Saadia S. Sherwani

Efficacy of a prophylactic epidural blood patch in preventing post dural puncture headache in parturients after inadvertent dural puncture.

Background:Postdural puncture headache (PDPH) occurs in up to 80% of parturients who experience inadvertent dural puncture during epidural catheter placement. The authors performed a randomized double blind study to assess the effect of prophylactic epidural blood patch on the incidence of PDPH and the need for therapeutic epidural blood patch. Methods:Sixty-four parturients who incurred inadvertent dural puncture were randomized to receive a prophylactic epidural blood patch with 20 ml autologous blood (prophylactic epidural blood patch group) or a sham patch (sham group). Subjects were evaluated daily for development of PDPH for a minimum of 5 days after dural puncture. Those who developed a PDPH were followed daily for a minimum of 3 days after resolution of the headache. Subjects with moderate headaches who reported difficulties performing childcare activities and all those with severe headaches were advised to receive a therapeutic epidural blood patch. Results:Eighteen of 32 subjects in each group (56%) developed PDPH. Therapeutic blood patch was recommended in similar numbers of patients in each group. The groups had similar onset time of PDPH, median peak pain scores, and number of days spent unable to perform childcare activities as a result of postural headache. The median duration of PDPH, however, was shorter in the prophylactic epidural blood patch group. Conclusions:A decrease in the incidence of PDPH or the need for criteria-directed therapeutic epidural patch was not detected when a prophylactic epidural blood patch was administered to parturients after inadvertent dural puncture. However, prophylactic epidural blood patch did shorten the duration of PDPH symptoms.

Intraoperative pulmonary embolism and intracardiac thrombosis complicating liver transplantation: a systematic review

Summary.  Background: Pulmonary embolism (PE) and intracardiac thrombosis (ICT) are rare but potentially lethal complications during orthotopic liver transplantation (OLT). Methods: We aimed to review clinical and pathological correlates of PE and ICT in patients undergoing OLT. A systematic review of the literature was conducted using MEDLINE and ISI Web of Science. Results: Seventy‐four cases of intraoperative PE and/or ICT were identified; PE alone in 32 patients (43%) and a combination of PE and ICT in 42 patients (57%). Most frequent clinical symptoms included systemic hypotension and concomitant rising pulmonary artery pressure, often leading to complete circulatory collapse. PE and ICT occurred in every stage of the operation and were reported equally in patients with or without the use of venovenous bypass or antifibrinolytics. A large variety of putative risk factors have been suggested in the literature, including the use of pulmonary artery catheters or certain blood products. Nineteen patients underwent urgent thrombectomy or thrombolysis. Overall mortality was 68% (50/74) and 41 patients (82%) died intraoperatively. Conclusion: Mortality was significantly higher in patients with an isolated PE, compared to patients with a combination of PE and ICT (91% and 50%, respectively; P < 0.001). Intraoperative PE and ICT during OLT appear to have multiple etiologies and may occur unexpectedly at any time during the procedure.

Small-dose dexamethasone improves quality of recovery scores after elective cardiac surgery: a randomized, double-blind, placebo-controlled study.

OBJECTIVES The use of steroid therapy in cardiac surgical patients remains controversial. The aim of this clinical investigation was to determine the effect of small-dose dexamethasone therapy on patient-perceived quality of recovery (QoR) scores in elective cardiac surgical patients. In addition, the authors assessed the impact of dexamethasone on the incidence of common adverse events after cardiopulmonary bypass (CPB). DESIGN A prospective, randomized study. SETTING University hospitals. PARTICIPANTS One hundred seventeen patients undergoing cardiac surgery with CPB and anticipated early tracheal extubation. INTERVENTIONS Subjects were randomized to receive either dexamethasone (dexamethasone group, 8 mg at the induction of anesthesia and at the initiation of CPB) or placebo (control group, saline). MEASUREMENTS AND MAIN RESULTS The QoR was assessed using the QoR-40 scoring system preoperatively and on postoperative days (PODs) 1 and 2. Secondary outcome measures assessed in the postoperative period included nausea, vomiting, fatigue, febrile responses, shivering, pulmonary gas exchange, and analgesic requirements. Global QoR-40 scores (median [range]) were higher in the dexamethasone group compared with the control group on POD 1 (167 [133-192] v 157 [108-195]; p < 0.0001) and POD 2 (173 [140-196] v 166 [122-196]; p = 0.001). In the dexamethasone group, improved QoR was observed in the QoR-40 dimensions of emotional state (p = 0.002), physical comfort (p = 0.0001-0.006), and pain (p < 0.0001). The incidences or severity of postoperative fatigue (p < 0.0001), febrile responses (p < 0.0001), and shivering (p = 0.001) were reduced in the dexamethasone group. CONCLUSIONS Patient-perceived postoperative QoR in cardiac surgical patients is enhanced significantly by small-dose dexamethasone treatment.

