David R Nelson
Houston Methodist Hospital
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Annals of Emergency Medicine | 1999
Eric T Boie; Gregory P. Moore; Chad Brummett; David R Nelson
STUDY OBJECTIVESnNo large study has addressed whether parents want to be present when invasive procedures are performed on their children in the emergency department. We conducted a survey to address this question.nnnMETHODSnThe study used a self-administered, written survey consisting of 5 pediatric scenarios with increasing level of procedural invasiveness. Parents in an urban, teaching hospital ED waiting area were asked to participate.nnnRESULTSnOf 407 persons asked to participate, 400 (98%) completed the survey. The number of parents expressing a desire to be present during a procedure performed on their child was 387 (97.5%) for venipuncture of the extremity, 375 (94.0%) for laceration repair, 341 (86.5%) for lumbar puncture, and 317 (80.9%) for endotracheal intubation. For a major resuscitation scenario, 316 (80.7%) wished to be present if their child were conscious during the resuscitation, 277 (71.4%) wanted to be present if their child were unconscious during the resuscitation, whereas 322 (83.4%) indicated a desire to be present if their child were likely to die during the resuscitation. Of the 400, 261 (65.3%) wished to be present for all 5 scenarios. Only 26 (6.5%) wanted the physician to determine parental presence in all 5 scenarios.nnnCONCLUSIONnMost parents surveyed would want to be present when invasive procedures are performed on their children. With increasing procedural invasiveness, parental desire to be present decreased. However, most parents would want to be in attendance if their child were likely to die, and nearly all parents want to participate in the decision about their presence.
Annals of Emergency Medicine | 1998
John S Bradley; Geoffrey L Billows; Michael Olinger; Steven P Boha; William H. Cordell; David R Nelson
STUDY OBJECTIVEnTo determine whether basic emergency medical technicians (EMT-B) can perform prehospital oral endotracheal intubation with success rates comparable to those of paramedics.nnnMETHODSnThis was a nonrandomized, controlled trial using historical controls. Seven basic life support emergency medical services systems in six counties and their corresponding emergency departments in rural Indiana participated. Eighty-seven full-time EMTs with no prior or concurrent paramedic training volunteered for intubation training. Apneic prehospital patients aged 16 years or older without an active gag reflex or massive facial trauma were eligible for intubation and study enrollment. The EMTs completed a 9-hour didactic and airway manikin training course in direct laryngoscopic endotracheal intubation. The course was adapted from the national paramedic curriculum.nnnRESULTSnThirty-four (39%) of the EMT-Bs attempted to intubate 57 eligible patients. In 49.1% of these patients, successful endotracheal tube placement was confirmed by the receiving physician (95% confidence interval, 36.4% to 61.9%); in contrast, the prehospital intubation success rates from three previous studies of manikin-trained paramedics ranged from 76.9% to 90.6% (P < .001). Complications included five (9%) inadvertent extubations, two endotracheal tube cuff ruptures, two prolonged intubation attempts, and one mainstem bronchus intubation. There were no unrecognized esophageal intubations. Two of the seven EMS agencies did not report any intubation data.nnnCONCLUSIONnRural EMTs with didactic and airway manikin training failed to achieve prehospital intubation success rates comparable to those of paramedic controls. Possible explanations include training deficiencies, poor skill transference from manikin to human intubation, infrequent intubation experiences, and inconsistent supervision.
