Is contrast as bad as we think? Renal function after angiographic embolization of injured patients

BACKGROUND: Angiographic embolization (AE) is increasingly used to control bleeding after severe trauma. Serious concerns have been raised about the safety of high-volume i.v. contrast in hypotensive, hypovolemic patients. STUDY DESIGN: In a prospective cohort study, 100 consecutive trauma patients underwent AE for bleeding in the abdomen and pelvis. Serum creatinine (Cr) levels were measured before the procedure and up to 5 days after the procedure. Contrast nephropathy was defined as an increase in Cr levels after AE of more than 25% over the baseline measurement. An average of 248 +/- 59 mL of nonionic, low-osmolality contrast was used in all cases. RESULTS: Compared with the baseline, no increase in Cr levels after AE was observed among all patients (1.02 +/- 0.24 versus 0.94 +/- 0.26 mg/dL; p = 0.01) or among subgroups of patients who had any of the following risk factors for renal failure: older than 60 years, Injury Severity Score > or = 15, shock on arrival, renal injury, elevated Cr levels (> or = 1.5 mg/dL) before AE, or administration of a high volume of contrast (> 250 mL). Contrast nephropathy developed in five patients by means of mild Cr elevations. In all of these patients, Cr returned to baseline within 5 days of AE. Renal failure requiring hemodialysis developed at 41 and 55 days after AE in two patients with multiple organ failure who eventually died. CONCLUSIONS: Administration of nonionic contrast during AE causes mild and transient contrast nephropathy in 5% of severely injured patients. Our study adds additional support for the safety of AE for trauma.     

Relationship between release of beta-endorphin, cortisol, and trauma severity in children with blunt torso and extremity trauma

PURPOSE: To determine the levels of beta-endorphin and cortisol in children with multiple injuries and to determine whether there is any difference between and compare the severity of trauma and beta-endorphin and cortisol release as calculated using Pediatric Trauma Score (PTS). METHODS: During a 10-month period, 80 children with multiple injuries admitted to a University Hospital's Pediatric Surgery Department were studied. Blood samples were obtained immediately at admission and a PTS of each patient was calculated. The correlation between PTS and hormonal values were searched. The children were classified into two groups according to their PTS. Group 1 had PTS >8 and group 2 had PTS < or =8. The two groups were also compared with respect to their beta-endorphin and cortisol values. RESULTS: There was a linear correlation between beta-endorphin and cortisol values and the injury severity. The levels were higher in the patients with more severe injuries. There were 60 patients in group 1 and 20 patients in group 2. Their ages were 9.2 +/- 4.1 and 9.7 +/- 4.2 years, respectively (p > 0.05). The mean PTS for group 1 patients was 11 +/- 0.8 and for group 2 patients was 7.4 +/- 1.2 (p < 0.001). The mean plasma beta-endorphin concentrations were 124.4 +/- 114.4 pg/mL in group 1 patients and 261.6 +/- 231.2 pg/mL in group 2 (p < 0.001). The respective plasma cortisol concentrations in the two groups were 22.5 +/- 10.3 microg/dL and 30.8 +/- 17.2 microg/dL (p < 0.05), respectively. CONCLUSIONS: The results of this study show that the plasma beta-endorphin and cortisol levels are elevated in children after blunt trauma and the degree of elevation is related to the injury severity.     

Relationship of proximal fixation to renal dysfunction in patients undergoing endovascular aneurysm repair

