Emergency cricothyroidotomy: an observational study to estimate optimal incision position and length.

BACKGROUND: A vertical incision is recommended for cricothyroidotomy when the anatomy is impalpable, but no evidence-based guideline exists regarding optimum site or length. The Difficult Airway Society guidelines, which are based on expert opinion, recommend an 80-100 mm vertical caudad to cephalad incision in the extended neck position. However, the guidelines do not advise the incision commencement point. We sought to determine the minimum incision length and commencement point above the suprasternal notch required to ensure that the cricothyroid membrane would be accessible within its margins. METHODS: We measured using ultrasound, in 80 subjects (40 males and 40 females) without airway pathology, the distance between the suprasternal notch and the cricothyroid membrane, in the neutral and extended neck positions. We assessed the inclusion of the cricothyroid membrane within theoretical incisions of 0-100 mm in length made at 10 mm intervals above the suprasternal notch. RESULTS: In the 80 subjects, the distance ranged from 27 to 105 mm. Movement of the cricothyroid membrane on transition from the neutral to extended neck position varied from 15 mm caudad to 27 mm cephalad. The minimum incision required in the extended position was 70 mm in males and 80 mm in females, commencing 30 mm above the suprasternal notch. CONCLUSIONS: An 80 mm incision commencing 30 mm above the suprasternal notch would include all cricothyroid membrane locations in the extended position in patients without airway pathology, which is in keeping with the Difficult Airway Society guidelines recommended incision length.

Correlations of ADHD symptoms with neurometabolites measured by 1H magnetic resonance spectroscopy.

OBJECTIVES: Despite the number of studies on neurometabolite changes in ADHD (Attention deficit/hyperactivity disorder), there is lack of evidence on neurometabolite associations with ADHD symptoms. BACKGROUND: We aimed to find the correlations of neurometabolites with ADHD symptoms. METHODS: Twenty ADHD children were examined by means of 1H-MRS. The spectra were taken from dorsolateral prefrontal cortex (DLPFC) and white matter behind DLPFC, bilaterally. Neurometabolites were correlated with ADHD-RS-IV (ADHD-Rating Scales IV), CPRS (Conners Parent rating Scale) and DPREMB (Daily Parent Rating of Evening and Morning Behavior) scores. RESULTS: NAA/Cr (N-acetylaspartate/creatine) in the right DLPFC positively correlated with CPRS subscale IV learning problems and negatively correlated in the left white matter with DPREMB morning behavior subscale and ADHD-RS-IV score. Glx/Cr (glutamate + glutamine/creatine) positively correlated in the right white matter with ADHD-RS-IV and negatively correlated in the left white matter with DPREMB morning behavior subscale score. Cho/Cr (choline/creatine) in the left white matter negatively correlated with DPREMB morning behavior subscale and ADHD-RS-IV score. CONCLUSION: ADHD symptoms could result from different activities of the left- and right-hemisphere prefrontal circuits. In consequence to impulses to novel task searching the increased right prefrontal circuit activity could be mediated by different motivational control (Fig. 9, Ref. 73).

Theoretical optimal cricothyroidotomy incision length in female subjects, following identification of the cricothyroid membrane by digital palpation.

BACKGROUND: Misidentification of the cricothyroid membrane is frequent in females, placing them at risk of difficult or failed cricothyroidotomy in the event of failed oxygenation. If anatomy is impalpable, the current guidelines of the Difficult Airway Society, based on expert opinion, recommend an 8-10 cm vertical incision to facilitate access to the cricothyroid membrane. At present no evidence-based guideline exists regarding optimum site or length. We investigated the likelihood of inclusion of the cricothyroid membrane, within hypothetical vertical midline incisions, in a female population. METHODS: We asked clinicians to identify the cricothyroid membrane in both the neutral and extended head positions using palpation, the point identified acting as the theoretical midpoint of a cricothyroidotomy incision. We then identified the cricothyroid membrane using ultrasound. We determined the minimum incision length that would be required to ensure that the cricothyroid membrane lay within its boundaries, if clinician digital palpation was the method of cricothyroid membrane localisation. RESULTS: Ninety female subjects were recruited. Theoretical incisions of 7 and 8 cm were required for successful cricothyroidotomy in the neutral and extended head positions respectively. This was necessary because of the high failure rate of cricothyroid membrane identification (80.9%) and the wide range of error (7.2 cm in a vertical plane). CONCLUSIONS: Based on clinical estimation of the location of the cricothyroid membrane, an incision length of 8 cm, using the clinician's best estimate as its midpoint, would overlie all cricothyroid membrane locations. Our data support the current Difficult Airway Society guidelines for cricothyroidotomy incision length.

Preferences of Jehovah's Witnesses regarding haematological supports in an obstetric setting: experience of a single university teaching hospital.

BACKGROUND: Jehovah's Witnesses have been shown to be at increased risk of mortality and morbidity as a consequence of obstetric haemorrhage and refusal of blood products. Since 2004, however, Jehovah's Witnesses have been allowed to accept minor fractions of blood at their own discretion. We sought to determine the preferences of pregnant Jehovah's Witnesses regarding haematological supports since this policy change. METHODS: This is a retrospective observational study of consecutive Jehovah's Witnesses attending a university-affiliated tertiary referral centre between 1 January 2007 and 31 December 2013. The main outcome measure was the proportion of women who would be willing to accept blood products and other haematological supports in the event of life-threatening bleeding, should it occur. RESULTS: Seventy-six Jehovah's Witnesses attended for obstetric care during the study period. Major fractions of blood (red cells, plasma or platelets) were acceptable to 7.9% and 50% would accept some minor fractions. Some blood components were acceptable to 70.3% of nulliparous women compared to 48.9% of multiparous women. In women with advance directives some blood components were acceptable to 70.5% compared with 37.5% of those without. Recombinant factor VIIa was acceptable to 53.9%. Black African women had the lowest acceptance of any ethnic group of any blood products. CONCLUSION: The spectrum of acceptance of blood products is wide ranging within our obstetric Jehovah's Witnesses population. Recombinant factors are not universally acceptable despite their identification as non-blood products. A multidisciplinary approach with individualized consent is recommended.

Anaesthetic outcomes in obese parturients: the effect of assessment in the high-risk clinic.

BACKGROUND: Obese parturients are at high risk of complications during anaesthesia and early use of epidural analgesia in labour has been recommended for obese patients during labour. AIM: To assess the outcome of anaesthesia outpatient consultation for obese parturients. METHODS: We retrospectively compared outcomes of obese patients antenatally and an obese and non-obese control group over a 1-year period. Outcomes included potential airway problems, anaesthetic for caesarean section, use and success of epidural analgesia and cervical dilation at epidural placement. RESULTS: The proportion of obese patients who had predictable intubation difficulty was low (5%). Epidural use analgesia in labour (69 vs 36 vs 66%, P = 0.148) was similar between groups (obese, obese controls and non-obese controls, respectively). Cervical dilation at the time of epidural insertion in the obese group (2.0, 1.0-3.0 cm) was not different from obese controls (3.0, 1.75-5.75 cm). There was no difference in the number of attempts required to site the epidural between groups or the number of patients that required resiting of the epidural catheter. General anaesthesia was not required in any emergency case in this group. CONCLUSION: The outcomes of obese patients attending the anaesthetic clinic were mixed. Not all patients who were to advised have epidurals did so but those who did requested them in early labour and there was no requirement for general anaesthesia during emergency caesarean section and adverse airway events were avoided in this group.