Cold Crystalloid Research Articles

MicroRNA-27a Regulates Cardiomyocytic Apoptosis During Cardioplegia-Induced Cardiac Arrest by Targeting Interleukin 10–Related Pathways

In this study, experiments were designed to determine whether microRNAs (miRNAs) play a role in the regulation or modulation of cardiomyocytic reactions under cardioplegia-induced cardiac arrest during cardiopulmonary bypass. MicroRNAs play powerful and unexpected roles in numerous cardiovascular diseases. MicroRNA-based therapeutics may provide a unique opportunity to translate this knowledge into the clinical setting. Sprague-Dawley rats (10 per group) were randomly divided into three groups: control, perfusion, and arrest groups. In the perfusion group, isolated hearts were perfused with oxygenated physiologic buffered solution for 3 h using a Langendorff apparatus. In the arrest group, cold crystalloid cardioplegia solution was used to induce and maintain cardiac arrest for 1 h; hearts were reperfused for 2 h with warm oxygenated phosphate-buffered saline solution. Cardiac miRNAs and protein expression patterns were detected using miRNA arrays and two-dimensional fluorescence difference gel electrophoresis followed by matrix-assisted laser desorption/ionization-time of flight mass spectrometry. Of 103 different miRNAs and 222 different proteins expressed in the three groups, miRNA-27a was the one considered to be related to the regulation of cardiomyocyte apoptosis by targeting the interleukin 10 pathway. Transfection of H9c2 cardiomyocytes with pre-miRNA-27a, which significantly decreased the mRNA and protein levels of interleukin 10 and increased expression of nuclear factor κB and its downstream cytokines during hypoxia/reperfusion injury, could activate caspase 3 and apoptosis. Our study demonstrated the altered expression of miRNAs in cardiomyocytes during cardioplegia-induced cardiac arrest. The involvement of miRNAs in cardiomyocytic apoptosis adds another level of complexity to gene regulation, which could open up novel avenues for cardiac protection strategies during cardiac surgery.

Potassium-induced conversion of ventricular fibrillation after aortic declamping

The anti-fibrillatory effect of potassium is well recognized from experimental models. There have, however, been very few clinical reports on the use of potassium to convert ventricular fibrillation (VF) after cardioplegic arrest. In total, 8465 adult patients undergoing cardiac operations on cardiopulmonary bypass (CPB) and with cold antegrade crystalloid cardioplegic arrest were consecutively enrolled in a database. Patients with VF after removal of the aortic clamp were given 20 mmol potassium, and if needed an extra 10 mmol, in the perfusion line and the conversion rate was registered. Preoperative and intraoperative factors possibly related to the occurrence of post-ischaemic VF were assessed. Of these, 1721 (20%) patients had VF and 1366 of these (79%) were successfully treated with potassium infusion. Only 355 (21%) patients (4% of all operations) had direct-current countershock. The need for pacing was lower in the treatment group compared with the non-treatment group (P <0.001). Multivariate analysis revealed as the main findings that age, gender, amount of cardioplegia related to body mass index (BMI), and blood transfusion during the time of CPB had a highly significant (P <0.001) impact on reducing the rate of post-arrest VF. Somewhat contrary to expectation, left ventricular hypertrophy (LVH) was not a significant factor (P = 0.32) for post-arrest VF. No conversion by potassium was significant for age (P <0.001), gender (P <0.001) and LVH (P <0.001), but not for blood transfusion during CPB (P = 0.38) and for the ratio of cardioplegia-BMI (P = 0.26). The results from this register study demonstrate that potassium infusion is an effective and convenient first-hand measure to convert post declamping VF on CPB.

