CONTINUOUS NON-INVASIVE ARTERIAL PRESSURE DEVICE AS AN ADJUNCT TO RECOGNIZE FLUCTUATING BLOOD PRESSURES DURING ELECTIVE CESAREAN SECTION UNDER SUBARACHNOID BLOCKADE (SAB).

BACKGROUND: Measuring non-invasive blood pressure (NIBP) in less than one minute intervals (STAT NIBP measurements) is not always feasible. Therefore, large number of undetectable hypotension episodes can only be recognized with continuous beat to beat monitoring of blood pressure, for example, by continuous non-invasive arterial pressure monitor (CNAP). OBJECTIVE: The purpose of the current study was to investigate whether CNAP correlates well with conventional intermittent oscillometric NIBP during elective cesarean sections under subarachnoid blockade (SAB) and whether CNAP based patient management results in improved immediate maternal vasopressor requirements and improved immediate fetal/neonatal outcomes compared with NIBP based patient management. MATERIALS AND METHODS: The CNAP finger cuff together with the CNAP arm cuff were placed on the same arm which also had the peripheral intravenous access.. On the contralateral arm the conventional NIBP arm cuff was placed. Study Group: The patients were managed by the anesthesia provider based on the CNAP monitor readings. Control Group: The patients were managed by the anesthesia provider based on the NIBP monitor readings. Results: The CNAP-based treatment (study) group had a statistically significant lower use of oxytocin and lower estimated blood loss than the NIBP-based treatment (control) group. The differences in incidences of vasopressors use and peri-operative nausea vomiting between study group and control group did not reach statistical significance. CNAP readings were more likely to be in systolic hypotensive phases (80mmHg) as compared to NIBP readings. CONCLUSION: Continuous non-invasive arterial pressure (CNAP) device may ONLY act as an adjunct to recognize fluctuating blood pressures during elective cesarean section under subarachnoid blockade (SAB).

Accidental dural puncture, postdural puncture headache, intrathecal catheters, and epidural blood patch: revisiting the old nemesis.

One of the controversial management options for accidental dural puncture in pregnant patients is the conversion of labor epidural analgesia to continuous spinal analgesia by threading the epidural catheter intrathecally. No clear consensus exists on how to best prevent severe headache from occurring after accidental dural puncture. To investigate whether the intrathecal placement of an epidural catheter following accidental dural puncture impacts the incidence of postdural puncture headache (PDPH) and the subsequent need for an epidural blood patch in parturients. A retrospective chart review of accidental dural puncture was performed at Hutzel Women's Hospital in Detroit, MI, USA for the years 2002-2010. Documented cases of accidental dural punctures (N = 238) were distributed into two groups based on their management: an intrathecal catheter (ITC) group in which the epidural catheter was inserted intrathecally and a non-intrathecal catheter (non-ITC) group that received the epidural catheter inserted at different levels of lumbar interspaces. The incidence of PDPH as well as the necessity for epidural blood patch was analyzed using two-tailed Fisher's exact test. In the non-ITC group, 99 (54 %) parturients developed PDPH in comparison to 20 (37 %) in the ITC [odds ratio (OR), 1.98; 95 % confidence interval (CI), 1.06-3.69; P = 0.03]. Fifty-seven (31 %) of 182 patients in the non-ITC group required an epidural blood patch (EBP) (data for 2 patients of 184 were missing). In contrast, 7 (13 %) of parturients in the ITC group required an EBP. The incidence of EBP was calculated in parturients who actually developed headache to be 57 of 99 (57 %) in the non-ITC group versus 7 of 20 (35 %) in the ITC group (OR, 2.52; 95 % CI, 0.92-6.68; P = 0.07). The insertion of an intrathecal catheter following accidental dural puncture decreases the incidence of PDPH but not the need for epidural blood patch in parturients.

Marked variability in peri-partum anesthetic management of patients on buprenorphine maintenance therapy (BMT): can there be an underlying acute opioid induced hyperalgesia precipitated by neuraxial opioids in BMT patients?

