1
|
34th William Fitts Jr oration: the parathyroid response to acute hemorrhage, sepsis, and multiple organ failure. ACTA ACUST UNITED AC 2009; 66:92-7. [PMID: 19131810 DOI: 10.1097/ta.0b013e3181929ce3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
2
|
|
3
|
Durward A, Guerguerian AM, Lefebvre M, Shemie SD. Massive diltiazem overdose treated with extracorporeal membrane oxygenation. Pediatr Crit Care Med 2003; 4:372-6. [PMID: 12831424 DOI: 10.1097/01.pcc.0000074273.50306.f5] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
OBJECTIVE To describe a case of massive diltiazem overdose with a good outcome achieved after early and aggressive supportive therapy. DESIGN Case report. SETTING Pediatric Critical Care Unit. PATIENT Sixteen-year-old adolescent girl. MEASUREMENTS AND MAIN RESULTS A 16-yr-old adolescent girl presented to the emergency department 6 hrs after the intentional ingestion of 40 300-mg sustained-release diltiazem tablets (12 g of Cardura CD). She was hypotensive and required a glucagon and epinephrine infusion despite initial fluid resuscitation with saline and intravenous calcium (1 g). Multiple asystolic cardiac arrests ensued which became increasingly refractory to high-dose epinephrine. Hemodynamic support was achieved with a 48-hr period of extracorporeal membrane oxygenation for atrial standstill. Severe multiorgan dysfunction ensued (cardiac, neurologic, renal, hepatic, gastrointestinal, hematologic, and metabolic). Plasma diltiazem and its metabolites were measured and its half-life was reported between 28 and 48 hrs. A sustained decline in plasma diltiazem levels and its metabolites was not observed after two periods of charcoal hemoperfusion. Recovery of organ function occurred with sinus rhythm noted on the ninth day. The patient made a full recovery and was discharged from the critical care unit after 15 days. CONCLUSIONS Although massive calcium channel blocker overdose can produce profound and prolonged cardiac or multiorgan dysfunction, its toxic effects may be reversible. Supportive therapy, particularly of the cardiovascular system, is the most important goal.
Collapse
Affiliation(s)
- Andrew Durward
- Pediatric Critical Care Unit, Hospital for Sick Children, Toronto, Canada
| | | | | | | |
Collapse
|
4
|
Hassan TB, Jagger C, Barnett DB. A randomised trial to investigate the efficacy of magnesium sulphate for refractory ventricular fibrillation. Emerg Med J 2002; 19:57-62. [PMID: 11777881 PMCID: PMC1725791 DOI: 10.1136/emj.19.1.57] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Ventricular fibrillation (VF) remains the most salvageable rhythm in patients suffering a cardiopulmonary arrest (CA). However, outcome remains poor if there is no response to initial defibrillation. Some evidence suggests that intravenous magnesium may prove to be an effective antiarrhythmic agent in such circumstances. STUDY HYPOTHESIS Intravenous magnesium sulphate given early in the resuscitation phase for patients in refractory VF (VF after 3 DC shocks) or recurring VF will significantly improve their outcome, defined as a return of spontaneous circulation (ROSC) and discharge from hospital alive. DESIGN A randomised, double blind, placebo controlled trial. Pre-defined primary and secondary endpoints were ROSC at the scene or in accident and emergency (A&E) and discharge from hospital alive respectively. SETTING, PARTICIPANTS, AND INTERVENTION: Patients in CA with refractory or recurrent VF treated in the prehospital phase by the county emergency medical services and/or in the A&E department. One hundred and five patients with refractory VF were recruited over a 15 month period and randomised to receive either 2-4 g of magnesium sulphate or placebo intravenously. RESULTS Fifty two patients received magnesium treatment and 53 received placebo. The two groups were matched for most parameters including sex, response time for arrival at scene and airway interventions. There were no significant differences between magnesium and placebo for ROSC at the scene or A&E (17% v 13%). The 4% difference had 95% confidence intervals (CI) ranging from -10% to +18%. For patients being alive to discharge from hospital (4% v 2%) the difference was 2% (95% CI -7% to +11%). After adjustment for potential confounding variables (age, witnessed arrest, bystander cardiopulmonary resuscitation and system response time), the odds ratio (95% CI) for ROSC in patients treated with magnesium as compared with placebo was 1.69 (0.54 to 5.30). CONCLUSION Intravenous magnesium given early in patients suffering CA with refractory or recurrent VF did not significantly improve the proportion with a ROSC or who were discharged from hospital alive.
Collapse
Affiliation(s)
- T B Hassan
- Accident and Emergency Department, The General Infirmary at Leeds, UK.
| | | | | |
Collapse
|
5
|
Hirotani T, Kameda T, Kumamoto T, Shirota S. Aortic arch repair using hypothermic circulatory arrest technique associated with pharmacological brain protection. Eur J Cardiothorac Surg 2000; 18:545-9. [PMID: 11053815 DOI: 10.1016/s1010-7940(00)00533-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
Abstract
OBJECTIVE Hypothermic circulatory arrest is a standard procedure for the treatment of aortic arch. However, there is a time limit for this procedure. There is now an urgent need to develop prophylactic measures to extend the time limit. We have used a pharmacological mixture of thiopental, nicardipine and mannitol for all patients undergoing circulatory arrest since 1991 to extend the safe limit. The purpose of this study was to analyze the neurological complications demonstrated by these patients and to evaluate the brain-protective effects of our measure. METHODS The clinical records of 75 consecutive patients undergoing an aortic arch repair using a hypothermic circulatory arrest technique during the past 8 years were retrospectively reviewed. Systemic cooling was continued until a total disappearance of EEG activity. Prior to circulatory arrest, 15 or 30 mg/kg of thiopental, 20 mg of nicardipine and 300 ml of mannitol were infused into the venous reservoir of a cardiopulmonary bypass circuit. Graft replacement was performed in all patients and the extent of replacement was a total aortic arch in 43 patients, a distal aortic arch in 17, a hemiarch in 13 and a distal aortic arch and a total descending aorta in two. RESULTS The duration of circulatory arrest ranged from 16 to 80 min (mean 41.5 min), and it exceeded 45 min in 37 patients. Operative mortality was 10.7% and two patients died of stroke. Three patients had permanent and three other patients had transient neural deficits. The incidence of stroke was 8.0% as a whole, and no correlation between the incidence of neurological complications and the duration of circulatory arrest was found. A multivariate analysis showed that the duration of circulatory arrest was determined as a predictor of neither operative mortality nor postoperative stroke. CONCLUSIONS The findings of the present study suggest that our pharmacological brain protection appears to be effective for safely extending hypothermic circulatory arrest.