Technological advancements have lead to dramatic improvements in stentgraft device design resulting in more trackable delivery systems and transrenal uncovered stents and barbs for better fixation. Transrenal bare-stents may limit stentgraft migration, particularly in patients with short or flared proximal aortic necks. However, potential disadvantages might be in worsening renal function, particularly in patients with preexisting renal insufficiency. We retrospectively analyzed our recent 7 year experience of patients undergoing endovascular aneurysm repair (EVAR) using a variety of stentgrafts with and without transrenal bare-stent fixation. Patients were divided into 2 groups; infrarenal fixation (IRF) vs transrenal fixation (TRF), or patients with preoperative serum Cr values that were normal (= or <1.5 mg/dl) vs slightly elevated (1.6-2 mg/dl), vs markedly elevated (2.1- 3.5 mg/dl). The exclusion criteria included patients with chronic renal insufficiency (CRI) on hemodialysis, and preoperative high-grade renal artery stenoses requiring angioplasty and stenting. Of 705 patients that underwent EVAR, 496 (IRF: 385 [78%], and TRF: 111 [22%]) were available with routine evaluations of serum Cr and CT scans. Preexisting comorbidities, mean procedure contrast volume, and postprocedure follow-up were similar in both groups. In the immediate postoperative period, mean serum Cr did not change significantly in either the IRF group (1.3+/-0.7 mg/dl to 1.2+/-0.9 mg/dl) or the TRF group (1.3+/-0.5 mg/dl to 1.3+/-0.6 mg/dl). Mean serum Cr did, however, significantly increase over longer follow-up in both groups: 1.4+/-0.8 mg/dl for IRF (P<0.03), and 1.5 +/- 0.8 mg/dl for TRF (P<0.01). Cr clearance was similarly unchanged in the immediate postoperative period (58+/-23 to 61+/-25 ml/min/1.73 m2 for IRF group, 53+/-17 to 55+/-17 ml/min/1.73 m2 for TRF group), but was significantly decreased in longer follow-up (53+/-23 ml/min/1.73 m2 for IRF, p<0.02: and 48+/-16 ml/min/1.73 m2 for TRF, P<0.01). There were no significant differences in serum Cr increase (p=0.19) or Cr clearance decrease (p=0.68) between the IRF and TRF groups. Small renal infarcts were noted in 6 patients (1.6%) in the IRF group, and in 8 patients (7%) in the TRF group (p=0.37). Of patients with normal preoperative renal function, renal dysfunction developed in 7.7% of IRF group and 6.1% of TRF group (p=0.76). In patients with preexisting CRI, renal dysfunction developed in 18.2% of IRF group, and 17.1% of TRF group (p=0.95). Eight patients with postoperative renal dysfunction, 5 (1.3%) from IRF group and 3 (2.7%) from TRF group subsequently required hemodialysis, and this difference was not statistically significant (p=0.91). We also analyzed 200 consecutive patients undergoing EVAR with intra-arterial contrast agents with and without preexisting CRI not on dialysis. The groups were identified on the basis of preprocedure serum Cr: group 1 (n=108), Cr less than 1.5 mg/dL (normal range); group 2 (n=65), Cr 1.5 to 2.0 mg/dL; group 3 (n=27), Cr 2.1 to 3.5 mg/dL. Routine precautions in patients with CRI included preoperative intravenous hydration with 2 L of normal saline solution, discontinuation of all nephrotoxic drugs, intraoperative administration of mannitol (0.5 g/kg intravenously), and use of nonionic, low osmolar intra-arterial contrast agent (Omnipaque 350). One-hundred and eight patients had normal renal function (group 1), and 92 patients had preexisting CRI with baseline Cr 1.5 to 2.0 mg/dL (group 2, n=65) or 2.1 to 3.5 mg/dL (group 3, n=27). Comorbid conditions included coronary artery disease (group 1, 51%; group 2, 49%; group 3, 59%), hypertension (group 1, 39%; group 2, 46%; group 3, 52%), and diabetes mellitus (group 1, 25%; group 2, 35%; group 3, 48%). In groups 1, 2, and 3, the mean volume of low osmolar contrast agent used was 210 cc, 160 cc, 130 cc, respectively; hemodynamic instability developed in 3, 1, and 1 patient, respectively. The incidence of postoperative complications between the 3 study groups was not statistically different. In grications between the 3 study groups was not statistically different. In group 1 a transient increase in serum Cr (>30% over baseline and >1.4 mg/dL) was noted in 3 patients (2.7%), 2 of whom (1.9%) required temporary hemodialysis and 1 (0.9%) who died of renal failure. In group 2 a transient increase in serum Cr was noted in 2 patients (3.1%); both patients (3.1%) required temporary hemodialysis, and 1 patient (1.5%) died of renal failure. In group 3 a transient increase in serum Cr was noted in 2 patients (7.4%); 1 patient (3.7%) required temporary hemodialysis, and 1 patient (3.7%) died of renal failure. Perioperative hypotension significantly increased the risk for elevated serum Cr and death (p<0.05), and larger contrast volume was associated with an increase in serum Cr (p<0.05) during the postoperative period. Following EVAR renal function declines slightly with both IRF and TRF. Our data show no overall difference between patients with IRF and TRF with respect to infarcts, decline in renal function, or onset of dialysis. There were a slightly greater number of renal infarcts in the TRF group, but these infarcts were clinically inconsequential. In patients with CRI, EVAR with intra-arterial radiographic contrast agents is believed to impair renal function, and CRI is considered a relative contraindication to the procedure. Results of our investigation indicate that risk for worsening renal insufficiency, dialysis, and death is only slightly and not significantly greater in patients with CRI compared with patients with normal renal function. With appropriate precautions of avoiding perioperative hypotension and limiting the volume of nonionic contrast agents, CRI need not be a contraindication for EVAR with intra-arterial contrast agents.     

Blood transfusion in critically injured patients: a prospective study

BACKGROUND: Despite evolving evidence that transfusion risks outweigh benefits in some patients, the critically injured continue to receive large quantities of blood. The present study evaluated patterns of red blood cell transfusions and risk factors for transfusions at various stages of admission in trauma patients. STUDY DESIGN: Prospective, observational study of transfusion practices in patients (n = 120) admitted to a single Level 1 academic trauma centre. Patients were expected to remain in the surgical intensive care unit for greater than 48 h. RESULTS: Patients had a mean age of 34.1+/- 16.0 years, a mean injury severity score (ISS) of 21.5 +/- 9.5, and were equally distributed by major injury type (48% blunt, 52% penetrating). One hundred and four patients (87%) received a total of 324 transfusions, 20 (6%) of which were given in the emergency room, 186 (57%) in the SICU, 22 (7%) post-SICU and 96 (30%) in the operating room. The mean volume of blood per patient transfused was 3144 +/- 2622 mL. One hundred and one patients received an allogeneic transfusion (mean volume 3126 +/- 2639 mL) and 10 patients received an autotransfusion (844 +/- 382 mL). The mean pre-transfusion Hb level was 9.1 +/- 1.4 g/dL. Transfusion volumes correlated with injury severity score (p = 0.011). Patients with an admission Hb < or =12 g/dL or age >55 years were at significant risk to receive increased transfusions (P < .001 and P = .035, respectively). An admission Hb < or =12 g/dL and any mention of long bone orthopedic operations or laparotomy or thoracotomy were associated with increased risk of blood transfusion during the first week of admission. Logistic regression analysis identified transfusion of >4 units of blood as a significant risk factor for SIRS. After 1 week of ICU stay, ISS > 20 and blunt injury were associated with increased risk of transfusion. CONCLUSIONS: Trauma patients are heavily transfused with allogeneic blood throughout the course of their hospital stay and transfusions are administered at relatively high pre-transfusion haemoglobin levels (mean of 9 g/dL). Transfusion of >4 units of blood is an independent risk factor for SIRS. Strategies to limit blood transfusions should be investigated in this population.     

