A Comparison of Peripheral Skin Blood Flow and Temperature During Endoscopic Thoracic Sympathotomy

Evaluation of blood perfusion using laser doppler flowmetry during endoscopic lumbar sympathectomy in patients with plantar hyperhidrosis: a retrospective observational study

The purpose of this study is to evaluate whether monitoring the changes of skin blood flow may be effective in assessing blood perfusion during endoscopic lumbar sympathectomy (ELS) in patients with plantar hyperhidrosis. In this study, a total of 30 patients who underwent surgical treatment for plantar hyperhidrosis at the Department of Thoracic and Cardiovascular Surgery in Yonsei University Gangnam Severance Hospital, Seoul, Korea, between July 2020 and December 2020, were retrospectively analyzed. Sympathetic denervation was performed on the third lumbar ganglion, and intraoperative laser doppler flowmetry (LDF) was used to detect the lumbar sympathetic chain accurately. We observed an abrupt increase of peripheral blood flow after sympathetic denervation, and the median percent changes of perfusion unit were 173.27 (inter-quartile range, IQR 195.48) and 392.98 (IQR 597.27) for the left and right sympathectomies, respectively. This study demonstrated the efficacy of monitoring skin blood flow via LDF during ELS. This result suggests that exact detection of blood flow using LDF is essential for improving the accuracy of ELS by checking the perfusion site on the sole in patients with plantar hyperhidrosis.

Assessment of skin temperature during regional anaesthesia-What the anaesthesiologist should know

Body temperature homeostasis is accurately regulated by complex feedback-driven neuronal mechanisms, which involve a multitude of thermoregulatory pathways. Thus, core temperature is constantly maintained within a narrow range. As one of the most effective regulatory systems skin temperature is dependent on skin blood flow. Skin blood flow in turn is highly dependent on sympathetic activity. Regional anaesthesia leads to blockade not only of somatosensory and motor nerve fibres but also of sympathetic fibres. As a consequence, vasoconstrictor tonic activity is abrogated and a vasodilation leads to an increase in skin blood flow and temperature. The aim of this review was to summarize the general physiology of thermoregulation and skin temperature as well as the alterations during regional anaesthesia. The main focus was the usefulness of measuring skin temperature as an indicator of regional anaesthesia success. According to the available literature, assessment of skin temperature can indeed serve to predict success of regional anaesthesia. Hence, it is important to realize that relevant and reliable temperature increase is only seen in the most distal body parts, ie fingers and toes. More proximally, temperature changes are frequently small and inconsistent, which means that assessment of block levels is not possible by temperature measurement. Furthermore, relevant skin temperature increases will only be observed in patients, which are initially vasoconstricted. In conclusion, measurement of skin temperature represents a reliable and feasible diagnostic tool to assess and predict the success or failure of regional anaesthesia procedures, especially in patients in which sensory testing is impossible.

Robot-assisted ramicotomy: evaluation in a swine model

BACKGROUND

To evaluate the feasibility of robot-assisted thoracoscopic T2-T5 ramicotomy.

METHODS

In 5 pigs, a robot-assisted thoracoscopic T2-T5 ramicotomy was performed, followed by T2-T5 sympathectomy 10 min later. Ramicotomy and sympathectomy times, and core (esophageal) and surface (left front foot) temperatures, were monitored and recorded.

RESULTS

The procedure was successfully completed in all 5 animals. In all cases, the sympathetic chain remained intact. No major hemorrhage occurred. The mean operating time for T2-T5 ramicotomy from incision until transsection of the last efferent ramus was 34 min (32-40). After completion of the ramicotomy, a total T2-T5 sympathectomy was performed, with a mean duration of 7 min (4-12). Mean core temperature before the operation was 37.6°C (36.7-38.0). Mean surface temperature before the operation was 34.2°C (33.3-35.5). Ten minutes after completion of the ramicotomy, temperatures stabilized. Mean postramicotomy core temperature was 37.4°C (36.3-38) and mean postramicotomy surface temperature was 35.4°C (33.9-37). Mean postsympathectomy temperatures were: core 37.3°C (36.1-38) and surface 35.8°C (33.8-37.1).