Collapse
Affiliation(s)
- T Hirotani
- Department of Cardiovascular Surgery, Tokyo Saiseikai Central Hospital, 1-7-14 Mita, Minato-ku, 108-0073, Tokyo, Japan.
| | | | | | | |
Collapse
|
6
|
Ema M, Gebrewold A, Altura BT, Zhang A, Altura BM. Alcohol-induced vascular damage of brain is ameliorated by administration of magnesium. Alcohol 1998; 15:95-103. [PMID: 9476955 DOI: 10.1016/s0741-8329(97)00102-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Ethanol ingestion can cause irreversible neuronal and vascular damage in the brain and stroke-like events. Using an intact in vivo rat brain (pial) model, TV image-intensification, cultured cerebral vascular muscle cells, digital-image analysis, and a novel Mg2+ ion-selective electrode to measure extracellular ionized Mg2+, studies were designed to determine whether: 1) perivascular or systemic administration (i.v. or intra-arterial) of magnesium aspartate HCI (MgA) exert vasodilator effects on arterioles (65-130 microm o.d.) and venules (60-135 microm); 2) nonvasodilator doses of MgA could modify vascular spasms induced by BaCl2 and ethanol; 3) nonvasodilator doses of MgA could ameliorate or prevent the cerebral vascular damage induced by high doses of ethanol; and 4) ethanol depletes cerebral vascular muscle of intracellular Mg ions ([Mg2+]i). Perivascular application of MgA (0.01-100 micromol) produced dose-dependent vasodilatation of cerebral arterioles and venules; arterioles yielded greater vasodilator responses compared to venules. Nonvasodilator doses of Mg (1.0, 4.0 micromol/min), administered i.v. or intra-arterially, into a branch of the internal carotid artery, prevented: 1) the spasmogenic actions of ethanol and Ba2+; and 2) the vasculotoxic actions (rupture of postcapillary venules and focal hemorrhages) of ethanol. In addition, ethanol depleted cerebral vascular muscle cells of [Mg2+]i; blood levels of ionized Mg2+ rose after IP ethanol. Despite the fact that systemic infusion of low nonvasodilator doses did not result in dilatation of the pial arterioles and venules, plasma total and ionized Mg rose 18-230%, depending upon dose of MgA and time of plasma sampling. These data support the idea that Mg2+ can act as a local vasodilator on brain microvessels and possess antispasmodic properties on brain arterioles and venules. In addition, our results indicate that Mg may possess some unique cerebral vascular protective properties against the vasculotoxic effects of ethanol. Lastly, these findings suggest ethanol-induced cerebrovasospasm and vascular damage appear to be associated with a rapid loss of [Mg2+]i from cerebral vascular muscle cells.
Collapse
Affiliation(s)
- M Ema
- Department of Physiology, State University of New York, Health Science Center at Brooklyn, 11203, USA
| | | | | | | | | |
Collapse
|
7
|
Thel MC, Armstrong AL, McNulty SE, Califf RM, O'Connor CM. Randomised trial of magnesium in in-hospital cardiac arrest. Duke Internal Medicine Housestaff. Lancet 1997; 350:1272-6. [PMID: 9357406 DOI: 10.1016/s0140-6736(97)05048-4] [Citation(s) in RCA: 109] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND The apparent benefit of magnesium in acute myocardial infarction, and the persistently poor outcome after cardiac arrest, have led to use of magnesium in cardiopulmonary resuscitation. Because few data on its use in cardiac arrest were available, we undertook a randomised placebo-controlled trial (MAGIC trial). METHODS Patients treated for cardiac arrest by the Duke Hospital code team were randomly assigned intravenous magnesium (2 g [8 mmoles] bolus, followed by 8 g [32 mmoles] over 24 h; 76 patients) or placebo (80 patients). Only patients in intensive care or general wards were eligible; those whose cardiac arrest occurred in emergency, operating, or recovery rooms were excluded. The primary endpoint was return of spontaneous circulation, defined as attainment of any measurable blood pressure or palpable pulse for at least 1 h after cardiac arrest. The secondary endpoints were survival to 24 h, survival to hospital discharge, and neurological outcome. Analysis was by intention to treat. FINDINGS There were no significant differences between the magnesium and placebo groups in the proportion with return of spontaneous circulation (41 [54%] vs 48 [60%], p = 0.44), survival to 24 h (33 [43%] vs 40 [50%], p = 0.41), survival to hospital discharge (16 [21%] vs 17 [21%], p = 0.98), or Glasgow coma score (median 15 in both). INTERPRETATION Empirical magnesium supplementation did not improve the rate of successful resuscitation, survival to 24 h, or survival to hospital discharge overall or in any subpopulation of patients with in-hospital cardiac arrest.
Collapse
Affiliation(s)
- M C Thel
- Duke Clinical Research Institute, Duke University Medical Center, Durham, NC 27710, USA
| | | | | | | | | |
Collapse
|
8
|
Achike FI, Dai S, Ogle CW. Influence of pH changes on the actions of verapamil on vascular excitation-contraction coupling. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 1996; 1:207-212. [PMID: 21781683 DOI: 10.1016/1382-6689(96)00013-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/1995] [Revised: 02/14/1996] [Accepted: 02/25/1996] [Indexed: 05/31/2023]
Abstract
We have previously shown that pH changes alter the cardiovascular responses to verapamil in rat, in vivo and in isolated rat heart. The current study investigated the influence of pH changes on the actions of verapamil on potassium- or noradrenaline-stimulated contraction in rat tail arteries. The proximal 2-2.5 cm of ventral tail artery was bathed in and perfused initially (20-25 min) with physiological salt solution (pH 7.4) which was later made calcium-free at pH 7.4 (control), pH 7.2 (acidosis) or pH 7.67 (alkalosis). After equilibration each artery was exposed to verapamil following which the contractile responses to increasing concentrations of calcium were recorded. The patterns of responses in noradrenaline- or potassium-stimulated arteries were different. In normal conditions, the vasodilator effect of verapamil was predominant in potassium-stimulated arteries but less in the noradrenaline-stimulated preparations. With pH changes the effect of verapamil was enhanced more in noradrenaline- than in potassium-stimulated arteries. It is postulated that pathology-induced changes in the character of calcium channels could alter the effect of calcium channel blockers.