Annals of Emergency Medicine | 1998
Jason C Hollingsworth; Carey D. Chisholm; Beverly K. Giles; William H. Cordell; David R Nelson
STUDY OBJECTIVESnTo determine how emergency physicians and nurses spend their time on emergency department activities.nnnMETHODSnAn observational time-and-motion study was performed at a 36-bed ED with annual census of 84,000 in a central city teaching hospital sponsoring an emergency medicine residency program. Participants were emergency medicine faculty physicians, second- and third-year emergency medicine resident physicians, and emergency nurses. A single investigator followed individual health care providers for 180-minute periods and recorded time spent on various activities, type and number of activities, and distance walked. Activities were categorized as direct patient care (eg. history and physical examination), indirect patient care (eg. charting), or non-patient care (eg. break time).nnnRESULTSnOn average, subjects spent 32% of their time on direct patient care, 47% on indirect patient care, and 21% on non-patient care Faculty physicians, residents, and emergency nurses differed in the time spent on these three categories of activities. Although the overall time spent on direct patient care activities was not significantly different, emergency nurses spent more of their time (2.2%) providing comfort measures (a subcategory of direct patient care) than did faculty physicians (.05%) or resident physicians (.03%). Emergency nurses spent 38.9% of their time performing indirect care, whereas faculty physicians spent 51.3% and resident physicians 53.7%. Resident physicians spent more time charting than did faculty physicians or emergency nurses (21.4%, 11.9%, and 6.9%, respectively). Emergency nurses spent more time on personal activities than did physicians, and faculty physicians walked less than either emergency nurses or resident physicians.nnnCONCLUSIONnEmergency physicians and nurses spent almost half of their time on indirect patient care. Physicians spent significantly more time on indirect patient care activities and significantly less time on personal activities than did nurses.
Annals of Emergency Medicine | 1995
William H. Cordell; Jason C Hollingsworth; Michael L. Olinger; Steven J Stroman; David R Nelson
STUDY OBJECTIVESnAlthough spine boards are one of the main EMS means of immobilization and transportation, few studies have addressed the discomfort and potential harmful consequences of using this common EMS tool. We compared the levels of pain and tissue-interface (contact) pressures in volunteers immobilized on spine boards with and without interposed air mattresses.nnnDESIGNnProspective crossover study.nnnSETTINGnEmergency department of Methodist Hospital of Indiana, Indianapolis, Indiana.nnnPARTICIPANTSnTwenty healthy volunteers who had not taken any analgesic drugs in the preceding 24 hours, were not experiencing any pain at the time of the study, and did not have history of chronic back pain.nnnINTERVENTIONSnTo simulate prehospital transport conditions, we immobilized volunteers with hard cervical collars and single-buckle chest straps on wooden spine boards with or without commercially available medical air mattresses. The crossover order was randomized. After 80 minutes, immobilization measures were discontinued and the subjects were allowed to get off the boards for a recovery period of 60 minutes. Subjects were then studied for a second 80-minute period with the opposite intervention. At baseline and at 20-minute intervals, the level of pain was rated with a 100-mm visual analog scale. Tissue-interface pressures were measured at the occiput, sacrum, and left heel.nnnRESULTSnMean pain on the visual analog scale was 9.7 mm at the end of the mattress period and 37.5 mm at the end of the no-mattress period (P = .0001). Although there were no significant differences in pain between the two groups at time 0, volunteers reported significantly more pain during the no-mattress period at 20 (P = .003), 40 (P = .0001), and 60 minutes (P = .0001). All 20 subjects reported that immobilization on the spine board with the mattress was much better (five-point scale) than that without the mattress. Interface pressure levels were significantly less in the mattress period than in the no-mattress period measured at occiput (P = .0001), sacrum (P = .0001), and heel (P = .0001).nnnCONCLUSIONnIn a simulated immobilization experiment, healthy volunteers reported significantly less pain during immobilization on a spine board with an interposed air mattress than during that on a spine board without a mattress. Tissue-interface pressures were significantly higher on spine boards without air mattresses. This and previous studies suggest that immobilization on rigid spine boards is painful and may produce tissue-interface pressure high enough to result in the development of pressure necrosis (bedsores). Emergency care providers should consider the use of interposed air mattresses to reduce the pain and potential tissue injury associated with immobilization on rigid spine boards.