Adenosine instead of supranormal potassium in cardioplegia: It is safe, efficient, and reduces the incidence of postoperative atrial fibrillation. A randomized clinical trial

We aimed to evaluate the efficacy and safety of a cold crystalloid cardioplegic solution with adenosine (1.2 mmol/L) instead of supranormal potassium. Sixty low-risk patients scheduled for elective coronary artery bypass grafting (CABG) were randomized to receive standard cold crystalloid hyperkalemic cardioplegia (hyperkalemic group) or normokalemic cardioplegia in which supranormal potassium was replaced with 1.2 mmol/L adenosine (adenosine group). End points were postoperative release of troponin T and creatine kinase MB, hemodynamics measured by PiCCO arterial thermodilution catheters, perioperative release of markers of endothelial activation and injury, and clinical course. The adenosine group had a significantly shorter time to arrest than did the hyperkalemic group (mean ± standard deviation, 11 ± 5 vs 44 ± 18 seconds; P < .001). Three hearts in the adenosine group were probably not adequately drained and received additional hyperkalemic cardioplegia to maintain satisfactory cardioplegic arrest. There were no differences between groups with respect to perioperative release of markers of endothelial activation or injury and no differences between groups in postoperative release of troponin T or creatine kinase MB. Postoperative hemodynamics including cardiac index were similar between groups. The incidence of postoperative atrial fibrillation was significantly lower in the adenosine group than in the hyperkalemic group (4 vs 15; P = .01). Adenosine instead of hyperkalemia in cold crystalloid cardioplegia is safe, gives more rapid cardiac arrest, and affords similar cardioprotection and maintenance of hemodynamic parameters, together with a marked reduction in the incidence of postoperative atrial fibrillation.

Crystalloid vs. hypertonic crystalloid–colloid solutions for induction of mild therapeutic hypothermia after experimental cardiac arrest

PurposeTo compare cerebral and hemodynamic consequences of different volumes of cold acetated Ringer's solution or cold hypertonic saline dextran administered in order to achieve mild hypothermia after cardiac arrest (CA) in a pig model of experimental cardiopulmonary resuscitation (CPR). MethodsUsing an experimental pig model of 12min CA (followed by 8min CPR or no resuscitation) we compared four groups of piglets: a control group, a normothermic group and two groups with different solutions administered for induction of hypothermia. The control group of 5 piglets underwent 12min CA without subsequent CPR, after which the brain of the animals was removed immediately. After restoration of spontaneous circulation (ROSC) the resuscitated piglets were randomized into a normothermic group (NT group=10), and two hypothermic groups that received cold infusions of either 30mL/kg acetated Ringer's solution (Much fluid group, M, n=10) or 3mL/kg hypertonic saline dextran solution (Less fluid group, L, n=10), respectively, administered during 30min. Additional external cooling with ice packs was used in hypothermic groups. Sixty or 180min after ROSC the experiment was terminated. Immediately after arrest the brain was removed for histological analyses. ResultsThe median time to reach the target core temperature of 34°C after ROSC was 51.5±7.8min in L group and 48.8±8.6min in M group. Less cerebral tissue content of water (p<0.001), sodium (p<0.0001), potassium (p<0.0001) and less central venous pressure (CVP) at 5 and 15min after ROSC were demonstrated in L group. Increased brain damage was demonstrated over time in NT group (p<0.001). Less neurologic damage and BBB disruptions (albumin leakage) was observed at 180min in M group in comparison with both NT and L groups (p<0.001). ConclusionNo statistical differences were observed between the hypothermic groups in the time to achieve mild hypothermia. Although inclusion of cold hypertonic crystalloid–colloidal solutions in the early resuscitation after ROSC may be more effective than cold crystalloids in reducing brain edema, this study demonstrates that mild hypothermia induced with small volumes of cold hypertonic crystalloid–colloids is less as effective as crystalloid's induced hypothermia in mitigating brain injury after cardiac arrest.

Comparison of cold crystalloid and colloid infusions for induction of therapeutic hypothermia

While cold crystalloids have been used for induction of therapeutic hypothermia after cardiac arrest [1,2], the effectiveness of cold colloids has not so far been evaluated. Therefore, we investigated the cooling effect of rapid intravenous infusion of cold crystalloid compared to colloid in a porcine model of ventricular fibrillation (VF).

