PubMed HealthSearch

Biomedical subjects

D Tandberg

Publications and source records attributed to D Tandberg.

At least 19 recordsLinked to original sources

A controlled comparison of self-rated sleep complaints in acute and chronic nightmare sufferers.

A cross-sectional study was performed to retrospectively assess self-rated sleep complaints in three groups of subjects: controls without nightmares (N = 77), acute nightmares sufferers (< 6 months duration, N = 36), and chronic nightmare sufferers (> 6 months duration, N = 128). Four specific complaints of sleep disturbance were categorically measured to ascertain the presence or absence of the symptom: fear of going to sleep; awakenings from sleep; difficulty returning to sleep; and fitful, restless sleep. Each of the four separate sleep complaints were significantly more common in the acute (p < .0001) and chronic (p < .0001) nightmare groups compared with controls. A summed aggregate score of the four sleep complaints was also higher in both the acute (p < .0001) and chronic groups (p < .0001) compared with controls. Ninety-one percent of all subjects with nightmares reported at least one sleep complaint. Between-group assessments, comparing acute and chronic nightmare sufferers for any of the four variables and the aggregate, demonstrated no statistically significant findings, although a few trends were noted. A dose-response relationship was not observed for nightmare frequency or chronicity for any of the four sleep variables or their aggregate. The relationship between nightmares and disturbed sleep is discussed.

Adult

Cerumen occlusion lowers infrared tympanic membrane temperature measurement.

OBJECTIVE: To examine the effect that cerumen occlusion of the ear canal has on infrared tympanic membrane temperature measurement. METHODS: A prospective, randomized, single-blind human study was carried out in a university hospital observation unit. The subjects were a convenience sample of human volunteers ages 18 years or older who did not have cerumen occlusion or scarred tympanic membranes. A paraffin-coated human cerumen plug was placed in one randomly chosen ear, and after 20 minutes of equilibration the temperature of each ear was measured with an infrared thermometer. Analysis of the difference in mean temperature between the occluded and nonoccluded ears was by Student's paired t-test. RESULTS: Infrared tympanic membrane temperatures were measured in 43 subjects aged 21 to 58 years. The mean temperature of the occluded ear canal was 0.3 degrees C lower than that of the opposite ear canal (p = 0.0001, 95% CI 0.16-0.45 degrees C). CONCLUSION: Cerumen occlusion of the ear canal causes underestimation of body temperature measure by infrared tympanic membrane thermometry.

Adult

Dehydration and orthostatic vital signs in women with hyperemesis gravidarum.

OBJECTIVES: To assess the hydration status of women presenting to an ED with hyperemesis gravidarum and to determine whether clinically relevant changes in orthostatic vital signs occur. METHODS: A convenience sample of 23 pregnant women who had hyperemesis gravidarum, with each patient serving as her own control. The study took place in the ED observation unit of an urban teaching hospital. Women who had pregnancies of < or = 16 week's gestation who had been vomiting for at least 24 hours were included. Supine and standing pulse rates and blood pressures (BPs) were measured sequentially after 5 minutes in each position. Patient weight and urine specific gravity (SG) also were recorded. After 6 L of lactated Ringer's solution was infused over a 12-hour period, the same measurements were repeated. Pre- and posthydration changes were analyzed using the paired t-test. RESULTS: The mean treatment weight gain as a percentage of the total body weight was 5.6% +/- 2.2% (mean +/- SD). The urine SG decreased from 1.027 +/- 0.004 to 1.008 +/- 0.003 (p < 0.001). The mean change in systolic BP upon assuming the standing position was -8.3 +/- 12.7 mm Hg before hydration vs 2.9 +/- 7.8 mm Hg after hydration (p < 0.001). The corresponding change in mean diastolic BP was 3.7 +/- 10.9 mm Hg before hydration vs 8.6 +/- 10.9 mm Hg after hydration (p = 0.12). The mean change in pulse rate upon standing was 26.8 +/- 14.5 beats/min before hydration vs 14.5 +/- 10.1 beats/min after hydration (p = 0.002). CONCLUSIONS: Women who present to the ED with hyperemesis gravidarum are significantly dehydrated and experience measurable improvement in postural pulse rate and systolic BP changes with rehydration. However, the presenting orthostatic changes lack sufficient sensitivity to be effectively used as quantitative screening tests for dehydration.

