Hyperacute experimental model of rat lung transplantation using a coronary shunt cannula

BACKGROUND Lung transplantation is a well-established treatment of end-stage lung disease.A rodent model is an inexpensive way to collect biological data from a living model after lung transplantation.However,mastering the surgical technique takes time owing to the small organ size.AIM To conduct rat lung transplantation using a shunt cannula(SC)or modified cannula(MC)and assess their efficacy.METHODS Rat lung transplantation was performed in 11 animals in the SC group and 12 in the MC group.We devised a method of rat lung transplantation using a coronary SC for coronary artery bypass surgery as an anastomosis of pulmonary arteri-ovenous vessels and bronchioles.The same surgeon performed all surgical proce-dures in the donor and recipient rats without using a magnifying glass.The success rate of lung transplantation,operating time,and PaO2 values were com-pared after 2-h reperfusion after transplantation.RESULTS Ten and 12 lungs were successfully transplanted in the SC and MC groups,respectively.In the SC group,one animal had cardiac arrest within 1 h after reperfusion owing to bleeding during pulmonary vein anastomosis.The opera-ting time for the removal of the heart-lung block from the donor and preparation of the left lung graft was 26.8±2.3 and 25.7±1.3 min in the SC and MC groups,respectively(P=0.21).The time required for left lung transplantation in the recipients was 37.5±2.8 min and 35.9±1.4 min in the SC and MC groups,respectively(P=0.12).PaO2 values at 2 h after reperfusion were 456.2±25.5 and INTRODUCTION Lung transplantation is a well-established treatment of end-stage lung disease.Many immune and non-immune mech-anisms in lung transplantation are highly complex,and post-transplant complications such as infections and primary and chronic lung allograft dysfunction must be reduced to improve survival.Therefore,there is a need for immunological and pathophysiological analyses using animal lung transplantation models.The rat lung transplantation model was first reported in 1971[1],followed by the Mizuta Cuff model[2]in 1989.Since then,various improvements in surgical techniques,cuffs,and instruments have been reported[3-7].The advantage of using a rodent model is that it permits inexpensive collection of biological data from a living model after lung transplantation.Although trained surgeons can perform the transplantation procedure,mastering the surgical technique takes time due to the small size of the organs.The risks associated with this technique include damage to the vulnerable pulmonary artery(PA)and pulmonary vein(PV)vessel walls during anastomosis,as well as stenosis of the anastomotic site.We developed an anastomotic technique using a coronary shunt cannula(SC)for cardiac coronary artery bypass surgery as an alternative to the previously reported cuff method[2-6].This method enables anastomosis by inserting and ligating a cannula into the lumen of the PA,PV,and bronchus(Br),which is simpler and more reliable than conventional methods.This study aimed to determine problems with rat lung transplantation using the SC,develop an improved cannula,and investigate its utility.RESULTS After creating 11 lung transplantation model animals in the SC group and 12 in the MC group,all animals underwent reperfusion.One animal in the SC group had cardiac arrest 1 h after reperfusion due to hemorrhage caused by vessel wall injury during PV anastomosis.Two hours after reperfusion,we visually confirmed the maintenance of recipient hemody-namics and blood flow in the graft pulmonary cannula in 10 animals in the SC group and 12 in the MC group.The operating time for the removal of the heart-lung block from the donor and graft lung creation was 26.8±2.3 min in the SC group and 25.7±1.3 min in the MC group(P=0.21,Table 1).The duration for left lung transplantation into the recipient was 37.5±2.8 min in the SC group and 35.9±1.4 min(P=0.12,Table 1)in the MC group.Although no significant difference was found between the SC and MC groups,animals in the MC group experienced a slightly shorter operating time,smoother surgical technique,and less stressful procedure for the surgeons compared with those in the SC group.The graft lung coloration(Grade 1/2/3)after reperfusion was 0/2/8(SC group)and 0/2/10(MC group),and all grafts were reported to be successful,except in one animal in the SC group that had cardiac arrest(Table 2).The PaO2 values after 2 h of reperfusion were 456.2±25.5 mmHg in the SC group and 461.2±21.5 mmHg in the MC group(P=0.63,Table 3),showing no significant difference between the groups.

Innominate Artery Cannulation Access in Pediatric Patients Undergoing Redo Sternotomy

Redo sternotomy in pediatric patients can be complicated due to the unsuitability of many arterial cannulation sites for the pediatric population. Innominate artery cannulation provides a safe and easily reproducible alternative and prevents many of the disadvantages seen in femoral and axillary artery cannulation. Its use in pediatric cardiac surgery has seen a rise [1]. Herein, we describe the technique for innominate artery cannulation in pediatric patients undergoing redo sternotomy and review our experience with the technique.