Extent II repair of thoracoabdominal aortic aneurysm secondary to chronic dissection.

Crawford extent II thoracoabdominal aortic aneurysm (TAAA) repairs generally involve replacing the full length of the thoracoabdominal aorta, from the left subclavian artery to the infrarenal abdominal aortic bifurcation, with a synthetic graft. Because of the extensive degree of aortic replacement involved, extent II repairs have been associated with the highest levels of risk for postoperative complications (1-6). To mitigate these complications, we routinely employ a multimodal approach to organ protection during these operations (7-9). To protect the spinal cord, we use mild passive hypothermia, cerebrospinal fluid drainage, left heart bypass (LHB), sequential cross-clamping, and selective reimplantation of intercostal or lumbar arteries (7,8,10,11). We intermittently deliver cold crystalloid solution to the kidneys to protect them from ischemic damage and prevent acute renal failure (12-14). We also deliver isothermic blood from the LHB circuit to the celiac axis and the superior mesenteric artery (SMA) to minimize ischemic times for the abdominal organs. To illustrate our technique for performing extent II TAAA repair, we present a video (Video 1) of such a procedure performed in a 55-year-old man with a symptomatic TAAA associated with chronic DeBakey type III aortic dissection (Figure 1). The patient had a history of hypertension, smoking, hepatitis B and C, and hepatic cirrhosis, as well as cocaine abuse, which is a risk factor for aortic dissection (15). At the time of his referral for surgical treatment, the patient was experiencing intermittent back pain. Preoperative imaging revealed a relatively normal-sized aortic arch with a dissection membrane starting just distal to the left subclavian artery. The true lumen was narrow, and the dissection extended into the celiac axis. The aneurysm measured 6 cm in diameter, and there was a large burden of thrombus in the infrarenal region. Open in a separate window Figure 1 Preoperative anatomy. Illustration and sections from a computed tomography scan showing the patient’s thoracoabdominal aortic aneurysm, which was associated with chronic aortic dissection. Note the narrow true lumen (double arrows) and the extension of the dissection into the celiac axis (single white arrow). The aneurysm begins to taper in the infrarenal region. Used with the permission of Baylor College of Medicine

Thoracoabdominal aortic aneurysm repair with a branched graft.

Many aspects of open thoracoabdominal aortic aneurysm (TAAA) repair are individualized according to patient-specific factors related to the type and extent of disease, comorbid conditions, and physiological reserve. One example of how surgeons can individualize the technical approach to this operation is the use of a prefabricated aortic graft with four side branches designed for reattaching the celiac axis, superior mesenteric artery (SMA), and both renal arteries (1-4). Using this branched graft in TAAA repairs is ideal when one of two conditions are met: (I) The patient has a connective tissue disorder (e.g., Marfan syndrome, Loeys-Dietz syndrome), and aortic tissue that remains after the procedure will be prone to aneurysmal dilatation, pseudoaneurysm formation, and rupture, eventually necessitating reintervention (5-7); or (II) the origins of the patient’s visceral vessels are far enough apart that an island patch reimplantation is not desirable. The ultimate goal of these operations is to balance the need to resect and replace as much diseased aortic tissue as possible with the need to protect the spinal cord and other organs and, thereby, prevent postoperative complications. Our strategies for organ protection have been described in detail elsewhere (8-14). To protect the spinal cord, we employ mild passive hypothermia, cerebrospinal fluid (CSF) drainage, left heart bypass (LHB), sequential cross-clamping, and selective reimplantation of intercostal or lumbar arteries (9-11,14). The renal arteries are perfused with cold crystalloid solution to protect the kidneys from ischemic damage (8,12,13). Perfusing the celiac axis and the SMA with isothermic blood from the LHB circuit minimizes the duration of abdominal-organ ischemia.

