Dosage selection and effect evaluation of sodium pentobarbital in tree shrew anesthesia.

To achieve surgical anesthesia in animal experimentation, it is important to select the appropriate anesthetic dose. However, few studies have investigated the reasonable anesthetic dose in tree shrew (Tupaia belangeri). The aim of the study was to review the literature to determine the most commonly used anesthetic dose in tree shrew and to calculate the reasonable equivalent dose between tree shrew and rat based on the body surface area conversion. Two groups of 10 adult tree shrews each were anesthetized with 1% sodium pentobarbital through intraperitoneal injection separately at doses of 62 mg/kg (equivalent dose) and 40 mg/kg (reported dose). Anesthetic depth and times were assessed in addition to vital signs. The results showed that the dosage was quite different across studies, ranging from 15 mg/kg to 80 mg/kg, with 40 mg/kg being the most frequently reported dose. However, the group of tree shrews anesthetized with the commonly reported dose were unable to meet the requirements of surgery. In contrast, the equivalent dose (62 mg/kg, intraperitoneal injection with sodium pentobarbital) calculated by body surface area conversion could achieve an anesthetic time of 44.28 ± 3.95 min with no serious or fatal effects. During anesthetic monitoring, we found that sodium pentobarbital had an inhibitory effect on the blood pressure, pulse rate, respiratory rate and rectal temperature in tree shrews, especially on the respiratory rate. Thus, our study indicated that the use of the equivalent dose of sodium pentobarbital was effective in anesthetizing tree shrews.

Body surface area-based equivalent dose calculation in tree shrew.

Tree shrew (Tupaia belangeri) is a promising experimental animal in biomedical research, but the equivalent doses of drugs between tree shrew and human and other animals has not been explored, which hinders its further application in a wider scope. The main objective of this article is to provide a method of equivalent dose conversion between tree shrews and other species based on body surface area (BSA). BSA of tree shrews were measured by Image J software, and then the average Km value of tree shrews was figured out based on the body weights and BSA, then the conversion coefficients of equivalent dose among tree shrew and other species of experimental animals were calculated based known data. The Km value of tree shrews was 0.105 ± 0.001. Through BSA conversion, the equivalent dose for tree shrews (D-ts) relative to rats was obtained by formula: D-ts = 1.36 × D-a (rats weighing 200g as example), and the error was less than 10% when the BW of the tree shrew was 0.09 kg-0.15 kg. The coefficients of equivalent dose transferring from tree shrews to human and other species were calculated in article. These parameters could be used to determine a suitable dosing strategy for tree shrew studies.

Plasma volume, cell volume, total blood volume and F factor in the tree shrew.

In this study, the physiological values of volumes of plasma, cells, total blood and the F blood factors were identified in 24 adult tree shrews (Tupaia belangeri; 12 male and 12 female; average BW of 123.9±19.19 g). The two-compartment model method of Evans Blue dye was used to obtain the plasma volume and the venous hematocrit was measured by microhematocrit method. To establish the relationship between body weight (BW) and blood volume of tree shrews, We performed linear fitting for these two datasets. Results were analyzed according to gender and weight (<120g vs.>120g). Statistical significance was assessed using the unpaired student t test and one-way ANOVA. The average volumes per 100g body weight of plasma, red blood cell (RBC) and total blood were 5.42±0.543, 3.24±0.445, and 8.66±0.680ml respectively. The mean body hematocrit, cardiac hematocrit, jugular vein hematocrit, femoral vein hematocrit, and tail vein hematocrit was 37.43±4.096, 39.72±3.219, 43.04±4.717, 40.84±3.041, and 38.71±3.442% respectively. The F cardiac was 0.94±0.072, F jugular vein 0.88±0.118, F femoral vein 0.92±0.111, and the F tail vein 0.97±0.117. Blood volume (ml) was 85.89103×BW (kg). This is the first study to provide the parameters of plasma volume, cell volume, total blood volume and F factor and a baseline for future research on blood physiology of tree shrews.

[Risk factors affecting the survival rate in serious multiple trauma patients associated with acute lung injure/acute respiratory distress syndrome].

