To the Editor:
We read with great interest the article by Dr. Birgitte Brandstrup and colleagues1 in the November 2003 issue of the Annals of Surgery. Their objective was to investigate the effects of restricted versus standard intravenous fluid regimens on complications after colorectal surgery. Having carefully studied the paper we have several comments regarding the design and conclusions of the study.
Although this was a multicenter study they do not mention any protocol or guidelines for fluid management applied during the postoperative period in the standard regimen group. Furthermore, they state that postoperative fluid administration was given according to the “standard” treatment of each hospital and each ward. We find this a significant flaw in the design of the study as major differences in fluid resuscitation can occur between physicians or centers. When assessing the complication rate following an intervention, it would be expected to find some criteria for the prophylaxis measures and the treatment of these complications. In the present study, each 1 of the 8 hospitals used its own routine for antibiotic and antithrombosis prophylaxis.
In addition, the researchers intended to include patients with ASA score group I-III. However, due to their exclusion criteria, 98% of patients included had an ASA score of I-II. Hence, most of their patients were relatively healthy. Our clinical experience taught us that the major problems with fluid resuscitation occur in patients with ASA III-IV.
Regarding the regimens: maintenance fluid support in the restricted group during the surgical procedure and the postoperative period consisted of 5% glucose. The recent trauma and critical care literature are not in favor of this kind of therapy.2 In addition, the standard group was treated with normal saline and HAES 6%, however, when the recommended dose of HAES was reached albumin 5% was administered. The use of 5% albumin for fluid resuscitation is controversial, especially as it may aggravate edema formation in areas of leaky capillaries.3,4 Hence, we have to conclude that the regimen and types of fluid used are not the currently practiced nor advised.
The total amount of fluid administered in the operative day ranged between 1100 to 8050 mL in the restricted group and between 2700 to 11,083 mL in the standard group. We noted the large range of fluids administered to different patients in each group. Based on our experience, normally ASA I-II patients undergoing elective colectomies do not require such large amount of fluids.
Although the randomization was computer generated, in the restricted group most of the patients had an ileocolic anastomosis contrary to a minority in the standard group. We find it of importance to note that ileocolic anastomoses are considered less prone to complications. Interestingly, this fact by itself may have caused a bias in the results in favor of the restricted group. Seven percent of patients in the standard group required repeated surgical interventions due to bleeding and the mortality rate of this group was 4.7%. We find these figures alarming in the setting of elective colorectal surgery, moreover in ASA I-II patients. The authors do not state whether each complication occurred in a different patient or could it be that the same patient that had an anastomotic leakage also suffered from sepsis and intestinal obstruction. Although this is quite possible, it would affect the calculated results for the number of complications per patients.
To conclude, the work presented here demonstrated some flaws, which will limit the interpretation and application of these results. Hence, a properly designed study is necessary to identify an adequate fluid resuscitation protocol in postoperative surgical patients.
Yoav Mintz, MD
Yoram G. Weiss, MD
Avraham I. Rivkind, MD, FACS
Hadassah University Hospital
Jerusalem, Israel
Mintzy@md2.huji.ac.il
REFERENCES
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