A century of regional analgesia in obstetrics

Ultrasound-Guided Neuraxial Anesthesia

PURPOSE OF REVIEW

There has been a recent surge of interest in clinical applications of ultrasound, which has revolutionized acute pain management. This review is to summarize the current status of ultrasound utilization in neuraxial anesthesia, the most common type of regional anesthesia.

RECENT FINDINGS

Ultrasound-assisted and ultrasound-guided neuraxial anesthesia has improved clinical accuracy and patient safety through landmark identification including proper vertebral level and midline, as well as via measurements on neuraxial space. Direct needle or catheter visualization during the entire procedure has not yet been achieved consistently. The recent introduction of ultrasound into neural anesthesia has clinical performance benefits and patient safety implications, with documented improvement on overall efficacy with higher first attempt success rate as well as less needle pass. More controlled studies are needed for the overall impact of ultrasonography in neuraxial anesthesia in obstetric and non-obstetric patients.

Pain Management in Obstetrics

Critical care clinicians may be called on to care for a laboring woman. Comprehension of the anatomic changes associated with pregnancy, and labor and birth, is essential. A working knowledge of the current options for pain management in labor, both pharmacologic and nonpharmacologic, is necessary to facilitate patient-centered care. Pharmacologic options include intravenous or intramuscular agents, inhalational agents, and neuraxial anesthesia. Each modality has contraindications, risks, and benefits that must be considered when choosing the most appropriate method.

Estimation of Skin to Subarachnoid Space Depth: An Observational Study

INTRODUCTION

In a patient, the skin to Subarachnoid Space Depth (SSD) varies considerably at different levels of the spinal cord. It also varies from patient to patient at the same vertebral level as per age, sex and Body Mass Index (BMI). Estimation of the skin to SSD reduces complications related to spinal anaesthesia.

AIM

To measure the skin to SSD in the Indian population and to find a formula for predicting this depth.

MATERIALS AND METHODS

Three hundred adult patients belonging to American Society of Anaesthesiologist class I and II, undergoing surgery using spinal anaesthesia in various surgical specialities of Gauhati Medical College were selected by systemic sampling for this prospective, observational study. Patients were divided into three groups: Group M containing male patients, Group F containing non-pregnant female patients, and Group PF containing pregnant female's patients. SSD was measured after performing lumbar puncture. The relationship between SSD and patient characteristics were studied, correlated and statistical analysis was used to find a formula for predicting the skin to SSD. Statistical analysis was done using Statistical Package for Social Sciences (SPSS 21.0, Chicago, IL, USA). One-way ANOVA with post-hoc(Bonferroni correction factor) analysis was applied to compare the three groups. Multivariate analysis was done for the covariates followed by a multivariate regression analysis to evaluate the covariates influencing SSD for each group separately.

RESULTS

Mean SSD was 4.37±0.31cm in the overall population. SSD in adult males was 4.49±0.19cm which was significantly longer than that observed in female's 4.18±0.39cm which was comparable with SSD in parturient 4.43±0.19 cm. The formula for predicting the skin to SSD in the male population was 1.718+0.077×BMI+0.632×Height, in nonpregnant female population was 1.828+0.077×BMI+0.018×Height+0.007×Age and 0.748+0.209×BMI+4.703×Height-0.054×weight in parturient females, respectively.

CONCLUSION

Skin to SSD correlated with the BMI in all the patients in our study.

Analgesia for childbirth: modern insights into an age-old challenge and the quest for an ideal approach

SUMMARY It is widely recognized that childbirth may be the most painful experience in a woman’s lifetime and that women have a right to relief. There are many options, but the efficacy of only a few is supported by robust evidence. Many influences determine which method of pain relief is chosen, including social and cultural factors, availability, cost and personal preference. Due to human diversity and the differing perspectives of consumers, obstetric care providers and health administrators, there is no such thing as ‘an ideal approach’. In resource-rich societies, major advances in parturient safety and outcome flow from technique development and better monitoring. Greater awareness of the negative impact of untreated pain and of the relevance of genetic, cultural and social factors motivates research into better predictive models, novel therapies and optimization of existing methods.

