Prophylactic treatment with desmopressin does not reduce postoperative bleeding after coronary surgery in patients treated with aspirin before surgery

The synthetic vasopressin analog desmopressin has hemostatic properties and may reduce postoperative bleeding after coronary artery bypass grafting (CABG). A study on the effects of recent aspirin ingestion on platelet function in cardiac surgery showed a greater impairment of platelet function in patients treated with aspirin <2 days before the operation. We evaluated the effects of desmopressin on postoperative bleeding in CABG patients who were treated with aspirin 75 or 160 mg until the day before surgery. The study was a prospective, randomized, double-blinded, placebo-controlled, parallel group trial. One-hundred patients were included and divided into two groups. One group received desmopressin 0.3 micro g/kg and the other received placebo (0.9% NaCl) after the neutralization of heparin with protamine sulfate. Postoperative blood loss was recorded for 16 h. The mean (SD) bleeding was 606 (237) mL in the desmopressin group and 601 (301) mL in the placebo group (P = 0.93), representing no significant difference (95% confidence interval, -107 to 117 mL). We conclude that desmopressin does not reduce postoperative bleeding in CABG patients treated with aspirin until the day before surgery. IMPLICATIONS: Continuation of aspirin until the day before coronary artery bypass grafting may increase postoperative bleeding. The administration of desmopressin to these patients after the neutralization of heparin with protamine sulfate does not reduce postoperative bleeding.     

Inhalation of insulin in dogs: assessment of insulin levels and comparison to subcutaneous injection

Pulmonary insulin delivery is being developed as a more acceptable alternative to conventional subcutaneous administration. In 15 healthy Beagle dogs (average weight 9.3 kg), we compared insulin distribution in arterial, deep venous, and hepatic portal circulation. Dogs received 0.36 units/kg s.c. regular human insulin (n = 6) or 1 mg (2.8 units/kg) or 2 mg (5.6 units/kg) dry-powder human inhaled insulin (n = 3 and 6, respectively). Postinhalation of inhaled insulin (1 or 2 mg), arterial insulin levels quickly rose to a maximum of 55 +/- 6 or 92 +/- 9 microU/ml, respectively, declining to typical fasting levels by 3 h. Portal levels were lower than arterial levels at both doses, while deep venous levels were intermediate to arterial and portal levels. In contrast, subcutaneous insulin was associated with a delayed and lower peak arterial concentration (55 +/- 8 microU/ml at 64 min), requiring 6 h to return to baseline. Peak portal levels for subcutaneous insulin were comparable to those for 1 mg and significantly less than those for 2 mg inhaled insulin, although portal area under the curve (AUC) was comparable for the subcutaneous and 2-mg groups. The highest insulin levels with subcutaneous administration were seen in the deep venous circulation. Interestingly, the amount of glucose required for maintaining euglycemia was highest with 2 mg inhaled insulin. We conclude that plasma insulin AUC for the arterial insulin level (muscle) and hepatic sinusoidal insulin level (liver) is comparable for 2 mg inhaled insulin and 0.36 units/kg subcutaneous insulin. In addition, arterial peak concentration following insulin inhalation is two times greater than subcutaneous injection; however, the insulin is present in the circulation for half the time.     

105Changes in Nitric Oxide Levels After Deep Dermal injury in the Female,Red Duroc Pig (FRDP)

Introduction : Hypertrophic scar is a devastating sequel to burns and other tangential skin injuries. It follows deep dermal injuries and does not occur after superficial injuries. Nitric oxide (NO) plays many important roles in wound healing from inflammation to scar remodeling. Studies have shown that expression of nitric oxide synthase and nitric oxide production are decreased in human hypertrophic scar. However little is known about NO involvement in the early stages of hypertrophic scarring, because of the lack of an animal model. It was recently reported that the female red Duroc pig (FRDP) makes thick scar, which is similar to human hypertrophic scar. We hypothesized that NO production in wounds on the female, red Duroc pig is similar to that of human hypertrophic scar and that NO involvement in deep wounds is different from that in superficial wounds. Methods : Superficial (0.015” to 0.030”) and deep (0.045” to 0.060”) wounds were created on the backs of four FRDPs. Biopsies were collected at weeks 1.5, 4, 8 and 21 post wounding including samples of uninjured skin. Nitric oxide levels were measured with the Griess reaction assay and normalized with tissue protein level. Results : Superficial wounds healed with an invisible scar whereas the deep wounds healed with scar resembling mild hypertrophic scar. The thickness of the scars from the deep wounds was significantly greater than uninjured skin and healed superficial wounds (p < 0.01). NO levels were increased at 1.5 weeks in deep wounds compared to superficial wounds and uninjured skin (p < 0.05). At 8 weeks, NO levels in deep wounds had returned to the level of uninjured tissue and superficial wounds. By 21 weeks, NO levels had decreased significantly when compared to superficial wounds (p < 0.01). There were no differences in NO levels between uninjured skin and superficial wounds at any time point (p > 0.05). Conclusions : NO production is similar in late, deep wounds on the female, red Duroc pig to that reported in the literature for human hypertrophic scar further validating this animal model. NO production is quite different after deep wounds as compared to superficial wounds in the FRDP. Early elevation in nitric oxide production might account for excessive inflammation in deep wounds that become thick scars in the FRDP. Nitric oxide regulators and effects at early stages of scar formation should be elucidated further and the FRDP appears to be a useful model.     

