Air embolism following peripheral intravenous access.

Air embolism is a rare, often misdiagnosed, potentially fatal condition. It is most frequently associated with invasive vascular procedures and mechanical ventilation. Air emboli developing from peripheral intravenous lines are uncommon. We present a case of symptomatic venous air embolism likely arising from peripheral intravenous access gained during an interventional pain procedure. This case highlights the need to consider air embolism in the differential diagnoses of patients presenting with neurological symptoms following vascular interventions.

The clinical presentation and impact of diagnostic delays on emergency department patients with spinal epidural abscess.

Previous reports have recommended the use of a "classic triad" of fever, spine pain, and neurologic deficits to diagnose spinal epidural abscess (SEA); however, the prognosis for complete recovery is poor once these deficits are present. This retrospective case-control study investigates the impact of diagnostic delays on outcome and explores the use of risk factor screening for early identification of SEA in a population of ED patients. Inpatients with a discharge diagnosis of SEA and a related ED visit before the admission were identified over a 10-year time period. In addition, a pool of ED patients presenting with a chief complaint of spine pain was generated; controls were hand-matched 2:1 to each SEA patient based on age and gender. Data regarding demographics, presence of risk factors, physical examination findings, laboratory and radiographic results, and clinical outcome were abstracted from medical records and entered into a database for further analysis. Patients with SEA were compared to matched controls with regard to the prevalence of risk factors and the "classic triad." We also explored the impact on outcome of diagnostic delays, defined as either: 1) multiple ED visits before diagnosis, or 2) admission without a diagnosis of SEA and >24 h to a definitive study. A total of 63 SEA patients were hand-matched to 126 controls with spine pain. Diagnostic delays were present in 75% of SEA patients. Residual motor weakness was present in 45% of these patients vs. only 13% of patients without diagnostic delays (odds ratio 5.65, 95% C.I. 1.15-27.71, p < 0.05). The "classic triad" of spine pain, fever, and neurologic abnormalities was present in 13% of SEA patients and 1% of controls during the initial visit (p < 0.01); one or more risk factors were present in 98% of SEA patients and 21% of controls (p < 0.01). The erythrocyte sedimentation rate (ESR) was more sensitive and specific than total white blood cell (WBC) count as a screen for SEA. In conclusion, diagnostic delays are common in patients with SEA, often leading to irreversible neurologic deficits. The use of risk factor assessment is more sensitive than the use of the classic diagnostic triad to screen ED patients with spine pain for SEA. The ESR may be a useful screening test before magnetic resonance imaging in selected patients.

Prevalence of autonomic signs and symptoms in antimuscarinic drug poisonings.

Classically described antimuscarinic poisoning signs and symptoms include mydriasis, decreased secretions, ileus, urinary retention, hyperthermia, tachycardia, and altered mental status. These features may be used clinically to assist in the diagnosis of patients with unknown poisonings. We sought to analyze the prevalence of antimuscarinic physical examination findings in evaluating patients presenting with acute poisoning from antimuscarinic agents. We conducted a retrospective, medical record review at two urban tertiary care teaching hospitals. The study population consisted of patients presenting to the Emergency Department with a diagnosis of acute poisoning secondary to medications with known antimuscarinic side effects during a 78-month period between January 1994 and July 2001. Cases were excluded for incomplete medical records or unreliable histories of ingestion, and when concomitant ethanol intoxication was present on laboratory analysis. Clinical information obtained from each patient included vital signs, pupillary size, electrocardiogram abnormalities, the presence of mucous membrane and axillary secretions, initial urine output after bladder catheterization, quality of bowel sounds, mental status changes, the occurrence of seizures and coma, need for orotracheal intubation, and time required for clinical resolution. Diagnostic and therapeutic information including laboratory tests, administration of sodium bicarbonate, and usage of physostigmine was also collected. We identified a total of 345 cases, 213 of which met inclusion criteria. Of these cases, the most common documented findings included decreased secretions in 75.1%, tachycardia in 68.1%, confusion in 49.3%, drowsiness in 48.2%, and hypoactive or absent bowel sounds in 44.6%. Combining signs and symptoms to predict this toxic syndrome was not very reliable. Tachycardia, decreased oral or axillary secretions, and mydriasis proved to be the most predictive trio of clinical signs, but were found in only 28.2% of cases. At least one of these three signs was documented in 94% of our patients. The combination of tachycardia and decreased secretions was the most common pair of findings, recorded in 55.4% of cases. We conclude that the clinical presentation of antimuscarinic syndrome is variable.