Karl A. Sporer

Clinical course of γ-hydroxybutyrate overdose

STUDY OBJECTIVE To describe the clinical characteristics and course of γ-hydroxybutyrate (GHB) overdose. METHODS We assembled a retrospective series of all cases of GHB ingestion seen in an urban public-hospital emergency department and entered in a computerized database January 1993 through December 1996. From these cases we extracted demographic information, concurrent drug use, vital signs, Glasgow Coma Scale (GCS) score, laboratory values, and clinical course. RESULTS Sixty-one (69%) of the 88 patients were male. The mean age was 28 years. Thirty-four cases (39%) involved coingestion of ethanol, and 25 (28%) involved coingestion of another drug, most commonly amphetamines. Twenty-five cases (28%) had a GCS score of 3, and 28 (33%) had scores ranging from 4 through 8. The mean time to regained consciousness from initial presentation among nonintubated patients with an initial GCS of 13 or less was 146 minutes (range, 16-389). Twenty-two patients (31%) had an initial temperature of 35°C or less. Thirty-two (36%) had asymptomatic bradycardia; in 29 of these cases, the initial GCS score was 8 or less. Ten patients (11%) presented with hypotension (systolic blood pressure≤90 mm Hg); 6 of these patients also demonstrated concurrent bradycardia. Arterial blood gases were measured in 30 patients; 21 had a Pco2 of 45 or greater, with pH ranging from 7.24 to 7.34, consistent with mild acute respiratory acidosis. Twenty-six patients (30%) had an episode of emesis; in 22 of these cases, the initial GCS was 8 or less. CONCLUSION In our study population, patients who overdosed on GHB presented with a markedly decreased level of consciousness. Coingestion of ethanol or other drugs is common, as are bradycardia, hypothermia, respiratory acidosis, and emesis. Hypotension occurs occasionally. Patients typically regain consciousness spontaneously within 5 hours of the ingestion. [Chin RL, Sporer KA, Cullison B, Dyer JE, Wu TD: Clinical course of γ-hydroxybutyrate overdose. Ann Emerg Med June 1998;31: 716-722.].

Acetaminophen and salicylate serum levels in patients with suicidal ingestion or altered mental status

Is universal screening of acetaminophen (APAP) and salicylate (SAL) necessary in patients with a suicidal ingestion or an altered mental status and suspected ingestion? This descriptive, retrospective chart review in an emergency department in a large urban county hospital examined all patients who presented with a history of suicidal ingestion or an altered mental status with a strong suspicion of ingestion from January 1992 through October 1993. APAP and SAL serum levels were measured in 1,820 patients, and charts of patients with APAP serum levels of > 1 microgram/mL or SAL serum levels of > 1 mg/dL were reviewed. The patients history of ingesting APAP or SAL was recorded, as well as the clinicians interpretation of that level. Sixteen charts were not available. APAP levels of > 1 microgram/mL were found in 175 (9.6%) patients, 120 (6.5%) of whom were APAP history-positive and 55 (3%) APAP history-negative. None of the APAP history-negative group required therapy with N-acetylcysteine. Eight (0.3%) of the APAP history-negative group had potentially toxic levels of > 50 micrograms/mL. SAL levels of > 1 mg/dL were found in 155 (8.5%) patients, 44 (2.5%) of whom were SAL history-positive and 111 (6%) SAL history-negative. Three patients were SAL history-negative but had a significant chronic SAL intoxication. All these patients presented with an altered mental status and had an anion gap of > 20 mEq/L. Universal screening found that 0.3% of suicidal ingestions had a potentially toxic APAP intoxication not suggested by history. This incidence of infrequent but potentially life: threatening overdose should prompt clinicians to screen all of their patients with a suspected ingestion. Salicylate screening found that 0.16% of suicidal ingestions had a toxic SAL intoxication not suggested by history, although such intoxication should be suggested by an elevated anion gap and an altered mental status. Since this less severe intoxication is less frequent and usually suggested by commonly obtained laboratory data, universal screening is not indicated, but a more selective approach to screening could be taken.

