Efficacy of surface landmark palpation for identification of the cricoid cartilage in obstetric patients: A prospective observational study.

BACKGROUND AND AIMS: Rapid sequence induction, with the application of cricoid pressure is an accepted practice during induction of general anesthesia in pregnant patients to prevent pulmonary apiration. We found no prior studies assessing the accuracy of locating the cricoid cartilage by professional caregivers, and therefore conducted an observational study to assess the ability of different caregivers - anesthesia consultants, anesthesia residents, respiratory therapists (RTs), and nurses, in the obstetric care unit, to correctly identify the cricoid cartilage of parturients. We hypothesized that anesthesia consultants would be most accurate. MATERIAL AND METHODS: Institutional REB approval was obtained, as was written informed consent from all participants in the study. The subjects were made up of thirty healthy obstetric patients scheduled for elective cesarean delivery. Their cricoid cartilages were assessed by 53 caregivers (assessors). Localization of the cricoid cartilage by assessors was considered accurate if it was within 5 mm of the sonographically identified mark. The difficulty in localization was reported on a VAS scale and the time taken for localization was recorded. RESULTS: Data from 30 subjects and 53 assessors (13 anesthesia consultants, 12 residents, 13 RTs, and 15 nurses) performing a total of 60 evaluations (some assessors evaluated 2 subjects) were analyzed. About 60% of RTs, 53% of anesthesia residents, 40% of anesthesia consultants, and 13% of nurses correctly identified the cricoid cartilage. No differences in caregivers'perception of difficulty were found, but RTs were the quickest at identification (P < 0.001 vs anesthesia consultants; P = 0.002 vs residents; P = 0.071 vs nurses). CONCLUSION: RTs were the most successful and accurate in identifying the cricoid cartilage of parturients among the different groups of professional caregivers.

Effect of table tilt and spine flexion-rotation on the acoustic window of the lumbar spine in pregnant women / Efeito da inclinação da mesa e flexão da coluna sobre a janela acústica da coluna lombar em mulheres grávidas

Abstract Study objective: The purpose of this study was to assess whether application of dorsal table tilt and body rotation to a parturient seated for neuraxial anesthesia increased the size of the paramedian target area for neuraxial needle insertion. Setting: Labor and Delivery Room. Patients: Thirty term pregnant women, ASA I-II, scheduled for an elective C-section delivery. Interventions: Lumbar ultrasonography was performed in four seated positions: (F) lumbar flexion; (FR) as in position F with right shoulder rotation; (FT) as in position F with dorsal table-tilt; (FTR) as in position F with dorsal table-tilt combined with right shoulder rotation. Measurements: For each position, the size of the 'target area', defined as the visible length of the posterior longitudinal ligament was measured at the L3-L4 interspace. Main results: The mean posterior longitudinal ligament was 18.4 ± 4 mm in position F, 18.9 ± 5.5 mm in FR, 19 ± 5.3 mm in FT, and 18 ± 5.2 mm in FTR. Mean posterior longitudinal ligament length was not significantly different in the four positions. Conclusions: These data show that the positions studied did not increase the target area as defined by the length of the posterior longitudinal ligament for the purpose of neuraxial needle insertion in obstetric patients. The maneuvers studied will have limited use in improving spinal needle access in pregnant women.

Resumo Objetivo do estudo: O objetivo deste estudo foi avaliar se a inclinação lateral da mesa cirúrgica e a rotação do corpo de uma parturiente sentada para anestesia neuraxial aumentou o tamanho da área-alvo paramediana para a inserção da agulha neuraxial. Ambiente: Sala de parto. Pacientes: Trinta grávidas a termo, ASA I-II, agendadas para cesárea eletiva. Intervenções: Ultrassonografia lombar foi feita em quatro posições sentadas: (F) flexão lombar; (FR) como na posição F com rotação do ombro direito; (FT) como na posição F com inclinação lateral da mesa cirúrgica; (FTR) como na posição F com inclinação lateral da mesa cirúrgica combinada com a rotação do ombro direito. Mensurações: Para cada posição, o tamanho da "área-alvo", definido como o comprimento visível do ligamento longitudinal posterior, foi medido no interespaço de L3-L4. Principais resultados: As médias do ligamento longitudinal posterior foram: 18,4 ± 4 mm na posição F; 18,9 ± 5,5 mm na posição FR; 19 ± 5,3 mm na posição FT e 18 ± 5,2 mm na posição FTR. O comprimento médio do ligamento longitudinal posterior não foi significativamente diferente nas quatro posições. Conclusões: Esses dados mostram que as posições avaliadas não aumentaram a área-alvo, conforme definido pelo comprimento do ligamento longitudinal posterior com o objetivo de inserção da agulha neuraxial em pacientes obstétricas. As manobras avaliadas terão um uso limitado na melhoria do acesso à agulha espinhal em mulheres grávidas.