CONCLUSION

Robot-assisted thoracoscopic T2-T5 ramicotomy is feasible and effective in a porcine model.

Risks and benefits of thoracic epidural anaesthesia

Thoracic epidural anaesthesia (TEA) reduces cardiac and splanchnic sympathetic activity and thereby influences perioperative function of vital organ systems. A recent meta-analysis suggested that TEA decreased postoperative cardiac morbidity and mortality. TEA appears to ameliorate gut injury in major surgery as long as the systemic haemodynamic effects of TEA are adequately controlled. The functional benefit in fast-track and laparoscopic surgery needs to be clarified. Better pain control with TEA is established in a wide range of surgical procedures. In a setting of advanced surgical techniques, fast-track regimens and a low overall event rate, the number needed to treat to prevent one death by TEA is high. The risk of harm by TEA is even lower, and other methods used to control perioperative pain and stress response also carry specific risks. To optimize the risk-benefit balance of TEA, safe time intervals regarding the use of concomitant anticoagulants and consideration of reduced renal function impairing their elimination must be observed. Infection is a rare complication and is associated with better prognosis. Close monitoring and a predefined algorithm for the diagnosis and treatment of spinal compression or infection are crucial to ensure patient safety with TEA. The risk-benefit balance of analgesia by TEA is favourable and should foster clinical use.

Intestinal effects of thoracic epidural anesthesia

PURPOSE OF REVIEW

Thoracic epidural anesthesia (TEA) is most frequently used after major surgery. However, despite ongoing research, the influence of TEA on the intestinal perioperative pathophysiology is not fully understood.

RECENT FINDINGS

According to recent results, the splanchnic sympathetic activity is reduced during TEA both in animal models and in clinical TEA. The splanchnic sympathetic activity during high TEA is still unknown. Intestinal perfusion effects of TEA are still unclear as the technique and extent of TEA, hemodynamic alteration and size of measurement result in--seemingly--conflicting reports. Postoperative ileus after laparotomy is ameliorated by TEA. Recent findings suggest beneficial effects also after major laparoscopic procedures. Finally, the impact of TEA on the intestinal pathophysiology in critical illness is an area of growing clinical and scientific interest, although this knowledge is just at its beginning.

SUMMARY

Further research concerning the use of TEA in major laparoscopic procedures and its potential to improve or endanger anastomotic healing is warranted. The experimental studies of TEA in critical illness should be expanded.

Is there thermal benefit from preoperative warming in children?

AIM

We aimed to quantify the impact of a raised preoperative ambient temperature (T(ambient)) on core temperature (T(core)) after induction of anesthesia in children.

BACKGROUND

It has been suggested that prewarming of patients before anesthesia induction reduces postinduction drop in T(core). Neither the prewarming temperature nor its duration is established for adults or children. Nevertheless, it remains common practice to either warm the operating theatre and induction room or employ radiant heaters prior to induction of anesthesia, particularly for infants and neonates. We aimed to quantify the benefit, if any, of this warming practice.

METHODS

We conducted a prospective clinical study to assess T(core) behavior in children randomized to either raised or standard ambient temperature as a prewarming technique prior to induction and until the operation commenced. We have called this 'preoperative' warming. Well, children scheduled for elective surgery where presurgical anesthetic duration exceeded 20 min were randomized to a T(ambient) of either 26 or 21 degrees C. Esophageal temperature was monitored continuously until the operative procedure commenced.

RESULTS

There were 30 children in each group. Those in the warmed group (26 degrees C) had a statistically significant higher initial T(core) (0.4 degrees C warmer) and less drop in their T(core) (0.18 degrees C benefit at 20 min). Although younger/lighter/shorter individuals were more likely to drop their T(core), a warmer T(ambient) had only 0.1 degrees C thermal benefit irrespective of age.

