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PubMed1987

Estimation of endogenous glucose production during hyperinsulinemic-euglycemic glucose clamps. Comparison of unlabeled and labeled exogenous glucose infusates.

Tracer methodology has been applied extensively to the estimation of endogenous glucose production (Ra) during euglycemic glucose clamps. The accuracy of this approach has been questioned due to the observation of significantly negative estimates for Ra when insulin levels are high. We performed hyperinsulinemic (300 microU/ml)-euglycemic glucose clamps for 180 min in normal dogs and compared the standard approach, an unlabeled exogenous glucose infusate (cold GINF protocol, n = 12), to a new approach in which a tracer (D-[3-3H]glucose) was added to the exogenous glucose used for clamping (hot GINF protocol, n = 10). Plasma glucose, insulin and glucagon concentrations, and glucose infusion rates were similar for the two protocols. Plasma glucose specific activity was 20 +/- 1% of basal (at 120-180 min) in the cold GINF studies, and 44 +/- 3 to 187 +/- 5% of basal in the hot GINF studies. With the one-compartment, fixed pool volume model of Steele, Ra for the cold GINF studies was -2.4 +/- 0.7 mg X min-1 X kg-1 at 25 min and remained significantly negative until 110 min (P less than .05). For the hot GINF studies, Ra was never significantly less than zero (P greater than .05) and was greater than in the cold GINF studies at 20-90 min (P less than .05). There was substantially less between-(78%) and within- (40%) experiment variation for the hot GINF studies compared with the cold GINF studies. An alternate approach (regression method) to the application of the one-compartment model, which allows for a variable and estimable effective distribution volume, yielded Ra estimates that were suppressed 60-100% from basal. In conclusion, the one-compartment, fixed pool volume model of glucose kinetics is inadequate for the estimation of Ra during euglycemic glucose clamps. Two new strategies for estimating Ra from the one-compartment model, the hot GINF protocol and the regression method calculation, yielded more accurate and physiologically plausible estimates of Ra than currently used methodology.

Animals↗
PubMed1976

The effect of temporary clamping of the renal vessels on the vascular resistance in rabbit kidneys.

In studies of 45 rabbits, either the renal artery (35 animals), or the renal artery and vein (10 animals) were clamped in situ. The effect of the clamping--of the warm ischemia--on the vascular resistance of the kidney after reestablishment of the circulation was examined in perfusion studies made after removal of the kidneys from groups of 5 animals between 1 and 5 days after revascularization. Resistance patterns were measured during hypothermic perfusion. The results confirm earlier findings that vascular resistance increases in proportion to the duration of warm ischemia up to 60 min, but not thereafter. The renal vascular resistance falls over the days following revascularization, more slowly after longer periods of ischemia. Thus after 60 min of warm ischemia the vascular resistance became normal within 24 hours, but after 180 min of warm ischemia, the normal resistance range was not reached until 96 hours after reestablishment of the circulation. When both the renal artery and the renal vein were clamped, the pattern was the same but much less emphatic. The vascular resistance never attained such high values as seen after clamping of the renal artery alone, and became normal after 24 hours of revascularization, even when the period of warm ischemia was as long as 180 min.

Animals↗
PubMedDate not supplied

Animal model for investigation of spinal cord injury caused by aortic cross-clamping.

The objective of this experimental protocol was to design a large animal model that could simulate the ischemic condition caused by aortic cross-clamping during the operation for intrathoracic and thoraco-abdominal aneurysm. Domestic swine weighing 25 to 30 kg were used for this model. The thoracic cavity was opened through the fourth intercostal space. Cross-clamp was applied below the left subclavian artery. Duration of cross-clamp was 30 min and the reperfusion period was 24 h. Methods of assessment included Tarlov's criteria, histology transmission electron microscopy, and spinal cord perfusion with microspheres. This model is reproducible. The results of experimental protocols completed using this model are referenced. This article discusses the details of the experimental protocol with steps toward reproduction of the model and rationalization. This animal model can be used for the evaluation of the pathophysiology of spinal cord injury and sensory- and motor-evoked potentials, and most importantly it can also be used for the examination of pharmacological interventions for prevention and treatment of ischemia reperfusion injury caused by aortic cross-clamping.

Animals↗
PubMed1996

Clamped Corticosterone (B) Reveals the Effect of Endogenous B on Both Facilitated Responsivity to Acute Restraint and Metabolic Responses to Chronic Stress.

