I don't think the risk of perforation while waiting for a CT is high, but why waste time, especially when the clinical diagnosis is unequivocal? In the study you quote, over 30% of the patients did not even get a CT- the clinical picture was compelling enough.
Waiting is waiting. Be it for a CT scan or until the next morning, the appendix doesn't care when it decides whether or not to perforate. I wasn't saying CT scans are necessary in all cases, I was making the point that the delay waiting for the CT scan in most institutions isn't as long as the wait that many patients who come in after hours have when their procedure is delayed until the morning, yet that is an acceptable practice, backed by the literature.
Per one
paper from a large university center, the delay is about 2.5 hours. In that same study, while delay in diagnosis did not correlate with higher rates of perforation, it
did lead to higher postop compications- and that was with only a mean delay of 3 hours.
Not entirely. The second article you cited is more convincing of this point, but the authors kind of misrepresented their findings if that is how you interpreted the first one. They are trying to make the case for an early surgical consult and the avoidance of imaging prior to the surgical team being called. They are also trying to make the case for diagnostic laparoscopy over CT scanning, as they found a diagnosis 91% of the time (compared to 84% with CT scan; don't worry about the 42% negative exploration rate). Here are some blurbs from the article.
article (reformatted) said:
1. The perforation rate was not a function of a delay in evaluation, as the duration from the onset of pain to ED evaluation in perforated appendicitis was (similar to nonperforated cases). The mean ED evaluation was (not statistically different between perforated and nonperforated cases).
2. Patients with postoperative complications had longer ED evaluations than did those without.
3. Patients with perforated acute appendicitis had a 19.8% morbidity and patients without perofration, 6.4%. The overall wound infection rate was 3.5% higher in perforated cases than in nonperforated cases (P=0.006). The incidence of intra-abdominal abscess was higher in perforated cases than in non-perforated cases (P=0.01)
Basically, what they are trying to say is that a delay in diagnosis in the ED leads to postop complications, even though their data shows that (a) there was no difference in the time of evaluation between perforated patients and nonperforated patients and (b) patients with perforated appendicitis had more complications. How can 2 and 3 be true? Perhaps because >50% of patients presented with atypical symptoms, and many were watched for a prolonged period of time. What wasn't clearly explained is how many patients in the observation arm had complications. It is possible that the patients who had an atypical presentation had a longer evaluation in the ED, were admitted/observed and they are the ones who had complications. We don't know, because it wasn't published, so we can't really make those conclusions.
I'd also like to point out that it took them 10.3 hours (+/- 14.1 hours) to get the patient to the OR based on a H&P alone (when surgery was consulted 4.7 +/- 5.2 hours after ED admission) vs. 19.5hrs +/-31.3 hours when a CT scan was ordered (and surgery was consulted 8.0 +/- 12.7 hours after ED admission).
1. I've never seen it take 3 hours to get a CT scan at our adult or children's hospital (maybe I'm living in my ivory tower again).
2. Why did it take them 12 hours to get the patient to the OR when a CT scan was ordered in comparison to 5 hours when one wasn't ordered? That sounds more like the fault of the surgical team over the CT scan, as those numbers don't add up.
Again, your point is well-taken, I just don't think the first study you used is one of the strongest articles on this subject and I don't think it helps support your case.
Sorry, SLUser. I won't practice any more EBM for the rest of this thread.
