Acute limb ischemia in a COVID-19 patient.

Introduction: Acute limb ischemia (ALI) is defined as an abrupt decrease in arterial perfusion of a limb with a threat to viability of the limb. Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2, and has been declared as a global pandemic by the World Health Organization. Patients with COVID-19 have deranged blood coagulation parameters and are prone to thromboembolic events. This hypercoagulable state caused by COVID-19 mainly manifests as venous thromboembolism. Peripheral arterial involvement is less frequent. We present a case of a spontaneous ALI in a COVID-19 patient. Case: A 62-year-old man with an insignificant past medical history presented with ALI 12 days after an initial diagnosis of COVID-19. He was on therapeutic doses of low molecular weight heparin when ischemic symptoms developed. A surgical thrombectomy was unsuccessful. He partially benefited from intravenous unfractionated heparin and iloprost infusions. He was discharged home on postoperative day 14, and is scheduled to have an amputation of the 1st toe. Conclusions: COVID-19 infection is associated with an increased incidence of thromboembolic events, including ALI. Even young and otherwise healthy patients may develop ALI despite the use of prophylactic anticoagulation. Management of ALI in COVID-19 patients might be harder than expected, due to the hypercoagulable state. Patients may benefit from prolonged postoperative unfractionated heparin administration.

Correction of dilutional anemia induces renal dysfunction in diabetic patients undergoing coronary artery bypass grafting: a consequence of microcirculatory alterations?

BACKGROUND: In this study we aimed to evaluate the effects of dilutional anemia resulting from cardiopulmonary bypass (CPB) and its correction with red blood cell (RBC) transfusion on tissue oxygenation and renal function in diabetic patients undergoing coronary artery bypass grafting (CABG). METHOD: 70 diabetic patients who underwent elective CABG and whose hematocrit values had been between 24-28% at any time during CBP were prospectively randomized and equally allocated to two groups: patients who received RBC during CPB (group I, n = 35) vs. did not receive RBC during CPB (group II, n = 35). Besides routine hemodynamic and biochemical parameters, biomarkers of ischemia and renal injury such as ischemia modified albumin (IMA), protein oxidation parameters [advanced oxidative protein products (AOPP), total thiol (T-SH)], neutrophil gelatinase-associated lipocalin (NGAL) and estimated glomerular filtration rate (eGFR) were measured in both groups. RESULTS: In group I, T-SH, NGAL and urea levels were found to be significantly increased postoperatively compared to preoperative measurements (p < 0.05). Also, postoperatively, NGAL, creatinine, aspartate aminotransferase and AOPP levels were higher in group I than group II (p < 0.05). CONCLUSION: The correction of anemia with RBC transfusion in diabetic patients undergoing CABG could increase the risk of renal injury. Further studies verifying the effects of blood transfusions at the microcirculatory level are needed to optimize the efficacy of transfusions.

Hybrid synchronous treatment of two separate cardiovascular pathologies: Coronary artery bypass grafting and endovascular aortic replacement.

Coronary artery disease and abdominal aortic aneurysm may frequently be together, particularly in elderly patients. Treatment strategies should be tailored according to the needs and specific properties of each patient. Hybrid synchronous procedures may be a choice of therapy in these patients, as well as staged procedures. Herein, we present the first hybrid synchronous case of Turkey to treat two separate cardiovascular pathologies.

Is the Nexfin finger cuff method for cardiac output measurement reliableduring coronary artery bypass grafting? A prospective comparison with the echocardiography and FloTrac/Vigileo methods.

BACKGROUND/AIM: The aim of the current study was to assess the accuracy of cardiac output (CO) measurements obtained by the Nexfin finger cuff method as compared with the FloTrac/Vigileo and echocardiography methods in coronary artery bypass grafting (CABG) patients. MATERIALS AND METHODS: First-time elective CABG patients were prospectively enrolled in this study and divided into three groups according to CO measurement method. CO measurements were performed simultaneously by three different contributors and were collected by the fourth one 24 h postoperative in the intensive care unit (ICU). Data were statistically analyzed. RESULTS: Seventeen female and 13 male patients between 42 and 78 years of age (with a mean of 56 ± 4) were the subjects of this study. The mean CO measurements were 5.9 ± 1.4 L/min, 5.8 ± 1.1 L/min, and 6.0 ± 1.1 L/min for the Nexfin, FloTrac/Vigileo, and echocardiography methods, respectively (P > 0.05). The correlation values between Nexfin and FloTrac/Vigileo, Nexfin and echocardiography, and FloTrac/Vigileo and echocardiography were r = 0.445, r = 0.377, and r = 0.384, respectively (P < 0.05). CONCLUSION: Nexfin yielded results comparable to those obtained with FloTrac/Vigileo and echocardiography for the postoperative CO assessment of CABG patients. Nexfin may be used in uncomplicated, hemodynamically stable patients in ICU as a reliable and totally noninvasive method of CO measurement.