[A look into the past: improves in obstetrical and neonatal outcome in maternity since the 19th century]

OBJECTIVE

Evaluate changes in obstetrical and neonatal outcome of women who delivered in maternity hospital since the 19(th) century.

MATERIALS AND METHODS

Data from a historic cohort of 1022 women who delivered between 1871 and 1874 in the hôtel Dieu hospital of Marseille were compared to those from 1159 women who delivered from 2005 to 2006 in the level 3 maternity of Nord hospital of Marseille (contemporary cohort). Deliveries that had occured before 22 weeks and/or with a foetal birth weight of less than 500 g were excluded.

RESULTS

A total of 2131 pregnancies were included: 1011 and 1120 in historic and contemporary cohort, respectively. Despite comparable mean term of delivery, mean birth weight of neonates from historic cohort were significantly lower: 2971 g (550-4900 g) vs 3250 g (500-5375 g), respectively (p<0.001). Stillbirths were reported in 72 (7.1%) cases in historic cohort compared to nine (0.8%) in contemporary cohort (p<0.001). Neonatal mortality was 3.7% in historic cohort and 1.9% in contemporary cohort (p=0.012). A total of 99 (9.8%) maternal deaths were reported in historic cohort, while none in contemporary cohort (p<0.001). A wide majority of maternal deaths were caused by maternal infection (72.9%); 5.2% were caused by postpartum haemorrhage.

CONCLUSION

Our results illustrate the tremendous impact on maternal and neonatal outcome of advances in obstetrical management. The significant increase in the median foetal birth weight is likely to be related to wide changes in environmental conditions and behaviour.

[Management of cardiac high risk pregnancy. Caesarean section in a primagravida with cyanotic cardiac defect]

A 37-year-old gravida I with cyanotic heart disease presented for caesarean section in the 31st week of gestation. Caesarean section was performed uneventfully with the patient under epidural anaesthesia accompanied by invasive monitoring. Postoperative echocardiography showed no change in the shunt fraction, volumes or the ventricular function. Every patient with complex comorbidities has to be managed according to individual prerequisites and the experiences and preferences of the team. For such high risk pregnancies regional anaesthesia seems to be a possible option although no clear evidence can be found in the literature.

The historical narrative: tales of professionalism?

The historical narrative is a story told to illustrate a point, however subconsciously. The "giants" of obstetric anesthesia -- Simpson, Snow, Apgar -- and countless other less well-known physicians all contributed to the history of obstetric anesthesia. We remember them by retelling this history to illustrate elements of professionalism and how we as a profession wish to act. The Physician Charter is an excellent first approximation of a workable definition of this quality, which can and does change over time. By using the three principles and 10 professional responsibilities as a template, the past comes alive as a teaching method to each and every obstetric anesthesiologist.

Post dural puncture headache in obstetric patients: experience from a West African teaching hospital

BACKGROUND

This prospective, non-randomised study examined the frequency and severity of post dural puncture headache in 96 Ghanaian women who consented to spinal anaesthesia for caesarean section at the Korle Bu Teaching Hospital, Accra, Ghana.

METHOD

Spinal anaesthesia was performed using 22-gauge (n = 22), 25-gauge (n = 46) or 26-gauge (n = 38) Quincke needles. Patients were followed up to determine the incidence and severity of post spinal headache.

RESULT

The overall incidence of post dural puncture headache was 8.3%, but was significantly higher (33%) in patients in whom 22-gauge Quincke needles were used than in the other two groups (4% and 5% respectively: P = 0.003). Most patients rated their headache as mild to moderate on a 10-cm visual analogue scale.

