The Effects of Intravenous Nitroglycerin Bolus Doses in Reducing Hemodynamic Responses to Laryngoscopy and Endotracheal Intubation

Background. Hemodynamic responses to laryngoscopy and endotracheal intubation are transient in most patients. However, in some patients with a history of heart disease, systemic hypertension, or cerebrovascular disease, these may lead to dangerous complications. This study is aimed at determining the effectiveness of intravenous nitroglycerin bolus doses in reducing hemodynamic responses to laryngoscopy and endotracheal intubation. Material and Method. In this double-blind randomized controlled trial, 78 patients aged 18 to 65 years were randomly divided into three groups: 1 μg/kg dose of nitroglycerin (first group), 2 μg/kg dose of nitroglycerin (second group), and normal saline or placebo (third group). 26 samples were allocated for each group. Patients’ hemodynamic responses to laryngoscopy and endotracheal intubation were measured at different times. Data were analyzed using SPSS V 16. Results. Patients in the three study groups were similar in terms of age, sex, and weight. There was no significant difference between the mean saturation of peripheral oxygen (SPO2) and the mean heart rate between the three groups before endotracheal intubation and 1 to 10 minutes after intubation ( P > 0.05 ). The difference of mean arterial blood pressure between study groups was only significant in the first and fifth minutes after intubation. Mean systolic and diastolic blood pressure in the first, third, and fifth minutes after intubation was significantly lower in the intervention groups than the control group ( P < 0.05 ). However, no significant difference was observed between the intervention groups. The frequency of systolic blood pressure decrease was significantly different in the first and fifth minutes after intubation in the three study groups ( P < 0.05 ). Conclusion. Bolus doses of 1 and 2 μg/kg nitroglycerin in noncardiac elective surgery prevents the increase of mean systolic, diastolic, and arterial blood pressure but has no significant effect on heart rate after intubation.

Comprehensive clinical phenotyping of nitroglycerin infusion induced cluster headache attacks

Background Nitroglycerin administration allows the study of cluster headache attacks in their entirety in a standardised way. Methods A single-blind, placebo-controlled, cross-over study using weight-calculated intravenous nitroglycerin administration at 0.5 µg/kg/min over 20 minutes to study cluster headache attacks, including accompanying non-headache symptoms and cranial autonomic symptoms. Results Thirty-three subjects with cluster headache were included in the study; 24 completed all three study visits. Nitroglycerin-induced attacks developed in 26 out of 33 subjects (79%) receiving unblinded nitroglycerin infusion, and in 19 out of 25 subjects (76%) receiving single-blinded nitroglycerin infusion, compared with one out of 24 subjects (4%) receiving single-blinded placebo infusion. Episodic cluster headache subjects had a shorter latency period to a nitroglycerin-induced attack compared to the chronic cluster headache (CCH) subjects ( U = 15, z = −2.399, p = 0.016). Sixteen of nineteen episodic cluster headache (mean, 84%; 95% confidence interval, 66–100%) and 11 of 14 chronic cluster headache subjects developed a nitroglycerin-induced attack (79%, 54–100%) following the unblinded nitroglycerin infusion. Following the single-blinded nitroglycerin infusion, eight out of 13 episodic cluster headache (62%, 31–92%) and 11 out of 12 chronic cluster headache (92%, 73–100%) subjects developed nitroglycerin-induced attacks. Nitroglycerin induced non-headache symptoms in the majority of subjects receiving it: 91% in the open unblinded nitroglycerin visit and 84% in the single-blinded nitroglycerin visits, compared with 33% in the single-blinded placebo visit. Cranial autonomic symptoms were induced by nitroglycerin infusion, 94% in the open unblinded nitroglycerin visit and 84% in the single-blinded nitroglycerin visit, compared with 17% in the single-blinded placebo visit. Conclusion Intravenous weight-adjusted nitroglycerin administration in both episodic cluster headache in bout and chronic cluster headache is effective and reliable in inducing cluster headache attacks, cranial autonomic symptoms and non-headache symptoms.

Treatment of Congestive Heart Failure with Intravenous Nitroglycerin in Three Dogs with Degenerative Valvular Disease

ABSTRACT We described the use of IV nitroglycerin as adjunctive therapy in three canine patients with left congestive heart failure secondary to degenerative mitral valve disease. All three dogs were admitted for signs of respiratory distress and all were determined to be in left congestive heart failure by history, exam findings, thoracic radiographs, and echocardiography. In addition to standard therapy for left congestive heart failure, IV nitroglycerin was administered as a constant rate infusion at a dose of 1–6 mcg/kg/min. No adverse events attributable to the drug were noted. This is the first reported use of IV nitroglycerin in clinical veterinary patients. Further studies are warranted to investigate the safety, efficacy, and optimal dosing of IV nitroglycerin infusions in dogs with left congestive heart failure.

Palliative Use of Nitroglycerin to Improve Microvascular Circulation

Background: In the setting of critical illness, life preservation may come at the expense of limb as increasing concentration of vasopressors causes peripheral ischemia. When goals of care specify comfort measures, clinicians are faced with the difficult task of mitigating already present distal malperfusion while abiding to wishes of patient and patients’ families. Physical changes post vasopressor use, such as mottling of appendages or cooling of skin, can limit meaningful physical interactions with grieving family members. Case Presentation: We describe a case series of successful utilization of intravenous nitroglycerin to improve postvasopressor digital ischemia for comfort care measures to assist patient’s families in the grieving process. Conclusion: Following decision for comfort care measures, management for patient care goes beyond the realm of pain control. Dignified dying is an active process that requires clinicians to navigate care for both patient and patients’ families. By reversing the digital ischemia associated with vasopressors, patients’ families have the opportunity to give meaningful touch in setting of which it may be needed most.