Local anesthetic spread into the paravertebral space with two types of quadratus lumborum blocks: a crossover volunteer study.

PURPOSE: Previous work showed that 20 mL of local anesthetic (LA) did not spread into the paravertebral space (PVS) via the intramuscular quadratus lumborum block (QLBi). If spread of LA into the PVS can be achieved by increasing the total LA volume, QLBi can be more effective. We hypothesized that a larger volume of LA for the QLBi would spread into the PVS. METHODS: This crossover volunteer study included five healthy men. For comparison, both the ultrasound-guided QLB type 2 (QLB2) and QLBi were employed on opposite sides of each volunteer, and the spread of LA solution (0.7 mL/kg) mixed with contrast media in the PVS was assessed 1 h after the first injection using magnetic resonance imaging. Sensory loss was evaluated by pinprick 90 min post-injection. Each volunteer underwent both QLB types, and the same procedures were administered on opposite sides 7 days after the first experiment. RESULTS: In total, 20 QLB blocks (10 QLB2 and 10 QLBi) were performed. LA did not spread into the PVS after the QLBi. The sensory block area included the lower abdomen after the QLB2, but not after the QLBi. The sensory block area did not extend to the upper abdominal region or the midline of the lower abdomen with either block method. CONCLUSION: LA administered by the QLB2 spreads into the PVS of T10-T12, resulting in lower and lateral abdominal sensory loss. In contrast, LA administered by the QLBi does not spread into the PVS and results in only lateral abdominal sensory loss.

A randomized controlled trial comparing paravertebral block via the surgical field with thoracic epidural block using ropivacaine for post-thoracotomy pain relief.

PURPOSE: We conducted a comparative study to evaluate analgesic efficacy between paravertebral block via the surgical field (PVB-sf), in which the catheter was inserted into the ventral side of the sympathetic trunk in the paravertebral space by a thoracic surgeon under thoracoscopic visualization, and epidural block (Epi) using ropivacaine for post-thoracotomy pain relief. METHODS: Lung cancer patients scheduled for lobectomy via thoracotomy were randomly allocated to receive either PVB-sf or Epi (n = 36 per group). Before thoracotomy closure, 0.375% ropivacaine was administered as a bolus (PVB-sf, 20 mL; Epi, 5 mL), followed by a 300-mL continuous infusion of 0.2% ropivacaine at 5 mL/h. Postoperative pain was assessed using a visual analog scale (VAS) score at various time points, including the primary endpoint of 2 h after ropivacaine bolus injection. Sensory block area, vital signs, serum ropivacaine concentrations, and side effects were also evaluated. RESULTS: The Epi group showed significantly lower VAS scores and blood pressure and a wider sensory block area than the PVB-sf group at all evaluation time points. While the mean serum ropivacaine concentration in the PVB-sf group was significantly higher than that in the Epi group until 1 h after injection of the ropivacaine bolus, there was no significant difference at any subsequent assessment point. The incidence of side effects was similar between the groups. CONCLUSION: The Epi was superior to PVB-sf for the management of post-thoracotomy pain in this patient cohort. The number of dermatomes anaesthetized by Epi was greater than that anaesthetized by PVB-sf. No difference in complication rates was observed between the two groups.

Incidence rate of chronic pain after 1.5-2 years of thoracotomy between paravertebral block versus epidural block: a cohort study.

Paravertebral block and epidural block are frequently employed for post-thoracotomy pain relief. It is not clear which postoperative analgesia method is effective for the chronic pain after the postoperative long term progress. Our hypothesis was that paravertebral block would be more effective than epidural block for chronic pain 1.5-2 years after thoracotomy. A cohort study investigating postoperative pain was performed in lung cancer patients undergoing thoracotomy between the ages of 20-80 year-old, employed for another randomized controlled trial. In previously study, the patients were randomly allocated into either the epidural block or paravertebral block group (n = 36/group). Patients in each group received the respective block placement with continuous 0.2% ropivacaine infusion at 5 ml/h. The patients completed a telephone observational survey using the EQ-5D-5L at 1.5-2 years. Forty-eight patients, 23 in the epidural block group and 25 in the paravertebral block group, were included in the final analysis. Quality of life scores at 1.5-2 postoperative years was similar in both groups. Mean scores ± standard deviation and 95% confidence interval were 0.899 ± 0.081 (0.705-0.938) in the epidural block group and 0.905 ± 0.079 (0.713-0.938) in the paravertebral block group, respectively, p = 0.81. The incidence rate of chronic postsurgical pain was eight patients; four in the epidural block group (17.4%) and four in the paravertebral block group (16.0%). There was no difference in incidence rate of long-term chronic postsurgical pain at 1.5-2 years after thoracotomy between the both groups. Our result will be used for further study protocols.