To determine the effects of both corticosterone (B) and chronic stressors on acute ACTH responses to restraint, young male rats were exposed to streptozotocin-induced diabetes, cold (5-7 degreesC) or intracerebroventricular (icv) neuropeptide Y (NPY) for 5 d and then exposed to restraint within 2 h after lights on. Two groups of rats were studied: intact and adrenalectomized replaced with B pellets that maintained plasma B in the normal mean 24-h range of intact rats. In addition to ACTH and B responses to restraint on d 5, body weight, food intake, fat depots, glucose and other hormones were measured to determine the role of stress-induced elevations in B on energy balance. ACTH responses to restraint were normal in intact rats subjected to diabetes or cold. By contrast, there was no ACTH or B response to restraint in NPY-infused intact rats. All 3 groups of chronically stimulated adrenalectomized rats with clamped B had facilitated ACTH responses to restraint compared to their treatment controls. Overall food intake increased in all groups of stressed rats; however, augmented intake occurred only during the light in intact rats and equally in the light and dark in B-clamped rats. White adipose depot weights were decreased by both diabetes and cold and increased by NPY in intact rats; the decreases with cold and increases with NPY were both blunted and changes in fat stores were not significant in adrenalectomized, B-clamped rats. We conclude that: 1. diabetes- and cold-induced facilitation of restraint-induced afferent input to hypothalamic control of the hypothalamo-pituitary-adrenal (HPA) axis is opposed in intact rats by the elevated feedback signal of B secretion; 2. NPY does not induce facilitation of afferent stress pathways; 3. chronic stimulation of the HPA axis induces acute hyperresponsiveness of hypothalamic neurons to restraint provided that the afferent input of this acute stimulus is not prevented by B feedback; 4. stimulus-induced elevations in B secretion result in day-time feeding; 5. insensitivity of both caloric efficiency and white fat stores to chronic stress in adrenalectomized, B-clamped rats results from loss of normally variable B levels.

Journal Article↗
PubMedDate not supplied

Stone's enterostomy crushing clamp for modified Duhamel's procedure.

AIM: To evaluate the safety and advantages of the use of Stone's enterostomy crushing clamps in modified Duhamel procedure. MATERIAL AND METHODS: Prospective study at a tertiary care paediatric surgery centre between February 1994 through February 1998 involving all cases undergoing modified Duhamel procedure for Hirschsprung's disease. RESULTS: Twenty eight patients, ranging from 5 months to 14 years were included in the study. The clamp was found to be easier to apply, needed no extra pelvic dissection and there were no immediate or delayed complications. The children were more comfortable and could be mobilized out of bed sooner post-operatively. It is a much cheaper option than staplers. CONCLUSION: The Stone's enterostomy crushing clamp is a reasonably cheap, reusable, safe and effective alternative for the Kocher's clamp and stapling devices for modified Duhamel procedure.

Adolescent↗
PubMed1999

A preliminary study of acute responses to clamped alcohol concentration and family history of alcoholism.

BACKGROUND: The clamping method of alcohol administration was combined with a battery of dependent measures of frontal lobe brain function, and a novel index of acute adaptation, in a preliminary study in order to explore the paradigm's sensitivity to a familial history of alcoholism (FHA). METHODS: Ten family history-positive (FHP) and 10 family history-negative (FHN) adult social drinkers of both genders underwent alcohol clamping. Twenty minutes after the start of an intravenous infusion of alcohol, the breath alcohol concentration was clamped at a target of 60+/-5 mg/dl for 150 min. Initial and adaptive responses to alcohol were assessed using scalar indices of change. One index assessed initial improvements or impairments in brain function after alcohol. The other index assessed acute adaptation (tolerance or sensitization) to alcohol while the brain's exposure to alcohol was held constant. The battery of dependent measures included subjective perceptions, neuropsychological tests, saccadic eye-movement tasks, and event-related potential (ERP) tasks. Effect sizes for FHA were estimated for 10 dependent variables that showed adequate baseline test-retest reliability (r>0.6). RESULTS: FHP subjects showed less intense initial responses to alcohol in subjective perceptions, but greater changes in the latency of volitional saccades and ERP P3 components than did the FHN controls. FHP subjects generally showed greater acute tolerance to alcohol than did controls, who showed more instances of acute sensitization at this moderate breath alcohol concentration. Effect sizes for FHA exceeded 0.4 in more than half of the indices. CONCLUSIONS: The BrAC clamping paradigm assesses initial and adaptive responses of a battery of behavioral and electrophysiological measures of frontal lobe function to ethanol that appear both reliable and sensitive to FHA.