Comparison of two supplemental oxygen methods during gastroscopy with propofol mono-sedation in patients with a normal body mass index

BACKGROUND Hypoxemia due to respiratory depression and airway obstruction during upper gastrointestinal endoscopy with sedation is a common concern.The Wei nasal jet tube(WNJT)is a new nasopharyngeal airway with the ability to provide supraglottic jet ventilation and oxygen insufflation via its built-in wall channel.The available evidence indicates that with a low oxygen flow,compared with nasal cannula,the WNJT does not decrease the occurrence of hypoxemia during upper gastrointestinal endoscopy with propofol sedation.To date,there has been no study assessing the performance of WNJT for supplemental oxygen during upper gastrointestinal endoscopy with sedation when a moderate oxygen flow is used.AIM To determine whether the WNJT performs better than the nasal prongs for the prevention of hypoxemia during gastroscopy with propofol mono-sedation when a moderate oxygen flow is provided in patients with a normal body mass index.METHODS This study was performed in 291 patients undergoing elective gastroscopy with propofol mono-sedation.Patients were randomized into one of two groups to receive either the WNJT(WNJT group,n=147)or the nasal cannula(nasal cannula group,n=144)for supplemental oxygen at a 5-L/min flow during gastroscopy.The lowest SpO2 during gastroscopy was recorded.The primary endpoint was the incidence of hypoxemia or severe hypoxemia during gastroscopy.RESULTS The total incidence of hypoxemia and severe hypoxemia during gastroscopy was significantly decreased in the WNJT group compared with the nasal cannula group(P=0.000).The lowest median SpO2 during gastroscopy was significantly higher(98%;interquartile range,97-99)in the WNJT group than in the nasal cannula group(96%;interquartile range,93-98).Epistaxis by device insertion in the WNJT group occurred in 7 patients but stopped naturally without any treatment.The two groups were comparable in terms of the satisfaction of physicians,anesthetists and patients.CONCLUSION With a moderate oxygen flow,the WNJT is more effective for the prevention of hypoxemia during gastroscopy with propofol mono-sedation compared with nasal prongs,but causing slight epistaxis in a few patients.

High-flow nasal cannula oxygen therapy and noninvasive ventilation for preventing extubation failure during weaning from mechanical ventilation assessed by lung ultrasound score: A single-center randomized study

BACKGROUND: We sought to demonstrate the superiority of a targeted therapy strategy involving high-flow nasal cannula oxygen(HFNCO_(2)) therapy and noninvasive ventilation(NIV) using lung ultrasound score(LUS) in comparison with standard care among patients in the intensive care unit(ICU) who undergo successful weaning to decrease the incidence of extubation failure at both 48 hours and seven days.METHODS: During the study period, 98 patients were enrolled in the study, including 49 in the control group and 49 in the treatment group. Patients in the control group and patients with an LUS score <14 points(at low risk of extubation failure) in the treatment group were extubated and received standard preventive care without NIV or HFNCO_(2). Patients with an LUS score ≥14 points(at high risk of extubation failure) in the treatment group were extubated with a second review of the therapeutic optimization to identify and address any persisting risk factors for postextubation respiratory distress;patients received HFNCO2 therapy combined with sessions of preventive NIV(4-8 hours per day for 4-8 sessions total) for the first 48 hours after extubation.RESULTS: In the control group, 13 patients had the LUS scores ≥14 points, while 36 patients had scores <14 points. In the treatment group, 16 patients had the LUS scores ≥14 points, while 33 patients had scores <14 points. Among patients with the LUS score ≥14 points, the extubation failure rate within 48 hours was 30.8% in the control group and 12.5% in the treatment group, constituting a statistically significant difference(P<0.05). Conversely, among patients with an LUS score <14 points, 13.9% in the control group and 9.1% in the treatment group experienced extubation failure(P=0.61). The length of ICU stay(9.4±3.1 days vs. 7.2±2.4 days) was significantly different and the re-intubation rate(at 48 hours: 18.4% vs. 10.2%;seven days: 22.4% vs. 12.2%) significantly varied between the two groups(P<0.05). There was no significant difference in the 28-day mortality rate(6.1% vs. 8.2%) between the control and treatment groups.CONCLUSIONS: Among high-risk adults being weaned from mechanical ventilation and assessed by LUS, the NIV+HFNCO_(2) protocol does not lessen the mortality rate but reduce the length of ICU stay, the rate of extubation failure at both 48 hours and seven days.