Impact of pregnancy on the outcome of kidney transplantation

BACKGROUND: There is still controversy over whether pregnancy adversely affects renal transplantation outcomes. We, thus, compared two groups of kidney transplant recipients in terms of patient survival and allograft function: those who did versus did not conceive posttransplant. METHODS: This historical cohort study conducted between 1996 and 2002, divided female kidney transplant recipients of reproductive age into group I (n=86, at least one posttransplant pregnancy) and group II (n=125, no posttransplant pregnancy). The two groups were matched for age, cause of end-stage renal disease (ESRD), treatment protocol, and first creatinine (Cr). All patients received a first transplant and all had a Cr less than 1.5 mg/dL on entry into the study. The subjects were followed for 45.4 +/- 22.0 and 46.3 +/- 19.8 months, respectively (P>.05). Five-year patient and graft survivals and Cr were considered to be the main outcome measures. RESULTS: Mean (SD) age in groups I and II was 26.6 +/- 6.6 and 26.9 +/- 8.1 years, respectively (P>.05). Five-year patient and graft survival rates were not significantly different between the study groups. Of the women in group 1, only 9 (10.5%) subjects displayed elevated serum Cr levels (>1.5 mg/dL) at the end of follow-up, while the serum Cr levels in 35 (28%) group II patients were above 1.5 mg/dL (P=.024). CONCLUSION: Our results indicates pregnancy did not seem to adversely affect patient and graft survival among kidney transplant recipients. Renal transplantation in stable women of childbearing age should not be a contraindication to pregnancy.     

The impact of obesity on the outcomes of 1,153 critically injured blunt trauma patients

BACKGROUND: Several small series have had mixed conclusions regarding the impact of obesity on outcomes of trauma patients. The purpose of the present study was to evaluate a large cohort of critically injured patients to better understand the influence of obesity on the outcomes of patients after severe blunt trauma. METHODS: Retrospective review using the trauma registry and intensive care unit (ICU) database of all blunt trauma patients admitted to the ICU at our urban, Level I trauma center over a 5-year period (1998-2003). Obese patients (body mass index [BMI] > or = 30 kg/m) were compared with non-obese patients (BMI < 30 kg/m). RESULTS: There were 1,153 blunt trauma patients admitted to the ICU during the study period, including 283 (25%) obese (mean BMI = 35 +/- 6 kg/m) and 870 (75%) non-obese (mean BMI = 25 +/- 3 kg/m) patients. There was no difference between groups regarding age, sex, Injury Severity Score, or admission vitals. Obese patients had fewer head injuries (42 versus 55%; p = 0.0001) but more chest (45 versus 38%; p = 0.05) and lower extremity (53 versus 38%; p < 0.0001) injuries. There was no difference in the need for laparotomy, thoracotomy, or craniotomy. Obese patients suffered more complications (42 versus 32%; p = 0.002). Although there was only a trend toward higher mortality in obese patients (22 versus 17%; p = 0.10), stepwise logistic regression revealed obesity as an independent risk factor for mortality (odds ratio, 1.6; 95% confidence interval, 1.0-2.3; p = 0.03). Among survivors, obese patients required longer stays in the hospital (24 +/- 21 versus 19 +/- 17 days; p = 0.01), the ICU (13 +/- 14 versus 10 +/- 10 days; p = 0.005), and 2 more days of mechanical ventilation (8 +/- 13 versus 6 +/- 9 days; p = 0.07). CONCLUSION: Obese patients incur different injuries after severe blunt trauma than their non-obese counterparts. Despite sustaining fewer head injuries, obese patients suffer more complications, require longer stays in the hospital, more days of mechanical ventilation, and obesity is independently associated with mortality.     

