Plasma resuscitation improves and restores intestinal microcirculatory physiology following haemorrhagic shock.

BACKGROUND AND OBJECTIVES: Intestinal ischaemia-reperfusion injury following resuscitated haemorrhagic shock (HS) leads to endothelial and microcirculatory dysfunction and intestinal barrier breakdown. Although vascular smooth muscle machinery remains intact, microvascular vasoconstriction occurs secondary to endothelial cell dysfunction, resulting in further ischaemia and organ injury. Resuscitation with fresh frozen plasma (FFP) improves blood flow, stabilizes the endothelial glycocalyx and alleviates organ injury. We postulate these improvements correlate with decreased tissue CO2 concentrations, improved microvascular oxygenation and attenuation of intestinal microvascular endothelial dysfunction. MATERIALS AND METHODS: Male Sprague-Dawley rats were randomly assigned to groups (n = 8/group): (1) sham, (2) HS (40% mean arterial blood pressure [MAP], 60 min) + crystalloid resuscitation (CR) (shed blood saline) and (3) HS + FFP (shed blood + FFP). MAP, heart rate (HR), ileal perfusion, pO2 and pCO2 were measured at intervals until 4 h post-resuscitation (post-RES). At 4 h post-RES, the ileum was rinsed in situ with Krebs solution. Topical acetylcholine and then nitroprusside were applied for 10 min each. Serum was obtained, and after euthanasia, tissues were harvested and snap-frozen in liquid N2 and stored at -80°C. RESULTS: FFP resuscitation resulted in sustained ileal perfusion as well as rapid sustained return to baseline microvascular pO2 and pCO2 values when compared to CR (p < 0.05). Endothelial function was preserved relative to sham in the FFP group but not in the CR group (p < 0.05). CONCLUSION: FFP-based resuscitation improves intestinal perfusion immediately following resuscitation, which correlates with improved tissue oxygenation and decreased tissue CO2 levels. CR resulted in significant damage to endothelial vasodilation response to acetylcholine, while FFP preserved this function.

Management of complicated biliary disease in the pediatric population.

BACKGROUND: Cholesterol stones and biliary dyskinesia have replaced hemolytic disease as the primary indication for pediatric cholecystectomy. This study looks at the cohort of pediatric patients with complicated biliary disease, defined as choledocholithiasis and/or gallstone pancreatitis, to determine the incidence and best treatment options. METHODS: A retrospective review of all cholecystectomies performed over 15 years admitted to the surgical service at a single free-standing children's hospital was performed. Patient factors, indications for cholecystectomy, and final treatment were recorded. Complicated gallbladder disease was defined as having image-confirmed choledocholithiasis or gallstone pancreatitis. High-risk patients were those with imaging that demonstrated definitive choledocholithiasis or cholelithiasis with common bile duct enlargement. Low risk patients were those with cholelithiasis or gallbladder sludge on imaging combined with an elevated bilirubin and/or lipase. RESULTS: A total of 695 cholecystectomies were performed over the 15-year time period. Average patient age was 13.4 years. Of the 695 cholecystectomies, 457 were performed for stone disease (66%) (64 hemolytic) and 236 (34.0%) were performed for biliary dyskinesia. Hundred and three (14.8% of all cholecystectomies, 22.5% of those with stone disease) presented with choledocholithiasis and/or gallstone pancreatitis (complicated disease). In high-risk patients, 28/47 (59.6%) underwent endoscopic retrograde cholangiopancreatography/sphincterotomy. In low-risk patients (no choledocholithiasis or common duct enlargement), 13/56 (23.2%) required endoscopic retrograde cholangiopancreatography/sphincterotomy (P < .05). The indication for endoscopic retrograde cholangiopancreatography after cholecystectomy was choledocholithiasis and none of these patients had bile leak complications. CONCLUSION: The incidence of pediatric complicated biliary disease due to cholesterol stones is equal to that of adults. These data suggest that a patient with imaging evidence of choledocholithiasis or common bile duct enlargement may require endoscopic retrograde cholangiopancreatography, dependent on clinical course, and this should be strongly considered before cholecystectomy. Those without such radiographic findings can undergo laparoscopic cholecystectomy and have postoperative endoscopic retrograde cholangiopancreatography if needed.

Effect of Plasma Resuscitation with Adjunctive Peritoneal Resuscitation on Hepatic Blood Flow and End-Organ Damage after Hemorrhagic Shock.

