Oxygen saturation and cardiovascular changes during fibreoptic intubation under general anaesthesia

Sixty patients who required fibreoptic nasotracheal intubation were studied. Arterial oxygen saturation, arterial blood pressure and heart rate were monitored continuously during fibreoptic intubation under deep halothane anaesthesia. There were significant decreases (p less than 0.001) in arterial blood pressure and heart rate despite administration of intravenous colloid and atropine. Almost one third of the patients (18 out of 60) suffered a decrease in arterial oxygen saturation below 90% during the intubation sequence and in five patients the saturation fell below 80%. The episodes of desaturation were not related to the induction-intubation time or to the grade of laryngeal visibility at direct laryngoscopy.     

Randomized, controlled trial of the double setup tracheal tube during fibreoptic orotracheal intubation under general anaesthesia

Background. Impingement of the tracheal tube (ETT) on upperairway structures during railroading over the fibreoptic bronchoscope(FOB) occurs commonly. Potential complications of impingementinclude prolonged intubation time, leading to arterial desaturation,failed intubation and laryngeal trauma. The objective of thisrandomized, controlled trial was to assess the effect of thedouble setup ETT (a paediatric ETT is placed inside an adultETT) on the incidence of impingement during orotracheal fibreopticintubation. Method. Two hundred patients were randomized to have a singleETT or double setup ETT. After induction of anaesthesia, fibreopticorotracheal intubation was performed. The degree of impingementof the ETT during advancement over the FOB was assessed usinga standardized scoring system based on the manoeuvres requiredto overcome the impingement. Results. The incidence of impingement was lower using the doublesetup ETT compared with the single ETT (18 vs 93%, P<0.001).The double setup ETT also reduced the incidence of impingementrequiring more than a simple 90° counterclockwise rotationto achieve intubation (3 vs 14%, P=0.01) and reduced the medianintubation time (31 vs 35 s, P=0.046). Conclusions. The double setup ETT is effective in reducing ETTimpingement and in reducing intubation time. We did not findan association between ETT impingement and arterial desaturation. Br J Anaesth 2004; 92: 536–40     

Orotracheal fibreoptic intubation in children under general anaesthesia

Orotracheal fibreoptic intubation under general anaesthesia in children was studied in eleven consecutive patients of three months to eight-years-of-age without anticipated intubation difficulties. One case report is also included. Three fibrescopes with a different diameter were used in the study. The fibrescope used was chosen so that it fitted snugly in the tracheal tube. The fibreoscopy was prolonged in one patient due to mucus and two tries were needed. Resistance to the tracheal tube upon intubation was encountered in five patients, only one of these patients was older than two years. Fibreoptic intubation succeeded in nine patients. Two patients were intubated with the Macintosh laryngoscope. The problems encountered in children during orotracheal fibreoptic intubation under general anaesthesia are the same as with adults: easy fibreoscopy is not always followed by easy tracheal intubation, there may be prolonged fibreoscopy and failed intubations. Manipulation of the tracheal tube can lead to successful tracheal intubation and resistance to the tube is more common in smaller children.     

Blood pressure response of neonates to tracheal intubation

Blood pressure and pulse rate responses to tracheal intubation were studied by oscillotonometric technique in 45 term neonates and 15 infants of similar postconceptual age. No hypertensive response was found in neonates intubated awake and pressures did not differ from those of babies intubated under halothane or after thiopentone and muscle relaxant. The infants did however show a significant increase in systolic and diastolic pressures which indicates that this response may develop after the first month of life.     

Effect of fentanyl on the circulatory responses to orotracheal fibreoptic intubation

The effectiveness of fentanyl in attenuating the pressor and heart rate response to orotracheal fibreoptic intubation under general anaesthesia was assessed in 60 healthy patients undergoing elective surgery. Patients were randomly assigned to receive either fibreoptic intubation with or without fentanyl 6 micrograms.kg-1 or traditional Macintosh intubation with fentanyl 6 micrograms.kg-1. A standardised general anaesthetic was administered which included temazepam premedication, thiopentone, atracurium, oxygen, nitrous oxide and isoflurane. The pressor response to fibreoptic intubation was suppressed in those patients who received fentanyl and was similar to that seen in the Macintosh-fentanyl group of patients. The heart rate response to fibreoptic intubation was also significantly reduced in the patients who received fentanyl, but, in contrast, was still significantly greater than that in the Macintosh-fentanyl group. Fentanyl 6 micrograms.kg-1 appears to have a useful place in attenuating the cardiovascular effects of fibreoptic intubation under general anaesthesia.     

A comparison of the intubating laryngeal mask tracheal tube with a standard tracheal tube for fibreoptic intubation

We conducted a prospective randomised study to compare the intubating laryngeal mask tracheal tube with a standard tube, for ease of tracheal intubation over a fibrescope. Thirty-six patients were investigated, using a sequential analysis technique. Ease of intubation was improved when the intubating laryngeal mask tracheal tube was used compared with the standard tube (p = 0.0009). Median (interquartile range [range]) intubation times (time from the tube's tip being level with the patient's teeth to successful placement) were 1.5 (1-2.3 [1-3]) s when the intubating laryngeal mask tracheal tube was used and 5 (3-7.3 [3-13]) s when the standard tube was used (p < 0.0001).     

Awake fibreoptic intubation for a rare cause of upper airway obstruction-an infected laryngocoele

The anaesthetic management of a patient with an infected laryngocoele is presented. The relevance of this condition to the anaesthetist is discussed.     

Facial fractures and submental tracheal intubation

Submental tracheal intubation is a simple, quick and effective alternative to oral and nasal tracheal intubation or tracheostomy in the surgical management of selected patients with craniomaxillofacial injuries. It has a low morbidity and it does not impede the surgical field, allowing for temporary maxillo-mandibular fixation (jaw wiring) intra-operatively, and nasal assessment, manipulation and bone grafting, either simultaneously or as an independent procedure. We report 12 cases utilizing this technique in this retrospective study, this includes 11 patients with mid-facial fractures and associated base of skull fractures, and one patient who underwent an elective Le Fort III advancement. The techniques and indications for submental tracheal intubation are described.     

Complete airway obstruction during awake fibreoptic intubation

Awake fibreoptic intubation is well established as the optimum method of securing the airway in patients in whom difficulty is anticipated. We report a patient undergoing awake fibreoptic intubation in whom the use of topical local anaesthetic precipitated acute loss of the airway so that urgent surgical intervention was required.