Peritoneal Resuscitation Research Articles

Adjunctive treatment of abdominal catastrophes and sepsis with direct peritoneal resuscitation: indications for use in acute care surgery.

The success of damage-control surgery (DCS) for the treatment of trauma has led to its use in other surgical problems such as abdominal sepsis. Previous studies using direct peritoneal resuscitation (DPR) for the treatment of trauma have yielded promising results. We present the results of the application of this technique to patients experiencing abdominal sepsis. We enrolled 88 DCS patients during a 5 year-period (January 2008 to December 2012) into a propensity-matched study to evaluate the utility of using DPR in addition to standard resuscitation. DPR consisted of peritoneal lavage with 2.5% DELFLEX, and abdominal closure was standardized across both groups. Patients were matched using Acute Physiology and Chronic Health Evaluation II (APACHE II) variables. Univariate and multivariate analyses were performed. There were no differences between the control and experimental groups with regard to age, sex, ethnicity, or APACHE II at 24 hours. Indications for damage control included pancreatitis, perforated hollow viscous, bowel obstruction, and ischemic enterocolitis. Patients undergoing DPR had both a higher rate of (68% vs. 43%, p < 0.03) and a shorter time to definitive fascial closure (5.9 [3.2] days vs. 7.7 [4.1] days, p < 0.02). DPR patients had a decreased APACHE II and Sequential Organ Failure Assessment (SOFA) score compared with the controls at 48 hours. In addition, DPR patients had fewer abdominal complications compared with the controls (RR, 0.57; 95% confidence interval, 0.32-1.01; p = 0.038). Ventilator days and intensive care unit length of stay were both significantly reduced in the DPR group. The DPR group showed a lower overall mortality at 30 days (16% vs. 27%, p = 0.15). DPR reduces time to definitive abdominal closure, increases primary fascial closure, and reduces intra-abdominal complications following DCS. DPR may also attenuate progressive physiologic injury as demonstrated by a reduction in 48-hour intensive care unit severity scores. As a result, DPR following DCS may afford better outcomes to patients experiencing shock. Therapeutic study, level III.

Effects of pyruvate-enriched peritoneal dialysis solution on intestinal barrier in peritoneal resuscitation from hemorrhagic shock in rats

BackgroundTo investigate protective effects of pyruvate-enriched peritoneal dialysis solution (P-PDS), compared with lactate-PDS (L-PDS), on the intestinal mucosal barrier in peritoneal resuscitation (PR) from severe hemorrhagic shock (HS) in rats. Materials and methodsFifty male SD rats were randomly divided into five groups (n = 10): group sham, group control (HS without fluid resuscitation), group intravenous resuscitation (IVR) (HS with IVR only), group L-PDS (HS with IV infusion plus PR with L-PDS), and group P-PDS (HS with IV infusion plus PR with P-PDS). HS was induced by hemorrhage with mean arterial pressure 40 mm Hg for 60 min. In three groups with fluid rehydration, IVR included shed blood and dl-lactate Ringer solution equal to two times the volume of shed blood during 60 min; in two groups with PR, 20 mL of L-PDS, or P-PDS were infused when IV infusion started after HS into the peritoneal cavity in 20 min, respectively. Blood samples were taken for determinations of pH, base excess, PaCO2, PaO2, and D-LA 60 min post fluid resuscitation. After rats were sacrificed, a segment of intestine was harvested for the detection of expressions of intestinal barrier proteins: zonula occludens-1 (ZO-1) and phosphorylated vasodilator-stimulated phosphoprotein (p-VASP) by Western blot and immunohistochemistry. Intestinal morphologic alterations were also observed. ResultsBlood pH, base excess, and PaO2 were higher, whereas PaCO2 and D-LA were lower in group P-PDS than in other three HS groups (P < 0.05 and P < 0.01, respectively). Severe acidosis was nearly corrected in group P-PDS. Intestinal barrier proteins ZO-1 and p-VASP were significantly preserved in group P-PDS than in group L-PDS (P < 0.05) although they were improved in group L-PDS in comparison with other two HS groups (P < 0.05 or P < 0.01). Expressions of barrier proteins by Western blotting in group P-PDS were reversed to normal. The score of intestinal epithelial damage index was reduced in group L-PDS, compared with other two HS groups (P < 0.05), however, it was significantly lower in group P-PDS than in group L-PDS (P < 0.05). ConclusionsPyruvate was superior to lactate in PDS in the correction of severe acidosis with PR. P-PDS was more preservative of expressions of intestinal ZO-1 and p-VASP and mucosal barrier function, compared with L-PDS in PR from severe HS in rats.