BACKGROUND: Intestinal injury from resuscitated hemorrhagic shock (HS) disrupts intestinal microvascular flow and causes enterocyte apoptosis, intestinal barrier breakdown, and injury to multiple organs. Fresh frozen plasma (FFP) resuscitation or directed peritoneal (DPR) resuscitation protect endothelial glycocalyx, improve intestinal blood flow, and alleviate intestinal injury. We postulated that FFP plus DPR might improve effective hepatic blood flow (EHBF) and prevent associated organ injury (liver, heart). STUDY DESIGN: Anesthetized Sprague-Dawley rats underwent HS (40% mean arterial pressure, 60 minutes) and were randomly assigned to groups (n = 8 per group): Sham; crystalloid resuscitation (CR; shed blood + 2 volumes CR); DPR (intraperitoneal 2.5% peritoneal dialysis fluid); FFP (shed blood + 1 vol IV FFP); FFP + DPR. EHBF was measured at postresuscitation timepoints. Organ injury was evaluated by serum ELISA (fatty acid-binding protein [FABP]-1 [liver], FABP-3 [heart], Troponin-I [heart], and Troponin-C [heart]) and hematoxylin and eosin. Differences were evaluated by 1-way ANOVA and 2-way repeated-measures ANOVA. RESULTS: CR resuscitation alone did not sustain EHBF. FFP resuscitation restored EHBF after resuscitation (2 hours, 3 hours, and 4 hours). DPR resuscitation restored EHBF throughout the postresuscitation period but failed to restore serum FABP-1 VS other groups. Combination FFP + DPR rapidly and sustainably restored EHBF and decreased organ injury. CR and DPR alone had elevated organ injury (FABP-1 [hepatocyte], FABP-3 [cardiac], and Troponin-I/C), whereas FFP or FFP + DPR demonstrated reduced injury at 4 hours after resuscitation. CONCLUSION: HS decreased EHBF, hepatocyte injury, and cardiac injury as evidenced by serology. FFP resuscitation improved EHBF and decreased organ damage. Although DPR resuscitation resulted in sustained EHBF, this alone failed to decrease hepatocyte or cardiac injury. Combination therapy with DPR and FFP may be a novel method to improve intestinal and hepatic blood flow and decrease organ injury after HS/resuscitation.

Plasma resuscitation with adjunctive peritoneal resuscitation reduces ischemia-induced intestinal barrier breakdown following hemorrhagic shock.

INTRODUCTION: Hemorrhagic shock (HS) and resuscitation (RES) cause ischemia-induced intestinal permeability due to intestinal barrier breakdown, damage to the endothelium, and tight junction (TJ) complex disruption between enterocytes. The effect of hemostatic RES with blood products on this phenomenon is unknown. Previously, we showed that fresh frozen plasma (FFP) RES, with or without directed peritoneal resuscitation (DPR) improved blood flow and alleviated organ injury and enterocyte damage following HS/RES. We hypothesized that FFP might decrease TJ injury and attenuate ischemia-induced intestinal permeability following HS/RES. METHODS: Sprague-Dawley rats were randomly assigned to groups (n = 8): sham; crystalloid resuscitation (CR) (HS of 40% mean arterial pressure for 60 minutes) and CR (shed blood plus two volumes of CR); CR and DPR (intraperitoneal 2.5% peritoneal dialysis fluid); FFP (shed blood plus one volume of FFP); and FFP and DPR (intraperitoneal dialysis fluid plus two volumes of FFP). Fluorescein isothiocyanate-dextran (molecular weight, 4 kDa; FD4) was instilled into the gastrointestinal tract before hemorrhage; FD4 was measured by UV spectrometry at various time points. Plasma syndecan-1 and ileum tissue TJ proteins were measured using enzyme-linked immunosorbent assay. Immunofluorescence was used to visualize claudin-4 concentrations at 4 hours following HS/RES. RESULTS: Following HS, FFP attenuated FD4 leak across the intestine at all time points compared with CR and DPR alone. This response was significantly improved with the adjunctive DPR at 3 and 4 hours post-RES (p < 0.05). Resuscitation with FFP-DPR increased intestinal tissue concentrations of TJ proteins and decreased plasma syndecan-1. Immunofluorescence demonstrated decreased mobilization of claudin-4 in both FFP and FFP-DPR groups. CONCLUSION: Fresh frozen plasma-based RES improves intestinal TJ and endothelial integrity. The addition of DPR can further stabilize TJs and attenuate intestinal permeability. Combination therapy with DPR and FFP to mitigate intestinal barrier breakdown following shock could be a novel method of reducing ischemia-induced intestinal permeability and systemic inflammation after trauma. LEVEL OF EVIDENCE: Prognostic/Epidemiologic, Level III.