Adult↗
PubMed2000

Increased levels of basic fibroblast growth factor are found in the cross-clamped heart during cardiopulmonary bypass.

BACKGROUND: High concentrations of fibroblast growth factors (FGFs) are found in the heart. Even higher levels are measured during ischemia. Exogenous administration of FGF to ischemic myocardium promotes synthesis of collateral coronary circulation and induces local myocardial hypertrophy. The kinetics and the contribution of the heart and lungs to circulating basic FGF (bFGF) levels during cardiac surgery were characterized. PATIENTS AND METHODS: Plasma bFGF levels were measured in seven adults undergoing coronary artery bypass operations and 11 neonates undergoing congenital cardiac anomaly repair during cardiopulmonary bypass. RESULTS: In both the adult and the neonatal groups, bFGF plasma levels increased significantly immediately after removal of the aortic cross-clamp (adult group 15.43+/-6.3 aorta cross-clamped versus 29+/-4.1 after release, P=0.011; neonatal group 17.09+/-9.43 aorta cross-clamped versus 43.55+/-14.25 after release, P=0.004) and declined thereafter. In the adult group, higher levels of bFGF were recorded in blood recovered from the coronary sinus than in the aortic root during aortic cross-clamping (63.14+/-14.42 versus 43.86+/-12.05, P=0.011), and in both, levels were significantly higher than the peripheral measurements. CONCLUSIONS: Plasma bFGF levels increase during cardiopulmonary bypass. The source of this elevation is the lungs and heart.

Aged↗
PubMed2000

[Cerebral ischemia during carotid clamping: diagnosis and prevention].

A serious complication in carotid endarterectomy (CEA) is the occurrence or aggravation of neurological deficits caused by insufficient collateral cerebral blood flow during cross-clamping. At the moment, patients with failure of collateral circulation at this point cannot be identified preoperatively. Thus, intraoperative monitoring and methods to prevent clamping-related cerebral ischemia are required. To put this strategy into clinical practice there are several methods of monitoring cerebral function (e.g. surgery performed in awake patients, electroencephalography, somatosensory evoked potentials), changes of hemodynamic (e.g. carotid stump pressure, transcranial Doppler ultrasonography) or metabolic parameters (e.g. jugular bulb oximetry or transcranial oximetry). One technique that meets nearly all requirements of an ideal monitoring under general anesthesia is the use of somatosensory evoked potentials (SEPs). Registration of SEPs is simple to perform and indicates with a high sensitivity and specificity critical cerebral hypoperfusion during cross-clamping. Thus, SEPs monitoring indicates the necessity of shunt placement. As a result, the use of an indwelling shunt as the most effective method to prevent clamping ischemia can be limited to selected cases, avoiding the risks of shunting in patients with sufficient collateral flow. In addition, correct shunt function is immediately indicated by recovering potentials. Whether a combination of SEPs with transcranial Doppler measurements will be successful to provide additional information about cerebral embolisation should be determined.

Brain Ischemia↗
PubMed2000

Neonatal circumcision with Gomco clamp--a hospital-based retrospective study of 1000 cases.

OBJECTIVE: To evaluate the impact and safety of neonatal circumcision under a uniform hospital policy using Gomco Clamp (GC). DESIGN/METHODS: A retrospective analysis of 1000 consecutive cases of neonatal circumcisions done with Gomco clamp at the Armed Forces Hospital, Jubail, Saudi Arbia during the period January 1996 through December 1998. The outcome measures were the type and number of complications, incidence of inadequate circumcisions, redo procedures and the extent of parental satisfaction. RESULTS: There was 1.9% incidence of overall complications (n = 19) with mild to moderate bleeding in 6 cases (31.6% of complications), which settled with further compressive dressing. There were 4 cases (21%) of superficial sepsis and 2 frenular ulcers (10.5%), which required topical antibiotics. Four babies (21%) had soft Preputial adhesions that were separated easily under topical anaesthesia. There were 3 cases (16%) of inadequate circumcisions; however only one required a redo operation after one year. The other two were found adequate at further follow-up for two years and final appearance was acceptable to parents; 99.7% parents were satisfied with the final cosmetic appearance. CONCLUSION: The circumcision with Gomco clamp is safe and effective technique with reproducible results provided a particular care is taken in exact marking of the site on foreskin for excision and selecting a correct size of the clamp. Each hospital needs to develop its own policy keeping in view the population for best cosmetic results from circumcision to avoid disappointments and redo operations.

