation between the misuse rate and cited half-life was observed. CONCLUSION: Inappropriate reporting of SEM is common in medical journals. Authors of biomedical papers should be responsible for maintaining an integrated statistical presentation because valuable articles are in danger of being wasted through the misuse of statistics.

The relation between oxygen consumption and the equilibrated inspired oxygen fraction in an anesthetic circle breathing system: a mathematic formulation & laboratory simulations.

Measuring a patients' oxygen consumption (VO2) is valuable in critical care and during anesthesia. Up to now, there has been no satisfactory equation describing the relation between the VO2, the fresh gas, and F(I)O(2) in a semi-closed circle breathing system. By adopting a "volume-weighted average concentration" approach and stepwise calculations, we have proposed an equation. We constructed a model with known simulated O(2) consumption ((SIM)VO2) to test our equation and two other previous methods (Biro's and Azami's). After 32 different laboratory scenarios, the %-error of the calculated VO2 ((CAL)VO2) from our method is -4.0 +/- 2.9%, which is significantly better than those from Azami's method (-8.8 +/- 6.2%, p < 0.01) and from Biro's method (-27.4 +/- 5.1%, p < 0.01). We also produce a Bland-Altman analysis of our (CAL)VO2 and (SIM)VO2. The 95% limits of agreement are -18.6-3.3 mL/min with a mean bias of -7.7 mL/min, which shows a good agreement. Our equation also explains the difference between F(I)O(2) and the oxygen concentration of the fresh gas in a semi-closed circle breathing system.