The treatment of patients with recurrent ventricular fibrillation.

During the four year period from 1972 to 1975, eleven patients, eight with recurrent and three with first attacks of ventricular fibrillation, underwent aortocoronary bypass graft and/or resection of ventricular aneurysm. All patients had old myocardial infarction from seven weeks to six years. Left ventricular angiography demonstrated discrete aneurysm of the anterior wall of the left ventricle in nine of the patients and akinesis or hypokinesis of the anterior and posterior wall of the left ventricle in the remaining two. Coronary angiography was carried out in ten patients and revealed significant disease of the left anterior descending and right coronary arteries in ten and nine patients, respectively. There was no operative mortality, and there were two late deaths. Eight patients have improved significantly and have had no further sign of ventricular irritability. The present study indicates that aortocoronary bypass graft and/or resection of ventricular aneurysm is an effective method of therapy for patients with repeacted ventricular fibrillation who have ventricular aneurysm and ischemic heart disease.     

Direct intraoperative continuous monitoring of intraocular pressure.

We present a system of intraoperative continuous monitoring of intraocular pressure (IOP) consisting of a sterilizable pressure sensor attached to a digital monitor and an analogic recording instrument. Used in conjunction with an anterior-chamber maintainer, IOP may be accurately maintained at a specific and desired level.     

Exercise response assessed by continuous monitoring of ventricular function in patients with coronary bypass operations.

The response of left ventricular function during exercise and recovery after exercise was assessed in 35 patients with coronary artery bypass grafting before and after the operation by means of a continuous ventricular function monitor, which records serial beat-to-beat radionuclide data and calculates left ventricular ejection fractions every 20 seconds. The mean ejection fraction decreased with graded bicycle exercise from 48% +/- 9% to 41% +/- 11% (p less than 0.001) before operation but increased with exercise from 50% +/- 9% to 55% +/- 11% (p less than 0.001) after operation. Cardiac response was divided into four types with respect to the profiles of the ejection fractions during exercise. Type A continued to increase; type B initially increased but then decreased in late exercise stages; type C did not change significantly; type D continued to decrease. Most patients had type C or D responses before operation but type A after operation. Seven patients with occluded grafts or ungrafted coronary arteries had type B or D responses. Three patients with complete revascularization, including an internal thoracic artery and saphenous vein grafts, had type B responses. Three patients with extensive infarction and poor left ventricular function showed type C. In the early recovery period after exercise, most patients had an "overshoot" elevation of ejection fraction. The mean value increased from 59% +/- 10% before operation to 64% +/- 11% after operation (p less than 0.01). The recovery time after exercise was reduced from 2.8 minutes before operation to 1.8 minutes after operation (p less than 0.001). The continuous ventricular function monitor elucidated changes in left ventricular function both during exercise and recovery after exercise, as well as unmasking abnormalities in left ventricular function after coronary bypass operation.     

刺激次数对术中运动诱发电位监测的影响

目的观察多次刺激模式对全麻下经颅磁刺激运动诱发电位(tcMMEPs)的影响。方法20例择期行脊髓手术的病人,在麻醉前后分别记录tcMMEPs在单次、2次和4次刺激下的波幅、潜伏期和阈值,2次和4次模式的刺激间隔均为2ms。结果麻醉后各种刺激模式的波幅都比麻醉前有极显著降低(P<0.01);但随着刺激次数的增加,波幅逐渐增大(P<0.01)。麻醉后各种刺激模式的刺激阈值都比麻醉前显著升高(P<0.01),但随着刺激次数的增加,阈值逐渐下降(P<0.01)。在麻醉后行单次刺激时,只有3例病人能引出tcMMEPs;2次刺激时有15例病人能引出tcMMEPs。在麻醉前后各刺激模式下的潜伏期都无显著变化。结论麻醉药显著抑制单次tcMMEPs的波幅,提高兴奋阈值;而2次和4次刺激在麻醉状态下能显著升高被抑制的波幅,降低兴奋阈值,部分对抗麻醉药的抑制作用,4次刺激的这种作用比2次更强。在麻醉状态下行tcMMEPs监测时应选用2次以上的刺激模式来增加监测的准确性。     

Prognostic signs during continuous monitoring of the ventricular fluid pressure in patients with severe brain injury.

The presence of CSF in cases with intracranial hypertension is a favourable prognostic sign; its absence is indicative of a progressive and potentially lethal intracranial hypertension. 2. A series of characteristic changes in the absolute value of the VFP as well as in the amplitude and rate of the cerebral pulse can provide reliable evidence of the integrity of the cerebral circulation. 3. Short-lasting disappearance of the diastolic pressure towards the end of the ultimate plateau wave and subsequent significant lowering of both the systolic and diastolic pressures is an additional bad prognostic sign.     