Contrast material extravasation on contrast-enhanced helical computed tomographic scan of blunt abdominal trauma: its significance on the choice,time, and outcome of treatment

BACKGROUND: Contrast-enhanced helical computed tomographic (CT) scan of blunt abdominal trauma is valuable for detecting contrast material extravasation (CME). The aims of this study were to determine its significance and investigate factors associated with the choice, time, and outcome of management. METHODS: CT scans of 32 consecutive trauma patients who had CME were reviewed for the sources of CME, types of CME, flat inferior vena cava, and multiple abdominal injuries. The medical records were reviewed for demographics, systolic blood pressure, Injury Severity Score (ISS), choice of management, time interval between CT scan and intervention, and outcome of intervention. RESULTS: Systolic blood pressure < 100 mm Hg was the most important factor (p = 0.0064) that failed observational therapy. When proceeding to intervention treatment, patients with a flat inferior vena cava (1.6 +/- 1.1 hours) had a significantly shorter time interval between CT scan examination and intervention when compared with those with a normal cava (10.9 +/- 16.0 hours) ( p= 0.0124). The mortality rate after intervention treatment was 18.8%. High ISS, uncontained CME in the extraperitoneum, and multiple abdominal injuries were important risk factors. After adjusted for ISS and multiple abdominal injuries, the risk of dying from extraperitoneal CME remained significant when compared with intraperitoneal CME (adjusted odds ratio, 82.26; 95% confidence interval, 1.06-6,363.17). CONCLUSION: Termination of observational therapy was appropriate for trauma patients who had CME and systolic blood pressure < 100 mm Hg. The coexistence of a flat inferior vena cava and CME was associated with early intervention treatment. Despite early intervention, the mortality rate was 18.8%. High ISS and multiple abdominal injuries were important factors, but the risk of dying from uncontained extraperitoneal CME was 82 times the risk of dying from intraperitoneal CME.     

The adrenal response after severe trauma

BACKGROUND: The integrity of the hypothalamic-pituitary-adrenal axis is a major determinant of the host response to stress. Relative adrenal insufficiency has been implicated in poor outcome from systemic inflammatory states; however, whether low endogenous glucocorticoid levels are adaptive or pathologic remains controversial. The purpose of this study was to prospectively evaluate the cortisol response and determine the incidence of occult adrenal insufficiency after severe trauma. METHODS: Over an 18-month period, 22 severely injured patients admitted to the surgical intensive care unit of our level 1 trauma center were prospectively identified and followed. Demographic and outcome data were tabulated. In addition, random serum cortisol levels were obtained on days 0, 5, and 10 after injury. Relative adrenal insufficiency was defined as a random serum cortisol level less than 18 microg/dL. RESULTS: Mean baseline cortisol levels were elevated (35 +/- 3 microg/dL) and significantly declined over the next 10 days (day 5: 24 +/- 2 microg/dL; and day 10: 22 +/- 2 microg/dL; P <0.01). Thirteen of 22 (60%) patients had random serum cortisol levels less than 18 microg/dL. Only 1 of the 2 patients who died had a serum cortisol level less than 18 microg/dL. The mean cortisol levels at baseline were higher in the 2 patients who died compared with those who survived but this was not statistically significant (43.4 +/- 8.8 microg/dL versus 35.0 +/- 3.6 microg/dL, P = 0.5). CONCLUSIONS: Serum cortisol levels increased immediately and gradually returned towards normal after severe trauma. Occult adrenal insufficiency was common (60%) in this small group of severely injured patients. This did not, however, affect mortality in these patients. Further study is needed to delineate the role of occult adrenal insufficiency after severe injury.     

Hyperglycemia and outcomes from pediatric traumatic brain injury

BACKGROUND: The clinical significance of hyperglycemia after pediatric traumatic brain injury is controversial. This study addresses the relationship between hyperglycemia and outcomes after traumatic brain injury in pediatric patients. METHODS: We identified trauma patients admitted during a single year to our regional pediatric referral center with head regional Abbreviated Injury Scale scores > or = 3. We studied identified patients for admission characteristics potentially influencing their outcomes. The primary outcome measure was Glasgow Outcome Scale score. RESULTS: Patients who died had significantly higher admission serum glucose values than those patients who survived (267 mg/dL vs. 135 mg/dL; p = 0.000). Admission serum glucose > or = 300 mg/dL was uniformly associated with death. Admission Glasgow Coma Scale score (odds ratio, 0.560; 95% confidence interval, 0.358-0.877) and serum glucose (odds ratio, 1.013; 95% confidence interval, 1.003-1.023) are independent predictors of mortality in children with traumatic head injuries. CONCLUSION Hyperglycemia and poor neurologic outcome in head-injured children are associated. The pathophysiology of hyperglycemia in neurologic injury after head trauma remains unclear.     

Renal function after cardiac surgery: adverse effect of furosemide

Renal failure is a frequent event after cardiopulmonary by-pass. Hemodynamic alterations that occur during surgery, as well as factors depending on the host, are the main risk factors for renal dysfunction. To evaluate the frequency and risk factors for renal dysfunction in this setting, a cohort of fifty patients with preoperative serum creatinine under 1.5 mg/dL, submitted to cardiac surgery with cardiopulmonary by-pass was analyzed. Variables related to preoperative patient condition, intraoperative and postoperative periods were recorded. Renal function was assessed by clearances of creatinine, urea and free water, also by fractional excretion of sodium (FENa), at baseline, at anesthetic induction and during postoperative period. Patients were arbitrarily divided in two groups, according to the serum creatinine (S(Cr)) value at the end of the postoperative period: Group 1: S(Cr) < 2 mg/dL (n = 44 patients (88.5%)) and Group II: S(Cr) > 2 mg/dL (n = 6 patients (11.5%)). A decrease of renal function was observed in all patients: creatinemia raised from 1.04 +/- 0.2 to 1.55 +/- 0.4 mg/dL (33%), associated with a rise in FENa. Differences between group I and group II using univariate analysis were: baseline serum creatinine (1.01 +/- 0.23 mg/dL vs. 1.26 +/- 0.19 mg/dL, p = 0.03), FENa (0.99 +/- 0.8 vs. 2.2 +/- 2.1, p = 0.04), furosemide dose during surgery normalized to body surface area (93.2 +/- 23 mg/1.73 m2 BSA vs. 135 +/- 38 mg/1.73 m2 BSA, p < 0.001), and hemodilution index (17.3 +/- 4.3% vs. 22.8 +/- 3.2%, p < 0.01). In the multiple regression model, baseline creatinemia and furosemide dose were associated to renal dysfunction.     