Pyruvate Is Superior to Reverse Visceral Hypoperfusion in Peritoneal Resuscitation From Hemorrhagic Shock in Rats

The objective of this study was to investigate the effects of pyruvate-containing fluids on peritoneal resuscitation (PR), following intravenous fluid resuscitation from hemorrhagic shock (HS) in rats. One hundred rats following 1-h HS with mean arterial pressure 35 ± 5 mmHg were randomly assigned to five groups (n = 10) in each of two comparable sets: group VR: intravenous resuscitation (VR) only and four groups with PR after VR: groups NS, LA, P1, and P2, resuscitated with normal saline, lactated peritoneal dialysis solution (PDS), pyruvated PDS, and 2.2% pyruvate, respectively. The splanchnic blood flow on surfaces of liver, kidney, and intestinal mucosa was detected. Blood samples were taken before HS and at T180 or T360 in these two animal sets after hemorrhage for function tests of liver, kidney, and intestinal mucosa, respectively. The intestinal mucosal barrier protein: zonula occludens 1 (ZO-1) and tissue water contents of these organs were also determined. Splanchnic blood flow was significantly preserved in all PR groups with hyperosmolar solutions: group P1 and group P2 with pyruvate were more advantageous than group LA. Group P2 was the most efficient among groups in reverse of visceral hypoperfusion. Organ function and tissue water contents of liver, kidney, and intestine and the intestinal barrier ZO-1 density were also improved in group P1 and group P2, compared with group LA. Among organs, the pyruvate protection of intestinal mucosa was the most apparent by reversing splanchnic blood flow and diamine oxidase close to reference ranges with the highest ZO-1 density. Group P2 showed the most pyruvate protection in all test parameters among four groups with PR. Peritoneal resuscitation with hyperosmolar fluids attenuated visceral vasoconstriction and splanchnic hypoperfusion and improved the intestinal barrier protein and organ function following conventional fluid resuscitation from severe HS in rats. Pyruvate was superior to lactate in PDS as PR fluids, and 2.2% pyruvate was the optimal fluid in PR.

Effects of direct peritoneal resuscitation with sodium pyruvate from hemorrhagic shock on intestinal injury in rats

Objective To investigate the effects of direct peritoneal resuscitation (DPR) with sodium pyruvate from hemorrhagic shock (HS) on intestinal injury in rats.Methods Fifty SPF male Sprague-Dawley rats,weighing 200-250 g,were used in this study.The animals were anesthetized with 1％ pentobarbital sodium 40 mg/kg,tracheostomized and mechanically ventilated.Femoral artery was cannulated for mean arterial pressure (MAP) monitoring,blood-letting,blood sampling and fluid infusion.HS was induced according to the method described by Wiggers.MAP was maintained at 35-40 mm Hg for 60 min.The animals were then randomly and equally divided into 5 groups:sham operation group (group S) ; conventional resuscitation group (group CR) ; DPR with different fluid groups (DPRt-3 groups).In group CR,at 1 h after HS,the animals were resuscitated with infusion of the blood withdrawn and normal saline (the volume was 2 times volume of blood loss).In DPR1-3 groups,conventional resuscitation was performed,at the same time,1.5 ％ glucose-based peritoneal dialysis solution containing lactate,1.5％ glucose-based peritoneal dialysis solution containing lactate (40.00 mmol/L),and 1.5％ glucosebased peritoneal dialysis solution containing high lactate (80.00 mmol/L) 20 ml were infused intraperitoneally over 30 min,respectively.MAP was recorded before blood letting,at 5,30 and 60 min of HS,and at 5,30,60,90 and 120 min after the end of resuscitation.At 120 min after the end of resuscitation,the lactate level in the arterial blood was measured.The animals were then sacrificed.Small intestinal samples were obtained for determination of malondialdehyde (MDA) content,myeloperoxidase (MPO) activity and tumor necrosis factor-α (TNF-α) expression,and for microscopic examination.The damage to the small intestinal mucosa was assessed and scored.Results Compared with MAP before blood letting,MAP during HS was significantly decreased,and no significant change in MAP was found after resuscitation in CR and DPR1-3 groups (P ＜ 0.05).The lactate level in the arterial blood,MDA content,MPO activity,TNF-α expression and intestinal mucosal damage scores were significantly higher in CR and DPR1-3 groups than in S group (P ＜ 0.05 or 0.01),while lower in DPR1-3 groups than in CR group (P ＜0.01),and in DPR2,3 groups than in DPR1 group (P ＜ 0.05 or 0.01).The lactate level in the arterial blood,MDA content and TNF-α expression were significantly lower in DPR3 group than in DPR2 group (P ＜ 0.05 or 0.01).Conclusion Direct peritoneal resuscitation with sodium pyruvate can reduce the intestinal injury induced by HS and inhibition of lipid peroxidation and inflammatory responses is involved in the mechanism in rats. Key words: Pyruvic acid; Peritoneal dialysis; Resuscitation; Shock, hemorrhagic; Intestines; Reperfusion injury

Direct Peritoneal Resuscitation Prevents Cytoplasmic HMGB1 after Hemorrhagic Shock

Hemorrhagic shock (HS) in trauma patients results in liver injury from impaired blood flow and increased mediators of the systemic inflammatory response. These mediators include high-mobility group protein B1 (HMGB1), a marker of hepatocyte necrosis, and toll-like receptor (TLR)-4 and TLR-9, which are thought to initiate early and late inflammation in the liver during resuscitated HS. A new treatment strategy, direct peritoneal resuscitation (DPR), improved liver blood flow, function, and survival after HS.

