Steven B. Karch

Field intubation of trauma patients: complications, indications, and outcomes.

Neither the success nor the complication rate for field intubation of trauma patients is known with any certainty. A retrospective audit of 94 severely injured patients who required field intubation was undertaken. Fifty percent (13 of 26) of survivors and 67% (37 of 71) of nonsurvivors were successfully intubated in the field (not significant). Mechanism of injury was similar in both groups, but survivors were younger (27 v 60 years, P= .049) and less critically injured, as reflected by their Injury Severity Scale scores, their Trauma Scores, and their field Glasgow Coma Scale scores (22.1 v 30.8, P = .0035; 7.7 v 4.2, P < .0002; and 6.3 v 3.3, P < .0001). When compared with previously published studies of medical patients with cardiac arrest, the success rate was lower in our trauma patients. When compared with patients having similar injuries intubated at the trauma center, field intubation was three times more likely to be associated with the development of nosocomial pneumonia than was hospital intubation.

Coronary artery spasm induced by intravenous epinephrine overdose

A 27-year-old man was accidentally given 2 mg intravenous epinephrine instead of 2 mg naloxone. He immediately developed chest pain, nausea, and diaphoresis. An ECG taken shortly after the epinephrine administration showed widespread ischemia. Forty-five minutes later the tracing still showed an early repolarization pattern, but ST elevation was less marked and the patient was asymptomatic. Serum potassium was 3.2 mEq/L and serum catecholamines, drawn approximately 20 minutes after the epinephrine administration, were 10 times normal (dopamine, 173 ng/L; epinephrine, 1,628 ng/L; norepinephrine, 1,972 ng/L). There are seven other reports of intravenous epinephrine overdose in the English literature. Two of the previously reported cases had 12-lead ECGs within the first hour. In both there was evidence of transient ischemia similar to that observed in this case. Most of the patients had symptoms consistent with angina, and several developed pulmonary edema. These findings suggest that, in humans, large intravenous doses of epinephrine are likely to produce coronary artery spasm and may decrease coronary artery perfusion.

Cardiac arrest in cocaine users

The Incas attributed magical powers to the coca leaf and limited its use to royalty. 1 Chewing the leaf was said to impart strength, endurance, and the occasional religious vision. Thousands of years later, magical powers are still attributed to cocaine. Today it is frequently certified as a cause of death, even when it is present in barely detectable concentrations. Since it is almost inconceivable that any alkaloid, in concentrations of just one or two parts per billion, could cause cardiac arrest, or any other symptoms for that matter, either the coroners are wrong, or the Incas were right, and cocaine does have magical properties! Or, perhaps, we have been approaching the problem incorrectly. Very recently, the underlying mechanisms in cocainerelated sudden death have become much clearer. During 1994, researchers from a number of different laboratories reported observations that, taken together, may explain what cocaine does to the heart and go a long way toward explaining what causes cardiac arrest in cocaine users. Those developments will be reviewed here. Whether this knowledge will lead to improved outcomes remains to be seen, but at least physicians now have a better idea of just what disorder they are treating. According to tile last Drug Abuse Warning Network (DAWN) survey, there were 3,465 cocaine-associated deaths in 1993, nearly twice as many deaths as were reported for heroin during that same time period. 2 The real number of deaths related to cocaine use is much greater. For example, deaths of cocaine users who die several days after admission to the hospital will not be captured using DAWN methodology. 3 The cause of death in many of these cases remains obscure. After eliminating a small percentage of deaths due to stroke and subarachnoid hemorrhage, and a somewhat larger number of cases due to hyperthermia and agitated delirium, the remaining cases fall into two categories: those where death is clearly the result of myocardial infarction, and those where it is not. Most of the deaths fall into the second category. Myocardial infarction in cocaine users is now so common that new cases are no longer considered reportable. Several different mechanisms may be responsible for infarction. Autopsies of patients with cocaine-related infarcts disclose fixed atherosclerotic lesions more than half the time, 6,v but even in the absence of fixed lesions, cocaines ability to cause coronary artery vasospasm is well known. 4,5 Explaining the deaths of cocaine users with significant fixed lesions

Pathology of the lung in near-drowning

In order to study the initial pathological changes that occur in drowning, the authors developed an experimental model that closely simulates the actual changes in the nearly drowned patient. Adult male rabbits were anesthetized and intubated, and 6 ml/kg of fresh or salt water was instilled directly into the endotracheal tube. The animals were killed after 29 minutes, and the heart and lungs were then examined microscopically. The authors found that in the first 30 minutes, the brunt of the damage is borne by the vascular endothelium and not the alveolar cells.

The influence of gender and use of barium enema on morbidity in acute appendicitis

The records of 166 patients with appendicitis were analyzed by sex for time from presentation in the emergency department to surgery. Additionally, the effects of barium enema examinations on these times were noted. Our findings indicate that there was no significant delay in surgery based on gender (P = .42). However, those patients who had barium enema as part of their workup had significantly longer delays from presentation to surgery (P = .00005). These results support the notion that the most appropriate treatment for acute appendicitis is early diagnosis, a short preoperative resuscitation, and early surgical intervention. Barium enema is indicated only when the diagnosis is highly suspect and only if it can be carried out in a timely manner.