Collapse
Affiliation(s)
- F I Achike
- Department of Pharmacology, Faculty of Medicine, University of Hong Kong, 5 Sassoon Road, Hong Kong, Hong Kong China
| | | | | |
Collapse
|
9
|
|
10
|
Martin LG, Wingfield WE, Pelt DR, Hackett TB. Magnesium in the 1990's: Implications for Veterinary Critical Care. J Vet Emerg Crit Care (San Antonio) 1993. [DOI: 10.1111/j.1476-4431.1993.tb00108.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
|
11
|
|
12
|
Abu-Osba YK, Galal O, Manasra K, Rejjal A. Treatment of severe persistent pulmonary hypertension of the newborn with magnesium sulphate. Arch Dis Child 1992; 67:31-5. [PMID: 1536582 PMCID: PMC1590342 DOI: 10.1136/adc.67.1_spec_no.31] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Eight of nine newborn infants with severe persistent pulmonary hypertension of the newborn (PPHN), and a predicted mortality of 100%, and one infant with a predicted mortality greater than 94% based on alveolar-arterial oxygen tension difference [A-a)DO2) were treated with magnesium sulphate (MgSO4) as a life saving therapy after they failed to improve with conventional treatment. Magnesium at high serum concentrations decreases pulmonary pressures and is a muscle relaxant and sedative. Diluted MgSO4.7H2O solution (200 mg/kg) was given intravenously over 20-30 minutes. No changes in the treatment were made after MgSO4. Mean serum magnesium concentration was maintained between 2.88 and 5.67 mmol/l by continuous intravenous infusion (six infants). Baseline arterial oxygen tension (PaO2) and haemoglobin oxygen saturation had mean (SD) values of 4.66 (1.8) kPa and 60.4 (29.7)% respectively, which started to increase one hour after MgSO4 infusion, and increased significantly at six hours to 12.04 (7.07) kPa and 91.8 (10.88)% respectively. Arterial carbon dioxide tension (PaCO2) decreased and pH increased significantly after one hour compared with the baseline value. PaO2 increases are probably secondary to a decrease in pulmonary vascular resistance and pressure, decrease in a right to left shunt, better ventilation:perfusion ratio, and PaCO2 decrease and pH rise. Seven infants survived (77.8%). These results demonstrate the beneficial effect of magnesium in the management of PPHN when other accepted treatment fails, is contraindicated, or not available.
Collapse
Affiliation(s)
- Y K Abu-Osba
- Paediatric Department, King Faisal Specialist Hospital and Research Centre, Riyadh, Kingdom of Saudi Arabia
| | | | | | | |
Collapse
|
13
|
Tobey RC, Birnbaum GA, Allegra JR, Horowitz MS, Plosay JJ. Successful resuscitation and neurologic recovery from refractory ventricular fibrillation after magnesium sulfate administration. Ann Emerg Med 1992; 21:92-6. [PMID: 1539898 DOI: 10.1016/s0196-0644(05)82249-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A 46-year-old man suffered a witnessed cardiac arrest. Ventricular fibrillation persisted despite 62 minutes of basic and advanced cardiac life support measures in the field. On arrival in the emergency department, he received 4 g magnesium sulfate IV and was defibrillated successfully to normal sinus rhythm with the next countershock. The patient was discharged neurologically intact. We discuss the possible mechanisms of action and clinical use of IV magnesium sulfate in cardiac arrest.
Collapse
Affiliation(s)
- R C Tobey
- Residency in Emergency Medicine, Morristown Memorial Hospital, New Jersey
| | | | | | | | | |
Collapse
|
14
|
Kjellmer I. Etiology and pathophysiology of postasphyxial brain damage. Int J Technol Assess Health Care 1991; 7 Suppl 1:106-9. [PMID: 2037422 DOI: 10.1017/s0266462300012605] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In spite of major developments in prenatal supervision, perinatal asphyxia remains an important reason for the development of brain damage (18). Epidemiological investigations suggest that perinatal asphyxia actually represents a factor of increasing frequency as a cause of severe cerebral injury (9).
Collapse
|
15
|
Affiliation(s)
- Y K Abu-Osba
- Paediatric Department, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| |
Collapse
|
16
|
Iwatsuki N, Ono K, Takahashi M, Tajima T. The effects of nicardipine given after 10-minutes complete global cerebral ischemia on neurologic recovery in dogs. J Anesth 1990; 4:337-42. [PMID: 15235966 DOI: 10.1007/s0054000040337] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/1989] [Accepted: 06/12/1990] [Indexed: 11/29/2022]
Abstract
The effect of nicardipine (NC) on neurologic recovery from ischemic insult after 10-minutes complete global cerebral ischemia was evaluated in dogs by examination of neurologic recovery score (NRS: complete recovery = 100, death = 0). Ischemia was achieved by occlusion of ascending aorta, and NC, 10 microg.kg(-1) in bolus followed by infusion of 0.33 microg.kg(-1).min(-1) for 2 hours, was administered immediately after re-establishment of circulation. The mortality at 7th day was 2/9 in the control Copyright and 1/9 in the NC group (ns). NRS on 2nd day was 52.3 +/- 6.8 in the C and 70.6 +/- 6.5 in the NC ( P < 0.05), but that on 7th day did not differ between the two groups. The numbers of dogs recovered to over 80 in NRS on the 2nd day was 1/9 in the C and 5/9 in the NC ( P < 0.05), but that on the 7th day increased to 3/9 in the C and remained at 5/9 in the NC (ns). These results suggest that NC accelerates the early neurologic recovery from ischemic damage, but influences little the final outcome.
