Fluid volume overload negatively influences delayed primary facial closure in open abdomen management

The Ability of Military Critical Care Air Transport Members to Visually Estimate Percent Systolic Pressure Variation

INTRODUCTION

Inappropriate fluid management during patient transport may lead to casualty morbidity. Percent systolic pressure variation (%SPV) is one of several technologies that perform a dynamic assessment of fluid responsiveness (FT-DYN). Trained anesthesia providers can visually estimate and use %SPV to limit the incidence of erroneous volume management decisions to 1-4%. However, the accuracy of visually estimated %SPV by other specialties is unknown. The aim of this article is to determine the accuracy of estimated %SPV and the incidence of erroneous volume management decisions for Critical Care Air Transport (CCAT) team members before and after training to visually estimate and utilize %SPV.

MATERIAL AND METHODS

In one sitting, CCAT team providers received didactics defining %SPV and indicators of fluid responsiveness and treatment with %SPV ≤7 and ≥14.5 defining a fluid nonresponsive and responsive patient, respectively; they were then shown ten 45-second training arterial waveforms on a simulated Propaq M portable monitor's screen. Study subjects were asked to visually estimate %SPV for each arterial waveform and queried whether they would treat with a fluid bolus. After each training simulation, they were told the true %SPV. Seven days post-training, the subjects were shown a different set of ten 45-second testing simulations and asked to estimate %SPV and choose to treat, or not. Nonparametric limits of agreement for differences between true and estimated %SPV were analyzed using Bland-Altman graphs. In addition, three errors were defined: (1) %SPV visual estimate errors that would label a volume responsive patient as nonresponsive, or vice versa; (2) incorrect treatment decisions based on estimated %SPV (algorithm application errors); and (3) incorrect treatment decisions based on true %SPV (clinically significant treatment errors). For the training and testing simulations, these error rates were compared between, and within, provider groups.

RESULTS

Sixty-one physicians (MDs), 64 registered nurses (RNs), and 53 respiratory technicians (RTs) participated in the study. For testing simulations, the incidence and 95% CI for %SPV estimate errors with sufficient magnitude to result in a treatment error were 1.4% (0.5%, 3.2%), 1.6% (0.6%, 3.4%), and 4.1% (2.2%, 6.9%) for MDs, RNs, and RTs, respectively. However, clinically significant treatment errors were statistically more common for all provider types, occurring at a rate of 7%, 10%, and 23% (all P < .05). Finally, students did not show clinically relevant reductions in their errors between training and testing simulations.

CONCLUSIONS

Although most practitioners correctly visually estimated %SPV and all students completed the training in interpreting and applying %SPV, all groups persisted in making clinically significant treatment errors with moderate to high frequency. This suggests that the treatment errors were more often driven by misapplying FT-DYN algorithms rather than by inaccurate visual estimation of %SPV. Furthermore, these errors were not responsive to training, suggesting that a decision-making cognitive aid may improve CCAT teams' ability to apply FT-DYN technologies.

Comparison of Continuous Albumin Infusion, Bolus Albumin, and Crystalloid Fluid Administration in Open-Abdomen Surgical-Trauma Patients

Background: The open abdomen (OA), an intentional lack of fascial closure following abdominal cavity opening, is utilized for various indications among surgical-trauma patients. Among intravenous fluid options, administration of albumin as a continuous infusion may improve outcomes in OA. The purpose of this study is to compare the time to abdomen closure among patients with OA according to type of fluid administration. Methods: We conducted a retrospective cohort study of adults with OA from 2012 through 2018 and stratified by intravenous fluid administration into one of three groups: continuous albumin infusion, intermittent bolus albumin, or crystalloid. The primary outcome was median time to abdomen closure. Secondary outcomes included hemodynamic parameters, length of stay (LOS), and mortality. Time to final abdomen closure was analyzed by Cox proportional hazards regression. Results: Eighty-four patients were included with 28 in each cohort. Compared to crystalloids (44.2 [interquartile range, IQR, 36.3-62.9] hours), median time to abdomen closure was significantly longer in bolus albumin (79.0 [IQR, 44.5-130.8] hours; P = .002) and continuous albumin groups (63.6 [IQR, 42.9-139.6] hours; P = .001) in Cox regression analysis. The incidence of hospital mortality was highest in the bolus albumin cohort (continuous albumin: 21.4% vs bolus albumin: 50.0% vs crystalloid: 25.0%; P = .044). All other secondary outcomes were similar between groups. Conclusions: Among patients with OA, administration of intravenous crystalloid was associated with the shortest time to abdomen closure compared to bolus or continuous albumin. Further evaluation of continuous albumin infusion in patients with OA is needed.

Increasing Use of Prophylactic Open Abdomen Therapy With Vacuum Assisted Wound Closure and Mesh Mediated Fascial Traction After Repair of Ruptured Abdominal Aortic Aneurysm

OBJECTIVE

Open abdomen therapy (OAT) is commonly used to prevent or treat abdominal compartment syndrome (ACS) in patients with ruptured abdominal aortic aneurysms (rAAAs). This study aimed to evaluate the incidence, treatment, and outcomes of OAT after rAAA from 2006 to 2021. Investigating data on resuscitation fluid, weight gain, and cumulative fluid balance could provide a more systematic approach to determining the timing of safe abdominal closure.

