Left Lateral Tilt Research Articles

앙와위와 좌측 기울린위치에서의 좌심실의 공간적 관계 변화. 임신부 심폐소생술 측면에서

Application of the left lateral tilt position has been recommended during cardiopulmonary resuscitation (CPR) of pregnant patients. However, the left lateral tilt could displace the left ventricle (LV) besides the gravid uterus and may compromise the cardiac pump mechanism of CPR. Thus, we investigated the effect of left lateral tilt on the spatial relationship between the anterior-posterior axis (AP axis), which represents the direction of sternal displacement during CPR, and the LV. We retrospectively reviewed the medical records and multidetector computed tomography (MDCT) scans of 90 patients who underwent virtual gastroscopy using MDCT. Virtual gastroscopy was performed with the patient both in the left lateral tilt position and in the supine position. On an axial image showing the maximal area of the LV, the angle between the AP axis and the LV axis (), the shortest distance between the AP axis and the mid-point of LV cavity () and the shortest distance between the AP axis and the LV apex () were measured. In the supine scans, the LV was situated on the left side of the AP axis in 87 patients (96.7%). On the left lateral tilt scans, the mean tilt angle was . and were significantly longer in the left lateral tilt position (p was comparable between the positions. This study indicates that the left lateral tilt position may compromise the cardiac pump mechanism of chest compression in pregnant cardiac arrest patients.

CONGENITAL MUSCULAR TORTICOLLIS AND CERVICAL DYSTONIA

Congenital muscular torticollis persisting to adult life is rare.1 Patients have a head tilt and a cord like sternocleidomastoid. It must be distinguished from adult onset cervical dystonia. Botulinum toxin...

Cardiopulmonary resuscitation in the pregnant patient: a manikin‐based evaluation of methods for producing lateral tilt

The importance of minimising aortocaval compression during cardiopulmonary resuscitation in late pregnancy is widely accepted. Current European guidelines suggest employing manual displacement of the uterus with left lateral tilt to achieve this. Several methods for producing lateral tilt have been described; however, the optimum method is unknown. By performing simulated cardiopulmonary resuscitation on a manikin, we compared four of these methods: a folded labour ward pillow; a pre-formed foam wedge; a custom-made hard wooden wedge; and the 'human wedge'. Primary outcome measures were maintenance of adequate tilt, stability and effectiveness of chest compressions (rate, depth and adequate release). Overall, the foam and wooden wedges were significantly more stable and reliable at maintaining tilt than the pillow (p<0.0001); the wooden wedge was more stable and effective than the foam wedge (p<0.0001). Chest compressions were least effective with the human wedge (p=0.02). Effectiveness of chest compressions with lateral tilt was comparable to that reported previously in supine manikin studies. We recommend the use of dedicated foam or hard wedges rather than pillows or the human wedge for producing lateral tilt during cardiopulmonary resuscitation.

Utility of the Pentax-AWS Airwayscope and Macintosh laryngoscope for airway management during chest compressions in 27° left-lateral tilt: a manikin simulation study of maternal cardiopulmonary resuscitation

American Heart Association (AHA) 2010 cardiopulmonary resuscitation guidelines recommend high-quality chest compressions (minimum interruption, a pace >100 compressions/min, and a depth more than 5 cm). They propose minor changes for pregnant women: manual left deviation of the uterus or a left-lateral incline of 27°-30° to alleviate pressure on the inferior vena cava. We examined the performance of the Pentax-AWS Airwayscope (AWS) and Macintosh laryngoscope (McL) for airway management during chest compressions on a 27° left-lateral tilt (27 LLT) operating table. The study included 18 novice doctors in our anesthesia department. They performed tracheal intubation on a manikin positioned on a 27 LLT operating table using the AWS or McL with or without chest compressions. We measured the intubation time and success rate for tracheal intubation. Intubation success rate with the McL decreased with chest compressions compared to without chest compressions (12/18 vs. 18/18, P < 0.05). Intubation time with the McL was lengthened with chest compressions compared to without chest compressions (18.9 ± 4.0 s vs. 11.1 ± 1.0 s, P < 0.05). Intubation success rate was the same for the AWS with and without chest compressions (18/18 in both cases), and intubation time did not increase significantly without compressions compared to with compressions (11.6 ± 1.4 s vs. 12.6 ± 1.2 s, NS). The AWS is an effective tool for airway management during chest compressions in 27 LLT in a manikin, suggesting that the AWS may be a useful device for airway management during maternal resuscitation.

