Impossible mask ventilation after an unusually low dose fentanyl-induced muscle rigidity in a patient with essential tremor: a case report and review of the literature.

Although opioid-induced muscle rigidity occurs more commonly with large doses and rapid administration of the drugs, there is a number of cases reported, where muscle rigidity was experienced with lower doses of opioids. We present and discuss a case of muscle rigidity induced by an unusually low dose of fentanyl as primary agent during induction of anesthesia. A 79 year old male patient, scheduled for hernia repair, and with a preoperative physical examination of slight hand tremor, received a bolus of 100 mcg (1.2 mcg/kg) fentanyl as primary agent for induction. About 40 sec later he stopped responding, lost consciousness and developed neck and masseter muscle spasm with jaw closure and thoracoabdominal rigidity. Blood pressure was increased significantly. Ventilation was impossible. Rapid oxygen desaturation led us to proceed with IV propofol 150 mg and suxamethonium 100 mg. Opioid-induced muscle rigidity may cause life-threatening respiratory compromise and should be readily recognized and treated by anesthesiologists.

Changes in arterial blood flow of free flaps after the administration of sildenafil in swine.

We evaluated blood flow changes after experimental free tissue transfer and the potential hemodynamic effect of sildenafil on the free flap. Sixteen swine were used for free transfer of a latissimus dorsi myocutaneous flap to the chest that was anastomosed to the internal mammary vessels, and were randomized into controls and study group. The latter received a single dose of sildenafil, 6 hours following flap revascularization. Doppler ultrasonography revealed that arterial flow was mainly systolic postoperatively. Diastolic flow patterns were gradually restored after the first postoperative day. Pulsatility index (PI) significantly increased and flow volume decreased in all animals postoperatively. In the sildenafil group, PI significantly decreased and flow volume increased, while diastolic flow patterns were restored earlier on compared to controls, postoperatively. In conclusion, the administration of sildenafil after free tissue transfer increases flow volume and facilitates the restoration of diastolic blood flow patterns in the early critical postoperative period.

Foucher first dorsal metacarpal artery flap versus littler heterodigital neurovascular flap in resurfacing thumb pulp loss defects.

Our study aims to illustrate the advantages and disadvantages of Foucher's first dorsal metacarpal artery flap and Littler's heterodigital neurovascular flap in thumb pulp reconstruction, by assessing wound healing of donor and recipient sites, sensibility, and functional outcome of the reconstructed thumb. Fourteen male patients were reconstructed either with Foucher (n = 8) or Littler flap (n = 6). Dissection of Foucher's flap was faster than that of Littler's flap. All Littler flaps survived completely, but we experienced 1 partial Foucher flap necrosis. Thumb motility and stability was optimal in all patients. Wound healing of donor sites was achieved in both groups. Two patients reconstructed with Littler flap developed scar contractures and presented a reduced range of motion of donor finger and first webspace, respectively. Although Littler flap resulted in better sensibility and tactile gnosis of the reconstructed thumb-pulp, Foucher flap ensured negligible donor site morbidity, complete cortical reorientation, and better overall hand function.

Evaluation of an intraoperative algorithm based on near-infrared refracted spectroscopy monitoring, in the intraoperative decision for shunt placement, in patients undergoing carotid endarterectomy.

BACKGROUND: We evaluated whether the use of an intraoperative algorithm based on cerebral oximetry with near-infrared refracted spectroscopy (NIRS) monitoring, could aid in the intraoperative decision for shunt placement, in patients undergoing carotid endarterectomy (CEA). METHODS: In this prospective, randomized, controlled study were included 253 patients who underwent CEA under general anesthesia. They were randomly allocated in Group A (n=83) using NIRS monitoring and the suggested algorithm, Group B (n=84) using NIRS monitoring without the algorithm and Group C (n=86) who served as controls. Shunt placement criterion for Group A and B was 20% drop in ipsilateral regional saturation from the baseline value recorded before surgery. Primary endpoint of the study was to evaluate the use of the intraoperative algorithm based on NIRS monitoring, in the intraoperative decision for shunt placement, in patients undergoing carotid endarterectomy. Additionally, we examined whether this might affect the rate of postoperative neurologic deficits. RESULTS: When compared with Group A, Group B and Group C had 3.7 times (99% c.i. 1.5-9.5) and 70.6 times (99% c.i. 15-724.3) respectively, greater likelihood of having a shunt placed. When compared with Group B, Group C had 19.4 times (99% c.i. 4.3-191.2) greater likelihood of having a shunt placed. Regarding the rate of postoperative neurologic deficits no significant difference was found between the three groups. CONCLUSIONS: The use of a specific algorithm based on NIRS monitoring, in patients undergoing CEA, may aid in the intraoperative decision for shunt placement.

