Combined preoperative irradiation and local hyperthermia delays early healing of experimental colonic anastomoses
J. Biert, W. Seifert, B. de Man, T. Wobbes, J. Hoogenhout and T. Hendriks
Department of Surgery, University Hospital Nijmegen, The Netherlands.
OBJECTIVE: To determine if a combination of preoperative irradiation and
local hyperthermia of a colonic segment is detrimental to subsequent early
anastomotic healing. DESIGN: A prospective randomized experimental trial.
SETTING: An animal research laboratory. INTERVENTIONS: Eighty male Wistar
rats were randomly divided into 4 groups. In each animal, a segment of the
colon was treated successively by (sham) irradiation and (sham)
hyperthermia. After 5 days, a colonic resection was performed and an
anastomosis was constructed; the distal limb consisted of (sham)
irradiated, (sham) hyperthermia-treated bowel. The rats were killed 3 or 7
days after surgery. MAIN OUTCOME MEASURES: Body weight, serum albumin and
protein levels, anastomotic bursting pressure, breaking strength, and
hydroxyproline content. RESULTS: All animals tolerated (sham) treatment
well. Weight was diminished, though not notably, in treated animals vs the
control group. After combined preoperative irradiation and hyperthermia,
the frequency of local anastomotic complications increased: 4 of 20 animals
had a covered perforation when they were killed. In this group, the
bursting pressure was lower 3 days after the operation (P = .008). The
breaking strength was also lower but not notably. The serum albumin level
was significantly lower in this group vs the control group (P = .006); the
serum protein level was not decreased. After 7 days, no differences existed
between the groups. The hydroxyproline content of the anastomotic tissue
was notably higher in rats treated with radiation plus hyperthermia vs
control rats (in both the 3- and 7-day groups). The anastomotic
hydroxyproline concentration did not differ between the groups.
CONCLUSIONS: The combination of preoperative irradiation and hyperthermia
results in increased local anastomotic complications. Anastomotic strength
is at risk in the first days after the anastomotic reconstruction.
Preoperative irradiation or hyperthermia alone does not lead to impaired
anastomotic healing in the early phase.
