Fluid management for sepsis-induced hypotension in patients with advanced chronic kidney disease: a secondary analysis of the CLOVERS trial.

BACKGROUND: Early fluid management in patients with advanced chronic kidney disease (CKD) and sepsis-induced hypotension is challenging with limited evidence to support treatment recommendations. We aimed to compare an early restrictive versus liberal fluid management for sepsis-induced hypotension in patients with advanced CKD. METHODS: This post-hoc analysis included patients with advanced CKD (eGFR of less than 30 mL/min/1.73 m2 or history of end-stage renal disease on chronic dialysis) from the crystalloid liberal or vasopressor early resuscitation in sepsis (CLOVERS) trial. The primary endpoint was death from any cause before discharge home by day 90. RESULTS: Of 1563 participants enrolled in the CLOVERS trial, 196 participants had advanced CKD (45% on chronic dialysis), with 92 participants randomly assigned to the restrictive treatment group and 104 assigned to the liberal fluid group. Death from any cause before discharge home by day 90 occurred significantly less often in the restrictive fluid group compared with the liberal fluid group (20 [21.7%] vs. 41 [39.4%], HR 0.5, 95% CI 0.29-0.85). Participants in the restrictive fluid group had more vasopressor-free days (19.7 ± 10.4 days vs. 15.4 ± 12.6 days; mean difference 4.3 days, 95% CI, 1.0-7.5) and ventilator-free days by day 28 (21.0 ± 11.8 vs. 16.5 ± 13.6 days; mean difference 4.5 days, 95% CI, 0.9-8.1). CONCLUSIONS: In patients with advanced CKD and sepsis-induced hypotension, an early restrictive fluid strategy, prioritizing vasopressor use, was associated with a lower risk of death from any cause before discharge home by day 90 as compared with an early liberal fluid strategy. TRIAL REGISTRATION: NCT03434028 (2018-02-09), BioLINCC 14149.

PeriOperative Quality Initiative (POQI) international consensus statement on perioperative arterial pressure management.

Arterial pressure monitoring and management are mainstays of haemodynamic therapy in patients having surgery. This article presents updated consensus statements and recommendations on perioperative arterial pressure management developed during the 11th POQI PeriOperative Quality Initiative (POQI) consensus conference held in London, UK, on June 4-6, 2023, which included a diverse group of international experts. Based on a modified Delphi approach, we recommend keeping intraoperative mean arterial pressure ≥60 mm Hg in at-risk patients. We further recommend increasing mean arterial pressure targets when venous or compartment pressures are elevated and treating hypotension based on presumed underlying causes. When intraoperative hypertension is treated, we recommend doing so carefully to avoid hypotension. Clinicians should consider continuous intraoperative arterial pressure monitoring as it can help reduce the severity and duration of hypotension compared to intermittent arterial pressure monitoring. Postoperative hypotension is often unrecognised and might be more important than intraoperative hypotension because it is often prolonged and untreated. Future research should focus on identifying patient-specific and organ-specific hypotension harm thresholds and optimal treatment strategies for intraoperative hypotension including choice of vasopressors. Research is also needed to guide monitoring and management strategies for recognising, preventing, and treating postoperative hypotension.

Automated partial resuscitative endovascular balloon occlusion of the aorta reduces blood loss and hypotension in a highly lethal porcine liver injury model.

BACKGROUND: Partial and intermittent resuscitative endovascular balloon occlusion of the aorta (pREBOA and iREBOA, respectively) are lifesaving techniques designed to extend therapeutic duration, mitigate ischemia, and bridge patients to definitive hemorrhage control. We hypothesized that automated pREBOA balloon titration compared with automated iREBOA would reduce blood loss and hypotensive episodes over a 90-minute intervention phase compared with iREBOA in an uncontrolled liver hemorrhage swine model. METHODS: Twenty-four pigs underwent an uncontrolled hemorrhage by liver transection and were randomized to automated pREBOA (n = 8), iREBOA (n = 8), or control (n = 8). Once hemorrhagic shock criteria were met, controls had the REBOA catheter removed and received transfusions only for hypotension. The REBOA groups received 90 minutes of either iREBOA or pREBOA therapy. Surgical hemostasis was obtained, hemorrhage volume was quantified, and animals were transfused to euvolemia and then underwent 1.5 hours of automated critical care. RESULTS: The control group had significantly higher mortality rate (5 of 8) compared with no deaths in both REBOA groups, demonstrating that the liver injury is highly lethal ( p = 0.03). During the intervention phase, animals in the iREBOA group spent a greater proportion of time in hypotension than the pREBOA group (20.7% [16.2-24.8%] vs. 0.76% [0.43-1.14%]; p < 0.001). The iREBOA group required significantly more transfusions than pREBOA (21.0 [20.0-24.9] mL/kg vs. 12.1 [9.5-13.9] mL/kg; p = 0.01). At surgical hemostasis, iREBOA had significantly higher hemorrhage volumes compared with pREBOA (39.2 [29.7-44.95] mL/kg vs. 24.7 [21.6-30.8] mL/kg; p = 0.04). CONCLUSION: Partial REBOA animals spent significantly less time at hypotension and had decreased transfusions and blood loss. Both pREBOA and iREBOA prevented immediate death compared with controls. Further refinement of automated pREBOA is necessary, and controller algorithms may serve as vital control inputs for automated transfusion. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level III.