Clinical Course of Crack Cocaine Body Stuffers

STUDY OBJECTIVE To describe the clinical course of a cohort of patients presenting to the emergency department with acute crack cocaine body-stuffer syndrome. METHODS We conducted a retrospective cohort study in the ED of a county hospital with 75,000 visits per year. Our study cohort comprised all patients who presented between January 1993 and April 1995 and who met the definition of a crack cocaine body stuffer. We defined a crack cocaine body stuffer as anyone who admitted to or was strongly suspected of ingesting crack cocaine as a means of escaping detection by authorities, not for recreational purposes or as a means of transporting the drug across borders. RESULTS We identified 98 cases; most such patients were brought to the ED by law enforcement agents. Most were male and younger than 30 years. Self-report by patients indicated that the amount of crack cocaine ingested ranged from 1 to more than 15 rocks. Most commonly the drug was unwrapped (28%) or wrapped in a plastic sandwich bag (29%). Generalized seizures developed in 4% of the patients; in all these patients seizures occurred within 2 hours of ingestion. In no patient did dysrhythmias develop. Many patients had minor signs of cocaine intoxication: 54% were tachycardic, 23% were hypertensive, 22% were agitated, and 19% required sedation. CONCLUSION Mild cocaine intoxication is common in crack cocaine body stuffers, with seizures occurring within 2 hours of ingestion in a small percentage of patients.

Validation of Low-Acuity Emergency Medical Services Dispatch Codes

Background. Computer-aided dispatch systems are used to assess the severity of a 9-1-1 callers complaint andthen assign an appropriate level of emergency medical services (EMS) response. Objective. To evaluate a group of low-acuity codes (defined as requiring advanced life support [ALS] intervention in fewer than 10% of cases) that has been derived andvalidated in one community. Methods. All of the 9-1-1 medical calls assigned to these predetermined emergency medical dispatch codes between January 1, 2004, andJuly 1, 2004, were analyzed. ALS care was defined as receiving one or more of the following: pulse oximetry measurement, blood glucose measurement, cardiac defibrillation, administration of any medication, airway maneuvers, or the placement of an intravenous (IV) catheter. A more restrictive definition of ALS care (use of IV fluid bolus, medication administration, intubation, or defibrillation) was also calculated. Results. A total of 1,799 calls were assigned low-acuity dispatch codes, and1,597 met inclusion criteria. None of the 26 dispatch codes were found to be low-acuity by the study definition. Fifty-six percent of these patients received ALS care. Placement of an IV-catheter was the ALS intervention used most frequently (45% of cases), followed by pulse oximetry measurement (32%), glucose measurement (22%), medication administration (11%), intubation (0.13%), anddefibrillation (0%). The medication administered most frequent was morphine. When using the more restrictive definition of acuity, patients in 19 of the 28 categories received ALS intervention less than 10% of the time. Patients in the other seven categories were considered high-acuity 13% to 36% of the time. Conclusion. Dispatch codes that had previously been determined to be low-acuity were found not to be so in this community. The variation in clinical practice is likely explained by a more precautionary approach to care in this EMS system andthe increased use of analgesics. This study demonstrates the need to define the optimal subset of prehospital patients who would benefit from these treatments. Key words: ambulances; cardiopulmonary resuscitation; emergencies; emergency medical service communication systems; emergency medical services; retrospective studies; risk assessment; triage; acuity; wounds andinjuries; dispatch codes.

Massive ingestion of sustained-release verapamil with a concretion and bowel infarction

Gastric concretions secondary to a drug overdose are uncommon but potentially fatal if not recognized and treated. They may continue to release drug into the stomach for hours or days after the ingestion, complicating diagnosis and treatment. We describe the case of a man with the previously unreported association of bowel infarction with a verapamil ingestion and concretion. This case illustrates the need for a heightened awareness of this potential complication.

The Ability of Emergency Medical Dispatch Codes of Medical Complaints to Predict ALS Prehospital Interventions

