Comparison of Flexiblade and Macintosh laryngoscopes: cervical extension angles during orotracheal intubation.

SUMMARY: The Flexiblade(TM) is a new laryngoscope with a flexible blade, a handle and a lever, allowing gradual flexion over the distal half of the blade. In this study, we aimed to compare cervical vertebral movements during tracheal intubation with the Flexiblade and Macintosh laryngoscope in 32 patients undergoing elective surgery requiring general anaesthesia (n = 16 per group). Fluoroscopic images of cervical movement were captured before, during and after intubation and evaluated by a radiologist. C1-C2 cervical vertebral movement was significantly reduced during the intubation in the Flexiblade group (p < 0.0001). C2-C3 cervical movement was similar in both groups (p = 0.81). No significant differences were noted in success rates for intubation, oxygen saturation levels, haemodynamic variables or intubation-related injury. The decreased extension angle between C1-C2 during Flexiblade laryngoscopy compared with Macintosh laryngoscopy may be an advantage where neurological damage with cervical movement is a concern.

Comparison of two ketamine-propofol dosing regimens for sedation during interventional radiology procedures.

AIM: Invasive diagnostic and therapeutic interventional radiological procedures can be painful and anxiety provoking. The combination of propofol and ketamine may minimize the need for supplemental opioid analgesics and has the potential to provide better sedation with less toxicity than either drug alone. METHODS: Seventy-two consenting ASA physical status I- III patients undergoing interventional radiological procedures under sedation were recruited according to a randomized, double-blind, institutional review board-approved protocol. Patients were randomized to two groups. Group 1 received propofol 0.5 mg.kg-1 + ketamine 0.5 mg.kg-1, and group 2 received propofol 0.5 mg.kg-1 + ketamine 0.25 mg.kg-1 intravenously. RESULTS: There were no significant differences between the two groups with respect to demographic characteristics and the duration of the interventional radiological procedure, hemodynamic data, oxygen saturation, or side-effects. However, the mean propofol dosage was higher in group 2 (33.7+/-39.3 mg) than in group 1 (15.5+/-22.3 mg), and the number of oversedated patients (sedation score >4) was higher in group 2 (19 patients) than group 1 (6 patients) (P=0.019 and P=0.001, respectively). Sixteen patients (44%) in group 1 and 21 (58%) patients in group 2 required additional propofol during the procedure. The mean recovery times were 12.1+/-1 minutes in group 1 and 13.8+/-0.8 minutes in group 2 (P>0.05). CONCLUSION: In conclusion, the two different dosages of ketamine coadministered with propofol for sedation during interventional radiological procedures showed no clinically significant hemodynamic changes or side effects, and both appeared to prompt early recovery time. We recommend propofol 0.5 mg.kg-1 + ketamine 0.5 mg.kg-1 for sedation and analgesia during interventional radiological procedures, rather than propofol 0.5 mg.kg-1 + ketamine 0.25 mg.kg-1 because the former combination is associated with reduced rescue propofol requirements and therefore less oversedation.

Bleeding pulmonary artery pseudoaneurysm secondary to squamous cell lung cancer: computed tomography findings and endovascular management.

A case of bleeding pulmonary artery pseudoaneurysm secondary to squamous cell lung cancer is reported. The patient presented with massive hemoptysis, diagnosis was made with multidetector computed tomography, and the pseudoaneurysm was successfully embolized with platinum coils. Hemoptysis ceased following the procedure.

Focal increased cortical density in immediate postembolization CT scans of patients with intracranial aneurysms.

