This systematic review included controlled clinical trials comparing tracheal intubation (TI) with alternative airway techniques (AAT) (bag-mask ventilation and use of extraglottic devices) performed by paramedics in the prehospital setting. A priori outcomes to be assessed were survival, neurologic outcome, airway management success rates and complications. We identified trials using EMBASE, MEDLINE, CINAHL, The Cochrane Library, Web of Science, author contacts and hand searching. We included 5 trials enrolling a total of 1559 patients. No individual study showed any statistical difference in outcomes between the TI and AAT groups. Because of study heterogeneity, we did not pool the data. This is the most comprehensive review to date on paramedic trials. Owing to the heterogeneity of prehospital systems, administrators of each system must individually consider their airway management protocols.

A 45-year-old male, with symptoms of many years standing of gastro-oesophageal reflux disease, was subjected, under general anaesthesia, to laparoscopic fundoplication.Tracheal intubation yielded no problems but great difficulties were encountered during tube insertion into the oesophagus. After surgery, aphonia developed. Laryngological examination demonstrated paralysis of the left vocal cord. Voice strength returned to the pre-operative status after 3 months, and laryngological examination confirmed normal mobility of both cords. The possible cause of the complication was damage to the left recurrent laryngeal nerve which occurred during insertion of the tube into the oesophagus. Gastro-oesophageal reflux disease causing ‘acid laryngitis’ can create conditions favouring this type of complication.

The aim of this study was to compare the effect of three different induction techniques, with or without neuromuscular block, on tracheal intubation, haemodynamic responses and cardiac rhythm. Ninety children, aged 1–3 years, undergoing day-case adenoidectomy were randomly allocated to three groups: group TS received thiopentone 5 mg kg−1 and suxamethonium 1.5 mg kg−1, group H 5 Vol.% halothane and group PA alfentanil 10 μg kg−1 and propofol 3 mg kg−1 for induction of anaesthesia. No anticholinergics were used. Holter-monitoring of the heart rate and rhythm was started at least 15 min before induction of anaesthesia and continued until 3 min after intubation. Tracheal intubation was performed by an anaesthetist blinded to the induction method and judged as excellent, moderate or poor according to ease of laryngoscopy, position of vocal cords and incidence of coughing after intubation. Tracheal intubation was successful at the first attempt in all children in groups TS and H and but only in 80% in group PA (P=0.001). Intubating conditions were excellent in 22 (73%), 22 (73%) and one (3%) of the patients in groups TS, H and PA, respectively (P=0.001). Cardiac dysrhythmias (supraventricular extrasystole or junctional rhythm) occurred in two (7%) patients in groups PA and H each (NS). Bradycardia occurred in 0 (0%), four (14%) and six (21%) children in groups TS, H and PA, respectively (P=0.007 PA vs.TS, P=0.03 H vs. TS). In conclusion, induction of anaesthesia with propofol 3 mg kg−1 and alfentanil 10 μg kg−1 without neuromuscular block did not provide acceptable intubating conditions in children 1–3 years, although it preserved arterial pressure better than thiopentone/suxamethonium or halothane. Cardiac dysrhythmias were few regardless of the induction method.

A study was conducted on 100 middle-aged to elderly patients (n=52, healthy; n=48, suffering from either diabetes, hypertension, ischaemic heart disease or combination of these diseases) undergoing cataract extraction to assess the effects of laryngoscopy and tracheal intubation, anaesthesia and surgery, eye bandaging and tracheal extubation, saline (control), magnesium sulphate 40 mg kg−1, esmolol 4.0 mg kg−1, lignocaine 1.5 mg kg−1 and glyceryl trinitrate 7.5 μg kg−1 given i.v. at induction of anaesthesia on heart rate (HR), blood pressure (BP), rate-pressure product (RPP) and pressure-rate quotient (PRQ). Anaesthesia was standardized. Haemodynamic responses and requirements for atropine, ephedrine and labetalol to maintain HR and BP during surgery were similar inhealthy and diseased patients, and in the test drug groups. Differences produced by the test drugs were evident until 5 min following intubation. Esmolol prevented rises in HR and RPP. Glyceryl trinitrate prevented a rise in BP, but was associated with tachycardia and a fall in PRQ to < 1.0. Magnesium sulphate and lignocaine did not prevent responses to laryngoscopy and tracheal intubation, and were associated with rises in RPP. Application of the eye dressing and tracheal extubation at the end of surgery each caused significant increases in HR, BP and RPP in all groups.

A double-blind and randomized study design was used to investigate 100 healthy children, aged 1–5 years. Intubating conditions and cardiovascular changes duraning deep halothane anaesthesia, defined as an endtidal concentration of 2%, were compared with those changes during 1% halothane and suxamethonium relaxation. Intubating conditions were graded according to the ease of laryngoscopy, vocal cord position, coughing and jaw relaxation. In each group 96% of the children demonstrated acceptable intubating conditions. Jaw relaxation was worse in the 1% halothane/-suxamethonium group (P < 0.01). When anaesthesia with 2% or 1% halothane was compared there was a more pronounced decrease in systolic blood pressure (18 vs. 8%, (P < 0.001). Junctional rhythm occured more frequently during deep halothane anaesthesia (46 vs.18%, (P < 0.01). Intravenously (i.v.) administered atropine attenuated blood pressure depression significantly and reinstituted sinus rhythm in most cases.