METHODS

This was a single centre observational cohort study. The study included all patients treated for rAAA followed by OAT from October 2006 to December 2021.

RESULTS

Seventy-two of the 244 patients who underwent surgery for rAAA received OAT. The mean age was 72 ± 7.85 years, and most were male (n = 61, 85%). The most frequent comorbidities were cardiac disease (n = 31, 43%) and hypertension (n = 31, 43%). Fifty-two patients (72%) received prophylactic OAT, and 20 received OAT for ACS (28%). There was a 25% mortality rate in the prophylactic OAT group compared with the 50% mortality in those who received OAT for ACS (p = .042). The 58 (81%) patients who survived until closure had a median of 12 (interquartile range [IQR] 9, 16.5) days of OAT and 5 (IQR 4, 7) dressing changes. There was one case of colocutaneous fistula and two cases of graft infection. All 58 patients underwent successful abdominal closure, with 55 (95%) undergoing delayed primary closure. In hospital survival was 85%. Treatment trends over time showed the increased use of prophylactic OAT (p ≤ .001) and fewer ACS cases (p = .03) assessed by Fisher's exact test. In multivariable regression analysis fluid overload and weight reduction predicted 26% of variability in time to closure.

CONCLUSION

Prophylactic OAT after rAAA can be performed safely, with a high rate of delayed primary closure even after long term treatment.

Negative Pressure Wound Therapy After Intestinal Anastomosis: A Risk Factor Analysis for Dehiscence

INTRODUCTION

Negative pressure wound therapy (NPWT) is part of the temporary abdominal closure in the treatment of patients with traumatic, inflammatory, or vascular disease. However, the use of NPWT when performing an intestinal anastomosis has been controversial. This study aimed to describe the patients managed with NPWT therapy and identify the risk factors for anastomotic dehiscence when intestinal anastomosis was performed.

METHODS

A single-center cohort study with prospectively collected databases was performed. Patients who required NPWT therapy from January 2014 to December 2018 were included. Patients were stratified according to the performance of intestinal anastomosis and according to the presence of dehiscence. Bivariate and multivariate analyses were performed for anastomotic dehiscence and mortality.

RESULTS

A total of 97 patients were included. Median age was 52 y old [interquartile range 24.5-70]. Male patients corresponded to 75.6% (n = 34) of the population. Delayed fascial closure was performed in 80% (n = 36). The risk of anastomotic dehiscence was higher in females (odds ratio (OR) 11.52 [confidence interval (CI) 1.29-97.85], P = 0.030), delayed fascial closure (OR 18.18 [CI 2.02-163.5], P = 0.010) and use of vasopressors (OR 12.04 [CI 1.22-118.47], P = 0.033). NPWT pressures >110 mmHg were evidenced in the dehiscence group with statistically significant value (OR 1.2 [0.99-2.26] p 0.04) CONCLUSIONS: There is still controversy in the use of NPWT when performing intestinal anastomosis. According to our data, the risk of dehiscence is higher in females, delayed fascial closure, use of vasopressors, and NPWT pressures >110 MMHG.

Comparative efficacy of sequential treatment and open abdomen approaches for corrosive abdominal hemorrhage due to inadequate drainage of duodenal leakage: a cohort study

BACKGROUND

Intra-abdominal bleeding resulting from inadequate drainage of duodenal leakage (DL) is typically caused by the corrosiveness of duodenal fluid. Open abdomen (OA) treatment addresses both the drainage and bleeding simultaneously. However, a sequential treatment (ST) approach involving hemostasis through transcatheter arterial embolization (TAE) followed by percutaneous drainage of source control has emerged as an alternative method. This study aimed to evaluate the prognosis of ST in cases of DL-induced intra-abdominal bleeding.

METHODS

This retrospective cohort study included 151 participants diagnosed with DL-induced intra-abdominal bleeding from January 2004 to December 2010, and January 2013 to December 2021. The ST and OA groups were established based on the treatment method applied. Propensity score-matching (PSM) matched patients in the ST group with those in the OA group.

RESULTS

Among the 151 patients, 61 (40.4%) died within 90 days after the bleeding episode. ST was associated with a lower mortality rate (28.2% vs. 51.3% adjusted odds ratio [OR] = 0.34; 95% confidence interval [CI] 0.17-0.68; P = 0.003) compared to OA. Following PSM, ST remained the only factor associated with reduced mortality (OR = 0.32; 95% CI 0.13-0.75; P = 0.009). Moreover, ST demonstrated a higher rate of initial hemostasis success before (90.1% [64/71] vs. 77.5% [62/80]; adjusted OR = 2.84; 95% CI 1.07-7.60; P = 0.04) and after PSM (94.4% [51/54] vs. 77.8% [42/54], adjusted OR = 3.85; 95% CI 2.15-16.82; P = 0.04). Additionally, ST was associated with a lower incidence of rebleeding within 90 days after the initial bleeding, before (7 vs. 23; adjusted OR 0.41; 95% CI 0.18-0.92; P = 0.03) and after PSM (5 vs. 14; adjusted OR 0.37; 95% CI 0.15-0.93; P = 0.03).

CONCLUSIONS

Applying ST involving TAE and subsequent percutaneous drainage might be superior to OA in lowering the mortality in DL-induced intra-abdominal hemorrhage.