OBJECTIVES: To compare adequacy of peri-partum pain management with or without neuraxial opioids in patients on buprenorphine maintenance therapy (BMT). METHODS: After institutional review board approval for the study protocol, retrospective peripartum anesthesia/analgesia data of BMT patients for five-year period were accessed and analyzed. RESULTS: Out of reviewed 51 patient charts, nineteen patients were found eligible for final comparative analysis. The daily amounts of peri-partum rescue analgesics with vs without neuraxial opioids were equianalgesic doses of parenteral hydromorphone (10.7 +/- 13.8 mg vs 2.6 +/- 0.7 mg, P = 0.45 for vaginal delivery; 16.4 +/- 21.1 mg vs 5.3 +/- 3.6 mg, P = 0.42 for elective cesarean section (CS)), oral ibuprofen (1.1 +/- 0.5g vs 0.8 +/- 0.4g, P = 0.37 for vaginal delivery; 1.1 +/- 0.2g vs 1.6 +/- 0.6g, P = 0.29 for elective CS), and acetaminophen (0.2 +/- 0.4g vs 0 +/- 0g, P = 0.56 for vaginal delivery; 0.3 +/- 0.3g vs 0.2 +/- 0.2g, P = 0.81 for elective CS). In the patients who underwent emergent CS after failed labor (all had received epidural opioids), there was clinical trend for higher daily amounts ofperi-partum rescue analgesics (parenteral hydromorphone 35.6 +/- 37.5 mg; oral ibuprofen 1.2 +/- 0.4g; oral acetaminophen 1.2 +/- 0.5g), when compared with vaginal delivery patients or elective CS patients who all had received neuraxial opioids. CONCLUSIONS: As the study was underpowered (n = 19), future adequately powered studies are required to conclude for-or-against the use ofneuraxial opioids in BMT patients; and pro-nociceptive activation by neuraxial opioids may be worth investigating to improve our understanding of peripartum pain management of BMT patients.

Dural puncture epidural analgesia is not superior to continuous labor epidural analgesia.

BACKGROUND: Some anesthesiologists consider combined spinal epidural (CSE) analgesia as superior alternative to continuous labor epidural (CLE) analgesia. However, during CSE, even small doses of intrathecally administered local anesthetics with opioids induce almost instant analgesia that precludes the testing of epidural catheters as well as early appreciation of failed epidural catheters. To overcome the shortcomings of CSE analgesia, dural puncture epidural (DPE) analgesia had been devised. OBJECTIVES: The goals for the present study were to test whether DPE technique would provide superior and safer labor analgesia as compared to CLE technique. MATERIALS AND METHODS: 131 ASA Class I, II and III pregnant patients who requested labor epidural analgesia consented for their participation in this prospective randomized study. Group A patients received CLE analgesia for labor pain. Group B patients received DPE analgesia for labor pain. RESULTS: After exclusion of nineteen patients, final comparative data was available for 112 patients only [Group A (n = 63) versus Group B (n = 49)]. Per our analysis, the only positive aspect for DPE analgesia as compared to CLE analgesia was that patients who received DPE analgesia reported lower incidence for immediate failures of labor analgesia (P = 0.04). However, there was higher incidence of paresthesias while performing successful dural punctures (P < 0.0001). Pre-insertion epidural depth assessment with ultrasound (n = 112) correlated positively with the air-filled loss of resistance syringe technique (r = 0.88; P < 0.0001). CONCLUSION: DPE technique did not provide superior labor analgesia as compared to CLE technique. Technically, fewer immediate failures in labor analgesia but higher incidence of paresthesias were observed with DPE technique.

Predictive model for the inadequate labor epidural analgesia: an outcome of the prospective observational study at university women's hospital.

BACKGROUND: Continuous epidural analgesic infusions provide superior analgesia as compared to other forms of labor analgesia. However, inadequate analgesia after labor epidurals is not uncommon and has been found to be as high as 24% in some studies. The mechanism of these failures include inappropriate epidural catheter location, tissue compartmentalization within epidural space, delayed migration, kinking, occlusion or disconnection of correctly placed epidural catheter. AIMS: The aim of our study was to examine the effect of various factors on the incidence of inadequate pain relief with labor epidurals. METHODS: Eighteen independent potential risk factors for failed epidurals were collected from each parturient: patient characteristics (body mass index, history of failed epidural, opioid tolerance, illicit drug use and back abnormalities), labor details (parity, singleton versus multiples pregnancies, induced versus spontaneous labor, augmentation with oxytocin, malpresentation and cervical dilatation greater than 7 cm), epidural technique (experience of the operator-resident/specialist, method of loss of resistance-air/saline, paresthesia during epidural insertion, difficult insertion, ultrasound used, and number of attempts) and other factors (time of epidural insertion). RESULTS: Data collected from 502 parturients showed that difficulty in placement of epidural catheter was reported in 43 (8.6%) patients. Inadequate pain reliefwas seen in 104 (21%) parturients. Cervical dilatation > 7 cm, previous failed epidural analgesia, paresthesia during epidural insertion, and loss of resistance using air were found to be the best predictors of inadequate epidural analgesia A constructed classification table showed that the predictive model correctly classified 96.7% of successful epidurals of producing adequate pain relief. However, the predictive model correctly classified only eighteen failed/inadequate epidurals (16.8%) as failures. Overall, 79.7% of the epidurals placed were successfully classified by the predictive model. CONCLUSION: In parturients identified as being at high risk for failed epidural, ultrasound guidance, saline-based loss of resistance technique, and appropriate intra-epidural-space length of catheter are the methods that should be utilized to lower the incidence of failure.