Het volume van chirurgische ingrepen en de impact ervan op ... - KCE

72 Volume Outcome KCE reports 113
Because of lack of reliable short term mortality data, analyses on volume outcome
relationship are limited to 2-year mortality. This implies that additional outcome
measures such as postoperative bleeding rate and infection rate, which are listed in
Table 2.1 (page 16), are not analyzed in this report.
5.3.6 Volume outcome relationship
5.3.6.1 Analysis by hospital
MORTALITY RATE, BY HOSPITAL
Figure 5.12 presents the funnel plot of the number of pancreatectomies per centre and
the 2-year mortality (observed, i.e. without risk adjustment). The size of the point is
proportional to the number of hospitals with the same volume and the same outcome.
The horizontal line represents the overall 2-year mortality i.e. 53.2%. One low volume
centre is just above the 95% limits of variability, and one medium volume centre has
better performance. None of the hospitals are outliers above the 99.8% limits of
variability, but one medium volume hospital shows better outcome (low limits of 95%
variability).
Figure 5.12: Pancreatic cancer surgery: Funnel plot of 2-year mortality rate,
by hospital
DESCRIPTION OF DIFFERENCES IN CHARACTERISTICS ACCORDING TO
THE VOLUME CATEGORY OF THE HOSPITAL
Because the majority of centres were below the international cut off of 11
interventions/year, 3 volume categories were defined below this cut off and two above.
Table 5.26 shows that 2-year mortality is 65% in very low-volume hospitals (1-2
procedures/yr) and less than 50%. in hospitals with at least 6 procedures per annum.
Patients who are treated in hospitals with less than 6 interventions per year are 67
years old while patients treated in bigger hospitals are from 63 to 34 years old. The
percentage of patients with Charlson score ≥ 3 is 21% in very low-volume hospitals,
compared to 5.6% in the largest hospitals (>20/year). The highest volume hospitals
(>20/yr) have operated 25% of patients with malignant neoplasm of extrahepatic bile
ducts or ampulla of Vater (which have a better survival rate as seen in Table 5.25).