BACKGROUND: The combination of active compression-decompression cardiopulmonary resuscitation (ACD-CPR) with an impedance threshold device (ITD) and controlled head-up positioning (AHUP-CPR) is associated with improved outcomes compared with conventional CPR (C-CPR). This study focused on the role of active decompression (AD) during AHUP-CPR.
METHODS: Farm pigs (n = 10, ∼40 kg) were anesthetized, intubated and ventilated. Physiological parameters and right ventricular pressure-volume loops were recorded continuously. Ventricular fibrillation was induced and left untreated for 10 mins, followed by automated C-CPR (2 min), ACD + ITD CPR in the flat position (2 min), and then AHUP-CPR with 3 cm of lift above the neutral chest position. After 15 min of CPR, AD was discontinued and then restarted incrementally to 4 cm. Data were analyzed with a linear mixed-effects model, using random intercepts for individual pigs.
RESULTS: Upon cessation of AD during AHUP-CPR, decompression right atrial pressure (+59%) increased (p < 0.01), whereas multiple hemodynamic parameters positively associated with perfusion, including coronary (-25%) and cerebral perfusion pressures (-11%), end-tidal CO2 (-13%), stroke volume and cardiac output (-26%), decreased immediately and significantly with p < 0.05. Restoration of AD reduced right atrial pressure and increased positive perfusion parameters in an incremental manner. Only with ≥ 3 cm of AD were all hemodynamic parameters restored to ≥ 90% of pre-AD discontinuation levels.
CONCLUSIONS: Full chest wall lift, achieved with ≥ 3 cm of AD, was needed to maintain and optimize hemodynamics during AHUP-CPR in pigs. These findings should be considered when optimizing care with this new approach.

UNASSIGNED: The purpose of this study was to determine the usefulness of active decompression and distraction sugosteogenesis (ADDS) for the management of non-syndromic odontogenic keratocysts (OKC).
UNASSIGNED: A retrospective case series study was designed and implemented. The study observed the Declaration of Helsinki on medical protocol and ethics and it was approved by the university\'s Institutional Review Board (IRB). The medical files of all patients who underwent ADDS for OKCs of the jaws at the Department of Oral and Maxillofacial Surgery of a tertiary university-affiliated medical center were reviewed. Data were collected on patient\'s age, gender, presenting signs and symptoms, lesion location, locularity, pre-ADDS, size of the lesion, post-ADDS, pain, days with bloody discharge and/or proteinaceous fluid inside the system\'s external unit, days to achieve hermetic seal, size of the lesion 2 weeks after ADDS, percentage of reduction, patient\'s complaints/complications, and follow-up period. Pre- and post-ADDS panoramic radiographs were reviewed for reduction parameters.
UNASSIGNED: Six patients, 5 males and 1 female, with an average age of 45.16 years (range 16-74 years) were studied. ADDS was performed during 4 weeks in all patients. During the therapy, the extraoral unit collected blood during 2.83 days in average. In average, after the third day, the cystic cavity started to drain a proteinaceous fluid for about 9.33 days (range 6-15 days). The average pre-ADDS Standard Lesional Area Index (SLAI) was 18.17 cm2 (range 4.40 cm2-34.58 m2) and, after 2 weeks of ADDS, the average SLAI was 5.47 cm2 (range 0.49 cm2-15.39 cm2). The average percentage of reduction, after 2 weeks, was 73.93% (range 55.49%-97.51%), which yielded an overall good reaction of OKCs to ADDS. No significant reduction of the lesions was observed from week 2 to week 4, when ADDS ceased. All lesions were enucleated after 3 months. After an average of 14 months of follow-up (12 to 17 months), no signs of recurrence have been observed.

OBJECTIVE: The objective of the present research is to describe the histologic features of the bone regenerated by means of negative pressure (sugosteogenesis) in a group of patients diagnosed with odontogenic keratocyst (OKC) who underwent active decompression and distraction sugosteogenesis (ADDS) at our institution.
METHODS: The authors designed a retrospective case series study. The population included patients with a histologic diagnosis of odontogenic keratocyst in whom active decompression and distraction sugosteogenesis followed by enucleation was performed. All patients were seen and followed from July 2019 to January 2021. The investigation was approved by the Institutional Review Board, and it observed the Declaration of Helsinki on medical protocol. Variables of this study included age, gender, anatomic location (mandible or maxilla), and histologic characteristics of the bone regenerated by means of negative pressure. Histologic features were defined as being consistent or inconsistent with viable mature bone.
RESULTS: Bone biopsies of 6 patients were considered. In total, 83.33% of patients were males and 16.66% females. One hundred percent of the bone samples subjected to negative pressure showed features of viable mature bone.
CONCLUSIONS: In this study, the histological features of the bone subjected to negative pressure demonstrated the normal characteristics of the mature, normal bone.

Motion of mitral valve during cardiac massage was examined using beagle dogs with ventricular fibrillation (n=4). Active compression-decompression cardiac massage (ACD-CM) exhibited greater peak aortic pressure than standard cardiac massage (S-CM), reverse of which was true for peak pulmonary capillary wedge pressure in each animal. Accordingly, peak aortic pressure was greater than peak pulmonary capillary wedge pressure with ACD-CM, whereas its reverse was true with S-CM. Transesophageal echocardiography revealed that mitral valve was incompletely closed with S-CM with showing regurgitation. The valve was more effectively closed during ACD-CM. These results indicate that effective closure of mitral valve during cardiac massage may increase forward blood flow, supporting \"cardiac pump theory\" rather than \"thoracic pump theory\" as a principle in dogs.

