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Developing a clinical model to predict C-spine injury in child trauma victims
ABSTRACTS
significant difference between the two groups in pH prior to CPR (6.99 vs 7.06 at -5; 6.97 vs 7.20 at -1). There were, however, statistically significant differences in pH in these two groups throughout CPR. The pH in Grp 2 was initially alkalotic (7.65 at +3 min), but it then approached the physiologic range and remained there until 30 min postarrest, when acidosis was noted (pH, 7.24). This is in sharp contrast to Grp 0, in which acidosis was present from the onset of resuscitation and worsened throughout (pH, 7.20 at +3; 6.80 at +40). In this model, the current regimen of 2 mEq/kg of NaHCO3 initially, followed by subsequent 1-mEq/kg doses, may not be optimal because it produces an initial alkalosis. A dosage schedule of 1 mEq/kg initially and subsequently might correct the acidosis without causing an initial alkalosis, and it might maintain pH in the physiologic range.
3
Diagnosis of Group A Strep Pharyngitis in the Emergency Department in Ten Minutes
University School of Medicine, El Paso, Texas
A 10-minute, rapid test for diagnosing Group A Strep pharyngitis was evaluated using positive throat cultures as the marker for disease. Patients presenting to the ED in a 2-month period with a complaint of sore throat were entered in the study (147 patients). Patients were examined, and a clinical impression of disease was made. A single throat swab was used for culture and the rapid test. Patients were treated initially on the basis of clinical judgment before laboratory tests were known. The rapid test had a sensitivity of 77% and a specificity of 93%. Clinical judgment had a sensitivity of 69% and a specificity of 57%. The rapid test was significantly better than clinical judgment alone in determining the presence of disease (P < .05): The predictive values of the positive and the negative for the rapid test were 79% and 93%, respectively. The predictive values of the positive and the negative for clinical judgment were 50% and 86%, respectively. In the ED setting, where adequate follow-up is difficult (14% in this study), the rapid test can identify more accurately those who need therapy w h e n c o m p a r e d to clinical judgment alone, and it will obviate the need for throat cultures.
Developing a Clinical Model to Predict C-Spine Injury in Child Trauma Victims
D Jaffe, H Binns, MA Radkowski, M Barthel/Division of General and Emergency Pediatrics, The Children's Memorial Hospital, Chicago
The child with head or multiple injuries presents difficulties in early emergency cervical spine (C-spine) management. By analogy to the adult experience, neck immobilization and C-spine radiography are routine. Yet neck immobilization in struggling children can be technically difficult and obstructive to other essential evaluations. To define a subset of child trauma victims for whom emergency C-spine immobilization and radiography may be unnecessary, we performed a retrospective study of all traumatized children who obtained C-spine radiographs in our children's hospital from September 1983 to September 1984. We also included all cases of C-spine injury from 1973 to 1983. All radiographs were reviewed by a pediatric radiologist, and patients with inadequate studies were excluded. Clinical data included demographics, location and circumstances of injury, initial physical examination, and the Abbreviated Injury Scale (AIS). Data were analyzed using chi-square and contingency coefficients (CC). The study sample included 139 children 0-16 years old. Seventeen had spine or cord injuries, and 122 had normal C-spines. Variables strongly associated with C-spine injuries include the following: complaint of neck pain (P < .001} or limitation of neck motion (P < .005); neck tenderness (P < .001); abnormalities in reflexes (P < .005), strength (P < .0I) or sensation (P < .01); loss of consciousness (P < .05}; AIS score (P < .01); and injury in a motor
184/504
5
Caustic Ingestions: An In Vitro Study of the Effects of Buffer, Neutralization, and Dilution
KI Maul~, AP Osmand, CD Maull/University of Tennessee
D DuBois, VG Ray, B Nelson / Department of Surgery, Texas Tech
4
vehicle (P < .0I). Variables approaching significance include presence of life-threatening problems (CC = .14); abnormal mental status (CC = .14); arrival with neck immobilized (CC = .17); and torticollis (CC = .13). In our sample of 17 children with spine injuries, we could select 14 using the strong variables, and 16 by adding the weaker variables. These variables can be used to develop a log linear or discriminant model that may permit the safe exclusion of unnecessary C-spine films presently obtained for child trauma victims.
