Association between heated tobacco product use and airway obstruction: a single-centre observational study, Japan.

BACKGROUND: While heated tobacco products (HTPs) may affect pulmonary function, the evidence supporting the utility of screening for HTP use in clinical settings is insufficient. We examined the association between HTP use and airway obstruction after switching from cigarettes. METHOD: The study subjects were patients aged ≥20 years undergoing surgery from December 2021 to September 2022 who completed spirometry and reported tobacco (cigarette and HTP) use status during the preoperative assessment. Airway obstruction was defined as forced expiratory volume in 1 s to forced vital capacity ratio below the lower limit of normal. Current tobacco use was defined as past-30-day use. Multivariable Poisson regression analysis was performed to examine the associations between HTP use and airway obstruction by adjusting for demographic characteristics, lifetime cigarette smoking (pack-year) and duration of smoking cessation. RESULTS: Overall (N=2850, 55.4% women, mean age 62.4), 4.6% and 10.7% reported current HTP use and cigarette smoking, respectively. 16.8% had airway obstruction. Airway obstruction was more common among current HTP-only users (adjusted prevalence ratio (APR)=2.32), current cigarette-only smokers (APR=2.57) and current dual users (APR=2.82) than never-tobacco users. Among current tobacco users (N=398), the prevalence of airway obstruction was not significantly different between HTP-only users and cigarette-only smokers. Among former cigarette smokers (>30-day cigarette quitters) (N=1077), current HTP users had 1.42 times the increased prevalence of airway obstruction than never-HTP users after adjusting for cigarette pack-year; a stronger association was observed when the analysis was restricted to ≥5-year cigarette quitters (N=772) (APR=1.96, vs never HTP users). CONCLUSION: Current HTP use was associated with airway obstruction among patients with cancer who had completely switched from cigarettes even after quitting smoking for a long period. Patients should be routinely screened for HTP use and advised to quit any tobacco.

Successful weaning of a patient with severe COVID-19 pneumonia under prolonged midazolam sedation using morphine.

The coronavirus disease 2019 (COVID-19) pandemic continues to spread around the world. In April 2021, Japan experienced a fourth wave of COVID-19 infections, which led to the breakdown of the medical system. Osaka, Japan, was particularly affected, with many severe cases and the highest number of COVID-19-associated deaths in Japan. Herein, we present a patient with severe COVID-19 infection who received prolonged midazolam (MDZ) treatment since propofol was not available due to shortage of medical resources. Moreover, the duration of mechanical ventilation was extended due to the development of a pneumothorax. When MDZ tapering was initiated, tachypnea was observed, which resulted failure in ventilator weaning. However, the use of continuous morphine infusion led a successful weaning off the ventilator. We suggest that the administration of morphine may allow for a smoother weaning process for some patients with severe COVID-19 infection.

New Magnetic Resonance Imaging Features Predictive for Post-Treatment Ambulatory Function: Imaging Analysis of Metastatic Spinal Cord Compression.

STUDY DESIGN: This is a retrospective, single-institute, radiographical study. OBJECTIVE: The study aimed to determine the correlation of magnetic resonance imaging (MRI) findings observed in metastatic spinal cord compression (MSCC) with post-treatment ambulatory status. SUMMARY OF BACKGROUND DATA: Previous studies have reported various predictors of ambulatory outcome in patients with MSCC, but the relationship between the MRI features and post-treatment ambulatory function remains to be elucidated. METHODS: Fifty-six hospitalized patients with MSCC and risk of MSCC were examined using MRI before therapeutic intervention. Circumferential ratio of cord compression (CRCC), clock position of compression, cross-sectional area (CSA), and change in signal intensity of the spinal cord were recorded. Each imaging feature was analyzed statistically regarding unassisted ambulatory status at the time of hospital discharge as the endpoint. RESULTS: CRCC showed a prognostic value for post-treatment ambulatory function. More than half of CRCC predicted poor functional prognosis with statistical significance. However, the site of cord compression expressed by clock position on axial plane showed no relationship with functional prognosis. CSA of the spinal cord was enlarged in 23% of patients at the level of MSCC, which indicated that cord compression could also be formed by a relative relationship between cord swelling and surrounding mass effect. The said patients showed a better functional outcome. High intensity of the spinal cord on T2-weighted sagittal image was not useful because of lack of inter-rater reliability. CONCLUSION: CRCC on axial T2 image can guide clinicians to identify cancer patients at risk of paraplegia because of MSCC. More than half of CRCC entails urgent treatment despite preserved ambulatory function. Furthermore, some cases of MSCC accompany increased cord CSA. The measurement is also a useful guide to balance the risk and benefit of systemic steroid therapy. MRI is the key imaging modality in the risk assessment of MSCC. LEVEL OF EVIDENCE: 4.

