C. W. Li

The clinical observation of difficult laryngoscopy and difficult intubation in infants with cleft lip and palate

Background:  The aims of this study were to evaluate the incidence of difficult laryngoscopy in infants with cleft lip and palate and to observe its relationships with age, sites, and degrees of deformities.

Glidescope®-assisted awake fibreoptic intubation : initial experience in 13 patients

reports: lessons from serotonin toxicity (serotonin syndrome). Anaesthesia 2006; 61: 419–22. 5 Gillman PK. A review of serotonin toxicity data: implications for the mechanisms of antidepressant drug action. Biological Psychiatry 2006; 59: 1046–51. 6 Wegener G, Volke V, Rosenberg R. Endogenous nitric oxide decreases hippocampal levels of serotonin and dopamine in vivo. British Journal of Pharmacology 2000; 130: 575–80. 7 Oxenkrug GF, Requintina PJ. Melatonin and jet lag syndrome. Experimental model and clinical implications. CNS Spectrums 2003; 8: 139–48. 8 Lerch S, Kupfer A, Idle JR, Lauterburg BH. Cerebral formation in situ of S-carboxymethylcysteine after ifosfamide administration to mice: a further clue to the mechanism of ifosfamide encephalopathy. Toxicology Letters 2006; 161: 188–94. 9 Lawrence KR, Adra M, Gillman PK. Serotonin toxicity associated with the use of linezolid: a review of postmarketing data. Clinical Infectious Diseases 2006; 42: 1578–83. 10 Gillman PK. Linezolid and serotonin toxicity. Clinical Infectious Diseases 2003; 37: 1274–5. 11 Gillman PK. Monoamine oxidase inhibitors, opioid analgesics and serotonin toxicity. British Journal of Anaesthesia 2005; 95: 434–41.

Assessment of small-dose fentanyl and sufentanil blunting the cardiovascular responses to laryngoscopy and intubation in children.

Background:  The authors found no study assessing the efficacy of small‐dose narcotics on the cardiovascular response from intubation in children, so they observed the effects of fentanyl 2 μg·kg−1 and sufentanil 0.2 μg·kg−1 on the cardiovascular changes during laryngoscopy and intubation in children.

The circulatory responses to fibreoptic intubation: a comparison of oral and nasal routes

The circulatory responses to fibreoptic intubation under general anaesthesia were studied in 60 adult female patients who were randomly assigned to receive either the oral or nasal route for insertion. Non‐invasive blood pressure and heart rate were recorded before anaesthesia induction (baseline values), immediately after anaesthesia induction (post‐induction values), at intubation and every minute for a further 5 min. The product of heart rate and systolic blood pressure (rate pressure product) at every time point was also calculated. The results showed that both fibreoptic orotracheal intubation and fibreoptic nasotracheal intubation resulted in significant increases in blood pressure, heart rate and rate pressure product compared to baseline and post‐induction values. The times required to reach the maximum values of systolic blood pressure and heart rate were significantly longer in the fibreoptic nasotracheal intubation group than in the fibreoptic orotracheal intubation group. There were no significant differences between the two groups in blood pressure, heart rate and rate pressure product at any measuring point, or in the maximum values during observation. The time required for recovery of systolic blood pressure to the post‐induction value was not significantly different between the two groups, but the time required for recovery of heart rate to post‐induction value was significantly longer in the fibreoptic orotracheal intubation group than in the fibreoptic nasotracheal intubation group. It was concluded that both fibreoptic orotracheal and fibreoptic nasotracheal intubations could cause a similar magnitude of circulatory responses in general anaesthetised, female adults, but the tachycardic response to fibreoptic orotracheal intubation lasted longer than that to fibreoptic nasotracheal intubation.

The effects of head flexion on airway seal, quality of ventilation and orogastric tube placement using the ProSeal™ laryngeal mask airway*

This prospective self‐controlled study was designed to evaluate the influences of head flexion on airway seal, quality of ventilation, and orogastric tube placement through the ProSeal™ laryngeal mask airway (ProSeal LMA™) in 80 anaesthetised, paralysed adult patients.

Blood pressure and heart rate changes during intubation: a comparison of direct laryngoscopy and a fibreoptic method.

Blood pressure and heart rate changes during nasotracheal intubation under general anaesthesia were studied in 100 patients who were randomly allocated to fibreoptic bronchoscope or direct laryngoscopy intubation. Noninvasive blood pressure and heart rate were recorded before and immediately after anaesthesia induction, at anaesthesia intubation and every minute thereafter for 5 min. Nasotracheal intubation was accompanied by significant increases in blood pressure and heart rate compared to baseline values in both groups. Blood pressure and heart rate at intubation, and the maximum values of blood pressure during the observation were significantly higher in the fibreoptic bronchoscope group. However, the maximum values of heart rate were not significantly different between the two groups. Fibreoptic nasotracheal intubation may result in more severe pressor and tachycardiac responses than direct laryngoscopic nasotracheal intubation.

