"Extracorporeal Membrane Oxygenation for Greater Poland" Program: How to Save Lives and Develop Organ Donation?

The "ECMO for Greater Poland" program takes full advantage of the extracorporeal membrane oxygenation (ECMO) perfusion therapy opportunities to promote the health of the 3.5 million inhabitants in the region. The main implementation areas are treatment of patients with hypothermia; severe reversible respiratory failure (RRF); critical states resulting in heart failure, that is, cardiac arrest, cardiogenic shock, or acute intoxication; and promotion of the donor after circulatory death (DCD) strategy in selected organ donor cases, after unsuccessful life-saving treatment, to achieve organ recovery. This organizational model is complex and expensive, so we used advanced high-fidelity medical simulation tests to prepare for real-life experience. Over the course of 4 months we performed scenarios including "ECMO for DCD," "ECMO for extended cardiopulmonary resuscitation," "ECMO for RRF," and "ECMO in hypothermia." Soon after these simulations, Maastricht category II DCD procedures were performed involving real patients and resulting in 2 successful double kidney transplantations for the first time in Poland. One month later we treated 2 hypothermia patients (7 adult patients with heart failure and 5 patients with reversible respiratory failure) with ECMO for the first time in the region. Fortunately, we have discovered an important new role of medical simulation. It can be used not only for skills testing but also as a tool to create non-existing procedures and unavailable algorithms. The result of these program activities will promote the care and treatment of patients in critical condition with ECMO therapy as well as increase the potential organ pool from DCDs in the Greater Poland region of Poland.

Novel Method of Infection Prophylaxis in Heart Transplantation by Retrosternal Gentamycin Sponge Application.

BACKGROUND: Surgical wound infections are more frequent in patients undergoing heart transplantation than in other heart surgery patients. There is a wide spread of sternal wound infection incidence in transplant patients ranging from 4% to 40%. It is first study describing local gentamicin sponge application during heart transplantation procedure. MATERIALS AND METHODS: We enrolled 75 patients in a retrospective, single-center study, including 25 patients who underwent orthotopic heart transplantation (heart transplant group) and 50 in the cardiac surgery group. They were in mean age of 49 ± 12 years and 51 ± 13 years in heart transplantation and cardiac surgery group, respectively. A gentamicin sponge was inserted intraoperatively between sternal borders before chest closure in all heart transplantation patients. RESULTS: There was 1 early death (4%) on postoperative day 7 owing to Clostridium difficile infection in the heart transplant group. There was 1 death (2%) in the cardiac surgery group owing to multiorgan failure secondary to perioperative heart ischemia. There was neither bacterial sternal wound infection nor sternal instability in the heart transplant group. None of the patients who had gentamicin sponge applied had wound healing problems. Two patients (4%) had a deep sternal wound infection in the cardiac surgery group, who had no sponge application; 1 (2%) was treated by surgical debridement and active drainage and 1 (2%) by vacuum therapy. There were 11 patients (44%) discharged on insulin therapy in the heart transplant group and 21 (21%) in the cardiac surgery group. Mean overall postoperative hospital stay was 35 ± 19 days in the heart transplant group and 10 ± 4 days in the cardiac surgery group. CONCLUSIONS: Gentamicin sponge is an effective local infection prophylaxis in heart transplant patients.

Air entrainment during high-frequency jet ventilation in a model of upper tracheal stenosis.

BACKGROUND: Previous work has demonstrated that when high-frequency jet ventilation (HFJV) is applied above an airway stenosis, higher distal airway pressures are produced compared with when the same ventilation is delivered below the stenosis (BSV). This study aimed to investigate the mechanisms underlying this finding. METHODS: HFJV was applied to a model of laryngo-tracheal stenosis with the jet located above the stenosis (ASV), with a catheter passed through the stenosis (TSV) or with HFJV delivered by a side port BSV. For each configuration and over a range of diameters of stenosis (2.5-8.5 mm), distal tracheal pressures and delivered minute volume were measured and air entrainment estimated. Experiments were repeated using the same model with the addition of a simulated 'pharynx' around the stenosis. RESULTS: Distal airway pressures, minute volumes, and air entrainment were consistently higher during ASV compared with BSV and TSV. The presence of the 'pharynx' made no significant difference to airway pressures or air entrainment. Delivered minute volumes varied between ASV, TSV, and BSV, and were also dependent on the stenosis diameter. With ASV, there appeared to be a range of stenosis diameters (4.0-5.5 mm) which 'maximized' minute volumes. CONCLUSIONS: The results suggest that the high airway pressures generated during ASV are the consequence of air entrainment and this effect, although reduced slightly, is maintained in the presence of the model pharynx. In contrast to the previous work, no significant entrainment occurred during BSV. If applicable to patients, these data suggest that ASV HFJV should be avoided in small diameter stenoses, but provides more efficient gas delivery and greater distending pressures with larger stenoses. BSV HFJV produces lower distal pressures and more consistent oxygen concentrations of injected gas across a range of stenosis diameters.

