Development and validation of an automated, enzyme-mediated colorimetric assay of salicylate in serum

This salicylate-specific assay can be adapted for use with most discrete analyzers, for rapid emergency or routine testing with small serum or plasma sample volumes and a single calibration. The basis of this method is as follows: salicylate monooxygenase (EC 1.14.13.1) converts salicylate to catechol in the presence of NADH; the catechol then reacts with 4-aminophenazone under alkaline conditions, catalyzed by manganese ions, to produce a red dye. Incorporation of an NADH-regenerating system, involving glucose and glucose dehydrogenase, into the enzyme reagent ensures that the working reagent is stable for more than two weeks. The standard curve is linear over the drug concentration range 0 to 5 mmol/L. The CV was less than 4% over 20 days. Results correlated well with those by the Trinder colorimetric method and an HPLC method. We saw no interference by any of 80 drugs we tested at therapeutic concentrations or by endogenous compounds in serum.     

Salicylate determined with a microcentrifugal analyzer, and compared with Du Pont aca, trinder, and liquid-chromatographic methods

We describe a new automated method for measuring serum salicylate in the Multistat III microcentrifugal analyzer. Ferric nitrate reagent and serum blanking are used. We compare this new method, the automated Du Pont aca method, and the manual Trinder method with a "high-performance" liquid-chromatographic method. The unblanked Trinder method had the poorest correlation (r = 0.980, Sy X x = 19.1) with the chromatographic method. The serum-blanked aca and Multistat III methods showed better correlation (r = 0.995, Sy X x = 9.5 mg/L, and r = 0.991, Sy X x = 13.0 mg/L, respectively) with the chromatographic method. However, we conclude that all three colorimetric methods give clinically useful results and that the increased time, expense, and expertise required for chromatographic salicylate analysis are difficult to justify in a routine clinical laboratory.     

Lactic acidosis and acute ethanol intoxication

Ethanol intoxication has been widely reported as a cause of lactic acidosis. To determine the frequency and severity of ethanol-induced lactic acidosis, patients who presented to an emergency department with a clinical diagnosis of acute ethanol intoxication and a serum ethanol concentration of at least 100 mg/dL were studied. Arterial blood was sampled for lactate and blood gas determinations. A total of 60 patients (mean age, 41 years) were studied. Twenty-two patients sustained minor trauma. Ethanol concentrations ranged from 100 to 667 mg/dL (mean, 287 mg/dL). Lactate concentrations were abnormal (>2.4 mmol/L) in seven patients (11.7%). In all cases, blood lactate was less than 5 mmol/L. Of the patients with elevated lactate, other potential causes for lactic acidosis, including hypoxia, seizures, and hypoperfusion, were also present. Only one case with elevated blood lactate concentration had associated acidemia. Significant elevations of blood lactate are uncommon in acute ethanol intoxication. In patients with ethanol intoxication who are found to have lactic acidosis, other etiologies for the elevated lactate level should be considered.     

Mechanical ventilation was associated with acidemia in a case series of salicylate-poisoned patients

OBJECTIVES: Despite little empiric evidence, mechanical ventilation (MV) in the setting of salicylate poisoning is considered by many to be harmful. When salicylate-poisoned patients are ventilated at conventional settings, the respiratory alkalosis is abolished, more salicylate is able to pass into the central nervous system (CNS), and neurotoxicity worsens. The objective of this study was to identify a relationship between MV, acidosis, and outcome in salicylate-poisoned patients. METHODS: The authors electronically searched a poison control center (PCC) database (2001-2007) for patients with salicylate poisoning, defined as a serum concentration > 50 mg/dL, who had MV listed as a therapy. For the 7-year study period, a total of 3,144 salicylate-poisoning cases were identified. Eleven patients met the inclusion criteria of having both salicylate concentrations > 50 mg/dL and required MV; only 7 of them had post-MV data available. RESULTS: In all seven patients with post-MV blood gas data, the post-MV pH was < 7.4. In five of six patients with recorded PCO2, the post-MV PCO2 was > 50 mm Hg. Two of the seven patients in the study group died following intubation (two patients died within 3 hours [serum salicylate concentrations, 85 and 79 mg/dL, respectively]). Another patient sustained severe neurologic injury (serum salicylate concentration, 84 mg/dL). The other four patients were ultimately discharged home. In the three patients with the worst clinical outcome, deterioration was reported within hours of intubation. CONCLUSIONS: Inadequate MV of patients with salicylate poisoning is associated with respiratory acidosis, acidemia, and clinical deterioration in this series of cases. This supports warnings about the danger of improper MV in patients with salicylate poisoning. A prospective study should be performed.     

