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Sabaratnam Arulkumaran

Publications and source records attributed to Sabaratnam Arulkumaran.

12 recordsLinked to original sources
PubMed2004

Misoprostol: a quarter century of use, abuse, and creative misuse.

Misoprostol is a prostaglandin E1 analog originally intended for use to prevent NSAID-induced gastric ulcers. However, because of its cervical ripening and uterotonic property, misoprostol has become one of the most useful drugs in obstetrics and gynecology. Misoprostol has proven to be a very convenient and flexible drug because of its formulation as a tablet that is stable and that can be administered orally, rectally, vaginally and by the sublingual route. Beginning with its abuse for illegal abortion in the late 1980s, misoprostol has quickly become established as one of the most effective drugs for terminating pregnancies in the first and second trimesters, as well as for inducing labor in the third trimester. Its use for routine prevention of postpartum hemorrhage has not been so successful, partly as the high doses required for this indication often result in troublesome side effects. Despite the large body of medical evidence about its efficacy and relative safety, the use of misoprostol in pregnant women remained off-label until the spring of 2002.

Abortifacient Agents, Nonsteroidal↗
PubMed2003

Comparison of potassium currents in human decidua before and after the onset of labor.

The human decidua plays a prominent role in the signaling between maternal and fetal tissues. It also secretes a plethora of molecules that modulate uterine function. Ion-channel activity underpins many cellular functions; however, the channels in human decidua have not been characterized in any detail. We have used the whole-cell recording mode of the patch-clamp technique to carry out current-clamp and voltage-clamp recordings of membrane properties and whole-cell potassium (K+) currents of freshly isolated decidual stromal cells. Decidual tissue was obtained from women after spontaneous vaginal delivery (SVD) or elective cesarean section (CS). Cells from both groups generated action potentials, the overshoots and durations of which were dependent on extracellular calcium levels, inhibited by cobalt and enhanced by barium. Potassium current (IK) density was higher in the CS than in the SVD group. Outwardly directed currents were heterogeneous with respect to their activation/inactivation profiles and exhibited outward rectification. The main difference between the SVD and CS group was the presence of a sustained current component in CS cells that is tetraethylammonium chloride-resistant and appears to be unaffected by E-4031. No evidence for the activation of any calcium-activated K+ currents was obtained. We propose that human parturition is associated with subtle changes in K+ channel remodeling, reflecting the transition from uterine quiescence to activation and stimulation. An understanding of the signal transduction events underlying these process may eventually lead to novel approaches to prevent preterm labor via decidual rather than myometrial intervention.

4-Aminopyridine↗
PubMed2003

Medical and conservative surgical management of postpartum hemorrhage.

Massive postpartum hemorrhage (PPH) is a major cause of maternal mortality in the United Kingdom and worldwide. Life-threatening PPH occurs with a frequency of 1 in 1000 deliveries in the developed world. In the latest triennial Why Mothers Die: Confidential Enquiries into Maternal Deaths in the United Kingdom (1997-1999), PPH was the fifth most common cause of maternal mortality. In this review, we discuss the role of medical management in primary PPH and the use of the "tamponade test" when such management fails. The less radical surgical options discussed include uterine compression sutures, uterine or internal iliac artery ligation, and arterial embolization, all of which have the advantage of potentially preserving reproductive function. Radical surgical options, including subtotal or total hysterectomy, are not discussed in this review. A systematic or algorithmic method of tackling the problem is described. The suggested management approach is likely to reduce maternal morbidity from bleeding, hysterectomies, and maternal deaths.

Arteries↗
PubMed2003

Pituitary and adrenal disorders complicating pregnancy.