Objective. The Medical Priority Dispatch System (MPDS) is an emergency medical dispatch (EMD) system that is commonly used to triage 9-1-1 calls andoptimize paramedic andEMT dispatch. The objective of this study was to determine the sensitivity, specificity, andpositive andnegative predictive values of selected MPDS dispatch codes to predict the need for ALS medication or procedures. Methods. Patients with selected MPDS codes between November 1, 2003, andOctober 31, 2005, from a suburban California county were matched with their electronic patient care record. The records of all transported patients were queried for prehospital interventions andmatched to their MPDS classification [Basic Life Support (BLS) versus Advanced Life Support (ALS)]. Patients who received prehospital interventions or medications were considered ALS Intervention. With true positive = ALS by MPDS + ALS Intervention, true negative = BLS by MPDS + BLS Interventions, false positive = ALS by MPDS + BLS Interventions, andfalse negative = BLS by MPDS + ALS Interventions, the screening performance of the San Mateo County EMD system was determined for selected complaint categories (abdominal pain, breathing problems chest pain, sick person, seizures, andunconscious/fainting). Results. There were a total of 64,647 medical calls, and42,651 went through the EMD process; 31,187 went through the EMD process andwere transported; 22,243of these were matched to a patient care record. The sensitivity andspecificity with 95% confidence intervals in () were as follows: all EMD calls 84 (83–85), 36 (35–36); abdominal pain, 53 (41–65), 47 (43–51); chest pain 99 (99–100), 2 (1–3); seizure 83 (77–88), 20 (17–23), sick 59 (53–64), 51 (49–54), andunconscious/fainting 99 (98–100), 2 (2–3). Conclusion. In our EMS system, MPDS coding for all medical calls had high sensitivity andlow specificity for the prediction of calls that required ALS intervention. Chest pain andunconscious/fainting calls were screened with very high sensitivity but very low specificity.

Randomized trial of drug abuse treatment-linkage strategies.

A clinical trial contrasted 2 interventions designed to link opioid-dependent hospital patients to drug abuse treatment. The 126 out-of-treatment participants were randomly assigned to (a) case management, (b) voucher for free methadone maintenance treatment (MMT), (c) case management plus voucher, or (d) usual care. Services were provided for 6 months. MMT enrollment at 3 months was 47% (case management), 89% (voucher), 93% (case management plus voucher), and 11% (usual care); at 6 months enrollment was 48%, 68%, 79%, and 21%, respectively. Case management and vouchers can be valuable in health settings to link substance abusers with medical problems to drug abuse treatment.

Can Emergency Medical Dispatch Codes Predict Prehospital Interventions for Common 9-1-1 Call Types?

Objective. The Medical Priority Dispatch System is an emergency medical dispatch (EMD) system that is widely used to categorize 9-1-1 calls andoptimize resource allocation. This study evaluates the ability of EMD andnon-EMD codes (calls not processed by EMD) to predict prehospital use of medications andprocedures. Methods. All transported prehospital patients placed in an EMD or non-EMD category that exceeded 500 total calls from January 1, 2004, to December 31, 2006, in a suburban California county were matched with their prehospital electronic patient care record. These records (N = 69,541) were queried for the following prehospital interventions: basic life support (BLS) care only, intravenous line placement only, medication given, andprocedures. Advanced life support (ALS) interventions were defined as the administration of a medications or a procedure. The numbers of medications andprocedures that were performed on patients in each EMD code were measured. Results. Thirty-one of 141 EMD andnon-EMD codes met inclusion criteria andcomprised 73% of all calls during the study period. Non-EMD codes accounted for 48% of all calls in this study. Patients with shortness of breath, chest pain, diabetic problems, andaltered mental status received the most medications. High rates of medication administration were also seen in the following codes: 17A (fall, 27%), 17B (fall, 14%), EMDX (unable to complete EMD process, 22%), MED (medical aid requested—details to follow, 26%), andMED3 (medical aid requested by police—code 3, 18%). Procedures were performed on only 0.9% of all calls, of which 75% were related to advanced airways. Higher rates of ALS interventions in higher-acuity categories (Alpha, Bravo, etc.) were seen in a number of EMD categories, including seizure, laceration/hemorrhage, sick, andtraffic accident, but not seen in many categories, including abdominal pain, falls, andchest pain. Conclusions. This study demonstrated only a modest ability of the EMD system to predict which patients would require ALS intervention. There were limited differences noted in the ALS rates between the different codes (Alpha, Bravo, etc.) in the same complaint category, bringing into question the utility of the multiple subgroups. Non-EMD codes made up a large portion of calls (48%) andshould be included in future studies.