Collapse
Affiliation(s)
- N Iwatsuki
- Department of Anesthesiology, Tohoku University School of Medicine, Sendai, Japan
| | | | | | | |
Collapse
|
17
|
Achike FI, Dai S. Effects of blood gas/pH abnormalities on the cardiovascular actions of verapamil in rats. Clin Exp Pharmacol Physiol 1990; 17:653-63. [PMID: 2126229 DOI: 10.1111/j.1440-1681.1990.tb01366.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
1. The effects of hypoxaemia, hyperoxaemia, alkalosis, acidosis, hypocarbia with alkalosis or hypercarbia with acidosis on the blood pressure and pulse rate responses to verapamil were studied in chloralose-anaesthetized rats. 2. At a fixed stroke volume (10 mL/kg) and rate (80 strokes/min; except for the hypocarbic group at 160 strokes/min), hypoxaemia, hyperoxaemia, hypercarbia with acidosis, or hypocarbia with alkalosis was induced by artificial ventilation with gas mixtures containing 17% O2, 28% O2, 23% O2, with 5% CO2, or 17% O2, without CO2 respectively. Acidosis or alkalosis was produced by intravenous infusion of 1 mol/L HCl or 1 mol/L NaHCO3 respectively, in animals artificially ventilated with room air. 3. Changes in individual blood gas/pH parameters had no significant effect on blood pressure except for acidosis which caused a significant decrease. Effects on pulse rate were significant increases in the alkalosis and hypercarbia groups, decrease in the acidosis group, while in other conditions no significant changes were recorded. 4. In the controls, intravenous injections of verapamil 20-320 micrograms/kg caused dose-dependent increases in mean blood pressure, while effects on pulse rate were not marked. 5. The hypotensive responses to verapamil were significantly alleviated or enhanced in the presence of alkalosis or acidosis respectively. Verapamil also caused greater falls in pulse rate during acidosis. Effects of Po2 changes were not statistically significant. The influence of PCO2 changes remained unclear. 6. The present findings suggest that changes in blood pH may play a more important role than Po2 alterations in affecting the cardiovascular responses to verapamil in the presence of blood gas abnormalities.
Collapse
Affiliation(s)
- F I Achike
- Department of Pharmacology, Faculty of Medicine, University of Hong Kong
| | | |
Collapse
|
18
|
Levene MI, Gibson NA, Fenton AC, Papathoma E, Barnett D. The use of a calcium-channel blocker, nicardipine, for severely asphyxiated newborn infants. Dev Med Child Neurol 1990; 32:567-74. [PMID: 2391009 DOI: 10.1111/j.1469-8749.1990.tb08540.x] [Citation(s) in RCA: 65] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A continuous infusion of nicardipine was given to four severely asphyxiated fullterm infants who were at high risk for adverse outcome and had abnormal cerebral Doppler haemodynamic studies. The heart rate increased in all four infants and mean arterial blood pressure (MAP) fell in three. Two infants had a sudden and marked fall in MAP, together with severe impairment of skin blood-flow and a concurrent fall in cerebral blood-flow velocity. The serum level of nicardipine was less than 40ng/mL in all cases. The use of nicardipine, and possibly other calcium-channel blockers, may be associated with marked hypotension, and if there is no cerebral autoregulation, may cause further cerebral hypoperfusion, so use of these drugs in asphyxiated newborn infants should only be attempted if blood pressure is carefully monitored.
Collapse
Affiliation(s)
- M I Levene
- Department of Child Health, Leicester University School of Medicine
| | | | | | | | | |
Collapse
|
19
|
Charlap S, Kahlam S, Lichstein E, Frishman W. Electromechanical dissociation: diagnosis, pathophysiology, and management. Am Heart J 1989; 118:355-60. [PMID: 2665463 DOI: 10.1016/0002-8703(89)90197-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- S Charlap
- Department of Medicine, Maimonides Medical Center, Brooklyn, NY
| | | | | | | |
Collapse
|
20
|
Larson JS, Warner MA. Williams syndrome: an uncommon cause of supravalvular aortic stenosis in a child. JOURNAL OF CARDIOTHORACIC ANESTHESIA 1989; 3:337-40. [PMID: 2520660 DOI: 10.1016/0888-6296(89)90118-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- J S Larson
- Mayo Graduate School of Medicine, Rochester, MN 55905
| | | |
Collapse
|
21
|
Turlapaty P, Vary R, Kaplan JA. Nicardipine, a new intravenous calcium antagonist: a review of its pharmacology, pharmacokinetics, and perioperative applications. JOURNAL OF CARDIOTHORACIC ANESTHESIA 1989; 3:344-55. [PMID: 2520662 DOI: 10.1016/0888-6296(89)90120-8] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- P Turlapaty
- Mt. Sinai School of Medicine, Department of Anesthesiology, New York, NY 10029
| | | | | |
Collapse
|
22
|
Perspectives on Brain Resuscitation. Crit Care Nurs Clin North Am 1989. [DOI: 10.1016/s0899-5885(18)30925-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
23
|
Van Hoeyweghen R, Vercammen E, Bossaert L. Tolerance and pharmacokinetics of flunarizine after cardiac arrest. The Cerebral Resuscitation Study Group. Resuscitation 1989; 17 Suppl:S111-9; discussion S199-206. [PMID: 2551007 DOI: 10.1016/0300-9572(89)90095-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Neuronal calcium overloading after complete ischemia-anoxia of the brain might be the primary process initiating chemical cascades which lead to cell death. According to this hypothesis calcium-entry blocking agents act on the final common pathway of brain damage. Flunarizine, a selective calcium-entry blocker (without influence on heart rate and on cardiac contractile force), was administered to 12 unconscious patients, recovering from cardiac arrest (CA) of cardiac origin, according to a strict dose-range infusion protocol. Blood-pressure and heart rate (HR) were recorded before, during (t = 10 min, 20 min) and after (t = 30 min, 2 h, 4 h, 6 h, 8 h) each flunarizine infusion (maximum 4 infusions). A significant, although not clinically relevant, decrease in heart rate was noted during the first infusion. Systolic (SBP) and diastolic blood pressure (DBP) also decreased during the infusion without reaching statistical significance. Plasma levels of flunarizine were determined before and after each infusion (t = 15 min, 30 min, 1 h, 2 h, 4 h, 6 h, 8 h, 12 h). Flunarizine plasma concentrations declined very rapidly after cessation of each infusion. Sequential half-lives were in the order of 11-19 min and 5-7 h, and primarily reflect rates of distribution between the systemic circulation and the rapidly equilibrating tissues such as the brain. No substantial accumulation of flunarizine was described and plasma levels were proportional to the give dose. Therefore, flunarizine pharmacokinetics can be considered as linear for doses up to 50 mg.