Annals of Emergency Medicine | 1994
Michelle R Meengs; Beverly K. Giles; Carey D. Chisholm; William H. Cordell; David R Nelson
STUDY OBJECTIVEnPrevious studies, conducted mainly in ICUs, have shown low compliance with hand-washing recommendations, with failure rates approaching 60%. Hand washing in the emergency department has not been studied. We examined the frequency and duration of hand washing in one ED and the effects of three variables: level of training, type of patient contact (clean, dirty, or gloved), and years of staff clinical experience.nnnDESIGNnObservational.nnnSETTINGnED of an 1,100-bed tertiary referral, central city, private teaching hospital.nnnPARTICIPANTSnEmergency nurses, faculty, and resident physicians. Participants were informed that their activities were being monitored but were unaware of the exact nature of the study.nnnINTERVENTIONSnAn observer recorded the number of patient contacts and activities for each participant during three-hour observation periods. Activities were categorized as either clean or dirty according to a scale devised by Fulkerson. The use of gloves was noted and hand-washing technique and duration were recorded. A hand-washing break in technique was defined as failure to wash hands after a patient contact and before proceeding to another patient or activity.nnnRESULTSnEleven faculty, 11 resident physicians, and 13 emergency nurses were observed. Of 409 total contacts, 272 were clean, 46 were dirty, and 91 were gloved. Hand washing occurred after 32.3% of total contacts (SD, 2.31%). Nurses washed after 58.2% of 146 contacts (SD, 4.1%), residents after 18.6% of 129 contacts (SD, 3.4%), and faculty after 17.2% of 134 contacts (SD, 3.3%). Nurses had a significantly higher hand washing frequency than either faculty (P < .0001) or resident physicians (P < .0001). Hand washes occurred after 28.4% of 272 clean contacts (SD, 2.34%), which was significantly less (P < .0001) than 50.0% of 46 dirty contacts (SD, 7.4%) and 64.8% of 91 gloved contacts (SD, 5.0%). The number of years of clinical experience was not significantly related to hand-washing frequency (P = .82). Soap and water were used in 126 of the hand washes, and an alcohol preparation was used in the remaining six. The average duration of soap-and-water hand washes was 9.5 seconds.nnnCONCLUSIONnCompliance with hand washing recommendations was low in this ED. Nurses washed their hands significantly more often than either staff physicians or resident physicians, but the average hand-washing duration was less than recommended for all groups. Poor compliance in the ED may be due to the large number of patient contacts, simultaneous management of multiple patients, high illness acuity, and severe time constraints. Strategies for improving compliance with this fundamental method of infection control need to be explored because simple educational interventions have been unsuccessful in other health care settings.
Journal of the American College of Cardiology | 1997
James Trippi; Kamthorn S. Lee; Greg Kopp; David R Nelson; King G Yee; William H. Cordell
OBJECTIVESnThe practically and accuracy of dobutamine stress tele-echocardiography (DSTE) were assessed in patients presenting to the emergency department with chest pain.nnnBACKGROUNDnMany patients evaluated for chest pain in the emergency department (ED) are admitted to the hospital needlessly because of the difficulty in differentiating noncardiac chest pain from myocardial ischemia.nnnMETHODSnOne hundred sixty-three patients with no evidence of myocardial infarction on initial blood studies or the electrocardiogram who were recommended for hospital admission to rule out myocardial infarction or myocardial ischemia were enrolled in this four-phase study. Rest echocardiography was performed in the ED, and the images were transmitted to a cardiologist for interpretation. If the results were normal, DSTE was then administered by a trained nurse. In the first three phases, all patients were admitted for observation regardless of the results of DSTE. In the fourth phase, those having normal DSTE results were able to be released.nnnRESULTSnThe test was completed within an average of 5.4 h of presentation to the ED. The sensitivity and specificity of DSTE versus clinical and cardiac catheterization findings were 89.5% and 88.9%, respectively, with a negative predictive value for DSTE of 98.5%. Patients experienced frequent mild side effects (54.7%), but few (6.3%) caused the test to be discontinued prematurely. In phase 4 of the study, 72% of those slated for hospital admission because of cardiac risk factors and chest pain suggesting myocardial ischemia were discharged after normal DSTE results.nnnCONCLUSIONSnThe use of DSTE in the evaluation of patients presenting with chest pain may improve screening for those who can be safely released from the ED.