Memorial Research Center and Hospital, Knoxville
In order to determine relative changes in pH and temperature of solutions of commonly ingested liquid caustics (liquid Drano - - alkali; toilet bowl cleaner--acid) treated by addition of buffer (antacid), diluent (water), or neutralizing agent (weak acid), equal i n c r e m e n t s of each substance were added to 50 cc of liquid caustic. A Fisher Versamix constant agitator assured immediate mixing. A Forma scientific LCD digital thermometer and a Beckman Expandomatic IV pH meter were used for instantaneous temperature and pH readings. Results are shown in Tables 1 and 2. Caustic - - Alkali (No OH) Volume Added Acetic Acid 80 cc Water 800 cc Caustic - - Acid (HCl) Volume Added Magnesium 200 cc aluminum hydroxide Water 800 cc
Temp C° + 1.2° +0.5
~pH - 4.85 - 1.2
Neutralization Yes No
Temp C° +6.1
/XpH +2.17
Neutralization No
0
+ 0.5
No
It is concluded that dilution as a first-aid measure is ineffective in the management of caustic ingestions because even large volumes of diluent do not appreciably change the pH of the caustic. Neutralization requires relatively small amounts of solution, causes minimal heat of reaction, and promptly changes the pH toward neutral. Buffer solutions should be avoided because they cause a rapid release of heat (? heat of formation) without an immediate change in pH of solution. In vivo studies are needed to confirm the relative roles of pH extremes and heat in the genesis of tissue injury.
6
Comparative Effectiveness of Cathartics Used with Activated Charcoal
EP Krenzelok, R Keller, RD Stewart / School of Medicine, University of Pittsburgh; Center for Emergency Medicine of Western Pennsylvania, Pittsburgh
Activated charcoal and a cathartic are routinely used in the management of many poisoning emergencies. The adsorption of toxins by activated charcoal is not an irreversible process. Therefore, expeditious catharsis of the activated charcoal/toxin complex is critical. This research project was designed to determine which cathartic would produce the most rapid elimination of activated charcoal. In a crossover design, 23 consenting adult human volunteers consumed activated charcoal (50 g) and each of the following cathartics - - magnesium citrate, magnesium sul-
Annals of Emergency Medicine
14:5 May 1985
significant difference between the two groups in pH prior to CPR (6.99 vs 7.06 at -5; 6.97 vs 7.20 at -1). There were, however, statistically significant differences in pH in these two groups throughout CPR. The pH in Grp 2 was initially alkalotic (7.65 at +3 min), but it then approached the physiologic range and remained there until 30 min postarrest, when acidosis was noted (pH, 7.24). This is in sharp contrast to Grp 0, in which acidosis was present from the onset of resuscitation and worsened throughout (pH, 7.20 at +3; 6.80 at +40). In this model, the current regimen of 2 mEq/kg of NaHCO3 initially, followed by subsequent 1-mEq/kg doses, may not be optimal because it produces an initial alkalosis. A dosage schedule of 1 mEq/kg initially and subsequently might correct the acidosis without causing an initial alkalosis, and it might maintain pH in the physiologic range.
3
Diagnosis of Group A Strep Pharyngitis in the Emergency Department in Ten Minutes
University School of Medicine, El Paso, Texas
A 10-minute, rapid test for diagnosing Group A Strep pharyngitis was evaluated using positive throat cultures as the marker for disease. Patients presenting to the ED in a 2-month period with a complaint of sore throat were entered in the study (147 patients). Patients were examined, and a clinical impression of disease was made. A single throat swab was used for culture and the rapid test. Patients were treated initially on the basis of clinical judgment before laboratory tests were known. The rapid test had a sensitivity of 77% and a specificity of 93%. Clinical judgment had a sensitivity of 69% and a specificity of 57%. The rapid test was significantly better than clinical judgment alone in determining the presence of disease (P < .05): The predictive values of the positive and the negative for the rapid test were 79% and 93%, respectively. The predictive values of the positive and the negative for clinical judgment were 50% and 86%, respectively. In the ED setting, where adequate follow-up is difficult (14% in this study), the rapid test can identify more accurately those who need therapy w h e n c o m p a r e d to clinical judgment alone, and it will obviate the need for throat cultures.
