In 1994, the husband of the appellant, Linda Sosna, died following surgery to relieve a small-bowel obstruction. Sosna subsequently brought this medical-malpractice action against the surgeon, Dr. H. Bradley Binnington, in federal court based on diversity jurisdiction. A jury returned a verdict in favor of Binnington, and Sosna filed this appeal urging that she be granted a new trial because the District Court 1 committed several evidentiary errors related to the testimony of the defendant’s experts and the defendant himself. We affirm.
I.
On December 5, 1994, Richard Sosna underwent surgery to relieve an obstruction in his small bowel. His operation, which included an incidental appendectomy, was apparently unremarkable, as was his recovery, until the day after surgery. On December 6, he developed a fever and was started on antibiotics to combat any wound infection. On December 7, his surgical incision was noted to be red, infected, and oozing. In response, Binnington reopened the wound, drained it, and started the patient on a new course of antibiotics. By late in the day on December 7, Richard Sosna’s body was red and swollen from below his belly button to his thighs, including his genitals. On December 8, he was seen by an infectious disease consultant who made further changes in his course of *744 antibiotic treatment. On December 9, an MRI was performed that indicated the presence of air (and, consequently, a serious, possibly systemic, infection) within the small bowel and liver. He collapsed late that morning and Binnington returned him to the operating room early that afternoon; however, Binnington could detect nothing that was surgically correctable. Richard Sosna died in the early morning hours of December 10.
The parties agree that Richard Sosna was killed by an infection but disagree as to the infection’s etiology. Sosna presented a case based on two scenarios in which Binnington erred in his care of his patient. Sosna presented evidence that suggested that the cause of the wound infection and of the fatal sepsis (i.e., systemic, blood-born infection) was leakage of bacteria from the small bowel. This bacteria leaked either because Binnington faded to reheve the obstruction during the first surgery — which caused the bowel to become distended, lose cohesion, and allow the bacteria to “transmigrate” or “translocate” into the abdomen — or because Binnington failed to discover that Richard Sosna’s small bowel was already leaking bacteria during the first surgery. Thus, Sosna argued that Binnington either failed to relieve the small-bowel obstruction or failed to surgically resect (i.e., remove) the injured portion of bowel before December 9.
For his part, Binnington presented evidence that Richard Sosna’s wound infection was responding well to treatment and was unrelated to, and distinct from, his fatal sepsis. Additionally, Binnington’s evidence suggested that the physical evidence, particularly the autopsy report, was inconsistent with plaintiffs theory of the case. He also presented evidence that the precise cause of the fatal infection was unknown, that the fatal infection developed later than Sosna argued, and that the fatal infection likely spread from the small bowel to the liver (via the portal vein) and to the rest of the body via Sosna’s blood. Based on the evidence, Binnington argued, his surgical care of Richard Sosna was not substandard. The jury found in favor of Binnington.
II.
Sosna urges that the District Court committed four evidentiary errors that prejudiced her case and entitle her to a new trial. Specifically, the appellant contends that the District Court erred: when it limited the cross-examination of defendant’s expert, Dr. Jeffrey A. Drebin, regarding his personal surgical practices (which differed from Binnington’s); when it allowed defendant’s expert, Dr. John S. Daniels, to testify in areas beyond his expertise; when it allowed the defendant to testify that the plaintiffs translocation or transmigration theory was questionable and was “not held in high regard anymore by researchers in the field of surgical sepsis”; and when it allowed the whole of the pathologist’s report into evidence. We disagree and hold that, on the record before us, the District Court did not abuse its discretion when it made these evidentiary rulings.
The substantive law of Missouri governs this diversity case.
See Erie Railroad Co. v. Tompkins,
A. Dr. Drebin’s Testimony
Sosna first argues that the District Court erred when it limited the scope of her cross-examination of the defendant’s expert, Dr. Drebin. The District Court granted Binnington’s motion in limine and ruled that Drebin could not be questioned regarding his deposition testimony that he was critical of Binnington’s actions because he personally would have administered antibiotics peri-operatively (i.e., during surgery), would have decompressed the bowel, and would not have performed an incidental appendectomy. We think the District Court properly concluded that these were Drebin’s personal practices or opinions and therefore were not relevant to the standard of care and that, to the extent that they were relevant, they had a tendency to confuse the jury and to unfairly prejudice the defendant. See Fed. R.Evid. 403. Sosna’s theory of liability did not involve any of the practices that Drebin was critical of Binnington for performing (or for not performing). Had Sosna pursued a theory of liability premised on one of these actions, the associated evidence might have been admissible as relevant to the standard of care. However, because Sosna’s case was premised on a different theory and chain of events (i.e., the failure to relieve the obstruction or remove the compromised section of the small bowel), we see no abuse of discretion in the District Court’s ruling.
Even were we to find that the District Court erred when it limited the cross-examination, we would not reverse because Sosna was not prejudiced. In this case, the excluded evidence was not “of a critical nature”; hence, we have a “reasonable assurance that the jury would have reached the same conclusion had the evidence been admitted.”
Adams v. Fuqua Indus., Inc.,
B. Testimony of Dr. Daniels
Sosna also argues that the District Court erred when it allowed Binnington to present the testimony of Dr. Daniels, who
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is an internist and not a surgeon, regarding whether Binnington complied with the relevant standard of care. Rule 702 and the Supreme Court’s jurisprudence make it clear that a district court must not only act as a gatekeeper when ruling on the admissibility of expert testimony, but must also “continue to perform its gatekeeping role by ensuring that the actual testimony does not exceed the scope of the expert’s expertise.”
Wheeling Pitts. Steel v. Beelman River Terminals,
C. Dr. Binnington’s Testimony
Sosna next urges that the District Court improperly admitted hearsay testimony when it allowed Binnington to testify on re-direct that the plaintiffs transmigration or translocation “theory is not held in high regard anymore by researchers in the field of surgical sepsis.” Tr. Vol. V at 177. We disagree.
First, even if it were the case that Binnington had testified on direct examination that the transmigration “theory is not held in high regard anymore by researchers in the field of surgical sepsis,” Sosna would not be correct that inadmissible hearsay had been allowed into the record. Rule 703 permits an expert to “rely on otherwise inadmissible hearsay evidence in forming his opinion if the facts and data upon which he relies are of a type reasonably relied upon by experts in his field.”
Arkwright Mut. Ins. Co. v. Gwinner Oil, Inc.,
D. Autopsy Report
Finally, Sosna argues that the District Court admitted improper hearsay testimony when it allowed into evidence certain statements of the pathologist regarding Richard Sosna’s cause of death that were contained in the autopsy report. We disagree. The District Court did not abuse its discretion when it admitted the entire autopsy report into evidence under Rule 803(6) as a business record. It is of no avail for Sosna to argue that the statement that “[t]he ischemia of the segment of small bowel and acute tubular necrosis of the kidneys was most likely secondary to DIC and hypotension prior to death” was solely the opinion of the pathologist. Autopsy Rep. at 4. Rule 803(6) specifically speaks to, and makes admissible, records or reports
of acts, events, conditions, opinions, or diagnoses, made at or near the time by, or from information transmitted by, a person with knowledge, if kept in the course of a regularly conducted business activity, and if it was the regular practice of that business activity to make the memorandum, report, record or data compilation.
Fed.R.Evid. 803(6). We conclude that the opinions of the pathologist contained in his autopsy report fit comfortably within Rule 803(6)’s confines.
III.
For the reasons stated above, we affirm the judgment entered on the jury verdict in favor of Dr. Binnington.
Notes
. The Honorable Catherine D. Perry, United States District Judge for the Eastern District of Missouri.