OBJECTIVE: To investigate risk factors affecting the survival rate in serious multiple traumatic patients associated with acute lung injure (ALI)/acute respiratory distress syndrome (ARDS). METHODS: The clinical data of 76 serious multiple trauma patients associated with ALI and 95 cases in ARDS, totally 171 patients associated with ALI/ARDS, were retrospectively studied, and stepwise logistic regression analysis was used to analyze 20 possible risk factors affecting survival rate. RESULTS: The risk factors affecting survival rate in the ALI group: included smoking (B = -5.235, OR = 0.005, P = 0.001), sepsis secondary to trauma (B = -2.753, OR = 0.064, P = 0.031), and gastrointestinal hemorrhage (B = -2.876, OR = 0.056, P = 0.033). The risk factors affecting survival rate in the ARDS group included the time of induction factor persisting to attacking (B = 3.524, OR = 33.933, P = 0.008), sepsis secondary to trauma (B = -5.183, OR = 0.006, P = 0.004); renal insufficiency(B = -4.745, OR = 0.009, P = 0.009), and gastrointestinal hemorrhage (B = -6.335, OR = 0.002, P = 0.007). CONCLUSION: Different from the results of study of traditional risk factors affecting survival rate in ALI/ARDS, this study reveals that smoking may be an independent risk factor; the earlier ALI/ARDS appears, the lower the predictable survival rate in condition of serious multiple trauma; MODS is easily induced in the course of complicating renal insufficiency during the time of lung injury; sepsis and gastrointestinal hemorrhage are still the infective factors or infection inducing factors affecting the survival rate after trauma; and the primary disease causing infection must be treated actively.

An anatomical study of corona mortis and its clinical significance.

OBJECTIVE: To provide detailed information of corona mortis for ilioinguinal approach as an anterior approach to the acetabulum and pelvis. METHODS: The course, branches and distribution of the vascular connection between the obturator system and the external iliac or inferior epigastric systems located over the superior pubic ramus were observed on 50 hemipelvises with intact soft tissues. RESULTS: During the dissections, 72% of the cadaveric sides had at least one communicating vessel between the obturator system and the external iliac or inferior epigastric systems on the superior pubic ramus. The average diameter of the connecting vessel was 2.6 mm (range, 2.0-4.2 mm). It coursed over the superior pubic ramus or iliopubic eminence vertically to enter the obturator foramen and exit the pelvis. The average distance from pubic symphysis to the vascular connections between the obturator and external iliac systems was 52 mm (range, 38-68 mm). CONCLUSIONS: Vascular connections between the obturator system and the external iliac or inferior epigastric systems were found over the superior pubic ramus with a high incidence. They are prone to damage during the ilioinguinal approach as an anterior approach to the acetabulum and pelvis. Thus, corona mortis located over the superior pubic ramus deserves great attention during the ilioinguinal approach.

[Expression and significance of substance P, neurofilament-H in glomus tumors with chronic pain].

OBJECTIVE: To observe the expression and distribution of substance P (SP), neurofilament-H (NFH) in glomus tumors with chronic pain, and to discuss the process of chronic pain and the relationship with pain degree. METHODS: Twenty-seven patients diagnosed as glomus tumor with chronic pain were enrolled as case group, and divided into light pain symptomatic group (LPSG) (n = 12) and severe pain symptomatic group (SPSG) (n = 15) according to clinical manifestations. Control group (CG) were enrolled by 30 patients with amputated extremities or hands after trauma. Immunohistochemical methods were used to determine the expression of SP, NFH which were detected quantitatively by computer graph analysis system too. RESULTS: The positive expression and distribution of SP, NFH existed in all the three groups and SPSG expression level was the highest [Grayscale Value(SP) (143.3 +/- 7.5), Grayscale Value(NFH) (167.7 +/- 4.4)], LPSG followed [Grayscale Value(SP) (156.2 +/- 8.2), Grayscale Value(NFH) (194.8 +/- 4.0)], control group was the third [Grayscale Value(SP) (208.2 +/- 16.6), Grayscale Value(NFH) (225.1 +/- 8.3)]; The difference of expression level among three groups was significant [SPSG vs LPSG (P(SP) = 0.002, P(NFH) < 0.0001), SPSG vs CG (P(SP) < 0.0001, P(NFH) < 0.0001), LPSG vs CG (P(SP) < 0.0001, P(NFH) < 0.0001)]. The findings of Pearson product-moment correlation analysis between quantitative grayscale value of SP, NFH respectively and pain score in all the patients with glomus tumor showed linear negative correlation (r(SP) = -0.8974, P(SP) = 0.000001; r(NFH) = -0.6545, P(NFH) = 0.000212). CONCLUSION: SP is the mainly afferent pain transmitter in the process of chronic pain in glomus tumor, and NFH plays an important role in pain-transmitted activities.