Maternal position during caesarean section for preventing maternal and neonatal complications

During caesarean section mothers can be in different positions. Theatre tables could be tilted laterally, upwards, downwards or flexed and wedges or cushions could be used. There is no consensus on the best positioning at present. We assessed all available data on positioning of the mother to determine if there is an ideal position during caesarean section that would improve outcomes. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (20 August 2012), PubMed (1966 to 20 August 2012) and manually searched the references of retrieved articles. Randomised trials of woman undergoing caesarean section comparing different positions. Two review authors assessed eligibility, trial quality and extracted data. We identified 22 studies with a total of 857 women included. We included 11 studies and excluded 11. Included trials were of variably quality with small sample sizes. Most comparisons had data from single trials. This is a shortcoming and applicability of results is limited.The incidence of air embolism was not affected by head up versus horizontal position (average risk ratio (RR) 0.85; 95% confidence interval (CI) 0.28 to 2.57; Tau² = 0.50; I² = 74%).We found no change in hypotensive episodes when comparing left lateral tilt (RR 0.11; 95% CI 0.01 to 1.94), right lateral tilt (RR 1.25; 95% CI 0.39 to 3.99), a right lumbar pelvic wedge (RR 0.85; CI 0.53 to1.37) and head down tilt (RR 1.07; 95% CI 0.81 to 1.42) with horizontal positions. We found no change in hypotensive episodes when comparing full lateral tilt with 15-degree tilt (RR 1.20; 95% CI 0.80 to 1.79). Hypotensive episodes were decreased with manual displacers (RR 0.11; 95% CI 0.03 to 0.45), and increased with a right lumbar wedge compared with a right pelvic wedge (RR 1.64; 95% CI 1.07 to 2.53) and increased with a right lateral tilt compared with a left lateral tilt (RR 3.30; 95% CI 1.20 to 9.08).Position did not affect systolic blood pressure when comparing left lateral tilt (MD 2.70; 95% CI -1.47 to 6.87) or head down tilt (MD -3.00; 95% CI -8.38 to 2.38) with horizontal positions, or full lateral tilt with 15-degree tilt (MD -5.00; 95% CI -11.45 to 1.45). Manual displacers showed decreased fall in mean systolic blood pressure compared with left lateral tilt (MD -8.80; 95% CI -13.08 to -4.52).Position did not affect diastolic blood pressures when comparing left lateral tilt versus horizontal positions (MD-1.90; 95% CI -5.28 to 1.48). The mean diastolic pressure was lower in head down tilt (MD -7.00; 95% CI -12.05 to -1.95) when compared with horizontal positions.There were no statistically significant changes in maternal pulse rate, five-minute Apgars, maternal blood pH or cord blood pH when comparing different positions. There is limited evidence to support or clearly disprove the value of the use of tilting or flexing the table, the use of wedges and cushions or the use of mechanical displacers. A left lateral tilt may be better than a right lateral tilt and manual displacers may be better than a left lateral tilt but larger studies with more robust data are needed to confirm these findings.

Intra- and Interday Reliability of Spine Rasterstereography

To determine intra- and interday reliability of spine rasterstereographic system Formetric 4D with and without reflective markers. Twenty-six healthy volunteers (M group) had two markers placed in correspondence of vertebra prominens and intergluteal cleft, and 24 volunteers (NM group) were assessed without markers. All participants were analyzed two times in the same day and one time on a separate day. Trunk length, kyphotic angle, lordotic angle, pelvic inclination, kyphotic and lordotic apex, right and left lateral deviation, flèche cervicale and lombaire, trunk imbalance, pelvic tilt, inflection point, rotation correction, right and left surface rotation, pelvic torsion, and trunk torsion were measured. Intraclass correlation coefficient (ICC) and Cronbach Alpha (Cα) were calculated. In M group, for intra-, interday, and overall evaluations, the higher reliability coefficients were 0.971, 0.963, and 0.958 (ICC) and 0.987, 0.983, and 0.985 (Cα) for trunk length, kyphotic angle, and lordotic apex, respectively; while in NM group, they were 0.978, 0.982, and 0.972 and 0.989, 0.991, and 0.991 for trunk length. In M group, the lower values were 0.598, 0.515, and 0.534 (ICC) and 0.742, 0.682, and 0.784 (Cα) for trunk and pelvic torsion and in NM group 0.561, 0.537, and 0.461 and 0.731, 0.695, and 0.729 for left lateral deviation. The reliability of most parameters was excellent.

