Long-term local effects of intraosseous infusion on tibial bone marrow in the weanling pig model

Intraosseous contrast administration for coelomic computed tomography angiography in green iguanas (Iguana iguana): Preliminary findings show promise as an alternative to the intravenous route

Computed tomography is commonly used to evaluate the reptile coelom. One challenge in the acquisition of contrast-enhanced CT studies in reptiles is the difficulty in placing intravenous catheters due to the poor conspicuity of peripheral vessels. To overcome these limitations, intraosseous catheterization of the long bones (humerus, femur, and tibia) can be used. The purpose of this prospective study was to assess the feasibility and diagnostic value of contrast-enhanced CT of the coelom using a femoral intraosseous route for contrast administration. Twelve healthy juvenile green iguanas were enrolled. In 9 of 12 iguanas, vascular phases were obtained, providing strong, homogeneous enhancement of the arterial and venous tree concurrently. In these nine cases, Phase #1, acquired 60 s after beginning the injection of contrast medium, provided maximal contrast between the hepatic parenchyma and hepatic vasculature. In the remaining three cases, injection failure resulted from intracortical placement of the catheter tip. Histological examination of the liver, kidneys, and femur was performed to determine the pathomorphological correlates of the CT findings; in a third of patients, some degree of contrast-induced renal toxicity was documented, which in mammalians shows potential for reversibility. Four iguanas had iatrogenic structural damage to the femoral growth plates attributed to intraosseous catheter placement. A femoral intraosseous route can be used in green iguanas for iodinated contrast medium administration for CT angiography. For the greatest contrast between coelomic organs and vascular structures, at least one postcontrast acquisition 60 s after initiation of contrast administration is recommended when using this technique.

Development of Severe Combined Immunodeficient (SCID) Pig Models for Translational Cancer Modeling: Future Insights on How Humanized SCID Pigs Can Improve Preclinical Cancer Research

Within the last decade there have been several severe combined immunodeficient (SCID) pig models discovered or genetically engineered. The animals have mutations in ARTEMIS, IL2RG, or RAG1/2 genes, or combinations thereof, providing SCID pigs with NK cells, but deficient in T and B cells, or deficient in NK, T, and B cells for research studies. Biocontainment facilities and positive pressure isolators are developed to limit pathogen exposure and prolong the life of SCID pigs. Raising SCID pigs in such facilities allows for completion of long-term studies such as xenotransplantation of human cells. Ectopically injected human cancer cell lines develop into tumors in SCID pigs, thus providing a human-sized in vivo model for evaluating imaging methods to improve cancer detection and therapeutic research and development. Immunocompromised pigs have the potential to be immunologically humanized by xenotransplantation with human hematopoietic stem cells, peripheral blood leukocytes, or fetal tissue. These cells can be introduced through various routes including injection into fetal liver or the intraperitoneal (IP) space, or into piglets by intravenous, IP, and intraosseous administration. The development and maintenance of transplanted human immune cells would be initially (at least) dependent on immune signaling from swine cells. Compared to mice, swine share higher homology in immune related genes with humans. We hypothesize that the SCID pig may be able to support improved engraftment and differentiation of a wide range of human immune cells as compared to equivalent mouse models. Humanization of SCID pigs would thus provide a valuable model system for researchers to study interactions between human tumor and human immune cells. Additionally, as the SCID pig model is further developed, it may be possible to develop patient-derived xenograft models for individualized therapy and drug testing. We thus theorize that the individualized therapeutic approach would be significantly improved with a humanized SCID pig due to similarities in size, metabolism, and physiology. In all, porcine SCID models have significant potential as an excellent preclinical animal model for therapeutic testing.

CT angiography of the chest and abdomen in an emergency patient via humeral intraosseous access

A 69-year-old woman was taken to our emergency department after having been found unconscious. An intraosseous catheter was placed in the head of the right humerus due to inaccessible peripheral veins. With the suspected diagnosis of shock, pulmonary embolism, and mesenteric ischemia, a CT scan of the chest and abdomen was initiated. Pulmonary embolism and mesenteric arterial embolism could be ruled out at excellent image quality.