Is elevated creatinine level a contraindication to endovascular aneurysm repair?

PURPOSE: It is widely believed that chronic renal insufficiency (CRI) greatly increases the risk associated with endovascular abdominal aortic aneurysm repair (EVAR) and is a relative contraindication to the procedure and to the use of intra-arterial contrast agents (IACA). We reviewed a 5-year EVAR experience to determine whether the procedure and use of IACA have an important deleterious effect on renal function in patients with and without pre-existing CRI. METHODS: Endovascular aneurysm repair (EVAR) was performed in 200 patients with a variety of endografts, with intra-arterial contrast agents. The patients were retrospectively assigned to three groups on the basis of preoperative serum creatinine concentration (Cr): group 1 (n = 108), Cr less than 1.5 mg/dL (normal range); group 2 (n = 65), Cr 1.5 to 2.0 mg/dL; group 3 (n = 27), Cr 2.1 to 3.5 mg/dL. No patients had undergone hemodialysis. In groups 2 and 3, patients received hydration perioperatively, and received mannitol intraoperatively; no nephrotoxic drugs were administered during the procedure, other than nonionic contrast agent (Omnipaque 350). RESULTS: The incidence of postoperative complications between the three study groups was not statistically different. In group 1 a transient increase in serum Cr (>30% over baseline and >1.4 mg/dL) was noted in three patients (2.7%), two of whom (1.9%) required temporary hemodialysis and one (0.9%) who died of renal failure. In group 2 a transient increase in serum Cr was noted in two patients (3.1%); both patients (3.1%) required temporary hemodialysis, and one patient (1.5%) died of renal failure. In group 3 a transient increase in serum Cr was noted in two patients (7.4%); one patient (3.7%) required temporary hemodialysis, and one patient (3.7%) died of renal failure. Perioperative hypotension significantly increased the risk for elevated serum Cr and death (P <.05), and larger contrast volume was associated with an increase in serum Cr (P <.05) during the postoperative period. CONCLUSIONS: EVAR with intra-arterial contrast agents can be accomplished in patients with chronic renal insufficiency who do not require dialysis, with limited and acceptable morbidity and mortality, similar to that observed with open aneurysm repair. Contrary to other reports in which perioperative precautions were not used, our study shows that with EVAR the risk for worsening renal failure, dialysis, and death is only slightly, and not significantly, greater in patients with preoperative chronic renal insufficiency compared with patients with normal renal function. Perioperative hypotension and increased contrast volume are significant risk factors for postoperative increase in serum Cr and death. With appropriate precautions such as averting perioperative hypotension and limiting the volume of nonionic contrast agents, elevated Cr need not be a contraindication to EVAR with intra-arterial contrast agents.     

The long-term effects of gastric bypass on vitamin D metabolism

OBJECTIVE: Alterations of the endocrine system in patients following Roux-en-Y gastric bypass (GBP) are poorly described and have prompted us to perform a longitudinal study of the effects of GBP on serum calcium, 25-hydroxy-vitamin-D (vitamin D), and parathyroid hormone (PTH). METHODS: Prospectively collected data were compiled to determine how GBP affects serum calcium, vitamin D, and PTH. Student t test, Fisher exact test, or linear regression was used to determine significance. RESULTS: Calcium, vitamin D, and PTH levels were drawn on 243 patients following GBP. Forty-one patients had long-limb bypass (LL-GBP), Roux >100 cm, and 202 had short-limb bypass (SL-GBP), Roux < or =100 cm. The mean (+/-SD) postoperative follow-up time was significantly longer in the LL-GBP group (5.7 +/- 2.5 years) than the SL-GBP group (3.1 +/- 3.6 years, P < 0.0001). When corrected for albumin levels, mean calcium was 9.3 mg/dL (range, 8.5-10.8 mg/dL), and no difference existed between LL-GBP and SL-GBP patients. For patients with low vitamin D levels (<8.9 ng/mL), 88.9% had elevated PTH (>65 pg/mL) and 58.0% of patients with normal vitamin D levels (> or =8.9 ng/mL) had elevated PTH (P < 0.0001). In individuals with vitamin D levels <30 ng/mL, 55.1% (n = 103) had elevated PTH, and of those with vitamin D levels > or =30 ng/mL 28.5% (n = 16) had elevated PTH (P = 0.0007). Mean vitamin D levels were lower in patients who had undergone LL-GBP as opposed to those with SL-GBP, 16.8 +/- 10.8 ng/mL versus 22.7 +/- 11.1 ng/mL (P = 0.0022), and PTH was significantly higher in patients who had a LL-GBP (113.5 +/- 88.0 pg/mL versus 74.5 +/- 52.7 pg/mL, P = 0.0002). There was a linear decrease in vitamin D (P = 0.005) coupled with a linear increase in PTH (P < 0.0001) the longer patients were followed after GBP. Alkaline phosphatase levels were elevated in 40.3% of patients and correlated with PTH levels. CONCLUSION: Vitamin D deficiency and elevated PTH are common following GBP and progress over time. There is a significant incidence of secondary hyperparathyroidism in short-limb GBP patients, even those with vitamin D levels > or =30 ng/mL, suggesting selective Ca malabsorption. Thus, calcium malabsorption is inherent to gastric bypass. Careful calcium and vitamin D supplementation and long-term screening are necessary to prevent deficiencies and the sequelae of secondary hyperparathyroidism.     