Haemodynamic effects from aortocaval compression at different angles of lateral tilt in non-labouring term pregnant women

Aortocaval compression (ACC) can result in haemodynamic disturbances and uteroplacental hypoperfusion in parturients. Its detection is difficult because in most patients, sympathetic compensation results in no signs or symptoms. However, profound hypotension may develop after sympathectomy during regional anaesthesia. In this prospective observational study, we aimed to detect ACC by analysing haemodynamic changes in term parturients who were positioned sequentially at different angles of lateral tilt. We studied haemodynamic changes in 157 non-labouring term parturients who were positioned in random order at 0°, 7.5°, 15°, and full left lateral tilt. Cardiac output (CO), stroke volume, and systemic vascular resistance were derived using suprasternal Doppler. Non-invasive arterial pressure (AP) measured in the upper and lower limbs was analysed to detect aortic compression. CO was on average 5% higher when patients were tilted at ≥15° compared with <15°. In a subgroup of patients (n=11), CO decreased by more than 20%, without changes in systolic AP, when they were tilted to <15° which was considered attributable to severe inferior vena caval compression. Only one patient in the supine position had aortic compression with the systolic AP in the upper limb 25 mm Hg higher than the lower limb. Patients with ACC can be identified by the CO changes from serial measurements between supine, 15°, or full lateral tilt. Our findings suggest that in non-labouring parturients, ACC is asymptomatic and can be effectively minimized by the use of a left lateral tilt of 15° or greater.

Resuscitation of the pregnant patient: What is the effect of patient positioning on inferior vena cava diameter?

Study objectivePatients in the third trimester of pregnancy presenting to the emergency department (ED) with hypotension are routinely placed in the left lateral tilt (LLT) position to relieve inferior vena cava (IVC) compression from the gravid uterus thereby increasing venous return. However, the relationship between patient position and proximal intrahepatic IVC filling has never assessed directly. This study set out to determine the effect of LLT position on intrahepatic IVC diameter in third trimester patients under real-time visualization with ultrasound. MethodsThis prospective observational study on the labor and delivery floor of a large urban academic teaching hospital enrolled patients between 30 and 42 weeks estimated gestational age from August 2011 to March 2012. Patients were placed in three different positions: supine, LLT, and right lateral tilt (RLT). After the patient was in each position for at least 3min, IVC ultrasound using the intercostal window was performed by one of three study sonologists. Maternal and fetal hemodynamics were also monitored and recorded in each position. ResultsA total of 26 patients were enrolled with one excluded from data analysis due to inability to obtain IVC measurements. The median IVC maximum diameter was 1.26cm (95% confidence interval [CI] 1.13–1.55) in LLT compared to 1.13cm (95% CI 0.89–1.41) in supine, p=0.01. When comparing each individual patient's LLT to supine measurement, LLT lead to an increase in maximum IVC diameter in 76% (19/25) of patients with the average LLT measurement 29% (95% confidence interval 10–48%) larger. Six patients had the largest maximum IVC measurement in the supine position. No patients experienced any hemodynamic instability or distress during the study. ConclusionIVC ultrasound is feasible in late pregnancy and demonstrates an increase in diameter with LLT positioning. However, a quarter of patients had a decrease in IVC diameter with tilting and, instead, had the largest IVC diameter in the supine position suggesting that uterine compression of the IVC may not occur universally. IVC assessment at the bedside may be a useful adjunct in determining optimal positioning for resuscitation of third trimester patients.

