Resuscitation Following a Bupivacaine Injection for a Cervical Paravertebral Block.

BACKGROUND: Cardiac arrest related to nerve blockade using a local anaesthetic is a rare event. We report a case of bupivacaine severe cardiovascular toxicity following cervical paravertebral nerve block. CASE PRESENTATION: A 44-year-old female was admitted to Republican Vilnius University Hospital, with symptoms of sustained severe pain in her neck that radiated to both arms. Multiple cervical intervertebral hernias with spinal stenosis were confirmed by magnetic resonance imaging. Following infiltration of the subcutaneous tissue with a 0.5 % bupivacaine solution, an 18-gauge spinal needle was used to perform the paravertebral block at the C6 level. Bupivacaine was injected in incremental doses to a total of 10 mL. Rapid loss of consciousness and cardiovascular collapse suggested a neuraxial injection of bupivacaine. Long-lasting cardiopulmonary resuscitation, including chest compressions, defibrillation attempts for refractory ventricular fibrillation, medications, mechanical ventilation, and intravenous lipid emulsion infusion, was successful. No severe adverse outcomes other than acute kidney injury and chest pain related to prolonged chest compressions were documented. CONCLUSIONS: This case report emphasizes the necessity of ensuring adequate safety precautions to avoid local anaesthetic systemic toxicity. Lipid emulsion preparations should be available in all hospital settings where local anaesthetics are used for regional anaesthesia or pain management.

A mini volume loading test (mVLT) using 2.5-mLkg-1 boluses of crystalloid for indication of perioperative changes in hydration status.

BACKGROUND AND OBJECTIVE: A mini volume loading test (mVLT) evaluating hemodilution during step-wise crystalloid infusion has established that the arterio-capillary plasma dilution difference is inversely correlated to the body hydration level of subjects. This observational study aimed to test whether this can be replicated in a perioperative setting using a 2.5-mLkg-1 boluses. MATERIALS AND METHODS: The mVLT was performed before induction of regional anesthesia and 24h later. Step-wise infusion implied six mini fluid challenges. These consisted of 2.5-mLkg-1 boluses of Ringer's acetate infused during 2-3min and followed by 5-min periods with no fluids. Invasive (arterial) and noninvasive (capillary) measurements of hemoglobin were performed before and after each mini fluid challenge, as well as after a 20-min period without fluid following the last bolus. Hemoglobins were used to calculate the arterio-capillary plasma dilution difference which is used as an indication of changes in body hydration level. The 24-h fluid balance was calculated. RESULTS: Subjects were 69.5 (6.0) years old, their height was 1.62m (1.56-1.65), weight was 87.0kg (75.5-97.5) and body mass index (BMI) was 33.5kg/m2 (31.0-35.1). Preoperative arterio-capillary plasma dilution difference was significantly higher than postoperative (0.085 [0.012-0.141] vs. 0.006 [-0.059 to 0.101], P=0.000). The perioperative 24-h fluid balance was 1976mL (870-2545). CONCLUSIONS: The mVLT using 2.5-mLkg-1 boluses of crystalloid was able to detect the higher postoperative body hydration level in total knee arthroplasty patients.

A mini volume loading test for indication of preoperative dehydration in surgical patients.

BACKGROUND AND OBJECTIVE: Previously, a mini volume loading test (mVLT) detected signs of dehydration in healthy volunteers after an overnight fast. Our objective was to investigate whether mVLT could indicate preoperative dehydration in patients after an overnight fast. MATERIALS AND METHODS: The mVLT was performed in 36 elective primary total knee arthroplasty patients. Each subject received three fluid challenges before anesthesia induction. These consisted of 5 mL/kg boluses of Ringer's acetate infused over 3-5 min and followed by a 5-min period without fluids. Invasive (arterial, venous) and noninvasive (capillary) measurements of hemoglobin concentration were performed before and after each fluid challenge, as well as after a 20-min period without fluids which followed the last bolus. Arterial, venous and capillary plasma dilutions were calculated in every data point. Dilution values were used to calculate the plasma dilution efficacy of each fluid challenge. RESULTS: Venous dilution was higher than capillary after the first fluid challenge (P=0.030), but lower than capillary after 20 min period following the last bolus (P=0.009). Arterial dilution was lower than capillary (P=0.005) after 20 min following the last bolus. Veno-capillary and arterio-capillary plasma dilution efficacy differences decreased (P=0.004 and P=0.033, respectively) from positive to negative during mVLT. These are signs of re-hydration from pre-existing dehydration according to a transcapillary reflux model. CONCLUSIONS: Signs of dehydration were observed during mVLT in patients after pre-operative overnight fast. A revised transcapillary reflux model was proposed to explain the results.