Ventriculosternal Shunting for the Management of Hydrocephalus: Case Report of A Novel Technique

BACKGROUND

Conventional cerebrospinal fluid diversion such as ventriculoperitoneal or ventriculoatrial shunting for the management of hydrocephalus is one of the commonest neurosurgical procedures. However, in selected patients, surgical options are limited when relative contraindications for these operations exist. A patient who underwent ventriculosternal shunting, a novel procedure, is presented with durable and successful outcomes.

OBJECTIVE

To demonstrate the feasibility, durability, and safety of ventriculosternal shunting for the management of hydrocephalus.

METHODS

A patient with end-stage renal failure and heart failure with recurrent pleural effusion suffered from post-subarachnoid hemorrhage communicating hydrocephalus. Because of the need for continuous ambulatory peritoneal dialysis and the risk of introducing excessive cardiac preloading, conventional shunting was relatively contraindicated. Ventriculosternal shunting was performed by adopting the cancellous matrix of the sternum as the anatomic receptacle for intraosseous cerebrospinal fluid absorption. After placement of the ventricular catheter in the usual manner, the distal end was inserted into the sternum.

RESULTS

There was demonstrable clinical and radiological improvement in hydrocephalus by ventriculosternal shunting. Cerebrospinal fluid intraosseous absorption by this novel procedure translated into both physical and cognitive recovery. The procedure was tolerable, effective, and durable, with the patient suffering no complications 3 years after the procedure.

CONCLUSION

Ventriculosternal shunting for the management of hydrocephalus is a feasible, safe, and durable surgical treatment option for selected patients when conventional procedures are contraindicated.

Vascular Access in Resuscitation

Intraosseous vascular access is a time-tested procedure which has been incorporated into the 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation. Intravenous access is often difficult to achieve in shock patients, and central line placement can be time consuming. Intraosseous vascular access, however, can be achieved quickly with minimal disruption of chest compressions. Newer insertion devices are easy to use, making the intraosseous route an attractive alternative for venous access during a resuscitation event. It is critical that anesthesiologists, who are often at the forefront of patient resuscitation, understand how to properly use this potentially life-saving procedure.

Intraosseous infusion into the skull: potential application for the management of hydrocephalus

OBJECT

Hydrocephalus results from abnormal cerebrospinal fluid (CSF) volumes or flow patterns. The absorption of CSF is determined largely by pressures within veins and venous sinuses in the head and adjacent to the spine. Most surgical solutions for hydrocephalus involve diversion of excess CSF into alternative absorption sites, and most of these solutions are still suboptimal. The focus of this work has been to recreate more normal CSF absorption into the dural venous sinuses without having to directly access the superior sagittal sinus (SSS).

METHODS

Intraosseous skull infusion for the purpose of accessing the SSS and the systemic venous system was tested by experimental skull infusions of tracer fluids into living large animals (14 adult pigs). Compared with control injections into an ear vein, infusions into the skull through specially designed infusion devices had similar systemic absorption characteristics. This suggested that intraosseous skull infusion in a living large animal was successful in gaining access to the SSS and systemic venous system.

CONCLUSIONS

This study constitutes the first demonstration of the success of intraosseous skull infusion in gaining rapid access to the systemic venous system and it thus opens the possibility of using this strategy for diversion of CSF back into the intracranial venous system for the treatment of hydrocephalus.

Intraosseous access in the setting of pediatric critical care transport

OBJECTIVE

To demonstrate safety and efficacy of intraosseous needle placement among health care provider groups in the setting of pediatric critical care transport.

DESIGN

Retrospective chart review.

SETTING

Pediatric critical care transports to a pediatric intensive care unit.

PATIENTS

Children undergoing pediatric critical care transport between January 1, 2000, and March 31, 2002, requiring intraosseous access before arrival to the pediatric intensive care unit.

INTERVENTIONS

Intraosseous access placed for emergent vascular access.