Effect of Intravenous Albumin Infusion on Brain Salicylate Concentration

Background: Salicylate poisoning appears to result in death, despite supportive care, once a critical brain salicylate concentration is reached. The binding of salicylate to albumin is saturable; free plasma salicylate concentrations rise disproportionately to total drug levels. Because unbound salicylate distributes into the brain, the authors questioned whether an intravenous (IV) infusion of albumin would cause a redistribution of salicylate from the brain back into the plasma, which might allow enough time for hemodialysis to be instituted. Objectives: To determine if IV albumin infusion would lower brain salicylate concentrations through redistribution in a porcine model of acute salicylate poisoning. Methods: In a randomized controlled trial, 17 swine under anesthesia and controlled ventilation received 400 mg/kg of sodium salicylate IV over 15 minutes. At 60 minutes, nine animals received 1.25 g/kg albumin (25% solution) IV over 15 minutes, while eight control animals received an equal volume of normal saline (5 mL/kg). Arterial pH was maintained between 7.45 and 7.55. Serial measurements of serum albumin as well as free and total salicylate concentrations were obtained, and urine was collected for measurement of total salicylate excretion. At 180 minutes, animals were killed and brains harvested for measurement of brain salicylate concentrations. Results: Average peak serum total salicylate concentrations of 105.5 and 109 mg/dL were achieved in control and albumin‐treated animals, respectively. Albumin infusion was accompanied by statistically significant increases in serum total salicylate concentrations (median from 79.5 to 86.9 mg/dL at 75 minutes), while levels decreased slightly in control animals. Serum free salicylate concentrations decreased slightly in albumin‐treated animals, but the difference was not statistically significant. Median brain salicylate concentrations were about 14% lower in the albumin treatment group (17.8 mg/100 g brain) compared with controls (20.5 mg/100 g brain); this approached statistical significance (p = 0.075). Median urinary salicylate excretion was higher in the albumin‐treated group (0.83 vs. 0.48 g; p = 0.072), with similar urinary pH and volumes in both groups. Conclusions: In this animal model of salicylate poisoning, IV infusion of 1.25 g/kg albumin was accompanied by a 14% decline in median brain salicylate concentrations, which approached statistical significance.     

Death Due to Acute Salicylate Intoxication Despite Dialysis

Background: Salicylate poisoning is a common problem with appreciable morbidity and mortality. We present a case of a patient with a large aspirin ingestion who expired despite aggressive hemodialysis (HD). Case Report: A 35-year-old man arrived at the Emergency Department 7.5 h after ingesting 400 tablets of 325-mg aspirin. He was afebrile, the respiratory rate (RR) was 30 breaths/min, heart rate (HR) 120 beats/min, blood pressure (BP) 125/76 mm Hg, and oxygen saturation 99% on room air. His salicylate concentration was 89.6 mg/dL. His initial arterial blood gas: pH 7.48, pCO₂ 21 mm Hg, PaO₂ 97 mm Hg, and bicarbonate 15.8 mmol/L. His initial serum chemistry panel was normal. He received activated charcoal and intravenous hydration with sodium bicarbonate. Two hours after arrival, salicylate concentration was 91.6 mg/dL. The patient became agitated and HD was initiated; 22 h after presentation, repeat salicylate concentration was 88.4 mg/dL and his creatinine was 3.9 mg/dL. A second run of HD was performed. After this, his temperature had risen to 39.06°C (102.3°F), BP 122/64 mm Hg, HR 168 beats/min, RR 43 breaths/min, and oxygen saturation 95% (2 L nasal cannula). His confusion increased, and he died 40 h after his ingestion. Conclusion: HD is widely advocated in managing severe salicylate intoxications, however, no consensus exists for the duration and best mode of therapy. Patients with severe salicylate poisonings may require extended durations of HD to effectively mitigate toxicity. Additional study is warranted to determine optimal therapy in severe salicylate intoxications.     