Mesenteric traction syndrome - Incidence, impact, and treatment: A systematic scoping review of the literature.

BACKGROUND: Mesenteric traction syndrome (MTS) is commonly seen during major abdominal surgery and is characterised by facial flushing, hypotension, and tachycardia 15 min into surgery. MTS also impacts the postoperative course, as severe MTS has been associated with increased postoperative morbidity. However, despite MTS being common and severe MTS causing increased postoperative morbidity, the gaps in the literature are not clearly defined. We aimed to examine the diagnostic criteria, incidence, intraoperative and postoperative impact, and potential preventative measures of MTS while highlighting potential gaps in the literature. METHODS: We followed the Prisma guidelines and performed a systematic literature search. We included only human studies examining MTS. All hits were screened for title and abstract, followed by a full-text review by at least two authors for determining eligibility for inclusion. Data were extracted and risk of bias was assessed by two independent reviewers. RESULTS: A total of 37 studies, comprising 1102 patients were included in the review. The combined incidence of MTS during open abdominal surgery was found to be 76%, with 35% developing severe MTS. It was found that the development of MTS was associated with marked haemodynamic changes. It was also found that several different subjective diagnostic criteria exist and that severe MTS was associated with increased postoperative morbidity. Furthermore, several preventative measures for protecting against MTS have been examined, but only on the incidence of MTS and not on the postoperative course. CONCLUSION: MTS occurs in 76% of patients undergoing major abdominal surgery and is associated with deleterious haemodynamic effects, which are more pronounced in patients developing severe MTS. Severe MTS is also associated with a worse postoperative outcome. However, gaps are still present in the current literature on MTS.

Preperitoneal Pelvic Packing for Hypotension Has a Greater Risk of Venous Thromboembolism Than Angioembolization: Management of Refractory Hypotension in Closed Pelvic Ring Injury.

BACKGROUND: Patients with traumatic pelvic ring injury may present with hypotension secondary to hemorrhage. Preperitoneal pelvic packing (PPP) and angioembolization (AE) are alternative interventions for management of hypotension associated with pelvic ring injury refractory to resuscitation and circumferential compression. We hypothesized that PPP may be independently associated with increased risk of venous thromboembolism (VTE) compared with AE in patients with hypotension and pelvic ring injury. METHODS: Adult patients with pelvic ring injury and hypotension managed with PPP or AE were retrospectively identified in the Trauma Quality Improvement Program (TQIP) database from 2015 to 2019. Patients were matched on a propensity score for receiving PPP based on patient, injury, and treatment factors. The primary outcome was the risk of VTE after matching on the propensity score for treatment. The secondary outcomes included inpatient clinically important deep vein thrombosis, pulmonary embolism, respiratory failure, mortality, unplanned reoperation, sepsis, surgical site infection, hospital length of stay, and intensive care unit (ICU) length of stay. RESULTS: In this study, 502 patients treated with PPP and 2,439 patients treated with AE met inclusion criteria. After propensity score matching on age, smoking status, Injury Severity Score, Tile B or C pelvic ring injury, bilateral femoral fracture, serious head injury, units of plasma and platelets given within 4 hours of admission, laparotomy, and level-I trauma center facility designation, 183 patients treated with PPP and 183 patients treated with AE remained. PPP, compared with AE, was associated with a 9.8% greater absolute risk of VTE, 6.5% greater risk of clinically important deep vein thrombosis, and 4.9% greater risk of respiratory failure after propensity score matching. CONCLUSIONS: PPP for the management of hypotension associated with pelvic ring injury is associated with higher rates of inpatient VTE events and sequelae compared with AE. LEVEL OF EVIDENCE: Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Hemodynamic Response to Fluid Boluses in Patients with Single-Ventricle Parallel Circulation.

