Near-infrared spectroscopy for assessing microcirculation during laparoscopic gynaecological surgery under combined spinal-general anaesthesia or general anaesthesia alone: a randomised controlled trial

Subclinical respiratory dysfunction and impaired ventilatory adaptation in degenerative cervical myelopathy

Degenerative cervical myelopathy (DCM) is a debilitating neurological condition characterized by chronic compression of the cervical spinal cord leading to impaired upper and lower limb function. Despite damage to areas of the cervical spinal cord that house the respiratory network, respiratory dysfunction is not a common symptom of DCM. However, DCM may be associated with respiratory dysfunction, and this can affect the ventilatory response to respiratory challenges during emergence from anesthesia, exercise, or pulmonary disease. Surgical spinal cord decompression, which is the primary treatment for DCM, leads to improved sensorimotor function in DCM; yet its impact on respiratory function is unknown. Here, using a clinically relevant model of DCM, we evaluate respiratory function during disease progression and assess adaptive ventilation to hypercapnic challenge before and after surgical intervention. We show that despite significant and progressive forelimb and locomotor deficits, there was no significant decline in eupneic ventilation from the early to late phases of spinal cord compression. Additionally, for the first time, we demonstrate that despite normal ventilation under resting conditions, DCM impairs acute adaptive ventilatory ability in response to hypercapnia. Remarkably, akin to DCM patients, surgical decompression treatment improved sensorimotor function in a subset of mice. In contrast, none of the mice that underwent surgical decompression recovered their ability to respond to hypercapnic ventilatory challenge. These findings underscore the impact of chronic spinal cord compression on respiratory function, highlighting the challenges associated with ventilatory response to respiratory challenges in individuals with DCM. This research highlights the impact of cervical spinal cord compression on respiratory dysfunction in DCM, as well as the persistence of adaptive ventilatory dysfunction after surgical spinal cord decompression. These results indicate the need for additional interventions to enhance recovery of respiratory function after surgery for DCM.

The Incidence of Acute Respiratory Infection Was Higher in the Older Adults with Lower Limb Fracture Who Receive Spinal Anesthesia Than Those Who Receive General Anesthesia

INTRODUCTION

Acute respiratory infection (ARI) can significantly reduce postoperative quality of life and impair the recovery of older adult patients with lower-limb fractures, and its relationship with methods of anesthesia remains inconclusive. Using data from the National Health Insurance Research Database (NHIRD) of Taiwan, this study examined the data of patients who received surgical management for lower-limb fractures and compared those who underwent general anesthesia (GA) with those who underwent regional anesthesia (RA) in terms of their incidence of acute upper and lower respiratory infection during the one-month postoperative period. The study also identified related risk factors.

MATERIAL AND METHODS

Approximately two million patients were randomly sampled from the NHIRD registry. We identified and enrolled patients with lower-limb fractures who were over 60 years old and underwent GA or RA during surgeries conducted between 2010 and 2017. We divided these patients into two groups for further analysis. The outcome of this study was the development of ARI during the one-month postoperative period.

RESULTS

In total, 45,032 patients (GA group, 19,580 patients; RA group, 25,452 patients) with a mean age of 75.0 ± 8.9 years were included in our study. The incidence of postoperative ARI within one month of surgery was 8.0% (1562 patients) in the GA group and 9.5% (2412 patients) in the RA group, revealing a significant difference. The significant risk factors for the incidence of ARI were the application of RA for surgery, older age, hypertension, liver disease, and chronic obstructive pulmonary disease (COPD). A subgroup analysis revealed that the RA method was associated with a significantly higher ARI incidence relative to the GA method among patients aged between 60 and 80 years, among male patients, among the patients with or without any comorbidity and among the patients without COPD.

CONCLUSION

The incidence of postoperative ARI within one month of surgery was higher among older patients with lower-limb fractures who received RA for surgery than among those who received GA for surgery. The other major risk factors for ARI were older age, hypertension, liver disease, and COPD. Therefore, we should focus on patients with a high risk of developing ARI, especially during the COVID-19 pandemic.