[Effect of table tilt and spine flexion-rotation on the acoustic window of the lumbar spine in pregnant women]. / Efeito da inclinação da mesa e flexão da coluna sobre a janela acústica da coluna lombar em mulheres grávidas.

STUDY OBJECTIVE: The purpose of this study was to assess whether application of dorsal table tilt and body rotation to a parturient seated for neuraxial anesthesia increased the size of the paramedian target area for neuraxial needle insertion. SETTING: Labor and Delivery Room. PATIENTS: Thirty term pregnant women, ASA I-II, scheduled for an elective C-section delivery. INTERVENTIONS: Lumbar ultrasonography was performed in four seated positions: (F) lumbar flexion; (FR) as in position F with right shoulder rotation; (FT) as in position F with dorsal table-tilt; (FTR) as in position F with dorsal table-tilt combined with right shoulder rotation. MEASUREMENTS: For each position, the size of the 'target area', defined as the visible length of the posterior longitudinal ligament was measured at the L3-L4 interspace. MAIN RESULTS: The mean posterior longitudinal ligament was 18.4±4mm in position F, 18.9±5.5mm in FR, 19±5.3mm in FT, and 18±5.2mm in FTR. Mean posterior longitudinal ligament length was not significantly different in the four positions. CONCLUSIONS: These data show that the positions studied did not increase the target area as defined by the length of the posterior longitudinal ligament for the purpose of neuraxial needle insertion in obstetric patients. The maneuvers studied will have limited use in improving spinal needle access in pregnant women.

Ultrasound guided quadratus lumborum block for analgesia after cesarean delivery: case series / Bloqueio do quadrado lombar guiado por ultrassom para analgesia pós cesariana: série de casos

Abstract Introduction: The majority of women having planned cesarean section receive spinal anesthesia for the procedure. Typically, spinal opioids are administered during the same time as a component of multimodal analgesia to provide pain relief in the 16-24 h period postoperatively. The quadratus lumborum block is a regional analgesic technique that blocks T5-L1 nerve branches and has an evolving role in postoperative analgesia for lower abdominal surgeries and may be a potential alternative to spinal opioids. If found effective, it will have the advantage of a reduction in opioid associated adverse effects while providing similar quality of analgesia. Methods: We performed bilateral quadratus lumborum block in 3 women who received a spinal anesthetic for a cesarean delivery and evaluated their post-operative opioid consumption and patient satisfaction. Results: In all 3 patients, there was no additional opioid consumption during the first 24 h after the block. Numeric Rating Scale (NRS) for pain was less than 6 for the first 24 h. Women were all very satisfied with the quality of pain relief. Discussion: Quadratus lumborum block may be a promising anesthetic adjuvant for post-cesarean analgesia. Further randomized controlled trials are needed to compare the efficacy of the quadratus lumborum block with intrathecal opioids.

Resumo Introdução: A maioria das mulheres agendadas para cesariana recebe anestesia raquidiana para o procedimento. Tipicamente, os opioides administrados por via espinhal (VE) são administrados ao mesmo tempo como um componente da analgesia multimodal para proporcionar alívio da dor no período pós-operatório de 16-24 horas. O bloqueio do quadrado lombar (QL) é uma técnica de analgesia regional que bloqueia os ramos nervosos T5- L1 e tem um papel crescente na analgesia pós-operatória de cirurgias abdominais inferiores, pode ser uma potencial opção para os opioides VE. Se for considerado eficaz, esse bloqueio terá a vantagem de uma redução nos efeitos adversos associados aos opioides e proporcionará qualidade semelhante de analgesia. Métodos: O bloqueio bilateral do quadrado lombar foi feito em três mulheres que receberam raquianestesia para parto cesário e o consumo de opioides no pós-operatório e a satisfação das pacientes foram avaliados. Resultados: Em todas as três pacientes, não houve consumo adicional de opioide durante as primeiras 24 horas após o bloqueio. A escala de avaliação numérica (EAN) para dor foi inferior a 6 durante as primeiras 24 horas. Todas as mulheres ficaram muito satisfeitas com a qualidade do alívio da dor. Discussão: O bloqueio do QL pode ser um adjuvante promissor para analgesia pós-cesariana. Estudos randomizados e controlados são necessários para comparar a eficácia do bloqueio do quadrado lombar com opioides administrados por via intratecal.

[Ultrasound guided quadratus lumborum block for analgesia after cesarean delivery: case series]. / Bloqueio do quadrado lombar guiado por ultrassom para analgesia pós cesariana: série de casos.

