Comparison of bretylium and lidocaine in the prevention of ventricular fibrillation after aortic cross-clamp release in coronary artery bypass surgery.

The authors compared bretylium and lidocaine for reducing the incidence and persistence of ventricular fibrillation following aortic cross-clamp release performed during coronary artery bypass surgery. Thirty-three adult patients scheduled for elective bypass surgery were randomly assigned in a double-blind fashion to receive a bolus of bretylium, 10 mg/kg, lidocaine, 2 mg/kg, or saline, in equal volumes prior to the release of the aortic cross-clamp. Coronary artery bypass surgery was conducted using standard cardiopulmonary bypass (CPB) procedures with systemic cooling to 24 degrees to 28 degrees C. Temperature, arterial blood gases, and electrolytes were recorded. After clamp release, the first electrical rhythm was noted. Abnormal rhythms (ventricular fibrillation) were allowed to persist for 1 to 2 minutes, and if spontaneous conversion to a supraventricular rhythm did not occur, defibrillation with internal DC countershocks was applied. Patients were compared with respect to occurrence of ventricular fibrillation, need for DC countershocks, antiarrhythmic drugs, and inotropic support. There was no significant difference among the groups with respect to age, sex, preoperative medications, past medical histories, ejection fractions, average number of bypasses, cross-clamp times, or temperatures during bypass. The incidence of ventricular fibrillation after aortic cross-clamp removal was: saline 91%, lidocaine 64% (P less than 0.01), and bretylium 36% (P less than 0.01). The number of countershocks required to defibrillate, while lower in the bretylium group, did not reach statistical significance. After cardiopulmonary bypass, cardiac output and systemic vascular resistance were comparable. Bretylium warrants further study in this setting.

Rapid-sequence orotracheal intubation: a comparison of three techniques.

The authors compared tracheal intubating conditions using three techniques for rapid-sequence orotracheal intubation. Sixty patients were randomly assigned to one of three groups: priming with vecuronium (0.01 mg/kg priming dose, 4-min priming interval, 0.14-mg/kg intubating dose along with thiopental 4-6 mg iv); timing with vecuronium (0.15-mg/kg intubating dose given before thiopental and timed to weakness of hand grip); and succinylcholine (1.5 mg/kg). Blinded intubators graded intubating conditions 60 s after the induction of anesthesia with thiopental. Intubation scores in the succinylcholine group were significantly better than in the priming group (P = 0.009). Intubation scores of the succinylcholine and the timing groups were not significantly different. Use of the timing principle for rapid-sequence orotracheal intubation is a reliable alternative in cases where succinylcholine is contraindicated.

Success of reentry into anesthesiology training programs by residents with a history of substance abuse.

To determine incidence and outcome of reentry into anesthesiology training programs by residents with histories of substance abuse, a survey was sent to the 159 US anesthesiology training programs. One hundred thirteen (71%) responded, with 82 (73%) submitting at least one case report of substance abuse. A total of 180 case reports were submitted, including 26 in which the resident died as a result of substance abuse. The prevalence of substance abuse among trainees was 2%. Sixty-one (74%) of the responding training programs submitted a total of 113 case reports of resident reentry into anesthesiology training. The success rate of reentry in the parenteral opioid abuser group was 34% (27/79). The success rate of reentry for the nonopioid abuser group was 70% (16/23). There were 14 cases of suicide or lethal overdose among trainees who were allowed to reenter anesthesiology training. Death as the initial relapse symptom occurred in 16% (13/79) of the parenteral opioid abusers who were allowed to reenter anesthesiology training. This study suggests that drug rehabilitation followed by redirection into another specialty may be the most prudent course for the anesthesiology trainee who abuses parenteral opioids.

False indication of arterial oxygen desaturation and methemoglobinemia following injection of methylene blue in urological surgery.

The pulse oximeter serves as an indicator of arterial oxygen saturation. We present two cases in which methylene blue injection during urological surgery appeared to cause arterial oxygen desaturation by pulse oximetry and methemoglobinemia by arterial blood gas co-oximetry. Methylene blue interferes with light absorption and gives a false estimate of the percentage of oxyhemoglobin and arterial oxygen saturation. The co-oximeter interprets methylene blue as methemoglobin and gives a false indication of methemoglobinemia. The surgical team must be familiar with conditions and agents that interfere with their ability to safely monitor surgical patients.

A comparison of pulse oximeters during helicopter flight.

Pulse oximetry would be an invaluable parameter to monitor during patient transport. While original models of oximeters were not battery powered nor very portable, this has changed. Seven currently available commercial pulse oximeter models were evaluated in the noisy vibration-prone environment of a helicopter. Three (3) units were judged to be unacceptable on the basis of weight, duration of battery life, or lack of ease of use. In two (2) units, the sampling algorithms appeared to interface with their performance. Of the seven (7) units tested, two (2) units were found to be reliable, portable, and easy to use. The use of portable pulse oximetry monitors should rapidly become routine during the transport of critically ill patients.