The Saliva Strip Test Is an Accurate Method to Determine Blood Alcohol Concentration in Trauma Patients

OBJECTIVES: To determine the accuracy of alcohol saliva testing (AST) in trauma patients. METHODS: Blood alcohol concentration (BAC) was measured by using both AST (QED A350; STC Technologies, Bethlehem, PA) and blood serum levels in 100 trauma patients admitted to the emergency department of an urban Level 1 trauma center. RESULTS: All 41 patients who tested positive for BAC on AST (mean [+/-SD]: 167.9 +/- 16.16; range: 20-350 mg/dL) also tested positive on serum determination (mean: 197.6 +/- 13.79; range: 22-446 mg/dL). Correlation between the two positive tests was significant (0.879, p < 0.001). Of the remaining 61 patients, 59 tested negative on both tests, while two patients with BACs of <30 mg/dL tested negative on the AST. For 18 patients with blood in the oropharynx, there was a correlation of 0.976 (p < 0.001, two-tailed) between serum and AST tests. CONCLUSIONS: The AST method of measuring BAC in trauma patients is accurate. Blood in the oral cavity did not appear to affect the accuracy of the test.     

An assessment of the radial diffusion method for the measurement of pepsin in gastric secretion and its comparison with the haemoglobin substrate colorimetric method.

The radial diffusion method of pepsin assay has been compared with a modified Anson-Mirsky colorimetric method. Though claimed to measure accurately over a wide range, we found that the assay range of the radial diffusion method was only 10 to 100 mg/l; even with these narrow limits, it was inaccurate. In contrast, the colorimetric method was much more rapid, sensitive and could accurately measure a wide range of 0.5 to 500 mg/l. The colorimetric technique is therefore the superior method.     

Confirmation of serum salicylate levels in Reye's syndrome: a comparison between the Natelson colorimetric method and high performance liquid chromatography

Serum was obtained from 11 patients with Reye's syndrome at admission and analyzed for the presence of salicylates by the Natelson colorimetric technique and high performance liquid chromatography. Salicylate levels obtained by the Natelson method had a mean of 6.00 mg/dl +/- 4.58; the mean HPLC salicylic acid level was 5.09 mg/dl +/- 5.14. The correlation coefficient was 0.985 with a linear regression line y = 0.8788x + 1.527. No other salicylate metabolites nor interfering substances were identified. Once the accuracy of the Natelson method was confirmed, the charts of 82 patients were reviewed for admission salicylate levels. The overall mean was 8.63 mg/dl (survivors, 8.45 mg/dl +/- 8.56; fatalities, 9.28 mg/dl +/- 5.34). There was no correlation found between admission salicylate level and peak ammonia level, another important index of disease severity.     

Delayed salicylate toxicity at 35 hours without early manifestations following a single salicylate ingestion

OBJECTIVE: To report a case of delayed toxicity following a single ingestion of aspirin, where the initial concentrations were nearly undetectable and the patient was completely asymptomatic for the first 35 hours. CASE SUMMARY: A 14-year-old white female was evaluated after a single ingestion of 120 tablets of aspirin 81 mg/tablet hours before arrival to the emergency department. She denied nausea, abdominal pain, tinnitus, or shortness of breath. She received one dose of activated charcoal. The first salicylate concentration (4 h after ingestion) was 1 mg/dL. At 35 hours, the patient became symptomatic (dizziness, tinnitus, epigastric discomfort). Her salicylate concentration at that time was 46 mg/dL. A second dose of activated charcoal was administered, and intravenous bicarbonate with potassium was started as a continuous infusion for 30 hours. DISCUSSION: While delayed salicylate toxicity is well reported in the literature, no report was found regarding concentrations increasing to toxicity 35 hours after ingestion. The delayed aspirin absorption may be due to salicylate-induced pylorospasm or the formation of pharmacobezoars. CONCLUSIONS: In cases with known salicylate ingestion, it is important to follow salicylate concentrations every 4 hours until they are steadily decreasing according to a 4-hour half-life and the patient shows no symptoms of salicylate intoxication.     

Cardiac Arrhythmias and ECG Abnormalities in Tricyclic Antidepressant Overdose

Background. Ethanol used as an antidote is said to have various adverse effects, particularly in children. The rate of these adverse effects is not known.

Methods. Twenty-one-year retrospective chart review (1980–2000) from suspected methanol poisoning patients treated with ethanol in two large pediatric tertiary care centers.