Damage Control Surgery and Transfer in Emergency General Surgery

Selective non traumatic emergency surgery patients are targets for damage control surgery (DCS) to prevent or treat abdominal compartment syndrome and the lethal triad. However, DCS is still a subject of controversy. As a concept, DCS describes a series of abbreviated surgical procedures to allow rapid source control of hemorrhage and contamination in patients with circulatory shock to allow resuscitation and stabilization in the intensive care unit followed by delayed return to the operating room for definitive surgical management once the patient becomes physiologic stable. If appropriately applied, the DCS morbidity and mortality can be significantly reduced.

The open abdomen in trauma, acute care, and vascular and endovascular surgery: comprehensive, expert, narrative review

BACKGROUND

The open abdomen is an innovation that greatly improved surgical understanding of damage control, temporary abdominal closure, staged abdominal reconstruction, viscera and enteric fistula care, and abdominal wall reconstruction. This article provides an evidence-informed, expert, comprehensive narrative review of the open abdomen in trauma, acute care, and vascular and endovascular surgery.

METHODS

A group of 12 international trauma, acute care, and vascular and endovascular surgery experts were invited to review current literature and important concepts surrounding the open abdomen.

RESULTS

The open abdomen may be classified using validated systems developed by a working group in 2009 and modified by the World Society of the Abdominal Compartment Syndrome-The Abdominal Compartment Society in 2013. It may be indicated in major trauma, intra-abdominal sepsis, vascular surgical emergencies, and severe acute pancreatitis; to facilitate second look laparotomy or avoid or treat abdominal compartment syndrome; and when the abdominal wall cannot be safely closed. Temporary abdominal closure and staged abdominal reconstruction methods include a mesh/sheet, transabdominal wall dynamic fascial traction, negative pressure wound therapy, and hybrid negative pressure wound therapy and dynamic fascial traction. This last method likely has the highest primary fascial closure rates. Direct peritoneal resuscitation is currently an experimental strategy developed to improve primary fascial closure rates and reduce complications in those with an open abdomen. Primary fascial closure rates may be improved by early return to the operating room; limiting use of crystalloid fluids during the surgical interval; and preventing and/or treating intra-abdominal hypertension, enteric fistulae, and intra-abdominal collections after surgery. The majority of failures of primary fascial closure and enteroatmospheric fistula formation may be prevented using effective temporary abdominal closure techniques, providing appropriate resuscitation fluids and nutritional support, and closing the abdomen as early as possible.

CONCLUSION

Subsequent stages of the innovation of the open abdomen will likely involve the design and conduct of prospective studies to evaluate appropriate indications for its use and effectiveness and safety of the above components of open abdomen management.

Artificial Diuresis: Animal Studies on Efficacy and Safety of a New Miniaturized Device for Extracorporeal Ultrafiltration

INTRODUCTION

We have recently developed a new miniaturized device for extracorporeal ultrafiltration (UF) to be used in patients with fluid overload: Artificial Diuresis-1 (AD1) (Medica S.p.A., Medolla, Italy). The device has a reduced priming volume, operates at very low pressures and flow regimes, and is designed to perform extracorporeal UF at bedside. After accurate experiments were carried out in vitro, we report in this paper the results of in vivo UF sessions carried out in selected animals according to veterinary best practice.

MATERIALS AND METHODS

The AD1 kit is pre-filled with sterile isotonic solution and operates with a polysulfone mini-filter, MediSulfone (polysulfone at 50,000 Dalton). A collection bag with a volumetric scale is connected to the UF line, and the ultrafiltrate is obtained by gravity based on the height at which the ultrafiltrate collection bag is placed. Animals were prepared and anesthetized. The jugular vein was cannulated with a double-lumen catheter. Three 6-h sessions of UF were scheduled with a target fluid removal of 1,500 mL. Heparin was used as anticoagulant.

RESULTS

In all treatments, the target value of UF was obtained in the absence of major clinical or technical problems with a maximum deviation from the scheduled UF rate lower than 10%. The device resulted to be safe, reliable, accurate, and easily usable thanks to a user-friendly interface and its very small dimensions.

CONCLUSIONS

This study opens the way for clinical trials in different settings including departments with low intensity of care and even in ambulatory centers or patient's home.

Difference between delayed anastomosis and early anastomosis in damage control laparotomy affecting the infusion volume and NPWT output volume: is infusion restriction necessary in delayed anastomosis? A single-center retrospective analysis

Objectives

During temporary abdominal closure (TAC) with damage control laparotomy (DCL), infusion volume and negative-pressure wound therapy (NPWT) output volume are associated with the success and prognosis of primary fascial closure. The same may also hold true for anastomosis. The aim of this research is to evaluate whether the difference between early anastomosis and delayed anastomosis in DCL is related to infusion volume and NPWT output volume.

Methods

This single-center retrospective analysis targeted patients managed with TAC during emergency surgery for trauma or intra-abdominal sepsis between January 2011 and December 2019. It included patients who underwent repair/anastomosis/colostomy in the first surgery and patients who underwent intestinal resection in the first surgery followed by delayed anastomosis with no intestinal continuity.