The efficacy comparison of on-demand boluses with and without basal infusion of 0.1 % bupivacaine via perineural femoral catheter after arthroscopic ACL reconstruction.

PURPOSE: Optimal postoperative analgesia after anterior cruciate ligament repair remains challenging. The objective of this prospective experimental clinical study was to compare the postoperative analgesic efficacy of two infusion regimens of 0.1 % bupivacaine administered via perineural femoral catheter. METHODS: Forty adult ASA I and II patients undergoing anterior cruciate ligament reconstruction were enrolled. Surgery was performed under spinal anesthesia combined with femoral nerve block. A perineural femoral catheter was connected to the patient controlled analgesia infusion pump filled with 0.1 % bupivacaine for postoperative pain control. Subjects were assigned to one of two groups according to the bupivacaine infusion regimen: (1) 5 mL/h basal infusion with on-demand 5 mL boluses and 30-min refractive periods, and (2) only on-demand 5 mL boluses and 15-min refractive periods. Quality of postoperative analgesia, adjunctive analgesic consumption, and overall patient satisfaction were recorded for 48 h. RESULTS: Pain control was better in Group I on the day of surgery (P = 0.001) and on the first postoperative day at rest and during mobilization (P = 0.02 and P = 0.009). On the second postoperative day, only pain control during mobilization was better in Group I (P = 0.047). Adjunctive analgesic consumption and patient satisfaction were similar. CONCLUSION: Perineural femoral infusion of on-demand 5 mL boluses of 0.1 % bupivacaine combined with 5 mL/h basal infusion was more efficient than on-demand regimen alone for postoperative pain management after reconstruction of anterior cruciate ligament of the knee. LEVEL OF EVIDENCE: II.

[Actualities of adults' ventilator-associated pneumonia]. / Suaugusiuju ventiliacines pneumonijos aktualijos.

Pneumonia is the most frequently reported nosocomial infection in intensive care unit patients, predominantly in mechanically ventilated individuals. Most of the studies performed in intensive care unit settings reported the estimated 15-65% of ventilator-associated pneumonia, with high mortality rates. Ventilator-associated pneumonia results in prolonged hospitalization and increase in medical care costs. In most cases, high-risk pathogens (e.g. Gram-negative bacteria, such as Pseudomonas aeruginosa, Acinetobacter spp. and Klebsiella spp. with wide spectrum resistance, as well as methicillin-resistant Staphylococcus aureus) are the predominant causative agents of increased mortality. Occurrence of ventilator-associated pneumonia correlates with the duration of mechanical ventilation, severity of illness on admission (predicted mortality), type of admission (medical, surgical, trauma), demographical factors and treatment. Effective antibiotic management programs provide the information on local patterns of antimicrobial resistance, therefore, the proper antibiotic therapy can be chosen empirically. Invasive management strategy reduces mortality, earlier prevents organ dysfunction and lower antibiotic consumption in patients with suspected ventilator-associated pneumonia. The major goal of ventilator-associated pneumonia management is to optimize antimicrobial therapy by administering correct antibiotics in adequate doses and avoiding the initial use of wide spectrum antimicrobials. The antibiotic therapy should depend on antimicrobial sensitivity testing results and the clinical patient's response. The duration of therapy should be shortened to the minimum effective period. Excessive antibiotic use is a major factor contributing to increased antibiotic-resistance of pathogens. Prevention of the ventilator-associated pneumonia by local multidisciplinary strategies may reduce mortality rates and is beneficiary both for the patients and the hospital system. The education of the nursing staff helps to decrease the occurrence of ventilator-associated pneumonia in intensive care unit setting. However, ventilator-associated pneumonia still remains a serious controversy-generating problem in intensive care unit.