Reply to Bozok et al.

We thank Bozok and colleagues for their interest in our article [1, 2]. We would like to remind the readership that our report was a prospective randomized study of 345 consecutive AVR operations, comparing cold crystalloid cardioplegia with cold blood cardioplegia. The demographic data were similar in both groups, including the distribution of valve sizes. The main endpoint was hospital death and the secondary endpoints were low output syndrome, myocardial infarction, arrhythmias, duration of ventilatory support, stroke or minor neurological dysfunction, renal function, infections, blood transfusions and physical rehabilitation. No statistically significant differences were seen between the groups, also when comparing the patients with the longest ischaemic times. We do not think that more sophisticated tests of preoperative or postoperative myocardial dysfunction would have changed our conclusions. The absence of any differences in clinical variables or complications clearly indicated that none of the two cardioplegia techniques could be regarded as superior. In our material, there was a slight difference in the frequency of CABG as for the number of distal anastomoses (3.0 anastomoses versus 2.5 (P = 0.02) in favour of the crystalloid group). However, cardiopulmonary bypass times and crossclamp times turned out to be similar in both groups, and these intra-operative variables appear more relevant when comparing the effects of different techniques for myocardial protection.

Unusual perianesthetic malignant hyperthermia in a dog

A 7-month-old male Siberian Husky affected by lower motor neuron tetraparesis was anesthetized for electrodiagnostic testing and collection of muscle and nerve biopsy specimens. Preanesthetic physical examination revealed a high rectal temperature, and serum biochemical analysis revealed high muscle and liver enzyme activities. The dog was anesthetized twice. The dog was anesthetized with isoflurane and developed moderate hypercarbia and mild hyperthermia. Injectable anesthetic agents were used to anesthetize the dog the second time, during which the dog developed severe malignant hyperthermia. A genetic test performed after anesthesia did not reveal a mutation of the RYR1 gene, the gene that mediates calcium-release channels in skeletal muscle. On the basis of clinical features, and because other neuromuscular disorders were ruled out, a genetic channelopathy involving the skeletal muscle ion channels was suspected. The dog was disconnected from the breathing system, and active cooling of the body was performed with ice packs applied to the body surface and alcohol applied to the foot pads. Cold crystalloid solutions were administered i.v.. Intermittent positive-pressure ventilation with 100% oxygen was performed to decrease end-tidal partial pressure of carbon dioxide. Because dantrolene was not available, acepromazine was administered to facilitate a decrease in body temperature. The dog recovered from malignant hyperthermia and was discharged to the owner after 13 days of hospitalization. Dogs affected by genetic muscle disorders should be considered at risk for perianesthetic malignant hyperthermia, even in the absence of an RYR1 gene mutation.

Is remote ischaemic preconditioning of benefit to patients undergoing cardiac surgery?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether remote ischaemic preconditioning (RIPC) is of benefit to patients undergoing cardiac surgery. Altogether, more than 264 papers were found using the reported search, 16 of which represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. We conclude that RIPC is a safe protocol which could potentially be used in cardiac surgery to provide additional cardiac protection against ischaemia reperfusion injury, although it may not be appropriate for patients on K(+) ATPase channel blockers (sulphonylureas) as they seem to eliminate the effect of RIPC. In our study, we found two meta-analyses of cardiac surgery with or without RIPC. Both unequivocally showed 0.81 and 0.74 standardized mean reduction in myocardial necrosis markers in patients receiving RIPC and cardiac or vascular surgery. No difference in perioperative myocardial infarction incidence or 30-day mortality were found. In adult cardiac surgery, we found 11 randomized control trials (RCTs) ranging in size from 45 to 162 patients. Two representative studies reported no difference in postoperative cardiac troponin I concentration in RIPC vs. controls. In one of the studies (CABG ± RIPC) no additional benefit could have been observed for RIPC regarding intra-aortic balloon pump usage (controls 8.5 vs. RIPC 7.5%), inotropic support (39 vs. 50%) or vasoconstrictor usage (66 vs. 64%). On the other hand, in the other study [CABG ± AVR (aortic valve replacement) ± RIPC] significant reduction of troponin I at 8 h postoperatively (controls, 2.90 µg/l vs. RIPC, 2.54 µg/l, P = 0.043) was shown. Marked reduction in cardiac necrosis markers was also found in several smaller RCTs concerning coronary artery bypass grafting (CABG) patients receiving RIPC preoperatively: with cold crystalloid cardioplegia (44.5% reduction), with cross-clamping and fibrillation (43% reduction) and with cold blood cardioplegia (42.4% reduction). The proof of concept trials summarized here give some early evidence that RIPC may potentially provide some reduction in myocardial injury. If confirmed, in future clinical studies this technique may one day lead to a method to reduce reperfusion injury in clinical practice.