Results

Seventy-three patients were managed with TAC using NPWT, including 19 cases of repair, 17 of colostomy, and 37 of anastomosis. In 16 patients (trauma 5, sepsis 11) with early anastomosis and 21 patients (trauma 16, sepsis 5) with delayed anastomosis, there was no difference in the infusion volume (p=0.2318) or NPWT output volume (p=0.7128) 48 hours after surgery. Additionally, there was no difference in the occurrence of suture failure (p=0.8428). During the second-look surgery after 48 hours, the anastomosis was further postponed for 48% of the patients who underwent delayed anastomosis. There was no difference in the infusion volume (p=0.0783) up to the second-look surgery between the patients whose delayed anastomosis was postponed and those who underwent delayed anastomosis, but there was a tendency toward a large NPWT output volume (p=0.024) in the postponed delayed anastomosis group.

Conclusion

Delayed anastomosis may be managed with the same infusion volume as that used for early anastomosis. There is also the option of postponing anastomosis if the planned delayed anastomosis is complicated.

Level of evidence

Therapeutic/Care Management, Level IV.

Open Abdomen after Two Trauma Laparotomies: Do Diuretics Help?

Data are lacking regarding the use of diuretics in facilitating closure of the open abdomen (OA). For patients with an OA after 2 laparotomies, we hypothesized that diuretic use was associated with a higher rate of primary fascial closure than no diuretic use. A retrospective review of patients with trauma laparotomies over 7 years was performed. Primary fascial closure (PFC) was defined as apposition of fascial edges without interposition mesh. Of 321 patients, 30 (9%) remained with an OA after 2 laparotomies. Prior to the third laparotomy, median cumulative fluid balance was +12.6 L. Thirteen (43%) received diuretics. Primary fascial closure rates were similar for diuretic use vs no diuretic (38% vs 59%, P = .46). Primary fascial closure was not associated with age (P = .2), gender (P = 0.7), cumulative fluid balance (P = .3), or units of packed cells (P = .4). Diuretic use in trauma patients with an OA after 2 laparotomies was not associated with successful PFC.

Fluid Overload

Fluid overload (FO) is characterized by hypervolemia, edema, or both. In clinical practice it is usually suspected when a patient shows evidence of pulmonary edema, peripheral edema, or body cavity effusion. FO may be a consequence of spontaneous disease, or may be a complication of intravenous fluid therapy. Most clinical studies of the association of FO with fluid therapy and risk of harm define it in terms of an increase in body weight of at least 5–10%, or a positive fluid balance of the same magnitude when fluid intake and urine output are measured. Numerous observational clinical studies in humans have demonstrated an association between FO, adverse events, and mortality, as have two retrospective observational studies in dogs and cats. The risk of FO may be minimized by limiting resuscitation fluid to the smallest amount needed to optimize cardiac output and then limiting maintenance fluid to the amount needed to replace ongoing normal and pathological losses of water and sodium.

Bioelectrical impedance analysis-guided fluid management promotes primary fascial closure after open abdomen: a randomized controlled trial

BACKGROUND

Fluid overload (FO) after resuscitation is frequent and contributes to adverse outcomes among postinjury open abdomen (OA) patients. Bioelectrical impedance analysis (BIA) is a promising tool for monitoring fluid status and FO. Therefore, we sought to investigate the efficacy of BIA-directed fluid resuscitation among OA patients.

METHODS

A pragmatic, prospective, randomized, observer-blind, single-center trial was performed for all trauma patients requiring OA between January 2013 and December 2017 to a national referral center. A total of 140 postinjury OA patients were randomly assigned in a 1:1 ratio to receive either a BIA-directed fluid resuscitation (BIA) protocol that included fluid administration with monitoring of hemodynamic parameters and different degrees of interventions to achieve a negative fluid balance targeting the hydration level (HL) measured by BIA or a traditional fluid resuscitation (TRD) in which clinicians determined the fluid resuscitation regimen according to traditional parameters during 30 days of ICU management. The primary outcome was the 30-day primary fascial closure (PFC) rate. The secondary outcomes included the time to PFC, postoperative 7-day cumulative fluid balance (CFB) and adverse events within 30 days after OA. The Kaplan-Meier method and the log-rank test were utilized for PFC after OA. A generalized linear regression model for the time to PFC and CFB was built.

RESULTS

A total of 134 patients completed the trial (BIA, n = 66; TRD, n = 68). The BIA patients were significantly more likely to achieve PFC than the TRD patients (83.33% vs. 55.88%, P < 0.001). In the BIA group, the time to PFC occurred earlier than that of the TRD group by an average of 3.66 days (P < 0.001). Additionally, the BIA group showed a lower postoperative 7-day CFB by an average of 6632.80 ml (P < 0.001) and fewer complications.

CONCLUSION

Among postinjury OA patients in the ICU, the use of BIA-guided fluid resuscitation resulted in a higher PFC rate and fewer severe complications than the traditional fluid resuscitation strategy.