The purpose of this study is to assess the effect of fluid bolus in response to a hypotensive episode by evaluating high-fidelity hemodynamic data obtained from children with single-ventricle anatomy and parallel circulation. Single center, retrospective analysis of hemodynamic and oximetric data after fluid bolus administrations within the first 2 weeks post-surgery. A baseline (- 60 to - 10 min), hypotensive episode (- 10 to 0 min), and response interval (0 to 60 min) were defined to quantify the dynamics of vital signs. The responses assessed include heart rate, blood pressure, oxygen saturation, oxygen extraction ratios, and pulmonary-to-systemic flow ratios. Mixed effects models were used to account for the repeated measures over the response interval. The analysis included 67 fluid boluses. There is a decrease in heart rate and an increase in blood pressure during the response in comparison to the hypotensive time. These vitals rapidly return to the baseline values. The boluses induced a significant decrease in renal and cerebral oxygen extraction ratios, with no significant change in arterial oxygen saturation or pulmonary-to-systemic flow ratio. The type of bolus (normal saline versus albumin) did not affect the response in blood pressure. However, in comparison with albumin, normal saline had a more favorable effect on the renal and cerebral oxygen extraction ratios. This study demonstrates that fluid boluses are an effective rescue medication for hypotensive episodes in children with parallel circulation by improving hemodynamics, as well as markers of oxygen delivery. The type of bolus (normal saline versus albumin) did not affect the blood pressure response. However, normal saline had a more pronounced effect on the renal and cerebral oxygen extraction ratios than albumin.

Hypotension as a marker or mediator of perioperative organ injury: a narrative review.

Perioperative hypotension has been repeatedly associated with organ injury and worse outcome, yet many interventions to reduce morbidity by attempting to avoid or reverse hypotension have floundered. In part, this reflects uncertainty as to what threshold of hypotension is relevant in the perioperative setting. Shifting population-based definitions for hypertension, plus uncertainty regarding individualised norms before surgery, both present major challenges in constructing useful clinical guidelines that may help improve clinical outcomes. Aside from these major pragmatic challenges, a wealth of biological mechanisms that underpin the development of higher blood pressure, particularly with increasing age, suggest that hypotension (however defined) or lower blood pressure per se does not account solely for developing organ injury after major surgery. The mosaic theory of hypertension, first proposed more than 60 yr ago, incorporates multiple, complementary mechanistic pathways through which clinical (macrovascular) attempts to minimise perioperative organ injury may unintentionally subvert protective or adaptive pathways that are fundamental in shaping the integrative host response to injury and inflammation. Consideration of the mosaic framework is critical for a more complete understanding of the perioperative response to acute sterile and infectious inflammation. The largely arbitrary treatment of perioperative blood pressure remains rudimentary in the context of multiple complex adaptive hypertensive endotypes, defined by distinct functional or pathobiological mechanisms, including the regulation of reactive oxygen species, autonomic dysfunction, and inflammation. Developing coherent strategies for the management of perioperative hypotension requires smarter, mechanistically solid interventions delivered by RCTs where observer bias is minimised.

A randomised controlled feasibility trial of a clinical protocol to manage hypotension during major non-cardiac surgery.

Intra-operative hypotension is a risk factor for postoperative morbidity and mortality. Minimally invasive monitors that derive other haemodynamic parameters, such as stroke volume, may better inform the management of hypotension. As a prelude to a multicentre randomised controlled trial, we conducted a single-centre feasibility trial of a protocol to treat hypotension as informed by minimally invasive haemodynamic monitoring during non-cardiac surgery. We recruited adults aged ≥40 years with cardiovascular risk factors who underwent non-cardiac surgery requiring invasive arterial pressure monitoring. Participants were randomly allocated to usual care, or a clinical protocol informed by an arterial waveform contour analysis monitor. Participants, outcome assessors, clinicians outside operating theatres and analysts were blinded to treatment allocation. Feasibility was evaluated based on: consent rate; recruitment rate; structured feedback from anaesthesia providers; and between-group differences in blood pressure, processes-of-care and outcomes. The consent rate among eligible patients was 33%, with 30 participants randomly allocated to the protocol and 30 to usual care. Anaesthesia providers rated the protocol to be feasible and acceptable. The protocol was associated with reduced fluid balance and hypotension exposure in the peri-operative setting. Postoperative complications included: acute myocardial injury in 18 (30%); acute kidney injury in 17 (28%); and surgical site infection in 7 (12%). The severity of complications was rated as moderate or severe in 25 (42%) participants. In summary, this single-centre study confirmed the feasibility of a multicentre trial to assess the efficacy and safety of a physiologically guided treatment protocol for intra-operative hypotension based on minimally invasive haemodynamic monitors.