Portable duplex ultrasonography: A diagnostic and decision-making tool in reconstructive microsurgery.

Unidirectional Doppler is a common diagnostic tool by the Reconstructive Microsurgeons; however, it may generate false signals and surely provides less imaging data as compared to duplex ultrasonography. We have reviewed the use of Portable Duplex Ultrasonography (PDU) in 16 patients who underwent complex soft-tissue/bone reconstruction, aiming to determine its role in the design and management of free tissue transfer. According to our data, there were modifications either of the surgical plan and/or of patient's management, based on PDU findings, in 10 out of 16 patients (62.5%). The use of ultrasound directed to subtle modifications in three patients (19%), but to significant changes of the surgical plan in four patients (25%). Also, the use of ultrasound improved significantly the postoperative management in three patients (19%). Thus, significant impact of PDU in patient's treatment was recorded in 44% of cases. Portable ultrasound represents generally available method for preoperative, intraoperative, and postoperative diagnosis and decision-making in free tissue transfer, hence could replace in the near future the unidirectional Doppler in the hands of Microsurgeons.

Comparison of standard polyvinyl chloride tracheal tubes and straight reinforced tracheal tubes for tracheal intubation through different sizes of the Airtraq laryngoscope in anesthetized and paralyzed patients: a randomized prospective study.

BACKGROUND: The authors compared the intubation success rate of straight reinforced tracheal tubes emerging from the Airtraq laryngoscope (Prodol Meditec S.A., Vizcaya, Spain) with standard preformed polyvinyl chloride tracheal tubes in anesthetized patients. METHODS: The authors randomly allocated 347 adult patients to be intubated with standard polyvinyl chloride tracheal tubes, standard straight wire-reinforced tracheal tubes, or silicone straight wire-reinforced tubes, through either the larger or the smaller adult laryngoscope sizes. The possible influence of laryngoscope size, tube size, and tube type on intubation failure was examined. RESULTS: Success rates were 100% for polyvinyl chloride tracheal tubes, 78.5% for standard wire-reinforced tracheal tubes, and 75.4% for silicone wire-reinforced tubes (P < 0.01). Compared with the former, patients in the straight standard and silicone wire-reinforced tube groups required more optimization maneuvers (4.1% vs. 42.1%; P < 0.01) and more attempts at successful intubation (0% vs. 7.3%; P < 0.01). The angle created by the tube emerging from the Airtraq guiding channel was inversely correlated to the ratio of the endotracheal tube OD to the width of the channel in the standard and silicone wire-reinforced tube groups (r = -0.95 and r = -0.82, respectively; P < 0.01). Finally, a decrease in 0.1 of the above ratio was associated with a 3.1 (95% confidence interval, 1.9-5.2; P < 0.01) times increase in the odds ratio of intubation failure. CONCLUSIONS: Standard polyvinyl chloride tracheal tubes were found to be superior compared with standard and silicone straight wire-reinforced tubes for intubation through the Airtraq laryngoscope. In the latter groups, a decrease of the ratio of their OD to the width of the Airtraq guiding channel resulted in increased intubation failure.

Upper cervicothoracic sympathetic block increases blood supply of unipedicled TRAM flap.

A prospective clinical study was conducted to evaluate the impact of upper cervicothoracic sympathetic block (CTGB) on blood supply of the unipedicled transverse rectus abdominis musculocutaneous (TRAM) flap. The use of the technique is first reported herein, as a manipulation improving arterial blood flow within the flap in high-risk patients, thus reducing postoperative morbidity. From March 2003 to September 2006, 28 heavy smokers, who underwent delayed breast reconstruction with unipedicled TRAM flap, were included in the study. Intraoperative upper cervicothoracic block (ganglia C5,6,7 and T1,2) was performed in 16 patients (group A), while 12 patients, who did not consent to have the blockade (group B), were the control. Clinical evaluation and thermographic monitoring of skin temperature, using the Thermacam A40 (FLIR systems, Wilsonville, OR), was used in all patients and determined the blood flow within the flap. All patients were monitored for early and late complications. In all group A patients, CTGB resulted in TRAM flap temperature increase within 9.5 to 16 min. Flap temperature elevation was found to be significantly higher (P < 0.001) and hospital stay was significantly shorter (P = 0.004) in group A patients. No CTGB or TRAM flap complications were recorded in group A patients. However, in group B, major fat necrosis occurred in 2 patients and partial (1/3) flap necrosis in 1 patient. Upper cervicothoracic sympathetic block is a reliable, safe, and useful technique for increasing blood flow within TRAM flaps in high-risk patients, like heavy smokers, and it minimizes postoperative morbidity.