Analysis of Deaths Related to Anesthesia in the Period 1996-2004 from Closed Claims Registered by the Danish Patient Insurance Association

Background: Anesthesia is associated with complications, and some of them may be fatal. The authors investigated the circumstances under which deaths were associated with anesthesia. In Denmark, the specialty anesthesiology encompasses emergency medicine, chronic and acute pain medicine, anesthetic procedures, perioperative care medicine, and intensive care medicine.

Methods: The authors retrospectively investigated anesthesia related deaths registered by the Danish Patient Insurance Association.

Results: From 1996 to 2004, 27,971 claims were made by the Danish Patient Insurance Association covering all medical specialties, of which 1,256 files (4.5%) were related to anesthesia. In 24 cases, the patient's death was considered to result from the anesthetic procedure: 4 deaths were related to airway management, 2 to ventilation management, 4 to central venous catheter placement, 4 as a result of medication errors, 4 from infusion pump problems, and 4 after complications from regional blockades. Severe hemorrhage caused 1 death, and in 1 case the cause was uncertain.     

Haloperidol impairs classically conditioned nictitating membrane responses and conditioning-related cerebellar interpositus nucleus activity in rabbits

Rabbits, chronically implanted with recording electrodes in the cerebellar interpositus nucleus and following acquisition of a classically conditioned eyelid response, were injected with haloperidol (HAL, 250 micrograms/kg). HAL significantly reduced the number of conditioned responses when a 75 and 85 dB tone conditioned stimulus (CS) was presented but not when a 95 dB tone CS was used. There was a corresponding decrease in interpositus activity at the 75 and 85 dB CS intensities but not at the 95 dB intensity. HAL appeared to disrupt CRs and interpositus activity by increasing the intensity threshold of the tone CS for eliciting conditioned responses. Possible mechanisms for the effect of HAL on neural circuitry involved in classical eyelid conditioning are discussed.     

Conventional versus digital radiographs for intraoperative cervical spine-level localization: a prospective time and cost analysis

BackgroundIn today's health-care environment, operational efficiency is intrinsic to balancing the need for increased productivity driven by rising costs and potentially decreasing reimbursement. Other operational factors kept constant, decreasing the time for a procedure can be viewed as one marker for increased efficiency.PurposeTo prospectively evaluate the time and operating room efficiency differences between the two methods for intraoperative level localization.Stydy designProspective nonrandomized study.Patient sampleProspective consecutive patients undergoing a single-level anterior cervical discectomy and fusion (ACDF) with plate and allograft.Outcomes measuresTime for performance and interpretation of intraoperative localization radiograph.MethodsThis is a prospective nonrandomized study of patients treated consecutively with a single-level ACDF with allograft and plating. All the patients underwent a conventional approach to the cervical spine. After exposure, a spinal needle was placed in the exposed intervertebral disc and a radiography was performed. Either a conventional or a digital radiography was used in each case.ResultsEighteen patients were enrolled in this study. Ten patients underwent localization with conventional radiography, whereas eight patients underwent localization with digital imaging. The mean time for conventional radiography was 823 seconds (standard deviation [SD], 159), and for digital, it was 100 seconds (SD, 34; p<.001).ConclusionsCurrent technology provides options for level localization. Digital imaging provides equally accurate information as conventional radiography in a significantly reduced amount of time. Image quality, ease or archival, and manipulation provided by digital radiography are superior to those by provided fluoroscopy. Keeping operational factors constant, decreasing the time for a procedure, and increasing the efficiency of the environment may be viewed as a surrogate for improving the cost basis for a procedure.     

The effect of naloxone on the preoperative gastric volume and pH

The effect of 4 mg oral naloxone on preoperative gastric volume and pH of gastric aspirate was studied in a double-blind, randomized study. Twenty patients received 10 ml of naloxone (4 mg) mixed with 10 ml of orange juice, and 20 patients received 10 ml of isotonic saline mixed with 10 ml of orange juice, 2 h before surgery. Gastric content was obtained immediately after intubation of the trachea. No significant difference in gastric volume and pH of gastric aspirate was found between the two groups. It is concluded that naloxone does not affect gastric emptying and gastric acid secretion to a degree great enough to protect against aspiration of gastric contents into the lungs.     

