Subglottic stenosis imitating the carina - a case report of airway mimicry.

We present a case of awake tracheal intubation with flexible bronchoscopy which resulted in incorrect tracheal tube placement. The presence of a stenotic subglottic lesion with an appearance similar to the carina led to the tube being positioned with only the tip within the trachea whilst the cuff was located between the vocal cords. A capnography trace was identified before induction of anaesthesia; however, visual confirmation of the carina was undertaken in a rushed manner due to the patient becoming agitated. Once the incorrect tracheal tube placement was identified, the decision was made to wake the patient. Thereafter, a more experienced operator successfully performed awake tracheal intubation with flexible bronchoscopy using a smaller tracheal tube, which easily passed through the subglottic stenosis. This report emphasises the importance of performing the 'two-point check' every time awake tracheal intubation is undertaken: to confirm correct tube placement, both a capnography trace and view of the tracheal lumen including the carina and main bronchi is required. This must be properly performed before induction of anaesthesia; safety should not be compromised by a stressful environment or time pressure.

Non-invasive haemoglobin measurement as an index test to detect pre-operative anaemia in elective surgery patients - a prospective study.

Non-invasive haemoglobin measurement using absolute values lacks the precision to be the sole basis for the treatment of pre-operative anaemia. However, it can possibly serve as a screening test, indexing 'anaemia' with high sensitivity when values remain under prespecified cut-off values. Based on previous data, non-invasive haemoglobin cut-off values (146 g.l-1 for women and 152 g.l-1 for men) detect true anaemia with 99% sensitivity. An index test with these prespecified cut-off values was verified by prospective measurement of non-invasive and invasive haemoglobin pre-operatively in elective surgical patients. In 809 patients, this showed an estimated sensitivity (95%CI) of 98.9% (94.1-99.9%) in women and 96.4% (91.0-99.0%) in men. This saved invasive blood tests in 9% of female and 28% of male patients. In female patients, a lower non-invasive haemoglobin cut-off value (138 g.l-1 ) would save 28% of invasive blood tests with a sensitivity of 95%. The target 99% sensitivity would be reached by non-invasive haemoglobin cut-off values of 152 g.l-1 in female and 162 g.l-1 in male patients, saving 3% and 9% of invasive blood tests, respectively. Bias and limits of agreement between non-invasive and laboratory haemoglobin levels were 2 and - 25 to 28 g.l-1 , respectively. Patient and measurement characteristics did not influence the agreement between non-invasive and laboratory haemoglobin levels. Although sensitivity was very high, the index test using prespecified cut-off values just failed to reach the target sensitivity to detect true anaemia. Nevertheless, with respect to blood-sparing effects, the use of the index test in men may be clinically useful, while an index test with a lower cut-off (132 g.l-1 ) could be more clinically appropriate in women.

Assessment of haemoglobin measurement by several methods - blood gas analyser, capillary and venous HemoCue® , non-invasive spectrophotometry and laboratory assay - in term and preterm infants.

A laboratory haematology analyser is the gold standard for measuring haemoglobin concentration but has disadvantages, especially in neonates. This study compared alternative blood-sparing and non-invasive methods of haemoglobin concentration measurement with the gold standard. Haemoglobin concentrations were measured using a laboratory haematology analyser (reference method), blood gas analyser, HemoCue® using venous and capillary blood samples and a newly developed non-invasive sensor for neonates < 3 kg. A total of 63 measurements were performed. Body weight (2190 (1820-2520 [967-4450]) g) and haemoglobin concentration (12.3 (10.6-15.2 [8.2-20.5]) g.dl-1 ) varied widely. Bias/limits of agreement between the alternative methods and reference method were -0.1/-1.2 to 1.0 g.dl-1 (blood gas analyser), -0.4/-1.8 to 1.1 g.dl-1 (HemoCue, venous blood), 0.7/-1.9 to 3.2 g.dl-1 (HemoCue, capillary blood) and -1.2/-4.3 to 2 g.dl-1 (non-invasive haemoglobin measurement). Perfusion index, body weight and fetal haemoglobin concentration did not affect the accuracy of the alternative measurement methods, and these were successfully applied in term and preterm infants. However, the accuracies of non-invasive haemoglobin measurement and HemoCue of capillary blood especially lacked sufficient agreement with that of the reference method to recommend these methods for clinical decision making.

A comparison of the Enk Fiberoptic Atomizer Set(™) with boluses of topical anaesthesia for awake fibreoptic intubation.

We compared the Enk Fiberoptic Atomizer Set(™) with boluses of topical anaesthesia administered via the working channel during awake fibreoptic tracheal intubation in 96 patients undergoing elective surgery. Patients who received topical anaesthesia via the atomiser, compared with boluses via the fibreoptic scope, reported a better median (IQR [range]) level of comfort: 1 (1-3 [1-10]) vs. 4 (2-6 [1-10]), p < 0.0001; experienced a reduced total number of coughs: 6 (3-10 [0-34]) vs. 11 (6-13 [0-25]), p = 0.0055; and fewer distinct coughing episodes: 7% vs. 27% respectively, p = 0.0133. The atomiser technique was quicker: 5 (3-6 [2-12]) min vs. 6 (5-7 [2-15]) min, p = 0.0009; and required less topical lidocaine: 100 mg (100-100 [80-160]) vs. 200 mg (200-200 [200-200]), p < 0.0001. Four weeks after nasal intubation, the incidence of nasal pain was less in the atomiser group compared with the control group (8% vs. 50%, p = 0.0015). We conclude that the atomiser was superior to bolus application for awake fibreoptic tracheal intubation.

[Indirect laryngoscopy/video laryngoscopy. A review of devices used in emergency and intensive care medicine in Germany]. / Indirekte Laryngoskopie/Videolaryngoskopie. Übersicht über in Deutschland verwendete Instrumente in der Notfall- und Intensivmedizin.

Airway management in intensive care or emergency medicine is particularly challenging and is often associated with life-threatening complications. An innovation in the field of airway management is the use of indirect laryngoscopy by means of video laryngoscopes. A digital camera or an optical system at the tip of a laryngoscope blade enables an indirect "look around the corner" to the glottis. Studies have shown that the advantages of video laryngoscopes for endotracheal intubation are particularly beneficial in difficult airway situations. However, the successful use in challenging intubations requires experience and regular use in daily practice. This review gives an overview of indirect laryngoscopes commonly used in Germany and also presents new study results for these novel devices.