Do Medications Affect Vital Signs in the Prehospital Treatment of Acute Decompensated Heart Failure

Introduction. Prehospital treatment of patients with acute decompensated heart failure (ADHF) has been shown to decrease mortality andmorbidity. Vital sign changes have been proposed as clinical endpoints in the evaluation of prehospital treatment for this condition. Objective. To examine the effect of prehospital treatments on vital signs among patients with ADHF. Methods. Records of an urban emergency medical services system from September 1, 2002, through September 1, 2003, were queried for patients who had a paramedic impression of shortness of breath or respiratory distress andhad received nitroglycerin and/or furosemide. Demographics, initial andrepeat vital signs (blood pressure, heart rate, respiratory rate, andoxygen saturation), andmedications anddoses were collected. Results. Three hundred nineteen patients were included; the average age was 77 (±12) years and47% were male. Treatments administered to these patients included nitroglycerin, 296 (93%); furosemide, 194 (61%); albuterol, 189 (59%); aspirin, 57 (18%); morphine, 20 (6%); andprehospital intubation, 15 (5%). Patients were initially hypertensive [mean ± standard deviation of systolic blood pressure (SBP) was 167 ±37 mm Hg], tachycardic (heart rate 106 ± 24 beats/min), tachypneic (respiratory rate 33 ± 7 breaths/min), andhypoxic (pulse oximetry 88% ± 9.5%). After treatment, mean changes included decreases (95% confidence interval) in (SBP), −10.6 mm Hg (−14.1 to −7.1), heart rate, −2.3 beats/min (−4.0 to −0.7), andrespiratory rate, −3.0 (−3.6 to −2.3), andan increase in oxygen saturation, +8.2 (7.1 to 9.3). Changes in blood pressure andoxygen saturation after treatment correlated with initial values. There was no independent association of either nitroglycerin, furosemide, albuterol, or morphine with improvement in vital signs. Conclusion. Prehospital patients with ADHF are a heterogeneous group of patients with significant variability in vital signs. The change in systolic blood pressure or oxygen saturation after treatment depends greatly on the patients starting point. There was no association of either nitroglycerin or other medications with the improvement in vital signs.

Does Emergency Medical Dispatch Priority Predict Delphi Process-Derived Levels of Prehospital Intervention?

OBJECTIVE The Medical Priority Dispatch System (MPDS) is an emergency medical dispatch system widely used to prioritize 9-1-1 calls and optimize resource allocation. This study evaluates whether the assigned priority predicts a Delphi process-derived level of prehospital intervention in each emergency medical dispatch category. METHODS All patients given a MPDS priority in a suburban California county from 2004-2006 were included. A Delphi process of emergency medical services (EMS) professionals in another system developed the following categories of prehospital treatment representing increasing acuity, which were adapted for this study: advanced life support (ALS) intervention, ALS-Stat, and ALS-Critical. The sensitivities and specificities of MPDS priority for level of prehospital intervention were determined for each MPDS category. Likelihood ratios of low and high priority dispatch codes for the level of prehospital intervention also were calculated for each MPDS category. RESULTS A total of 65,268 patients met inclusion criteria, representing 61% of EMS calls during the study period. The overall sensitivities of high-priority dispatch codes for ALS, ALS-Stat, and ALS-Critical interventions were 83% (95% confidence interval 83-84%), 83% (82-84%), and 94% (92-96%). Overall specificities were: ALS, 32% (31-32%); ALS-Stat, 31% (30-31%); and ALS-Critical 28% (28-29%). Compared to calls assigned to a low priority, calls with high-priority dispatch codes were more likely to receive ALS interventions by 22%, ALS-Stat by 20%, and ALS-Critical by 32%. A low priority dispatch code decreased the likelihood of ALS interventions by 48%, ALS-Stat by 45%, and ALS-Critical by 80%. Among high-priority dispatch codes, the rates of interventions were: ALS 26%, ALS-Stat 22%, and ALS-Critical 1.5%, all of which were significantly greater than low-priority calls (p<0.05) [ALS 13%, ALS-Stat 11%, and ALS-Critical 0.2%]. Major MPDS were categories with high sensitivities (>95%) for ALS interventions included breathing problems, cardiac or respiratory arrest/death, chest pain, stroke, and unconscious/fainting; these categories had an average specificity of 3%. Medical Priority Dispatch System categories such as back pain, unknown problem, and traumatic injury had sensitivities for ALS interventions<15%. CONCLUSIONS The MPDS is moderately sensitive for the Delphi process derived ALS, ALS-Stat, and ALS-Critical intervention levels, but nonspecific. A low MPDS priority is predictive of no prehospital intervention. A high priority, however, is of little predictive value for ALS, ALS-Stat, or ALS-Critical interventions.