Pharyngeal pH monitoring in patients with posterior laryngitis.

OBJECTIVE: To evaluate the diagnostic value of 3-site 24-hour ambulatory pH monitoring in patients with posterior laryngitis (PL) and the prevalence of esophageal abnormalities in this patient group. METHODS: Twenty patients with PL and 17 healthy volunteers were studied as controls. Control subjects had transnasal esophagogastroduodenoscopy (T-EGD) and ambulatory pH monitoring. Patients underwent T-EGD, ambulatory pH monitoring, and barium esophagram. RESULTS: T-EGD documented no abnormality in controls. Esophagitis was present in 2 PL patients, and hiatal hernia in 3. Ambulatory pH monitoring showed that 15 PL patients and 2 controls exhibited pharyngeal acid reflux. Barium esophagram documented gastroesophageal reflux in 5 PL patients. However, none of these barium reflux events reached the pharynx. All PL patients with barium esophagram evidence of gastroesophageal reflux also showed pharyngeal acid reflux by pH monitoring. CONCLUSION: Pharyngeal acid reflux is more prevalent in patients with PL than in healthy controls. Patients with PL infrequently have esophageal sequelae of reflux disease. Ambulatory 24-hour simultaneous 3-site pharyngoesophageal pH monitoring detects gastroesophagopharyngeal acid reflux events in most patients with PL.     

Observations on intraoperative monitoring of visual pathways using steady-state visual evoked potentials

BACKGROUND AND OBJECTIVE: Former studies revealed conflicting information on the usefulness of intraoperative monitoring of visual evoked potentials. This study was designed to evaluate the characteristics of visual evoked potential recording in surgically anaesthetized patients using the modality of steady-state visual evoked potentials. METHODS: In 30 cases with non-cranial surgery steady-state visual evoked potentials were recorded in the awake and surgically anaesthetized patient using total intravenous anaesthesia. For stimulation, goggles with red light-emitting diodes at a frequency of 8.5 Hz were used. A two-channel recording with silver cup electrodes at Oz to Fz and Oz to earlobe was used. All traces were analysed for the presence of the characteristically sinusoidal waveform and amplitudes and latencies of the main peaks were measured. RESULTS: Recordings during surgery demonstrated a minor latency prolongation of 16% and a more pronounced amplitude attenuation of 67% compared to the recordings in the awake patients. These differences were statistically significant (paired t-test, P < 0.001). In surgically anaesthetized patients steady-state visual evoked potentials showed a relatively high intra- and interindividual variability. In four of 30 patients completely stable recordings were obtained, whereas in 14 patients identifiable waves were recordable in only less than 50% of the intraoperative traces. Of the total 1360 traces recorded intraoperatively clearly identifiable steady-state visual evoked potentials patterns were present in 56% of the traces. There was no correlation between the magnitude of the evoked potential amplitude and its stability in intraoperative recordings. CONCLUSIONS: We conclude from this study, that steady-state visual evoked potential recordings in the surgically anaesthetized patient appeared to be more stable compared to our earlier findings using transient visual evoked potentials. However, further efforts are necessary to improve the stability of the recordings during surgery and thus allow for a more reliable intraoperative monitoring of visual pathways in routine clinical practice.     

The deleterious effects of intraoperative hypotension on outcome in patients with severe head injuries.

Prehospital or admission hypotension doubles the mortality for patients with severe head injury (SHI = Glasgow Coma Scale score less than or equal to 8). To our knowledge no study to date has determined the effects of intraoperative hypotension [IH: systolic blood pressure (SBP) less than 90 mm Hg] on outcome in patients with SHI. This study examined 53 patients who had SHI and required early surgical intervention (surgery within 72 hours of injury). All patients were initially normotensive on arrival. There were 17 patients (32%) who developed IH and 36 (68%) who remained normotensive throughout surgery. The mortality rate was 82% in the IH group and 25% in the normotensive group (p less than 0.001). The duration of IH was inversely correlated with Glasgow Outcome Scale using linear regression (R = -0.30; p = 0.02). Despite vigorous fluid resuscitation in the IH group, additional pharmacologic support was used in only 32%. These data suggest that IH is not uncommon after SHI (32%) and that it does have a significant effect on patient outcome.     

麻醉时间对运动诱发电位监测的影响

目的 观察麻醉时间对经颅磁刺激运动诱发电位(tcMMEPs)参数的影响.方法 20例择期行脊髓手术的病人,在手术前日、麻醉前、麻醉后30、60、90、120、150,180和210 min及麻醉结束后3 h分别记录tcMMEPs的波幅、潜伏期以及麻醉持续时间.结果 麻醉时间平均为4.4 h.波幅的术前值和基础值比较差异无统计学意义.麻醉后各时点的波幅比基础值显著降低(P＜0.01);麻醉后180 min的波幅比之前各时点降低(P＜0.01),并维持到麻醉结束后3 h.各时点的潜伏期差异无统计学意义.结论 麻醉药对tcMMEPs的抑制作用在长时间麻醉后逐渐增大,导致tcMMEPs的波幅下降,手术中应用tcMMEPs监测脊髓运动功能时应当充分考虑这种现象.     