CONCLUSIONS

There are statistically significant thermal advantages to preoperative environmental warming. This study provides data to assist the anesthetist in deciding when these are likely to be clinically relevant.

Long-term effects of thoracic sympathectomy on microcirculation in the hands of patients with primary Raynaud disease

OBJECTIVE

Videothoracoscopic sympathecomy is a widely used treatment modality in patients with severe Raynaud disease, but the reported late results are less than favorable. There have been no direct studies of the long-term effect of sympathectomy on microcirculation in the hands of these patients.

METHODS

In 25 patients with Raynaud disease treated with videothoracoscopic Th2-Th4 sympathectomy, we performed basal laser-Doppler flowmetry and measured the maximal refilling time after 1-minute occlusion measurements preoperatively and at 1 week, 6 months, and 1, 2, 3, and 5 years after the sympathectomy. The results were compared with the same measurements obtained in the group of 50 healthy individuals.

RESULTS

The patients' symptom severity was assessed by using the visual analogue scale. The basal capillary flow and the maximal refilling time improved after the sympathectomy to a level not different from that seen in the healthy population, and the effect was maintained during the 5-year follow-up period. The patients' symptom severity scores diminished to zero in the early postoperative period and increased to 28% of their initial value 5 years after the operation.

CONCLUSIONS

The videothoracoscopic Th2-Th4 sympathectomy produces excellent and long-lasting improvement of microcirculation function in patients with Raynaud disease. The mild return of symptoms might be due to factors other than the capillary blood flow alterations.

Laser Doppler scanning study of palmar skin perfusion for patients with hyperhidrosis before and after thoracic sympathectomy

BACKGROUND

Palmar hyperhidrosis is effectively treated by thoracic sympathectomy. Previous reports revealed that palmar skin temperature and perfusion increased on focal palmar regions after treatment. This study aimed to investigate the blood flow change over the whole palmar surface after the procedure.

METHODS

Thirty patients with severe palmar hyperhidrosis were included for study. Each participant received measurement of palmar skin perfusion by a laser Doppler image scanner 1 day before and 1 day after surgery. Concomitantly, palmar skin temperature was recorded by a contact thermometer probe. One patient underwent intraoperative recording of palmar skin perfusion.

RESULTS

Palmar skin perfusion and temperature increased significantly after thoracic sympathectomy. Intraoperative measurement performed for a patient showed a similar trend of increment of palmar skin blood flow.

CONCLUSIONS

The global skin perfusion of palms can be analyzed in real time by the laser Doppler image scanner. This technique could be useful for analysis of blood flow changes in other body surface regions after thoracic sympathectomy.

Hyperhidrosis: evolving therapies for a well-established phenomenon

The socially embarrassing disorder of excessive sweating, or hyperhidrosis, and its treatment options are gaining widespread attention. In order of frequency, palmar-plantar, palmar-axillary, Isolated axillary, and cranlofacial hyperhidrosis are distinct disorders of sudomotor regulation. A common link among these disorders is an excessive, nonthermoregulatory sweat response often to emotional stimuli in body regions influenced by the anterior cingulate cortex as opposed to the thermoregulatory sweat response regulated by the preoptic-anterior hypothalamus. Diagnosis of these mechanistically ambiguous disorders is primarily from patient history and physical examination, whereas results of laboratory studies performed with indicator powder reveal the distribution and severity of resting hyperhidrosis and document the integrity of thermoregulatory sweating. Treatment options lie on a continuum based on the severity of hyperhidrosis and the risks and benefits of therapy. In general, therapy begins with antiperspirants or anticholinergics. Iontophoresis is available for palmar-plantar and axillary hyperhidrosis. Botulinum toxin type A or local excision/curettage is effective for isolated axillary hyperhidrosis not responsive to topical application of aluminum chloride. Endoscopic thoracic sympathectomy may be used for severe cases of palmar-plantar and palmar-axillary hyperhidrosis. No sole therapy of choice has emerged for craniofacial sweating. The long-term sequelae of hyperhidrosis and its treatment also are discussed.