Improving perioperative acetaminophen administration for safer and cost-effective multimodal analgesia in pediatric surgery: A QI initiative.

Background: The use of acetaminophen in the perioperative period has emerged as an attractive option for providing safer and cost-effective analgesia in children.

Aims: The primary aim of our project was to increase the use of acetaminophen (both oral and intravenous) in the perioperative period from a baseline of 39.5% to 50% for all surgical patients within 24 months.

5-Hydroxymethylfurfural reduces skeletal muscle superoxide production and modifies force production in rats exposed to hypobaric hypoxia.

Decreased blood-tissue oxygenation at high altitude (HA) increases mitochondrial oxidant production and reduces exercise capacity. 5-Hydroxymethylfurfural (5-HMF) is an antioxidant that increases hemoglobin's binding affinity for oxygen. For these reasons, we hypothesized that 5-HMF would improve muscle performance in rats exposed to a simulated HA of ~5500 m.

Thoracic, Peripheral, and Cerebral Volume, Circulatory and Pressure Responses To PEEP During Simulated Hemorrhage in a Pig Model: a Case Study.

Positive end-expiratory pressure (PEEP) is a respiratory/ventilation procedure that is used to maintain or improve breathing in clinical and experimental cases that exhibit impaired lung function. Body fluid shift movement is not monitored during PEEP application in intensive care units (ICU), which would be interesting specifically in hypotensive patients. Brain injured and hypotensive patients are known to have compromised cerebral blood flow (CBF) autoregulation (AR) but currently, there is no non-invasive way to assess the risk of implementing a hypotensive resuscitation strategy and PEEP use in these patients.

The effect of the perfluorocarbon emulsion Oxycyte™ in an ovine model of severe decompression illness.

Background: The treatment of decompression sickness (DCS) with hyperbaric oxygen (HBO2) serves to decrease intravascular bubble size, increase oxygen (O2) delivery to tissue and enhance the elimination of inert gas. Emulsified perfluorocarbons (PFC) combined with breathing O2 have been shown to have similar effects animal models. We studied an ovine model of severe DCS treated with the intravenous PFC Oxycyte™ while breathing O2 compared to saline control also breathing O2.

Exhaled Volatile Organic Compounds Precedes Pulmonary Injury in a Swine Pulmonary Oxygen Toxicity Model.

Purpose: Inspiring high partial pressure of oxygen (FiO > 0.6) for a prolonged duration can lead to lung damage termed pulmonary oxygen toxicity (POT). While current practice is to limit oxygen exposure, there are clinical and military scenarios where higher FiO levels and partial pressures of oxygen are required.

Cardiovascular Parameters in a Swine Model of Normobaric Hypoxia Treated With 5-Hydroxymethyl-2-Furfural (5-HMF).

Introduction: The consequences of low partial pressure of O include low arterial O saturations (SaO), low blood O content (CaO), elevated mean pulmonary artery pressure (PAP), and decreased O consumption VO. 5-hydroxymethyl-2-furfural (5-HMF) binds to the N-terminal valine of hemoglobin (HgB) and increases its affinity to O. We used an instrumented, sedated swine model to study the effect of 5-HMF on cardiovascular parameters during exposure to acute normobaric hypoxia (NH).

Blood transfusions, blood storage, and correlation with elevated pulmonary arterial pressures.

Background: The aim of this study was to determine if transfusion with RBCs is associated with a rise in mean pulmonary artery pressure (MPAP) and whether such a rise is influenced by the duration of RBC storage.

Study Design And Methods: A retrospective chart review of intensive care unit patients with pulmonary artery catheters was conducted at two military medical centers.

Results: RBC transfusion is associated with a sustained (≥4 hours) statistically significant 2- to 3-mm Hg rise in MPAP relative to both pretransfusion levels (p < 0.

The Influence of CO and Exercise on Hypobaric Hypoxia Induced Pulmonary Edema in Rats.

