The hemodynamic effects of intubation during nitroglycerin infusion in severe preeclampsia

S Longmire1, L Leduc, M M Jones

  • 1Department of Anesthesiology, Baylor College of Medicine, Houston, TX 77030.

The effectiveness of intravenous nitroglycerin infusion in lowering maternal blood pressure and in blunting the hemodynamic responses to endotracheal intubation was evaluated in six primigravid women with severe preeclampsia. Monitoring consisted of continuous electrocardiogram monitoring, arterial cannulation, and flow-directed pulmonary arterial catheterization in each patient. All patients underwent oxytocin induction of labor and crystalloid and/or colloid expansion to produce a pulmonary capillary wedge pressure of 10 to 15 mm Hg and a colloid osmotic pressure of greater than 17 mm Hg. Intravenous nitroglycerin was administered before induction of general anesthesia. The hemodynamic effects associated with endotracheal intubation revealed a change in the heart rate from 104 +/- 10 to 133 +/- 17 beats/min, an increase in mean arterial pressure from 134 +/- 12 to 164 +/- 32 mm Hg, and an increase in systemic vascular resistance from 1262 +/- 342 to 1351 +/- 259 dynes-sec-cm-5 that was accompanied by a small change in the cardiac index from 4.5 +/- 1.2 to 4.5 +/- 0.9 L.min-1.m-2.

Related Concept Videos

Adrenergic Antagonists: ɑ and β-Receptor Blockers01:31

Adrenergic Antagonists: ɑ and β-Receptor Blockers

Third-generation β-blockers, such as labetalol and carvedilol, represent a significant advancement in managing cardiovascular conditions. Unlike conventional β-blockers, which can induce peripheral vasoconstriction, third-generation drugs block α1 adrenoceptors. This promotes vasodilation through several mechanisms, such as increased nitric oxide production, inhibition of calcium ion entry, opening of potassium ion channels, and antioxidant action. Labetalol, for instance, is clinically...
Antihypertensive Drugs: Vasodilators01:23

Antihypertensive Drugs: Vasodilators

Vasodilators, primarily affecting the smooth muscles within arterial and venous walls, are commonly used for hypertension treatment. Medications such as minoxidil and hydralazine primarily target arteries and arterioles, while sodium nitroprusside acts on arterioles and venules. Minoxidil, functioning as a prodrug, is metabolized by hepatic sulfotransferase into its active form, minoxidil sulfate, after oral administration. This metabolite binds to the sulfonylurea receptor (SUR) component of...
Antianginal Drugs: Nitrates and β-Blockers01:16

Antianginal Drugs: Nitrates and β-Blockers

In cardiovascular health, antianginal drugs combat angina pectoris — a condition marked by chest pain owing to diminished blood flow to the heart.
Organic nitrates,  such as nitroglycerin, play a pivotal role. Once metabolized, they liberate nitric oxide, a molecular marvel. Nitric oxide triggers guanylyl cyclase and augments cGMP production. This biochemical cascade orchestrates the relaxation of vascular smooth muscles, ushering in vasodilation and enhancing coronary blood flow. Administered...
Treatment for Pulmonary Arterial Hypertension: Endothelin Receptor Antagonists01:18

Treatment for Pulmonary Arterial Hypertension: Endothelin Receptor Antagonists

Endothelins (ETs) are potent vasoactive peptides critical in the human body's various physiological and pathological processes. One of the most promising therapeutic strategies for treating pulmonary arterial hypertension (PAH) involves counteracting the effects of these endothelins using a class of drugs known as endothelin receptor antagonists.
ETs are synthesized through a complex sequence of enzymatic steps, primarily involving an enzyme referred to as endothelin-converting enzyme (ECE). Of...
Drug Delivery: Enteral Route01:18

Drug Delivery: Enteral Route

The enteral drug administration involves three primary routes: oral, sublingual, and buccal. Oral ingestion is the most prevalent, safe, economical, and convenient method for drug administration. However, it has certain drawbacks, including limited absorption due to the drug's low water solubility or poor membrane permeability, possible emesis from GI mucosa irritation, destruction of drugs by digestive enzymes or low gastric pH, and irregular absorption along with food or other drugs.
Drugs in...
Angina V: Nursing Management01:20

Angina V: Nursing Management

Angina, a symptom of myocardial ischemia, requires a structured nursing management approach to ensure effective care and prevent complications like myocardial infarction. Comprehensive nursing care involves assessing, diagnosing, planning, implementing interventions, and evaluating outcomes, all tailored to the individual patient's needs.Patient AssessmentNursing assessment begins with a detailed subjective evaluation of symptoms, which typically include chest pain or pressure radiating to the...