Collapse
Affiliation(s)
- R Van Hoeyweghen
- Department of Intensive Care and Emergency Medicine, University Antwerp, UIA, Belgium
| | | | | |
Collapse
|
24
|
Affiliation(s)
- A Wauquier
- Department of Neuropharmacology, Janssen Pharmaceutica, Beerse, Belgium
| | | | | |
Collapse
|
25
|
Nishikawa T, Namiki A. The effects of verapamil on cerebrospinal fluid pressure in surgical patients. J Anesth 1987; 1:132-6. [PMID: 15235848 DOI: 10.1007/s0054070010132] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/1987] [Accepted: 05/29/1987] [Indexed: 11/30/2022]
Abstract
The effects of verapamil upon cerebrospinal fluid pressure (CSFP) were studied in twenty surgical patients without intracranial pathology who were divided into two groups of ten patients each: verapamil 0.075 mg.kg(-1) was given in group 1 and 0.15 mg.kg(-1) was given in group 2. A spinal needle was inserted into the subarachnoid space to permit continuous measurement of CSFP. Intravenous verapamil as a bolus produced a statistically significant increase in CSFP: from 6.0 +/- 3.5 (mean +/- SD) to 10.5 +/- 4.3 mmHg in group 1 ( P < 0.01), and from 6.2 +/- 3.1 to 12.6 +/- 3.8 mmHg in group 2 ( P < 0.01). CSFP after verapamil attained its maximum in 0.5-1.5 min, then gradually returned to control levels. Changes in CSFP were always associated with statistically significant decreases in arterial blood pressure and cerebral perfusion pressure, while the heart rate showed variable changes. It is concluded that a clinical dose of verapamil showed variable changes. It is concluded that a clinical dose of verapamil (0.075-0.15 mg.kg(-1)) has no neurological side effects in patients without intracranial hypertension. However, it must be emphasized that verapamil may increase CSFP to undesirable levels and should be avoided in patients with compromised intracranial compliance.
Collapse
Affiliation(s)
- T Nishikawa
- Department of Anesthesiology, Sapporo Medical College and Hospital, Sapporo, Japan
| | | |
Collapse
|
26
|
Abstract
Normal compensatory mechanisms protect the central nervous system (CNS) from moderate hypoxia and ischemia; however, after more severe ischemia progressive brain hypoperfusion ensues and irreversible damage occurs. Ischemic brain injury remains greatly significant clinically and elucidating the determinants of ischemic neuronal injury and death continues to challenge researchers. Although altered perfusion and decreased energy charge may contribute to the production of irreversible damage, the distribution of lesions seen after insult does not correspond with the degree of ischemic blood flow impairment, nor can neuronal energy deprivation explain the cell damage. Other factors, such as derangements in astrocyte function, calcium homeostasis, free radical metabolism, acid-base regulation and excitatory neurotransmitters also probably mediate ischemic neuronal death. Continued investigation to establish the cellular pathophysiology of cerebral ischemia can guide rational research and therapeutic strategies.
Collapse
Affiliation(s)
- J Kaplan
- Department of Emergency Medicine, University of Cincinnati Medical Center, OH 45267-0769
| | | | | | | |
Collapse
|
27
|
Abstract
The interest in the possibility of cerebral resuscitation has been growing exponentially during the last decade. It became clear that pharmacotherapeutic interaction can possibly alter the outcome of cerebral hypoxia/ischemia. The present review is an attempt to provide an organizational framework for a systematic integration of studies specifically dealing with pharmacological treatment post-insult.
Collapse
Affiliation(s)
- A Wauquier
- Department of Neuropharmacology, Janssen Pharmaceutica, Beerse, Belgium
| | | | | |
Collapse
|
28
|
Kumar K, Krause G, Koestner A, Hoehner T, White B. Effect of flunarizine on global brain ischemia in the dog: a quantitative morphologic assessment. Exp Neurol 1987; 97:115-27. [PMID: 3582557 DOI: 10.1016/0014-4886(87)90286-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The effects of flunarizine, a calcium antagonist, were evaluated in an experimental model of global brain ischemia produced by 15 min of cardiac arrest followed by resuscitation and reperfusion. One group of dogs received flunarizine (0.1 mg/kg intravenously during a 10-min period) at the onset of resuscitation. Another group of dogs underwent cardiac arrest, resuscitation, and reperfusion but did not receive flunarizine. A third group served as nonischemic control. In situ-fixed brains of all animals (nonischemic controls and the postischemic dogs after 8 h of reperfusion) were examined for anoxic ischemic injury. Quantitation of the ischemic neurons was carried out in parietal cortex, hippocampus, and cerebellum by using an image analysis system. Significant difference in the number of necrotic neurons between the flunarizine-treated group and the ischemic controls was noted in the hippocampus only; the mean percentage of necrotic neurons in the two groups being 14.8 +/- 9.6 and 29.3 +/- 12.1, respectively (P less than 0.05). These results indicate that flunarizine has an ameliorating effect on neuronal injury in the hippocampus that follows cardiac arrest in this experimental model of global brain ischemia. However, flunarizine was not found to be effective in reducing the ischemic neuronal damage in the cortex or the cerebellum.
Collapse
|
29
|
Fleischer JE, Lanier WL, Milde JH, Michenfelder JD. Lidoflazine does not improve neurologic outcome when administered after complete cerebral ischemia in primates. J Cereb Blood Flow Metab 1987; 7:366-71. [PMID: 3584269 DOI: 10.1038/jcbfm.1987.74] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
In order to investigate the effects of the calcium entry blocker lidoflazine on neurologic outcome in primates following an episode of global brain ischemia, 12 pigtail monkeys (Macaca nemestrina) were subjected to 17 min of complete cerebral ischemia, followed by 48 h of intensive care treatment and daily neurologic evaluations for 96 h. The monkeys were randomly assigned to receive, in a blind fashion, either lidoflazine 1.0 mg/kg (n = 6) or inactive lidoflazine solvent (n = 6) at 5 min, 8 h, and 16 h postischemia. One monkey in the lidoflazine group did not meet preestablished protocol criteria and was excluded from data analysis. The remaining monkeys were well matched for age, sex, and other physiologic variables. Neurologic outcome was not significantly different between the lidoflazine- and placebo-treated groups (p greater than 0.5). No monkey in either group achieved a normal neurologic exam by 96 h postischemia. Three lidoflazine-treated monkeys and two placebo-treated monkeys died prior to the 96-h neurologic evaluation. These deaths were judged to be neurologic in origin. The authors concluded that lidoflazine does not improve neurologic outcome in primates when administered after 17 min of complete cerebral ischemia.