What is new in microcirculation and tissue oxygenation monitoring?

Ensuring and maintaining adequate tissue oxygenation at the microcirculatory level might be considered the holy grail of optimal hemodynamic patient management. However, in clinical practice we usually focus on macro-hemodynamic variables such as blood pressure, heart rate, and sometimes cardiac output. Other macro-hemodynamic variables like pulse pressure or stroke volume variation are additionally used as markers of fluid responsiveness. In recent years, an increasing number of technological devices assessing tissue oxygenation or microcirculatory blood flow have been developed and validated, and some of them have already been incorporated into clinical practice. In this review, we will summarize recent research findings on this topic as published in the last 2 years in the Journal of Clinical Monitoring and Computing (JCMC). While some techniques are already currently used as routine monitoring (e.g. cerebral oxygenation using near-infrared spectroscopy (NIRS)), others still have to find their way into clinical practice. Therefore, further research is needed, particularly regarding outcome measures and cost-effectiveness, since introducing new technology is always expensive and should be balanced by downstream savings. The JCMC is glad to provide a platform for such research.

Factors influencing lower respiratory tract infection in older patients after general anesthesia

Objective

Pulmonary complication is common in older patients after surgery. We analyzed risk factors of lower respiratory tract infection after general anesthesia among older patients.

Methods

In this retrospective investigation, we included older patients who underwent surgery with general anesthesia. Logistic regression analyses were performed to determine risk factors of lower respiratory tract infection.

Results

A total 418 postoperative patients with general anesthesia were included; the incidence of lower respiratory tract infection was 9.33%. Ten cases were caused by gram-positive bacteria, 26 cases by gram-negative bacteria, and 2 cases by fungus. We found significant differences in age, smoking, diabetes, oral/nasal tracheal intubation, and surgery duration. Logistic regression analysis indicated that age ≥70 years (odds ratio [OR] 2.028, 95% confidence interval [CI] 1.115–3.646), smoking (OR 2.314, 95% CI 1.073–4.229), diabetes (OR 2.185, 95% CI 1.166–4.435), nasotracheal intubation (OR 3.528, 95% CI 1.104–5.074), and duration of surgery ≥180 minutes (OR 1.334, 95% CI 1.015–1.923) were independent risk factors of lower respiratory tract infections.

Conclusions

Older patients undergoing general anesthesia after tracheal intubation have a high risk of lower respiratory tract infections. Clinical interventions should be provided to prevent pulmonary infections in patients with relevant risk factors.

The Effect of Transoral Endoscopic Thyroidectomy Vestibular Approach on Regional Cerebral Oxygen Saturation: A Prospective Observational Study

BACKGROUND

Decreased regional cerebral oxygen saturation (rSO2) is associated with neurological events. We aimed to investigate the effects of carbon dioxide (CO2) insufflation applied to the neck during transoral endoscopic thyroidectomy vestibular approach (TOETVA) surgery on the rSO2.

MATERIALS AND METHODS

Patients scheduled for TOETVA and open thyroidectomy (OT) were enrolled between October 2019 and November 2020. Alongside hemodynamic parameters, the rSO2 values of the patients were recorded at 5 different times. These were; before anesthesia induction (T0), 10 minutes after anesthesia induction (T1), 5 minutes after the patient was placed in the operation position (T2), 10 minutes after the CO2 insufflation in the TOETVA group, 10 minutes after the platysma incision in the OT group (T3), 10 minutes after the CO2 desufflation in the TOETVA group, 10 minutes after platysma closure in the OT group (T4), at the end of the surgery (T5).

RESULTS

A total of 40 patients, 20 in each group, were included in the study. The surgery duration was 113±26.9 minutes in the OT group, while it was 274.1±78.1 minutes in the TOETVA group (P=0.000). The EtCO2 values during the T3 time interval; group OT 31±2.2, group TOETVA 33.9±2.1 (P=0.000). The rSO2 values of the patients were similar, except for the T3 time interval. While the right rSO2 value we obtained during the T3 time interval in the TOETVA and OT groups were 66.9±9.1 and 73.9±7.8 (P=0.013), the left rSO2 value in the TOETVA and OT groups were 66.3±9.9 and 74.8±6.8 (P=0.003), respectively.