Effects of helium on high frequency jet ventilation in model of airway stenosis.

BACKGROUND: The addition of helium to the inspired gas may facilitate ventilation in the presence of clinically evident upper airway obstruction. However, there are no data on the effects of using a helium-oxygen mixture during high frequency jet ventilation (HFJV) in upper airway obstruction. METHODS: HFJV at a frequency of 150 min(-1) (driving pressure 2 bar, inspiratory time 30%) was applied to a trachea-lung model to simulate ventilation through varying degrees of fixed laryngotracheal stenosis (2.5-8.5 mm). HFJV was delivered from above, through and below the level of stenosis to simulate supraglottic, transglottic and infraglottic administration. Measurements of distal tracheal pressures were repeated for each route at steady state for each stenosis diameter using both 100% oxygen and helium-oxygen (50% oxygen, 50% helium). The output of the ventilator was measured during operation on oxygen and helium-oxygen. RESULTS: Peak, mean and end-expiratory pressures were greater during simulated supraglottic HFJV than during transglottic and infraglottic HFJV, and pressures increased markedly as the diameter of the stenosis decreased for all routes of ventilation (P<0.001). Generated pressures during HFJV using helium-oxygen and 100% oxygen were very similar overall, although reductions in pressures were observed during ventilation with helium-oxygen via the transglottic and transtracheal routes at stenosis diameters <4 mm (P<0.05). However, HFJV with the helium-oxygen mixture increased the delivered gas volumes by approximately 18%. CONCLUSIONS: Using 50% helium-oxygen during HFJV in the presence of airway stenosis allows an 18% increase in minute volume at generated airway pressures which are the same as or lower than those when using 100% oxygen.

Immunocytochemical study on endothelial integrity of saphenous vein grafts harvested by minimally invasive surgery with the use of vascular mayo stripers. A randomized controlled trial.

OBJECTIVES: The aim of this study is to compare the endothelial integrity of saphenous vein grafts harvested by minimally invasive surgery and veins harvested conventionally for coronary artery bypass surgery in 200 participants who were assigned to interventions by using random allocation. DESIGN: Randomized controlled trial. Methods. Immunocytochemistry with anti-CD 31 antibodies and anti-nitric oxide synthase (NOS) antibodies were employed to identify the endothelial integrity. RESULTS: The CD 31 immunostaining showed that the endothelial cell integrity of the minimally invasive harvested veins was preserved in 82+/-13% of the circumference of luminal endothelium, while in conventionally harvested grafts it was reduced to 64+/-15% (p=0.05).> This was associated with the lack of CD 31 expression in vasa vasorum (10 and 18%) in both groups, respectively, (p=0.02). The NOS immunostaining revealed that the endothelial integrity of the minimally invasive harvested grafts was preserved in 96+/-4% of the luminal endothelium circumference as compared to 74+/-10% in conventionally harvested grafts (p=0.05). The percentage of cases with the lack of NOS expression in all vasa vasorum was 12 and 21%, in G1 and G2, respectively, (p=0.02). CONCLUSION: The endothelial integrity of saphenous vein grafts harvested by minimally invasive surgery is better preserved than with the grafts obtained by the conventional manner. This could play an important role in improving vein graft patency rates.

Evaluation of pre-emptive intramuscular phenylephrine and ephedrine for reduction of spinal anaesthesia-induced hypotension during Caesarean section.

