During routine dissection in the department of anatomy, the following anatomical variations of the phrenic nerve were observed on the right side of the neck of a 30-year-old male cadaver. The phrenic nerve, in its early course close to its origin, gave a communicating branch to the C5 root of the brachial plexus. At the level of the root of neck just before entering the thorax, the phrenic nerve was located anterior to the subclavian vein. This unique case of phrenic nerve variation gains tremendous importance in the context of subclavian vein cannulation, implanted venous access portals, and supraclavicular nerve block for regional anaesthesia.
Adult ; Brachial Plexus ; abnormalities ; Cadaver ; Dissection ; Humans ; Male ; Phrenic Nerve ; abnormalities ; Singapore

The use of antiepileptic drugs in pregnancy always presents challenges to doctors and their patients as it may have deleterious effects on the developing embryo. Lamotrigine is most commonly-prescribed drug among the newer antiepileptic drugs; hence, it has been selected for the present review. A number of studies pertaining to the safety of lamotrigine use during pregnancy have been reported, with differing results. Contradictory results have been reported in animals regarding lamotrigine teratogenicity, and human studies have also proven inconclusive. In many countries, human pregnancy registries are maintained to establish the safety of antiepileptic drugs during pregnancy, as all the different suggestions favour some over others, with specific antiepileptic combinations still being questioned. It is our hope that the present work may integrate the available disparate relevant facts into a directed effort towards minimising the risk of foetal compromise.
Abnormalities, Drug-Induced ; Animals ; Anticonvulsants ; adverse effects ; therapeutic use ; Epilepsy ; drug therapy ; Female ; Folic Acid Deficiency ; chemically induced ; Humans ; Pregnancy ; Teratogens ; pharmacokinetics ; pharmacology ; Triazines ; adverse effects ; therapeutic use

INTRODUCTIONWe aim to study and elucidate the safety profile of the antiepileptic doses of gabapentin during pregnancy, and to evaluate gabapentin-induced murine fetotoxicity at different dose levels.

METHODSA total of 60 pregnant mice, divided into 12 groups of five mice each, were exposed to gabapentin in four different doses of 0 (control), 113, 226, or 452 mg/kg body weight per day, at three different gestational stages including early gestation (1-6 days), mid-gestation (7-12 days), and late gestation (13-17 days). The pregnant mice were euthanized on day 18 of gestation, and foetuses were examined for teratogenic manifestations. Their brains were dissected and examined for gross changes, malformations, histological changes, and quantitative protein estimation.

RESULTSFoetal resorptions were observed in all treated groups with gabapentin administration at early gestation (1-6 days), and mid-gestation (7-12 days). On the other hand, growth retardation along with stunting in size of live foetuses were observed in all the mid-gestation (7-12 days), and late gestation (13-17 days) treated groups. Various gross malformations were observed with all the three doses (113, 226, and 452 mg/kg body weight per day) when gabapentin was administered at mid-gestation (7-12 days). The same trends were confirmed by gross and microscopic examination of brains along with quantitative protein estimation.

CONCLUSIONGabapentin should not be prescribed during pregnancy, as no therapeutic dose of gabapentin is safe during this period as far as the foetal well-being is concerned.

Abnormalities, Drug-Induced ; Amines ; adverse effects ; Animals ; Anticonvulsants ; adverse effects ; Body Weight ; Congenital Abnormalities ; prevention & control ; Cyclohexanecarboxylic Acids ; adverse effects ; Dose-Response Relationship, Drug ; Female ; Mice ; Mice, Inbred ICR ; Models, Chemical ; Pregnancy ; Pregnancy, Animal ; drug effects ; Teratogens ; gamma-Aminobutyric Acid ; adverse effects