Circumcision, Male↗
PubMedDate not supplied

Liver transplantation with vena cava in situ and selective use of temporary portacaval shunt or portal clamping.

BACKGROUND/AIMS: The recipient hepatectomy with vena cava in situ in liver transplantation has overcome the need of venous-venous bypass thanks to temporary porta caval shunt or portal clamping. METHODOLOGY: 150 orthotopic liver transplants in 137 patients were performed and the vena cava in situ technique was used in 142 (venous bypass in 7, temporary porta caval shunt in 49, portal clamping in 87). The suprahepatic cava veins anastomosis was performed with Belghiti in 97 and piggyback techniques in 45. RESULTS: There were no differences in operative and warm ischemia times nor in blood requirements, while a greater stability of body temperature was documented in the vena cava In Situ group: in the latter temporary porta caval shunt preserved the temperature better than portal clamping (P < 0.01). In anhepatic phase mean artery pressure decreased in veno-venous bypass and increased in the vena cava In situ groups (P < 0.01). The venous return and the cardiac performances (anhepatic phase) were better preserved in the vena cava In Situ group. (P < 0.0001). CONCLUSIONS: Temporary portal caval shunt or portal clamping and piggyback or Belgiti Techniques allow a better hemodynamic stability through out the procedure, obviating the need for veno-venous bypass or fluid overload, if selectively used.

Adult↗
PubMed2001

[Fractionated-clamping for thoracoabdominal aortic aneurysm repair: report of 13 cases].

OBJECTIVE: Fractionated-clamping was applied to aneurysm repair in patients with thoracoabdominal aortic aneurysm(TAA), and its effects in decreasing operative mortality and severe complications such as renal failure and hemiplegia were discussed. METHODS: Using improved shunting and cross-clamping technique, we repaired 13 thoracoabdominal aortae and their branches (9 males and 4 females). TAA Crawford type: type I one case, type II two cases, type III two cases and type IV three cases. TAA dissection Debakey type: type I one case, type III four cases (including 2 of ruptured aneurysm) and aorta stenosis one case. RESULTS: Twelve procedures were performed successfully. One patient died of cardiac attack immediately before accomplishment of the operation with a operative mortality rate of 7.7% (1/13). Operative complications included acute necrotizing pancreatitis (1 case), ARDS (1), thoracic cavity bleeding (2), hemiplegia (1), and acute renal failure (1). The incidence rate of complications was significantly lower than that reported elsewhere. CONCLUSIONS: Fractionated-clamping for thoracoabdominal aortic aneurysm repair is a renovation on the basis of Crawford procedure and aorta bypass method. Clinical results demonstrated that the procedure decreases the surgical mortality and the incidence rate of dangerous complications. Fractionated clamping for aorta replacement is a reasonable procedure under general anesthesia at normal temperature.

Acute Kidney Injury↗
PubMed2002

Fractionated-clamping for thoracoabdominal aortic aneurysm repair: a modified Crawford technique.

OBJECTIVE: To apply fractionated-clamping for repair of thoracoabdominal aortic aneurysm (TAA), and evaluate its effects in decreasing surgical mortality and severe complications, such as renal failure and paraplegia, a modified crawford procedure were prospectively evaluated. METHODS: Using modified shunting and cross-clamping techniques, modified Crawford repair in 13 thoracoabdominal aorta patients were performed in the Vascular Division at Peking Union Medical College Hospital. TAA Crawford classification: 1 type I, 2 type II, 2 type III and 3 type IV TAA. Debakey classification: 1 type I, 4 type III (including 2 ruptured aneurysms), and 1 aortic coarctation. RESULTS: Thirteen procedures were performed successfully. One died of ventricular fibrillation just before completing the operation. Surgical mortality rate was 7.7% (1/13). Postoperative complications included 1 acute necrotic pancreatitis, 1 ARDS, 1 paraplegia, 1 acute renal failure, and 2 thoracic cavity bleeding. Total complication rate was 53.8% (7/13). CONCLUSIONS: Fractionated-clamping in thoracoabdominal aortic aneurysm repair is our modified Crawford procedure and aortic bypass. Clinical results demonstrate that our procedure decreased surgical mortality and major complication rate, and also alleviated viscera ischemic injury. Fractionated-clamping in aorta replacement is a practical procedure for TAA repair under general anesthesia at normal temperature.