Transradial catheterization may decrease the radial artery luminal diameter and impair the vasodilatation response in the access site at late term: an observational study.

The present study aimed to evaluate the late-term changes in radial artery luminal diameter (RAD) and vasodilatation response following transradial catheterization (TRC). TRC-inducing trauma to radial artery intima may trigger chronic phase vascular changes and lead to anatomical and functional impairment. There is controversial data whether the impairment persists or repairs later. Fifty-six consecutive patients undergoing TRC were enrolled prospectively. Baseline RAD, flow-mediated dilatation (FMD) and nitroglycerin-mediated dilatation (NMD) of the radial artery at the access site were measured before TRC by high-resolution ultrasound. Six months later; RAD, FMD and NMD were measured again at the same access site. RAD at the sixth month was reduced compared with pre-procedural measurements (2.85 ± 0.44 versus 2.74 ± 0.42 mm, p = 0.0001).The average FMD decreased to 5.66 ± 5.87 %, which was significantly lower than the observed pre-procedural FMD (9.45 ± 5.01 %) 6 months after TRC (p = 0.0001). Likewise, the average NMD at the sixth month was reduced compared with pre-procedural NMD (9.52 ± 6.77 versus 6.64 ± 6.51 %, p = 0.018). Logistic regression analysis indicated that pre-procedural radial artery diameter to sheath size ratio was the independent predictor of NMD reduction (95 % confidence interval, ß = -9.74, p = 0.024). TRC may lead to a significant luminal diameter reduction and impairment of vasodilatation response in the radial artery at late term.

Mirror Image Gerbode or Partial Atrioventricular Canal Defect?

Gebode defect, that can accurately be treated surgical repair, is defined as a true communication between left ventricle and right atrium. A 74-year-old woman with a worsening history of ortophnea and peripheral edema was hospitalised. A communication between right atrium and left ventricle was diagnosed using transeusophageal echocardiography. The defect was repaired and mitral valve was replaced with a biologic valve. It would be beter to tailor surgical strategy for each case with atrioventricular canal defect after preoperative transeusophageal echocardiography and peroperative direct sight.

Comparative effects of hemodilutional anemia and transfusion during cardiopulmonary bypass on acute kidney injury: a prospective randomized study.

AIM: Acute kidney injury after cardiopulmonary bypass has been associated with dilutional anemia during surgery. We aimed both to explore if this relation is modulated by blood transfusion and to understand the postoperative contribution of protein oxidation. METHODS: In this randomized prospective study, after ethics committee approval and informed consent, 30 patients undergoing first-time elective coronary artery bypass grafting (CABG) with hematocrit between 21% and 25% at any time during extracorporeal circulation (ECC) were randomly and equally allocated into two groups. Group I consisted of patients who received red blood cells (RBC) during ECC, while in Group II, patients did not receive any RBCs. Besides routine hemodynamic and biochemical parameters, markers of renal injury such as neutrophil gelatinase-associated lipocalin (NGAL), creatinine clearance, and protein oxidation parameters (advanced oxidative protein products [AOPP], total thiol [T-SH]) were determined in both groups. RESULTS: (1) Both cardiovascular parameters (MAP, HR) and the hospitalization period of the transfused group were not significantly different compared to the non-transfused group (P > .05); (2) While urine NGAL level (P < .05) increased and GFR (P < .01) decreased in the transfused group compared to the preoperative period, there were no significant changes in respective parameters of the non-transfused group compared to preoperative period; (3) AOPP concentrations did not change compared to postoperative periods in both groups (P > .05). However, T-SH concentration showed a transient increased at postoperative hour 6 (P < .001 vs preoperative period) but normalized at postoperative hour 24 (P > .05 versus preoperative period). CONCLUSION: These findings suggest that a hematocrit value over 21% during ECC is safe for renal functions. RBC transfusion just to increase hematocrit may be deleterious.

Oxygen fraction adjustment according to body surface area during extracorporeal circulation.