102

Introduction: Adjunctive direct peritoneal resuscitation (DPR) with hypertonic peritoneal dialysis solution in addition to conventional resuscitation from hemorrhagic shock (HS) mitigates visceral organ injury via improved visceral blood flow (VBF) but the effect on remote organs has not been evaluated. Hypothesis: We hypothesized that DPR would decrease acute lung injury (ALI) after hemorrhagic shock. Methods: Anesthetized rats were bled to 40% MAP for 60 min to induce HS and were randomly assigned to resuscitation with shed blood + NS (CR, n=8), or CR + 30 ml of IP 2.5% Delflex (DPR, n=8). Protein expression was measured using multiplex array and individual ELISA, mRNA expression via PcR and organ injury graded in blinded manner. One way ANOVA with Tukey-Kramer was performed at a significance at p<0.01. Results: Enhanced VBF was seen in the DPR group (not shown). Lung sections from DPR animals had less edema and enhanced structural integrity. Wet to dry weight ratios for the DPR group were decreased compared to CR. (Sham 4.92 ± 0.08; CR 5.37+0.12; DPR 4.91 ± 0.07, p<0.01) Cytosolic migration of HMGB-1 (a nuclear regulatory protein) confirmed the breakdown of nuclear/cellular integrity in CR animals. Nuclear sequestration of HMGB-1 was preserved in the DPR and sham. Serum HMGB-1 levels were increased in CR compared to DPR indicating cellular necrosis with cytosolic release. (1.2 ± 0.2 vs. 6.88 ± 0.9 ng/ml, DPR vs. CR, p<0.01) Th1 serum cytokine levels were reduced in DPR animals when compared to CR. (IL1a: 10.7 ± 0.7 vs. 26.7 ± 2.7 mg/ml; INFg: 1148+23 vs. 1213 ± 88 ng/ml, DPR vs. CR; p<0.01) CR increased lung IL18 and IL12p70 protein (IL18: 5255 ± 535 vs. 6948 ± 545 ng/g; IL12p70: 19.6 ± 0.5 vs. 21.3 ± 0.7 ng/g; DPR vs. CR p<0.01) and increased mRNA expression of IL18 (+1.2 DPR/sham vs. +3.8 CR/sham, P<0.01) indicating activation and expression of these proteins in lung tissue. This correlated with increase serum level in CR compared to DPR. (IL18: 117 ± 17 vs. 213 ± 15 ng/ml; IL-12p70: 14.4 ± 0.9 vs. 13.1 ± 0.5; DPR vs. CR, p<0.01) Conclusions: DPR reduces pulmonary edema and maintains lung cellular and nuclear architecture after HS. DPR decreases shock-induced ALI possibly due to attenuating the Th1 inflammatory response.

Preservation of hepatic blood flow by direct peritoneal resuscitation improves survival and prevents hepatic inflammation following hemorrhagic shock

Conventional resuscitation (CR) from hemorrhagic shock (HS) results in gut and liver hypoperfusion, organ and cellular edema, and vital organ injury. Adjunct direct peritoneal resuscitation (DPR) with dialysate prevents gut vasoconstriction, hypoperfusion, and injury. We hypothesized that DPR might also improve hepatocellular edema, inflammation, and injury. Anesthetized male SD rats were assigned to groups (n = 8/group): 1) sham (no HS); 2) HS (40% MAP/60 min) + intravenous fluid conventional resuscitation [CR; shed blood + 2 vol saline (SAL)/30 min]; 3) HS+CR+DPR (30 ml ip 2.5% glucose dialysate); or 4) HS+CR+SAL (30 ml ip saline). Histopathology showed lung and liver injury in HS+CR and HS+CR+SAL up to 24-h postresuscitation (post-RES) that was not in shams and which was prevented by adjunct DPR. Wet-to-dry weight ratios in HS+CR revealed organ edema formation that was prevented by adjunct DPR. HS+CR and HS+CR+SAL had 34% mortality by 24-h post-RES, which was absent with DPR (0%). Liver IFN-γ and IL-6 levels were elevated in CR compared with DPR or shams. TNF-α mRNA was upregulated in CR/sham and DPR/sham. IL-17 was downregulated in DPR/sham. CXCL10 mRNA was upregulated in CR/sham but downregulated in DPR/sham. Despite restored central hemodynamic performance after CR of HS, liver blood flow was compromised up to 24 h post-RES, and the addition of DPR restores and maintains liver perfusion at 24-h post-RES. DPR prevented liver injury, histological damage, and edema formation compared with CR alone. DPR provided a mitigating anti-inflammatory dampening of the systemic inflammatory response. In all, these effects likely account for improved survivorship in the DPR-treated group.

