Exacerbation of verapamil-induced hyperglycemia with glucagon

To evaluate the effects of verapamil intoxication and glucagon treatment on blood glucose levels in an intact canine model, 15 mg/kg verapamil was administered intravenously over a 30-minute period to mongrel dogs under pentobarbital anesthesia. Animals in the experimental group subsequently were administered 2.5 mg glucagon followed by an infusion of 2.5 mg per hour; control group animals were administered an equal volume of saline. Blood glucose was assessed before verapamil administration (baseline), and at 10 minutes (time 10) and 60 minutes (time 60) after completion of the verapamil infusion. Glucose values were compared between control and experimental groups using Dunnett's method (P = .05). At baseline, no animals were hyperglycemic and there was no difference in glucose levels. Animals in both groups became hyperglycemic after verapamil infusion. At time 10, the experimental group had significantly higher glucose levels (265 +/- 17.1 mg/dL) than the control group (209 +/- 18.3 mg/dL). By time 60, there was no significant difference between glucose values in the control (262 +/- 31.4) and experimental (246 +/- 24.8) groups. It was concluded that verapamil intoxication consistently resulted in hyperglycemia in this model. Glucagon therapy was associated with an early but nonsustained exacerbation of verapamil-induced hyperglycemia.

Influence of 1,3-Dichloropropene, Fenamiphos, and Carbofuran on Meloidogyne incognita Populations and Yield of Chile Peppers

Field trials were conducted during 1986, 1988, 1989, and 1991 to compare the effects of 1,3-dichloropropene, fenamiphos, and carbofuran on yield and quality of chile peppers (Capsicum annuum) in soil infested with Meloidogyne incognita. When compared with untreated plots, numbers of M. incognita juveniles recovered from soil 60 and(or) 90 days after chile pepper emergence were reduced (P = 0.05) following 1,3-D treatment every year except 1986. Nematode numbers were also reduced (P = 0.05) by fenamiphos in 1989. Chile pepper yields were significantly higher than those in untreated control plots (P = 0.05) all 4 years in plots treated with 1,3-D and in 1989 in plots treated with fenamiphos. Use of carbofuran did not significantly reduce nematode numbers or enhance yields in these experiments. Green chile pepper fruit quality was enhanced (P = 0.05) following 1,3-D treatments in 1988 and 1989 but was unaffected by fenamiphos or carbofuran application. Increasing placement depth of 1,3-D from 28 to 48 cm increased (P = 0.05) red chile pepper yield compared with that obtained with conventional placement in 1988 only, and did not affect green chile pepper yield.

Intravenous versus rectal prochlorperazine in the treatment of benign vascular or tension headache: a randomized, prospective, double-blind trial

STUDY OBJECTIVE

To compare the effectiveness of i.v. and PR prochlorperazine for treatment of acute benign vascular or tension headache.

DESIGN

Prospective, randomized, double-blind trial.

SETTING

University emergency department with 50,000 annual census.

PARTICIPANTS

Forty-five adult patients enrolled on 46 visits.

INTERVENTIONS

Patients received 10 mg prochlorperazine i.v. and placebo suppository or 25 mg prochlorperazine PR and placebo injection. Pain assessment was made using a 10-cm visual-analog scale; scores were analyzed using Wilcoxon/Kruskal-Wallis rank-sum tests (alpha of .01).

RESULTS

Mean 60-minute pain scores for i.v. and PR groups were 0.6 and 3.5, respectively (P = .0002). Two patients (8.7%) in the i.v. group and six patients (26.1%) in the PR group required rescue analgesia (P = .12).

CONCLUSION

i.v. prochlorperazine appears to provide more effective relief than PR prochlorperazine for benign vascular or tension headaches.