Individuals with a known susceptibility to high altitude pulmonary edema (HAPE) demonstrate a reduced ventilation response and increased pulmonary vasoconstriction when exposed to hypoxia. It is unknown whether reduced sensitivity to hypercapnia is correlated with increased incidence and/or severity of HAPE, and while acute exercise at altitude is known to exacerbate symptoms the effect of exercise training on HAPE susceptibility is unclear. To determine if chronic intermittent hypercapnia and exercise increases the incidence of HAPE in rats.

Perfluorocarbon in Delayed Recompression with a Mixed Gender Swine Model of Decompression Sickness.

Introduction: Perfluorocarbons (PFC) are fluorinated hydrocarbons that dissolve gases to a much greater degree than plasma and hold promise in treating decompression sickness (DCS). The efficacy of PFC in a mixed gender model of DCS and safety in recompression therapy has not been previously explored.

Methods: Swine (25 kg; N = 104; 51 male and 53 female) were randomized into normal saline solution (NSS) or PFC emulsion treatment groups and subjected to compression on air in a hyperbaric chamber at 200 fsw for 31 min.

Propranolol Effects on Decompression Sickness in a Simulated DISSUB Rescue in Swine.

Introduction: Disabled submarine (DISSUB) survivors may face elevated CO2 levels and inert gas saturation, putting them at risk for CO2 toxicity and decompression sickness (DCS). Propranolol was shown to reduce CO2 production in an experimental DISSUB model in humans but its effects on DCS in a DISSUB rescue scenario are unknown. A 100% oxygen prebreathe (OPB) reduces DCS incidence and severity and is incorporated into some DISSUB rescue protocols.

The Emulsified PFC Oxycyte Improved Oxygen Content and Lung Injury Score in a Swine Model of Oleic Acid Lung Injury (OALI).

Purpose: Perfluorocarbons (PFCs) can transport 50 times more oxygen than human plasma. Their properties may be advantageous in preservation of tissue viability in oxygen-deprived states, such as in acute lung injury. We hypothesized that an intravenous dose of the PFC emulsion Oxycyte would improve tissue oxygenation and thereby mitigate the effects of acute lung injury.

Brain hypoxia is exacerbated in hypobaria during aeromedical evacuation in swine with traumatic brain injury.

Background: There is inadequate information on the physiologic effects of aeromedical evacuation on wounded war fighters with traumatic brain injury (TBI). At altitudes of 8,000 ft, the inspired oxygen is lower than standard sea level values. In troops experiencing TBI, this reduced oxygen may worsen or cause secondary brain injury.

The effect of the perfluorocarbon emulsion Oxycyte on platelet count and function in the treatment of decompression sickness in a swine model.

Decompression from elevated ambient pressure is associated with platelet activation and decreased platelet counts. Standard treatment for decompression sickness (DCS) is hyperbaric oxygen therapy. Intravenous perfluorocarbon (PFC) emulsion is a nonrecompressive therapy being examined that improves mortality in animal models of DCS.

Dodecafluoropentane (DDFPe) and decompression sickness-related mortality in rats.

Introduction: Perfluorocarbon (PFC) formulations can be a useful adjunct treatment for decompression sickness (DCS) when staged decompression procedures cannot be followed due to time constraints or lack of equipment. The benefit of PFC treatment is believed to result from its ability to transport more dissolved gas than can be transported by blood alone. Dodecylfluoropentane (DDFPe) is a unique nanodroplet compound that expands into a gaseous state when exposed to physiological temperatures, resulting in a higher dissolved gas-carrying capacity than standard PFC formulations.

Decompression and decompression sickness.

The ever-present desire of humankind to explore new limits introduced us to the syndrome of decompression sickness (DCS). This broad overview of DCS is aimed at its pathophysiology and basics of therapeutic strategies. After a brief explanation of decompression theory, historical vignettes will serve to inform the practical application of our increasing understanding of DCS risks.

The intravenous perfluorocarbon emulsion Oxycyte does not increase hyperbaric oxygen-related seizures in a non-sedated swine model.