INTRODUCTION: The majority of women having planned cesarean section receive spinal anesthesia for the procedure. Typically, spinal opioids are administered during the same time as a component of multimodal analgesia to provide pain relief in the 16-24h period postoperatively. The quadratus lumborum block is a regional analgesic technique that blocks T5-L1 nerve branches and has an evolving role in postoperative analgesia for lower abdominal surgeries and may be a potential alternative to spinal opioids. If found effective, it will have the advantage of a reduction in opioid associated adverse effects while providing similar quality of analgesia. METHODS: We performed bilateral quadratus lumborum block in 3 women who received a spinal anesthetic for a cesarean delivery and evaluated their post-operative opioid consumption and patient satisfaction. RESULTS: In all 3 patients, there was no additional opioid consumption during the first 24h after the block. Numeric Rating Scale (NRS) for pain was less than 6 for the first 24h. Women were all very satisfied with the quality of pain relief. DISCUSSION: Quadratus lumborum block may be a promising anesthetic adjuvant for post-cesarean analgesia. Further randomized controlled trials are needed to compare the efficacy of the quadratus lumborum block with intrathecal opioids.

A Prospective Observational Comparison Between Arm and Wrist Blood Pressure During Scheduled Cesarean Delivery.

BACKGROUND: Shivering is common during cesarean delivery (CD) under neuraxial anesthesia and may disrupt the measurement of noninvasive blood pressure (BP). BP measured at the wrist may be less affected by shivering. There have been no studies comparing trends in BP measured on the upper arm and wrist. We hypothesized that wrist systolic blood pressure (sBP) would accurately trend with upper arm sBP measurements (agree within a limit of ±10%) in parturients undergoing elective CD under spinal anesthesia or combined spinal-epidural anesthesia. METHODS: After initiation of spinal anesthesia, BP measurements were obtained simultaneously from the upper arm and wrist on opposite arms. The interval between measurements was 1 to 2 minutes, and data were collected for 20 minutes or until delivery. The primary outcome was agreement in dynamic changes in sBP measurements between the upper arm and the wrist. Bland-Altman plots indicating the levels of agreement between the methods were drawn for baseline measurements, over multiple measurements, and over multiple measurements on percentage change from baseline. RESULTS: Forty-nine patients were recruited and completed the study. The wrist sBP tended to overestimate the upper sBP for both baseline data (sBP bias = 13.4 mm Hg; 95% confidence interval = +10.4 to +16.4 mm Hg) and data obtained over multiple measurements (sBP bias = 12.8 mm Hg; 95% confidence interval = +9.3 to +16.3 mm Hg). For change in sBP from baseline over multiple measurements, the mean difference between the wrist and the arm sBP was -0.2 percentage points (99% limits of agreement -25 to +25 percentage points). CONCLUSIONS: The wrist measurement overestimated the reading relative to the upper arm measurement for multiple measurements over time. However, when the time series for each subject was examined for percentage change from baseline, the 2 methods mirrored each other in most cases. Nevertheless, our hypothesis was rejected as the limits of agreement were higher than ±10%. This finding suggests that wrist BP may not be an accurate method of detecting hypotension or hypertension during spinal or combined spinal-epidural anesthesia for CD.

Frequency of intraoperative cardiac arrest and medium-term survival.

CONTEXT AND OBJECTIVE: Although advances in surgical and anesthetic techniques have reduced perioperative morbidity-mortality, the survival rate following cardiac arrest remains low. The aim of this study was to evaluate, over the course of one year, the prevalence of intraoperative cardiac arrest and the 30-day survival rate after this event in a tertiary teaching hospital. DESIGN AND SETTING: Prospective cohort study in a tertiary teaching hospital. METHODS: Following approval by the institutional ethics committee, anesthetic procedures and cases of intraoperative cardiac arrest between January and December 2007 were evaluated. Patients undergoing cardiac surgery were excluded. The data were gathered prospectively using the modified Utstein model, with evaluation of demographic data, pre-arrest conditions, intraoperative care, care during arrest and postoperative outcome up to the 30th day. The data were recorded by the attending anesthesiologist. RESULTS: During the study period, 40,379 anesthetic procedures were performed, and 52 cases of intraoperative cardiac arrest occurred (frequency of 13:10,000). Among these, 69% presented spontaneous return of circulation after the initial arrest, and only 25% survived for 30 days after the event. The following factors were associated with shorter survival: American Society of Anesthesiologists physical status IV and V, emergency surgery, hemorrhagic events, hypovolemia as the cause of arrest and use of atropine during resuscitation. CONCLUSIONS: Although the frequency of cardiac arrest in the surgical environment has declined and resources to attend to this exist, the survival rate is low. Factors associated with worst prognosis are more frequent in critical patients.

Outcomes of patients with trauma and intraoperative cardiac arrest.

