Comparison of the Bullard and Macintosh laryngoscopes for endotracheal intubation of patients with a potential cervical spine injury

BACKGROUND

In the emergency trauma situation, in-line stabilization (ILS) of the cervical spine is used to reduce head and neck extension during laryngoscopy. The Bullard laryngoscope may result in less cervical spine movement than the Macintosh laryngoscope. The aim of this study was to compare cervical spine extension (measured radiographically) and time to intubation with the Bullard and Macintosh laryngoscopes during a simulated emergency with cervical spine precautions taken.

METHODS

Twenty-nine patients requiring general anesthesia and endotracheal intubation were studied. Patients were placed on a rigid board and anesthesia was induced. Laryngoscopy was performed on four occasions: with the Bullard and Macintosh laryngoscopes both with and without manual ILS. Cricoid pressure was applied with ILS. To determine cervical spine extension, radiographs were exposed before and during laryngoscopy. Times to intubation and grade view of the larynx were also compared.

RESULTS

Cervical spine extension (occiput-C5) was greatest with the Macintosh laryngoscope (25.9 degrees +/- 2.8 degrees). Extension was reduced when using the Macintosh laryngoscope with ILS (12.9 +/- 2.1 degrees) and the Bullard laryngoscope without stabilization (12.6 +/- 1.8 degrees; P < 0.05). Times to intubation were similar for the Macintosh laryngoscope with ILS (20.3 +/- 12.8 s) and for the Bullard without ILS (25.6 +/- 10.4 s). Manual ILS with the Bullard laryngoscope results in further reduction in cervical spine extension (5.6 +/- 1.5 degrees) but prolongs time to intubation (40.3 +/- 19.5 s; P < 0.05).

CONCLUSIONS

Cervical spine extension and time to intubation are similar for the Macintosh laryngoscope with ILS and the Bullard laryngoscope without ILS. However, time to intubation is significantly prolonged when the Bullard laryngoscope is used in a simulated emergency with cervical spine precautions taken. This suggests that the Bullard laryngoscope may be a useful adjunct to intubation of patients with potential cervical spine injury when time to intubation is not critical.

Ruptured spleen as a complication of insertion of an automatic implantable cardioverter-defibrillator

The authors describe a previously unreported complication of insertion of an automatic implantable cardioverter-defibrillator via the left subcostal surgical approach. Splenic hematoma, intraperitoneal hemorrhage and hypotension developed in a 66-year-old man within 5 days of implantation, and the patient underwent splenectomy.

Magnetic resonance imaging of a giant nonfunctioning retroperitoneal paraganglioma

The authors describe the magnetic resonance imaging (MRI), computed tomographic, ultrasonographic and angiographic appearance of a giant nonfunctioning retroperitoneal paraganglioma. To their knowledge, the MRI appearance of a nonfunctioning paraganglioma has not been previously described. The MRI characteristics of the nonfunctioning tumour were similar to those of a functioning paraganglioma and included hyperintensity in T2-weighted images and intense enhancement after intravenous administration of contrast agent.

Hepatic pseudomass observed with computed tomography after direct injection of contrast agent into the portal vein

Hepatic pseudomasses have been described on both non-contrast and contrast-enhanced computed tomography (CT) scans, as well as on scans obtained by CT-arteriography and CT-portography. The authors describe a hepatic pseudomass that appeared in CT scans after direct injection of contrast material into the portal vein through an indwelling catheter.

Dynamic abdominal computed tomography: "top-down" compared with "bottom-up" imaging

Dynamic contrast-enhanced computed tomography (CT) of the liver is usually performed from the top down, and there is usually less opacification of the top slices than the more inferior slices. The authors reasoned that reversing the direction of scanning would allow more time for the parenchyma at the top of the liver to become enhanced and would result in better opacification of the parenchyma and the hepatic veins. To test this hypothesis they assigned 32 patients to either a "top-down" or a "bottom-up" group; each patient then underwent unenhanced and contrast-enhanced CT. The method of intravenous administration of contrast agent was identical in the two groups and consisted of rapid injection of 135 mL of iohexol by a power injector; scanning was initiated 30 seconds after the injection was started. Attenuation measurements were obtained at specified areas in the liver and in the hepatic and portal veins. The degree of enhancement was calculated at each site and was compared between groups. The upper portion of the liver showed significantly greater enhancement in the bottom-up sequence than in the top-down sequence (123% and 22% respectively; p < 0.01); the entire liver showed excellent enhancement in the bottom-up sequence. In addition, the hepatic veins showed significantly greater conspicuity in the bottom-up sequence (p < 0.01). The authors conclude that the dynamic bottom-up method yields excellent hepatic enhancement and vascular opacification and is therefore superior to the standard top-down method.

Producing picture-perfect posters

Scientific posters form an integral part of many radiology meetings. They provide the opportunity for interested parties to read the material at an individualized pace, to study the images in detail, and to return to the exhibit numerous times. Although the content of the poster is undoubtedly its most important component, the visual presentation of the material can enhance or detract from the clarity of the message. With the wide availability of sophisticated computer programs for desktop publishing (DTP), one can now create the poster on a computer monitor with full control of the form as well as the content. This process will result in a professional-appearing poster, yet still allow the author the opportunity to make innumerable revisions, as the poster is visualized in detail on the computer monitor before printing. Furthermore, this process is less expensive than the traditional method of typesetting individual sections separately and mounting them on cardboard for display. The purpose of this article is to present our approach to poster production using commercially available DTP computer programs.