Intestinal Microcirculatory Flow Alterations in Necrotizing Enterocolitis are Improved by Direct Peritoneal Resuscitation

Vasoconstriction of the neonatal intestinal microvasculature is a central mechanistic event in development of necrotizing enterocolitis. We hypothesized that topical treatment of the intestine with dialysate fluid would ameliorate the vasoconstriction in necrotizing enterocolitis (NEC). NEC was induced in experimental groups. Control animals were delivered vaginally and dam-fed (control group). Neonatal pups underwent laser Doppler flow study of the terminal ileum to determine real-time blood flow in the intestinal microvasculature. After baseline flow was determined, dialysis solution was added to the peritoneal cavity and alterations in microcirculation were recorded. Baseline ileal blood flow in the control group was significantly higher than in NEC rat pups at 48 hours post delivery (P < 0.05), but not at 24 hours (P = NS). Ileal blood flow increased in all groups after adding dialysate (P < 0.05), improving ileal blood flow in the 48-hour NEC group and reaching the baseline level of the 48-hour control group (P < 0.05). Our data shows blood flow to be higher in 48-hour controls as compared with 24-hour controls suggesting a time-dependency in the development of intestinal vasoregulatory processes. All groups had an increase in blood flow with dialysate treatment. This may represent a novel initial therapy to improve intestinal ischemia in human necrotizing enterocolitis.

Direct peritoneal resuscitation augments ileal blood flow in necrotizing enterocolitis via a novel mechanism

PurposeEndothelin-1, prostaglandins (PGs), and nitric oxide (NO) have been implicated in the intestinal microvascular dysfunction of necrotizing enterocolitis (NEC). We hypothesized that direct peritoneal resuscitation (DPR) dilates the intestinal microvasculature and improves blood flow independent of these mechanisms. MethodsRat pups were assigned by litter to experimental NEC or CONTROL groups. Laser Doppler flowmetry evaluation of intestinal microvascular blood flow was studied at baseline, with mediator blockade (endothelin-A receptor, endothelin-B receptor, PG synthesis, or NO synthase) and with DPR. Repeated-measures analysis of variance test was applied with Tukey-Kramer honestly significant difference test (P < .05). ResultsAt baseline, NEC animals demonstrated significantly decreased ileal blood flow as compared with CONTROLs (P < .05). Endothelin-A receptor and PG inhibition increased flow in the intestinal microvasculature, but this was significantly augmented by the addition of DPR (P < .05). Blockade of NO synthase decreased intestinal blood flow, which was overcome with addition of DPR (P < .05). ConclusionIleal blood flow was significantly reduced in NEC animals as compared with CONTROLs. The addition of DPR to the peritoneum increased ileal blood flow significantly in all groups in spite of blockade of these known vasoactive mechanisms. Direct peritoneal resuscitation may be a novel strategy to improve intestinal blood flow in NEC.

Direct Peritoneal Resuscitation Improves Obesity-Induced Hepatic Dysfunction after Trauma

The metabolic syndrome and associated fatty liver disease are thought to contribute to poor outcomes in trauma patients. Experimentally, obesity compromises liver blood flow. We sought to correlate the effect of obesity, injury severity, and liver dysfunction with trauma outcomes. We hypothesized that obesity-related liver dysfunction could be mitigated with the novel technique of adjunctive direct peritoneal resuscitation (DPR). This study has clinical and experimental arms. The clinical study was a case-controlled retrospective analysis of ICU trauma patients (n = 72 obese, n = 187 nonobese). The experimental study was a hemorrhagic shock model in obese rats to assess the effect of DPR on liver blood flow, liver function, and inflammatory mediators. In trauma patients, univariate and multivariate analyses demonstrated increasing mortality (p < 0.05), septic complications (p < 0.05), liver dysfunction (p < 0.001), and renal impairment (p < 0.05) with increasing body mass index and injury severity score. Obesity in rats impairs liver blood flow, liver function, renal function, and inflammation (interleukin [IL]-1β, IL-6, high mobility group protein B1[HMGB-1]). The addition of DPR to shock resuscitation restores liver blood flow, improves organ function, and reverses the systemic proinflammatory response. Our clinical review substantiates that obesity worsens trauma outcomes regardless of injury severity. Obesity-related liver and renal dysfunction is aggravated by injury severity. In an obese rat model of resuscitated hemorrhagic shock, the addition of DPR abrogates trauma-induced liver, renal, and inflammatory responses. We conclude that the addition of DPR to the clinical resuscitation regimen will benefit the obese trauma patient.