Collapse
|
30
|
Hoehner PJ, Dean JM, Rogers MC, Traystman RJ. Comparison of thermal clearance measurement of regional cerebral blood flow with radiolabelled microspheres. Stroke 1987; 18:606-11. [PMID: 3590253 DOI: 10.1161/01.str.18.3.606] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
A thermal clearance technique for measuring cerebral blood flow is described and compared with the radiolabelled microsphere technique. The thermal technique involves measurement of the rewarming curve generated after bolus infusion of 4-5 ml of ice-cold saline into the common carotid artery with a subdural thermistor placed on the parietal cortex. Evaluation of the biexponential decay curves obtained with this technique demonstrated a close correlation with total hemispheric, parietal, and parietal gray blood flow determined by simultaneous microsphere measurement. Despite significant correlations (p less than 0.001), scatter in the data produced a broad 95% confidence interval, thus making interpretation of blood flow with the thermal clearance technique impossible. Furthermore, instrumentation with the thermal probe, which required opening of the dura, blunted the cerebral blood flow response to hypercapnia. We conclude that the major limitations of the thermal clearance technique include: nonhomogeneous clearance function, significant variability, and depression of CO2 reactivity. These limitations must be addressed before this technique can be used reliably in the laboratory.
Collapse
|
31
|
|
32
|
Ruiz E, Brunette DD, Robinson EP, Tomlinson MJ, Lange J, Wieland MJ, Sherman R. Cerebral resuscitation after cardiac arrest using hetastarch hemodilution, hyperbaric oxygenation and magnesium ion. Resuscitation 1986; 14:213-23. [PMID: 2433721 DOI: 10.1016/0300-9572(86)90065-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
This study was done to investigate the effects of hemodilution, hyperbaric oxygenation, and magnesium sulfate on cerebral resuscitation. Sixteen mongrel dogs were anesthetized, and monitored via pulmonary artery catheter, arterial catheter and electrocardiogram. A left lateral thoracotomy was done. Ventricular fibrillation was obtained by application of a 6-volt AC current. Mechanical ventilation was stopped. Total arrest time was 12 min. All dogs were cardiac resuscitated within 6 min using internal massage, ventilation, bicarbonate, epinephrine and internal defibrillation. The animals were then randomized into three groups. Group I represented controls, and were not treated. Group II dogs received normvolemic hemodilution using hetastarch (Hespan) containing magnesium sulfate (2000 mg/l), resulting in a hematocrit of 20%-30%. Group III dogs received the above hemodilution plus compression in a hyperbaric oxygen chamber to 2 atmospheres absolute. Critical care management and hourly neurologic scoring was performed for 7 days by blinded observers. All dogs at the time of death underwent autopsies for gross study. Data analysis revealed no statistical difference among the three groups with respect to survival time, cardiac function or neurologic scoring.
Collapse
|
33
|
Sakabe T, Nagai I, Ishikawa T, Takeshita H, Masuda T, Matsumoto M, Tateishi A. Nicardipine increases cerebral blood flow but does not improve neurologic recovery in a canine model of complete cerebral ischemia. J Cereb Blood Flow Metab 1986; 6:684-90. [PMID: 3793804 DOI: 10.1038/jcbfm.1986.124] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The effects of the calcium entry blocker nicardipine on CBF, CMRO2, and neurologic outcome following 10 min of complete cerebral ischemia were examined in dogs. In CBF and CMRO2 studies, the CBF in the untreated group (seven dogs) and the nicardipine group (seven dogs; 20 micrograms kg-1 at 30 min postischemia and a subsequent infusion of 2 micrograms kg-1 min-1 for 90 min) initially increased to 300-400% and then returned to preischemic values at 30 min postischemia. Thereafter the CBF in the untreated group significantly decreased to 50% of preischemic values for the following 90-min period (hypoperfusion), while the CBF in the nicardipine group did not differ from preischemic values. The CMRO2 in both groups decreased to approximately 50-80% of preischemic values after 15 min postischemia and did not differ between the groups throughout the study. In neurologic outcome studies, 18 dogs were divided into three groups (of six dogs each): untreated; saline infusion only, posttreated; nicardipine as in CBF and CMRO2 studies, pretreated; nicardipine 20 micrograms kg-1 at 2 min preischemia and a subsequent infusion of 2 micrograms kg-1 min-1 from immediately postischemia to 120 min postischemia. Nicardipine treatment initiated either before or after ischemia failed to improve neurologic outcome at 48 h postischemia. Thus, the increase of postischemic global CBF by nicardipine is not accompanied by neurologic recovery in a canine model of complete cerebral ischemia.
Collapse
|
34
|
Abstract
During open-heart operations, periods occur during which the blood supply to the heart is stopped. Myocardial damage can be limited by cooling and induction of electromechanical arrest (cardioplegia). Many animal studies and some clinical trials provide strong evidence for the use of calcium antagonists, such as nifedipine, verapamil hydrochloride, diltiazem hydrochloride, and lidoflazine, as adjuncts to cardioplegia to optimize the protection. Salutary effects of calcium antagonists are discussed in regard to possible mechanism of action, application time, and efficacy during hypothermia. A major conclusion is that virtually no negative effects on cardiac protection have as yet been described in experimental or clinical studies, apart from short-term negative inotropic responses, while there is an increasing body of positive evidence for their efficacy. A new development is the use of these drugs for regional cardioplegia during dilation of coronary arteries (transluminal angioplasty).