Risk factors and prognosis in very low birth weight infants treated for hypotension during the first postnatal week from the Korean Neonatal Network.

Hypotension in the early stages of life appears in 20% of very low birth weight (VLBW) infants. The gestational age and birth weight are the risk factors highly related to the postnatal hypotension. Other risk factors slightly differ between different studies. So, we evaluated the risk factors and prognosis that are associated with infants treated with hypotension in the early stages of life, after excluding the influences of gestational age and small for gestational age (SGA). VLBW infants registered in the Korean Neonatal Network between 2013 and 2015 treated for hypotension within a week after their birth were selected as study subjects. The rest were used as a control group. Risk factors and the prevalence of severe complications, including mortality, were investigated and compared after matching for gestational age and SGA. The treatment rate for hypotension within the first postnatal week was inversely related to decreasing gestational ages and birth weights. In particular, 63.4% of preterm infants born at ≤ 24 weeks' gestation and 66.9% of those with a birth weight < 500 g were treated for hypotension within a week of birth. Regression analysis after matching showed that 1-minute Apgar score, neonatal cardiac massage or epinephrine administration, symptomatic patent ductus arteriosus, early onset sepsis, and chorioamnionitis were significantly associated with hypotension. In the hypotension group, mortality, grade 3 or higher intraventricular hemorrhage, periventricular leukomalacia, and moderate to severe bronchopulmonary dysplasia rates were significantly higher after the matching for gestational age and SGA. Hypotension during the first postnatal week is very closely related to the prematurity and the condition of the infant shortly after birth. Regular prenatal care including careful monitoring and appropriate neonatal resuscitation are very crucial to decrease the risk of hypotension in the early stages of life.

Percutaneous hepatic melphalan perfusion: Single center experience of procedural characteristics, hemodynamic response, complications, and postoperative recovery.

BACKGROUND: Percutaneous hepatic melphalan perfusion (PHMP) for the selective treatment of hepatic metastases is known to be associated with procedural hypotension and coagulation disorders. Studies on anesthetic management, perioperative course, complications, and postoperative recovery in the intensive care unit (ICU) have not been published. METHODS: In a retrospective observational study, we analyzed consecutive patients who were admitted for PHMP over a 6-year period (2016-2021). Analyses included demographic, treatment, and outcome data with regard to short-term complications until ICU discharge. RESULTS: Fifty-three PHMP procedures of 16 patients were analyzed. In all of the cases, procedure-related hypotension required the median (range) highest noradrenaline infusion rate of 0.5 (0.17-2.1) µg kg min-1 and fluid resuscitation volume of 5 (3-14) liters. Eighty-four PHMP-related complications were observed in 33 cases (62%), of which 9 cases (27%) involved grade III and IV complications. Complications included airway constriction (requiring difficult airway management), vascular catheterization issues (which resulted in the premature termination of PHMP, as well as to the postponement of PHMP and to the performance of endovascular bleeding control after PHMP), and renal failure that required hemodialysis. Discharge from the ICU was possible after one day in most cases (n = 45; 85%); however, in 12 cases (23%), prolonged mechanical ventilation was required. There were no procedure-related fatalities. CONCLUSIONS: PHMP is frequently associated with challenging cardiovascular conditions and complications that require profound anesthetic skills. For safety reasons, PHMP should only be performed in specialized centers that provide high-level hospital infrastructures and interdisciplinary expertise.

Pelvic fracture-related hypotension: A review of contemporary adjuncts for hemorrhage control.

ABSTRACT: Major pelvic hemorrhage remains a considerable challenge of modern trauma care associated with mortality in over a third of patients. Efforts to improve outcomes demand continued research into the optimal employment of both traditional and newer hemostatic adjuncts across the full spectrum of emergent care environments. The purpose of this review is to provide a concise description of the rationale for and effective use of currently available adjuncts for the control of pelvic hemorrhage. In addition, the challenges of defining the optimal order and algorithm for employment of these adjuncts will be outlined. LEVEL OF EVIDENCE: Review, level IV.