Results. A total of 60 children (median age of 24 months) received ethanol for suspected methanol poisoning: 39 orally and 21 intravenously. Median initial methanol level was 4.16 mmol/L (13.3 mg/dL) (range 0 to 87.5 mmol/L or 0 to 280 mg/dL). Median duration of ethanol treatment was 16 hours (range 1.5 to 72 hours). None [0% (95% CI 0–5%)] of the 60 patients developed symptomatic hypoglycemia. Of the 50 patients that had a glucose level measured, none [(0% [95% CI 0–6%)] had a serum glucose concentration <2.78 mmol/L (<50 mg/dL). Eight patients [16% (95% CI 8–30%)] had at least one serum glucose concentration between 2.78–3.61 mmol/L (50–65 mg/dL), but none of those had symptoms compatible with hypoglycemia. A total of 42 patients [84% (95% CI 70–92%)] had all their serum glucose concentrations >3.61 mmol/L (>65 mg/dL). There was no identifiable difference in the glucose intake between the serum glucose concentration groups. Six out of the 60 patients [10% (95% CI 4–21%)] were described as more drowsy after ethanol but none was comatose or needed intubation. No child showed signs of hypothermia [0/40 (95% CI 0–8%)] (rectal temperature <35°C), hepatotoxicity (0/12) (AST or ALT>100 U/L) or even thrombophlebitis (0/21). None of the 22 patients with toxic levels of methanol (≥6.2 mmol/L–≥20 mg/dL) died or had ethanol-induced morbidity despite wide variation in ethanol levels.

Conclusion. The rate of clinically important adverse effects related to ethanol used as an antidote to treat methanol poisoning in children was either absent or low in a tertiary care pediatric hospital setting. There was no morbidity or mortality associated with ethanol when it was used despite wide variation in ethanol levels. These results suggest that with appropriate monitoring and intravenous glucose intake in a controlled environment such as a pediatric intensive care unit, ethanol therapy does not carry as many risks as currently believed.     

Interlaboratory evaluation of salicylate interference in colorimetric acetaminophen methods and its clinical significance

Serum specimens with concentrations simulating an overdose of salicylate and acetaminophen were submitted to laboratories participating in an external quality-control program, to evaluate both the magnitude of salicylate interference in colorimetric acetaminophen methods and the clinical significance of the interference. The apparent acetaminophen concentration determined by nitration methods was increased by about 0.70 mg/L per milligram of salicylate per deciliter. Of those laboratories using nitration procedures, 25% do not routinely correct for salicylate and 66% use the (incorrect) correction factor provided by a kit manufacturer. Laboratory data, as they would have been reported to physicians, were used to estimate the acetaminophen half-life and were also applied to a nomogram used to assess the probability of hepatotoxicity. Interference by salicylate in the simulated overdose of 10 g (total dose) of each drug falsely indicated impending hepatic necrosis unless the appropriate correction factor was used. Laboratories using nitration procedures should screen samples submitted for acetaminophen assay for the presence of salicylate and, if present, either use a method specific for acetaminophen or utilize a correction factor determined in-house.     

CLINICAL ASSESSMENT OF AN ENZYME IMMUNOASSAY (EMIT) FOR MEASUREMENT OF SERUM SALICYLATE

Salicylic acid concentrations in serum were compared using a homogenous enzyme immunoassay (EMIT) and an automated colorimetric analysis (ACA) technique. Analysis of samples showed similar within-day and day-to-day coefficients of variation (CV): 1.3% and 4.6% by EMIT and 1.0% and 2.6% by ACA, respectively. Quantification of serum containing added salicylate and serum from patients receiving salicylate therapy showed a slight positive bias towards the ACA method over the range of 0-600 mg/l. No significant difference in reliability was found between the two methods. The EMIT assay showed no interference from other antiflammatory drugs being taken by patients who were not taking salicylates. If decisions to alter salicylate dosage are made with due regard to the drug's saturation kinetics, measurements using either EMIT or ACA should allow the clinician to titrate patients' serum concentrations accurately within the narrow therapeutic range.     

Accuracy and Test Characteristics of Ancillary Tests of Cerebrospinal Fluid for Predicting Acute Bacterial Meningitis in Children with Low White Blood Cell Counts in Cerebrospinal Fluid