EComment. Left tilt position for cardiopulmonary bypass in parturient patients

We read with great interest the paper by Ngatchou et al [1]. The 28-year old pregnant woman underwent a successful implantation of a veno-venous extracorporeal membrane oxygenation for acute respiratory distress syndrome of unknown origin. The insertion of the right and the left venous femoral cannula was facilitated by placing a wedge-shaped cushion under the right hip. The authors stated that the left tilt position used in this case report is recommended for pregnant women in two situations: in a caesarean section and in cardiopulmonary resuscitation. However, the left lateral tilt position is also recommended in parturients undergoing cardiopulmonary bypass (CPB) for cardiac surgery. Reducing the compression of the inferior vena cava by the foetus is mandatory to allow for better venous return during CBP. This will prevent hypotension that occurs in case of poor venous return when the circulation goes from corporeal to extracorporeal. The collapse of peripheral resistance can bring about a brisk decrease of the mean arterial pressure and a secondary reduction of placental perfusion. In the current era, CPB during pregnancy can be performed with relative safety when performed at tertiary centers with the expertise [2]; however it is still associated with substantial morbidity and mortality [3]. We would like to share our experience relating to two parturients operated on an emergent basis with the use of CPB during the last three years at our institution and to highlight the important role of the left lateral tilt position during CPB. A 30-year-old woman at 26 weeks of gestation was admitted because of the acute onset of severe chest pain. Echocardiography revealed a tricuspid aortic valve with mild aortic regurgitation, and an acute aortic dissection involving the ascending aorta, which was also verified by a computed tomography scan. CPB was instituted between the right atrium and the right axillary artery. Hypothermia was avoided and the operation consisted of replacing the supracoronary ascending aorta. A 39-year-old woman underwent a successful pulmonary embolectomy at the 27th week of pregnancy. We performed surgical pulmonary embolectomy under CPB to restore adequate hemodynamic stability and to relieve strain on the right ventricle [4]. In both cases, the left lateral tilt position was applied and the venous return was very satisfactory. The pregnancies were carried to term and healthy newborns at 36 and 38 weeks of gestation were delivered, respectively. Conflict of Interest: None declared.

Effect of positioning from supine and left lateral positions to left lateral tilt on maternal blood flow velocities and waveforms in full‐term parturients

Effect of positioning from supine and left lateral positions to left lateral tilt on maternal blood flow velocities and waveforms in full‐term parturients

Effect of positioning from supine and left lateral positions to left lateral tilt on maternal blood flow velocities and waveforms in full‐term parturients

Positioning the parturient from supine to the left lateral tilt position (supine-to-tilt) may not effectively displace the gravid uterus, but turning from the left lateral position to the left lateral tilt position (left lateral-to-tilt) may keep the gravid uterus displaced and prevent aortocaval compression. Fifty-one full-term parturients were randomly placed in the left lateral position, supine-to-tilt and left lateral-to-tilt positions using a Crawford wedge. Femoral vein area, femoral vein velocity, femoral artery area, pulsatility index, resistance index and right arm mean arterial blood pressure and heart rate were recorded. Our results showed a lower mean (SD) femoral vein area (82.2 (14.9) vs 96.2 (16.4) mm(2)), a lower pulsatility index (3.83 (1.3) vs 5.8 (2.2)), a lower resistance index (0.93 (0.06) vs 0.98 (0.57)), a higher femoral artery area (33.3 (3.8) vs 30.9 (4.4) mm(2)) and a higher femoral vein velocity (7.9 (1.2) vs 6.1 (1.6) cm.s(-1)) with left lateral-to-tilt when compared with supine-to-tilt (all p < 0.001). Our results suggest that moving a full-term parturient from the full left lateral to the lateral tilt position may prevent aortocaval compression in full-term parturients more efficiently than when positioning the parturient from a supine to left lateral tilt position.

Left tilt position for easy extracorporeal membrane oxygenation cannula insertion in late pregnancy patients

The aim was to describe how to avoid technical difficulties during venous femoral cannula insertion for extracorporeal membrane oxygenation (ECMO) in a woman in late pregnancy. A 28-year old pregnant woman presented at 32 weeks of gestation after developing an acute respiratory distress syndrome (ARDS) of an unknown origin that required venovenous ECMO insertion via the femoral vein. A cannula insertion by the Seldinger visual control technique was impossible in the supine position. A left lateral tilt between 15° and 30° was performed by placing a wedge-shaped cushion under the right hip permitting the cannula insertion. We proposed a systematic 15°-30° left lateral tilt position during the ECMO femoral cannula insertion in late pregnancy cases needing ECMO. This precaution should avoid an injury to the vessels due to multiple insertion attempts.

Cardiac arrest in pregnancy: lessons to be learned!