Systemic magnesium to reduce postoperative arrhythmias after coronary artery bypass graft surgery: A meta-analysis of randomized controlled trials

OBJECTIVE To evaluate the effect of systemic magnesium on the prevention of postoperative cardiac arrhythmias after coronary artery bypass graft surgery. DESIGN A meta-analysis. SETTING Randomized controlled trials evaluating the effect of systemic magnesium on the incidence of postoperative arrhythmias. PARTICIPANTS Patients undergoing coronary artery bypass graft surgery. INTERVENTIONS Systemic perioperative administration of magnesium sulfate. MEASUREMENTS AND MAIN RESULTS Twenty studies evaluating 3,696 subjects were included. The combined effect suggested that systemic magnesium reduced the incidence of supraventricular arrhythmias compared with saline (odds ratio [OR] = 0.69; 95% confidence interval [CI], 0.53-0.90; number needed to treat [NNT] = 14). The effect was present for lower-quality studies (Jadad score ≤3; OR = 0.47; 95% CI, 0.28-0.81; NNT = 8), but it was not detected for higher-quality studies (Jadad >3; OR = 0.85; 95% CI, 0.66-1.11). There was no association between the total dose of magnesium administration and the incidence of supraventricular arrhythmias (p = 0.19). There was no effect of magnesium on the incidence of postoperative stroke, myocardial infarction, and death. In addition, magnesium did not reduce the hospital or intensive care unit lengths of stay (all p > 0.05). CONCLUSIONS The effect of magnesium sulfate in reducing postoperative supraventricular arrhythmias was significant when examined by lower-quality studies but not when examined by higher-quality studies. This fact probably is responsible for controversial findings reported in the literature. Also, magnesium sulfate did not reduce the incidence of complications associated with the development of postoperative cardiac arrhythmias. More effective strategies should be used to prevent complications caused by arrhythmias in this patient population.

The successful use of low-dose recombinant tissue plasminogen activator for treatment of intracardiac/pulmonary thrombosis during liver transplantation

Intracardiac thrombosis and pulmonary embolism are uncommon complications during liver transplantation but carry a high mortality rate. We report the successful use of low-dose recombinant tissue plasminogen activator (0.5-4 mg) administration in 4 patients. Early diagnosis through transesophageal echocardiography and pulmonary artery catheterization may have contributed to the rapid thrombolysis.

United States Practice Patterns in the Use of Transesophageal Echocardiography During Adult Liver Transplantation