Objectives: To determine whether ancillary tests of cerebrospinal fluid (CSF), specifically, the total protein concentration, glucose concentration, and percent neutrophils, provide information for diagnosing acute bacterial meningitis among children with low white blood cell (WBC) count in CSF. Methods: The authors retrospectively reviewed CSF from children aged 1 month to 18 years undergoing lumbar puncture at Children's Hospital in Boston from 1993 to 1999. Data were supplemented with CSF test results obtained from children with 0–30 WBCs/mm³ in CSF diagnosed with acute bacterial meningitis at the same institution from 1984 to 1992. For each test, the incremental value of ancillary tests was estimated by calculating indices of performance such as the area under receiver operator characteristic curves (AUC) and interval likelihood ratios that are relatively insensitive to disease prevalence. Results: Among children with 0–30 WBCs/mm³ in CSF who met study criteria, acute bacterial meningitis was identified in ten of 7,701 (0.1%) for the period from 1993 to 1999 and supplemented with 11 additional cases for the period from 1984 to 1992. AUC values for ancillary tests were 0.61 for total protein concentration, 0.69 for glucose concentration, and 0.90 for percent neutrophils. Interval likelihood ratios were unremarkable for mildly abnormal test results. In contrast, interval likelihood ratios for markedly abnormal test results were higher: 22 for total protein concentration >120 mg/dL, 57 for neutrophils >75%, 15 for glucose concentration <20 mg/dL, and 20 for glucose concentration >120 mg/dL. Conclusions: When markedly abnormal, results of CSF total protein concentration, glucose concentration, and percent neutrophils have value for diagnosing acute bacterial meningitis, even among children with a low WBC count in CSF.     

Accuracy of an Enzymatic Assay Device for Sermn Ethanol Measurement

Objective: To determine the accuracy of an enzymatic assay of serum to measure blood ethanol levels in the emergency department. Methods: A blinded, prospective study of emergency department patients for whom a blood ethanol was ordered and performed. After skin prep with betadine, two blood samples were drawn into separate sodium fluoride-containing vacutainers. One sample was sent to the hospital laboratory for blood ethanol analysis. The other was centrifuged for 5 minutes and the serum was then assayed using the QED A350′ Saliva Alcohol Test. Values were then compared by kappa statistic and Pearson's correlation. Sensitivity and specificity calculations were determined for the QED device to detect a blood ethanol > 100 mg/dL. Results: Sixty-six patients were enrolled. The kappa value for QED compared to lab blood ethanol was 0.93. The Pearson's correlation coefficient was 0.94. The QED, in general, tended to overestimate blood ethanol slightly. The QED was 100% sensitive and 82% specific in detecting a blood ethanol > 100 mg/dL. Conclusions: Analysis of serum using a QED A350′ is a sensitive and accurate index of low to moderate increases in blood ethanol appropriate to emergency department, but not legal, interpretation.     

False Positive Acetaminophen Levels Associated with Hyperbilirubinemia

Serum acetaminophen determination is frequently necessary in patients with hepatic failure. We observed two patients (#1, #2) with elevated serum total bilirubin levels (26.5 mg/dL and 40.1 mg/dL) who had multiple false positive acetaminophen levels using the kinetic method of the GDS Diagnostics enzymatic acetaminophen assay (GDS Diagnostics, Elkhart, IN). We investigated the magnitude, threshold, and linearity of this effect using the GDS Diagnostics assay and an EMIT acetaminophen assay on two other hyperbilirubinemic patients (#3, #4) and a commercial solubilized bilirubin standard. Samples were diluted using fresh frozen plasma, and acetaminophen levels were analyzed twice using the kinetic method of the GDS Diagnostic acetaminophen assay and twice with the EMIT assay. The absence of acetaminophen in all samples was verified by gas chromatography/mass spectroscopy (GC/MS). The kinetic GDS assay resulted in a positive acetaminophen assay (cutoff for a positive result = 10 mg/L) with patient #3, patient #4, and in the bilirubin standard when the total bilirubin levels were 28.2 mg/dL, 22.5 mg/dL, and 18.3 mg/dL, respectively. One sample was interpolated to give a positive acetaminophen reading when diluted to a total bilirubin concentration of 15 mg/L. None of the samples tested with GC/MS or the EMIT assay resulted in any detectable acetaminophen. In conclusion, caution must be taken utilizing the GDS Diagnostic assay for the quantification of acetaminophen with concomitant hyperbilirubinemia. Alternatives such as EMIT or GC/MS should be employed to assess acetaminophen levels in such patients.     

Comparison of four digoxin immunoassays with respect to interference from digoxin-like immunoreactive factors

Objectives: Comparison of a new monoclonal digoxin assay with three polyclonal digoxin assays for their cross-reactivity to digoxinlike immunoreactive factors (DLIF) and digoxin metabolites.

Design and Methods: Sixty-:six nondigitalized patient samples from 5 different groups: neonates, women in 3rd trimester pregnancy, and patients with liver or renal diseases, or undergoing organ transplants, and 139 samples from digoxin-treated patients of 4 categories (hospital sick, liver, renal, and outpatients) were compared in 4 different digoxin assays: (a) ACS™ Digoxin (ACS) developed for the automated chemiluminescent Ciba Corning ACS 180^® system, (b) Baxter Stratus™ (Stratus, a fluoroimmunoassay), (c) Ciba-Corning Magic^TM (Magic, a radioimmunoassay), and (d) an in-house radioimmunoassay (RIA). The ACS^TM and RIA were also compared for their cross-reactivity to four principal digoxin metabolites.