Deresuscitation in Patients with Abdominal Sepsis Carries a Lower Mortality Rate and Less Organ Dysfunction than Conservative Fluid Management

Background: The relation between deresuscitative fluid management after the resuscitation phase and clinical outcome in patients with abdominal sepsis is not completely clear. The aim of this study was to assess the contribution of deresuscitative management to death and organ dysfunction in abdominal sepsis. Methods: Consecutive patients with abdominal sepsis requiring fluid resuscitation were included in this study. According to the fluid management given in the later stage of resuscitation, a conservative group and a deresuscitative fluid management group were compared. The primary outcome was in-hospital death, whereas secondary outcomes were categorized as organ dysfunction and other adverse events. Results: A total of 138 patients were enrolled in this study. Conservative fluid management was given to 47.8% of patients, whereas deresuscitative fluid management occurred in 52.2%. The deresuscitative strategy was associated with a markedly lower prevalence of new-onset acute kidney injury and a decrease in the duration of continuous renal replacement therapy (CRRT). There was a greater risk of needing new-onset intubation and the mechanical ventilation duration in the conservative group than in the deresuscitative group. However, the deresuscitative group did not differ from the conservative group with respect to open abdomen and intra-abdominal hypertension or new-onset abdominal compartment syndrome. The conservative treatment was associated with prolonged stays as well as a higher in-hospital mortality rate. A multivariable logistic regression model showed that deresuscitative fluid management imparts a protective effect against in-hospital death (odds ratio 4.343; 95% confidence interva1 1.466-12.866; p = 0.008), whereas septic shock, source control failure, and CRRT duration were associated with a higher mortality rate. Conclusions: Fluid balance achieved using deresuscitative treatment is correlated with better outcomes in patients with abdominal sepsis, indicating that this treatment may be useful as a therapeutic strategy.

Transcatheter Arterial Embolization in the Treatment of Abdominal Bleeding in Patients Being Treated with Open Abdomen Due to Duodenal Fistula

BACKGROUND

This study aimed to investigate the transcatheter arterial embolization (TAE) in treatment of abdominal bleeding in patients being treated with open abdomen due to duodenal fistula.

METHODS

This was a retrospective study performed at our center. From January 2005 to November 2010, all patients with abdominal bleeding were treated with surgical hemostasis (SH) and included in SH group. From January 2012 to December 2018, all patients with a bleeding were treated with TAE and included in the TAE group. Clinical data were reviewed and compared between the two groups. The effect of TAE in the management of abdominal bleeding was evaluated.

RESULTS

A total of 131 patients were enrolled, and there were 64 in the SH group and 67 in the TAE group. The success rate of hemostasis was higher in the TAE group (89.55% vs. 73.44%, adjusted OR = 4.065, 95% CI 1.336-12.336, P = 0.013). Moreover, the recognition rate of hemorrhagic vessels in the TAE group was higher (91.04 vs. 51.56; P < 0.001). The re-bleeding occurred in 20 patients, 7(11.67%) in the TAE group and 13(27.66%) in the SH group. The re-bleeding rate in SH group was higher (adjusted HR = 2.564, 95% CI 1.023-6.428, P = 0.045) CONCLUSIONS: TAE is an effective method in treatment of abdominal bleeding in patients being treated with open abdomen due to duodenal fistula.

The endothelial glycocalyx: Structure and function in health and critical illness

OBJECTIVE

To conduct a narrative review of the current literature in reference to the structure and function of the endothelial glycocalyx (EG) and its contribution to the pathophysiology of conditions relevant to the veterinary emergency and critical care clinician. Novel therapies for restoring or preserving the EG will also be discussed.

DATA SOURCES

Online databases (PubMed, CAB abstracts, Scopus) were searched between January 1st 2017 and May 1st 2017 for English language articles without publication date restriction. Keywords included EG, endothelial surface layer, degradation, syndecan-1, heparan sulfate, critical illness, sepsis, trauma, and therapeutics.

DATA SYNTHESIS

The EG is a complex and important structure located on the luminal surface of all blood vessels throughout the body. It plays an important role in normal vascular homeostasis including control of fluid exchange across the vascular barrier. Loss or degradation of the EG has an impact on inflammation, coagulation, and vascular permeability and tone. These changes are essential components in the pathophysiology of many conditions including sepsis and trauma. A substantial body of experimental animal and human clinical research over the last decade has demonstrated increased circulating concentrations of EG degradation products in these conditions. However, veterinary-specific research into the EG and critical illness is currently lacking. The utility of EG degradation products as diagnostic and prognostic tools continues to be investigated and new therapies to preserve or improve EG structure and function are under development.

CONCLUSIONS

The recognition of the presence of the EG has changed our understanding of transvascular fluid flux and the pathophysiology of many conditions of critical illness. The EG is an exciting target for novel therapeutics to improve morbidity and mortality in conditions such as sepsis and trauma.

A preliminary prospective study of patients who underwent vacuum-assisted and mesh-mediated fascial traction techniques for open abdomen management with negative fluid therapy: An observational study

It is unclear whether strategies targeting negative fluid balance are associated with facilitated early fascial closure. The present study investigated the effects of fluid removal therapy on early facial closure of open abdomen patients.A prospective study was conducted in patients who underwent open abdomen management with vacuum-assisted and mesh-mediated fascial traction technique. Therapeutic diuresis with torasemide was applied to cause negative fluid balance in the treatment group. The study and follow-up periods were 7 and 180 days, respectively. The observational indices included the intra-abdominal pressure, the number of days to closure, the type of closure, the septic complications, the duration of ventilation support, the duration of initial hospital stay, and the duration of intensive care unit (ICU) stay.A total of 27 patients were divided into the treatment (16 patients) and control (11 patients) groups. The median intra-abdominal pressure (IAP) of the patients of the control and the treatment groups was significantly lower at day 7 compared with the baseline value (P < .0001). IAP was lower in the treatment group compared with that noted in the control group, following day 4 of the fluid removal therapy (P < .05). The percentage weight loss in the treatment group was between 4.80% and 10.88%. The early closure rates were significantly higher in the treatment group compared with those in the control group (75.0% vs 18.2%, P = .0063).Fluid removal therapy combined with vacuum-assisted and mesh-mediated fascial traction provided a high early fascial closure rate for open abdomen patients.