Spinal epidural abscess after cervical pharyngoesophageal dilation

BACKGROUND: Esophageal perforation is an uncommon but known complication of esophageal dilation. Abscess after esophageal tear is rare, especially in the spinal epidural space. This is one case report of such an abscess. METHODS: We present a case of a spinal epidural abscess after cervical pharyngoesophageal dilation. RESULTS: After surgical decompression and abscess drainage, long-term intravenous antibiotics, and physical therapy, the patient has regained some functional use of her left upper extremity. CONCLUSIONS: Early diagnosis with a gadolinium-enhanced MRI and aggressive surgical treatment are keys to successful management with a good functional outcome after this unfortunate complication.     

A triple-blinded randomized trial comparing the hemostatic effects of large-dose 10% hydroxyethyl starch 264/0.45 versus 5% albumin during major reconstructive surgery

In Canada, hydroxyethyl starch 264/0.45 (HES 264/0.45; molar weight 264 kDa, molar substitution 0.45) has largely replaced albumin as the colloidal fluid of choice for perioperative intravascular volume expansion. The maximum recommended dose of HES 264/0.45 is 28 mL/kg; however, there are no clinical data supporting this limit. In this study we compared the hemostatic effects of HES 264/0.45 versus 5% albumin in doses up to 45 mL/kg over 24 h during major reconstructive head and neck surgery. Fifty patients were randomized to receive HES 264/0.45 or 5% human albumin from the induction of anesthesia until 24 h thereafter. Both albumin and HES 264/0.45 effectively maintained physiologic variables in the perioperative and postoperative periods. The partial thromboplastin time and international normalized ratio were significantly increased in the HES 264/0.45 group compared with the albumin group after infusion of 30 mL/kg and 45 mL/kg (P < 0.05). Factor VIII activity and von Willebrand factor level were significantly reduced in the HES 264/0.45 group compared with the albumin group after infusion of 15 mL/kg, 30 mL/kg, and 45 mL/kg (P < 0.05). Significantly more subjects in the HES 264/0.45 group received allogeneic red blood cell transfusions (P < 0.02). We conclude that HES 264/0.45 infusions >30 mL/kg over 24 h impair coagulation to a greater extent than albumin, possibly leading to more allogeneic transfusions.     

Acetabular component revision using a porous tantalum biomaterial: a case series

Biologic ingrowth can be difficult to achieve in acetabular component revision, especially in cases with significant bone loss. The purpose of this study was to review our clinical results of acetabular component revisions in patients with significant bone loss using a porous tantalum biomaterial. This is a retrospective review of 25 patients. There were 16 females and 9 males with a mean age of 71.7 ± 10.54 years. The mean follow up was 39 ± 11.09 months (range, 28-55 months). All patients in this series had combined segmental and cavitary bone loss, Paprosky type 2 or type 3. Of 22 patients in this series, 21 had a well-fixed and functioning implant at latest follow up. All 21 patients developed ingrowth along the tantalum surface despite compromised host bone. There were no cases of dislocation or aseptic loosening. Porous tantalum appears to be a promising material for use in revision hip arthroplasty to facilitate biologic ingrowth in patients with acetabular bone loss.     

When is the best time to deliver behavioral intervention to bariatric surgery patients: before or after surgery?

BackgroundMany comprehensive bariatric surgery programs have implemented preoperative behavioral interventions for patients presenting with problematic eating behaviors in an effort to enhance postoperative weight loss and improve psychosocial adjustment. However, it is unknown whether these interventions are best delivered pre- or postoperatively. The purpose of this study was to determine when bariatric surgery patients are most receptive to a behavioral intervention, before or after surgery.MethodsA total of 32 pre- and postoperative patients were referred to a 10-week intervention designed to reduce eating behaviors associated with postoperative weight gain (e.g., loss of control while eating, grazing). The sample was 78.1% female and 84.4% white, with an average age of 49.43 ± 9.13 years and a body mass index of 44.22 ± 6.48 kg/m². Of the 32 patients, 21 were referred preoperatively and 11 were referred postoperatively (5.63 ± 2.91 months after surgery). These patients were tracked prospectively to determine whether pre- or postoperative patients were more likely to attend and complete the behavioral intervention.ResultsCompared with the preoperative patients, the postoperative patients were more likely to follow-up with their referral and initiate treatment [χ²(1) = 10.06, P = .002]. Of the postoperative patients, 100% attended the first intervention session compared with only 43% of preoperative patients. The postoperative patients also attended more intervention sessions [t(18) = 2.51, P = .02] and were more likely to complete the intervention [χ²(1) = 7.21, P = .007]. Only 14% of the preoperative referral patients completed the program compared with 91% of the postoperative patients.ConclusionComprehensive bariatric surgery programs ought to consider balancing the needs of the preoperative patients presenting with maladaptive eating behavior with the likelihood of them participating in a behavioral intervention before surgery.