Cardiac and neurological assessment of normothermia/warm blood cardioplegia vs hypothermia/cold crystalloid cardioplegia in pediatric cardiac surgery: insight from a prospective randomized trial☆

Although normothermia and warm blood cardioplegia are widely used in adults, cold crystalloids and hypothermia remain routinely used in pediatric cardiac surgery. The superiority of either technique in both brain and myocardial protection remains controversial. We designed a prospective randomized study to compare both approaches in terms of early myocardial protection and late neurodevelopmental status. From 2004 to 2005, 47 patients were randomly assigned to either mild hypothermia associated to cold crystalloid cardioplegia (CCC, 22 patients) or normothermia with intermittent warm blood cardioplegia (IWBC, 25 patients). Intramyocyte adenosine triphosphate (ATP) was measured before, during and after cardioplegic arrest and results between groups were compared. In addition to their cardiac status, early and late neurologic assessment was performed by psychometric evaluation tests. Intracellular ATP levels were not significantly different between the two groups. However, intragroup comparison revealed different profiles according to myocardial protection: in the normothermia/warm blood cardioplegia group, ATP concentration increased during cardioplegic arrest and returned to initial values afterward (11 nmol mg(-1) vs 21 nmol mg(-1) vs 10 nmol mg(-1), p < 0.001), such changes did not occur in the cold protocol (17 nmol mg(-1) vs 19 nmol mg(-1) vs 14 nmol mg(-1), p = NS). Early neurological outcome was similar in both groups. At late follow-up (mean = 4 years), no significant difference was observed between the two groups. This study demonstrates that normothermia/IWBC protocols are not deleterious when compared with more conventional approaches. A more physiologic ATP steady state, reflecting the absence of cellular ischemic insult was observed in the IWBC group. Importantly, no significant difference was found between IWBC and CCC groups in terms of early and late neurodevelopmental status.

Abstract 254: Comparison of Cold Crystalloid and Colloid Infusions for Induction of Therapeutic Hypothermia in a Porcine Model of Cardiac Arrest