Sonolucent peripancreatic masses: differential diagnosis and related imaging

The most common cause of a sonolucent mass in the epigastrium is a pancreatic pseudocyst; however, several other conditions can simulate a pseudocyst on ultrasonography (US) scans. This pictorial essay illustrates the spectrum of conditions that may present in this fashion and demonstrates the use of other imaging modalities, such as colour-flow and pulsed Doppler US, computed tomography, magnetic resonance imaging and angiography, in their evaluation.

Peripancreatic fluid collections: vascular structures masquerading as pseudocysts

Five patients with splanchnic arterial aneurysms and one patient with a tortuous splenic vessel presented with peripancreatic masses that exhibited an anechoic portion in real-time ultrasonography (US) images; the masses were incorrectly diagnosed as pseudocysts. In two patients a vascular abnormality was suspected, and colour-flow Doppler and pulsed Doppler US were performed; these techniques showed the presence of pseudoaneurysms. In the other four patients the possibility of a pseudoaneurysm was not entertained until further studies had been performed. These results emphasize the need for colour-duplex US evaluation of all peripancreatic fluid collections during the initial US examination to avoid the misinterpretation of an aneurysm or a pseudoaneurysm as a simple or complex fluid collection and to prevent the potential disaster of performing biopsy, surgery or other interventions.

CT findings in patients with small-bowel transplants

Orthotopic small-bowel transplantation procedures are being performed increasingly often worldwide. CT plays an important role in both the preoperative assessment and the postoperative care of these patients. This pictorial essay serves to acquaint radiologists with the CT findings related to small-bowel transplantation.

Adenocarcinoma of the pancreatic ducts: comparative evaluation with CT and MR imaging at 1.5 T

A prospective comparison of computed tomography (CT) and magnetic resonance (MR) imaging at 1.5 T was performed in 50 patients with the suspected diagnosis of pancreatic carcinoma. CT scans were obtained before and after administration of contrast material in 41 of 50 patients (82%); 34 of 41 postcontrast scans (83%) were obtained with dynamic CT. MR images were interpreted without knowledge of the results of CT, ultrasound, cholangiography, or endoscopic retrograde cholangiopancreatography in 48 patients (96%). Surgical correlation of findings at CT and MR imaging was performed in 24 patients (48%) at laparotomy and in two patients (4%) at autopsy. On T1-weighted MR images, relatively diminished signal intensity of tumor compared with that of the adjacent pancreas was a consistent finding. MR imaging proved superior to CT in identification of pancreatic carcinoma (particularly in smaller intrapancreatic tumors), peripancreatic extension, vascular and portal vein invasion, and duodenal invasion. These results suggest that MR imaging of the pancreas is superior in many instances to CT in preoperative evaluation of pancreatic carcinoma.

Human orthotopic small intestine transplantation: radiologic assessment

The authors describe the postoperative anatomy and review the radiologic examinations of five patients who underwent orthotopic small intestine or combined orthotopic liver and small intestine transplantation. Mucosal thickening of the transplanted intestine was demonstrated on the first postoperative contrast material-enhanced images and was due to submucosal edema. This resolved within 2 weeks in the long-term survivors. Bowel peristalsis appeared normal as early as 31 days after transplantation. Contrast-enhanced examinations of the intestine were useful to exclude surgical complications such as anastomotic leaks or strictures, but were insensitive for biopsy-proved cytomegalovirus enteritis or rejection.

Telebrix: a better-tasting oral contrast agent for abdominal computed tomography

In a randomized, controlled, double-blind trial, Telebrix 38 (ioxithalamate) and Gastrografin (diatrizoate) were compared with respect to taste and degree of opacification of the alimentary canal when used in computed tomography of the abdomen and pelvis. Bowel opacification was excellent with both contrast agents. Patients rated the 2% solution of Telebrix in water significantly better in taste than the control contrast medium, a 2% solution of Gastrografin in water. Of the patients in the Telebrix group 89% judged the taste to be excellent or good, compared with 59% in the Gastrografin group (p = 0.012, Fisher's exact test). Only 1 of 28 patients in the Telebrix group was unwilling to drink Telebrix again, compared with 6 of 27 patients in the Gastrografin group (p = 0.045, Fisher's exact test). There were no significant side effects. Dilute Telebrix 38 is preferable to dilute Gastrografin, in terms of taste and patient tolerance, for bowel opacification on computed tomography, and produces equivalent, excellent bowel opacification.

Digital teleradiology: Seaforth--London network

A total digital teleradiology system using a prototype DuPont laser beam scanner (DTR 2000) and a Bell Canada digital transmission network was evaluated. A total of 489 radiographic and ultrasonographic examinations were transmitted for interpretation from a 41-bed rural community hospital in Seaforth to the University Hospital in London, Ontario, 80 km away. There was concurrence in 98% of these examinations, i.e. the laser-sensitive facsimile film clearly duplicated the original film findings and allowed a confident interpretation to be made. We conclude that this system could readily serve the needs of family physicians in rural communities for radiologic consultation, diagnosis, management, and triage of patients 24 hours per day.

Single-contrast examination of the duodenum following enteroclysis

Important abnormalities of the distal duodenum can be missed on the usual enteroclysis examination because of placement of the intubation tube beyond the ligament of Treitz. This can be avoided by extending the examination to include visualization of the duodenum during withdrawal of the nasojejunal tube. On the basis of the case reported here this procedure is suggested for patients with unexplained upper gastrointestinal bleeding in whom the remainder of the small bowel is normal.