Acute Postoperative Phase Research Articles

Time-scale of interleukin-6, myeloid related proteins (MRP), C reactive protein (CRP), and endotoxin plasma levels during the postoperative acute phase reaction.

During goitre surgery (25 patients) and after major abdominal surgery (52 patients), we studied the plasma levels of endotoxin, interleukin-6 (IL-6), C reactive protein (CRP), and the so called myeloid-related proteins (MRP), MRP8, MRP14, and the heterocomplex of both single proteins, MRP8/MRP14 in three intervals: pre-, intra-, and postoperative. We observed that CRP levels began to increase on the first postoperative day, reaching a maximum on day 2 (median levels of 185 mg/L after major surgery and 77 mg/L after goitre surgery). IL-6 levels peaked at the end of the operation, remaining elevated for 6 h following abdominal surgery (299 pg/mL) and peaked on day 1 after goitre surgery (63 pg/mL). An increase in MRP8/MRP14 levels began toward the end of abdominal surgery, and maximum levels were recorded until 5 days after the operation (5,695 micrograms/L). Plasma levels were significantly elevated 2 and 6 h after minor surgery (3,619 micrograms/L), while no changes were observed in the plasma levels of MRP8 and MRP14. Evidence of significant endotoxemia was found after the induction of anesthesia in the abdominal surgery group (.13 endotoxin units (EU)/mL) and after skin incision (.07 EU/mL) in the thyroid surgery group. The observed time sequence, starting with the release of bacterial products at an early stage, followed by the secondary stimulation of factors inherent to the acute phase led us to conclude that certain bacterial compounds, probably deriving from the gastrointestinal tract, trigger the postoperative acute phase reaction and are responsible for the activation of monocytes/macrophages and granulocytes.

Endotoxin-induced cytokine release from whole blood - similarities between monocyte dysfunction in septic disease and during postoperative acute phase response

Plasma levels of endotoxin, TNFα, interleukin-1β (IL-1β), and interleukin-6 (IL-6) as well as the endotoxin-induced release of these cytokines from whole blood were determined in 20 patients after elective aseptic surgery and eight patients suffering from septic disease. Blood samples were drawn before surgery as well as once daily over 7 days postoperatively. Endotoxin plasma levels increased on the day of the operation from 0.025 ± 0.005 EU/ml to 0.099 ± 0.022 EU/ml and remained elevated for 1 day. No changes were noted in the plasma levels of TNFα and IL-1. Levels of IL-6 increased to 198 ± 52 pg/ml on the day of the operation, while the release of TNFα and IL-6 markedly declined after whole blood was stimulated with endotoxin. The difference between basal and stimulated TNF values amounted to 505 ± 129 pg/ml preoperatively and 132 ± 41 pg/ml after the operation and 297 ± 28 pg/ml and 137 ± 43 pg/ml for IL-6. From the second day of the postoperative period onwards, the endotoxin-induced release of IL-6 was higher than the preoperative values. The results of whole blood stimulation in patients with sepsis were similar to those achieved directly after elective surgery. The cytokine release of TNFα, IL-1β, and IL-6 was reduced. We conclude that, during the early aseptic acute phase reaction, the changes in the functioning of monocytes resemble - qualitatively - those occurring during septic disease, and that this may be related to endotoxemia originating in the gastrointestinal tract.

Intestinal motility after massive small bowel resection in conscious canines: comparison of acute and chronic phases.

To evaluate intestinal function after 80% massive distal small bowel resection (MSBR), we continuously monitored interdigestive and postprandial bowel motility using bipolar electrodes and/or contractile strain gauge force transducers in conscious beagle dogs before and at 2-4 weeks (acute postoperative phase; acute phase) and 8-13 months (chronic postoperative phase; chronic phase) after the surgery. Fasting duodenal migrating myoelectric (or motor) complexes (MMC) occurred at longer intervals in the acute phase after 80% MSBR than in control beagles. Intervals between duodenal MMC in the chronic phase were similar to those found in control beagles. MMC arising from the duodenum were often interrupted before the jejunum above the anastomosis in the acute phase, and a slight recovery of propagation frequency to the jejunum above the anastomosis was observed in the chronic phase. However, duodenal MMC did not migrate smoothly to the terminal ileum in both groups. In the acute phase, the velocity of duodenal MMC propagation was slowed in every intestinal segment, including the duodenum and the jejunum above the anastomosis, and had not recovered even long after the operation. The duration of the postprandial period without duodenal MMC was prolonged significantly in the acute phase postoperatively. Although it shortened in the chronic phase, it still remained significantly longer than in controls. These findings suggest that changes in gut motility after MSBR tend to compensate for the shorter intestine and maintain small bowel absorption early postoperatively. However, these compensatory changes decrease over the long term, and their adaptive contributions to increased intestinal absorption may decrease as well.

La corticothérapie et l'hémodilution diminuent-elles l'inflammation postopératoire après chirurgie maxillofaciale ?

To assess the efficiency of corticosteroids and preoperative acute normovolaemic haemodilution (PANHD) in reducing postoperative inflammation after maxillofacial surgery. Randomized clinical trial. Thirty-two patients scheduled to undergo maxillary osteotomy for facial dysmorphia were randomized into four groups of eight (PANHD or not; corticosteroids or not). PANHD decreased haematocrit to 30%. In the corticosteroid groups, methylprednisolone 1.5 mg.kg-1 was given intravenously at the beginning of surgery (after PANHD in haemodiluted group), and after surgery, 1.5 mg.kg-1 iv daily for three days. Postoperative inflammation was assessed with an X-Ray technique (radiotelemetry) providing data on tissue thickness (extent of facial oedema), and by measurement of plasma concentrations of four acute phase proteins during the first postoperative week. No change in facial oedema and in acute phase proteins occurred with PANHD. Corticosteroids decreased postoperative oedema and acute phase proteins. Corticosteroids decrease postoperative inflammation after maxillofacial surgery but not PANHD.