OBJECTIVE: The purpose of this study was to compare the histopathologic findings of pre- and post-active decompression of odontogenic keratocyst and to establish if such findings were consistent.
METHODS: A retrospective case series from a group of patients diagnosed with odontogenic keratocyst who underwent active decompression and distraction sugosteogenesis followed by final enucleation was designed and implemented. The dependent variable was changed in histologic diagnosis, as evaluated by an oral and maxillofacial pathologist. Other variables included age, gender, anatomic location of the lesion, and time elapsed from initial biopsy to final enucleation.
RESULTS: Six patients diagnosed with odontogenic keratocyst who underwent active decompression followed by enucleation and curettage were studied. The mean age was 45.6 years (range, 16 to 74) 83.33% were males, 16.66 females. Lesions were located in the mandible in 83.33% of cases and in the maxilla in 16.66% of cases. Post-active decompression histologic examination at the time of definitive enucleation was consistent with the initial diagnosis in 83.33% of cases.
CONCLUSIONS: The histopathological diagnosis at the time of definitive treatment by enucleation and curettage is consistent with the pre-active decompression diagnosis.

OBJECTIVE: The aim of this paper is to describe active decompression and distraction sugosteogenesis as an alternative for the management of odontogenic cystic lesions. The technique, demographics, success rate, and complications will be presented.
METHODS: A retrospective case series study design was implemented. This included patients found in our database from 2015 to 2018 with a diagnosis of any odontogenic cyst, in whom active decompression with distraction sugosteogenesis was implemented. The patient\'s medical history, demographics, radiographic characteristics of the cyst, technique/device employed, complications, and rate of success were recorded.
RESULTS: The sample consisted of 10 patients, with a mean age of 19.6 years (range 14-34). Sixty percent of all cases occurred in male patients and 40% in females. Forty percent of cases were consistent with odontogenic keratocysts with all cysts presenting in the mandible. No maxillary cases were documented. Seventy percent of such lesions were unilocular and 30% multilocular. Cortical fenestration/perforation was documented in 30% of cases and 1 pathologic fracture was seen. Active decompression was performed for an average of 37 days (range 30-50 days). With this system, radiographic resolution occurred in 1-3 months in 50% of cases, 6-12 months in 30% of cases, and 12 months in 20% of cases. Mean follow-up was 24.3 months. No recurrence was documented. Complications included fistula development (2 cases), flap dehiscence (1 case), and the size of the intraoral unit.
CONCLUSIONS: This investigation reviewed the authors\' 5-year experience employing active decompression with distraction sugosteogenesis for the management of odontogenic cystic lesions and showed that this is a reliable alternative for the management of odontogenic cysts.

The calcifying odontogenic cyst is as a benign, rare developmental odontogenic cyst with a wide range of histologic characteristics. It may present along with other odontogenic pathologies such as odontoma, ameloblastoma, adenomatoid odontogenic tumor, ameloblastic fibroma, and ameloblastic fibro-odontoma. Clinically, it can be an either intra- or extraosseous painless swelling that can produce cortical expansion. It affects mostly the anterior area of the mandible. Radiographically, it appears as a well-circumscribed unilocular radiolucency containing flecks of indistinct radiopacities. In about one third of cases, an impacted tooth is associated. In this paper, we employ a patient with an enormous calcifying odontogenic cyst to review both the pathology and active decompression and distraction sugosteogenesis, a novel technique employed to treat odontogenic entities. This dual approach usually results in an accelerated bone healing (sugosteogenesis), partial removal of the cystic epithelium, thickening of the wall, and migration of chronic inflammatory cells which triggered epithelial modulation, ultimately causing a realignment in the biologic behavior of the lesion.

BACKGROUND: Experimental active compression-decompression (ACD) CPR is associated with increased haemodynamic outcomes compared to standard mechanical chest compressions. Since no clinically available mechanical chest compression device is capable of ACD-CPR, we modified the LUCAS 2 (Physio-Control, Lund, Sweden) to deliver ACD-CPR, hypothesising it would improve haemodynamic outcomes compared with standard LUCAS CPR on pigs with cardiac arrest.
METHODS: The modified LUCAS delivering 5 cm compressions with or without 2 cm active decompression above anatomical chest level was studied in a randomized crossover design on 19 Norwegian domestic pigs. VF was electrically induced and untreated for 2 min. Each pig received ACD-CPR and standard mechanical CPR in three 180-s. phases. We measured aortic, right atrial, coronary perfusion, intracranial and oesophageal pressure, cerebral and carotid blood flow and cardiac output. Two-sided paired samples t-test was used for continuous parametric data and Wilcoxon test for non-parametric data. P < 0.05 was considered significant.
RESULTS: Due to injuries/device failure, the experimental protocol was completed in nine of 19 pigs. Cardiac output (l/min, median, (25, 75-percentiles): 1.5 (1.1, 1.7) vs. 1.1 (0.8, 1.5), p < 0.01), cerebral blood flow (AU, 297 vs. 253, mean difference: 44, 95% CI; 14-74, p = 0.01), and carotid blood flow (l/min, median, (25, 75-percentiles): 97 (70, 106) vs. 83 (57, 94), p < 0.01) were higher during ACD-CPR compared to standard mechanical CPR. Coronary perfusion pressure (CPP) trended towards higher in end decompression phase.
CONCLUSIONS: Cardiac output and brain blood flow improved with mechanical ACD-CPR and CPP trended towards higher during end-diastole compared to standard LUCAS CPR.