Direct Identification of Anastomotic leakage with Microdialysis in Abdominal surgery

Failure of anastomotic healing is a major complication after esophagectomy,
pancreaticoduodenectomy and colorectal surgery. It has been shown to occur in
respectively 1,4 * 20%, 5-15% and 2-13% (Yeh et al., Harling et al.).. The
prognosis of these patients is uncertain and the outcome after such a
complication is dependent on early diagnosis and timely surgical or
radiological intervention. So far, identification of impaired anastomotic
healing exists of clinical examination, lab-results and CT-scanning. However,
in the early postoperative fase, these investigations lack sensitivity. Despite
the reported incidence of AL and its extensive consequences on morbidity,
mortality, hospital stay and costs, only a few studies have been undertaken to
evaluate diagnostic tools for early detection. It has been shown that a
decrease in local blood flow is a strong indicator for anastomotic leakage
after Upper and lowerGI surgery. Decreased blood flow causes local ischemia
which can be measured by microdialysis. Microdialysis is a relatively new tool
for continuous measurement of levels of pyruvate, lactate, glycerol and
glucose. The lactate / pyruvate ratio is a strong indicator for hypoxia,
whereas decreased glucoselevels indicate increase in metabolism. When local
ischemia progresses cells are broken down and glycerol is released. (Jansson et
al. Scand J Gastroenterol. 2004 May;39(5):434-9). By measurement of these
substances next to the anastomosis after upper- or lowerGI surgery anastomotic
leakage may be identified in a early preclinical stage.

Determinqtion of postoperative microdialysis values for pyruvate, lactate,
glycerol and glucose after esophagectomy and gastric pull-upk,
pancreaticoduodenectomy and sigmoid or rectum resection.
Early detection of anastomotic laekage in patients after sigmoid or rectum
resection.

investigational cohort study

For patients in the DELFT-study, at the final stage of the esophagectomy a 0,9
mm microdialysiscatheter is placed subcutaneously next to the cervical
anastomosis. Next to this a referencecatheter is placed in the abdominal
subcutis located at least 10 cm from the laparotomy.
In the PALM-study, after the pancreaticoduodenectomy the microdialysis catheter
is placed next to the pancreaticoenterostomy. A second catheter is placed in
the subcutaneous fat in the abdominal wall 10 cm from the subcostal incision.
During the colorectal resection in the MICRo-study, the tip of the
microdialysis catheter is placed next to the anastomosis. A reference catheter
is placed in the adbominal wall.
Every 4 hours a sample is taken from both the anastomotic catheter as wel as
the subcutaneous catheter.
Every 12 hours a brief physical examination is carried out, as this is routine
in the daily care of postoperative patients, this does not convey additional
burden for the patient.
Virtually no catheter related complications were described in previous studies
(Reid et al. Ann Plast Surg. 2003 Dec;51(6):575-8). Patients should experience
no more discomfort from a microdialysis catheter than from routinely used
draining systems. Complications from devices like these include superficial
infection and pain. In case of both these complications, the microdialysis
catheter will be removed.