We present a case of paradoxical gas embolism during CO2 insufflation in laparoscopic nephrectomy for a huge renal angiomyolipoma. Paradoxical CO2 embolism in the left heart chambers without demonstrable intracardiac right-to-left shunt was detected by transesophageal echocardiography (TEE). The surgical procedure was stopped immediately, but the patient recovered with mild neurologic deficit. We speculate that rapid pneumoperitoneum introduction pushed CO2 into the abnormal vasculature of the angiomyolipoma, which communicates with the systemic vascular system, causing pseudoaneurysm formation. Follow-up abdominal computed tomography showed a new pseudoaneurysm inside the tumor. If intracardiac right-to-left shunt is excluded for the reason of paradoxical gas existence, there remains extracardiac right-to-left shunt, with transpulmonary passage of the venous emboli being the most likely mechanism. In fact, the cause of paradoxical gas embolism in this case remains unknown. Therefore, laparoscopic surgery for huge angiomyolipoma should be performed with extreme caution; an open procedure may be considered as an alternative.

The reduced Greco model had the lowest objective function value and AICc and thus the best fit. This model was reliable with acceptable predictive ability based on adequate clinical correlation. We suggest that this model has practical clinical value for patients undergoing procedures with varying degrees of stimulation.

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There is still no consensus on how to determine the dose of spinal anaesthesia with adequate sensory block for a planned surgery. This retrospective study aimed to explore the associations of miscellaneous factors with peak sensory block level after spinal anaesthesia with hyperbaric bupivacaine, and to construct a predictive model for single-shot spinal anaesthesia. We collected the records of 401 non-pregnant adults who underwent spinal anaesthesia with 0.5% hyperbaric bupivacaine at the L3–4 or L4–5 intervertebral space for lower body surgeries. Multiple linear regression analysis was used to investigate predictors of the block level and build up the predictive model. Five variables were identified as independent predictors of the peak sensory block level, including bupivacaine dose, height, weight, gender and age. The predictive model for peak block level after spinal anaesthesia could be expressed as a formula with these five variables and the estimated predictive power was 0.72. Based on this model, it is possible to determine a reasonable dose of hyperbaric bupivacaine for spinal anaesthesia, which gives adequate sensory block required for diverse surgical procedures in various patients and could be considered as a dose reference for sensory block height in spinal anaesthesia.