BACKGROUND: The inspiratory oxygen fraction (FiO2) is usually set between 60% and 100% during conventional extracorporeal circulation (ECC). However, this strategy causes partial oxygen pressure (PaO2) to reach hyperoxemic levels (>180 mmHg). During anesthetic management of cardiothoracic surgery it is important to keep PaO2 levels between 80-180 mmHg. The aim of this study was to assess whether adjusting FiO2 levels in accordance with body temperature and body surface area (BSA) during ECC is an effective method for maintaining normoxemic PaO2 during cardiac surgery. METHODS: After approval from the Ethics Committee of the University of Acibadem, informed consent was given from 60 patients. FiO2 adjustment strategies applied to the patients in the groups were as follows: FiO2 levels were set as 0.21 × BSA during hypothermia and 0.21 × BSA + 10 during rewarming in Group I; 0.18 × BSA during hypothermia and 0.18 × BSA + 15 during rewarming in Group II; and 0.18 × BSA during hypothermia and variable with body temperature during rewarming in Group III. Arterial blood gas values and hemodynamic parameters were recorded before ECC (T1); at the 10th minute of cross clamp (T2); when the esophageal temperature (OT) reached 34°C (T3); when OT reached 36°C (T4); and just before the cessation of ECC (T5). RESULTS: Mean PaO2 was significantly higher in Group I than in Group II at T2 and T3 (P = .0001 and P = .0001, respectively); in Group I than in Group III at T1 (P = .02); and in Group II than in Group III at T2, T3, and T4 (P = .0001 for all).  CONCLUSION: Adjustment of FiO2 according to BSA rather than keeping it at a constant level is more appropriate for keeping PaO2 between safe level limits. However, since oxygen consumption of cells vary with body temperature, it would be appropriate to set FiO2 levels in concordance with the body temperature in the rewarming period.

Utility of cerebral oxymetry for assessing cerebral arteriolar carbon dioxide reactivity during cardiopulmonary bypass.

BACKGROUND: Our study evaluated changes in cerebral arterial oxygen saturation (rSO2) during cardiopulmonary bypass (CPB) that were caused by changes in arterial carbon dioxide tension (PaCO2). METHODS: A group of 126 patients undergoing routine, elective, first-time coronary artery bypass graft surgery (CABG) was entered into a prospective study using bilateral near-infrared spectroscopy (NIRS) before anesthetic induction (T1), after anesthetic induction (T2), and continuing at 5-minute intervals during moderate hypothermic (32°C) CPB. Pump flows were set at 2.5 L/min/m(2) and adjusted to maintain mean arterial pressure (MAP) within 10 mmHg of the MAP recorded at the initial fifth minute of CPB (T3). Thirty-two patients were excluded from data collection because MAP could not be stabilized within the target range of 60-90 mmHg. In the remaining 94 patients, after obtaining steady state flow, MAP, and oxygenation, a trial period of hypocarbia (mean PaCO2 of 30 mmHg) was induced by increasing oxygenator fresh gas flow rate (FGFR) to 2.5 L/min/m(2) (T4). A reciprocal period was then measured at reduced FGFR (0.75 L/min/m(2)) (T5). RESULTS: After 20 minutes of a higher (2.75 L/min/m(2)) (FGFR), mean PaCO2 decreased from a baseline of 38 ± 4 mmHg to 30 ± 2 mmHg. This was associated with a parallel decrease (-10 ± 9%) in mixed cerebral oxygen saturation without alteration of mean arterial oxygen tension (PaO2), lactate, MAP, CPB flow, or other parameters implying increased cerebral oxygen extraction. CONCLUSION: Parallel changes in PaCO2 and rSO2 occur during CPB when other variables remain constant, and are due to the effects of carbon dioxide on cerebral arterioles. Cerebral oxygen saturation measured by NIRS may be a useful indirect measure of PaCO2 when continuous blood gas analysis is not possible during open-heart surgery. Cerebral oximetry values may be useful measurements for setting an optimum gas flow rate through the oxygenator.

Use of bone wax is related to increased postoperative sternal dehiscence.