Adult↗
PubMed1992

[Patch-clamp technique].

We first describe how to set up the system for patch-clamp recording and carry out the experiments with 4 different modes of conventional patch-clamp technique: cell-attached, whole-cell, inside-out and outside-out configurations. Thereafter, we mention about an improved 'nystatin perforated' patch-clamp technique which dissolves the fault of conventional patch-clamp techniques except the cell-attached mode.

Animals↗
PubMed2005

[Clinical applications of devitalized autogenous calvarial bone flaps fixed with titanium clamps (CranioFix) for cranioplasty].

OBJECTIVE: To evaluate reimplantation of devitalized autogenous calvarial bone flaps and the fixation of titanium clamps (CranioFix) for cranioplasty. METHODS: From March 2000 to December 2003, 21 patients underwent (1) delayed reimplantation of preserved autogenous bone flaps, which were removed during the initial operations for increased intracranial pressure and stored in a freezer and autoclaved before use, or (2) immediate reimplantation of tumor invaded bone flaps that were devitalized by boiling. All of these flaps were fixed with titanium clamps (CranioFix). Resorption of the bone flaps was monitored by skull roentgenograms and computed tomography (CT). The clinical and aesthetic results were evaluated. RESULTS: During the follow-up period of 6 to 30 months, no complications were found. There was slight resorption of the bone flaps in all cases, but the edge of the bone flaps was within the range of the titanium clamps according to skull roentgenograms and CT. Clinical and aesthetic results were highly satisfactory. CONCLUSIONS: It is simple and practical using devitalized autogenous calvarial bone flaps for cranioplasty. The firmness decreasing of the reimplanted bone flap due to resorption can be prevented greatly by titanium clamps (CranioFix).

Adolescent↗
PubMedDate not supplied

[Justa-renal aortic aneurysms repair: consequences of the supra-renal aortic clamping, based on an experience of 44 operated cases].

The present study is aimed at the evaluation of the consequences of the supra-renal aortic clamping in the surgical management of justa-renal aortic aneurysms, based on a personal experience of 44 cases operated on for the last 25 years. The series includes 42 men (95.5%) and 2 women (4.5%) with an average age of 70 years. All patients were operated on transperitonealy and the transection and reconstruction of left renal vein was made in 15 instances. Supra-renal aortic clamping and renal average ischemic time was 13'3 minutes, and no significant functional renal alterations could be noticed, nor the need for hemodialysis support. Contrarily, significant occlusive lesions of the renal arteries (4 instances) or the superior mesenteric artery (1 case) resulted as a mechanical consequences of the supra-renal aortic clamping. Three cases were recognized and repaired intraoperatively, through renal revascularization, one case was not diagnosed, coursed with anuric renal failure and death (mortality 2.2%). Patient with mesenteric artery occlusion developed an acute mesenteric ischemia which was successfully managed conservatively. The author concludes by enhancing the risks of the mechanical consequences arising from the supra-renal aortic clamping, namely renal or mesenteric ischemia. Its prompt recognition and repair seems mandatory, in order to avoid the severe and even fatal consequences that it may cause, raising the morbi-mortality rates that sometimes accompanies the surgical management of justa-renal aortic aneurysms.

Aged↗
PubMed1991

[Early prognostic factors of the surgery of aneurysms of the abdominal aorta with renal artery clamping].

The aneurysms of the abdominal aorta requiring suprarenal clamping are rare. Suprarenal clamping was required for only 43 of 544 aneurysms operated electively from 1981 to 1989. Twenty-five patients had a juxtarenal aneurysm, without any normal aortic segment under the renal arteries, and suprarenal clamping was therefore necessary while the upper anastomosis was being established (group I). Eighteen patients had an aneurysm enclosing the root of at least one renal artery (group II). Several prognostic factors have been assessed: patient's age, presence of preoperative renal insufficiency, of arterial hypertension or of coronary insufficiency, and revascularization method. Five patients died. Four of them belonged to group II and were over 75 years old. All presented with a preoperative renal insufficiency. Two of these deaths were caused by mesenteric infarction. Four cases of regressive postoperative renal insufficiency were observed in patients for whom renal clamping had lasted longer than 45 minutes. This study allowed outlining three prognostic factors: the patient's age, preoperative renal insufficiency, a period of renal ischemia exceeding 40 minutes. On the other hand, the severity of hypertension had no predictive value. Coronary insufficiency requires a strict hemodynamic surveillance, but is not a contraindication for revascularization.