New aspects concerning the regulation of the postoperative acute phase reaction during cardiac surgery

During a cardio-pulmonary bypass, as well as post-operatively, high levels of endotoxin, interleukin-6 (Il-6) and C-reactive protein (CRP) were measured in 30 patients. A significant increase in endotoxin plasma level occurred during surgery, culminating in a peak during reperfusion. Plasma levels of endotoxin continued to be slightly raised until the fifth day after surgery, whereas those of Il-6 rose at the time the operation came to an end and were at their highest 6 h later. CRP levels were also high, post-operatively, and were markedly raised on day 2. A definite, statistically significant correlation between the plasma levels of endotoxin and Il-6 during the operation was established, leading us to conclude that the endotoxin liberated during cardiac surgery acts as the main trigger in the release of 11-6 and thus induces the post-operative acute phase reaction. There was no evidence of a correlation between CRP and endotoxin or Il-6 plasma levels.

Incidence and pathophysiological relevance of postoperative endotoxemia

Patients who underwent surgical procedures usually develop elevated body temperature, changes of plasma levels of some proteins, and leucocytosis. These alterations are summarized as the postoperative acute-phase reaction. Also endotoxin can induce the described phenomena suggesting that endotoxin may play a role concerning the induction of the acute phase reaction. In order to test that hypothesis we determined endotoxin plasma levels preoperatively and daily postoperatively in patients who were operated on because of goiter ( n = 20), colonic, pancreatic and gastric diseases ( n = 58). A significant increase of endotoxin plasma levels was found at the first and third day after abdominal surgery whereas after goiter surgery the increase revealed to be only very slight. However, the decrease between the first and second postoperative day in the latter group was again statistically significant suggesting postoperative endotoxemia even after minor operations. Furthermore a correlation between the amount of circulating endotoxin and pulmonary or infectious complications could be established in patients after major operations even at the first postoperative day suggesting a pathogenetic relevance of postoperative endotoxemia.

CT-stereotactic fibrinolysis of spontaneous intracerebral hematomas.

CT-stereotactic fibrinolysis is an effective alternative to surgical and conservative therapies for intracerebral hematoma. The method consists of stereotactically puncturing and partially evacuating the hematoma. After fibrinolysis using urokinase, the residual hematoma is completely evacuated through a catheter inserted in the cavity of the hematoma. The operation is usually performed under local anesthesia. Stereotactic methods are safer and less invasive than other methods. Since October 1985, a total of 85 patients have been treated with this method in the Department of Stereotaxy and Neuronuclear Medicine at the University of Freiburg Medical School. Although 25 patients died (29.4%) during the mean follow-up period of 20 months, only 16 (18.8%) died in the acute postoperative phase or within the first 60 days after evacuation. Eighteen patients (21.2%) had died six months after the operation. The quality of life of the 60 surviving patients, as measured on the Karnofsky Scale at follow-up, was very good to good in 70% and moderate in 23.3%. Only 6.7% of the patients were so disabled that they required special care and assistance or had to be placed in a nursing home. The long-term results are thus very encouraging.

Effects of Sodium Pentobarbital Anesthesia on Blood Flow in Skin, Myocutaneous, and Fasciocutaneous Flaps in Swine

Drug effect on flap blood flow is most commonly determined in anesthetized animals, yet the effect of the anesthetic is often poorly understood. Halothane and nitrous oxide cause profound changes in skin blood flow and thus provide an unsuitable anesthetic technique for use in measuring drug effects on skin and myocutaneous flaps in swine. The goal of this study was to determine the effects of sodium pentobarbital anesthesia on cardiovascular parameters and blood flow in skin, myocutaneous, and fasciocutaneous flaps in pigs. In seven pigs, 7 forelimb skin flaps, 7 forelimb fasciocutaneous flaps, 14 arterial buttock flaps, and 14 latissimus dorsi flaps were created. Blood flow was measured at 2-cm intervals along each flap while the animal was awake and anesthetized. A cardiac depressant effect of pentobarbital was observed, but no change in blood flow could be demonstrated in control skin or control muscle. However, pentobarbital did significantly increase blood flow in all viable portions of arterial and random skin flaps, fasciocutaneous flaps, and the cutaneous segments of the latissimus dorsi flap. These demonstrated effects of pentobarbital should be taken into consideration in designing and analyzing studies of flap blood flow in the acute postoperative phase.

Quantitation of "acute-phase proteins" postoperatively. Value in detection and monitoring of complications.

Serial determinations of serum C-reactive protein are helpful in the detection and monitoring of postoperative complications associated with inflammation and/or tissue necrosis. The serum C-reactive protein level begins to increase within sex hours after operation, peaks on the second day, and by the third postoperative day begins to decrease toward the preoperative level. In cases with surgical complications involving inflammation, serum C-reactive protein levels remain elevated and do not show a decline on the third postoperative day. Serum levels of other "acute-phase proteins," such as alpha-1 acid glycoprotein, ceruloplasmin, alpha-1 antitrypsin, and haptoglobin, were found to increase in response to surgical procedures, but subsequent to the increase in C-reactive protein. These other proteins offer no additional information in monitoring the postoperative acutephase response,