Collapse
|
35
|
Garrison HG, Hansen AR, Palladino GW, Fillipo DC, Proctor HJ. Effect of nifedipine on cerebral high-energy phosphates after cardiac arrest and resuscitation in the rat. Ann Emerg Med 1986; 15:685-91. [PMID: 3085559 DOI: 10.1016/s0196-0644(86)80426-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
We studied the effect of nifedipine, a calcium entry blocker, on the recovery of cerebral adenosine triphosphate (ATP), creatine phosphate (CP), and lactate levels following resuscitation from cardiac arrest. Using the cardiac arrest and resuscitation model of de Garavilla, Babbs, and Tacker with an arrest time of eight minutes, 76% of the animals arrested were resuscitated with an average intermittent abdominal compression-CPR time of 3.3 minutes. Rats were assigned randomly to the following groups: nonischemic; eight minutes of arrest without resuscitation; and postresuscitation treatment with either IV normal saline; 3 micrograms/kg nifedipine; 10 micrograms/kg nifedipine; or 30 micrograms/kg nifedipine. Treated animals were sacrificed at either 20 or 120 minutes thereafter. As expected, after eight minutes of cardiac arrest, the levels of ATP and CP dropped to near 0 and rebounded in all resuscitated animals. By 120 minutes after resuscitation, rats given the 10-micrograms/kg dose of nifedipine had levels of ATP equivalent to nonischemic values. Return of CP values to nonischemic levels was seen only at the 3-micrograms/kg dose and was independent of time of measurement. The ATP and CP levels in these nifedipine-treated groups were significantly better when compared to saline-treated controls. There were no treatment-dependent differences in lactate levels. We conclude that clinically appropriate doses of nifedipine had a beneficial effect on the recovery of cerebral high-energy phosphates after cardiac arrest and resuscitation.
Collapse
|
36
|
Robertson CS, Foltz R, Grossman RG, Goodman JC. Protection against experimental ischemic spinal cord injury. J Neurosurg 1986; 64:633-42. [PMID: 3950746 DOI: 10.3171/jns.1986.64.4.0633] [Citation(s) in RCA: 115] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The authors have studied the protection against ischemic damage to rabbit spinal cord by pretreatment with agents that block neuronal activity and directly or indirectly reduce tissue metabolism. Hypothermia, thiopental, magnesium, lidocaine, and naloxone were used to pretreat the spinal cord prior to ischemia. Hypothermia and thiopental provided comparable protection: they each increased the duration of ischemia required to produce neurological deficits in 50% of the animals from 26 to 41 minutes. They also increased from 10 to 30 minutes the time that the postsynaptic waves of the spinal somatosensory evoked potential (SSEP) could be absent and the animal still have neurological recovery. Hypothermia and thiopental, when used together, increased the duration of ischemia required to produce neurological deficits to 57 minutes in 50% of the animals. Naloxone increased the duration of ischemia required to produce neurological deficits to 36 minutes in 50% of the animals, and increased to 20 minutes the time that the postsynaptic waves of the SSEP could be absent and the animal still have neurological recovery. Magnesium pretreatment improved neurological outcome, possibly by improving collateral circulation as the SSEP did not fail completely during aortic occlusion in all animals. Lidocaine was not beneficial, perhaps because of the prolonged hypotension that resulted.
Collapse
|
37
|
Krause GS, Kumar K, White BC, Aust SD, Wiegenstein JG. Ischemia, resuscitation, and reperfusion: mechanisms of tissue injury and prospects for protection. Am Heart J 1986; 111:768-80. [PMID: 3513507 DOI: 10.1016/0002-8703(86)90114-6] [Citation(s) in RCA: 74] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Since its introduction in 1960, CPR has evolved into a complex program involving not only the medical community but also the lay public. Currently, program activities include instruction of the lay public in basic life support techniques, development and deployment of emergency medical systems, recommendations for drug protocols for advanced cardiac life support and, most recently, introduction of new methods for tissue protection following resuscitation. After 25 years of experience, we are beginning to understand the pathophysiology of tissue ischemia during cardiac arrest and the interventions required to improve chances of survival and quality of life of the cardiac arrest victim. Recent data in the literature suggest that modification of certain interventions in the resuscitation program may be needed. The poor neurologic outcomes with prolonged standard CPR show that it is not protective after 4 to 6 minutes of cardiac arrest. Modifications to this technique, including SVC-CPR or IAC-CPR, have not been shown to increase resuscitability or hospital discharge rates. Human studies of open-chest cardiac massage are needed to evaluate this option. Defibrillation is the definitive treatment for ventricular fibrillation. Greater emphasis should be placed on the earliest possible delivery of this treatment modality. Computerized defibrillators may provide greater and earlier access to defibrillation in the homes of patients at high risk of ventricular fibrillation. They may also be applicable by untrained public service personnel (police and firemen), individuals in geographically inaccessible areas (aircraft), or emergency medical technicians in rural areas where skill retention is a significant problem. Calcium has no proved benefit in cardiac resuscitation. There is biochemical evidence that it may be harmful in brain resuscitation. Its use in resuscitation should be discontinued. The dose of epinephrine currently advocated in the ACLS protocols may be inadequate to increase aortic diastolic pressure and coronary and cerebral perfusion pressures and thus aid resuscitation. Animal studies indicate that substantial increases in the current dosage are needed to achieve these effects. Human studies are needed to verify these results. A role for calcium antagonists in the treatment of postarrest encephalopathy has been demonstrated in animals and is currently undergoing clinical trials. Iron-dependent lipid peroxidative cell membrane injury may be important in the pathogenesis of postarrest encephalopathy. Animal studies suggest that the iron chelator deferoxamine may have a significant therapeutic role in the treatment of postarrest encephalopathy.
Collapse
|
38
|
White BC, Krause GS, Aust SD, Eyster GE. Postischemic tissue injury by iron-mediated free radical lipid peroxidation. Ann Emerg Med 1985; 14:804-9. [PMID: 4025973 DOI: 10.1016/s0196-0644(85)80062-7] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Cell damage initiated during ischemia matures during reperfusion. Mechanisms involved during reperfusion include the effects of arachidonic acid and its oxidative products prostaglandins and leukotrienes, reperfusion tissue calcium overloading, and damage to membranes by lipid peroxidation. Lipid peroxidation occurs by oxygen radical mechanisms that require a metal with more than one ionic state (transitional metal) for catalysis. We have shown that cellular iron is delocalized from the large molecules where it is normally stored to smaller chemical species during postischemic reperfusion. Postischemic lipid peroxidation is inhibited by the iron chelator deferoxamine. Intervention in the reperfusion injury of membranes by chelation of transitional metals is a new and promising therapeutic possibility for protection of the heart and brain.