PURPOSE OF REVIEW: Confidential enquiries of maternal deaths in the UK for 1997-1999 revealed that the number of indirect deaths from medical conditions exacerbated by pregnancy was greater than deaths from conditions directly caused by pregnancy. Indirect maternal deaths accounted for 36% of all deaths. Although neoplastic disorders of the pituitary and adrenal glands are very rare during pregnancy, they can be potentially fatal. The rarity of these disorders may pose difficulty in formulating an optimum plan of management. Biochemical tests that can be performed in the non-pregnant state may be of little value during pregnancy. The presence of a fetus may also influence the type and timing of intervention. RECENT FINDINGS: A few case reports have been reported in the literature, but unfortunately no large series to develop guidelines or protocols. However, endoscopic surgical procedures have recently been used in their management with good outcomes. New drugs such as octreotide and lanreotide are increasingly being used during pregnancy. Although too soon to assess the safety of these new treatments, results so far have been very encouraging. SUMMARY: Awareness of these potentially fatal neoplastic disorders of the pituitary and adrenal glands, coupled with early diagnosis and appropriate treatment, may help improve maternal and fetal outcomes. Advances in imaging techniques and endoscopic procedures are also likely to change clinical practice. Various new treatment options are being reported in the literature, but they are not supported by randomized, controlled trials. Further research is needed to determine their safety and efficacy during pregnancy.

Adrenal Gland Neoplasms↗
PubMed2003

Neonatal subgaleal hemorrhage and its relationship to delivery by vacuum extraction.

Subgaleal hemorrhage is a rare condition of the neonate often associated with instrumental delivery. It is a potentially fatal condition that is often underreported and underdiagnosed. The vacuum extractor is being advocated as the instrument of first choice for assisted vaginal delivery, but appears to be associated with an increased incidence of subgaleal hemorrhage. It is widely believed that the vacuum cup will dislodge before causing serious fetal trauma. Because of the ease of application, vacuum extractors could be used potentially in circumstances in which forceps would not be attempted, allowing an operator of average experience to perform rotational deliveries. The worrisome increase in the incidence of subgaleal hemorrhage associated with vacuum extraction leads to the issuance of warnings from governmental authorities in Canada and the United States. This review discusses the anatomy of this lesion, etiology, clinical presentation, management, and possible prevention.

Birth Injuries↗
PubMed2003

Reduced expression of immunoreactive beta2-adrenergic receptor protein in human myometrium with labor.

A considerable body of evidence exists suggesting that the beta(2)-adrenergic receptor (beta(2)-AR) mediates uterine relaxation. However, little information exists on the localization, distribution, or expression of beta(2)-ARs in the human myometrium during the nonpregnant to labor transition. We have used immunochemical methods to investigate beta(2)-AR localization and expression in the nonpregnant, term pregnant, and term parturient uterus. Myometrial biopsies were obtained from 1) nonpregnant, menstruating women undergoing hysterectomy; 2) singleton term pregnant women undergoing elective cesarean section before the onset of labor; or 3) singleton term pregnant women undergoing emergency cesarean section after spontaneous labor. Tissues were processed for immunohistochemistry, immunofluorescence, and Western blotting and a primary polyclonal antibody specific to the human beta(2)-AR to identify immunoreactive myometrial beta(2)-AR. Protein levels were subsequently quantified by densitometry relative to rat brain protein. Immunohistochemistry and immunofluorescence demonstrated the presence of beta(2)-AR predominantly at the plasma membrane and also in the cytosol of myometrial cells. A 2-fold decrease in protein levels of the beta(2)-AR was apparent in the myometrium of labor compared with that of nonpregnant and pregnant nonlaboring women (P < 0.05). These results demonstrate that down-regulation of beta(2)-AR protein with labor may constitute a contributory mechanism by which uterine quiescence is removed at term.

Antibodies↗
PubMed2002

Infrared spectral features of exfoliated cervical cells, cervical adenocarcinoma tissue, and an adenocarcinoma cell line (SiSo).