Accuracy of fingerstick glucose determination in patients receiving CPR

Recent demonstration of the dangers of hyperglycemia in the setting of cerebral hypoperfusion has resulted in recommendations to abandon the long-standing practice of empiric administration of dextrose to patients with altered mental status. Patients receiving basic cardiopulmonary resuscitation (CPR) have been identified as being at particular risk from inappropriate administration of dextrose. We conducted a prospective trial to determine whether the blood glucose of 50 patients receiving CPR could be accurately assessed using a portable rapid-reagent device in the emergency department (ED). We analyzed both capillary and venous blood samples in the rapid-reagent system, using laboratory analysis of venous blood to define the patient's true blood glucose level. Capillary blood analysis identified 8 patients as hypoglycemic; only 3 of these patients were truly hypoglycemic, and 2 patients identified as hypoglycemic by fingerstick were actually hyperglycemic on laboratory analysis. The only instance in which a patient was classified differently by venous rapid-reagent and laboratory analysis occurred when a patient assessed as normoglycemic (169 mg/dL) by the laboratory had a venous rapid-reagent glucose reading of 182 mg/dL (hyperglycemic). We recommend that venous (rather than capillary) blood be used to analyze blood glucose in all patients receiving CPR before dextrose administration is considered.

Emergency department treatment of migraine, tension, and mixed-type headache

The complaint of headache is frequently encountered in the emergency department, but most patients with cephalalgia have a benign etiology for their pain. At least 90% of patients presenting with headache are diagnosed as suffering from benign vascular or muscle-tension (for example, migraine, tension, or mixed-type) headache. There is no consensus on the ideal therapeutic approach to these patients. Classically utilized narcotic therapy suffers from problems with efficacy, relapse, and potential for abuse and addiction. However, other agents have successively proved to be imperfect as well, despite the many therapeutic approaches that have been suggested in the medical literature. While no one drug has emerged as clearly superior for treatment of acute benign headache, recent investigations have clarified the role of certain therapies. This review is intended to familiarize emergency physicians with the latest information on most recommended therapeutic approaches to the patient with headache.

Is oral endotracheal intubation efficacy impaired in the helicopter environment?

INTRODUCTION

Patients transported by helicopter often require advanced airway management. The purpose of this study was to determine whether or not the in-flight environment of air medical transport in a BO-105 helicopter impairs the ability of flight nurses to perform oral endotracheal intubation.

SETTING

The study was conducted in an MBB BO-105 helicopter.

METHODS

Flight nurses performed three manikin intubations in each of the two study environments: on an emergency department stretcher and in-flight in the BO-105 helicopter.

RESULTS

The mean time required for in-flight intubation (25.9 +/- 10.9 seconds) was significantly longer than the corresponding time (13.2 +/- 2.8 seconds) required for intubation in the control setting (ANOVA, F = 38.7, p < .001). All intubations performed in the control setting were placed correctly in the trachea; there were two (6.7%) esophageal intubations in the in-flight setting. The difference in appropriate endotracheal intubation between the two settings was not significant (chi 2 = 0.3; p > 0.05).

CONCLUSION

Oral endotracheal intubation in the in-flight setting of the BO-105 helicopter takes approximately twice as long as intubation in a ground setting. The results support pre-flight intubation of patients who appear likely to require urgent intubation during air medical transport in the BO-105 helicopter.

Bilateral epidural empyemas in an adolescent

Epidural empyema is an unusual cause of headache that may be encountered in the emergency department. The collection of suppurative fluid usually results from local spread of sinusitis, although many other predisposing factors have also been described. Patients with epidural empyema usually present with nonspecific cephalalgia that may be accompanied by fever and leukocytosis but is unlikely to be associated with focal neurological findings. The case of an adolescent who presented to our emergency department twice in 6 days with persistent headache is reported; cranial computed tomography performed on the second visit demonstrated bilateral epidural empyema. This entity is uncommon, but may certainly be encountered by the emergency physician.