Natural history and outcomes of renal failure after trauma

BACKGROUND: The natural history of posttraumatic renal failure (PTRF) is not well-established. Overall prognosis and risk factors for need for dialysis in the setting of PTRF need more precise definition. STUDY DESIGN: We conducted a retrospective review of the trauma registry information from Los Angeles County-University of Southern California Medical Center from 1998 through 2005. PTRF was defined as the occurrence of serum creatinine > or = 2 mg/dL after admission for trauma. Clinical course and laboratory information from the trauma registry and ICU databases were analyzed. RESULTS: Of 33,376 trauma patients identified, PTRF developed in 323 (1%), with an overall mortality of 38% (n = 120). Onset of PTRF occurred an average of 4 +/- 7 days after admission, with average peak serum creatinine occurring 7 +/- 1 days after admission and only 56% (n = 180) of patients normalizing serum creatinine before discharge. A total of 64 patients (20% of renal failure patients, 0.2% of all trauma patients) required hemodialysis. The only independent risk factor for the need for dialysis was laparotomy, with patients manifesting an elevated creatinine later in their course more likely to require dialysis. Although injury severity correlated well with outcomes, the only independent risk factors for mortality in this population were persistently elevated serum creatinine and head Abbreviated Injury Score > 3. CONCLUSIONS: Development of PTRF in severely injured patients represents a substantial risk for morbidity and mortality in this population. Additional study is needed to determine the importance of delayed onset of PTRF, particularly in the setting of multiorgan failure, in determining outcomes.     

Relationship between fluid status and its management on acute renal failure (ARF) in intensive care unit (ICU) patients with sepsis: a prospective analysis

BACKGROUND: Sepsis carries a high morbidity and mortality, further enhanced by acute renal failure (ARF). Although fluid loading can prevent ARF in dehydrated patients, this approach could be risky in septic patients, since it can deteriorate oxygenation. This study evaluates the relationship between fluid status and management and ARF development in septic patients. METHODS AND PATIENTS: Patients admitted to the ICU between 1 January 2001 and 31 December 2001 were included if serum creatinine (Cr) was <2 mg% on admission, and if they developed sepsis. ARF was determined as a doubling of serum Cr, an increase of serum Cr >2 mg%, or oliguria <500 ml/24 hr. RESULTS: 257 out of 2442 patients, admitted to the intensive care unit (ICU), developed sepsis, 29 developed ARF, 13 needed a renal replacement. ARF vs. non-ARF patients were older (65.2 +/- 13.3 vs. 55.1 +/- 17.4, p=0.002), had a higher central venous pressure (CVP) at day 1 (9.6 +/- 4.3 vs. 5.2 +/- 3.6 mmHg, p<0.001), and at day 2 (7.1 +/- 5.1 vs. 5.1 +/- 4.0 mmHg, p=0.03), a higher colloid fluid loading for the first 3 days (2037 +/- 1681 vs. 1116 +/- 1220 mL, p<0.03), a higher serum Cr (1.25 +/- 0.39 vs. 0.96 +/- 0.33 mg/dL, p=0.009) and an increase vs. a decrease in serum Cr during the first 24 hr (+0.30 +/- 0.58 vs. -0.31 +/- 0.45 mg/dL, p=0.02), a lower diuresis (1347 +/- 649 vs. 1849 +/- 916 mL, p=0.005). There was no difference in APACHE II scores (19.2 +/- 7.2 vs. 17.2 +/- 6.6, p=0.1), or MAP (64.5 +/- 12.4 vs. 67.9 +/- 12.4, p=0.18). The fraction of inspired oxygen (FiO2) need in the ARF group increased from 40.4 +/- 11.5 to 65.6 +/- 24.2% from day 1 to day 2 (p=0.04), where it remained unchanged in the non-ARF group. The use of diuretics was higher in the ARF group (21/29 vs. 43/228, p=0.001). CONCLUSION: Septic patients developing ARF have an elevated CVP at day 1 of sepsis, indicating cardiodepression or intrarenal causes for hypoperfusion. These patients develop ARF despite further fluid loading. Respiratory function deteriorated in patients with ARF. Persistent fluid challenges should be avoided if they do not lead to an improvement in renal function, or if oxygenation deteriorates.     