Coagulation ability when separating from cardiopulmonary bypass with and without fresh frozen plasma: a pilot study.

OBJECTIVE: Several strategies are employed for administering fresh frozen plasma (FFP) during weaning from cardiopulmonary bypass (CPB). This study evaluated by coagulation function aimed to compare two strategies of administering FFP in cardiovascular surgery: administering 4 units of FFP before separating from CPB or administering it after weaning from CPB. METHODS: Thirty patients who underwent CPB and were expected to receive 8 units of FFP and 20 units of platelet concentrate were randomly allocated into group A (8 units of FFP and 20 units of platelet concentrate administered after separating from CPB) and group B (4 units of FFP administered before separation, and 4 units of FFP and 20 units of platelet concentrate administered after separating from CPB). Thromboelastography (TEG6s®, HAEMONETICS Japan GK, Tokyo, Japan) was conducted at four time points before and after separation. Blood test results, blood loss, and required amounts of blood transfusion were compared. The primary outcome was the difference in coagulation function evaluated by TEG6s 90 min after protamine administration. RESULTS: Twenty-eight patients were enrolled in the study. Coagulation function after separating from CPB was not significantly different between the groups. Additionally, no significant differences were found in intensive care unit outcomes, such as 24-h transfusion requirements. CONCLUSIONS: Coagulation function 90 min after separating from CPB was not significantly different between the groups. Prior FFP administration before separation did not provide significant improvement in coagulation function.

Comparison between rectus sheath block with 0.25% ropivacaine and local anesthetic infiltration with 0.5% ropivacaine for laparoscopic inguinal hernia repair in children.

This randomized, observer-blinded prospective study aimed to compare the postoperative analgesic effects of ultrasound-guided rectus sheath block with those of local anesthetic infiltration of the surgical field in children undergoing inguinal hernia repair. Children aged 2 to 14 years, scheduled for elective single-incision laparoscopic percutaneous extraperitoneal closure, were randomly allocated to receive ultrasound-guided rectus sheath block (group R) or local anesthetic infiltration of the surgical field (group L). In group R, 0.5 ml/kg of 0.25% ropivacaine (per side) was administered after intubation. In group L, 0.4 ml/kg of 0.5% ropivacaine was administered after peritoneal closure. Postoperative pain was assessed using the Face Scale and Face, Legs, Activity, Cry, Consolability scale at various time points, including the primary endpoint of 2 h after leaving the operation room. Additional analgesic drugs were used according to the Face Scale scores. Patient characteristics, the amount of additional drugs, and complication rate were evaluated in both groups. The patient and surgical characteristics were comparable between groups. The Face Scale and Face, Legs, Activity, Cry, Consolability scale scores were not significantly different between group R (n = 38) and group L (n = 38) at 2 h after leaving the operation room. The amount of additional drugs administered at 2 h after leaving the operation room were also comparable between groups. Our findings suggest that the postoperative analgesic efficacy of ultrasound-guided rectus sheath block is not superior to that of local anesthetic infiltration of the surgical field for pediatric single-incision laparoscopic percutaneous extraperitoneal closure.

Incidence of reexpansion pulmonary edema in minimally invasive cardiac surgery.

Minimally invasive cardiac surgery requires fewer blood transfusions and mediastinitis is less frequently observed compared to conventional median sternotomy surgical intervention, and it leads to earlier recovery and discharge. However, once reexpansion pulmonary edema occurs, the patient requires long-term management in the intensive care unit. This retrospective study was performed to investigate the incidence of reexpansion pulmonary edema in minimally invasive cardiac surgery. Patients who underwent minimally invasive cardiac valve surgery using cardiopulmonary bypass and port-access by a minimal right lateral thoracic incision between January 2010 and January 2018 were enrolled in this single-center retrospective study, which was approved by the institutional review board of Japanese Red Cross Nagoya Daiichi Hospital (Nagoya, Japan), and the requirement for written informed consent was waived. All data were collected from electronic charts. The primary outcome was the incidence rate of reexpansion pulmonary edema in patients undergoing minimally invasive cardiac surgery. A total of 662 patients underwent minimally invasive cardiac surgery, and we analyzed 651 of these cases. No case of reexpansion pulmonary edema was observed in this study. The statistically-calculated incidence rate of reexpansion pulmonary edema was less than 0.6% (95% confidence interval: 0.0-0.6). The incidence of cerebral infarction was 0.92% (n = 6). Intensive care unit stay days, hospital stay days after surgery, and the death rate after 30 days were 1.5 ± 2.0 days, 9.6 ± 3.9 days, and 0.15%, respectively. Although there was no incidence of clinical reexpansion pulmonary edema in this study, the predicted incidence of reexpansion pulmonary edema by statistical analysis was less than 0.6%.