Dear Editor, Cardiac arrest in pregnancy is a rare event with an incidence of 1 per 30,000 pregnancies in western countries. However, it is important for emergency physicians to be familiar with the indications for performing a perimortem caesarean section (PMCS). We report two cases of PMCS performed during cardiopulmonary resuscitation (CPR). The first case, a 37-year-old female, G1P0, had a medical history of epilepsy. Her pregnancy was complicated at 30 weeks gestation by a single uncomplicated grand mal seizure as a result of low valproate level. She was admitted, at 35 weeks gestation, for pregnancy-induced hypertension. Laboratory results were normal. Two days after admission she was found unresponsive. She had pulseless electrical activity (PEA) and hypoxia due to an epileptic insult was considered the diagnosis. She was treated according to the advanced cardiac life support protocol. Fifteen min after the start of CPR a PMCS was performed. There was an immediate return of spontaneous circulation (ROSC). Unfortunately 2 days later her treatment had to be withdrawn, because of poor neurological prognosis. The male infant (2,300 g; Apgar score 0/6/7) had seizures and was resuscitated. The baby survived, and follow-up 12 months after delivery showed normal growth and slight neurologic development impairment. The second case, a 35-year-old female, G3P1, had an uneventful medical history and was admitted for induction of labour at 41 weeks and 3 days gestation. After spontaneous rupture of membranes the patient suffered from dyspnoea, hypotension, bradycardia, and cyanosis. Supplemental oxygen and left lateral tilt position did not alleviate the symptoms. Upon arrival of the resuscitation team the patient had PEA. Amniotic fluid embolism was considered the diagnosis. Perimortem caesarean section was performed in the delivery room after 4 min, resulting in the immediate ROSC and the birth of a girl (3,450 g; Apgar score 2/6/7). Both were discharged without abnormalities. During CPR in late pregnancy the patient should be positioned in left lateral tilt to alleviate aortocaval compression [1]. If sufficient cardiac output is not achieved within 4 min after cardiac arrest, in a pregnancy of more than 20 weeks gestation, PMCS must be considered [1]. In our cases an important observation was made that immediately after delivery of the infant there was a ROSC, indicating that indeed pooling of blood in the uterus and placenta as well as aortocaval compression played a pivotal role in the prior unsuccessful resuscitation. We performed two PMCS in our hospital. The first PMCS was before the courses based on the Managing Obstetric Emergencies and Trauma (MOET) principles were given at our institution [2, 3]. Important differences between the first and second case were the immediate awareness of the necessity to perform PMCS in the first 4 min after persistent cardiopulmonary arrest, the availability of an emergency PMCS box [4] in the delivery room and the notion to perform the PMCS on the spot. This all resulted in a much faster delivery of the baby and more importantly much faster return of the maternal circulation, resulting in favourable clinical outcome for both mother and child.

Measurement of intra-abdominal pressure in term pregnancy: a pilot study

BackgroundThis study was conducted to assess the feasibility of measuring intra-abdominal pressure in term parturients under spinal anesthesia. MethodsIntra-abdominal pressure was measured in 20 term parturients after spinal anesthesia for elective caesarean section. Pressure was measured in the supine and 10° left lateral tilt positions with a constant reference point throughout. ResultsIntra-abdominal pressure measurement was feasible and safe to perform. Pressure was significantly lower in the left lateral tilt position than supine (10.9mmHg±4.67 vs. 8.9mmHg±4.87, P=0.0004). The range of intra-abdominal pressure in pregnancy was wide, from 2 to 20mmHg, with >25% of patients resting with pressures above 12mmHg in both positions. ConclusionsUnder spinal anesthesia, intra-abdominal pressure in >25% of healthy term parturients was > 12mmHg, which has conventionally been defined as intra-abdominal hypertension. The intra-abdominal pressure in term pregnancy should be performed in the left lateral tilt position to avoid falsely elevated pressure measurements.

Theoretical Analysis of the Effect of Positioning on Hemodynamic Stability During Pregnancy