Elastic TPU Mesh as Abdominal Wall Inlay Significantly Reduces Defect Size in a Minipig Model

Background: The open abdomen with mesh implantation, followed by early reoperation with fascial closure, is a modern surgical approach in difficult clinical situations such as severe abdominal sepsis. As early fascial closure is not possible in many cases, mesh-mediated fascial traction is helpful for conditioning of a minimized ventral hernia after open abdomen. The aim of this study was to evaluate the clinical utilization of an innovative elastic thermoplastic polyurethane mesh (TPU) as an abdominal wall inlay in a minipig model. Methods: Ten minipigs were divided in two groups, either receiving an elastic TPU mesh or a nonelastic polyvinylidene fluoride (PVDF) mesh in inlay position of the abdominal wall. After 8 weeks, mesh expansion and abdominal wall defect size were measured. Finally, pigs were euthanized and abdominal walls were explanted for histological and immunohistochemical assessment. Results: Eight weeks after abdominal wall replacement, transversal diameter of the fascial defect in the TPU group was significantly smaller than in the PVDF group (4.5 cm vs. 7.4 cm; p = 0.047). Immunhistochemical analysis showed increased Ki67 positive cells (p = 0.003) and a higher number of apoptotic cells (p = 0.047) after abdominal wall replacement with a TPU mesh. Collagen type I/III ratio was increased in the PVDF group (p = 0.011). Conclusion: Implantation of an elastic TPU mesh as abdominal wall inlay is a promising approach to reduce the size of the ventral hernia after open abdomen by mesh-mediated traction. However, this effect was associated with a slightly increased foreign body reaction in comparison to the nonelastic PVDF.

The open abdomen in trauma and non-trauma patients: WSES guidelines

Damage control resuscitation may lead to postoperative intra-abdominal hypertension or abdominal compartment syndrome. These conditions may result in a vicious, self-perpetuating cycle leading to severe physiologic derangements and multiorgan failure unless interrupted by abdominal (surgical or other) decompression. Further, in some clinical situations, the abdomen cannot be closed due to the visceral edema, the inability to control the compelling source of infection or the necessity to re-explore (as a "planned second-look" laparotomy) or complete previously initiated damage control procedures or in cases of abdominal wall disruption. The open abdomen in trauma and non-trauma patients has been proposed to be effective in preventing or treating deranged physiology in patients with severe injuries or critical illness when no other perceived options exist. Its use, however, remains controversial as it is resource consuming and represents a non-anatomic situation with the potential for severe adverse effects. Its use, therefore, should only be considered in patients who would most benefit from it. Abdominal fascia-to-fascia closure should be done as soon as the patient can physiologically tolerate it. All precautions to minimize complications should be implemented.

Peripheral Venous Waveform Analysis for Detecting Hemorrhage and Iatrogenic Volume Overload in a Porcine Model

BACKGROUND

Unrecognized hemorrhage and unguided resuscitation is associated with increased perioperative morbidity and mortality. The authors investigated peripheral venous waveform analysis (PIVA) as a method for quantitating hemorrhage as well as iatrogenic fluid overload during resuscitation.

METHODS

The authors conducted a prospective study on Yorkshire Pigs (n = 8) undergoing hemorrhage, autologous blood return, and administration of balanced crystalloid solution beyond euvolemia. Intra-arterial blood pressure, electrocardiogram, and pulse oximetry were applied to each subject. Peripheral venous pressure was measured continuously through an upper extremity standard peripheral IV catheter and analyzed with LabChart. The primary outcome was comparison of change in the first fundamental frequency (f1) of PIVA with standard and invasive monitoring and shock index (SI).

RESULTS

Hemorrhage, return to euvolemia, and iatrogenic fluid overload resulted in significantly non-zero slopes of f1 amplitude. There were no significant differences in heart rate or mean arterial pressure, and a late change in SI. For the detection of hypovolemia the PIVA f1 amplitude change generated an receiver operator curves (ROC) curve with an area under the curve (AUC) of 0.93; heart rate AUC = 0.61; mean arterial pressure AUC = 0.48, and SI AUC = 0.72. For hypervolemia the f1 amplitude generated an ROC curve with an AUC of 0.85, heart rate AUC = 0.62, mean arterial pressure AUC = 0.63, and SI AUC = 0.65.

CONCLUSIONS

In this study, PIVA demonstrated a greater sensitivity for detecting acute hemorrhage, return to euvolemia, and iatrogenic fluid overload compared with standard monitoring and SI. PIVA may provide a low-cost, minimally invasive monitoring solution for monitoring and resuscitating patients with perioperative hemorrhage.