Preliminary resuscitation for perforated necrotizing enterocolitis: 2 cases treated with initial direct peritoneal resuscitation

We used peritoneal infusions of 2.5% dextrose solution as an adjunct to resuscitation of 2 very low-birth-weight infants having perforated necrotizing enterocolitis. This was repeated every 12 hours for 7 days before and 1 day after extensive bowel resection. The designation of this research method has been termed direct peritoneal resuscitation. We discuss our observations and the evolution of this technique from studies in the animal laboratory to a recent trial in patients with abdominal trauma. We propose that the early response benefit of this preoperative resuscitation seen in our 2 cases be investigated by others. Prospective controlled trials could then be considered for those high-risk patients having diffuse disease and shock.

Retracted] The Beneficial Effect of Direct Peritoneal Resuscitation on Septic Shock in Rats

The high mortality associated with conventionally resuscitated septic shock and the subsequent multiple-organ failure remain a very significant and costly clinical problem. Conventional simple intravenous resuscitation (CR) from septic shock often fails to restore the progressive splanchnic vasoconstriction and hypoperfusion, and fails to reverse gut-derived systemic inflammatory response and fluid sequestration. Numerous interventions have been used to protect organ systems and cellular viability from the lethal injury accompanying hypoperfusion and ischemia but none of these efforts have been sufficient to halt or reverse the main course of the pathophysiology noted with conventional resuscitated shock. Recently, some studies have found that in hemorrhagic shock, direct peritoneal resuscitation (DPR) not only produces sustained hyperperfusion in viscera but also has immunomodulatory and anti-fluid sequestration effects. Although the etiology and pathogenesis of septic shock and hemorrhagic shock differ, both kinds of shock result in hypoperfusion of the intestines and other internal organs. In this paper, we seek to determine whether DPR has a similar therapeutic effect on septic shock/resuscitation.

Direct Peritoneal Resuscitation Accelerates Primary Abdominal Wall Closure after Damage Control Surgery

Damage control surgery is a staged approach to the trauma patient in extremis that improves survival, but leads to open abdominal wounds that are difficult to manage. We evaluated whether directed peritoneal resuscitation (DPR) when used as a resuscitation strategy in severely injured trauma patients with hemorrhagic shock requiring damage control surgery would affect the amount of and timing of resuscitation and/or show benefits in time to abdominal closure and reduction of intra-abdominal complications. A retrospective case-matched study of patients undergoing damage control surgery for hemorrhagic shock secondary to trauma between January 2005 and December 2008 was performed. Twenty patients undergoing standardized wound closure and adjunctive DPR were identified and matched to 40 controls by Injury Severity Score, age, gender, and mechanism of injury. A single early death was excluded because of inability to control ongoing hemorrhage. There were no differences in age, gender, or mechanism of injury between the groups. Injury Severity Score (35.07 +/- 17.1 versus DPR 34.95 +/- 16.95; p = 0.82) and packed red blood cell administration in 24 hours (23.8 +/- 14.35 U versus DPR 26.9 +/- 14.1 U; p = 0.43) were similar between the groups. Presenting pH was similar between the study group and the DPR group (7.24 +/- 0.13 d versus DPR 7.26 +/- 0.11; p = 0.8). Time to definitive abdominal closure was significantly less in the DPR group compared with controls (DPR: 4.35 +/- 1.6 d versus 7.05 +/- 3.31; p < 0.003). DPR also allowed for a higher rate of primary fascial closure, lower intra-abdominal complication rate, and lower rate of ventral hernia formation at 6 months. Adjunctive DPR afforded a definitive wound closure advantage compared with Wittmann patch closure techniques (DPR 4.35 +/- 1.6 versus Wittmann patch 6.375 +/- 1.3; p = 0.004). The addition of adjunctive DPR to the damage control strategy shortens the interval to definitive fascial closure without affecting overall resuscitation volumes. As a result, this mitigates intra-abdominal complications associated with open abdomen and damage control surgery and affords better patient outcomes.