A left lateral tilt of 15° has been advocated during trauma resuscitation of near-term pregnant patients to avoid the potential for hemodynamic compromise caused by aortocaval compression in the supine position. This recommendation is supported by limited objective evidence, and an experimental determination of the optimal tilt required would be very difficult to accomplish logistically. A derivation of the Guyton/Coleman/Summers computer model of cardiovascular physiology was used to analyze the theoretically expected hemodynamic responses to varying degrees of lateral tilt for a normal pregnancy and during a simulated hemorrhagic shock. Computer simulation studies were used to predict the degree of left lateral tilt required to restore hemodynamic normalcy during the final 20 weeks of gestation. The analytic procedure involved recreating the clinical conditions for a virtual subject through a simulated reenactment of the clinical transfer of a pregnant patient from a lateral to a supine positioning. An analysis of model validity in the context of this particular clinical condition found the model predictions to be within 5% to 12% of experimental results. During the simulated lateral to supine position transfer, the virtual patient with Class I hemorrhage had a 7% greater fall in cardiac output and a 17% greater fall in mean arterial pressure (MAP) than the corresponding nonhemorrhagic patient. The model suggests that 15° of tilt will result in hemodynamic normalization only up to 26 weeks of gestation. In addition, 13% greater tilt is required to achieve hemodynamic normalcy in the hemorrhaged term pregnant patient. Current trauma guidelines suggest that the pregnant trauma patient be placed in a 15° left lateral tilt position to prevent aortocaval compression. A computer simulation study suggests that this tilt may be inadequate to offload the vena cava and normalize the circulation.

Maternal Cardiac Output Changes After Crystalloid or Colloid Coload Following Spinal Anesthesia for Elective Cesarean Delivery

Minimizing hypotension associated with spinal anesthesia for cesarean delivery by administration of IV fluids and vasopressors reduces fetal and maternal morbidity. Most studies have concentrated on noninvasive systolic blood pressure (SBP) measurements to evaluate the effect of such regimens. We used a suprasternal Doppler flow technique to measure maternal cardiac output (CO) variables in parturients receiving a phenylephrine infusion combined with the rapid administration of crystalloid or colloid solution at the time of initiation of anesthesia (coload). We hypothesized that a colloid coload compared with a crystalloid coload would produce a larger sustained increase in CO and therefore reduce vasopressor requirements. We recruited 60 healthy term women scheduled for elective cesarean delivery under spinal anesthesia for this randomized double-blind study. Baseline heart rate, baseline SBP, and CO variables including stroke volume, corrected flow time, and contractility were recorded in the left lateral tilt position. At the time of spinal injection, subjects were allocated to receive a rapid 1-L coload of either 6% w/v hydroxyethyl starch solution (HES) or Hartmann (crystalloid) solution (HS). A phenylephrine infusion was titrated to maintain maternal baseline SBP. CO was measured at 5-minute intervals for 20 minutes after initiation of spinal anesthesia. The primary outcome, CO, was compared between groups, as were secondary outcomes: phenylephrine dose and maternal hemodynamic and fetal outcome data. Maternal demographics, surgical times, and fetal outcome data were similar between groups. There were no significant differences between groups in any measured CO variable at any time point. CO was transiently higher than baseline at 5 minutes in the HS group and at 5 and 10 minutes in the HES group (range, 0.13-1.74 L/min); the overall mean difference in CO between crystalloid and colloid over the study period was 0.06 L/min (95% confidence interval: -0.46 to 0.58). Stroke volume was higher than baseline in both groups throughout; peak velocity was consistently higher than baseline only in the HES group; and corrected flow time increased in both groups; the effect was transient in the HS but sustained in the HES group. Heart rate was not different at any time point within or between groups but did decrease over time. The total phenylephrine dose from time of spinal anesthesia to delivery was similar between groups. We found no difference in CO in women randomized to colloid or crystalloid coload. In addition, there were no differences in vasopressor requirements or hemodynamic stability. We conclude that there is no advantage in using colloid over crystalloid when used in combination with a phenylephrine infusion during spinal anesthesia for elective cesarean delivery.

False-Positive Pericardial Effusion Due to Breast Attenuation on Equilibrium Radionuclide Angiocardiography

Equilibrium radionuclide angiocardiography (ERNA) scans are used to evaluate left ventricular function and pericardial anatomy. A photopenic "U-halo" around the cardiac blood pool in the left anterior oblique (LAO) view is commonly seen with pericardial effusion. We describe findings of false-positive pericardial effusion due to breast attenuation in cancer patients. Several cases that demonstrated the photopenic U-halo in the LAO view did not have true pericardial effusion. The patients' breast size and how far the breast sagged in reference to the heart silhouette were visually observed in topograms. The oblique tilt position was evaluated to determine the effect it may have in creating the photopenic U-halo. A unique ERNA case demonstrating collateral vessels bilaterally in the breasts was used as a reference marker image to determine the effect of a slightly more anterior versus left lateral oblique tilt in the LAO view. Large breasts can overlie the heart in the LAO projection. The overlying breast can cause the appearance of pericardial effusion in the resulting image by attenuating tissues surrounding the heart. The positioning of the breast also affected the appearance of the photopenic halo. A patient with breast implants who had more upright breasts demonstrated a photopenic area anterior to the left ventricle, whereas a large breast that sagged more laterally demonstrated no photopenic area. Patients with large breasts may show a photopenic U-halo in the LAO view dependent on how far the breast sags in reference to the heart silhouette and on the positioning of the oblique tilt. The anterior image should be used to distinguish breast attenuation from a photopenic area surrounding the heart. If both the anterior view and the LAO view demonstrate the U-halo, acquiring another view with a slightly more anterior or lateral oblique position will demonstrate any inconsistency in the photopenic area, thereby excluding a diagnosis of pericardial effusion.