Pre-emptive intramuscular (i.m.) vasopressors were evaluated in 108 patients undergoing elective Caesarean section under spinal anaesthesia, assigned to four groups in a randomized, double-blind, placebo-controlled study. Group 1 received pre-emptive phenylephrine 4 mg i.m., group 2 received phenylephrine 2 mg i.m., group 3 received ephedrine 45 mg i.m., while controls received an i.m. injection of saline, all given immediately after induction of spinal anaesthesia. Hypotension was defined as a 25% decrease in mean arterial pressure (MAP). Rescue intravenous (i.v.) boluses of ephedrine were given if the patient was hypotensive or reported nausea, vomiting or dizziness. The incidence of hypotension was 33% in the phenylephrine 4 mg group compared with 70% in the control and phenylephrine 2 mg groups (P=0.03), and 48% in the ephedrine 45 mg group. The phenylephrine 4 mg and ephedrine 45 mg groups had a significantly lower percentage reduction in MAP (-21 (SD 14)% and -22 (14)%) compared with controls (-32 (18)%, P=0.04). They also had a lower total dose of rescue i.v. ephedrine (15.7 (15.7) mg and 15.8 (15.6) mg) compared with controls (28.8 (20.6) mg, P=0.02). We conclude that pre-emptive i.m. phenylephrine 4 mg and ephedrine 45 mg reduce the severity of hypotension and the total dose of rescue i.v. ephedrine during spinal anaesthesia for Caesarean section.

Do patients over 40 years of age benefit from surgical closure of atrial septal defects?

OBJECTIVE: To determine the value of surgical closure of atrial septal defects in patients over 40 years of age. METHODS: Retrospective analysis of 76 patients (63 women, 13 men), age range 40-62 years (mean (SD) 45.8 (5.1) years), who underwent surgical repair of atrial septal defect. Pre- and postoperative clinical status (New York Heart Association (NYHA) functional class) was assessed, and ECG, x ray, and echocardiographic investigations performed. Follow up was between 1 and 17 years. RESULTS: One operative and one late death occurred during the study period. Before operation, 47 patients (61.8%) were in NYHA functional classes III and IV. After operation, 61 patients (82.4%) were in classes I and II. Four patients had atrial fibrillation before surgery versus nine after surgery. Before operation, 52 patients had intensified pulmonary vascularity compared with only seven after operation. Echocardiographic examination showed a significant reduction in right ventricular dimension (4.10 (0.91) v 2.95 (0.36) cm, p < 0.001). No residual intracardiac shunts were identified on echocardiographic follow up. CONCLUSIONS: Surgical closure of atrial septal defects in patients over 40 years old can improve their clinical status and prevent right ventricular dilatation and insufficiency.

Mitral valvuloplasty with sutures used for aortic prosthesis implantation.

BACKGROUND: The purpose of this study was to analyze surgical treatment for aortic valve lesions with coexisting mitral regurgitation (MR). METHODS: Seventy-five patients were divided into two groups according to intensity of MR (group 1, MR less than or equal to II; group 2, MR greater than or equal to II/III). There were two control groups (control 1, only patients with implantation of aortic valve; control 2, patients with implantation of both aortic and mitral prostheses). During implantation of a mechanical aortic prosthesis, the same suture for fixation of a mechanical prosthesis and for suspension of mitral commissural regions and lifting the base of anterior mitral cusp was used. RESULTS: In all patients, no early death occurred. There were two late deaths, one due to endocarditis, and the other to heart failure. All patients from both groups had decreased MR. Selected echocardiographic parameters improved: end diastolic and end systolic diameter and ejection fraction in group 2 improved in proportion to patients in whom mitral valves were implanted (control 2). CONCLUSIONS: Simultaneous suspension of the mitral commissure area during mechanical aortic prosthesis implantation reduces associated MR. This technique seems to be efficient during implantation of aortic prostheses in patients with coexisting MR.

A new combined spinal-epidural apparatus: measurement of the distance to the epidural and subarachnoid spaces.

A new combined spinal-epidural anaesthesia apparatus with a 27G lockable spinal needle was used in 151 patients. Two groups could be created, based on whether dural perforation was felt or not (group 1: with dural click; group 2: no dural click). Measurements of the epidural space depth and of the protrusion of the spinal needle from the epidural needle (tip-to-tip distance) were made. The mean depth of the epidural space was 5.59 cm. Correlations were found with body weight, weight-to-height ratio and body mass index (p < 0.001). The mean tip-to-tip distance measured was 7.0 mm in the patients of group 1, whereas in group 2 a distance of 8.9 mm was found. This difference was statistically significant. Correlations were found between the epidural space width and the patient's height, weight-to-height ratio and body mass index. Four patients felt paraesthesia during placement of the spinal needle and, in another four patients, aspiration was necessary to detect cerebrospinal fluid. Two patients needed epidural top-ups due to insufficient level of anaesthesia. The lockable spinal needle provides safe and stable conditions during injection and a high rate of success in reaching the subarachnoid space.