Experimental Study of Cavitation Phenomenon in a Centrifugal Blood Pump Induced by the Failure of Inlet Cannula

Cavitation of centrifugal blood pump is a serious problem accompany with the blocking failure of short inlet cannula. However, hardly any work has been seen in published literature on this complex cavitation phenomenon caused by the coupling effect of inlet cannula blocking and pumps suction. Even for cavitation studies on ordinary centrifugal pumps, similar researches on this issue are rare. In this paper, the roles of throttling, rotation speed and fluid viscosity on bubble inception and intensity in a centrifugal blood pump are studied, on the basis of experimental observations. An adjustable throttle valve installed just upstream blood pump inlet is used to simulate the throttling effect of the narrowed inlet cannula. The rotation speed is adjusted from 2 600 r/rain to 3 200 r/min. Glycerin water solutions are used to investigate the influences of kinetic viscosity. Bubbles are recorded with a high-speed video camera. Direct observation shows that different from cavitation in industrial centrifugal pumps, gas nuclei appears at the nearby of vane leading edges while throttling is light, then moves upstream to the joint position of inlet pipe and pump with the closing of the valve. It＇s found that the critical inlet pressure, obtained when bubbles are first observed, decreases linearly with viscosity and the slope is independent with rotation speeds; the critical inlet pressure and the inlet extreme pressure which is obtained when the throttle valve is nearly closed, fall linearly with rotation speed respectively and the relative pressure between them is independent with rotation speed and fluid viscosity. This paper studies experimentally on cavitation in centrifugal blood pump that caused by the failure of assembled short inlet cannula, which mav beneficial the desima of centrifugal blood Dumo with inlet cannula.

High-flow nasal cannula oxygen therapy during anesthesia recovery for older orthopedic surgery patients: A prospective randomized controlled trial

BACKGROUND Hypoxemia is a common complication in older patients during postoperative recovery and can cause pulmonary complications.Therefore,reducing the incidence of postoperative hypoxemia is a clinical concern.AIM To investigate the clinical efficacy of high-flow nasal cannula oxygen(HFNCO)in the resuscitation period of older orthopedic patients.METHODS In this prospective randomized controlled trial,60 older patients who underwent orthopedic surgery under general anesthesia were randomly divided into two groups:those who used conventional face mask and those who used HFNCO.All patients were treated with 60%oxygen for 1 h after extubation.Patients in the conventional face mask group were treated with a combination of air(2 L)and oxygen(2 L)using a traditional mask,whereas those in the HFNCO group were treated with HFNCO at a constant temperature of 34℃ and flow rate of 40 L/min.We assessed the effectiveness of oxygen therapy by monitoring the patients’arterial blood gas,peripheral oxygen saturation,and postoperative complications.RESULTS The characteristics of the patients were comparable between the groups.One hour after extubation,patients in HFNCO group had a significantly higher arterial partial pressure of oxygen(paO_(2))than that of patients in conventional face mask group(P<0.001).At extubation and 1 h after extubation,patients in both groups showed a significantly higher arterial partial pressure of carbon dioxide(paCO_(2))than the baseline levels(P<0.001).There were no differences in the saturation of peripheral oxygen,paO_(2),and paCO_(2) between the groups before anesthesia and before extubation(P>0.05).There were statistically significant differences in paO_(2) between the two groups before anesthesia and 1 h after extubation and immediately after extubation and 1 h after extubation(P<0.001).However,there were no significant differences in the oxygen tolerance score before leaving the room,airway humidification,and pulmonary complications 3 d after surgery between the two groups(P>0.05).CONCLUSION HFNCO can improve oxygen partial pressure and respiratory function in elderly patients undergoing orthopedic surgery under general endotracheal anesthesia.Thus,HFNCO can be used to prevent postoperative hypoxemia.

Drug delivery interfaces:A way to optimize inhalation therapy in spontaneously breathing children

There are several different types of drug delivery interfaces available on the market.Using the right interface for aerosol drug delivery to children is essential for effective inhalation therapy.However,clinicians usually focus on selecting the right drug-device combination and often overlook the importance of interface selection that lead to suboptimal drug delivery and therapeutic response in neonates and pediatrics.Therefore,it is necessary to critically assess each interface and understand its advantage and disadvantages in aerosol drug delivery to this patient population.The purpose of this paper is to provide a critical assessment of drug delivery interfaces used for the treatment of children with pulmonary diseases by emphasizing advantages and problems associated with their use during inhalation therapy.

