Just Published Epidural Anesthesia Research

Lidocaine inhibits NIH-3T3 cell multiplication by increasing the expression of cyclin-dependent kinase inhibitor 1A (p21).

Lidocaine inhibits NIH-3T3 cell multiplication by increasing the expression of cyclin-dependent kinase inhibitor 1A (p21).

Anesth Analg. 2008 Nov;107(5):1592-7

Authors: Desai SP, Kojima K, Vacanti CA, Kodama S

BACKGROUND: We explored molecular mechanisms by which lidocaine inhibits growth in the murine embryonic fibroblast cell line NIH-3T3. Local anesthetics can adversely affect cell growth in vitro. Their effects on wound healing are controversial. We examined the effects and novel mechanisms by which lidocaine affects in vitro multiplication of the murine fibroblast cell line NIH-3T3. METHODS: NIH-3T3 cells were grown in culture with lidocaine [0, 0.05, 0.5, 1, 2, and 5 mM]. Cell multiplication was assessed by determining cell counts on subsequent days, while mechanisms by which inhibition occurred were evaluated by bromodeoxyuridine uptake, gene expression using polymerase chain reaction array, and Western blot analysis to verify increased levels of affected proteins. RESULTS: Lidocaine caused dose-dependent inhibition of multiplication of NIH-3T3 cells. Effects ranged from no inhibition [0.05 and 0.5 mM] and mild inhibition [1 mM], to severe inhibition [2 and 5 mM] [P = 0.006]. Lidocaine 2 mM inhibited bromodeoxyuridine uptake at day 3.5 [P = 0.02 versus control, and P = 0.0495 vs 1 mM lidocaine]. On day 1.5, lidocaine upregulated expression of cyclin-D1 and cyclin-dependent kinase inhibitor 1A [p21]. On day 2.5, lidocaine increased the levels of p21 protein. CONCLUSIONS: Low concentrations of lidocaine, as would be seen in plasma after spinal, epidural, or plexus anesthesia, do not significantly affect multiplication of fibroblasts. Higher doses of lidocaine arrest cell multiplication at the S-phase of the growth cycle by upregulation of p21, an extremely potent inhibitor of cell multiplication. Higher concentrations, as would be seen after tissue infiltration, severely inhibit fibroblast multiplication and thus may impair wound healing.

PMID: 18931217 [PubMed - indexed for MEDLINE]

Plethysmographic pulse wave amplitude is an effective indicator for intravascular injection of epinephrine-containing epidural test dose in sevoflurane-anesthetized pediatric patients.

Plethysmographic pulse wave amplitude is an effective indicator for intravascular injection of epinephrine-containing epidural test dose in sevoflurane-anesthetized pediatric patients.

Anesth Analg. 2008 Nov;107(5):1536-41

Authors: Mowafi HA, Arab SA, Ismail SA, Al-Ghamdi AA, Al-Metwalli RR

BACKGROUND: Plethysmographic pulse wave amplitude (PPWA) was effective in detecting intravascular injection of epidural test dose with 100% sensitivity and specificity in adults. We evaluated the efficacy of PPWA in detecting intravascular injection of a simulated epidural test dose during sevoflurane anesthesia in pediatric patients. METHODS: Eighty infants and children were randomized to receive either 0.5 minimal alveolar concentration (MAC) or 1 MAC sevoflurane and nitrous oxide in oxygen. Patients in each anesthesia group were further randomized to receive either 0.1 mL/kg of 1% lidocaine with 1:200,000 epinephrine (0.5 mug/kg of epinephrine) IV to simulate the intravascular injection of epidural test dose or saline. Heart rate (HR), systolic blood pressure (SBP), and PPWA were monitored for 5 min after injection. A positive test response was defined as HR increase > or =10 bpm, SBP increase > or =15 mm Hg, and PPWA decrease > or =10%. RESULTS: Injecting the test dose resulted in an average maximum PPWA decrease by 69% +/- 18% and 58% +/- 14% at 79 +/- 22 and 80 +/- 19 s in the 0.5 MAC and 1 MAC sevoflurane groups, respectively. The sensitivity, specificity, positive predictive, and negative predictive values for PPWA were 100% in both sevoflurane groups, whereas by using HR and SBP criteria, the sensitivity was 90% and 95% respectively during 0.5 MAC sevoflurane anesthesia and 85% for both during 1 MAC sevoflurane anesthesia. CONCLUSION: PPWA is effective for detection of an intravascular injection of a simulated epidural epinephrine-containing test dose in pediatric patients.

PMID: 18931211 [PubMed - indexed for MEDLINE]

Hyperventilation-induced hypocapnia changes the pattern of electroencephalographic bicoherence growth during sevoflurane anaesthesia.

Hyperventilation-induced hypocapnia changes the pattern of electroencephalographic bicoherence growth during sevoflurane anaesthesia.