Clinical evaluation of commonly used blood administration sets.

Five commonly available blood transfusion sets, the Fenwall Blood Recipient set, the Abbott HEMAR Y-type Blood Set, the Bentley Infusion Blood Set (PFF-100), the Medex Hi-Flo TraumaR Quad Set (MX 884) and the Pall Ultipor Transfusion Set with Filter are compared. Flow rates and lifespan are evaluated by measuring the time required for 150 mL aliquots of homogeneous units of human red blood cells to pass through the devices under 300 mmHg constant pressure. Microfiltration of blood is briefly reviewed.

Rapid tracheal intubation with vecuronium: the timing principle.

A method of administration of vecuronium for intubation that allows excellent intubating conditions in 60 seconds after the induction of anesthesia is described. Patients were divided into three groups based on the dose of vecuronium given. These patients were given either 0.10 mg/kg, 0.15 mg/kg, or 0.20 mg/kg of vecuronium intravenously. Intubating doses of vecuronium were given prior to the induction of anesthesia with sodium thiopental. Administration of the sodium thiopental was timed to the onset of clinical weakness in each patient.

Sphenopalatine ganglion blocks for the treatment of nicotine addiction.

The purpose of this study was to investigate the effects of sphenopalatine ganglion block upon the physical symptoms of nicotine withdrawal in a double-blind placebo-controlled study. Seventeen patients completed a course of treatment which involved daily intranasal application of local anesthetic (bupivacaine or cocaine) or saline over the sphenopalatine ganglion. The reported numbers of daily symptoms of physical discomfort were recorded during the preprocedure period. Analysis of variance results indicated that patients in all three groups experienced a significant decline in the number of symptoms of physical discomfort over the six-day withdrawal period. Further findings provided evidence of significantly fewer symptoms of discomfort for patients in the anesthetic treatment groups than in the placebo control group, though no statistically significant difference emerged between the two anesthetic treatment groups. Accelerated alleviation of discomfort during nicotine withdrawal may increase the success of smoking cessation.

Lactational responses of dairy cows to diets containing regular and high oleic acid sunflower seeds.

Ten Holstein cows were used in a 15-wk nested factorial to evaluate the response to diets containing added fat from sunflower seeds high (greater than 65%) in linoleic acid (regular sunflower seeds) or high (80%) in oleic acid (high oleic acid variety sunflower seeds). Replicated periods were of 5 wk each, with data collected the last 3 wk of each period. Total mixed diets were 40% corn silage (DM basis), 15% alfalfa hay, and 45% concentrate mix. Concentrate mixes were control, 20% regular sunflower seeds, or 20% high oleic acid sunflower seeds in place of portions of the corn and soybean meal. Yields of milk (27.9, 25.4, and 28.8 kg/d) were similar for all diets, while 4% FCM (24.0, 19.2, and 24.0 kg/d) and SCM (24.8, 20.2, and 24.8 kg/d) were lower when cows were fed regular sunflower seeds. Percentages of fat (3.14, 2.43, and 2.92%) were reduced when cows were fed regular sunflower seeds, but protein (3.00, 3.24, and 3.03%) and total solids (12.12, 11.34, and 11.82%) were similar for all diets. Milk fat from cows fed regular sunflower seeds contained the highest proportions of unsaturated fatty acids with the lowest proportions from cows fed the control diet. Dry matter intakes (22.8, 20.6, and 21.9 kg/d) were similar. Molar percentages of ruminal acetate were lower and propionate higher when cows were fed regular sunflower seeds than when fed high oleic acid sunflower seeds or control. The fatty acid composition of dietary fat influenced the fatty acid composition of cows milk.

Radionuclide-anesthetic flow study: a new technique for the study of regional anesthesia.

A new technique to study the dynamics of in vivo distribution of regional anesthetics is described. Five hundred microcuries of technetium-99m diethylenetriaminepentaacetic acid (DTPA) added to the anesthetic in a syringe prior to injection allows both dynamic and static imaging to assess the initial distribution of the injected anesthetic. Superimposed bone scans or transmission scans help delineate anatomy. The radionuclide-anesthetic flow study is a simple, safe technique to investigate both the spread of regional anesthetics and the factors that affect it.

Effect of carbohydrate on protein solubility.

The effect of covalently attached carbohydrate on the solubility of a number of proteins has been examined by the PEG precipitation technique. Both increases and decreases in solubility are observed depending on the state of glycosylation, the type of protein, and temperature. It is concluded from this data and associated apparent thermodynamic parameters that a general role for carbohydrate in the solubilization of proteins is not currently experimentally supportable.