AIM: To investigate the relation between use of bone wax and postoperative sternal dehiscence after cardiac surgery. MATERIAL AND METHODS: Five thousnad three hundred and eighteen consecutive patients who underwent cardiac surgery between 1999 and 2009 were evaluated prospectively. Perioperative use of bone wax, perioperative data and outcome parameters were recorded. Multivariate logistic regression analysis was performed to define independent risk factors for postoperative sternal dehiscence. RESULTS: Bone wax was used in a total of 1151 (21%) patients. Postoperative sternal dehiscence was detected in 88 (1.6%) patients. The postoperative sternal dehiscence rate was 1.4% in patients without bone wax and 2.5% in patients with bone wax (p = 0.001). The rate of bone wax use was 36.4% in patients with sternal dehiscence and 21.4% in patients without sternal dehiscence (p < 0.001). Independent risk factors for postoperative sternal dehiscence were defined as: age > 70 (OR = 1.9, 95% CI: 1.2-3.1, p = 0.005), chronic obstructive lung disease (OR = 2.4, 95% CI: 1.5-3.9, p < 0.001), use of bone wax (OR = 1.6, 95% CI: 1.03-2.5, p = 0.03), nonelective operation (OR = 2, 95% CI: 1.1-3.4, p = 0.009), and body mass index > 30 (OR = 2.2, 95% CI: 1.4-3.5, p < 0.001). CONCLUSIONS: Our findings suggest that use of bone wax may be associated with increased postoperative sternal dehiscence after cardiac surgery. Thus liberal use of bone wax should be restricted.

A hybrid therapy as a third approach for type 1 proximal endoleak of thoracic endovascular aortic replacement: Caroticocarotid bypass and re-redo endovascular therapy.

INTRODUCTION: In selected cases with thoracic aortic aneurysm (TAA), thoracic endovascular aortic replacement (TEVAR) is commonly used and shall be proper therapy method. We are presenting a case of TAA previously treated twice by endovascular aortic approaches and complicated by type 1 endoleak. CASE: A 67-year-old male patient was admitted to our clinic with back pain at rest. He underwent TEVAR five years ago, twice in 6 month. With contrasted computed tomography of chest and abdomen, a new type 1 proximal endoleak was diagnosed, and after routine preoperative follow up, the patient was operated on. At the same session right to left caroticocarotid bypass and re-redo TEVAR were performed. The new endovascular graft was placed as the proximal landing zone to be set between left carotid artery and brachiocephalic truncus. The patient was discharged on postoperative day 4 without any problems. CONCLUSION: As new techniques and methods have been developed, mortality rates have decreased to 2-3% but in older and high risk patients, mortality rates still remain high [1]. TEVAR is a safe and effective treatment method in the proper and selected patients with thoracic artery aneurysm [2]. Moreover, TEVAR can also be performed as a part of hybrid procedures for arcus aortic aneurysms [3]. But it should be kept in mind that late secondary intervention rates are higher in TEVAR.

Recurrent cardiac metastasis of primary femoral osteosarcoma: a case report.

A 17-year-old female patient with a history of surgery for primary femoral and metastatic lung osteosarcoma was admitted to our clinic with palpitations. Upon evaluation, a metastatic osteosarcoma in the left ventricle was diagnosed. Based on the collaborative decision of the oncology and cardiovascular surgery clinics, surgery was performed and the patient was discharged without any problems. According to the recommendation of the oncology clinic, chemotherapy was postponed for 6 months after surgery. Five months postoperatively, however, she had a recurrence with 2 tumors. Based on the collaborative decision, chemotherapy was initiated and in 2 months the size of the recurrent tumors had diminished. The patient is still under the care of the oncology and cardiovascular surgery clinics and continuing her chemotherapy regimen. Osteosarcomas have a high mortality. Metastatic tumors of the heart are not common. The location of the metastasis and the characteristics of the primary tumor determine the treatment modality. In some previously published reports, various treatment choices have been described. In the present case report, we present a rare case with metastatic cardiac osteosarcoma.

Traumatic aneurysm in persistent sciatic artery.

A 59-year-old male patient admitted to our hospital with a pulsatile right gluteal mass with history of formation after blunt trauma. Persistent sciatic artery and its traumatic aneurysm was diagnosed after medical examination followed by peripheric digital substraction angiography. Surgery was performed under general anesthesia, and the patient was discharged from the hospital on postoperative day 7 without any problems. The sciatic artery, a continuation of the internal iliac artery into the popliteal-tibial vessels, represents the major blood supply to the lower limb in early embryologic development. Its persistence is very rare, and the aneurysmatic dilatation is the most common pathology diagnosed. Here, we present a rare case of persistent sciatic artery presenting with a traumatic aneurysm treated by iliopopliteal bypass surgery and ligation of the internal iliac artery proximal to the aneurysm.