[Anesthetic management of cesarean section in a patient with pulmonary embolism due to protein S deficiency diagnosed postoperatively].

A 27-year-old pregnant woman with pulmonary embolism was scheduled for cesarean section. She received anticoagulant therapy with continuous infusion of heparin and prophylactic placement of an inferior vena cava (IVC) filter. Heparin was discontinued 7 hours before operation. Spinal anesthesia using hyperbaric bupivacaine 12 mg was performed and the operation was completed uneventfully. She was given a diagnosis of protein S deficiency after discharge. Preoperative anticoagulant therapy and placement of IVC filter may be effective in preventing new pulmonary embolism.

Mitral valve repair in infective endocarditis during pregnancy.

Infective endocarditis (IE) during pregnancy and subsequent cardiac surgery are rare and associated with a high risk of mortality for the mother and fetus. It is difficult to determine the right time for cardiac intervention when IE is diagnosed early in pregnancy. A 33-year-old previously healthy woman in the 11th week of pregnancy was diagnosed with IE and underwent surgical intervention. The cardiopulmonary bypass settings and the anesthetic drugs were carefully chosen. Although she was in good health, while being discharged, the fetus did not survive. Anesthesiologists prioritizing the mother's survival should aim to improve fetal outcomes in such cases.

Spread of Quadratus Lumborum Block to the Paravertebral Space Via Intramuscular Injection: A Volunteer Study.

BACKGROUND AND OBJECTIVES: Several types of quadratus lumborum block (QLB) are used for postoperative analgesia and are believed to be effective against both somatic and visceral pain via a local anesthetic (LA) effect in the paravertebral space (PVS). However, it remains unclear whether all QLB techniques result in LA spread into the PVS. We hypothesized that LA administered via intramuscular QLB would spread into the paravertebral space and investigated the spread and sensory block area of LA in intramuscular QLB. METHODS: This volunteer study included 5 healthy men and 1 woman, with no previous medical history. Intramuscular QLB and lateral transversus abdominis plane block were performed under real-time ultrasound guidance for comparison of sensory deprivation range. Two days later, the same procedure was performed on the contralateral side of the body. The spread of LA via intramuscular QLB spread to the PVS was assessed 1 hour after the first injections using magnetic resonance imaging. Sensory perception was also evaluated by the pinprick test at 90 minutes after injection. RESULTS: In total, we performed 11 intramuscular QLBs and 11 lateral transversus abdominis plane blocks. Magnetic resonance imaging showed that LA did not spread into the PVS after ultrasound-guided intramuscular QLB. The analgesic area corresponded to the side of the body that was ipsilateral to the block. CONCLUSIONS: Ultrasound-guided intramuscular QLBs are not clinically useful for procedures requiring LA spread into the PVS but do result in an ipsilateral analgesic effect in healthy volunteers. CLINICAL TRIAL REGISTRATION: This study was registered at University Hospital Medical Information Network Clinical Trials Registry, UMIN 000019149.

[Anesthetic management of a patient with mitochondrial encephalomyopathy under total intravenous anesthesia].

This report describes a patient with mitochondrial encephalomyopathy who underwent tracheostomy under total intravenous anesthesia. This 15-year-old girl had been suffering from aspiration pneumonia repeatedly. Anesthesia was induced with propofol (30 mg) and fentanyl (50 microg), and the trachea was intubated without a muscle relaxant. The patient was mechanically ventilated also without a relaxant, and anesthesia was maintained with a continuous infusion of propofol 4-10 mg x kg(-1) x hr(-1) and a bolus injection of fentanyl 25 microg. Bispectral index (BIS) was monitored and maintained at 15-65. The patient showed smooth recovery from anesthesia, and the BIS value returned to the pre-anesthetic level 15 minutes after completion of the anesthesia. Her postoperative course was uneventful. We conclude that total intravenous anesthesia by propofol and fentanyl is a preferable method for the management of the patient with mitochondrial encephalomyopathy.