OBJECTIVE To characterize contemporary practice patterns in the use of transesophageal echocardiography during adult liver transplantation and to identify factors preventing more frequent use. DESIGN Online questionnaire. SETTING Liver transplantation centers in the United States performing 12 or more adult liver transplants in 2011. PARTICIPANTS One representative from each qualifying center: The transplant anesthesiology director, a transplant anesthesiologist personally known to the authors, or the department of anesthesiology chair. INTERVENTIONS Three e-mail attempts were made to solicit participation in the study between June and August 2012. MEASUREMENTS AND MAIN RESULTS Of the 97 institutions identified, an anesthesiologist from each of 79 (81.4%) centers completed the questionnaire; 38.0% of centers reported routine use and 57.0% for special circumstances or rescue situations, yielding an overall use rate of 94.9%. This distribution was consistent regardless of operative volume, practice size, or academic affiliation. The sole factor predictive of routine transesophageal echocardiography use was an overlap between an institutions cardiac and transplant anesthesiology teams. In practices not routinely employing the technology, the most compelling reason was a sense that it was not necessary. Although 69.9% of transplant anesthesiologists reportedly were proficient in echocardiography, inadequate anesthesiologist training was also a strongly cited hindrance. CONCLUSIONS Transesophageal echocardiography during adult liver transplantation in the United States has become widely prevalent, with notable growth in its use as a routine diagnostic and monitoring modality. Almost all institutions now use the technology at least occasionally, with the participation of cardiac anesthesiologists being predictive of a centers routine use.

The use of transesophageal echocardiography for confirmation of appropriate impella 5.0 device placement

CASE PRESENTATION A 44-year-old man was admitted to our institution in cardiogenic shock. He was previously healthy but presented with several days of increasing fatigue and dyspnea. Eventually, a diagnosis of giant cell myocarditis was made via endomyocardial biopsy. Once admitted, an intraaortic balloon pump (IABP) was placed for circulatory support. Subsequent hemodynamic deterioration required placement of the TandemHeart (Cardiac Assist, Inc., Pittsburgh, PA) to support right-sided circulation. As a bridge to biventricular assist device placement, the decision was made to replace the IABP with an Impella Recover LP 5.0 (Abiomed, Inc., Danvers, MA) (“Impella”). Anesthesia was induced in the operating room, and a transesophageal echocardiography (TEE) probe was placed for monitoring. Intraoperative TEE confirmed severe hypokinesis of the left ventricle (LV), right ventricular dilation, and severely reduced right ventricular function. Two TandemHeart cannulas were noted: the inflow cannula in the right atrium, and the outflow cannula passing through the right atrium and ventricle into the pulmonary artery. This cannula configuration, different from the originally described use of the TandemHeart as an LV support device, has been effective in supporting right-sided circulation. There were no major valvular abnormalities. An IABP was visible in the descending aorta. After gaining access to the right common femoral artery, the IABP was removed and replaced with an introducer sheath by the surgeon. A wire was advanced across the aortic valve (AV), and the Impella was advanced through the sheath and into the LV outflow tract with fluoroscopic guidance. After placement, TEE showed the Impella to be in good position across the AV (midesophageal aortic long-axis, transgastric long-axis views), with the inlet zone in the LV, and the outlet area in the ascending aorta (Figs. 1 and 2). LV inflow through the mitral valve (MV) was adequate and there was no mitral regurgitation noted after device placement (midesophageal 4-chamber view, midesophageal aortic long-axis views). Color flow images of the AV showed no significant insufficiency (midesophageal aortic long-axis view [Video 2, see Supplemental Digital Content 2, http://links.lww.com/AA/A331], deep transgastric view). No other changes were noted, and after reexamination of the device position, the Impella was secured to the leg. The patient was hemodynamically supported by both the TandemHeart and Impella for 7 days until systemic end-organ function recovered. The patient then received a biventricular assist device. He received a heart transplant several months later and was discharged home. Written consent to report the case was obtained from the patient described in this Echo Rounds.

The effect of the arterial catheter insertion technique on the success of radial artery cannulation: A prospective and randomized study☆

PURPOSE The main objective of the current investigation was to compare a single wall puncture to vessel transfixing on the success of radial artery cannulation by resident physicians. MATERIAL AND METHODS The study was a prospective and randomized investigation. Twelve anesthesiology residents performed radial arterial insertions in 126 patients using both the single wall and vessel transfixing technique in random order. The primary outcome was successful cannulation of the radial artery in 4 or less attempts. Other data collected included the total number of attempts and total time to catheter cannulation. RESULTS Successful radial artery cannulation was achieved in 88% and 86% of patients using the transfixing technique and single wall group, respectively (difference 2%; 95% CI, 14-9, P=0.8, Fisher exact test). Cannulation was successfully on the first attempt in 38% of the transfixing compared to 54% using the single wall technique (difference--16%; 95% CI, 32-2, P=0.1, Fisher Exact test). The median (interquartile range) time to successful cannulation was longer in the transfixing group, 105 (69-176) seconds compared to 65 (25-114) seconds in the single puncture group (P=.009, log-rank test). CONCLUSIONS Our findings suggest that there does not appear to be an advantage of the transfixing technique over the single wall puncture method for cannulating the radial artery by resident physicians. Cannulation was achieved in shorter time using the single wall puncture technique even after accounting for differences between residents and prior levels of experience.