Adolescent

Time series forecasts of poison center call volume.

We tested the hypothesis that time series analysis can provide accurate predictions of future poison center telephone call volume by a prospective stochastic time series modeling of calls to a university-based regional poison center. All callers evaluated and managed during two sequential years had the time and date of the call recorded in a computer database. Time series variables were formed for poison center calls per hour. Prediction models were developed from the 1992 data and included four types: raw observations, moving average, means with moving average smoothing, and autoregressive integrated moving average. Forecasts from each model were tested against observations from the first 26 weeks of 1993. Each model's adequacy was tested on residuals by autocorrelation functions, integrated periodograms, linear regression, and differences among the variances. A total of 44,584 calls were received in 1992 and 24,781 in the first half of 1993. Large periodic variations in call volume with time of day were found (p < 0.001). The model based on arithmetic means of each hour of the week with three-point moving average smoothing yielded the most accurate forecasts and explained 58.5% of the variation observed in the 1993 test series (p < 0.001). Time series analysis can provide powerful, accurate short range forecasts of future poison center telephone call volume. Simpler, less expensive models performed best in this study.

Computers

Floating nights: a 5-year experience with an innovative ED schedule.

An academic emergency group was surveyed to determine if scheduling night shifts in blocks ("floats") improved attitudes and functioning. Seven physicians worked most of their nights as floats. Another four chose only isolated nights. Float physicians were surveyed for isolated and block nights. Faculty in the float group had poorer attitudes compared with the nonfloat group when both worked isolated nights (P = .0053). Working night floats eliminated these differences. Float physicians had more difficulty with sleep regardless of their schedule. They took longer to recover from an isolated night shift, drank more coffee, and used more postcall sedatives than their colleagues (P = .0108). The ideal night float was 2 to 4 weeks with shifts less than 10 hours, but careful attention to sleep hygiene remained essential. Physicians have different adaptability to night work. For some, concentrating night shifts is a useful strategy for improving shift work. This would require shorter shifts and larger groups than are now commonplace.

Attitude

Cervical spine movement during airway management: cinefluoroscopic appraisal in human cadavers.

The objective of this study was to determine which airway maneuvers cause the least cervical spine movement. A controlled laboratory investigation was performed in a radiologic suite, using eight human traumatic arrest victims who were studied within 40 minutes of death. All subjects were ventilated by mask and intubated orally, over a lighted oral stylet and flexible laryngoscope, and nasally. Cinefluoroscopic measurement of maximum cervical displacement during each procedure was made with the subjects supine and secured by hard collar, backboard, and tape. The mean maximum cervical spine displacement was found to be 2.93 mm for mask ventilation, 1.51 mm for oral intubation, 1.65 mm for guided oral intubation, and 1.20 mm for nasal intubation. Ventilation by mask caused more cervical spine displacement than the other procedures studied (ANOVA: F = 9.298; P = .00004). It was concluded that mask ventilation moves the cervical spine more than any commonly used method of endotracheal intubation. Physicians should choose the intubation technique with which they have the greatest experience and skill.

Airway Obstruction

The effect of pH buffering on reducing the pain associated with subcutaneous infiltration of bupivicaine.

The authors propose that pH buffering of bupivicaine with sodium bicarbonate reduces the pain associated with its local subcutaneous infiltration. In a double-blind, prospective study, 62 healthy adult volunteers received a 0.5 mL subcutaneous infiltration of 0.5% buffered bupivicaine into the dorsum of a randomly chosen hand. The pH was adjusted to 7.0 by adding 0.05 mL of sodium bicarbonate (1 mEq/L [corrected]) to 10 mL vials of commercially available bupivicaine (1:200 dilution). The control hand was injected with the same amount of unbuffered agent. Pain was scored after each infiltration using a nonsegmented visual analogue scale. Student's t-test for paired measurements was used to analyze intergroup pain score differences. Forty-three subjects (69%) reported less pain with buffered bupivicaine and only 17 (27%) noted a modest increase: two subjects (3%) reported no difference. The mean pain score for the buffered agent was 22 mm compared with 30 mm for the control. The mean difference (control-experimental) was 8 mm (t = 4.64, df = 61, P less than .001). The authors conclude that the addition of sodium bicarbonate to bupivicaine reduces the pain associated with its local infiltration.

