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| ORIGINAL ARTICLE |
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| Year : 2017 | Volume
: 10
| Issue : 1 | Page : 97-102 |
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Postoperative outcome in major abdominal trauma: is the treatment of hypoalbuminemia beneficial?
Farahat Ibrahim, Essam F Abdelgalel
Department of Anesthesia and Surgical ICU, Zagazig University, Zagazig, Egypt
| Date of Web Publication | 3-Aug-2018 |
Correspondence Address:
Farahat Ibrahim
41 El Sahabah Street Hadayek Alkobbah, Cairo
Egypt
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/1687-7934.238472
Background It had been suggested that the use of fluids containing albumin in critically ill patients may increase the absolute risk for death when compared with crystalloids.
Objective The aim of this study was to compare the effect of albumin infusion versus conservative therapy on both serum albumin concentration (SAC) and patient outcome in case of postoperative hypoalbuminemia after exploration laparotomy for major abdominal trauma.
Patients and methods Sixty-four patients with major abdominal trauma who had undergone exploration laparotomy were studied. In addition to patient’s demographic data, serial postoperative SAC and intra-abdominal pressure up to the seventh day were measured. Moreover, clinical, laboratory, and radiological follow-up was conducted to evaluate the morbidity until patient discharge from the hospital. The mortality rate was also recorded.
Results There were no significant differences between patients who received albumin (group A) for the treatment of hypoalbuminemia and those who did not receive albumin (group B) as regards length of ICU stay (P=0.33), first postoperative day SAC (P=0.99), total complications (P=1), and individual postoperative complications [hemodynamic instability with vasopressor requirement (P=0.74), abdominal compartment syndrome (P=1), multiple organ dysfunction syndrome (P=1), and anastomotic leak (P=1), acute respiratory distress (P<0.6), and mortality (P=1)]. However, SAC was significantly higher on the third, fifth, and seventh day postoperatively in group A than in group B (P<0.001).
Conclusion Postoperative treatment of hypoalbuminemia in major abdominal trauma had no benefit as regards morbidity and mortality.
Keywords: albumin, major abdominal trauma, postoperative hypoalbuminaemia
How to cite this article:
Ibrahim F, Abdelgalel EF. Postoperative outcome in major abdominal trauma: is the treatment of hypoalbuminemia beneficial?. Ain-Shams J Anaesthesiol 2017;10:97-102 |
How to cite this URL:
Ibrahim F, Abdelgalel EF. Postoperative outcome in major abdominal trauma: is the treatment of hypoalbuminemia beneficial?. Ain-Shams J Anaesthesiol [serial online] 2017 [cited 2023 Dec 5];10:97-102. Available from: http://www.asja.eg.net/text.asp?2017/10/1/97/238472 |
| Introduction | |  |
Abdominal injury in the civilian population, either blunt or penetrating, is usually as a result of trauma due to road collisions, falls from height, gunshot or knife wounds, and rarely blast injuries. Hypoalbuminemia that is encountered after major abdominal surgery and in critical illness is a common problem. Multiple factors cause this problem and mainly include capillary leak with external distribution of albumin into the interstitial space and loss of albumin with blood in case of massive blood loss in trauma or during surgery [1]. Other possible factors include massive crystalloid infusion that may cause increased capillary permeability [2] and consequent organ dysfunction, especially pulmonary dysfunction [3].
Albumin is predominantly an extravascular protein, more albumin being outside the intravascular compartment than within it. This can be readily explained. At a serum concentration of 40 g/l, an average adult will have an intravascular mass of about 120 g of albumin. In the interstitium, the concentration is only 14 g/l, but with an interstitial volume of around 11–12 l there will be about 160 g of albumin in the extravascular space. Albumin is easily mobilized and the two ‘compartments’ are usually in a state of dynamic equilibrium. The use of albumin has become increasingly controversial, especially since the publication of the Cochrane Collaboration findings in the late 1990s. Instantly, albumin became known as a hazardous agent with obvious implications for medical practice. Each and every anesthetist, intensivist, and many other specialists were forced to re-evaluate their practice [4].
It is assumed that colloids such as albumin are immobile, yet albumin does move and is in a dynamic equilibrium between the intravascular and extravascular spaces [5]. Permeability changes are seen in illness. This loose term, usually used with considerable confidence, encompasses several postulated mechanisms, all of which result in fluid redistribution. Membrane transport probably plays a part as does lymphatic drainage. The effect is that, during some phases of illness, intravascular volume is difficult to sustain regardless of the fluid used, and the concept that large molecules sustain it better is only partially correct.