OBJECTIVE: The objective of the present study is to evaluate and compare the infrared spectral features of normal and malignant exfoliated cervical cells, cells from malignant tissue, and the SiSo cell line. METHODS: Infrared spectra of cervical adenocarcinoma (CA) tissue, normal and malignant exfoliated cervical cells, and a uterine cervical adenocarcinoma cell line (SiSo) were obtained. Spectral qualities in terms of band intensity ratio and band position, which reflect configurational changes in the functional groups of the above samples, were measured. RESULTS: Spectral bands of CA tissue, exfoliated cells from CA, and the cell line were similar but markedly different from that of exfoliated normal cervical cells. Significant changes in bands at 1025 cm(-1) (glycogen), 1080 cm(-1) (glycogen and nucleic acids), 1155 cm(-1) (C-OH groups of serine, threonine, and tyrosine of cell proteins, and C-O groups of carbohydrates), 1240 cm(-1) (PO(2) groups of nucleic acids), 1400 cm(-1) (methyl group of lipids and proteins), and 1450 cm(-1) (methylene group of lipids and proteins) were noted in the CA tissue, exfoliated CA cells, and adenocarcinoma cell line compared with exfoliated normal cells. Marked shifts in band positions from 1080 to 1086 cm(-1), 1153 to 1160 cm(-1), and 935 to 970 cm(-1) in CA tissue, exfoliated CA cells, and the adenocarcinoma cell line were noted. CONCLUSION: Spectral bands of the adenocarcinoma cell line matched very well with those of cervical CA tissue and exfoliated CA cells in terms of position. In contrast, spectral bands of the SiSo cell line differed greatly from those of normal exfoliated cells.

Adenocarcinoma↗
PubMed2002

Clinical evaluation of a "hand pump" vacuum delivery device.

OBJECTIVE: To evaluate the clinical performance of a hand-held vacuum delivery system. METHODS: Between December 1999 and September 2000, a prospective audit was undertaken of all vacuum deliveries performed at Derby City General Hospital. RESULTS: In this period, 3296 deliveries occurred, of which 317 (9.6%) were by vacuum. Of these, data were collected on 300 (94.6%), 78 deliveries with the hand-held vacuum and 222 with standard vacuum. There were no differences in the demographic profiles, indication, gestational age at delivery, or birth weights between the two groups (P >.05 in all instances). In all types of delivery, nonrotational and rotational, the hand-held vacuum performed comparably to its contemporaries with no increase in delivery "failures" being noted. There were no differences in the extent or frequency of maternal injuries between the instruments, and other than transient scalp abrasions, there were no significant fetal injuries. CONCLUSION: The hand-held vacuum delivery system is a functionally effective addition to the practitioners' "armory," providing an alternative to the standard metal and silastic cups.

Adult↗
PubMed2002

Breech delivery.

Fetuses that present by the breech are at increased risk of trauma and hypoxia during delivery. The threshold for Caesarean section for breech presentation had been low for several years. The result of the term breech trial confirms that planned Caesarean section is the best method of delivering the singleton frank or complete breech at term. The best mode of delivery for the pre-term breech is less clear. Vaginal breech delivery will be unavoidable in certain circumstances and it is therefore important to be adept with the techniques of vaginal breech delivery. The atraumatic technique of delivery of the baby presenting by the breech at times of Caesarean section is similar to that of assisted vaginal breech delivery. The number of vaginal breech deliveries is falling, and regular teaching using video clips or practising with mannequins will be necessary to preserve the skills of vaginal breech delivery.

Breech Presentation↗
PubMed2000

CAESAREAN SECTION ON REQUEST.

Advances in surgical techniques, anaesthesia, thromboprophylaxis, blood transfusion, antibiotic therapy, and improved general health have changed Caesarean section (CS) from a procedure associated with considerable risk of morbidity and mortality to mother and/or fetus to one with little risk. Although CS is performed for obstetric indications, the threshold is lower, including CS on request, leading to a trend of rising CS rates. A main focus of debate is CS request by women who subjectively perceive benefit from an elective CS. The issues involved are complicated and the implications far-reaching. When risks, benefits, and costs are assessed, the perceived advantage of vaginal delivery over elective CS may be diminished or eliminated and decisions on the mode of delivery may be based on preferences rather than statistics. In this article, we outline some of the arguments for and against CS on request and the opinion of the Ethics Committee of the International Federation of Obstetricians and Gynaecologists (FIGO).

Journal Article↗