Purpose: Standard treatment for decompression sickness (DCS) is recompression therapy with hyperbaric oxygen (HBO). Non-recompressive therapies are needed to address mass casualty scenarios such as a disabled submarine rescue or DCS therapy in remote environments. Intravenously delivered perfluorocarbon (PFC) emulsions improve blood oxygen content and decrease mortality in several animal models of DCS.

Heat shock stress prior to hyperbaric oxygen exposure in rats.

Introduction: Heat shock proteins (HSPs) and nuclear factor-kappa B (NF-kappaB) have been established as important mediators in lung injury; however, their role in preventing pulmonary toxicity from hyperbaric oxygen (HBO) has not been evaluated.

Methods: We aimed to study the effects of heat shock (HS) injury on hyperbaric hyperoxic lung injury (HHLI) in a rat model and identify a mechanism of protection by evaluating HSP 27 and HSP 70 mRNA and protein levels, NF-kappaB p65, lung injury and oxidative parameters. By varying the times between HS and exposure to HBO, the pathways of interaction between HSPs and NF-kappaB will be further clarified.

The autonomic effects of cardiopulmonary decompression sickness in swine using principal dynamic mode analysis.

Methods to predict onset of cardiopulmonary (CP) decompression sickness (DCS) would be of great benefit to clinicians caring for stricken divers. Principal dynamic mode (PDM) analysis of the electrocardiogram has been shown to provide accurate separation of the sympathetic and parasympathetic tone dynamics. Nine swine (Sus scrofa) underwent a 15-h saturation dive at 184 kPa (60 ft.

Vigabatrin prevents seizure in swine subjected to hyperbaric hyperoxia.

Oxygen is the most widely used therapeutic strategy to prevent and treat decompression sickness (DCS). Oxygen prebreathe (OPB) eliminated DCS in 20-kg swine after rapid decompression from saturation at 60 feet of seawater (fsw). However, hyperbaric oxygen (HBO) has risks.

Interrupted oxygen pre-breathing and decompression outcomes in swine.

Background: Rescue from a disabled submarine may result in substantial risk for severe decompression sickness (DCS) among survivors. Oxygen prebreathe (OPB) before rapid decompression has been shown to significantly reduce risk or delay onset for severe DCS in animals. However, the duration of this benefit remains unknown and might even be lost if a delay between the prebreathe period to initiation of recompression therapy allows for nitrogen reaccumulation.

Brain oxygenation and CNS oxygen toxicity after infusion of perfluorocarbon emulsion.

Intravenous perfluorocarbon (PFC) emulsions, administered with supplemental inspired O(2), are being evaluated for their ability to eliminate N(2) from blood and tissue prior to submarine escape, but these agents can increase the incidence of central nervous system (CNS) O(2) toxicity, perhaps by enhancing O(2) delivery to the brain. To assess this, we infused a PFC emulsion (Oxycyte, 6 ml/kg iv) into anesthetized rats and measured cerebral Po(2) and regional cerebral blood flow (rCBF) in cortex, hippocampus, hypothalamus, and striatum with 100% O(2) at 1, 3, or 5 atmospheres absolute (ATA). At 1 ATA, brain Po(2) stabilized at >20 mmHg higher in animals infused with PFC emulsion than in control animals infused with saline, and rCBF fell by ~10%.

Oxygen breathing accelerates decompression from saturation at 40 msw in 70-kg swine.

Introduction: Submarine disaster survivors can be transferred from a disabled submarine at a pressure of 40 meters of seawater (msw) to a new rescue vehicle; however, they face an inherently risky surface interval before recompression and an enormous decompression obligation due to a high likelihood of saturation. The goal was to design a safe decompression protocol using oxygen breathing and a trial-and-error methodology. We hypothesized that depth, timing, and duration of oxygen breathing during decompression from saturation play a role to mitigate decompression outcomes.

Intravenous perfluorocarbon after onset of decompression sickness decreases mortality in 20-kg swine.

Introduction: Decompression sickness (DCS) occurs when bubbles form due to pressure decreases with severity ranging from trivial to fatal. Standard treatment requires a hyperbaric chamber, not likely to be available at remote sites or during a disabled submarine escape or rescue. Alternative (non-recompressive) treatments are needed.