BACKGROUND AND PURPOSE: Cortical hyperdensity was observed in the immediate postembolization CT scans of some patients with intracranial aneurysms following uneventful endovascular treatments. The clinical significance and possible underlying mechanism were evaluated. MATERIAL AND METHODS: Ninety-three consecutive patients with a total of 100 intracranial aneurysms, treated by endosaccular packing, were studied. Seventy-four aneurysms were treated with balloon assistance, and the remaining aneurysms were treated without balloon assistance. All patients underwent cranial CT just before and immediately after the endovascular treatment. If the post-treatment CT showed any new finding, an immediate MR imaging and a repeat CT 4-6 hours after the initial posttreatment CT were performed. Several parameters were investigated related to the presence of cortical hyperdensity. RESULTS: Cranial CT showed focal cortical hyperdensity following the treatment of 40/74 aneurysms (54%) with balloon remodeling and 9/26 aneurysms (34.6%) without balloon assistance. None of these patients were symptomatic, and cortical hyperdensity resolved in the repeat CT scans. A statistically significant relationship was observed between the presence of this finding and the total amount of contrast material, microcatheter time, number of balloon inflations, and total balloon inflation time. CONCLUSION: Immediate postembolization CT may show focal cortical hyperdensity following uneventful endovascular aneurysm treatment, most likely caused by blood-brain barrier disruption resulting in accumulation of contrast medium. The hyperdensity was more frequent when balloon assistance was used but was also seen in the patients with no balloon use. It is important to differentiate this clinically insignificant finding from possible hemorrhage, which would affect patients' immediate postprocedural medical management.

A contribution to the controversy over dimethyl sulfoxide toxicity: anesthesia monitoring results in patients treated with Onyx embolization for intracranial aneurysms.

Onyx injection is a new technique for embolization of cerebral aneurysms that is involved in a controversy about the 'toxicity' of its solvent, dimethyl sulfoxide (DMSO). We retrospectively studied 38 patients treated for aneurysms with the liquid polymer, Onyx. Induction was with propofol, fentanyl and vecuronium, and anesthesia was maintained with isoflurane in O2 and N2O. The patients were given 500 ml of fluid after induction, and bradycardia was prevented in order to keep patients hyperdynamic. Electrocardiography (ECG), non-invasive blood pressure (NIBP), pulse oximetry, core temperatures, invasive blood pressure (BP), etCO2, and urine output were monitored throughout the intervention. Heart rate and BP changes in response to balloon inflation, DMSO injection, Onyx injection and balloon deflation were recorded. The patients were followed with serial neurological examinations, computerized tomography and/or magnetic resonance imaging postoperatively for evidence of any neurological injury. Cumulative DMSO doses were always well under previously implicated doses for systemic toxicity. No changes implicating toxic reactions were observed during DMSO and Onyx injections. Balloon-induced changes returned to baseline within 1 min of balloon deflation. Technique-related permanent morbidity occurred in two patients (worsening of cranial nerve palsies in one and monocular blindness in another) and intracranial hemorrhage with resulting death in one patient. All patients showed a tendency to oxygen desaturation, but this finding did not cause any clinical consequence. Anesthesiologists need to be vigilant in monitoring patients treated with techniques that are new or are being developed. We have seen no evidence of toxicity or any anesthetic complications in our group of patients, our only clinical concern being a tendency to oxygen desaturation, which may be explained by the inhalational elimination of DMSO.

Use of sevoflurane during cardiopulmonary bypass decreases incidence of awareness.

BACKGROUND AND OBJECTIVE: The role of sevoflurane has not been studied in relation to awareness during anaesthesia. We observed the effect of sevoflurane on the incidence of awareness during cardiopulmonary bypass for open-heart surgery. METHODS: Fifty-nine patients of age >17 yr undergoing open-heart surgery with cardiopulmonary bypass were randomly assigned to two groups. In both groups, induction was with etomidate, dehydrobenzperidol and fentanyl; anaesthesia was maintained with sevoflurane, fentanyl and N20; vecuronium was used for muscular paralysis. Group 1 (30 patients) received dehydrobenzperidol and fentanyl during cardiopulmonary bypass; Group 2 (29 patients) received sevoflurane and fentanyl. Patients were given different auditory inputs during different phases of surgery. All patients were interviewed with standard questions 8 and 24 h postoperatively for evidence of explicit awareness. RESULTS: Five patients in the dehydrobenzperidol group gave a history of awareness (16.67%) as opposed to none in the sevoflurane group. The difference in the incidences of awareness was significant (P < 0.05), but no differences were found between the interviews conducted at 8 and 24 h. Sevoflurane and opioid combination reduced the incidence of awareness in open-heart surgery.