We studied the effects of mild hypothermia on cardiac contractility in isolated rabbit hearts perfused with Krebs-Henseleit solution according to the technique of Langendorff. Isovolumetric left ventricular pressure (LVP) was measured with a fluid-filled balloon. Hearts were paced after induction of atrioventricular block. At low heart rates (< 30 bpm) mild hypothermia (cooling to 30 degrees C) induced a 32% increase in LVP (146.5 +/- 10 mm Hg at 30 degrees C vs 110.7 +/- 13 mm Hg at 37 degrees C) but this positive inotropic response was progressively lost by increasing heart rate. At pacing rates >or=to90 bpm, lower systolic LVP, higher diastolic LVP, and lower positive and negative LV dP/dt were obtained in hypothermic (93 +/- 12 mm Hg, 55 +/- 18 mm Hg, 584 +/- 137 mm Hg/s, and 323 +/- 57 mm Hg/s at 210 bpm, respectively) compared to normothermic hearts (123 +/- 4 mm Hg, 10 +/- 4 mm Hg, 1705 +/- 145.5 mm Hg/s, and 1155 +/- 78 mm Hg/s at 210 bpm, respectively). The duration of mechanical diastole was reduced or suppressed in these hearts. Exposure to the beta-adrenoceptor agonist, isoproterenol, improved this diastolic dysfunction during hypothermia and pacing at high rates, suggesting that the sarcoplasmic reticulum Ca2+ uptake might be involved. Our data are also consistent with an increase in myofilament Ca (2+) sensitivity that is opposed by isoproterenol during hypothermia. (Anesth Analg 1996;82:975-81)

Contractility

Isovolumetric contraction

Ventricular pressure

10.1097/00000539-199605000-00015

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Citations (32)

The Role of Methylene Blue Spray to Keep Parathyroid Gland and Recurrent Laryngeal Nerve Safe During Thyroidectomy

Chirurgia (2023)

Ahmed Mohamed Kamal Ahmed Ramy Mikhail Nagiub A. Boutros Joseph Ellia Fahmy Hermina

sigur şi uşor de obţinut şi poate fi utilizat pentru a evita complicaţiile în timpul tiroidectomiei.Obiective: Scopul

Parathyroid gland

Hypoparathyroidism

10.21614/chirurgia.2023.v.118.i.3.p.291

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Citations (1)

A505 EFFECTS OF TRIIODOTHYRININE ON PRECONDITIONED ISCHEMIC RAT HEARTS

Anesthesiology (1997)

A. Boutros J.Z.N. Kleopoulos Laura Beaton C. Capuano

10.1097/00000542-199709001-00505

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THE EFFECT OF NUCLEOSIDE TRANSPORT INHIBITOR ON THE NORMOTHERMIC ISCHEMIC HEART

Anesthesiology (1991)

A. Boutros Willem Flameng H. Van Aken

10.1097/00000542-199109001-00521

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Ischemic preconditioning, adenosine and bethanechol protect spontaneously hypertensive isolated rat hearts.

Journal of Pharmacology and Experimental Therapeutics (1995)

A. Boutros Jie Wang

The frequency of chronic hypertension among cardiac surgery patients implies that experimental therapies that protect normotensive myocardium will be more clinically relevant if they also protect chronically hypertensive myocardium. We tested the effectiveness of three experimental therapies that protect normotensive myocardium from ischemic injury in both normotensive (NTR) and spontaneously hypertensive (SHR) isolated Sprague-Dawley rat hearts. Post-ischemic recovery of ATP, left ventricular end diastolic pressure, developed pressure, negative and positive left ventricular dP/dt (-dP/dt and +dP/dt) and coronary flow (CF) were compared in ischemically preconditioned, adenosine-pretreated, bethanechol-pretreated and untreated NTR and SHR isolated rat hearts. The effect of time on our preparation was evaluated by comparison to NTR and SHR hearts maintained in vitro for equal duration but not subjected to an ischemic insult (N = 7, all groups). Preconditioning, adenosine and bethanechol significantly improved recovery of ATP, left ventricular end diastolic pressure, developed pressure, -dP/dt, +dP/dt and coronary flow in both NTR and SHR hearts (P < 0.001 vs. untreated, all comparisons). Although recovery was not so pronounced in SHR hearts, these results suggest that experimental therapies that protect normotensive myocardium also protect chronically hypertensive myocardium. The effect of adenosine and that of ischemic preconditioning were nearly identical, and both treatments were significantly more cardioprotective than bethanechol in both NTR and SHR hearts (P < .05 and P < .001, respectively). This result suggests that adenosine buildup is more important than muscarinic receptor stimulation as a mechanism of the protection afforded by ischemic preconditioning.

Bethanechol

Ischemic Preconditioning

Ventricular pressure

Spontaneously hypertensive rat

10.1016/s0022-3565(25)12166-6

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Citations (45)

Doppler Guided Haemorrhoidal Artery Ligation in the Management of Symptomatic Hemorrhoids

QJM (2023)

A Abdel-Mageed Yasser Mohammed Abdel-Samea A. Boutros Ibram Nady Nashed Morshed

Abstract Background Hemorrhoid ligation with mucopexy is a simple, safe and cost-effective ambulatory treatment for the patients of symptomatic hemorrhoids. It can be performed on an outpatient or day care basis on grade 3 and 4 hemorrhoids to control bleeding and prolapsing hemorrhoids. Overall the results of hemorrhoid ligation and mucopexy were satisfactory with good control of patients complains. Objective To evaluate prospectively the outcome of Doppler-guided hemorrhoidal artery ligation in the management of symptomatic hemorrhoids. Patients and Methods Types of studies: A prospective study. Study setting: The study conducted in Ain Shams University Hospital (El Demerdash) under supervision of these supervisors. Study period: Six months. Results It is easy for the surgeon to learn it and acquire appropriate skills after a short learning curve. The HAL is a minimally invasive technique that is conceptually painless for patients since all maneuvers and sutures are endoanal and above the dentate line; this helps an early recovery and allows an ambulatory procedure. We must bear in mind that postoperative pain is often the most common concern for patients and professionals dealing with hemorrhoids. The results of HAL in this study show a very low postoperative pain rate (two patients_ lower than 7%); moreover, it is easily controlled with oral analgesia. One patient (3%) complained of retention of urine, which controlled easily. Conclusion Hemorrhoid ligation with mucopexy is a simple, safe and cost-effective ambulatory treatment for the patients of symptomatic hemorrhoids. It can be performed on an outpatient or day care basis on all grades of hemorrhoids to control bleeding and prolapsing hemorrhoids. Overall the results of hemorrhoid ligation and mucopexy were satisfactory with good control of patients complains.

Outpatient procedure

Anal stenosis

Outpatient clinic

10.1093/qjmed/hcad069.307

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