Difficult and failed intubation in Caesarean general anaesthesia: a four-year retrospective review

INTRODUCTION@#General anaesthesia is associated with higher maternal morbidity and mortality when compared with regional anaesthesia, related mainly to failure of intubation, hypoxia and aspiration. The aim of this retrospective review was to define the incidence of failed and difficult intubation in parturients undergoing general anaesthesia for Caesarean delivery at a high-volume obstetric hospital in Singapore.@*METHODS@#All parturients who underwent Caesarean delivery under general anaesthesia from 2013 to 2016 were identified and their medical records were reviewed to extract pertinent data. Difficult intubation was defined as 'requiring more than one attempt at intubation or documented as such, based on the opinion of the anaesthetist'. A failed intubation was defined as 'inability to intubate the trachea, with subsequent abandonment of intubation as a means of airway management'.@*RESULTS@#Records of 660 Caesarean sections under general anaesthesia were extracted. The mean age of the parturients was 32.1 ± 5.5 years and the median body mass index was 27.5 (interquartile range 24.6-31.1) kg/m2. Rapid sequence induction with cricoid pressure was employed for all patients, with thiopentone and succinylcholine being administered for 91.2% and 98.1% of patients, respectively. There were 33 difficult intubations among 660 patients, yielding an incidence of 5.0%. Junior trainees performed about 90% of all intubations and 28 (84.8%) out of 33 difficult intubations. Repeat intubations were performed by senior residents/fellows (57.1%) and consultants (14.3%). No instance of failed intubation was reported.@*CONCLUSION@#The local incidence of difficult obstetric intubation was one in 20. No failure of intubation was observed.

Delphi consensus on the American Society of Anesthesiologists’ physical status classification in an Asian tertiary women’s hospital / 대한마취과학회지

Background@#The American Society of Anesthesiologists (ASA) score is generated based on patients’ clinical status. Accurate ASA classification is essential for the communication of perioperative risks and resource planning. Literature suggests that ASA classification can be automated for consistency and time-efficiency. To develop a rule-based algorithm for automated ASA classification, this study seeks to establish consensus in ASA classification for clinical conditions encountered at a tertiary women’s hospital. @*Methods@#Thirty-seven anesthesia providers rated their agreement on a 4-point Likert scale to ASA scores assigned to items via the Delphi technique. After Round 1, the group’s collective responses and individual item scores were shared with participants to improve their responses for Round 2. For each item, the percentage agreement (‘agree’ and ‘strongly agree’ responses combined), median (interquartile range/IQR), and SD were calculated. Consensus for each item was defined as a percentage agreement ≥ 70%, IQR  1.0, and SD < 1.0. @*Results@#All participants completed the study and none had missing data. The number of items that reached consensus increased from 25 (51.0%) to 37 (75.5%) in the second Delphi round, particularly for items assigned ASA scores of III and IV. Nine items, which pertained to alcohol intake, asthma, thyroid disease, limited exercise tolerance, and stable angina, did not reach consensus even after two Delphi rounds. @*Conclusions@#Delphi consensus was attained for 37 of the 49 study items (75.5%), facilitating their incorporation into a rule-based clinical support system designed to automate the prediction of ASA classification.

Implementation of an obstetric cell salvage service in a tertiary women's hospital

<p><b>INTRODUCTION</b>Intraoperative cell salvage (ICS) is an important aspect of patient blood management programmes. An ICS service was introduced at KK Women's and Children's Hospital, Singapore, from 2 May 2011 to 30 April 2013 to aid in the management of massive obstetric haemorrhage.</p><p><b>METHODS</b>With support from the Ministry of Health's Healthcare Quality Improvement and Innovation Fund, a workgroup comprising obstetricians, anaesthetists and nursing staff was formed to develop training requirements, clinical guidelines and protocols for implementing ICS using the Haemonetics Cell Saver 5. Pregnant women with an anticipated blood loss of > 1,000 mL during Caesarean delivery, a baseline haemoglobin level of < 10 g/dL, rare blood types and who had refused donor blood were recruited to the service after obtaining informed consent.</p><p><b>RESULTS</b>A total of 11 women were recruited to the ICS service; the primary indications were placenta praevia and placenta accreta. Median blood loss in these 11 patients was 1,500 (range 400-3,000) mL. In four patients, adequate autologous blood was collected to initiate processing and salvaged, processed blood was successfully reinfused (mean 381.3 [range 223.0-700.0] mL). Median blood loss among these four patients was 2,000 (range 2,000-3,000) mL. No adverse event occurred following autologous transfusion. Mean immediate postoperative haemoglobin level was 8.0 (range 7.1-9.4) g/dL.</p><p><b>CONCLUSION</b>The implementation of an obstetric ICS service in our institution was successful. Future studies should seek to address the cost-effectiveness of ICS in reducing allogeneic blood utilisation.</p>