Journal of the American College of Cardiology | 1996
James Trippi; Kamthorn S. Lee; Greg Kopp; David R Nelson; Richard Kovacs
OBJECTIVESnThis study sought to assess the clinical utility of interpreting emergency echocardiograms after regular working hours through a telemedicine connection to on-call cardiologists.nnnBACKGROUNDnPhysician interpretation of emergency echocardiograms is often delayed during weekends, evenings or night hours. This delay places undue responsibility on less qualified personnel to interpret echocardiograms of vital importance.nnnMETHODSnDigital quad-screen cine-loop format was transmitted over standard telephone lines. Clinical data and conventional and telemedicine interpretations were collected prospectively for 187 emergent or semiemergent tele-echocardiograms after regular working hours.nnnRESULTSnIndications for the echocardiogram included assessment of left ventricular function, ischemia, pericardial effusion, valvular disease, heart donor status and arrhythmia. Three off-site echocardiographers received the standard echocardiogram and spectral, gray-scale and color flow Doppler images in cineloop format using a laptop computer. Laptop interpretation showed 19 technically limited studied, 153 abnormal studies and 54% with wall motion abnormalities. Overall mean agreement rate between telemedicine laptop interpretation and conventional workstation interpretation performed in blinded manner for serious disorders with classic echocardiographic findings (pulmonary hypertension, left ventricular thrombus, aortic dissection, severe valvular insufficiency and large pericardial effusion) was 99.0% (95% confidence interval [CI] 96% to 99%). For serious wall motion abnormalities, the agreement rate was 96.3% (95% CI 92% to 99%). The following mean times elapsed after completion of the echocardiogram: to laptop fax report, 2.14 (range 10 min to 8 h); to dictation of videotape, 11.74 h (p < 0.001); to transcription of videotape diction, 56.6 h (p < 0.0001).nnnCONCLUSIONSnAfter-hours emergency echocardiography telemedicine using a laptop computer is more rapid than scheduled conventional interpretation from a videotape workstation, yet diagnostic accuracy is comparable.
Annals of Emergency Medicine | 1996
William H. Cordell; Seth W Wright; Allan B. Wolfson; Beverly L Timerding; Thomas Maneatis; Ronald H Lewis; Lincoln Bynum; David R Nelson
STUDY OBJECTIVEnTo compare the analgesic efficacy and safety of IV ketorolac, the only nonsteroidal antiinflammatory drug indicated for parenteral use in acute pain in the United States, with IV meperidine and with a combination of the two agents in renal colic.nnnMETHODSnWe carried out a double-blind, randomized, multicenter clinical trial in the emergency departments of four urban tertiary care teaching hospitals. Our study subjects were 154 patients with suspected renal colic. Each subject received an initial IV dose of ketorolac 60 mg, meperidine 50 mg, or both supplemented as needed beyond 30 minutes with additional doses of meperidine.nnnRESULTSnThe main outcome measures were changes in pain-intensity and pain-relief scores, amount of supplemental meperidine required, end-of-study drug tolerability, and adverse events. Analyses of 106 subjects with confirmed renal colic indicated that ketorolac and the combination were significantly better than meperidine alone by all efficacy measures, including pain relief and time elapsed before the need for supplemental meperidine. By 30 minutes, 75% of the ketorolac group and 74% of the combination group had a 50% reduction in pain scores, compared with 23% of the meperidine group (P < .001). The ketorolac and combination groups did not differ significantly in any of the efficacy measures.nnnCONCLUSIONnIV ketorolac, alone or in combination with meperidine, was superior to IV meperidine alone in moderate and severe renal colic. Because many subjects in all three treatment groups received supplemental meperidine and because response to ketorolac alone cannot be predicted, clinicians may choose to initiate treatment with a ketorolac-meperidine combination.