[A case of previously undiagnosed methemoglobinemia exhibiting sustained low SpO2 value at the induction of general anesthesia].

A 70-year-old woman was scheduled to undergo surgery for removal of thyroid tumor under general anesthesia. A routine preoperative evaluation confirmed that the patient was stable with no signs of cyanosis and dyspnea. However, during pre-oxygenation as well as mechanical ventilation with 100% oxygen, she showed sustained low SpO2 values (i.e., 91%). Arterial blood gas analysis at FIO2 of 1.0 showed an oxygen partial pressure (PaO2) of 297 mmHg. Unexpectedly, the analysis revealed methemoglobinemia (MetHb concentration: 15%) causing a discrepancy between the low SpO2 and normal PaO2 values in this patient. Methemoglobinemia is an uncommon cause of cyanosis; however, anesthesiologists should be aware that some drugs used during perioperative period (e.g., local anesthetics) can cause methemoglobinemia. While our case was a mild one and the patient recovered with no complications, methemoglobinemia levels above 30% could cause tissue hypoxemia and, thereby, requiring a treatment with methylene blue or ascorbic acid.

Thrombomodulin: a bifunctional modulator of inflammation and coagulation in sepsis.

Deregulated interplay between inflammation and coagulation plays a pivotal role in the pathogenesis of sepsis. Therapeutic approaches that simultaneously target both inflammation and coagulation hold great promise for the treatment of sepsis. Thrombomodulin is an endogenous anticoagulant protein that, in cooperation with protein C and thrombin-activatable fibrinolysis inhibitor, serves to maintain the endothelial microenvironment in an anti-inflammatory and anticoagulant state. A recombinant soluble form of thrombomodulin has been approved to treat patients suffering from disseminated intravascular coagulation (DIC) and has thus far shown greater therapeutic potential than heparin. A phase II clinical trial is currently underway in the USA to study the efficacy of thrombomodulin for the treatment of sepsis with DIC complications. This paper focuses on the critical roles that thrombomodulin plays at the intersection of inflammation and coagulation and proposes the possible existence of interactions with integrins via protein C. Finally, we provide a rationale for the clinical application of thrombomodulin for alleviating sepsis.

Oral gastric tube-guided insertion of the ProSeal™ laryngeal mask is an easy and noninvasive method for less experienced users.

PURPOSE: The ProSeal™ laryngeal mask airway (PLMA) can be more difficult to insert than the classic laryngeal mask, especially in patients who have a thin palate with a steep oropharyngeal curve. Here, an oral gastric (OG) tube-guided technique is considered as a method that makes it easier to successfully insert a PLMA. METHODS: Sixty patients who were scheduled to undergo general anesthesia without neuromuscular blocking were randomly allocated into two groups: 30 patients with PLMA inserted by the standard digital technique, and 30 with the PLMA inserted by an OG tube-guided technique. Most PLMA insertions were performed by less experienced users. The success rate at the first attempt, the time taken to insert the PLMA, the difficulty of the procedure, and the incidence of oropharyngeal trauma and postoperative sore throat were compared between the two groups. RESULTS: PLMA insertion was successfully achieved at the first attempt using the OG tube-guided technique in all 30 patients. The OG tube-guided insertion required fewer attempts (P = 0.04) and led to a less difficult insertion procedure (P = 0.02) than the standard digital insertion. Effective ventilation during anesthesia was achieved in all patients, with a lower mean cuff pressure in the OG tube-guided technique group (P = 0.02). The frequency of blood sticking to the PLMA tube (P < 0.001) and the incidence of postoperative sore throat (P = 0.003) were lower in the OG tube-guided group than the standard digital technique group. CONCLUSIONS: OG tube-guided PLMA insertion is easier for less experienced users, trainees, and experts as well as less invasive for patients than the standard digital insertion.

Astroglial integrins in the development and regulation of neurovascular units.

In the neurovascular units of the central nervous system, astrocytes form extensive networks that physically and functionally connect the neuronal synapses and the cerebral vascular vessels. This astrocytic network is thought to be critically important for coupling neuronal signaling activity and energy demand with cerebral vascular tone and blood flow. To establish and maintain this elaborate network, astrocytes must precisely calibrate their perisynaptic and perivascular processes in order to sense and regulate neuronal and vascular activities, respectively. Integrins, a prominent family of cell-adhesion molecules that support astrocytic migration in the brain during developmental and normal adult stages, have been implicated in regulating the integrity of the blood brain barrier and the tripartite synapse to facilitate the formation of a functionally integrated neurovascular unit. This paper describes the significant roles that integrins and connexins play not only in regulating astrocyte migration during the developmental and adult stages of the neurovascular unit, but also in general health and in such diseases as hepatic encephalopathy.