The correlation between colloid oncotic pressure and total protein is far more impressive than that between albumin and colloid oncotic pressure. A low serum albumin does not always indicate a low colloid oncotic pressure. As albumin moves out of the intravascular space with accompanying fluid, this will increase the amount of albumin in the extravascular space and influence the colloid oncotic pressure in that component. Lymphatic drainage usually returns it to the circulation but may be impaired in illness. The role of albumin in sustaining colloid oncotic pressure in these circumstances is unclear [6].
In this study, we prospectively studied the effect of albumin infusion in the correction of postoperative hypoalbuminemia versus conservative therapy on serum albumin concentrations (SACs) as well as the morbidity and mortality in patients with major abdominal trauma who have undergone exploration laparotomy.
| Patients and methods | | |
After approval of the medical and ethical committees and after obtaining informed consent from all patients, 64 patients of American Society of Anesthesiologists physical status I and II with major abdominal trauma and aged 18–45 years were prospectively studied in Zagazig University Hospital over a period of 18 months from March 2013 to September 2014. On the basis of a computer-generated randomization sequence, sealed, labeled envelops were prepared and patients were assigned to two equal groups of 32 patients each. Group A included patients who were routinely given albumin solutions in the first postoperative week if they were hypoalbuminemic (serum albumin <3 g/dl) (20% albumin solutions were given up to 200 ml daily or to the serum level ≥3 g/dl), and group B included patients who did not receive albumin if they were hypoalbuminemic. The study excluded patients with associated head trauma, major vascular injury, class IV shock, and patients with past history of endocrinal or organ dysfunction. Exploration laparotomy was performed for patients for whom intestinal resection anastomosis was performed for all with or without colostomy. Postoperatively, all patients were admitted in the ICU and monitored for central venous pressure, blood pressure (BP), heart rate, oximetry, and urine output. A resuscitation protocol was followed for the management of postoperative hypotension. Fluid infusion was given to keep central venous pressure in the range of 5–10 cmH2O. Inotropic support was given for patients with BP less than 90/60 and withdrawn gradually according to BP. Vasopressor infusion was given for patients who were unresponsive to both fluids and inotropes.
In addition to patient’s demographic data, preoperative baseline laboratory investigations were carried out. Postoperatively, serial SACs on the first, third, and fifth postoperative days, and 1 week after surgery were collected. In addition, volume of crystalloid and colloid replacement given during surgery, and total volume of postoperative albumin solution substituted in group A were recorded. All serum concentrations of albumin were quantitatively measured using the colorimetric method in the automatic Roche chemical analyzer (Roche, Rotkreuz, Switzerland). Postoperative follow-up included arterial blood gas analysis, electrolytes, complete blood count, hepatic and renal function tests, and coagulation profile every other day in the first week after surgery. Postoperative blood transfusion was carried out for patients to keep hemoglobin greater than or equal to 10 g/dl.
Moreover, the data collected included measurement of intra-abdominal pressure (IAP), which was measured using a urinary catheter every 8 h for 1 week after surgery. Intra-abdominal hypertension (IAH) was considered if the IAP was greater than 12 mmHg, and abdominal compartment syndrome (ACS) was considered if IAP was greater than 20 mmHg. ACS is defined as the presence of an IAP of at least 20 mmHg with or without an abdominal perfusion pressure less than 60 mmHg, recorded with a minimum of three standardized measurements conducted 1–6 h apart, and a new single or multiple organ system failure [7]. Other measurement recordings included hemodynamic instability with vasopressor need and postoperative complications, including organ insufficiencies, anastomotic leakage, dehiscence of laparotomy, and intestinal fistula. Length of ICU stay was also recorded.
Multiple organ dysfunction syndrome (MODS) was diagnosed as progressive and potentially reversible dysfunction of two or more organ systems based on laboratory and clinical data, which included renal insufficiency, hemodynamic instability or shock, respiratory insufficiency, and hepatic or cardiac failure [8].