Effect of saliva flow rate on saliva phenytoin concentrations: implications for therapeutic monitoring

The effect of atropine-induced reductions in saliva flow rate on saliva phenytoin concentrations were evaluated in a randomised placebo-controlled crossover study in a group of epileptic patients stabilised on the drug. Pretreatment with atropine caused significant reductions in saliva flow rates during the first 4 h, compared to saline. The AUC0-4 h for saliva flow rate was significantly reduced by atropine (245 g vs 327 g) and the saliva phenytoin AUC0-4 h was significantly increased (5.6 micrograms.ml-1.h vs 4.5 micrograms.ml-1.h) without affecting plasma phenytoin concentrations. The saliva/plasma phenytoin AUC0-4 h ratio was therefore significantly increased by atropine (0.15 vs 0.12). However, there was a poor correlation between saliva/plasma phenytoin concentration ratios and saliva flow rates for the two treatments in the individual patients (correlation coefficient ranged from 0.25 to 0.65). These findings demonstrate that saliva phenytoin concentrations are increased by reductions in saliva flow rate. Caution is therefore required when saliva phenytoin concentrations are used for therapeutic monitoring in the presence of factors which may affect saliva flow rate.

Interhospital transfer of cardiac patients: does air transport make a difference?

INTRODUCTION

The purpose of this study was to compare the outcome of interhospital transported cardiac patients for whom bias in selecting transport mode was removed due to helicopter unavailability.

METHODS

Patients with the diagnosis of unstable angina or myocardial infarction who underwent transport by ground only because helicopter transport was not available, were compared to patients transported by helicopter. Patients were matched by gender and referring hospital. Ninety-six patients were studied and both groups were comparable in age, diagnosis, Killip classification, treatment with thrombolytics and post-transport procedures.

RESULTS

There were no statistically significant differences between the groups for mean ICU days (5.3 air vs. 3.5 ground) and mean hospital days (9.9 vs. 8.2, respectively). No differences were detected in the proportions of deaths within 72 hours of arriving at the receiving institution (1/48 air vs. 0/48 ground), but air transportation was associated with more total deaths (9/48 vs. 1/48, respectively).

CONCLUSION

It appears that the interhospital transport of cardiac patients by air offers no outcome advantage over ground transport.

The ability to perform closed chest compressions in helicopters

Critically ill patients are often transported by air ambulances. Although these patients are likely to require cardiopulmonary resuscitation (CPR) during transport, the effects of the air medical transport environment on CPR efficacy have never been studied. A manikin model was used to assess the ability of flight nurses to perform effective chest compressions while in flight and when stationery on the helipad. The results demonstrate that flight nurses were able to perform chest compressions as effectively in the in-flight setting as in the stationary setting. Chest c compressions performed in the BK-117 helicopter were as effective as those performed in the control environment, but compressions performed in the BO-105 were significantly less effective than controls. In conclusion, in a manikin model, chest compressions are substandard in the BO-105 helicopter because of the limited space available in the aircraft.

Upper airway obstruction from tonsillar infection in adults

We report the case of a 23-year-old male who presented to the emergency department with severe upper airway obstruction resulting from infection of the palatine tonsils. Manifestations of tonsillar infection and airway obstruction included hoarseness and extreme difficulty breathing, severe sore throat and inability to swallow liquids or solids. Urgent otolaryngologic consultation was obtained, and the patient was taken directly to the operating suite for nasotracheal intubation with tracheostomy standby. The patient was maintained on broad-spectrum antibiotics and was discharged after a hospital course complicated by pulmonary oedema, tracheitis and difficulty weaning from the ventilator, requiring temporary tracheostomy. The Monospot test was negative for infection with the Epstein-Barr virus (EBV). We could find no previously reported cases of adults with severe palatine tonsillar-induced airway obstruction which was not due to infection with EBV (mononucleosis). The airway management of obstruction due to palatine tonsillar hypertrophy is discussed.

A review of drug use during air medical transport to optimize an air ambulance formulary

INTRODUCTION

The advent of air medical transport has pushed the delivery of critical care medicine into the prehospital arena. As a result, a wide variety of pharmacologic agents must be available in the air medical setting.

PURPOSE

The purpose of this study was to conduct a retrospective review of drugs used during air medical transport to allow a streamlining of the air ambulance formulary.

METHODS

All flights completed since the inception of the study's helicopter air ambulance program in 1985 through September 1991 were analyzed to determine which medications were used in flight. Drugs were counted if they were administered while in flight for either a scene or interhospital transport.

RESULTS

Review of 2,694 flights showed that 45 individual drugs had been routinely carried during the study period. Many of these agents were administered fewer than five times during the six years, and 10 drugs were not used at all.