[Pre-operative smoking cessation does not always reduce the incidence of surgical site infection after gastrointestinal surgery].

BACKGROUND: Centers for Disease Control (CDC) recommend pre-operative smoking cessation to reduce the risk of surgical site infection (SSI). However, whether pre-operative smoking cessation reduces the incidence of SSI for gastrointestinal surgery is unclear. We investigated whether pre-operative smoking cessation reduces the incidence of SSI among patients undergoing gastrointestinal surgery. METHODS: The study subjects were 512 consecutive patients undergoing gastrointestinal surgery at Osaka Medical Center for Cancer and Cardiovascular Diseases. SSI occurrence was determined by the hospital SSI surveillance team. Pre-operative smoking status was obtained by interview, and the patients were divided into four groups. Information on age, sex, operation time, operational organ, American Society of Anesthesiologists physical status (ASA-PS), elective or emergency surgery, co-existing procedures, use of scopes, ileo-colostomy, properties of drain tube, use of floss, and wound contamination was obtained from the medical records. The relationship between smoking status and incidence of SSI, and risk factors associated with the incidence of SSI were investigated. RESULTS: SSI occurred in 83 patients. Pre-operative smoking status had no relation with the incidence of SSI. Operation time, gallbladder and pancreatic surgery, colon surgery, emergency surgery, co-existing procedures, ilea-colostomy, closed drain, usage of floss, and wound contamination were related significantly with SSI. CONCLUSIONS: Pre-operative smoking cessation does not reduce the incidence of SSI. However, since continuation of smoking has no benefits for the safety of surgery, anesthesiologists must advice patients to quit smoking before surgery.

[Internal jugular vein cannulation guided by pulsation].

BACKGROUND: We are accustomed to right internal jugular vein (IJV) cannulation guided by pulsation for 20 years or more. This study was conducted to evaluate whether this method is a safe and certain method. METHODS: After obtaining informed consent, 100 elective surgical patients requiring central venous catheterization during perioperative period were randomly assigned to either the pulsation group in which IJV pulsation was used for a landmark of puncture or the US group in which IJV was recognized with ultrasonography before puncture. RESULTS: Pulsation was observed in 98 patients. Successful rate of first attempt with a 23 G seeking needle was 85.7% in the pulsation group and 86% in the US group. IJV was successfully cannulated at 1 pass in the entire pulsation group and 92% in the US group. The frequency of puncture with cannula was significantly lower in the pulsation group than that of the US group. Arterial puncture with the seeking needle was recorded in 3 patients in the US group. Successful rate of first attempt in this study was comparable to other studies using ultrasonographic guidance. CONCLUSIONS: Internal jugular vein cannulation by pulsation method is a safe and certain method.

[Remifentanil provides fast recovery and hemodynamic stability in laryngomicrosurgery anesthesia].

BACKGROUND: Stressful procedures such as intratracheal intubation and direct laryngoscopy in very short operations make anesthetic management for laryngomicrosurgery difficult. This study was conducted to evaluate which anesthetic agent, remifentanil or fentanyl, is suitable in anesthesia for laryngomicrosurgery. METHODS: After obtaining informed consent prior to the study, 18 patients undergoing elective laryngomicrosurgery were randomly allocated to one of two groups to receive remifentanil (R group) or fentanyl (F group). Patients with ages above 76 years and moderate abnormalities in cardiovascular system or respiratory system were excluded. RESULTS: Average infusion rate of remifentanil was 0.24 +/- 0.02 microg x kg(-1) x min(-1) and total infused dose of fentanyl was 0.27 +/- 0.05 mg. Average bispectral index values in both groups were comparable. Cases needing sevoflurane inhalation to control blood pressure were significantly more in F group than in R group. Heart rate was significantly lower in R group than in F group. Duration from the end of operation to responses to verbal commands and extubation was significantly shorter in R group than in F group. CONCLUSIONS: Remifentanil provided faster recovery and hemodynamic stability. Therefore, remifentanil seems to be more suitable than fentanyl in anesthesia for laryngomicrosurgery.

[Prophylactic strategies for perioperative pulmonary thromboembolism in cancer patients].