Collapse
|
39
|
Nayini NR, White BC, Aust SD, Huang RR, Indrieri RJ, Evans AT, Bialek H, Jacobs WA, Komara J. Post resuscitation iron delocalization and malondialdehyde production in the brain following prolonged cardiac arrest. JOURNAL OF FREE RADICALS IN BIOLOGY & MEDICINE 1985; 1:111-6. [PMID: 3836237 DOI: 10.1016/0748-5514(85)90014-5] [Citation(s) in RCA: 75] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Assays for brain tissue malondialdehyde (MDA) and low molecular weight chelated (LMWC) iron were used to examine samples of the cerebral cortex obtained from dogs 2 h after resuscitation from a 15-min cardiac arrest. The effect of post-resuscitation treatment with lidoflazine and/or desferrioxamine was similarly examined. Non-ischemic brain samples had LMWC iron levels (in nmol/100 mg tissue) of 12.32 + 2.60 and MDA levels (in nmol/100 mg tissue) of 8.46 + 1.35. Animals subjected to cardiac arrest and resuscitation and standard intensive care (SIC) had LMWC iron levels of 37.04 + 4.58 (p less than .01 against non-ischemic controls) and MDA levels of 12.24 + 1.9 (p less than .05 against non-ischemic controls). All treatment interventions significantly reduced the LMWC iron (p less than .05), but only treatment with desferrioxamine alone significantly reduced MDA (p less than .05), although a trend toward reduction of the MDA was also evident in animals treated with both desferrioxamine and lidoflazine. LMWC iron levels are increased in the post-ischemic brain, and this increase may be related to lipid peroxidation in the brain following resuscitation from cardiac arrest. These changes are probably pathologic and are amenable to pharmacologic intervention.
Collapse
|
40
|
Morgan KJ, Stampley GL, Zabik ME, Fischer DR. Magnesium and calcium dietary intakes of the U.S. population. J Am Coll Nutr 1985; 4:195-206. [PMID: 4019942 DOI: 10.1080/07315724.1985.10720076] [Citation(s) in RCA: 68] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Dietary intake levels of calcium and magnesium, as well as calcium/magnesium ratios, were assessed for 12 age/sex groups of the U.S. population through use of USDA's 1977-78 Nationwide Food Consumption Survey. Results indicated that a majority of the U.S. population consumed less than recommended amounts (NRC-RDA) of both calcium and magnesium. Approximately 60% of 0 to 5 year olds and 40% of 6 to 11 year olds had average daily calcium intakes of less than 800 mg, while 60 and 85% of the male and female adolescents, respectively, had intakes below the recommended level of 1,200 mg/day. Approximately 80 to 85% of the adult female groups and 50 to 65% of the adult male groups had average intakes below recommended levels. With the exception of children ages 0 to 5 years, the average daily magnesium intakes of all age/sex classes were below the NRC-RDA. Magnesium consumption was particularly low among adolescent females, adult females, and elderly men, with 85, 80-85 and 75%, respectively, of the population groups having average magnesium intakes below their respective NRC-RDA. Furthermore, the majority of the population groups did not consume appropriate proportions of these two minerals to obtain optimal calcium/magnesium ratios. While adolescent females and adult females had more appropriate ratio values than other segments of the population, these ratios principally resulted from their very low intakes of calcium. The most inappropriate calcium/magnesium ratios, observed for children, male adolescents, and young adult males, were, in general, due to their more appropriate calcium intakes and their low magnesium intakes.
Collapse
|
41
|
Schwartz AC. Neurological recovery after cardiac arrest: clinical feasibility trial of calcium blockers. Am J Emerg Med 1985; 3:1-10. [PMID: 3882095 DOI: 10.1016/0735-6757(85)90002-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
In order to determine whether the calcium blockers verapamil and/or magnesium sulfate decrease neurological morbidity after cardiac arrest, all out-of-hospital cardiac arrests (290) occurring during a nine-month period in five participating hospitals were retrospectively studied. Twenty-nine patients met the criteria for inclusion in this study. Each had an unwitnessed, out-of-hospital cardiac arrest and was comatose (no purposeful response to pain) 20 minutes after the restoration of spontaneous circulation (ROSC). Eighteen patients (calcium blocker group) received verapamil and/or magnesium sulfate at some point after ROSC, while eleven patients received standard ACLS therapy (control group). Age, arrest time, cardiopulmonary resuscitation (CPR) time, and cerebral ischemic time were comparable in the two groups. In the calcium blocker group, seven of 18 patients regained consciousness, and six of these seven survived. All six survivors appeared neurologically normal upon discharge and at three and six months of follow-up. While no demonstrably adverse effects were seen after the administration of magnesium sulfate, 56% of the patients who received verapamil had a significant drop in blood pressure. In the control group, three of 11 patients regained consciousness and two of the three left the hospital alive. Both survivors were disabled--one severely and one moderately. Follow-up after three and six months revealed no significant improvement in their disability. Overall, six of 18 patients experienced clinically complete neurological recovery in the calcium blocker group, while none of the 11 patients in the control group made a complete neurological recovery (P = 0.06).
Collapse
|
42
|
|
43
|
White BC, Winegar CD, Jackson RE, Joyce KM, Vigor DN, Hoehner TJ, Krause GS, Wilson RF. Cerebral cortical perfusion during and following resuscitation from cardiac arrest in dogs. Am J Emerg Med 1983; 1:128-38. [PMID: 6680612 DOI: 10.1016/0735-6757(83)90080-3] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Perfusion of the cerebral cortex during closed chest CPR in dogs, generating systolic pressures of 60 to 70 mmHg, is only 10% of pre-arrest blood flow. In contrast, internal cardiac massage produces normal cortical perfusion rates. Following a 20-min perfusion arrest, during pressure controlled reperfusion, cortical flow rates decay to less than 20% normal after 90 min of reperfusion. This appears to be due to increasing cerebral vascular resistance, and is not due to rising intracranial pressure. The post-arrest cortical hypoperfusion syndrome is prolonged with cortical flow remaining below 20% normal up to 18 hr post arrest. The use of a variety of calcium antagonists, including flunarizine, lidoflazine, verapamil, and Mg2+, immediately post-resuscitation maintains cerebral vascular resistance and cortical perfusion at normal levels. A prospective blind trial of the calcium antagonist lidoflazine following a 15-min cardiac arrest in dogs and resuscitation by internal massage, demonstrates amelioration of neurologic deficit in the early postresuscitation period.
Collapse
|