Modulation of Mesenteric Lymph Flow and Composition by Direct Peritoneal Resuscitation From Hemorrhagic Shock

Traditional clinical resuscitation from hemorrhagic shock that focuses on restoring central hemodynamic function does not adequately perfuse the gut. Intestinal hypoperfusion could stimulate ongoing organ failure and gut-derived systemic inflammatory response syndrome. Direct peritoneal resuscitation (DPR) that uses dialysis fluid improves perfusion and survival. We examined mesenteric lymph flow and proinflammatory constituents to determine whether DPR-stabilized interstitial compartment function could explain improved outcomes. A paired-control experimental animal study. Mesenteric lymph fluid was continuously collected in 4 groups of rats (n = 7 per group): sham group; hemorrhagic shock (50% mean arterial pressure for 30 minutes) and resuscitation (shed blood plus 2 volumes of isotonic sodium chloride for 30 minutes) group; hemorrhagic shock and resuscitation plus intraperitoneal saline (30 mL) group; and hemorrhagic shock and resuscitation plus DPR (30 mL of 2.5% clinical peritoneal dialysis fluid). Both DPR and saline were placed intraperitoneally at the time of resuscitation. Lymph composition was analyzed by enzyme-linked immunosorbent assay (ELISA) for hyaluronic acid, its ligand CD44, and cytokines. Hemorrhagic shock and resuscitation elevated lymph flow (peak mean [SEM], 20.6 [5.6] microL/min at 60 minutes after resuscitation) and CD44 serum levels (peak mean [SEM], 140.0 [12.9] ng/mL at 120 minutes after resuscitation) compared with the sham group (mean [SEM], 1.2 [0.7] microL/min and 15.6 [1.5] ng/mL), and DPR returned levels to baseline (mean [SEM], 4.4 [0.5] microL/min and 15.4 [0.3] ng/mL). Hyaluronic acid levels were elevated in the hemorrhagic shock and resuscitation group (mean [SEM], 90.0 [1.3] ng/mL) and the hemorrhagic shock and resuscitation plus intraperitoneal saline group (mean [SEM], 93.0 [1.3] ng/mL) compared with the sham group (mean [SEM], 73.7 [1.4] ng/mL) or DPR group (81.2 [0.9] ng/mL). Interferon gamma, interleukin 1beta, interleukin 6, and interleukin 10 levels were also modulated by DPR. Hemorrhagic shock and resuscitation increased lymph flow by altering capillary water transport and expanding interstitial volume. Increased lymph hyaluronic acid and inflammatory cytokines with traditional resuscitation were modulated to sham levels by DPR. In addition, DPR reduces these patterns presumably via an osmotic effect on capillary water transport. Adjunctive DPR might offer novel protection from systemic inflammatory response syndrome after hemorrhagic shock and resuscitation.

Hemorrhage-Induced Hepatic Injury and Hypoperfusion can be Prevented by Direct Peritoneal Resuscitation

BackgroundCrystalloid fluid resuscitation after hemorrhagic shock (HS) that restores/maintains central hemodynamics often culminates in multi-system organ failure and death due to persistent/progressive splanchnic hypoperfusion and end-organ damage. Adjunctive direct peritoneal resuscitation (DPR) using peritoneal dialysis solution reverses HS-induced splanchnic hypoperfusion and improves survival. We examined HS-mediated hepatic perfusion (galactose clearance), tissue injury (histopathology), and dysfunction (liver enzymes). MethodsAnesthetized rats were randomly assigned (n = 8/group): (1) sham (no HS); (2) HS (40% mean arterial pressure for 60 min) plus conventional i.v. fluid resuscitation (CR; shed blood + 2 volumes saline); (3) HS + CR + 30 mL intraperitoneal (IP) DPR; or (4) HS + CR + 30 mL IP saline. Hemodynamics and hepatic blood flow were measured for 2 h after CR completion. In duplicate animals, liver and splanchnic tissues were harvested for histopathology (blinded, graded), hepatocellular function (liver enzymes), and tissue edema (wet–dry ratio). ResultsGroup 2 decreased liver blood flow, caused liver injuries (focal to submassive necrosis, zones 2 and 3) and tissue edema, and elevated liver enzymes (alanine aminotransferase (ALT), 149 ± 28 μg/mL and aspartate aminotransferase (AST), 234 ± 24 μg/mL; p < 0.05) compared to group 1 (73 ± 9 and 119 ± 10 μg/mL, respectively). Minimal/no injuries were observed in group 3; enzymes were normalized (ALT 89 ± 9 μg/mL and AST 150 ± 17 μg/mL), and tissue edema was similar to sham. ConclusionsCR from HS restored and maintained central hemodynamics but did not restore or maintain liver perfusion and was associated with significant hepatocellular injury and dysfunction. DPR added to conventional resuscitation (blood and crystalloid) restored and maintained liver perfusion, prevented hepatocellular injury and edema, and preserved liver function.