Introduction: Cold crystalloids have been used for induction of therapeutic hypothermia after cardiac arrest but so far the effectiveness of cold colloids has not been evaluated. This prospective study investigates the cooling effect of rapid intravenous infusion of cold crystalloid compared to colloid in a porcine model of ventricular fibrillation (VF). Methods: VF was electrically induced in twenty-two anesthetized domestic pigs (33 ± 2 kg). Defibrillation was attempted after 15 min CPR using the AutoPulse (Zoll Medical, USA) and artificial ventilation. After spontaneous circulation was restored, the animals were randomized to receive either 1500 mL of 1°C cold Voluven [6% hydroxyethyl starch 130/0.4 in 0.9% NaCl] within 25 min using a Zoll Power Infuser (group A; n = 9), or 1500 mL of 1°C cold normal saline (group B; n = 9), or no infusion (group C; n = 4). The animals were observed for 90 min following infusion. Cerebral, rectal, intramuscular, pulmonary artery, and subcutaneous fat body temperatures (BT) were continuously recorded using GES 130 temperature probes and GMH 3250 digital thermometers with logger function (Greisinger Electronic, Germany). Data were analyzed with JMP 3.2 software (SAS Institute, USA) and are expressed as a mean ± SD. P &lt; 0.05 was considered statistically significant. Results: 45.6 ± 2.7 mL·kg -1 of cold colloid was infused in group A, and 46.8 ± 3.1 mL·kg -1 of crystalloid in group B. The animals treated with cold fluids achieved a significant decrease of BT in all measurement sites while there was a spontaneous increase in group C. At the time of finishing infusion there was a greater decrease in cerebral and pulmonary artery temperatures in group B compared to group A (-1.7 ± 0.4 vs. -1.1 ± 0.3 °C, P &lt; 0.05, and -2.1 ± 0.3 vs. -1.6 ± 0.2 °C, P &lt; 0.05 respectively). Area under the curve (AUC) analysis of the decrease in intra-cerebral BT revealed a more vigorous cooling effect in group B compared to A (-91 ± 30 vs. -62 ± 32 °C·min, P = 0.06). There was also a higher calculated amount of absorbed heat for crystalloids compared to colloids (33.9 ± 5.7 vs. 26.6 ± 3.4 cal, P &lt; 0.05). Conclusion: Cold crystalloid infusions resulted in a more intense cooling effect than colloid infusions of the same temperature and infusion rate in this porcine model of cardiac arrest.

Three-Year Follow-up of Sirolimus-Eluting Stents vs. Bare Metal Stents for Acute Myocardial Infarction

The long-term safety and efficacy of drug-eluting stents for patients with acute myocardial infarction (AMI) remain controversial. A total of 143 consecutive patients who presented between August 2004 and July 2006 with AMI and who underwent primary percutaneous coronary intervention (PCI) using sirolimus-eluting stents (SES), were compared with a historical control cohort of 129 consecutive patients who presented between August 2002 and July 2004 and who underwent primary PCI using bare metal stents (BMS). The rate of major adverse cardiovascular events at 3 years was significantly lower in the SES group than in the BMS group (20.3% vs. 33.1%, respectively; P=0.01). This reduction was mainly driven by a decrease in the rate of target vessel revascularization (12.3% vs. 22.4%, respectively; P=0.02). There was no significant difference in the rate of cardiovascular death (4.5% vs. 5.7%, respectively; P=0.67), non-fatal myocardial infarction (4.5% vs. 9.2%, respectively; P=0.16), coronary artery bypass grafting (2.3% vs. 2.5%, respectively; P=0.93), stroke (2.4% vs. 0.8%, respectively; P=0.35), and stent thrombosis (2.9% vs. 2.3%, respectively; P=0.80) between the 2 groups. SES can be used safely and effectively in patients with AMI.

Anesthetic and Cardiopulmonary Bypass Considerations for Cardiac Surgery in Unique Pediatric Patient Populations: Sickle Cell Disease and Cold Agglutinin Disease

Physiological disturbances induced by cardiopulmonary bypass (CPB) and hypothermia during cardiac surgery are particularly pronounced in certain unique patient populations, such as patients with sickle cell disease (SCD) and cold agglutinin disease. Red blood cells containing hemoglobin S (HbS) are at increased risk of sickling under conditions encountered during cardiac surgery, leading to SCD-related complications such as vaso-occlusive events. While a target level of HbS has not been determined for patients with SCD undergoing CPB, a safe practice includes increasing the Hb level to 10 g/dL and reducing the proportion of HbS to approximately 30%. This can be accomplished through simple or exchange transfusion prior to surgery or via the modification of the CPB circuit prime. There is no clear consensus on the formulation or the delivery temperature of the cardioplegia solution necessary to prevent sickling and microvascular occlusion. The presence of cold agglutinins is another entity requiring extra vigilance for the conduct of CPB, where hypothermia can lead to activation of cold agglutinins inducing massive hemagglutination, hemolysis, microvascular thrombosis, and possibly intracoronary thrombosis. Determination of thermal amplitude is important to provide a safe reference range of temperature during surgery. High-volume plasmapheresis may be warranted to reduce cold agglutinin titers. Both warm blood cardioplegia and cold crystalloid cardioplegia above the thermal amplitude have been utilized with success.