Feasibility of intraoperative continuous glucose monitoring: An observational study in general surgery patients

BackgroundPerioperative hyperglycemia is associated with adverse outcomes in surgical patients, and major societies recommend intraoperative monitoring and treatment targeting glucose <180–200 mg/dL. However, compliance with these recommendations is poor, in part due to fear of unrecognized hypoglycemia. Continuous Glucose Monitors (CGMs) measure interstitial glucose with a subcutaneous electrode and can display the results on a receiver or smartphone. Historically CGMs have not been utilized for surgical patients. We investigated the use of CGM in the perioperative setting compared to current standard practices.MethodThis study evaluated the use of Abbott Freestyle Libre 2.0 and/or Dexcom G6 CGMs in a prospective cohort of 94 participants with diabetes mellitus undergoing surgery of ≥3 h duration. CGMs were placed preoperatively and compared to point of care (POC) BG checks obtained by capillary samples analyzed with a NOVA glucometer. Frequency of intraoperative blood glucose measurement was at the discretion of the anesthesia care team, with a recommendation of once per hour targeting BG of 140–180 mg/dL. Of those consented, 18 were excluded due to lost sensor data, surgery cancellation, or rescheduling to a satellite campus resulting in 76 enrolled subjects. There were zero occurrences of failure with sensor application. Paired POC BG and contemporaneous CGM readings were compared with Pearson product-moment correlation coefficients, and Bland-Altman plots.ResultsData for use of CGM in perioperative period was analyzed for 50 participants with Freestyle Libre 2.0, 20 participants with Dexcom G6, and 6 participants with both devices worn simultaneously. Lost sensor data occurred in 3 participants (15%) wearing Dexcom G6, 10 participants wearing Freestyle Libre 2.0 (20%) and 2 of the participants wearing both devices simultaneously. The overall agreement of the two CGM's utilized had a Pearson correlation coefficient of 0.731 in combined groups with 0.573 in Dexcom arm evaluating 84 matched pairs and 0.771 in Libre arm with 239 matched pairs. Modified Bland-Altman plot of the difference of CGM and POC BG indicated for the overall dataset a bias of −18.27 (SD 32.10).ConclusionsBoth Dexcom G6 and Freestyle Libre 2.0 CGMs were able to be utilized and functioned well if no sensor error occurred at time of initial warmup. CGM provided more glycemic data and further characterized glycemic trends more than individual BG readings. Required time of CGM warm up was a barrier for intraoperative use as well as unexplained sensor failure. CGMs had a fixed warm of time, 1 h for Libre 2.0 and 2 h for Dexcom G6 CGM, before glycemic data obtainable. Sensor application issues did not occur. It is anticipated that this technology could be used to improve glycemic control in the perioperative setting. Additional studies are needed to evaluate use intraoperatively and assess further if any interference from electrocautery or grounding devices may contribute to initial sensor failure. It may be beneficial in future studies to place CGM during preoperative clinic evaluation the week prior to surgery. Use of CGMs in these settings is feasible and warrants further evaluation of this technology on perioperative glycemic management.     

The importance of monitoring intramyocardial temperature during hypothermic myocardial protection.

In 50 patients undergoing cardiac operation, hypothermic cardioplegic solution was infused into the root of the aorta immediately after aortic cross-clamping. Cardiac standstill was achieved within 1 to 3 minutes. However, monitoring of intramyocardial temperature with a needle thermistor revealed that such core cooling is unpredictable (the intramyocardial temperature achieved ranged from 7 degrees to 33 degrees C), unstable (this temperature can rise at more than 0.5 degrees C per minute), and uneven (a difference of up to 17 degrees C was observed between the intramyocardial temperature of the anterior and posterior left ventricular sites). The area supplied by the stenotic coronary artery was least protected. Monitoring of intramyocardial temperature enables one to know when supplementary cooling is indicated. We conclude that widespread differences in this temperature during cardiac operation make monitoring advisable for optimal myocardial protection.     