Clinical characteristics and outcomes associated with nasal intermittent mandatory ventilation in acute pediatric respiratory failure

AIM To characterize the clinical course and outcomes of nasal intermittent mandatory ventilation(NIMV) use in acute pediatric respiratory failure.METHODS We identified all patients treated with NIMV in the pediatric intensive care unit(PICU) or inpatient general pediatrics between January 2013 and December 2015 at two academic centers.Patients who utilized NIMV with other modes of noninvasive ventilation during the same admission were included.Data included demographics,vital signs on admission and prior to initiation of NIMV,pediatric risk of mortality Ⅲ(PRIsM-Ⅲ) scores,complications,respiratory support characteristics,PICU and hospital length of stays,duration of respiratory support,and complications.Patients who did not require escalation to mechanical ventilation were defined as NIMV responders;those who required escalation to mechanical ventilation(MV) were defined as NIMV nonresponders.NIMV responders were compared to NIMV non-responders.RESULTS Forty-two patients met study criteria.six(14%) failed treatment and required MV.The majority of the patients(74%) had a primary diagnosis of bronchiolitis.The median age of these 42 patients was 4 mo(range 0.5-28.1 mo,IQR 7,P = 0.69).No significant difference was measured in other baseline demographics and vitals on initiation of NIMV;these included age,temperature,respiratory rate,O2 saturation,heart rate,systolic blood pressure,diastolic blood pressure,and PRIsM-Ⅲ scores.The duration of NIMV was shorter in the NIMV nonresponder vs NIMV responder group(6.5 h vs 65 h,P < 0.0005).Otherwise,NIMV failure was not associated with significant differences in PICU length of stay(LOs),hospital LOs,or total duration of respiratory support.No patients had aspiration pneumonia,pneumothorax,or skin breakdown.CONCLUSION Most of our patients responded to NIMV.NIMV failure is not associated with differences in hospital LOs,PICU LOs,or duration of respiratory support.

Efficacy of high-flow nasal cannula on acute exacerbation of chronic obstructive pulmonary disease: A meta-analysis

Objective:To systematically evaluate the efficacy and feasibility of high-flow nasal cannula(HFNC)on patients with acute exacerbation of chronic obstructive pulmonary disease(AECOPD).Methods:Systematic searches on PubMed,Web of Science,the Cochrane Library,Embase,CBM(Chinese Biomedicine Database),CNKI(China National Knowledge Infrastructure),Wanfang Database and VIP were performed for randomized controlled trials(RCTs)which explored the effects of HFNC on patients with AECOPD.The retrieval time was from the establishment of each database to July 2019.RevMan5.3 software was used for statistical analysis.Results:A total of 12 articles were included,involving 812 patients.The results showed that:(1)Compared with conventional oxygen therapy,HFNC could improve patients'arterial partial oxygen pressure(PaO2)(MD=12.70,95%CI(7.00,18.40),Z=4.37,P<0.0001),reduce partial arterial blood carbon dioxide(PaCO2)(MD=-10.99,95%CI(-14.42,-7.55),Z=6.26,P<0.00001)and reduce endotracheal intubation rate(OR=0.19,95%CI(0.04,0.93),Z=2.05,P=0.04),shorten the hospitalization time(SMD=-0.74,95%CI(-1.11,-0.37),Z=3.95,P<0.0001).(2)Compared with non-invasive positive pressure ventilation,it has fewer adverse reactions(OR=0.18,95%CI(0.09,0.35),Z=5.08,P<0.00001)and shorter hospital stay(SMD=-0.57,95%CI(-0.90,-0.23),Z=3.33,P=0.0009).Conclusion:HFNC can improve the patients’hypoxia symptoms and CO2 retention,reduce the rate of tracheal intubation,and alleviate adverse reactions.However,Limited by the quality and region of the included studies,more high-quality are needed to test it.

End-of-life home care of an interstitial pneumonia patient supported by high-flow nasal cannula therapy:A case report

BACKGROUND High-flow nasal cannula(HFNC)therapy and morphine continuous subcutaneous infusion(CSI)have been used to ameliorate dyspnea in non-cancer patients with end-stage respiratory diseases,including chronic obstructive pulmonary disease and interstitial pneumonia,primarily in hospital settings.However,it is rare to perform home-based medical treatment using these.We observe a case to assess the feasibility of this treatment strategy.CASE SUMMARY Here,we report a case of a 75-year-old man who was diagnosed with interstitial pneumonia 11 years ago and was successfully nursed at home during his terminal phase for over 10 mo without hospitalization,by introducing domiciliary uses of HFNC and morphine CSI with a patient-controlled analgesia device.CONCLUSION Active utilization of HFNC and morphine CSI with patient-controlled analgesia device would substantiate successful end-of-life palliative home care of idiopathic interstitial pneumonia patients.

