Tracheal intubation in morbidly obese patients: a comparison of the Intubating Laryngeal Mask Airway™ and Laryngeal Mask Airway CTrach™.

The aim of this study was to evaluate the efficacy of the Intubating Laryngeal Mask Airway™ (ILMA) and Laryngeal Mask Airway CTrach™ (LMA CTrach) in facilitating tracheal intubation in morbidly obese patients. Eighty patients (body mass index >40 kg x m(-2)) were randomly allocated to the ILMA or the LMA CTrach. The median (IQR [range]) total time taken for tracheal intubation was shorter with the ILMA than with the LMA CTrach (78 (63-105 [40-265]) s vs 128 (98-221 [60-423]) s, respectively; p<0.001). Significantly more manoeuvres were applied for the satisfactory ventilation and viewing of the glottis with the LMA CTrach (25% vs 55% with the ILMA; p=0.006). During the postoperative period, there was more sore throat with the LMA CTrach (p<0.02). We conclude that the ILMA results in shorter intubation times with fewer manoeuvres and sore throat compared with the LMA CTrach in the morbidly obese.

Prediction of difficult tracheal intubation in Turkish patients: a multi-center methodological study.

BACKGROUND AND OBJECTIVE: Preoperative evaluation is important in the detection of patients at risk for difficult airway management. It is still unclear whether true prediction is possible and which variables should be chosen for evaluation. The aim of this prospective, multi-centre study was to investigate the incidence of difficult intubation, the sensitivity and positive predictive values of clinical screening tests and whether combining two or more of these tests will improve the prediction of difficult intubation in Turkish patients. METHODS: Seven study sites from six regions in Turkey participated in this study. One thousand six hundred and seventy-four ASA physical status I-III patients, scheduled to undergo elective surgery under general anaesthesia, were included. RESULTS: The incidence of difficult intubation was 4.8% and increased with age (P < 0.05). The incidence of difficult intubation was significantly higher in patients who had a Mallampati III or IV score, a decreased average thyromental and sternomental distance, decreased mouth opening, or decreased protrusion of the mandible (P < 0.05). Mouth opening and Mallampati III-IV were found to be the most sensitive criteria when used alone (43% and 35%, respectively). Combination of tests did not improve these results. CONCLUSIONS: There is still no individual test or a combination of tests that predict difficult intubations accurately. Tests with higher specificity despite low positive predictive value are needed.

Comparison of laryngeal tube with laryngeal mask airway in anaesthetized and paralysed patients.

BACKGROUND AND OBJECTIVE: The laryngeal mask has become a widely accepted alternative to endotracheal intubation and mask ventilation. The laryngeal tube is a relatively new supraglottic airway device for airway management. We compared the new version of the laryngeal tube with the laryngeal mask. METHODS: In a randomized design, either a laryngeal tube (n = 66) or a laryngeal mask (n = 66) were inserted. Ease of insertion, oxygenation and ventilation, spirometry data and postoperative airway morbidity were determined. RESULTS: After successful insertion, it was possible to maintain oxygenation and ventilation in all the patients. Insertion success rates after the first, second and third attempts were 84.8% (n = 56), 12.1% (n = 8) and 3% (n = 2) for the laryngeal tube compared with 56.1% (n = 37), 25.8% (n = 17) and 18.2% (n = 12) for the laryngeal mask (P = 0.001). There was no significant difference in peak airway pressure, and dynamic compliance between the groups (P > 0.05). Blood on the cuff after removal of the device was noted in one patient with the laryngeal tube and in 10 patients with the laryngeal mask. Six patients in the laryngeal mask group complained of hoarseness (P = 0.012). CONCLUSION: With respect to clinical function, the new version of the laryngeal tube and the laryngeal mask are similar and either device can be used to establish a safe and effective airway in paralysed patients.

Clonidine addition prolongs the duration of caudal analgesia.

BACKGROUND: In this study, using a dose-ranging design, we examined the effects of clonidine with 0.125% bupivacaine on the duration of post-operative analgesia in caudal anaesthesia in children. METHODS: We conducted a controlled, prospective study of clonidine in caudal anaesthesia in 60 children, aged 1-10 years, undergoing elective inguinal hernia repair. Induction and maintenance of anaesthesia were performed by inhalation of sevoflurane and nitrous oxide. The children were randomized in a double-blind fashion to four groups, and were given a caudal anaesthetic with either 0.125% plain isobaric bupivacaine (1 ml/kg) or bupivacaine plus 1, 1.5 or 2 microg/kg of clonidine. The blood pressure and heart rate were recorded peri-operatively. Analgesia was evaluated by the modified Children's Hospital of Eastern Ontario Pain Scale (mCHEOPS) or a visual analogue scale (VAS). Paracetamol was given when the mCHEOPS score was greater than five or when the VAS score was greater than 30 mm. The monitoring of scores for pain, haemodynamic changes and post-operative nausea and vomiting was performed by nurses blind to the study allocation. RESULTS: The duration of analgesia was found to be significantly longer in the group given bupivacaine plus 2 microg/kg of clonidine (median, 650 min; range, 300-900 min). Peri-operative hypotension and bradycardia, post-operative respiratory depression and motor block were not recorded in any patient. CONCLUSIONS: The addition of clonidine to 0.125% bupivacaine prolongs the duration of post-operative analgesia without any respiratory or haemodynamic side-effects.