Statistical analysis
On the basis of the previous study [9], the number of patients with postoperative complications was 29 (76.3%) in group A and 31 (81.6%) in group B. At 80% power and 95% confidence interval, the estimated sample will be 32 cases in each group [open Epi Info (EPI) (open source epidemiologic statistic for public health)]. Data were checked, entered, and analyzed using SPSS (version 20) (SPSS Inc., Chicago, IL, USA). Data were expressed as mean±SD for quantitative variables, and numbers and percentage for categorical variables. The χ2 test or Fisher’s exact results and test were used when appropriate. A P-value less than 0.05 was considered statistically significant and P-value less than 0.001 as highly significant.
| Results | | |
In this prospective study, the data recorded from 64 patients who were operated upon for exploration laparotomy after major abdominal trauma were studied. As shown in [Table 1], there was no significant difference between the two groups as regards age, duration of surgery, and the intraoperative fluid volume of both colloid and crystalloids. Moreover, there were no significant differences between the two groups as regards intraoperative blood transfusion and the length of ICU stay (P>0.05). | Table 1 Patient demographic data, duration of surgery, intraoperative fluids, volume of albumin, and length of intensive care unit stay
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In [Table 2], there were no significant differences in preoperative and the first day postoperative SAC between the two groups. It was noticed that the SAC was significantly decreased postoperatively in both groups. However, there were statistically significant differences between the two groups in SAC on the third and fifth day and 1 week after surgery (P<0.001). | Table 2 Preoperative and postoperative serum albumin concentration (g/dl)
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The measurements of the IAP are shown in [Table 3]. There was no significant difference between the two groups on the first, third, and sixth postoperative day (P>0.05). Moreover, there was no statistically significant difference between the two groups in the occurrence of ACS. There were three cases of ACS in group A and four cases in group B (P>0.05).
As regards postoperative complication ([Table 4]), there were no significant differences between the two groups in individual complications, including ACS (P=1), hemodynamic instability with vasopressor requirement (P=0.74), acute respiratory distress syndrome (ARDS) (P=0.6), MODS (P=1), anastomotic leak (P=1), and mortality (P=1).
In group A, there were 21 cases of postoperative complications: three cases of ACS, three cases of hemodynamic instability, three cases of ARDS, four cases of multisystem organ failure (MODS), five cases of anastomotic leak, and three patients died (one died due to ACS and two due to MODS and sepsis).
In group B, there were 20 cases of postoperative complications: four cases of ACS, four cases of hemodynamic instability, one case of noncardiogenic pulmonary edema, three cases of MODS, six cases of anastomotic leak, and two patients died due to sepsis and MODS.
| Discussion | | |
Surgery in the abdominal cavity is followed by a larger decrease in SACs, as in other surgical procedures [10]. Enhanced capillary permeability causes escape of fluid and albumins from the vessels, and returns to normal in 12–24 h after surgery; however, after extensive surgery, albumin was found in the extravascular compartment 7–10 days after surgery [5]. This finding may explain the significant hypoalbuminemia (vs. preoperative values) noted on the first days after surgery in our group that did not receive albumin replacement, and the slow albumin level increase in both groups in the week after surgery. Two previous studies reached similar conclusions [9],[11]. Therefore, SAC reflects mainly the patient’s general condition due to the extent of systemic inflammatory response and capillary permeability [12]. It increases with successful recovery. The increase in SAC in the recovery phase is more or less the same in patients who received albumin replacement therapy as in those who did not.
In the current study, the postoperative albumin concentration values in both groups were significantly lower compared with the preoperative values, and albumin infusion did not prevent a decrease in postoperative albumin concentration in the supplemented group. This may be attributed to the fact that all patients with abdominal injuries who had undergone multiple intestinal resection anastomoses had systemic inflammatory response syndrome with sepsis syndrome due to contamination of the peritoneal cavity by the intestinal contents, with a spread of organisms into the circulation through injured mesenteric vasculature. It was known that sepsis syndrome increase capillary permeability with induced capillary leak of fluids containing albumin. Moreover, the artificial human albumin does not sustain in the circulation for long time as the natural albumin; the intravascular half-life of artificial albumin is 16 h. These data are in accordance with the other studies of albumin concentrations in surgical and critically ill patients [7],[9]. However, in patients after abdominal aortic surgery, albumin concentration did not decrease significantly when treated for 4 days with high volumes of albumin solutions, but in their group that did not receive albumin supplementation, SACs decreased [13]. Aman et al. [14] in their study in critically ill patients have concluded that there was a correlation of decreased level of plasma proteins (albumin and transferrin) with acute lung injury or ARDS. This was attributed to increased permeability with extravascular escape of plasma albumin and transferrin in critically ill patients [14].