Results and Conclusion: Among the nondigitalized specimens, no significant DLIF interference was found for all 4 assays among the pregnant women or liver and transplant patients. However, the neonates registered high DLIF interference with Magic™ and RIA, but none for ACS™ or Stratus™. DLIF interference in renal samples was highest in the Magic assay and lowest in RIA. Among the specimens with digoxin, a higher number of discrepant samples were found from the sick patients than from outpatients. In 75% of such discrepant samples, the ACS™ result was less than other assay results, suggesting DLIF as the probable cause. The two assays differed most in their cross-reactivity to the deglycated metabolites, digoxigenin and its mono-digitoxoside.     

False positive acetaminophen levels associated with hyperbilirubinemia

Serum acetaminophen determination is frequently necessary in patients with hepatic failure. We observed two patients (#1, #2) with elevated serum total bilirubin levels (26.5 mg/dL and 40.1 mg/dL) who had multiple false positive acetaminophen levels using the kinetic method of the GDS Diagnostics enzymatic acetaminophen assay (GDS Diagnostics, Elkhart, IN). We investigated the magnitude, threshold, and linearity of this effect using the GDS Diagnostics assay and an EMIT acetaminophen assay on two other hyperbilirubinemic patients (#3, #4) and a commercial solubilized bilirubin standard. Samples were diluted using fresh frozen plasma, and acetaminophen levels were analyzed twice using the kinetic method of the GDS Diagnostic acetaminophen assay and twice with the EMIT assay. The absence of acetaminophen in all samples was verified by gas chromatography/mass spectroscopy (GC/MS). The kinetic GDS assay resulted in a positive acetaminophen assay (cutoff for a positive result= 10 mg/L) with patient #3, patient #4, and in the bilirubin standard when the total bilirubin levels were 28.2 mg/dL, 22.5 mg/dL, and 18.3 mg/dL, respectively. One sample was interpolated to give a positive acetaminophen reading when diluted to a total bilirubin concentration of 15 mg/L. None of the samples tested with GC/MS or the EMIT assay resulted in any detectable acetaminophen. In conclusion, caution must be taken utilizing the GDS Diagnostic assay for the quantification of acetaminophen with concomitant hyperbilirubinemia. Alternatives such as EMIT or GC/MS should be employed to assess acetaminophen levels in such patients.     

Uncontrolled Hemorrhage in Insulin-dependent Diabetic Rats

Objectives:  Diabetes mellitus (DM) is a known risk factor for higher morbidity and mortality after trauma. The authors tested the hypothesis that there is a difference in the response to uncontrolled hemorrhage between normal euglycemic rats and insulin-dependent diabetic rats.
Methods:  Thirty-one adult male Sprague-Dawley rats were used in this study. Fifteen streptozocin (STZ)-injected rats became diabetic (DM+) 2 weeks after treatment. Sixteen rats served as nondiabetic controls (DM–). All rats were anesthetized with Althesin and their femoral arteries were catheterized via cutdown, allowing continuous monitoring of vital signs. Sixteen (eight DM–, eight DM+) rats underwent uncontrolled hemorrhage by 75% tail amputation. Fifteen (eight DM–, seven DM+) rats served as nonhemorrhage controls. The mean arterial pressure (MAP), lactate, and cumulative hemorrhage volume per 100 g were measured prehemorrhage and then every 15 minutes posthemorrhage for 2 hours. Data were reported as mean ± standard deviation. Interval data were analyzed by analysis of variance (two tails, α = 0.05).
Results:  Prehemorrhage glucose was significantly higher (p < 0.001) in the DM+ (357.9 ± 22.2 mg/dL) versus DM– (125.7 ± 9.7 mg/dL) rats. At baseline, there was no significant difference in weight, MAP, or lactate between DM+ and DM– rats. Body-weight-adjusted mean cumulative hemorrhage volume was significantly greater (p < 0.04) in diabetic rats (2.52 ± 0.15 cm³/100 g body weight) than the nondiabetic rats (1.86 ± 0.25 cm³/100 g body weight).
Conclusions:  Compared to nondiabetic rats, diabetic rats suffered a greater blood loss after the same uncontrolled vascular injury.