The Effects of Crystalloid and Colloid Preload on Cardiac Output in the Parturient Undergoing Planned Cesarean Delivery Under Spinal Anesthesia

Obstetric Anesthesia Digest: March 2011 - Volume 31 - Issue 1 - p 54-56 doi: 10.1097/01.aoa.0000393191.66961.a6

Table tilt versus pelvic tilt position for intrauterine resuscitation during spinal anaesthesia for caesarian section

This study was undertaken to compare the effects on intrauterine resuscitation by table tilt versus pelvic tilt position after spinal anaesthesia for Caesarian Section. PATIENTS #ENTITYSTARTX00026; FIFTY ASA I AND II PATIENTS WHO FULFILLED THE ELIGIBILITY CRITERIA WERE ENROLLED IN THE STUDY AND WERE DIVIDED INTO TWO GROUPS: group W (Pelvic tilt with wedge under right hip and group L- (15(0)left lateral table tilt) and received spinal anaesthesia. The following parameters were recorded. Heart rate (HR), mean arterial pressure (MAP) at baseline, 2mins, 5 min and then 5 min thereafter. Mean height of block, Total no. of segments blocked, Onset Time of sensory block (in Minutes), ephedrine doses, incidence of hypotension & bradycardia, APGAR score at 1& 5 Minutes. The decrease in MAP was much more in wedged position as compared to table tilt position also the incidence of hypotension was 40% in wedged position as compared to 12% in table tilt position. Mean height of block, Total no. of segments blocked, and boluses of inj. ephedrine used were more in the wedged position than in table tilt position. Wedge placement caused increased incidence of hypotension and higher blockade after spinal anaesthesia as compared to left lateral table tilt position, there was no adverse effects on foetus and patients tolerated wedge better than left lateral table tilt position. Also surgery was easier to perform after wedge placement.

Part 12: Cardiac Arrest in Special Situations

This section of the 2010 AHA Guidelines for CPR and ECC addresses cardiac arrest in situations that require special treatments or procedures beyond those provided during basic life support (BLS) and advanced cardiovascular life support (ACLS). We have included 15 specific cardiac arrest situations. The first several sections discuss cardiac arrest associated with internal physiological or metabolic conditions, such as asthma (12.1), anaphylaxis (12.2), pregnancy (12.3), morbid obesity (12.4), pulmonary embolism (PE) (12.5), and electrolyte imbalance (12.6). The next several sections relate to resuscitation and treatment of cardiac arrest associated with external or environmentally related circumstances, such as ingestion of toxic substances (12.7), trauma (12.8), accidental hypothermia (12.9), avalanche (12.10), drowning (12.11), and electric shock/lightning strikes (12.12). The last 3 sections review management of cardiac arrest that may occur during special situations affecting the heart, including percutaneous coronary intervention (PCI) (12.13), cardiac tamponade (12.14), and cardiac surgery (12.15). Asthma is responsible for more than 2 million visits to the emergency department (ED) in the United States each year, with 1 in 4 patients requiring admission to a hospital.1 Annually there are 5,000 to 6,000 asthma-related deaths in the United States, many occurring in the prehospital setting.2 Severe asthma accounts for approximately 2% to 20% of admissions to intensive care units, with up to one third of these patients requiring intubation and mechanical ventilation.3 This section focuses on the evaluation and treatment of patients with near-fatal asthma. Several consensus groups have developed excellent guidelines for the management of asthma that are available on the World Wide Web: ### Pathophysiology The pathophysiology of asthma consists of 3 key abnormalities: Complications of severe asthma, such as tension pneumothorax, lobar atelectasis, pneumonia, and pulmonary edema, can contribute to fatalities. Severe asthma exacerbations are commonly associated with …