Predictors of outcome in patients requiring surgery for liver trauma

INTRODUCTION: Severe bleeding from liver injury is one of the major causes of mortality in patients with abdominal trauma. The study was undertaken to assess factors that influence outcome following liver trauma. PATIENTS AND METHODS: This is a prospective study of patients with liver injury treated in one surgical ward at King Edward VIII Hospital over a 7-year period (from 1998 to 2004). Data collected included demographics, intra-operative findings, operative management and outcome. RESULTS: Of a total of 478 patients with abdominal trauma, 105 (22%) were found to have liver injuries, of whom only 7 were female. Their mean age was 27.81+/-10.33 years. Injuries were due to firearms (70), stabs (26) and blunt trauma (9). Nineteen patients presented with shock (systolic BP6h in 47 patients. Forty patients required ICU management (38%) and the mean ICU stay was 6.55+/-5.65 days. Twenty patients (19%) needed a re-laparotomy for various reasons. The complication rate was 37% and the mortality rate was 20% (23% for firearms, 44% for blunt trauma and 4% for stabs). The mortality rate in patients with shock was 58% compared to 12% in those who were not shocked (p<0.0001). Mortality rate was 2, 23 and 63% for Injury Severity Score (ISS)20, respectively (group 1 versus group 2 p=0.015; group 1 versus group 3 p<0.0001 and group 2 versus group 3 p=0.001). Mortality rates for delay 6h were 28 and 9%, respectively (p=0.008). Associated injuries led to a higher mortality (3% versus 27%; p=0.006). Hospital stay was 11.27+/-12.09 days. CONCLUSIONS: Liver injuries occurred in 22% of abdominal injuries. Injury mechanism, delay before surgery, shock on admission, grade of injury, associated injury and ISS are significantly associated with outcome.     

Management of adult blunt splenic injuries: comparison between level I and level II trauma centers

BACKGROUND: The factors important in determining outcome when managing adult blunt splenic injuries continue to be debated. Whether trauma center level designation (Level I versus Level II) affects patient management has not been evaluated. STUDY DESIGN: We conducted a retrospective analysis of prospectively gathered data from the Pennsylvania Trauma Outcome Study database that collected information from 27 statewide trauma centers (Level I [15], Level II [17]). Adult patients (ages > or = 16 years) with blunt splenic injuries (ICD-9-CM 865) were evaluated. Demographic data, injury data, and trauma center level designation were collected, and patient management, length of stay, and mortality were analyzed. RESULTS: There were 2,138 adult patients who suffered blunt splenic injuries during the study period (1998-2000). Patients treated at Level II trauma centers (n = 772) had a higher rate of operative treatment (38.2% versus 30.7%) (p < 0.001), but a shorter mean length of stay (10.1 +/- 0.4 versus 12.0 +/- 0.4 days) (p < 0.01) compared with patients in Level I trauma centers (n = 1,366). The rate of failure of nonoperative treatment was lower at Level II trauma centers (13.0% versus 17.6%) (p < 0.05), but the mortality for patients managed nonoperatively was higher (8.4% versus 4.5%) (p < 0.05). Splenorrhaphy was performed more frequently in Level I trauma centers. CONCLUSIONS: Management differences exist in the treatment of adult blunt splenic injuries between institutions of different trauma center level designation. Multicenter studies should account for this finding in design and implementation.     

A prospective,randomized, open labeled crossover trial of fosinopril and theophylline in post renal transplant erythrocytosis

Angiotensin converting enzyme inhibitors (ACEI) and theophylline have been reported to decrease the elevated hemoglobin (Hgb) and hematocrit (Hct) levels in the renal transplant recipients with erythrocytosis. We conducted a prospective randomized, open labeled, crossover trial with theophylline, and an ACEI, fosinopril in nine stable renal transplant recipients with erythrocytosis. Aim of the study was to determine and compare the efficacy of these medications in stable renal transplant patients. At three months, compared to baseline, fosinopril significantly reduced the elevated hemoglobin (Hgb 17.2 +/- 0.6 vs. 14.9 +/- 1.4 gm/dL, p = 0.0023), and hematocrit levels (Hct 51.3 +/- 2.4 vs. 43.7 +/- 4.6%, p = 0.003). In contrast theophylline therapy was associated with a non-significant rise in hemoglobin (17.4 +/- 0.7 vs. 18.1 +/- 0.9gm/dL, p > 0.05) and hematocrit (52.4 +/- 2.7 vs. 54.7 +/- 3.9%, p > 0.05). With fosinopril compared to theophylline, there was a significant difference in the change in hemoglobin (baseline to three months 2.8 +/- 1.7 vs. -0.7 +/- 0.69 gm/dL respectively, p = 0.017), and the change in hematocrit (baseline to three months 9 +/- 6 vs. -2.3 +/- 2.7% respectively, p = 0.027). Four patients (44.4%) did not tolerate theophylline and did not complete the theophylline arm. To conclude, in our study, fosinopril effectively decreased the elevated hemoglobin and hematocrit in patients with post transplant erythrocytosis, and was superior to theophylline, while theophylline was ineffective and poorly tolerated in this condition.     