Br J Anaesth. 2008 Nov;101(5):666-72

Authors: Hayashi K, Fujikawa M, Sawa T

BACKGROUND: Hyperventilation, with the resulting hypocapnia, reduces cerebral blood flow and causes slowing of the EEG activity. However, neuronal oscillating properties including the thalamocortical network during hyperventilation have not been elucidated. To assess these features provoked by hyperventilation, the present study examined quadratic phase coupling features by means of bicoherence analysis. METHODS: Twenty-two patients were anaesthetized using sevoflurane 1.5% combined with remifentanil or epidural anaesthesia. After a stable normocapnic period, hypocapnia was induced by hyperventilation, and the raw EEG signals were collected. Bispectral analysis (bicoherence) and power spectrum analysis were performed before and after hypocapnia. RESULTS: Mean (sd) peak bicoherence in the delta- area increased from 35.6 (10.9)% during normocapnia to 43.8 (10.9)% during hypocapnia (P<0.05), whereas mean (sd) peak bicoherence in the alpha area decreased from 42.8 (14.4)% during normocapnia to 37.5 (12.3)% during hypocapnia (P<0.05). Normalized power in the delta- frequencies on the power spectrum increased from 60.2 (13.1)% to 72.5 (12.7)% (P<0.05). Bispectral index and spectral edge frequency changed from 45.9 (7.0) to 40.1 (5.6) (P<0.05) and from 15.0 (2.3) to 14.0 (2.5) Hz (P<0.05), respectively. No significant differences in these values were observed between the two types of anaesthesia. CONCLUSIONS: Hypocapnia enlarged bicoherence growth in the delta- frequency range, suggesting the contribution of subcortical oscillating mechanisms in regulating EEG during hyperventilation.

PMID: 18791187 [PubMed - indexed for MEDLINE]

Review Article: Multiple Sclerosis and Reproductive Risks in Women.

Review Article: Multiple Sclerosis and Reproductive Risks in Women.

Reprod Sci. 2008 Oct;15(8):755-764

Authors: Argyriou AA, Makris N

During the previous decades, women with Multiple Sclerosis (MS) were discouraged from having children, as pregnancy was deemed dangerous for pregnancy outcome and a contributing factor for exacerbation of MS. Current knowledge shows that women with MS are no more likely to have pregnancy or delivery complications compared to healthy women. Immunomodulatory therapies should be avoided during pregnancy and while breastfeeding. However, despite that it is still not recommended during pregnancy, Glatiramer acetate has fewer risks than the other MS drugs with respect to pregnancy outcome. IVIg treatment appears to be safe in unblinded studies and may be used after the first trimester to prevent the exacerbation of postpartum relapses. Gestation is a period of decreased risk for a relapse, whereas relapses are more common in the first six months after childbirth, compared to the pre-pregnancy period. Breastfeeding and epidural anaesthesia are not associated with increased incidence of post-partum relapses.

PMID: 19017813 [PubMed - as supplied by publisher]

[Coronary artery bypass grafting in conscious patients : A procedure with a perspective?]

[Coronary artery bypass grafting in conscious patients : A procedure with a perspective?]

Anaesthesist. 2008 Nov 19;

Authors: Byhahn C, Meininger D, Kessler P

Patients undergoing coronary artery bypass grafting increasingly show severe co-morbidities, which can negatively affect the outcome. Recent developments in cardiac surgery have therefore focused on minimizing the invasiveness of the procedure by revascularization on the beating heart without cardiopulmonary bypass, and by reducing surgical trauma using smaller surgical incisions. Progress in minimally invasive cardiac surgery has led to minimally invasive anesthesia, i.e. using high thoracic epidural anesthesia as the sole technique in the conscious patient (awake coronary artery bypass grafting, ACAB). Published data on ACAB procedures in smaller cohorts have demonstrated that the procedure is safe. Significant complications occurred in 7.1% of patients. A particular cause of concern during ACAB surgery is the development of spinal epidural hematoma the risk of which has been estimated to be as high as 1:1,000. A thorough risk-benefit analysis has therefore to be made. Currently, ACAB surgery remains limited to few specialized centers and highly selected patients.

PMID: 19015830 [PubMed - as supplied by publisher]

A randomized trial of dural puncture epidural technique compared with the standard epidural technique for labor analgesia.

A randomized trial of dural puncture epidural technique compared with the standard epidural technique for labor analgesia.

Anesth Analg. 2008 Nov;107(5):1646-51

Authors: Cappiello E, O'Rourke N, Segal S, Tsen LC

BACKGROUND: We designed this prospective, double-blind, randomized study to examine whether a dural puncture without intrathecal drug administration immediately before epidural drug administration would improve labor analgesia when compared to a traditional epidural technique without prior dural puncture. METHODS: Eighty nulliparous parturients with cervical dilation less than 5 cm were randomly assigned to receive a standardized epidural technique, with or without a single dural puncture with a 25-gauge (G) Whitacre spinal needle. After successful placement of the needle(s) and the epidural catheter, 12 mL of bupivacaine 2.5 mg/mL was administered through the epidural catheter and a patient-controlled epidural infusion of bupivacaine 1.25 mg/mL + fentanyl 2 mug/mL was initiated. The presence of sacral analgesia (S1) and pain scores were compared between groups. RESULTS: In demographically similar groups, parturients with prior dural puncture had more frequent blockade of the S1 dermatome (absolute risk difference [95% confidence interval] 22% [6-39]), more frequent visual analog scale scores <10/100 at 20 min (absolute risk difference 20% [1-38]), and reduced one-sided analgesia (absolute risk difference [95% CI] 17% [2-330]). The highest median sensory level (T10) was no different between groups. CONCLUSIONS: Dural puncture with a 25-G spinal needle immediately before the initiation of epidural analgesia improves the sacral spread, onset, and bilateral pain relief produced by analgesic concentrations of bupivacaine with fentanyl in laboring nulliparous patients.

PMID: 18931227 [PubMed - indexed for MEDLINE]