Useful predictors of bile duct stones in patients undergoing laparoscopic cholecystectomy. McGill Gallstone Treatment Group.

OBJECTIVE: The authors determined the most useful predictors of common bile duct (CBD) stones as diagnosed by endoscopic retrograde cholangiopancreatography (ERCP) in patients who underwent laparoscopic cholecystectomy (LC). METHODS: Prospective and retrospective collection of historical, biochemical and ultrasonographic data was used. Receiver operating characteristics curve analysis was used to determine optimal biochemical cut-off values. Multivariate analysis using logistic regression with generation of the best model identifying independent predictors of CBD stones also was employed. Prospective validation of the model was performed on an independent group of patients. RESULTS: Endoscopic retrograde cholangiopancreatographies were performed before LC in 106 patients, and after LC in 33. Only four of ten clinical variables evaluated independently predicted the presence of CBD stones. The optimal model predicted a 94% probability of CBD stones in a patient older than 55 years of age who presented with an elevated bilirubin (over 30 mumol/L) and positive ultrasound findings (a dilated CBD, and a CBD stone seen on ultrasound). This model was validated prospectively in a subsequent series of 49 patients in which the probability of CBD stone was only 8% when all four predictors were absent. CONCLUSIONS: The identified independent clinical predictors of a CBD stone helps select a population of symptomatic gallstone bearers who benefit most from cholangiographic assessment.     

A degU-containing SP beta prophage complements superactivator mutations affecting the Bacillus subtilis degSU operon.

The Bacillus subtilis degSU two-gene operon encodes a two-component regulatory system which positively controls expression of a variety of genes encoding degradative enzymes. Point superactivator mutations in either degS or degU increase the production of these enzymes. A specialized transducing SP beta phage which partially complements several of these mutations was isolated from a phage library of the B. subtilis chromosome. This phage was shown to contain the degU (wild-type) gene. This unexpected co-dominance is discussed.     

Rabbit classically conditioned eyelid responses do not reappear after interpositus nucleus lesion and extensive post-lesion training.

The left eyelid responses of four rabbits were classical conditioned by pairing a tone conditioned stimulus and air puff unconditioned stimulus. After conditioned responses were well-established, the left interpositus nucleus was lesioned and 150-200 post-lesion training sessions, distributed over 10 months, were given. In three of the rabbits, no anticipatory conditioned responses were observed on paired trials and responses were at or below spontaneous blinking rates on 2,500 ms CS-alone trials that were also presented. Post-lesion conditioned responses were present when the right side was trained. The fourth rabbit showed few post-lesion conditioned responses on paired trials but eventually showed 80% conditioned responses on tone-alone trials. Histological analysis of the lesion extents indicate that a portion of the anterior interpositus nucleus was spared in this rabbit. These results argue that unlike other cerebellar lesion effects reported in the literature, where some recovery of function is normally noted, the effects of interpositus nucleus lesions are somewhat unique in that conditioned response abolition is seen as long as 10 months after the lesion.     

Traumatic giant aneurysms of the intracranial carotid artery presenting long after head injury

Three patients presented with giant aneurysms of the intracranial internal carotid artery that became symptomatic with expanding mass effects 4-10 years after severe head trauma accompanied by skull base injuries at the site of aneurysm formation. These aneurysms are therefore considered to be late manifestations of traumatic vessel disruption. Posttraumatic aneurysm growth was documented in one case of a supraclinoidal aneurysm. One intracavernous aneurysm was combined with a traumatic carotid-cavernous sinus fistula. Although the origin of intracranial aneurysms is usually considered to be traumatic only within a period of weeks or months after head injuries, giant aneurysms of the intracranial internal carotid may represent late complications of trauma in a number of cases.