Development of a computed tomography perfusion protocol to support large animal resuscitation research.

BACKGROUND: Adequate cerebral perfusion is crucial for a positive neurological outcome in trauma; however, it is difficult to characterize in the acute setting with noninvasive methods. Intra-arterial computed tomography perfusion may offer a solution. The aim of this study was to develop an intra-arterial computed tomography perfusion protocol for resuscitation research. METHODS: The study examined intra-arterial contrast administration for computed tomography perfusion (CTP) acquisition. It consisted of three phases: intra-arterial contrast dose finding, evaluation of reproducibility, and evaluation during hypotension. Blood pressure and laser Doppler flow data were collected. In phase 1, animals underwent CTPs using several intra-arterial contrast injection protocols. In phase 2, animals underwent two CTPs 7 hours apart using the 2.5 mL/s for 3-second protocol. In phase 3, animals underwent CTPs at several pressures following a computer-controlled bleed including euvolemia and at systolic pressures of 60, 40, and 20 mm Hg. Phase 1 CTPs were evaluated for contrast-to-noise ratio. In phase 2, CTPs were compared within each animal and with laser Doppler flow using linear regression. Phase 3 CTPs were graphed against systolic pressure and fitted with a nonlinear fit. RESULTS: The protocol using 2.5mL/s for 3 seconds was optimal, demonstrating a contrast-to-noise ratio of 40.1 and a superior arterial input function curve compared with the 1 mL/s bolus. Cerebral blood flow demonstrated high concordance between baseline and end of study CTPs (R2 = 0.82, p < 0.001). Cerebral blood flow also compared moderately well against laser Doppler flow during 8 (R2 = 0.53, p = 0.03); however, laser Doppler flow did not perform well during hypovolemia, and the favorable concordance was not maintained (R2 = 0.45, p = 0.06). Cerebral blood flow was graphed against systolic blood pressure and fitted with a nonlinear fit (R2 = 0.95, p = 0.003). CONCLUSION: Computed tomography perfusion using intra-arterial contrast injection may offer a novel alternative to traditional CTP protocols that could prove a useful additional tool in the setting of resuscitation research.

Physician-staffed ambulance and increased in-hospital mortality of hypotensive trauma patients following prolonged prehospital stay: A nationwide study.

BACKGROUND: The benefits of physician-staffed emergency medical services (EMS) for trauma patients remain unclear because of the conflicting results on survival. Some studies suggested potential delays in definitive hemostasis due to prolonged prehospital stay when physicians are dispatched to the scene. We examined hypotensive trauma patients who were transported by ambulance, with the hypothesis that physician-staffed ambulances would be associated with increased in-hospital mortality, compared with EMS personnel-staffed ambulances. METHODS: A retrospective cohort study that included hypotensive trauma patients (systolic blood pressure ≤ 90 mm Hg at the scene) transported by ambulance was conducted using the Japan Trauma Data Bank (2004-2019). Physician-staffed ambulances are capable of resuscitative procedures, such as thoracotomy and surgical airway management, while EMS personnel-staffed ambulances could only provide advanced life support. In-hospital mortality and prehospital time until the hospital arrival were compared between patients who were classified based on the type of ambulance. Inverse probability weighting was conducted to adjust baseline characteristics including age, sex, comorbidities, mechanism of injury, vital signs at the scene, injury severity, and ambulance dispatch time. RESULTS: Among 14,652 patients eligible for the study, 738 were transported by a physician-staffed ambulance. In-hospital mortality was higher in the physician-staffed ambulance than in the EMS personnel-staffed ambulance (201/699 [28.8%] vs. 2287/13,090 [17.5%]; odds ratio, 1.90 [1.61-2.26]; adjusted odds ratio, 1.22 [1.14-1.30]; p < 0.01), and the physician-staffed ambulance showed longer prehospital time (50 [36-66] vs. 37 [29-48] min, difference = 12 [11-12] min, p < 0.01). Such potential harm of the physician-staffed ambulance was only observed among patients who arrived at the hospital with persistent hypotension (systolic blood pressure < 90 mm Hg on hospital arrival) in subgroup analyses. CONCLUSION: Physician-staffed ambulances were associated with prolonged prehospital stay and increased in-hospital mortality among hypotensive trauma patients compared with EMS personnel-staffed ambulance. LEVEL OF EVIDENCE: Therapeutic, level IV.