A Prospective Study to Compare Routine versus Need Based Change of IV Cannula on Development of Infusion Phlebitis in Adult Surgical Patients

（IV） Intravenous therapy is one of the most commonly performed procedures in hospitalized patients yet phlebitis affects 27% to 70% of all patients receiving IV therapy. The incidence of phlebitis has proved to be a menace in effective care of surgical patients, delaying their recovery and increasing duration of hospital stay and cost. The recommendations for reducing its incidence and severity have been varied and of questionable efficacy. The current study was undertaken to evaluate whether elective change of IV cannula at fixed intervals can have any impact on incidence or severity of phlebitis in surgical patients. All patients admitted to the Department of Surgery, SMIMS undergoing IV cannula insertion, fulfilling the selection criteria and willing to participate in the study, were segregated into two random groups prospectively： Group A wherein cannula was changed electively after 24 hours into a fresh vein preferably on the other upper limb and Group B wherein IV caunula was changed only on development of phlebitis or leak i.e. need-based change. The material/brand and protocol for insertion of IV cannula were standardised for all patients, including skin preparation, insertion, fixation and removal. After carmulation, assessment was made after 6 hours, 12 hours and every 24 hours thereafter at all venepuncture sites. VIP and VAS scales were used to record phlebitis and pain respectively. Upon analysis, though there was a lower VIP score in group A compared to group B （0.89 vs. 1.32）, this difference was not statistically significant （p-value = 0.277）. Furthermore, the differences in pain, as assessed by VAS, at the site of puncture and along the vein were statistically insignificant （p-value 〉 0.05）. Our results are in contradiction to few other studies which recommend a policy of routine change of carmula. Further we advocate a close and thorough monitoring of the venepuncture site and the length of vein immediately distal to the puncture site, as well as a meticulous standardized protocol for IV access.

Intravenous Fracture of a Peripheral Cannula at the Dorsum of the Hand in a Patient Who Used Walking Aids after Surgery

In orthopaedic patients, peripheral intravenous (IV) cannulation is a common procedure for various clinical purposes. This patient was introduced with a 17G cannula in the basilic vein of the dorsal venous arch of the left hand prior to knee replacement surgery. Post knee surgery patients use walking aids for mobilization. Cannula which has been placed at the dorsum of the hand has a potential to bend at the neck of the cannula when the wrist bend while holding the walking aid. Repeated bending can result in fatigue fracture of the cannula neck. In this patient at the time of cannula removal, it was noted the catheter part is broken and proximal migration. Ultrasound guided localization was done and removed with a venotomy under local anesthesia. It is advisable to place peripheral venous cannulas well away from the wrist joint, which will prevent catheter bending and fracture. This is a very important point to consider when placing cannulas in orthopaedic patients who undergo surgical procedures.

Intensive care unit adaptations in the COVID-19 pandemic:Lessons learned

The coronavirus disease 2019 pandemic had deleterious effects on the healthcare systems around the world.To increase intensive care units(ICUs)bed capacities,multiple adaptations had to be made to increase surge capacity.In this editorial,we demonstrate the changes made by an ICU of a midwest community hospital in the United States.These changes included moving patients that used to be managed in the ICU to progressive care units,such as patients requiring noninvasive ventilation and high flow nasal cannula,ST-elevation myocardial infarction patients,and post-neurosurgery patients.Additionally,newer tactics were applied to the processes of assessing oxygen supply and demand,patient care rounds,and post-ICU monitoring.

A New Technique for The Therapy of Complicated Deep Tissue Infection(with 4 Cases)

Objective: The objective of this study was to discuss the effect of double perfusion cannula accompanied with low negative pressure drainage in the treatment of complexity of abdominopelvic and perineal infections. Methods: The technology of the double perfusion cannula accompanied with low negative pressure drainage was used to treat complexity of abdominopelvic and perineal infections. Results: Double perfusion cannula accompanied with low negative pressure drainage can be applied to the treatment of complexity of abdominopelvic and perineal infections. It has an obvious effect on infection control and reduces recovery time. Conclusion: Double perfusion cannula accompanied with low negative pressure drainage has a good effect on complexity of abdominopelvic and perineal infections; it can be used in wider surgical fields to prevent infections.