CONCLUSIONS

As long as the patients stay within the limits of normocapnia, the CO2 insufflation applied during TOETVA surgery has no negative effects on rSO2.

Changes in the microvascular reactivity during spinal anesthesia

PURPOSE

Anesthesia alters microcirculation and tissue oxygen saturation (StO₂). We sought to examine changes in StO₂ using near-infrared spectroscopy and a vascular occlusion test (VOT) during spinal anesthesia.

METHODS

This prospective observational study was included 51 patients without comorbidities who underwent elective surgery under spinal anesthesia. We measured the StO₂ in the lower extremity during VOT before and after intrathecal injection.

RESULTS

The baseline, minimum, and maximum StO₂ values during VOT significantly increased after intrathecal injection (baseline StO₂ from 68.6 ± 7.3% to 77.1 ± 10.1%, minimum StO₂ from 39.7 ± 14.9% to 48.8 ± 17.6%, and maximum StO₂ from 74.2 ± 7.5% to 80.2 ± 10.0%, all P < 0.0001). The occlusion slope and ischemic stimulus did not significantly change after intrathecal injection. The reperfusion slope was 1.38 ± 0.69%/sec before intrathecal injection and significantly decreased to 1.15 ± 0.61%/sec after intrathecal injection (P = 0.0001).

CONCLUSIONS

Our results showed that despite an increased perfusion, reperfusion rate was significantly decreased by spinal anesthesia. Further studies are required to confirm how these contradictory results (improving oxygenation while reducing microvascular reactivity) actually affect the clinical impact of spinal anesthesia on microvascular function.

A prospective randomized controlled study of combined spinal-general anesthesia vs. general anesthesia for laparoscopic gynecological surgery: Opioid sparing properties

STUDY OBJECTIVE

We aimed to determine the magnitude of peri-operative opioid sparing effect when general anesthesia is combined with spinal analgesia for laparoscopic gynecological surgery.

DESIGN

A prospective randomized controlled study; a three-group trial with two comparisons (each intervention group to control).

SETTING

Operating room and postoperative recovery area.

PATIENTS

Patients aged between 18 and 65 years with American Society of Anesthesiologists physical status 1 or 2 who were scheduled for inpatient elective laparoscopic gynecological surgery with expected pneumoperitoneum duration of at least 20 min. Of 102 randomized patients, 99 completed the study.

INTERVENTIONS

Patients were randomized to general anesthesia alone (control group) or combined with very-low-dose (levobupivacaine 3.75 mg; sufentanil 2.5 μg) or low-dose (levobupivacaine 7.5 mg; sufentanil 2.5 μg) spinal analgesia.

MEASUREMENTS

Primary endpoints were perioperative opioid consumption and pain scores (11-point numeric rating scale) at 30 min, 1 h, 2 h, 4 h and 24 h post-surgery. Secondary endpoints were patient satisfaction with anesthetic care and participation in research, sevoflurane consumption and adverse effects.

MAIN RESULTS

Intra-operative sufentanil (median [95% CI]) consumption was 16.1 (10.5-22.6) μg/h in the control group versus 4.7 (3.2-9.2) μg/h in the very-low-dose and versus 2.9 (0.0-4.0) μg/h in the low-dose spinal analgesia groups (p < 0.001, for both comparisons). Median (95% CI) piritramide consumption at 24 h post-surgery was 7.5 (3-8) mg in the control group versus 5 (0-7.5) mg in the very-low dose spinal analgesia group (p = 0.182) and versus 2 (0-2.5) mg in the low-dose spinal analgesia group (p = 0.001). Postoperative pain scores were consistently <3 only in the low dose spinal analgesia group. Patient satisfaction with anesthetic care and participation in research was very high in all groups.

CONCLUSIONS

Low-dose spinal analgesia in combination with general anesthesia reduces peri-operative opioid consumption in laparoscopic gynecological surgery in immediate postoperative period.