BACKGROUND: Although the occurrence of intraoperative cardiac arrest is rare, it is a severe adverse event with a high mortality rate. Trauma patients have additional causes for intraoperative arrest, and we hypothesised that the survival of trauma patients who experienced intraoperative cardiac arrest would be worse than nontrauma patients who experienced intraoperative cardiac arrest. OBJECTIVES: The aim of the present study was to compare the outcomes of trauma and nontrauma patients after intraoperative cardiac arrest. METHODS: In a tertiary university hospital and trauma centre, the intraoperative cardiac arrest cases were evaluated from January 2007 to December 2009, excluding patients submitted to cardiac surgery. Data were prospectively collected using the Utstein-style. Outcomes among the patients with trauma were compared to the patients without trauma. RESULTS: We collected data from 81 consecutive intraoperative cardiac arrest cases: 32 with trauma and 49 without trauma. Patients in the trauma group were younger than the patients in the nontrauma group (44±23 vs. 63±17, p<0.001). Hypovolaemia (63% vs. 35%, p=0.022) and metabolic/hydroelectrolytic disturbances (41% vs. 2%, p<0.001) were more likely to cause the cardiac arrest in the trauma group. The first documented arrest rhythm did not differ between the groups, and pulseless electrical activity was the most prevalent rhythm (66% vs. 53%, p=0.698). The return of spontaneous circulation (47% vs. 63%, p=0.146) and survival to discharge with favourable neurological outcome (16% vs. 14%, p=0.869) did not differ between the two groups. CONCLUSIONS: The outcomes did not differ between patients with trauma and nontrauma intraoperative cardiac arrest.

Frequency of intraoperative cardiac arrest and medium-term survival / Frequencia de parada cardiaca intraoperatoria e sobrevida no medio prazo

CONTEXT AND OBJECTIVE: Although advances in surgical and anesthetic techniques have reduced perioperative morbidity-mortality, the survival rate following cardiac arrest remains low. The aim of this study was to evaluate, over the course of one year, the prevalence of intraoperative cardiac arrest and the 30-day survival rate after this event in a tertiary teaching hospital. DESIGN AND SETTING: Prospective cohort study in a tertiary teaching hospital. METHODS: Following approval by the institutional ethics committee, anesthetic procedures and cases of intraoperative cardiac arrest between January and December 2007 were evaluated. Patients undergoing cardiac surgery were excluded. The data were gathered prospectively using the modified Utstein model, with evaluation of demographic data, pre-arrest conditions, intraoperative care, care during arrest and postoperative outcome up to the 30th day. The data were recorded by the attending anesthesiologist. RESULTS: During the study period, 40,379 anesthetic procedures were performed, and 52 cases of intraoperative cardiac arrest occurred (frequency of 13:10,000). Among these, 69% presented spontaneous return of circulation after the initial arrest, and only 25% survived for 30 days after the event. The following factors were associated with shorter survival: American Society of Anesthesiologists physical status IV and V, emergency surgery, hemorrhagic events, hypovolemia as the cause of arrest and use of atropine during resuscitation. CONCLUSIONS: Although the frequency of cardiac arrest in the surgical environment has declined and resources to attend to this exist, the survival rate is low. Factors associated with worst prognosis are more frequent in critical patients. .

CONTEXTO E OBJETIVO: Apesar de avanços nas técnicas cirúrgicas e anestésicas terem reduzido a morbimortalidade perioperatória, a taxa de sobrevivência após parada cardíaca (PC) permanece baixa. O objetivo deste estudo foi avaliar, ao longo de um ano, a incidência de PC intraoperatória e de sobrevida por 30 dias após esse evento em um hospital terciário de ensino. TIPO DE ESTUDO E LOCAL: Estudo de coorte prospectivo em hospital terci ário de ensino. MÉTODOS: Após aprovação pela Comissão de Ética institucional, os procedimentos anestésicos e os casos de PC intraoperatórios foram avaliados no período de janeiro a dezembro de 2007, excluindo-se pacientes submetidos a cirurgia cardíaca. Os dados foram coletados prospectivamente utilizando o modelo Utstein modificado, com avaliação dos dados demográficos, das condições pré-PC, dos cuidados intraoperatórios e durante a PC e do desfecho pós-operatório até o trigésimo dia. Os dados foram registrados pelo anestesiologista assistente. RESULTADOS: Durante o per íodo de estudo, 40.379 procedimentos anestésicos foram realizados, com ocorrência de 52 casos de PC intraoperatória (frequência de 13:10000). Entre estes, 69% apresentaram retorno da circulação espontânea após a primeira parada e apenas 25% sobreviveram 30 dias após o evento. Os seguintes fatores foram associados com menor sobrevida: estado físico IV e V (Sociedade Americana de Anestesiologia), cirurgias de emergência, eventos hemorrágicos, hipovolemia como causa da parada e uso de atropina durante a reanimação. CONCLUSÕES: Embora a frequência de PC no ambiente cirúrgico tenha caído e existam recursos para seu atendimento, a taxa de sobrevivência é baixa. ...