Adult

Systemic anaphylaxis after ingestion of a psyllium-containing breakfast cereal.

Allergic reactions have been described as an occupational hazard among nurses and pharmaceutical workers who handle psyllium-containing laxatives. This study reports the case of a 38-year-old female nurse who ingested a bowl of psyllium-containing Heartwise Cereal (Kelloggs, Battle Creek, MI) and 25 minutes later developed severe systemic anaphylaxis manifested by hypotension, a feeling of constriction in the throat, hoarseness, dyspnea, wheezing, generalized pruritus, urticaria, and vomiting. She was treated with epinephrine, normal saline, diphenhydramine, and methylprednisolone, and recovered completely. Subsequent IgE immunoblot assay was strongly reactive to psyllium. Ingestion of psyllium-containing breakfast foods by sensitized individuals can be associated with life-threatening systemic anaphylaxis.

Adult

Magnetic resonance imaging in minor head injury.

STUDY OBJECTIVES: To investigate the role of cranial magnetic resonance (MR) imaging in evaluating patients discharged from the emergency department after minor head injury. DESIGN: A prospective blinded cohort study. SETTING: University hospital ED. TYPE OF PARTICIPANTS: Fifty-eight patients with minor head injury who were discharged from the ED with written head injury instructions. Patients admitted to the hospital were excluded. INTERVENTIONS: Ultra-low-field cranial MR scans were performed on patients within 24 hours of discharge. Scans were read blindly by two radiologists. MEASUREMENTS AND MAIN RESULTS: Fisher's exact test was used to compare symptoms in patients with abnormal and normal MR scans. There was no significant difference in symptoms between patients with abnormal and those with normal scans (P greater than .10). The proportion of abnormal MR scans was analyzed using the binomial distribution. Six of the 58 patients (10.3%) had traumatic intracranial abnormalities (proportion, 0.103; SD, 0.04; 95% CI, 0.04-0.21). Three had cortical contusions, and three had small subdural hematomas. Two of the six patients with abnormal MR scans, both with small subdural hematomas, had normal computed tomography scans. CONCLUSION: Ten percent of patients discharged from the ED after minor head injury had abnormal ultra-low-field cranial MR scans. Additional research is needed to establish the clinical importance of this unexpected observation.

Adolescent

Under-reporting of contaminated needlestick injuries in emergency health care workers.

STUDY HYPOTHESIS: There is considerable under-reporting of contaminated occupational needlestick and other sharp object injuries among emergency health care workers. POPULATION: A convenience sample of emergency physicians, emergency nurses, and emergency medical technicians (EMTs). METHODS: A survey instrument eliciting demographic and work-related factors was developed and administered; survey items included age, sex, occupation, years in occupation, number of procedures performed per week, number of contaminated needlestick (and other "sharps") injuries recalled, and number of these injuries formally reported during the previous five years. Nonsegmented visual analog scales were used to assess eight attitudes possibly associated with nonreporting. Analysis was by analysis of variance and multiple linear regression with stepwise variable election. RESULTS: Two hundred fifty-nine subjects recalled 643 contaminated exposures during the five-year study period, but only 228 (35%) were formally reported. One or more injuries occurred in 55% of EMTs compared with 72% of nurses and 80% of physicians (P less than .05). Physicians recalled a mean of 3.8 contaminated exposures, whereas nurses recalled 2.8 and EMTs recalled only 1.8 (P less than .05). Physicians formally reported a mean of 0.26 exposures, whereas EMTs reported 0.85 and nurses reported 1.25 (P less than .05). Physicians formally reported only one eighth of their injuries compared with EMTs and nurses, who each reported two thirds of these events (P less than .05). Perception of risk, occupation, years in occupation, and concern about excessive paperwork were the most powerful predictors of low reporting rate (P less than .05). CONCLUSIONS: Work-related contaminated sharp object injuries are under-reported by emergency health care workers, especially emergency physicians.