Improved myocardial preservation with oxygenated cardioplegic solutions as reflected by on-line monitoring of intramyocardial pH during arrest

To examine the relationship between intramyocardial pH during global ischemic arrest and subsequent functional and biochemical recovery, 40 canine hearts were subjected to 4 hours of arrest at 10 degrees C. Four groups, each containing 10 hearts, were differentiated by the oxygen concentration of a hyperkalemic crystalloid cardioplegic solution (CCS), which was infused every 20 minutes. In group 1 the CCS was equilibrated at 4 degrees C with nitrogen to remove oxygen. In group 2 the CCS was aerated at 4 degrees C. In group 3 the CCS was treated to achieve an oxygen tension (PO2) similar to group 2 but with a reduced nitrogen content to prevent bubble formation, which is theoretically possible during reperfusion ("myocardial bends"). In group 4 the CCS was fully oxygenated at 4 degrees C. The resulting PO2 of CCS measured at 10 degrees C was less than 20, 170, 170, and 750 mm Hg in groups 1, 2, 3, and 4, respectively. Left ventricular function (LVF) was assessed from function curves at constant mean aortic pressure and heart rate. Functional recovery, expressed as a percentage of prearrest LVF, was 38.1% +/- 10.7% in group 1 and 84.0% +/- 8.1% in group 4 (p less than 0.008). Functional recovery was 64.9% +/- 5.5% and 69.1% +/- 7.0% in groups 2 and 3, which had similar PO2. Differences in recovery between groups 2 and 3 and group 1 approached statistical significance (p less than 0.05, NS). The mean-integrated intramyocardial pH during arrest was higher (p less than 0.003) in group 4 (7.14 +/- 0.05) than in group 1 (6.84 +/- 0.06) or group 2 (6.86 +/- 0.07). The minimum intramyocardial pH during arrest was higher in group 4 than in any other group (p less than 0.002). Myocardial adenosine triphosphate concentration at the end of arrest, expressed as a percentage of its prearrest value, was highest in group 4 (75.9% +/- 8.1%) and lowest in group 1 (54.3% +/- 5.7%), a difference approaching statistical significance (p less than 0.05, NS). These data suggest that the measurement of intramyocardial pH is a useful on-line indicator of the adequacy of preservation during hypothermic arrest and that excess nitrogen in aerated CCS had little or no effect on recovery. The data confirm the hypothesis that oxygenation of CCS is associated with good myocardial preservation, which may be attributed to the provision of oxygen for the support of aerobic metabolism during arrest.     

术中持续与间断神经监测技术在腔镜辅助甲状腺手术中的对比研究

目的对比持续术中神经监测(C－IONM)和间断性术中神经监测(I－IONM)在腔镜辅助甲状腺手术中的临床效果。 方法回顾性分析2016年5月至2018年12月59例接受腔镜辅助甲状腺手术的患者资料,根据不同术中神经监测方式分为C－IONM组和I－IONM组。采用SPSS 21.0统计软件进行分析,迷走神经及喉返神经功能评估采用( ±s)表示,行独立t检验;喉返神经损伤情况行χ²检验。P<0.05为检验标准。 结果两组术中神经监测时间差异无统计学意义(P>0.05)。59例患者共解剖显露喉返神经86条,其中11条术中出现肌电图( EMG)振幅下降>50%,且在停止手术操作后10 min内均逐渐恢复至初始R1信号水平的70%以上,平均恢复时间为(6.7±2.5) min,两组患者术中喉返神经损伤及恢复情况差异无统计学意义(P>0.05)。两组患者术毕时EMG振幅和潜伏期较同组APS电极刺激初始时变化差异无统计学意义(P>0.05)。光镜下两组迷走神经和喉返神经结构正常,纤维细胞完整,无神经束水肿及神经内血管损伤发生。 结论腔镜辅助甲状腺手术中C－IONM技术和I－IONM技术在降低迷走神经和喉返神经损伤方面疗效近似,两种神经监测技术对患者神经功能变化无影响,均安全可靠。     

大手术后危重病人连续监测胃粘膜pH值的临床研究

目的 探讨大手术后危重患者胃粘膜pH值(pHi)的变化与预后及并发症的关系。方法 对63例大手术后危重患者收入ICU,在 12、24、48、72 h连续监测 pHi的变化,存活者随访至出院,死亡者至临终状态。结果 与 11例死亡病人比较,52例存活者中 pHi降低明显为少,25％比 100％,存活者 pHi正常明显居多,75％比 0,P<0.01,pHi以 7.35为界值,低于此值不正常。存活组:pHi<7.35(含先正常后低)13例,并发症 10例(10/13),pHi>7.35(含先低后正常)39例,并发症 17例(17/39)。死亡组:pHi<7.35并呈持续降低 9例,先正常后降低 2例。对 pHi总减低者其死亡预测的敏感性为 100％,特异性为75％,准确性为88％,预测并发症的阳性率为76.9％。结论 连续监测pHi的变化其预测病死率的准确性较高,pHi异常者术后并发症发生率高。