Moreover, in the current study, the postoperative albumin replacement in group A patients had no effect on ameliorating the incidence of morbidity and mortality compared with group B patients who did not receive albumin. These results are similar to that demonstrated in surgical ICU patients [15] and critically ill ICU patients [16]. No benefits were seen in cases after liver transplantation surgery [17] and in cases of advanced abdominal malignancy [9],[18]. Moreover, in multicenter randomized controlled trials, no benefit in outcome and mortality was seen in patients with sepsis who were treated with albumin and those who were given crystalloids [19],[20].
Albumin can support colloid oncotic pressure, but a few small studies have not been able to demonstrate that this influences outcome [21]. In a very small study, its use as a nutritional supplement appeared beneficial, whereas in the critically ill it was of no obvious benefit [22]. In larger studies in the critically ill, no benefit from the routine use of albumin was seen [15]. In ICU patients, it did not improve fluid balance and pulmonary edema [23], nor did it reduce mortality, duration of ICU stay, mechanical ventilation, or renal replacement therapy [24]. In elderly patients after cardiac surgery, there was no difference in renal dysfunction between the group with albumin supplementation and the group given 6% hydroxyethyl starch instead of albumin; moreover, endothelial activation was even lower in the hydroxyethyl starch group [25]. Further, postoperative blood loss in cardiac surgery was more in cases given albumin compared with those given crystalloids [26].
Beyond its oncotic pressure-related effects on the intravascular volume, albumin in low concentrations has marked anti-inflammatory and oxidative properties [27], which were nicely demonstrated both in experimental animals [28] and in patients with acute lung injury [29]. Nevertheless, the overall result of Saline versus Albumin Fluid Evaluation (SAFE) study in ICU was that albumin did not show any outcome benefit as a resuscitation fluid when compared with saline [16]. Moreover, patients with traumatic brain injury treated with albumin had increased mortality compared with saline-treated patients [30]. This was attributed to the probability of albumin-induced increases in the intracranial pressure [31].In their elegant rodent study, which represents the logic extension of a previous work [32], Kremer et al. [33] observed that the administration of human serum albumin (HSA) 4% normalized the endothelial flow dilation in vitro. In contrast to these therapeutically promising properties, HSA 20% exerted just the opposite effects; not only did it fail to attenuate the endotoxin-induced hyperinflammation, but, in particular, HSA 20% significantly reduced the expression of heme oxygenase-1. However, in their study, Delaney et al. [34] demonstrated that the use of albumin-containing solution in the resuscitation of patients with sepsis may decrease mortality compared with resuscitation with other fluids.
ACS can result from trauma, major surgery, and numerous other conditions requiring large-volume resuscitation. The critical IAP in the majority of patients lies in the range of 10–15 mmHg [35]. A multicenter study from 13 ICUs across six countries established that 41.2% of critical care patients had a normal IAP less than 12 mmHg, 58.8% had IAH above 12 mmHg, 28.9% had IAP above 15 mmHg, and 8.2% presented with IAP greater than 20 mmHg [36]. The relative frequency of IAH and ACS, which is associated with mortality rates ranging from 25 to 100%, argues for increased vigilance and more frequent monitoring in patients at risk of developing high IAP. The keys to prevention and successful management of IAH and ACS are maintaining a high index of suspicion, obtaining serial IAP measurements, and intervening early.
In the current study, the follow-up of IAP that was measured every 8 h daily for the first postoperative week showed that 9.4 and 12.5 % of patients in groups A and B, respectively, had ACS and 40.6 versus 34.4% had IAP 12–20 mmHg and the remaining 43.8 versus 50% had IAP less than 12 mmHg. This may be attributed to edema in the intestine and mesentery due to extensive fluid infusion, intestinal manipulation during surgery, and soiling of the abdominal cavity by the intestinal contents. However, cases of ACS were associated with organ dysfunction and anastomotic leak that were explored again.
| Conclusion | | |
From these results and the previous studies, we concluded that albumin replacement in postoperative hypoalbuminemia is of no significant value in decreasing the morbidity and mortality in the critically ill surgical cases. More studies are needed to evaluate the type of patients, the timing, dose, and concentration of albumin replacement to give optimum results.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2], [Table 3], [Table 4]
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