Cerebral Neuromonitoring During Cardiac Surgery: A Critical Appraisal With an Emphasis on Near-Infrared Spectroscopy

Neurological complications of cardiac surgery have a large effect on patient outcomes. In this review, the value of several modes of central nervous system monitoring for improving perioperative care is critiqued. The electroencephalogram (EEG) has been used as a means for detecting brain ischemia. Even though EEG changes are specific for ischemia, the reliability is tempered by many confounding factors. The effectiveness of the processed EEG for ensuring amnesia during surgery is controversial, but it may have value for optimizing anesthetic dose and thus reducing the risk for delirium. Transcranial Doppler may be beneficial in confirming flow to both cerebral hemispheres during antegrade cerebral perfusion such as during aortic arch surgery and in detecting cerebral emboli. Transcranial Doppler can be used for monitoring cerebral autoregulation, allowing for individualization of blood pressure targets during surgery. Measures of adequacy of cerebral oxygen balance include jugular bulb venous oxygen saturation and near-infrared spectroscopy monitoring. Both monitors have limitations that reduce the sensitivity for detecting brain ischemia. Because near-infrared spectroscopy-measured regional cerebral oxygen saturation does not distinguish arterial from venous blood, these measurements reflect the adequacy of oxygen delivery versus demand. Over short periods, filtered regional cerebral oxygen saturation data may provide a clinically feasible method of monitoring cerebral autoregulation that overcomes many limitations of transcranial Doppler. Ongoing studies have demonstrated that the latter methodology for determining perioperative blood pressure targets has large potential for reducing organ injury from cardiac surgery.

The risk of cesarean delivery with neuraxial analgesia given early versus late in labor

The recommendation that epidural anesthesia be delayed in nulliparous women until there is 4-5 cm of cervical dilatation rests on an increased risk of cesarean delivery at less than 4.0 cm. It is not clear whether this isa result of the analgesia or other factors. The authors postulated that neuraxial analgesia administered early in labor using intrathecal opioid, as part of a low-dose local anesthetic technique, would not increase the risk of operative delivery. A randomized trial enrolled 728 nulliparous women at term who either were in spontaneous labor or had spontaneous rupture of membranes and whose cervical dilatation was less than 4.0 cm. The participants received either intrathecal fentanyl, with bupivacaine added as needed, or systemic (intravenous and intramuscular) hydromorphone when they first asked for analgesia. Epidural analgesia was started at the second request for analgesia in the intrathecal group, and at cervical dilatation of 4.0 or more, or at the third request for pain relief in the systemic group. Rates of cesarean delivery did not differ significantly between the 2 groups, and there also were no significant differences in the rate of instrumental vaginal delivery or indications for operative delivery. The maximum rate of oxytocin infusion was, however, higher in women given systemic analgesia. Neither type of insurance (private or public) nor different obstetric providers made a difference. Times from initial analgesia to complete dilatation and vaginal delivery were significantly shorter when intrathecal analgesia was used. The intrathecal group had less nausea and vomiting, and neuraxial analgesia lasted longer in this group than in women given systemic analgesia. There was no significant group difference in worrisome fetal heart rate tracings. The findings in this randomized trial indicate that nulliparous women in spontaneous labor, or having spontaneous membrane rupture, may receive neuraxial analgesia early in the course of labor without adverse effects. Early neuraxial analgesia does not appear to increase the number of cesarean deliveries compared with systemic opioid analgesia, and it may shorten labor.