CONCLUSIONS

In view of the high incidence of headache and the need for treatment associated with the use of the 22-gauge Quincke needle, we recommend that this should not be used in the obstetric population. We are also aware that the incidence of post dural puncture headache could be further reduced by the use of small calibre pencil-point needles but these are currently very expensive and many obstetric units in developing countries may not be able to afford them.

Analgesia and Anesthesia in Labor

Whether given as an epidural, spinal, or combination, regional anesthesia is an integral part of obstetrics in the United States. A variety of drugs and dosages are used in various combinations, with no one protocol exceeding others in terms of efficacy and safety. The availability of anesthesia and analgesia has had an extraordinary impact on the field of obstetrics in the twentieth century. Knowledge of the techniques and medications used, their potential toxicities, and effects on the labor process itself can only enhance obstetricians' management of the parturient in labor.

Obstetric anesthesia: changes and choices

This article is a review of analgesics and anesthetics offered to laboring women, including intravenous drugs, epidural and spinal agents, and inhalational anesthetics. An overview of the uses, risks, and benefits is provided for each anesthetic alternative. To provide the most effective care to women in labor, clinicians have a responsibility to have current knowledge of the best evidence for safety and efficacy of these pharmacologic agents and techniques and be able to effectively communicate this information to clients.

Post-dural puncture headache: pathogenesis, prevention and treatment

Spinal anaesthesia developed in the late 1800s with the work of Wynter, Quincke and Corning. However, it was the German surgeon, Karl August Bier in 1898, who probably gave the first spinal anaesthetic. Bier also gained first-hand experience of the disabling headache related to dural puncture. He correctly surmised that the headache was related to excessive loss of cerebrospinal fluid (CSF). In the last 50 yr, the development of fine-gauge spinal needles and needle tip modification, has enabled a significant reduction in the incidence of post-dural puncture headache. Though it is clear that reducing the size of the dural perforation reduces the loss of CSF, there are many areas regarding the pathogenesis, treatment and prevention of post-dural puncture headache that remain contentious. How does the microscopic pattern of collagen alignment in the spinal dura affect the dimensions of the dural perforation? How do needle design, size and orientation influence leakage of CSF through the dural perforation? Can pharmacological methods reduce the symptoms of post-dural puncture headache? By which mechanism does the epidural blood patch cure headache? Is there a role for the prophylactic epidural blood patch? Do epidural saline, dextran, opioids and tissue glues reduce the rate of CSF loss? This review considers these contentious aspects of post-dural puncture headache.

Analgesia and Anesthesia During Labor and Birth: Implications for Mother and Fetus

Labor and birth, although viewed as a normal physiological process, can produce significant pain, requiring appropriate pain management. Systemic analgesia and regional analgesia/anesthesia have become less common, whereas the use of newer neuraxial techniques, with minimal motor blockade, have become more popular. Low- and ultra-low-dose epidural analgesia, spinal analgesia, and combination spinal-epidural analgesia have replaced the once traditional epidural for labor. The shift from regional anesthesia during labor, in which the woman became a passive participant during the labor and birth, to a collaborative approach for pain management, in which the woman becomes an active participant, has resulted in a new philosophy of labor analgesia. This article provides a review of the current systemic analgesics and regional and neuraxial analgesia/anesthesia techniques for pain management in labor and birth. Also addressed are implications for perinatal nurses who participate in pain management choices during labor and birth.

Neuraxial analgesia for labor and birth: implications for mother and fetus

Women are better educated today on issues related to labor and childbirth. Pain management options for the woman in labor have changed dramatically over the last decade. Systemic analgesia and dense-motor-blockade regional analgesia/anesthesia have become less common for childbirth while the use of newer neuraxial and regional techniques, with minimal motor blockade, have become more popular. The shift from regional anesthesia with significant motor-blockade during labor, where the woman is a passive participant during the labor and birth, to a collaborative approach for pain management, where the woman becomes an active participant, has resulted in a new philosophy of analgesia for labor and birth. This article provides a review of current neuraxial analgesia/anesthesia techniques used for pain management in labor and birth and their implications for the perinatal nurse.