Accidents, Occupational

Destruction of hearing aid by lightning strike.

A 20-year-old woman was struck by lightning while seeking shelter under a tree. The discharge entered at the site of the victim's behind-the-ear type hearing aid, destroying it. She suffered cardiorespiratory arrest, burns, left ventricular failure, and myoglobinuria, yet recovered fully. It is widely known that carrying a metallic object such as an umbrella or golf club above one's head increases the risk of being struck. However, few people know that small metallic objects worn on the head are similarly dangerous. Persons caught outside in a lightning storm might decrease the probability of being struck by removing all metallic objects from their head.

Adult

Rapid visual colorimetry of peritoneal lavage fluid.

STUDY HYPOTHESIS: That visual colorimetry can be used to rapidly and precisely estimate the erythrocyte count of 1:5 dilutions of simulated peritoneal lavage fluid. POPULATION: Fifty-four normal adult human subjects. METHODS: The automated or chamber RBC count is often used on fluid obtained by peritoneal lavage in patients with abdominal trauma to help determine the need for surgery. Unfortunately, this method sometimes results in excessive delay. We designed and built a simple colorimeter that facilitated rapid direct visual comparison of unknown samples with known color standards. A radiograph view box was used as a light source. Standards were prepared in 16-mm glass tubes to simulate peritoneal lavage fluid with RBC counts ranging from 0 to 140,000 in 10,000 cell/microL increments; 1:5 dilutions with water were used throughout to reduce opacity. Thimerosal was added to unknowns and standards to stabilize color; all samples were kept refrigerated at 4 C when not in use. In a double-blind in-vitro study, each subject matched 20 randomly distributed unknowns ranging from 12,000 to 131,000 erythrocytes/microL to the nearest standard. RESULTS: The mean absolute error for all 1,080 determinations was 3,560 RBC/microL (95% CI = 4,290-4,830; SD = 4,560; t = 39.6; df = 1,079; P less than .001). This method correctly predicted the RBC count to within 9,000 cells/microL 95% of the time. CONCLUSION: Visual comparison of 1:5 dilutions of simulated peritoneal lavage fluid with known color standards can be used to rapidly and precisely estimate the erythrocyte count.

Abdominal Injuries

The effect of local anesthetics on bacterial proliferation: TAC versus lidocaine.

We compared the effect of topical 0.5% tetracaine, 1:2,000 epinephrine, and 11.8% cocaine (TAC) with 1% lidocaine infiltration on bacterial proliferation in experimental lacerations. Forty-eight lacerations were made on the backs of Hampshire pigs, inoculated by injection with infectious doses of Staphylococcus aureus and randomly anesthetized with either topical TAC or lidocaine infiltration. Wounds were sutured, and quantitative cultures were obtained by excision after 48 hours. The mean log10 bacteria per gram of tissue for wounds anesthetized with TAC was 6.818 (95% confidence interval [CI], 6.07 to 7.54) compared with 6.820 (95% CI, 5.91 to 7.75) for those treated with lidocaine; this difference was not significant (P less than .05 by paired two-tailed t test). The probability of failing to detect an intergroup difference of 0.5 log10 bacteria per gram was less than .0001. TAC does not increase bacterial proliferation more than lidocaine infiltration in contaminated experimental porcine lacerations.

Administration, Topical

The knee-chest position does not improve the efficacy of ipecac-induced emesis.