Nephrotoxicity of low-osmolality versus iso-osmolality contrast agents: impact of N-acetylcysteine

BACKGROUND: Recent data support that iodixanol, an iso-osmolality contrast agent, is less nephrotoxic than low-osmolality contrast agents when hydration is the only prophylactic strategy used. We evaluated the nephrotoxicity of iso- and low-osmolality contrast agents with prophylactic administration of N-acetylcysteine (NAC) along with hydration. METHODS: Two hundred and twenty-five patients with chronic renal insufficiency (serum creatinine >1.5 mg/dL or an estimated glomerular filtration rate <60 mL/min/1.73 m(2)), referred to our institution for coronary and/or peripheral procedures, were assigned to receive low-osmolality (iobitridol group; N = 115) or iso-osmolality (iodixanol group; N = 110) contrast dye. In all cases prophylactic administration of 0.45% saline intravenously and NAC (1200 mg orally twice daily) was used. RESULTS: Baseline creatinine levels were similar in the 2 groups [iobitridol group = 1.70 (IQR: 1.54-1.98) mg/dL; iodixanol group = 1.73 (IQR: 1.56-2.00) mg/dL, P = 0.33]. The risk score for contrast nephrotoxicity was 5.0 +/- 1.6 in the iobitridol group versus 5.0 +/- 1.8 in the iodixanol group (P = 0.44). Increase of at least 0.5 mg/dL of the creatinine concentration 48 hours after the procedure occurred in 4/115 patients (3.5%) in the iobitridol group and 3/110 patients (2.7%) in the iodixanol group (P = 1.00; OR 0.78; 95% CI 0.17-3.56). Amount of contrast media administration was similar in the 2 groups (iobitridol group = 167 +/- 90 mL; iodixanol group = 164 +/- 82 mL; P = 0.61). CONCLUSION: Nephrotoxicity of iso-osmolality and low-osmolality contrast agents was similar when a prophylactic strategy of hydration plus NAC was utilized.     

Anemia and blood transfusion in trauma patients admitted to the intensive care unit

BACKGROUND: Anemia is a common occurrence in the intensive care unit (ICU). Although resuscitation, including the use of blood, is a mainstay of early treatment of trauma victims, the safety and efficacy of red blood cell (RBC) transfusion has come under scrutiny recently. The issue of blood use in critically injured patients requires evaluation. METHODS: This was a post hoc analysis of a subset of trauma patients (> or =18 years in age) from a prospective, multicenter, observational, cohort study in the United States. Patients were enrolled within 48 hours after ICU admission and followed for up to 30 days, or until hospital discharge or death. RESULTS: Five hundred seventy-six patients from 111 ICUs in 100 hospitals were enrolled between August 2000 and April 2001. At baseline, mean age was 44.1 +/- 20.2 years, 73.6% were men, and mean APACHE II score was 16.9 +/- 8.2. Mean baseline hemoglobin was 11.1 +/- 2.4 g/dL and patients remained anemic throughout the study either with or without transfusion; 55.4% of patients were transfused (mean, 5.8 +/- 5.5 units) during the ICU stay and 43.8% of patients had an ICU length of stay > or = 7 days. Mean pretransfusion hemoglobin was 8.9 +/- 1.8 g/dL. Mean age of RBCs transfused was 20.1 +/- 11.4 days. As compared with the full study population, patients in the trauma subset were more likely to be transfused and received an average of 1 additional unit of blood. CONCLUSION: Anemia is common in critically injured trauma patients and persists throughout the duration of critical illness. These patients receive a large number of RBC transfusions during their ICU course with aged blood.     

Rapid communication: chronic renal insufficiency after laparoscopic partial nephrectomy and radical nephrectomy for pathologic t1a lesions

PURPOSE: To report the prevalence of new-onset renal insufficiency in patients undergoing laparoscopic partial nephrectomy (LPN) as compared to laparoscopic radical nephrectomy (LRN) for pathologic T1a lesions. PATIENTS AND METHODS: Forty-eight patients and 37 patients with a normal contralateral kidney, preoperative creatinine (Cr) concentration <2 mg/dL, and tumors <4 cm in size underwent LPN and LRN, respectively. Glomerular filtration rate (GFR) was estimated using an abbreviated Modification of Diet in Renal Disease (MDRD) equation. Cr concentrations and GFR values were analyzed in patients undergoing LPN or LRN. Statistical analysis was performed with two-tailed t-test assuming unequal variances, to establish significance by P < 0.05. RESULTS: Preoperative Cr and GFR was equivalent in the LPN and LRN groups (0.9 mg/dL and 90 mL/min). At last follow-up (mean 205 and 233 days in the LPN and LRN groups, respectively) mean creatinine was 1.03 +/- 0.3 mg/dL v 1.4 mg/dL +/- 0.3 (P = 0.0002). Estimated GFR was 79 +/- 22 mL/min per 1.73 m2 v 55 +/- 14 mL/min per 1.73 m2 (range 31-91 mL/min per 1.73 m2; P < .0001) in the LPN and LRN groups, respectively. One patient in the LPN group and three patients in the LRN group had clinical renal insufficiency as defined by Cr > 2.0 mg/dL. Subclinical renal insufficiency (Cr < 2.0, but calculated GFR <60 mL/min per 1.73 m2) was present in 57% of the LRN patients v 15% of the LPN patients. CONCLUSIONS: LPN preserves renal function more effectively than LRN for pathologic T1a lesions. Subclinical renal insufficiency (GFR <60 mL/min per 1.73 m2) was present in the majority of patients undergoing radical nephrectomy in our series. Importantly, this series included the use of warm ischemia in all cases.