The Myocardial Protection of Polarizing Cardioplegia Combined With Delta-Opioid Receptor Agonist in Swine

The purpose of this study was to determine whether polarized arrest using adenosine/lidocaine cold crystalloid cardioplegia in combination with the hibernation inductor δ-opioid receptor agonist pentazocine would give satisfactory myocardial protection rather than using depolarized supranormal potassium cardioplegia, supranormal potassium cardioplegia with pentazocine, or adenosine/lidocaine cardioplegia. Twenty pigs were randomly divided into four groups (n=5 each) to receive the four types of cold crystalloid cardioplegia with an aortic cross-clamp time of 1 hour. Hemodynamic data were continuously measured, as was the left ventricular end-diastolic pressure (LVEDP), left ventricular end-systolic pressure (LVESP), plus or minus derivative of change in diastolic pressure over time (±dp/dt), cardiac output, pulmonary artery pressure, pulmonary capillary wedge pressure, cardiac troponin I, and left ventricular ultrastructure. Both the adenosine/lidocaine/pentazocine group and the adenosine/lidocaine group got significantly better results than the hyperkalemic and hyperkalemic pentazocine groups in improving hemodynamic values, pulmonary capillary wedge pressure, LVEDP, LVESP, ±dp/dt, cardiac output, cardiac troponin I values, and left ventricular ultrastructure. There were no statistical differences between the adenosine/lidocaine/pentazocine group and the adenosine/lidocaine group at 1 hour after cross-clamp removal; but at 2 hours after cross-clamp removal, the adenosine/lidocaine/pentazocine group stands out (LVEDP 3.3±0.5, LVESP 122.5±18.9, +dp/dt 2.9±0.1, -dp/dt 2.0±0.6, cardiac output 2.6±0.4, and troponin I 4.9±0.5), with significant differences from the adenosine/lidocaine group (LVEDP 5.8±1.0, LVESP 98.5±10.1, +dp/dt 2.5±0.2, -dp/dt 1.0±0.2, cardiac output 2.2±0.2, troponin I 8.2±0.8; p<0.05). The defibrillation rate was largely decreased after the cross-clamp was released in the group containing pentazocine in cardioplegia. Adenosine/lidocaine/pentazocine cold crystalloid cardioplegia gave satisfactory cardiac arrest and better myocardial protection than the other three groups, especially with regard to improving prolonged postoperative cardiac function.

Novel visceral reconstruction for paravisceral aortic aneurysm complicated with aortoiliac occlusion

Visceral ischemia is a serious factor in the postoperative morbidity and mortality of suprarenal aortic reconstruction. We report a case of a patient who underwent surgical repair for a paravisceral aortic aneurysm complicated with aortoiliac occlusion, using a novel visceral reconstruction. Prior to proximal anastomosis of the aorta, we reconstructed visceral arteries by bypass grafting to the superior mesenteric artery and right renal artery (RA), using a straight 12-mm prosthetic graft originating from the intact descending aorta. During the visceral reconstruction, selective cold crystalloid perfusion of the RA was performed. We then underwent the proximal anastomosis of the aorta just below the celiac trunk using a Y-shaped prosthetic graft 18×10mm in diameter, in keeping the adequate visceral perfusion. Finally, a femoro-femoral bypass was performed with an 8-mm Gore-Tex Vascular Graft, and the left limb of the Y-shaped graft was sewn onto the side of this prosthetic graft. Postoperative computed tomography (CT) identified the successful repair of the aneurysm without any complications. Our novel visceral reconstruction could allow the surgeon to provide a physiological perfusion of visceral organs and prevent the potential visceral ischemia, during suprarenal aortic reconstruction.