Different small-dose remifentanil blunting the cardiovascular response to laryngoscopy and intubation in children: a randomized double-blind comparison.

Background: The available data provide inconsistent results on the efficacy of small‐dose remifentanil attenuating the cardiovascular response to intubation in children. Therefore, this randomized double‐blind study was designed to assess the ability of different small doses of remifentanil on the cardiovascular intubation response in children, with the aim of determining the optimal dose of remifentanil for this purpose. Methods: One hundred and twenty‐four children aged 3‐9 yr were randomized to one of four groups to receive the following in a double‐blind manner: normal saline (Group 1), remifentanil 0.75 &mgr;g kg−1 (Group 2), remifentanil 1 &mgr;g kg−1 (Group 3) and remifentanil 1.25 &mgr;g kg−1 (Group 4). Non‐invasive blood pressure and heart rate were recorded before anaesthesia induction (baseline value), immediately before intubation (postinduction values), at intubation and at 1 min intervals for 5 min after intubation. Results: Tracheal intubation caused significant increases in systolic blood pressure and heart rate in Groups 1‐3 compared with the baseline values. The maximum percent increases of systolic blood pressure and heart rate were 10% and 26% of the baseline values, respectively, in Group 2; 5% and 14% in Group 3; and 1% and 8% in Group 4 compared with 27% and 37% in Group 1. Except for the Group 3 vs. Group 4 comparison, there were significant differences among the four groups in the maximum percent increases of systolic blood pressure and heart rate. Conclusions: When used as part of anaesthesia induction with propofol and vecuronium in children, bolus administration of remifentanil resulted in a dose‐related attenuation of the cardiovascular intubation response.

The circulatory responses to tracheal intubation in children: a comparison of the oral and nasal routes

The circulatory responses to laryngoscopic tracheal intubation in 62 healthy children undergoing surgery requiring tracheal intubation were studied. They were randomly assigned to receive either the oral or nasal route for intubation. Baseline non‐invasive blood pressure and heart rate were recorded following induction of anaesthesia, at intubation and then every minute for 5 min. The percentage changes of systolic blood pressure and heart rate during the measurement period were calculated. The results demonstrated that intubation time was significantly longer in the nasal group. Both oral and nasal intubation caused significant increases in blood pressure and heart rate compared to baseline and postinduction values. However, there were no significant differences found between the two groups in relation to blood pressure and heart rate. The two groups were similar with respect to the percentage changes of systolic blood pressure and heart rate during the observation period. It is concluded that oral and nasal intubation using a direct laryngoscopy can result in a similar circulatory response in anaesthetised children.

A comparative study of hemodynamic responses to orotracheal intubation with fiberoptic bronchoscope and laryngoscope in children

Background : The purposes of this study were to further identify the hemodynamic responses to orotracheal intubation in children, using a fiberoptic bronchoscope (FOB) and a direct laryngoscope (DLS), and to validate whether the FOB can attenuate the hemodynamic response to orotracheal intubation compared with the DLS.

Blood pressure and heart rate changes during fibreoptic orotracheal intubation: a comparison of children and adults

Background and objectives: Autonomic circulatory regulation and airway anatomy in children are significantly different from those in adults. There is no available published data to compare whether there is a clinically relevant difference in the haemodynamic responses to fibreoptic orotracheal intubation (FOI) under the same conditions between children and adults. In this randomized clinical study, we compared the blood pressure (BP) and heart rate (HR) changes during FOI in 40 children aged 3.5–9 yr and 40 adults aged 21–57 yr, ASA 1 scheduled for elective plastic surgery under general anaesthesia requiring orotracheal intubation. Methods: Anaesthesia was induced with intravenous (i.v.) injection of fentanyl and propofol, and face mask inhalation of isoflurane before FOI. Noninvasive BP and HR were recorded before induction (baseline values), after induction (postinduction values), at intubation and for 5 min after intubation at 1‐min intervals. The percentage changes of BP and HR at each time point were calculated. Results: In children and adults, HR at intubation and 1–3 min after intubation were significantly higher than baseline and postinduction values. In adults, BP at intubation increased significantly compared to the postinduction values but did not exceed baseline values. In children, BP at intubation and 1 min after intubation were significantly higher than postinduction and baseline values. As compared to adults, FOI caused a more significant pressor response in children. The percentage changes of BP at intubation and 1 min after intubation were larger in children than in adults. However, there was no significant difference in the percentage change of HR during the observation between children and adults. Conclusions: Under general anaesthesia, FOI might cause a more significant pressor response in children than in adults.