Age Factors↗
PubMed1991

[Use of isolated myocytes and the patch clamp technic in pharmacological studies].

Effects of palmitylcarnitine, a toxic metabolite of ischaemia, on the electrophysiological properties of single ventricular myocytes of guinea pig were studied by means of patch clamp technique. Cells were enzymatically isolated by perfusing the heart with Ca-free Tyrode solution containing collagenase enzyme. Before experimentation, cells were allowed to recover in a regenerating solution for at least one hour at room temperature. An aliquot of the cell suspension was placed in a small (0.5 ml volume) chamber mounted on the stage of an inverted microscope. After a settling period of 10 minutes, the cells were superfused with Tyrode solution at a rate of 2 to 4 ml/min. Bath temperature was maintained at 35 degrees C. Patch electrodes were fabricated from glass capillary tubes. The electrodes having resistances of 2 to 4 M were connected to a LIST EPC-7 voltage clamp amplifier. The passive parameters (membrane resistance, time constant, capacitance), and resting and action potentials of the cells were recorded in current clamp mode, while the ionic currents (inward calcium, outward potassium) were recorded in voltage clamp mode. Palmitylcarnitine at 10(-6) M concentration increased the membrane resistance, time constant, and depolarized the cell membrane which was accompanied by a marked prolongation of the action potential duration. Under the effect of the drug, the outward potassium current responsible for the repolarization was decreased, while the inward calcium current responsible for the plateau phase was significantly increased mainly at positive membrane potentials. The steady-state activation and inactivation curves were shifted to less negative potentials. The results indicate that the changes in the membrane electrical properties play an important role in the development of the well-known arrhythmogenic effect of palmitylcarnitine.

Action Potentials↗
PubMed1991

Studies of myocardial protection in the immature heart. V. Safety of prolonged aortic clamping with hypocalcemic glutamate/aspartate blood cardioplegia.

This study tests the hypothesis that multidose, hypocalcemic aspartate/glutamate-enriched blood cardioplegia provides safe and effective protection during prolonged aortic clamping of immature hearts. Of 17 puppies (6 to 8 weeks of age, 3 to 5 kg) placed on vented cardiopulmonary bypass, five were subjected to 60 minutes of 37 degrees C global ischemia without cardioplegic protection and seven underwent 120 minutes of aortic clamping with 4 degrees C multidose aspartate/glutamate-enriched blood cardioplegia ([Ca++] = 0.2 mmol/L), preceded and followed by 37 degrees C blood cardioplegic induction and reperfusion. Five puppies underwent blood cardioplegic perfusion for 10 minutes without intervening ischemia to assess the effect of the cardioplegic solution and the delivery techniques. Left ventricular performance was assessed 30 minutes after bypass was discontinued (Starling function curves). Hearts were studied for high-energy phosphates and tissue amino acids. One hour of normothermic ischemia resulted in profound functional depression, with peak stroke work index only 43% of control (0.7 +/- 0.1 versus 1.7 +/- 0.2 gm x m/kg, p less than 0.05). There was 70% depletion of adenosine triphosphate (7.6 +/- 1 versus control 20.3 +/- 1 mumol/gm dry weight, p less than 0.05) and 75% glutamate loss (6.6 +/- 1 versus control 26.4 +/- 3 mumol/gm, p less than 0.05). In contrast, after 2 hours of aortic clamping with multidose blood cardioplegia preceded and followed by 37 degrees C blood cardioplegia, there was complete recovery of left ventricular function (peak stroke work index 1.6 +/- 0.2 gm x m/kg) and maintenance of adenosine triphosphates, glutamate, and aspartate levels at or above control levels adenosine triphosphate 18 +/- 2 mumol/gm, aspartate 21 +/- 1 versus control 2 mumol/gm, and glutamate 25.4 +/- 2 mumol/gm). Puppy hearts receiving blood cardioplegic perfusion without ischemia had complete recovery of control stroke work index. We conclude that methods of myocardial protection used in adults, with amino acid-enriched, reduced-calcium blood cardioplegia, can be applied safely to the neonatal heart and allow for complete functional and metabolic recovery after prolonged aortic clamping.

Adenosine Triphosphate↗