CONCLUSION

As a result of this investigation, the formulary for our air medical transport service was modified. The authors recommend similar critical audits of drugs carried in flight be performed by other air ambulance services.

Acute toxicity from baking soda ingestion

Sodium bicarbonate is an extremely well-known agent that historically has been used for a variety of medical conditions. Despite the widespread use of oral bicarbonate, little documented toxicity has occurred, and the emergency medicine literature contains no reports of toxicity caused by the ingestion of baking soda. Risks of acute and chronic oral bicarbonate ingestion include metabolic alkalosis, hypernatremia, hypertension, gastric rupture, hyporeninemia, hypokalemia, hypochloremia, intravascular volume depletion, and urinary alkalinization. Abrupt cessation of chronic excessive bicarbonate ingestion may result in hyperkalemia, hypoaldosteronism, volume contraction, and disruption of calcium and phosphorus metabolism. The case of a patient with three hospital admissions in 4 months, all the result of excessive oral intake of bicarbonate for symptomatic relief of dyspepsia is reported. Evaluation and treatment of patients with acute bicarbonate ingestion is discussed.

Effect of an in-flight helicopter environment on the performance of ALS interventions

INTRODUCTION

Patients transported by air ambulance are often critically ill and, thus, have a relatively high likelihood of requiring advanced life support (ALS) measures during transport. Despite this fact, the ability of the air medical crew to perform ALS interventions efficiently while in flight has not been investigated.

SETTING

The study was conducted with BO 105 and BK 117 helicopters and a ground transport unit at a university hospital-based air ambulance service.

METHODS

Ten flight nurses were timed performing various ALS tasks while in flight in each aircraft and in the ground ambulance. Mean times for performance of each task in the aircraft and in the ground unit were analyzed using Dunnett's method for analysis of multiple means; alpha was set at 0.01.

RESULTS

Times required to perform all ALS tasks were significantly increased in the BO 105 setting compared to the setting of the BK 117 or the ground ambulance (p < 0.01). Times for performance of interventions in the BK 117 did not differ significantly from corresponding times in the ground setting.

CONCLUSION

It appears that the environment of the BO 105 may impose limitations on the timely performance of certain ALS interventions.

Controlled trial of an intravenous fluid warmer

INTRODUCTION

In critically ill patients (e.g., trauma victims) prevention of hypothermia is an important goal. Infusion of warm fluids has been addressed in the hospital setting, but not in the air medical transport setting.

PURPOSE

The purpose of this study was to test the efficacy of an intravenous (IV) fluid warming device that is well-suited for the air medical transport environment.

METHOD

The warmer studied was used with IV fluid heated to approximately 38 degrees C (100 degrees F) and evaluated in environmental temperatures of -16 degrees C (3 degrees F), 2 degrees C (36 degrees F), and 22 degrees C (72 degrees F). The warmer group was compared to a control group of similarly treated IV fluids without a warming device. Temperatures were measured at baseline, 15, 30 and 60 minutes.

RESULTS

The 30- and 60-minute fluid temperatures were higher in the warmer than in the control group for all three environmental temperature settings. At 15 minutes, fluid temperatures were higher in the warmer group for the 2 degrees C and -16 degrees C, but not the 22 degrees C, environments. There was no significant drop in temperature in the warmer group in the 22 degrees C and 2 degrees C settings, but a decrease was noted in the -16 degrees C environment. There was a significant drop in the control group at all temperatures tested.

CONCLUSION

The IV fluid warmer tested effectively maintains the temperature of warmed IV fluids in temperatures above 2 degrees C. At -16 degrees C there was significant heat loss, but the loss was significantly less when compared to the control group.