Pre-hospital cooling by cold infusion—Searching for the optimal infusion regimen

Purpose of the study: The cooling efficacy of intravenous administration of cold crystalloids can be enhanced by the optimisation of the procedure. We decided to assess the temperature stability of different application regimens of cold normal saline (NS) in simulated pre-hospital conditions.

Pre-cool study reloaded: Less fluids still cool

Pre-hospital cooling of successfully resuscitated out-of-hospital cardiac arrest patients by rapid intravenous infusion of cold crystalloids has been studied repeatedly. Most often, as much as 30 ml/kg has been administered. Purpose of the study: We decided to assess a pre-hospital cooling effectivity of this cooling approach, having the target dose of 15–20 ml/kg of 4 °C cold normal saline (NS) in the setting of the physician staffed Emergency Medical Service. The impact on the clinical outcome has also been analyzed. Materials and methods: We performed an extension of prospective clinical study with a retrospective control group (PRE-COOL, Pre-hospital Cooling of Cardiac Arrest Patients). A total of 74 patients were planed to be cooled by an intravenous administration of 15–20 ml/kg of 4 °C cold NS during transport to the hospital (TH group). A total of 40 control group patients did not underwent any pre-hospital cooling attempt. Results: In the TH group, administration of 15.0 ± 5.8 ml/kg of 4 °C cold NS was followed by a pre-hospital decrease of TT of 1.5 ± 0.8 °C in 42.0 ± 19.0 min (p Conclusions: Pre-hospital induction of TH by the rapid intravenous administration of cold NS has been shown efficient even with the lower dose of coolant as was investigated in the previous studies. This approach can be associated with a potential improvement of the prognosis of the patients.

Prehospital cooling by cold infusion: searching for the optimal infusion regimen

BackgroundThe cooling efficacy of intravenous administration of cold crystalloids can be enhanced by optimisation of the procedure. This study assessed the temperature stability of different application regimens of cold normal...

Factors influencing blood transfusion requirements in robotic totally endoscopic coronary artery bypass grafting on the arrested heart

Robotic technology enables totally endoscopic coronary artery bypass grafting (TECAB) procedures. These operations can be performed on either the beating or arrested heart. One challenge of the latter version is a potentially increased need for blood transfusions. We investigated factors associated with transfusion requirements in totally endoscopic coronary artery bypass on the arrested heart (AH-TECAB). A total of 161 patients, 124 males and 37 females, aged 59 (31-77 years) years, with European System for Cardiac Operative Risk Evaluation (EuroSCORE) 1 (0-7) underwent AH-TECAB using the daVinci telemanipulation system. The Heartport/Cardiovations™ or ESTECH-RAP™ systems were applied for remote access perfusion and aortic endoocclusion. In all cases, the operation was carried out in moderate hypothermia and cardiac arrest using cold crystalloid cardioplegia mixed with blood. After 20 cases, the blood-transfusion rate dropped from 69% to 44%. The overall median number of transfusions was 1 (0-21). The following pre- and intra-operative factors showed a strong association with the application of packed red blood cells (PRBCs): preoperative haemoglobin level (p < 0.001), female gender (p < 0.001), shorter height (p < 0.001), lower weight (p < 0.001), long operative time (p < 0.001) and long cardiopulmonary bypass time (p = 0.001), intra-operative surgical problem (p < 0.001) and conversion to a larger thoracic incision (p < 0.001). Postoperatively, patients with longer ventilation time (p < 0.001) and those needing revision for bleeding (p < 0.001) also received significantly more PRBCs. We conclude that multiple factors are associated with increased blood transfusion requirements in AH-TECAB. However, the transfusion rate can be reduced with experience. Identification of these factors may help in avoiding the application of blood products in the next generation of AH-TECAB procedures.