Open Abdomen Improves Survival in Patients With Peritonitis Secondary to Acute Superior Mesenteric Artery Occlusion

BACKGROUND

Damage control surgery and open abdomen (OA) have been extensively used in the severe traumatic patients. However, there was little information when extended to a nontrauma setting. The purpose of this study was to evaluate whether the liberal use of OA as a damage control surgery adjunct improved the clinical outcome in acute superior mesenteric artery occlusion patients.

STUDY DESIGN

A single-center, retrospective cohort review was performed in a national tertiary surgical referral center.

RESULTS

Forty-four patients received OA (OA group) and 65 patients had a primary fascial closure (non-OA group) after diagnosed as peritonitis secondary to acute superior mesenteric artery occlusion from January, 2005 to June, 2016. Revascularization was achieved through endovascular aspiration embolectomy, open embolectomy, or percutaneous stent. No difference of bowel resection length was found between groups in the first emergency surgery. However, more non-OA patients (35.4%) required a second-look enterectomy to remove the residual bowel ischemia than OA patients (13.6%, P<0.05). OA was closed within a median of 7 days (4 to 15 d). There was a mean of 134 cm residual alive bowel in OA, whereas 96 cm in non-OA. More non-OA patients suffered from intra-abdominal sepsis (23.1% vs. 6.8%, P<0.01), intra-abdominal hypertension (31% vs. 0, P<0.01), and acute renal failure (53.8% vs. 31.8%, P<0.05) than OA group after surgery. Short-bowel syndrome occurred infrequently in OA than non-OA patients (9.1% vs. 36.9%, P<0.01). OA significantly decreased the 30-day (27.3% vs. 52.3%, P<0.01) and 1-year mortality rate (31.8 % vs. 61.5%, P<0.01) compared with non-OA group.

CONCLUSIONS

Liberal use of OA, as a damage control adjunct avoided the development of intra-abdominal hypertension, reduced sepsis-related complication, and improved the clinical outcomes in peritonitis secondary to acute SMA occlusion.

Open abdomen critical care management principles: resuscitation, fluid balance, nutrition, and ventilator management

The term "open abdomen" refers to a surgically created defect in the abdominal wall that exposes abdominal viscera. Leaving an abdominal cavity temporarily open has been well described for several indications, including damage control surgery and abdominal compartment syndrome. Although beneficial in certain patients, the act of keeping an abdominal cavity open has physiologic repercussions that must be recognized and managed during postoperative care. This review article describes these issues and provides guidelines for the critical care physician managing a patient with an open abdomen.

The role of open abdomen in non-trauma patient: WSES Consensus Paper

The open abdomen (OA) is defined as intentional decision to leave the fascial edges of the abdomen un-approximated after laparotomy (laparostomy). The abdominal contents are potentially exposed and therefore must be protected with a temporary coverage, which is referred to as temporal abdominal closure (TAC). OA use remains widely debated with many specific details deserving detailed assessment and clarification. To date, in patients with intra-abdominal emergencies, the OA has not been formally endorsed for routine utilization; although, utilization is seemingly increasing. Therefore, the World Society of Emergency Surgery (WSES), Abdominal Compartment Society (WSACS) and the Donegal Research Academy united a worldwide group of experts in an international consensus conference to review and thereafter propose the basis for evidence-directed utilization of OA management in non-trauma emergency surgery and critically ill patients. In addition to utilization recommendations, questions with insufficient evidence urgently requiring future study were identified.

Complications and Mortality Associated with Temporary Abdominal Closure Techniques: A Systematic Review and Meta-Analysis

Temporary abdominal closure (TAC) techniques are routinely used in the open abdomen. Ideally, they should prevent evisceration, aid in removal of unwanted fluid from the peritoneal cavity, facilitate in achieving safe definitive fascial closure, as well as prevent the development of intra-abdominal complications. TAC techniques used in the open abdomen were compared with negative pressure wound therapy (NPWT) to identify which was superior. A systematic review was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines involving Medline, Excerpta Medica, Cochrane Central Register of Controlled Trials, Cumulative Index to Nursing and Allied Health Literature, and Clinicaltrials.gov. All studies describing TAC technique use in the open abdomen were eligible for inclusion. Data were analyzed per TAC technique in the form of a meta-analysis. A total of 225 articles were included in the final analysis. A meta-analysis involving only randomized controlled trials showed that NPWT with continuous fascial closure was superior to NPWT alone for definitive fascial closure [mean difference (MD): 35% ± 23%; P = 0.0044]. A subsequent meta-analysis involving all included studies confirmed its superiority across outcomes for definitive fascial closure (MD: 19% ± 3%; P < 0.0001), perioperative (MD: -4.0% ± 2.4%; P = 0.0013) and in-hospital (MD: -5.0% ± 2.9%; P = 0.0013) mortality, entero-atmospheric fistula (MD: 22.0% ± 1.8%; P = 0.0041), ventral hernia (MD: -4.0% ± 2.4%; P = 0.0010), and intra-abdominal abscess (MD: -3.1% ± 2.1%; P = 0.0044). Therefore, it was concluded that NPWT with continuous fascial traction is superior to NPWT alone.