MEASUREMENTS AND MAIN RESULTS

During the study period, the transport team performed 1,792 transports and identified 47 patients requiring 58 intraosseous placements. These were placed by emergency medical technician-paramedics (18%), referring emergency medicine physicians (42%), and the transport team members (40%). The intraosseous needles were placed with a mean of 1.2 attempts per placement and a first attempt success rate of 78%. Main site of placement was the proximal anterior tibia (95%). Access was maintained for a mean of 5.2 hrs. The intraosseous needle was used for fluids, medications, and laboratory studies. Admitting diagnoses included respiratory distress (28%), cardiopulmonary arrest (26%), neurologic insults (17%), dehydration (15%), sepsis (11%), and other (3%). Ages ranged from 3 wks to 14 yrs (mean 2.2 yrs) and weights from 2.1 to 60 kg (mean 12.3 kg). Complications were noted in seven of 58 (12%), all limited to local edema or infiltration.

CONCLUSIONS

Intraosseous placement is frequently needed in the care of critically ill pediatric patients before they reach the pediatric intensive care unit. We have demonstrated that intraosseous needles can be placed safely with similar rates of success when comparing different provider groups. Emergency medical technician-paramedics, emergency medicine physicians, and pediatric critical care transport teams should be familiar with intraosseous placement.

Intraosseous Vascular Access in the Treatment of Chemical Warfare Casualties Assessed by Advanced Simulation: Proposed Alteration of Treatment Protocol

Current treatment protocols for chemical warfare casualties assume no IV access during the early treatment stages. Time constraints in mass casualty scenarios, impaired manual dexterity of medical personnel wearing protective gear, and victims' complex clinical presentations render standard IV access techniques impractical. A newly developed spring-driven, trigger-operated intraosseous infusion device may offer an effective solution. Sophisticated simulators were developed and used to mimic scenarios of chemical warfare casualties for assessing the feasibility of intraosseous infusion delivery. We evaluated the clinical performance of medical teams in full protective gear. The success rate in intraosseous insertion, time to completion of treatment goals, and outcome were measured in a simulated setting. Medical teams from major hospitals in Israel, designated for emergency response in a real chemical warfare mass casualty scenario, were trained in a simulated setting. All 94 participating physicians were supplied with conventional treatment modalities: only the 64 study group physicians received intraosseous devices. The simulated survival rate was 73.4% for the study group and 3.3% for the controls (P < 0.001). Treatment goals were achieved within 3.5 min (range, 1-9 min) in the study group and within >10 min for controls (P < 0.001), and the complication rate for intraosseous use was 13.8%. Personnel satisfaction with the intraosseous device was unanimous and high. New-generation intraosseous infusions have great potential value in the early treatment stages of chemical warfare casualties.

IMPLICATIONS

In a chemical warfare mass casualty scenario, the protective gear worn by medical personnel, the time constraints, and the casualties' medical condition impose limitations on the establishment of IV access during early treatment of the victims. A spring-driven, trigger-operated intraosseous infusion delivery system may offer an effective solution.

Use of intraosseous blood for repeated hematologic and biochemical analyses in healthy pigs

OBJECTIVE

To evaluate the clinical and histologic effects of repeated intraosseous (IO) needle placement in domestic pigs and determine whether blood and serum obtained intraosseously could be used for CBC and biochemical analyses.

ANIMALS

5 healthy 10-week-old pigs.

PROCEDURE

An IO needle was placed in the proximomedial region of the tibia of anesthetized pigs every other week for 2 months, and IO blood was obtained for CBC and serum biochemical analyses. Results were compared with those obtained for blood collected at the same time from the auricular vein. Two weeks after the final samples were obtained, pigs were euthanatized and tibias were processed for histologic examination.

RESULTS

Clinical abnormalities, including lameness, were not detected following IO needle placement. Histologic examination revealed only mild multifocal periosteal fibrosis and slight thickening of the periosteum without evidence of osteomyelitis. Chloride, creatinine, glucose, total protein, sodium, and BUN concentrations, alanine transaminase and gamma glutamyl transpeptidase activities, RBC count, mean corpuscular volume, and Hct did not significantly differ between IO and venous samples. However, aspartate transaminase activity, potassium, hemoglobin, and mean corpuscular hemoglobin concentrations, mean corpuscular hemoglobin, and platelet and WBC counts were significantly different.

CONCLUSION AND CLINICAL RELEVANCE

Repeated placement of 10 needles may be a safe and clinically useful method to obtain serial blood samples from domestic pigs, particularly when other vascular sites are not accessible. Intraosseous blood can be used for many of the tests comprising CBC and serum biochemical analyses.