Radiographic Determination of Skeletal Maturity Guides Optimal Timing of Bar Removal After Minimally Invasive Repair of Pectus Excavatum.

BACKGROUND: A small number of patients treated with minimally invasive correction of pectus excavatum recur after bar removal. This risk appears to be greater in younger children who continue to grow following bar removal. METHODS: We propose the use of wrist films to determine skeletal maturity and delay bar removal until it is completed. This is not possible in very young patients (less than 14 years of age) or necessary in patients older than 19. RESULTS: In the 14-year to 18-year age group, we have used wrist films to determine skeletal maturity in 25 patients. Ten patients (age 14-18) demonstrated full maturation, and their bars were removed at 2 years. Five patients had films that demonstrated nearly closed growth plates, and those bars were removed 6 months later (2.5 years post-insertion). Ten patients had 2 sets of films taken, initially at 2 years post-operation demonstrating open growth plates. Films 12 months later showed skeletal maturation. Their bars were removed at 3 years post-operation. There were no recurrences with an average follow-up of 3 years. DISCUSSION: Radiographic determination of skeletal maturity may be used as a guide to the timing of bar removal following the correction of pectus excavatum.

Plasma resuscitation with adjunctive peritoneal resuscitation reduces ischemic intestinal injury following hemorrhagic shock.

INTRODUCTION: Impaired intestinal microvascular perfusion following resuscitated hemorrhagic shock (HS) leads to ischemia-reperfusion injury, microvascular dysfunction, and intestinal epithelial injury, which contribute to the development of multiple organ dysfunction syndrome in some trauma patients. Restoration of central hemodynamics with traditional methods alone often fails to fully restore microvascular perfusion and does not protect against ischemia-reperfusion injury. We hypothesized that resuscitation (RES) with fresh frozen plasma (FFP) alone or combined with direct peritoneal resuscitation (DPR) with 2.5% Delflex solution might improve blood flow and decrease intestinal injury compared with conventional RES or RES with DPR alone. METHODS: Sprague-Dawley rats underwent HS (40% mean arterial pressure) for 60 minutes and were randomly assigned to a RES group (n = 8): sham, HS-crystalloid resuscitation (CR) (shed blood + two volumes CR), HS-CR-DPR (intraperitoneal 2.5% peritoneal dialysis fluid), HS-FFP (shed blood + two volumes FFP), and HS-DPR-FFP (intraperitoneal dialysis fluid + two volumes FFP). Laser Doppler flowmeter evaluation of the ileum, serum samples for fatty acid binding protein enzyme-linked immunosorbent assay, and hematoxylin and eosin (H&E) staining were used to assess intestinal injury and blood flow. p Values of <0.05 were considered significant. RESULTS: Following HS, the addition of DPR to either RES modality improved intestinal blood flow. Four hours after resuscitated HS, FABP-2 (intestinal) and FABP-6 (ileal) were elevated in the CR group but reduced in the FFP and DPR groups. The H&E staining demonstrated disrupted intestinal villi in the FFP and CR groups, most significantly in the CR group. Combination therapy with FFP and DPR demonstrated negligible cellular injury in H&E graded samples and a significant reduction in fatty acid binding protein levels. CONCLUSION: Hemorrhagic shock leads to ischemic-reperfusion injury of the intestine, and both FFP and DPR alone attenuated intestinal damage; combination FFP-DPR therapy alleviated most signs of organ injury. Resuscitation with FFP-DPR to restore intestinal blood flow following shock could be an essential method of reducing morbidity and mortality after trauma.

Genome Sequences of Four Cluster P Mycobacteriophages.

Four bacteriophages infecting Mycobacterium smegmatis mc2155 (three belonging to subcluster P1 and one belonging to subcluster P2) were isolated from soil and sequenced. All four phages are similar in the left arm of their genomes, but the P2 phage differs in the right arm. All four genomes contain features of temperate phages.