Developing a Clinical Model to Predict C-Spine Injury in Child Trauma Victims
D Jaffe, H Binns, MA Radkowski, M Barthel/Division of General and Emergency Pediatrics, The Children's Memorial Hospital, Chicago
The child with head or multiple injuries presents difficulties in early emergency cervical spine (C-spine) management. By analogy to the adult experience, neck immobilization and C-spine radiography are routine. Yet neck immobilization in struggling children can be technically difficult and obstructive to other essential evaluations. To define a subset of child trauma victims for whom emergency C-spine immobilization and radiography may be unnecessary, we performed a retrospective study of all traumatized children who obtained C-spine radiographs in our children's hospital from September 1983 to September 1984. We also included all cases of C-spine injury from 1973 to 1983. All radiographs were reviewed by a pediatric radiologist, and patients with inadequate studies were excluded. Clinical data included demographics, location and circumstances of injury, initial physical examination, and the Abbreviated Injury Scale (AIS). Data were analyzed using chi-square and contingency coefficients (CC). The study sample included 139 children 0-16 years old. Seventeen had spine or cord injuries, and 122 had normal C-spines. Variables strongly associated with C-spine injuries include the following: complaint of neck pain (P < .001} or limitation of neck motion (P < .005); neck tenderness (P < .001); abnormalities in reflexes (P < .005), strength (P < .0I) or sensation (P < .01); loss of consciousness (P < .05}; AIS score (P < .01); and injury in a motor
184/504
5
Caustic Ingestions: An In Vitro Study of the Effects of Buffer, Neutralization, and Dilution
KI Maul~, AP Osmand, CD Maull/University of Tennessee
D DuBois, VG Ray, B Nelson / Department of Surgery, Texas Tech
4
vehicle (P < .0I). Variables approaching significance include presence of life-threatening problems (CC = .14); abnormal mental status (CC = .14); arrival with neck immobilized (CC = .17); and torticollis (CC = .13). In our sample of 17 children with spine injuries, we could select 14 using the strong variables, and 16 by adding the weaker variables. These variables can be used to develop a log linear or discriminant model that may permit the safe exclusion of unnecessary C-spine films presently obtained for child trauma victims.
Memorial Research Center and Hospital, Knoxville
In order to determine relative changes in pH and temperature of solutions of commonly ingested liquid caustics (liquid Drano - - alkali; toilet bowl cleaner--acid) treated by addition of buffer (antacid), diluent (water), or neutralizing agent (weak acid), equal i n c r e m e n t s of each substance were added to 50 cc of liquid caustic. A Fisher Versamix constant agitator assured immediate mixing. A Forma scientific LCD digital thermometer and a Beckman Expandomatic IV pH meter were used for instantaneous temperature and pH readings. Results are shown in Tables 1 and 2. Caustic - - Alkali (No OH) Volume Added Acetic Acid 80 cc Water 800 cc Caustic - - Acid (HCl) Volume Added Magnesium 200 cc aluminum hydroxide Water 800 cc
Temp C° + 1.2° +0.5
~pH - 4.85 - 1.2
Neutralization Yes No
Temp C° +6.1
/XpH +2.17
Neutralization No
0
+ 0.5
No
It is concluded that dilution as a first-aid measure is ineffective in the management of caustic ingestions because even large volumes of diluent do not appreciably change the pH of the caustic. Neutralization requires relatively small amounts of solution, causes minimal heat of reaction, and promptly changes the pH toward neutral. Buffer solutions should be avoided because they cause a rapid release of heat (? heat of formation) without an immediate change in pH of solution. In vivo studies are needed to confirm the relative roles of pH extremes and heat in the genesis of tissue injury.
6
Comparative Effectiveness of Cathartics Used with Activated Charcoal
EP Krenzelok, R Keller, RD Stewart / School of Medicine, University of Pittsburgh; Center for Emergency Medicine of Western Pennsylvania, Pittsburgh
Activated charcoal and a cathartic are routinely used in the management of many poisoning emergencies. The adsorption of toxins by activated charcoal is not an irreversible process. Therefore, expeditious catharsis of the activated charcoal/toxin complex is critical. This research project was designed to determine which cathartic would produce the most rapid elimination of activated charcoal. In a crossover design, 23 consenting adult human volunteers consumed activated charcoal (50 g) and each of the following cathartics - - magnesium citrate, magnesium sul-
Annals of Emergency Medicine
14:5 May 1985