Techniques for Abdominal Wall Closure after Damage Control Laparotomy: From Temporary Abdominal Closure to Early/Delayed Fascial Closure-A Review

Open abdomen (OA) has been an effective treatment for abdominal catastrophes in traumatic and general surgery. However, management of patients with OA remains a formidable task for surgeons. The central goal of OA is closure of fascial defect as early as is clinically feasible without precipitating abdominal compartment syndrome. Historically, techniques such as packing, mesh, and vacuum-assisted closure have been developed to assist temporary abdominal closure, and techniques such as components separation, mesh-mediated traction, bridging fascial defect with permanent synthetic mesh, or biologic mesh have also been attempted to achieve early primary fascial closure, either alone or in combined use. The objective of this review is to present the challenges of these techniques for OA with a goal of early primary fascial closure, when the patient's physiological condition allows.

Systematic review and meta-analysis of the open abdomen and temporary abdominal closure techniques in non-trauma patients

BACKGROUND

Several challenging clinical situations in patients with peritonitis can result in an open abdomen (OA) and subsequent temporary abdominal closure (TAC). Indications and treatment choices differ among surgeons. The risk of fistula development and the possibility to achieve delayed fascial closure differ between techniques. The aim of this study was to review the literature on the OA and TAC in peritonitis patients, to analyze indications and to assess delayed fascial closure, enteroatmospheric fistula and mortality rate, overall and per TAC technique.

METHODS

Electronic databases were searched for studies describing the OA in patients of whom 50% or more had peritonitis of a non-traumatic origin.

RESULTS

The search identified 74 studies describing 78 patient series, comprising 4,358 patients of which 3,461 (79%) had peritonitis. The overall quality of the included studies was low and the indications for open abdominal management differed considerably. Negative pressure wound therapy (NPWT) was the most frequent described TAC technique (38 of 78 series). The highest weighted fascial closure rate was found in series describing NPWT with continuous mesh or suture mediated fascial traction (6 series, 463 patients: 73.1%, 95% confidence interval 63.3-81.0%) and dynamic retention sutures (5 series, 77 patients: 73.6%, 51.1-88.1%). Weighted rates of fistula varied from 5.7% after NPWT with fascial traction (2.2-14.1%), 14.6% (12.1-17.6%) for NPWT only, and 17.2% after mesh inlay (17.2-29.5%).

CONCLUSION

Although the best results in terms of achieving delayed fascial closure and risk of enteroatmospheric fistula were shown for NPWT with continuous fascial traction, the overall quality of the available evidence was poor, and uniform recommendations cannot be made.

Damage Control and the Open Abdomen: Challenges for the Nonsurgical Intensivist

BACKGROUND

As strategies in acute care surgery focus on damage control to restore physiology, intensivists spanning all disciplines care for an increasing number of patients requiring massive transfusion, temporary abdominal closures, and their sequelae.

OBJECTIVE

To equip the nonsurgical intensivist with evidence-based management principles for patients with an open abdomen after damage control surgery.

DATA SOURCE

Search of PubMed database and manual review of bibliographies from selected articles.

DATA SYNTHESIS AND CONCLUSIONS

Temporary abdominal closure improves outcomes in patients with abdominal compartment syndrome, hemorrhagic shock, and intra-abdominal sepsis but creates new challenges with electrolyte derangement, hypovolemia, malnutrition, enteric fistulas, and loss of abdominal wall domain. Intensive care of such patients mandates attention to resuscitation, sepsis control, and expedient abdominal closure.

VAWCM-Instillation Improves Delayed Primary Fascial Closure of Open Septic Abdomen

Background. Failure to achieve delayed primary fascial closure (DPFC) is one of the main complications of open abdomen (OA), certainly when abdominal sepsis is present. This retrospective cohort study aims to evaluate the effect of combined therapy of vacuum-assisted mesh-mediated fascial traction and topical instillation (VAWCM-instillation) on DPFC in the open septic abdomen. Methods. The patients with abdominal sepsis who underwent OA using VAWCM were included and divided into the instillation and noninstillation (control) groups. The DPFC rate and other outcomes were compared between the two groups. Results. Between 2007 and 2013, 73 patients with open septic abdomen were treated with VAWCM-instillation and 61 cases with VAWCM-only. The DPFC rate in the instillation group was significantly increased (63% versus 41%, P = 0.011). The mortality with OA was similar (24.6% versus 23%, P = 0.817) between the two groups. However, time to DPFC (P = 0.003) and length of stay in hospital (P = 0.022) of the survivals were significantly decreased in the instillation group. In addition, VAWCM-instillation (OR 1.453, 95% CI 1.222–4.927, P = 0.011) was an independent influencing factor related to successful DPFC. Conclusions. VAWCM-instillation could improve the DPFC rate but could not decrease the mortality in the patients with open septic abdomen.

Crystalloid and colloid therapy

Fluid therapy is a cornerstone of emergency medicine, but equine practitioners should be aware of recent developments that have modified previous recommendations. First, new emphasis on the avoidance of hyperchloremia suggests that crystalloids with a lower chloride concentration may be more appropriate for use. Second, modifications to the understanding of the Starling equation suggest that the benefits of colloids may be more limited than previously thought. In addition, the negative effects of fluid overload on morbidity and mortality are becoming increasingly recognized. Although more specific research in horses is needed, these principles are likely to apply across all species.