Hemorrhagic Shock and Resuscitation-Mediated Tissue Water Distribution is Normalized by Adjunctive Peritoneal Resuscitation

Adjunctive direct peritoneal resuscitation (DPR) from hemorrhagic shock (HS) improves intestinal blood flow and abrogates postresuscitation edema. HS causes water shifts as a result of sodium redistribution and changes in transcapillary Starling forces. Conventional resuscitation (CR) with crystalloid aggravates water sequestration. We examined the compartment pattern of organ tissue water after HS and CR, and modulation of tissue edema by adjunctive DPR. Rats were hemorrhaged (40% mean arterial pressure for 60 minutes) and assigned to four groups (n = 7): sham, no HS; HS no resuscitation; HS+CR (shed blood plus 2 volumes Ringer's lactate); and HS+CR+DPR (20 mL clinical intraperitoneal (IP) dialysis fluid). Isotopic markers determined equilibrium distribution volumes [V(D)] in gut, liver, lung, and muscle by quantitative autoradiography (2-hour postresuscitation). Total tissue water (TTW) was determined by wet-dry weights. Extracellular water was measured from (14)C-mannitol V(D), and intravascular volume (IVV) from (131)I-labeled IgG V(D). Cellular and interstitial water volumes were calculated. HS alone decreased IVV in all tissues and TTW in gut, lung, and muscle, but not liver, compared with shams. IVV remained decreased with all resuscitations despite restoration of central hemodynamics. CR caused interstitial edema in gut, liver, and muscle, and cellular edema in lung. DPR reduced (liver, muscle) or prevented (gut, lung) these volume shifts. HS decreases IVV. HS-induced water shifts are organ-specific and prominent in gut, lung, and muscle. CR restores central hemodynamics, does not restore IVV, and alters organ-specific TTW distribution. Adjunctive DPR with IP dialysis fluid normalizes TTW and water compartment distribution and prevents edema. Combined effect of DPR and intravascular fluid replacement appears to prevent global tissue edema and improve outcomes from HS.

QS404. Adjunct Direct Peritoneal Resuscitation of Hemorrhagic Shock Decreases Endothelial Cell Inflammatory Gene Expression

Introduction: Conventional resuscitation (CR) from hemorrhagic shock (HS) primes neutrophils and activates endothelial cell-leukocyte interactions, which mediate microvascular and end-organ tissue damage. Adjunct direct peritoneal resuscitation (DPR) prevents end-organ hypoperfusion and associated tissue injury. We hypothesized that DPR with a glucose-based clinical peritoneal dialysis solution (PD) attenuates endothelial cell activation. Methods: Anesthetized rats were hemorrhaged to 40% of mean arterial pressure for 60 minutes and were randomized to 2 groups: 1) HS + CR alone (shed blood + 2 volumes normal saline); or 2) HS + CR + DPR (intraperitoneal injection of 25 mL PD at time of CR).

Postresuscitation Tissue Neutrophil Infiltration is Time-Dependent and Organ-Specific

Hemorrhagic shock with conventional resuscitation (CR) primes circulating neutrophils and activates vascular endothelium for increased systemic inflammation, superoxide release, and end-organ damage. Adjunctive direct peritoneal resuscitation (DPR) with intraperitoneal instillation of a clinical peritoneal dialysis solution decreases systemic inflammation and edema formation by enhancing tissue perfusion. The aim of this study is to determine the effect of adjunctive DPR on neutrophil and fluid sequestration. Anesthetized rats were hemorrhaged to 40% mean arterial pressure for 60 min. Animals were randomized for CR with the return of the shed blood plus two volumes of saline, or CR plus adjunctive DPR with 30 mL of intraperitoneal injection of a clinical peritoneal dialysis solution. Tissue myeloperoxidase (MPO) level, a marker of neutrophil sequestration, and total water content were assessed in the gut, lung, and liver in sham animals and at time-points 1, 2, 4, and 24 h postresuscitation. Resuscitation from hemorrhagic shock increases MPO level in all tissues in a near-linear fashion during the first 4 h following resuscitation. This occurs irrespective of the resuscitation regimen used. Tissue MPO level returned to baseline at 24 h following resuscitation except in the liver where CR and not adjunctive DPR caused a significant rebound increase. Adjunctive DPR prevented the CR-mediated obligatory fluid sequestration in the gut and lung and maintained a relative normal tissue water in these organs compared with CR alone (n = 7, F = 10.1, P < 0.01). Hemorrhagic shock and resuscitation produces time-dependent organ-specific trends of neutrophil sequestration as measured with tissue levels of myeloperoxidase, a marker of neutrophil infiltration. Modulation of the splanchnic blood flow by direct peritoneal resuscitation did not alter the time-dependent neutrophil infiltration in end-organs, suggesting a subordinate role of blood rheology in the hemorrhage-induced neutrophil sequestration. Vulnerable window for neutrophil-mediated tissue damage exists during the first 4 h following resuscitation from hemorrhagic shock in rats. Direct peritoneal resuscitation prevents the early obligatory fluid sequestration and promotes early fluid mobilization.