Previous studies have shown that ipecac-induced emesis, even if instituted very early, removes only a mean of 28% to 45% of an ingested tracer. Because vomiting is an ancient reflex that occurs in mammals, reptiles, and other animals, we speculated that, in humans, maintaining a sitting rather than a horizontal posture during induced emesis might decrease the efficacy of gastric emptying. To test this hypothesis, 20 normal fasting adult subjects underwent induced emesis in the knee-chest position on one day and in the sitting position on another. Twenty-five 100-micrograms tablets of cyanocobalamin were ingested as a tracer along with 250 mL tap water. Ten minutes after tracer ingestion, 30 mL ipecac syrup and 640 mL tap water were swallowed. All resulting vomitus was homogenized, frozen, and later assayed for cobalt using atomic absorption spectrophotometry. There was no difference in mean tracer recovery with the two positions: knee-chest, 47.2% v sitting, 46.9% (paired t test, P greater than .95). Analysis of cobalt recovery for all 40 episodes of emesis revealed a mean of 51.2 +/- 23.7 (SD) micrograms out of 108.7 micrograms total cobalt ingested (95% Cl, 43.6 to 58.7 micrograms). This represented 47.1% of the administered tracer dose (95% Cl, 40.1% to 54.0%). Even if initiated only ten minutes after an ingestion, ipecac-induced emesis removes an average of less than half of an ingested tracer dose, with a high degree of intersubject variability. Horizontal patient positioning does not appear to improve the efficacy of this procedure.

Adult

Substances that interfere with guaiac card tests: implications for gastric aspirate testing.

Previous studies have shown that acidic pH and several ingestible substances can cause misleading guaiac tests of gastric aspirates. In this in vitro study, over 100 foods, beverages, and drugs were diluted to concentrations potentially present in the stomachs of outpatients being evaluated for gastrointestinal bleeding. These were mixed with known concentrations of blood and tested with different brands of guaiac cards. Decreased guaiac test sensitivity was associated with activated charcoal, dimethylaminoethanol, red chile, N-acetylcysteine, rifampin, red Jell-O (General Foods Corp, White Plains, NY), orange juice, Pepto-Bismol (Norwich Eaton Pharmaceuticals, Norwich, NY), simethicone, spaghetti sauce, and several red wines. Chlorophyll and methylene blue-containing tablets produced false-positive results, but other blue and blue-green colored tablets did not, except at high concentrations. Previously described false-negative results with vitamin C, bile, and certain antacids were confirmed, as were false-positive results with iodide, bromide, cupric sulfate, iron salts, and hypochlorite. Physicians should exercise caution when interpreting guaiac card tests of gastric aspirates, especially in the outpatient setting.

False Positive Reactions

Ipecac-induced emesis and gastric lavage are equally unpleasant.

It has been widely held that gastric lavage is more unpleasant than ipecac-induced emesis. In fact, patients are occasionally threatened with large rubber tubes in order to persuade them to drink ipecac. To confirm that this assumption exists, we asked 41 emergency physicians and nurses who had never personally undergone either procedure to estimate the discomfort of each using a 10 cm unsegmented visual analog scale. This "naive" group thought that gastric lavage would be significantly more unpleasant than ipecac-induced emesis (mean scores: lavage = 6.46, emesis = 4.94; P less than .001, paired t-test). Using the same methods, we asked 16 health professionals who had undergone both procedures as part of another study to score the recalled unpleasantness of each procedure. Among these who had actually experienced both, there was no significant difference between the mean scores for lavage (4.09) and emesis (4.62) (P greater than 0.5, paired t-test). The mean score difference (lavage minus emesis) for the "naive" group was significantly greater than for the experimental group (1.52 vs -.53, P less than .001, unpaired t-test). Among normal volunteers, ipecac-induced emesis and gastric lavage are equally unpleasant gastric emptying procedures.

Gastric Lavage

MAST conversion of paroxysmal supraventricular tachycardia in Wolff-Parkinson-White syndrome.

A 48-year-old man with Wolff-Parkinson-White syndrome presented with paroxysmal supraventricular tachycardia. Prior episodes had required inpatient drug therapy or cardioversion. Attempts at conversion to normal sinus rhythm with vagal maneuvers were unsuccessful. Inflation of military antishock trousers resulted in rapid termination of the arrhythmia and avoidance of hospitalization.

Anti-Arrhythmia Agents