Human Immunology | 1999
W. Page Faulk; Marlene L. Rose; Pier L. Meroni; Nicoletta Del Papa; Ronald J. Torry; Carlos A. Labarrere; Karen Busing; Samantha J Crisp; Michael J. Dunn; David R Nelson
BACKGROUNDnTransplant-induced coronary artery disease is a leading cause of graft failure in cardiac allograft recipients after the first year of transplantation, but there presently is no test to identify patients at high risk for developing the disease. Our research is focused on development of a predictive test to identify patients at high risk of developing the disease.nnnMETHODSnSixty-eight cardiac allograft recipients transplanted and followed at Methodist Hospital between 1982 and 1996 were studied. Serial annual angiograms were used to diagnose coronary artery disease, and serial endomyocardial biopsies were used to detect cellular infiltrates and microvascular disease. Biopsy-matched serum samples were used for cardiac troponin-T determinations as measures of myocardial damage, and serum antibodies to endothelial cells were determined by using flow cytometry, enzyme-linked immunosorbent assay and immunoblotting techniques. The endothelial antibody data were evaluated statistically for associations with angiographic changes, biopsy findings and biochemical evidence of myocardial damage.nnnFINDINGSnAntibodies to endothelial cells were identified by all three techniques, and significant associations were found for the amount of antibody identified by Western immunoblotting with histological rejection grades in biopsies, which were confirmed immunocytochemically as macrophages (p<0.01) and T lymphocytes (P = 0.03). These antibodies also associated significantly with vascular antithrombin depletion (p = 0.02), biochemical evidence of myocardial damage (p = 0.005) and subsequent development of coronary artery disease (p = 0.03).nnnINTERPRETATIONnThe significant association of anti-endothelial antibodies with cellular infiltrates, depletion of vascular antithrombin and myocardial damage suggests a role for antibody in the development of transplant-induced arteriopathy. The significant association of antiendothelial antibodies with the future development of coronary artery disease further suggests that assessment of these antibodies may provide a non-invasive test to predict the development of transplant-induced coronary artery disease.
Annals of Emergency Medicine | 1994
William H. Cordell; Todd A. Larson; James E. Lingeman; David R Nelson; John R. Woods; Linda B. Burns; Lawrence W. Klee
STUDY OBJECTIVESnTo develop a protocol for the blinded IV titration of morphine and to compare the analgesic efficacy and side effect profile of indomethacin suppositories versus IV morphine in the treatment of acute ureteral colic.nnnDESIGNnRandomized, double-blind, double-dummy, two-period crossover study.nnnSETTINGnEmergency department of a central-city, teaching hospital.nnnPARTICIPANTSnPatients 18 to 75 years of age with pain suggestive of ureteral colic. Exclusions included pregnancy, adverse reactions to the study drugs, chronic nonsteroidal anti-inflammatory drug (NSAID) therapy, or any pain medicine taken within four hours of ED admission.nnnINTERVENTIONSnPatients were randomized to one of two groups: indomethacin 100-mg rectal suppository or morphine by IV titration (5-mg loading dose and up to two additional 2.5-mg doses if needed). At the end of 30 minutes, if adequate pain relief had not been obtained, treatment was crossed over.nnnMEASUREMENTSnVerbal analog scale (initial pain) and visual analog pain relief scale.nnnMAIN RESULTSnSeventy-five patients were entered into the study. Only data from those patients with stone presence confirmed by IV pyelogram or stone passage were analyzed. Twenty-four could not be evaluated (23 who did not meet criteria for stone presence and one whose pain resolved spontaneously before study medications could be administered). Of the remaining 51 patients, 31 received indomethacin first and 20 received morphine first. Morphine recipients reported more pain relief at ten minutes (P = .02), but at 20 and 30 minutes, no significant difference (P = .17 and .74, respectively) existed between the two groups.nnnCONCLUSIONnIV morphine produced more rapid analgesia than rectally administered indomethacin. There were no significant differences in vital sign changes or number of side effects between the two treatment groups. This study is the first to compare an NSAID with morphine administered by IV titration, considered by many to be the gold standard for relief of acute, severe pain. Future studies could evaluate the simultaneous administration of an opioid combined with an NSAID or compare an IV titrated opioid with an IV NSAID.