Effects of 1,3-Dicliloropropene for Meloidogyne incognita Management on Cotton Produced under Furrow Irrigation

Field trials were conducted during 1990 to evaluate the effects of preplant soil fumigation with 1,3-dichloropropene (1,3-D) on yield and fiber quality of furrow-irrigated cotton cultivars subjected to high population densities of Meloidogyne incognita. We measured the responses of eight upland cotton cultivars with different levels of root-knot nematode resistance and compared the responses of upland and Pima cottons. Reductions in lint weight ranged from 10 to 52% among cultivars grown in soil without 1,3-D fumigation compared with those grown in treated soil. Meloidogyne incognita reduced yields primarily by reducing the number of bolls on each plant, rather than by decreasing boll size. Cotton fiber quality varied among cultivars but was unaffected by M. incognita in either study. Upland cotton cultivar Acala 1517-88 and M-315/240 sustained less than half the yield reductions observed with M. incognita-susceptible cultivars Deltapine 41 and Paymaster 145. Sixty days after cotton emergence, fewer M. incognita second-stage juveniles were recovered from M-315/240 than all other cultivars.

Paracetamol (acetaminophen) poisoning

Paracetamol poisoning caused by intentional overdose remains a common cause of morbidity. In this article the mechanism of toxicity and the clinical effects and treatment of poisoning, including specific antidotal therapy, are reviewed. Areas for further research directed at reducing morbidity and mortality from paracetamol poisoning are considered.

Delivery of ultrasonic nebulized aerosols to a lung model during mechanical ventilation

Ultrasonic nebulizers may be particularly suitable for the administration of therapeutic aerosols to patients undergoing mechanical ventilation, but the amount of aerosol that reaches the patients' respiratory tract during ultrasonic nebulization has not been adequately studied. The delivery through an endotracheal tube of nebulized aerosols labeled with 99mTechnetium human serum albumin was therefore measured for five commercially available ultrasonic nebulizers using an in vitro model representing mechanical ventilation of an adult patient. Delivery of aerosol through the endotracheal tube ranged from 3.1 +/- 0.3% for Samsonic to 10.1 +/- 2.0% for Portasonic using 3 ml nebulizer solution. Increasing the volume of nebulizer solution to 18 ml (not possible for the Portasonic) increased delivery to 11.5 +/- 2.0 for the DP 100, 8.7 +/- 3.1 for Ultraneb, and 15.9 +/- 1.8% for Samsonic. Addition of a 600 ml aerosol storage chamber to the ventilator circuit increased delivery for the Samsonic (18 ml solution) to 22.3 +/- 5.0%. Aerosol delivery was also increased by reducing the respiratory rate and minute volume and by increasing the inspiratory time settings on the ventilator. These results confirm the potential value of ultrasonic nebulizers during mechanical ventilation and indicate that clinical trials in ventilated patients are warranted.

Therapeutic aerosols in children

The use and variety of drugs administered to children as inhaled aerosols is increasing, but little is known about how much drug reaches the lung and how it is distributed there in different age groups. In this article the reasons for measuring aerosol deposition in children are discussed and the potential methods for doing this described. Of the methods available, only the use of radiolabelled aerosols gives accurate information on total lung deposition and distribution. The potential risk of the radiation exposure required for these measurements varies with the age of the child but seems to be small. Properly designed studies are expected to clarify the factors affecting lung deposition in children and identify methods of inhalation associated with efficient and predictable delivery of the drug. Measurements of radioaerosol deposition may therefore be justified in children when this information is expected to lead to improvements in the effectiveness or safety of their treatment.

The influence of steady-state ciprofloxacin on the pharmacokinetics and pharmacodynamics of a single dose of diazepam in healthy volunteers

The effects of pretreatment with a seven day course of ciprofloxacin on pharmacokinetics and pharmacodynamics of an intravenous (5 mg) dose of diazepam were investigated in a group of 12 healthy volunteers in a double-blind placebo-controlled crossover study. Ciprofloxacin pretreatment significantly reduced diazepam CL (without ciprofloxacin: 19.5 ml.h-1 kg-1; with ciprofloxacin: 12.3 ml.h-1 kg-1). Diazepam t1/2 was also prolonged (without ciprofloxacin: 36.7 h; with ciprofloxacin: 71.1 h), but volume of distribution was unaltered (without ciprofloxacin: 1.1 l.kg-1; with ciprofloxacin: 1.1 l.kg-1). However, no significant changes were detected in psychometric tests of digit symbol substitution, tapping rate and short memory, as well as levels of concentration, vigilance and tension measured by visual analogue scales.