Cellular edema regulates tissue capillary perfusion after hemorrhage resuscitation

Hemorrhage-induced activation of endothelial cell Na+/H+ -exchanger results in cellular swelling, which physically impedes capillary filling and compromises gut perfusion. We hypothesized that correction of the vascular volume deficit by conventional resuscitation does not improve capillary filling unless cellular swelling is prevented. Also, we hypothesized that adjunctive direct peritoneal resuscitation (DPR) with topical peritoneal dialysis solution (Delflex; Fresenius USA, Inc., Ogden, Ut) enhances capillary filling and gut perfusion by mechanisms that are independent of the Na+/H+ function. In vivo intravital videomicroscopy and Doppler velocimeter were used by us to measure microvascular diameter and flow, capillary filling (index of functional capillary density, FCD), and endothelial cell function in the terminal ileum of anesthetized rats. Rats were bled to 50% mean arterial pressure for 60 min and resuscitated with the shed blood plus 2 volumes of saline (conventional resuscitation). Prevention of endothelial cell swelling was achieved with topical amiloride (specific Na+/H+ inhibitor) in the tissue bath before hemorrhage or simultaneously with conventional resuscitation. DPR was simulated by instillation of Delflex in the tissue bath as adjunctive to conventional resuscitation. Sham no hemorrhage group and a simulated DPR group that received topical amiloride treatment served as controls. Conventional resuscitation from hemorrhagic shock restored and maintained central hemodynamics but caused progressive and persistent intestinal vasoconstriction and hypoperfusion associated with low FCD and endothelial cell dysfunction. Prevention of endothelial cell swelling when combined with conventional resuscitation, preserved endothelial cell function, and restored local intestinal microvascular variables to near-prehemorrhage levels. Simulated adjunctive DPR produced rapid, sustained, and generalized vasodilation associated with restoration of endothelial cell function, and maximum recruitment of FCD independent of the Na+/H+ -exchanger function. Paradoxical endothelial cell swelling occurs early during hemorrhagic shock because of activation of the Na+/H+ exchanger. This cellular edema, which is not resolved by correction of the vascular volume deficit, explains the persistent postresuscitation endothelial cell dysfunction and gut hypoperfusion. Simulated adjunctive DPR in this study reversed endothelial cell swelling and enhanced gut perfusion by mechanisms that are independent of the Na+/H+ exchanger activity.

MECHANISMS OF DIRECT PERITONEAL RESUSCITATION-MEDIATED SPLANCHNIC HYPERPERFUSION FOLLOWING HEMORRHAGIC SHOCK

Conventional resuscitation (CR) from hemorrhagic shock causes a persistent and progressive splanchnic vasoconstriction and hypoperfusion despite hemodynamic restoration with intravenous fluid therapy. Adjunctive direct peritoneal resuscitation (DPR) with a clinical peritoneal dialysis solution instilled into the peritoneal cavity has been shown to restore splanchnic tissue perfusion, down-regulate the gut-derived exaggerated systemic inflammatory response, promote early fluid mobilization, and improve overall outcome. This study was conducted to define the molecular mechanisms of DPR-induced gut hyperperfusion after hemorrhagic shock. Male rats were bled to 50% baseline mean arterial pressure and resuscitated with the shed blood plus two volumes of saline (CR). In vivo videomicroscopy and Doppler velocimetry were used to assess terminal ileal microvascular diameters and blood flow. Direct peritoneal resuscitation animals received CR and topical application of a clinical glucose-based peritoneal dialysis solution (Delflex). Inhibitors, glibenclamide (K(+)ATP channels), N-monomethyl-L-arginine (L-NMMA) (nitric oxide synthase), 8-cyclopentyl-1,3-diprophylxanthine (DPCPX) (A1 adenosine receptor), tetrabutylammonium (K(+)Ca2+ channels), and mefenamic acid (cyclooxygenase) were topically applied (individually or in combination) with DPR according to protocol; BQ-123 (endothelin A receptor antagonist) and BQ-788 (endothelin B receptor antagonist) were used topically with CR to define the mechanism of post-CR vasoconstriction and hypoperfusion. Conventional resuscitation caused a persistent progressive intestinal vasoconstriction and hypoperfusion that can be abolished with endothelin antagonists. In contrast, adjunctive DPR caused an instantaneous sustained vasodilation and hyperperfusion. Glibenclamide or L-NMMA partially attenuated DPR-induced vasodilation, whereas the addition of DPCPX to the two inhibitors eliminated the dilation. Cyclooxygenase and K(+)Ca2+channels were not active in DPR-mediated microvascular effects. In conclusion, DPR improves splanchnic tissue perfusion by endothelium-dependent mechanisms mediated by activations of glibenclamide-sensitive K(+) channels (KATP), adenosine A1 receptor subtype activation, and nitric oxide release. Direct peritoneal resuscitation preserves endothelial dilatory functions, thereby overriding any endothelium-derived constrictor response triggered by hemorrhagic shock and CR.