BACKGROUND: Our previous reports showed that elastic stockings (ES) combined with intermittent pneumatic compression (IPC) significantly decrease the incidence of perioperative pulmonary thromboembolism (PTE). This study was conducted to investigate whether ES with IPC is useful to prevent PTE in cancer patients. METHODS: No prophylactic strategies were employed from January 1998 to December 1999 (4511 cases). ES combined with ICP apparatuses was employed from May 2000 to April 2008 (20,383 cases). Details of the methods were described in our previous reports. RESULTS: Age, anesthesia duration and operation duration increased statistically without clinical significances after the induction of prophylactic strategies. About 90 per cent of surgical patients had malignant disease. Seven patients developed PTE without any interventions and 5 patients with treatments. The incidence of PTE decreased significantly from 15.51 persons/10,000 cases to 2.45 persons/10,000 cases. Cardiac arrest occurred in two untreated patients but in no treated patient. Intervention also significantly decreased the incidence of cardiac arrest. CONCLUSIONS: The combination of ES and ICP seems to be useful to decrease the incidence and severity of perioperative PTE in cancer patients in Japan.

Dopamine D2 receptor Taq IA polymorphism is associated with postoperative nausea and vomiting.

PURPOSE: The dopamine D2 receptor (DRD2) is considered to be involved in the development of postoperative nausea and vomiting (PONV). Our aim was to examine the relationship between DRD2 Taq IA polymorphism and the occurrence of PONV. METHODS: We enrolled 1070 patients who were scheduled to undergo elective surgery under general anesthesia. Patients who vomited or required rescue antiemetics for severe nausea at two time points (within 6 and within 24 h after surgery) were defined as having early and total PONV, respectively. A polymerase chain reaction with confronting two-pair primers (PCR-CTPP) technique was adopted for DRD2 genotyping allele (A1A1, A1A2, or A2A2). The relationship between DRD2 Taq IA polymorphism and the occurrence of PONV was examined by multivariate logistic regression analysis. RESULTS: The incidences of early PONV were 9.0%, 9.3%, and 14.4% in patients with the A1A1, A1A2, and A2A2 alleles, respectively. Sex, nature of the disease, smoking status, type of surgical department, duration of anesthesia, and the DRD2 Taq IA polymorphism were related to the emergence of early PONV. On multivariate analysis, the relative risk associated with the A2A2 allele in comparison with the A1A1 or A1A2 allele was 1.58 (95% confidence interval [CI], 1.05-2.37) for early PONV. The incidences of total PONV were 12.5%, 13.6%, and 17.2% in patients with the A1A1, A1A2, and A2A2 alleles, respectively. Sex, smoking status, type of surgical department, and duration of anesthesia were related to the emergence of total PONV. On multivariate analysis, the relative risk associated with the A2A2 allele in comparison with the A1A1 or A1A2 allele was 1.27 (95% CI, 0.88-1.84) for total PONV. CONCLUSION: The DRD2 Taq IA polymorphism affected the occurrence of early PONV. Analysis of patients' genetic backgrounds may improve risk-stratification for PONV.

[Wound healing in reconstructive head and neck surgery].

BACKGROUND: Smoking cessation and shorter operative duration are known as factors to improve wound healing in reconstructive head and neck surgery. We investigated the other factors associated with wound healing. METHODS: Informations on age, sex, body mass index, smoking status, serum albumin level, diabetes mellitus, chronic obstructive pulmonary diseases, preoperative steroid therapy, preoperative chemotherapy, preoperative radiation therapy, preoperative starvation care, American Society of Anesthesiologists physical status (ASA-PS), intraoperative administration of prostaglandin E1, operative duration, and type of flap were obtained from the medical records of 370 patients. Requirements of postoperative intervention were also recorded. Factors associated with wound healing were estimated by multivariate analysis. RESULTS: Compared with smokers, 22 to 42 day smoking quitters, over 43 day smoking quitters, and non-smokers had lower incidence of wound complications; odds ratio; 95% confidence intervals (CI) were 0.20; 0.06-0.68, 0.19; 0.07-0.51, and 0.15; 0.05-0.45, respectively. Other factors and odds ratios (95% CI) associated with wound complications were preoperative chemotherapy; 3.02 (1.09-8.41), preoperative starvation; 0.23 (0.06-0.84), every one minute of operation duration; 1.01 (1.00-1.01). CONCLUSIONS: Preoperative smoking cessation, preoperative chemotherapy, preoperative starvation care, and operation duration were significantly associated with wound healings.

[Prophylactic strategies for perioperative pulmonary embolism: the second report; reevaluation of usefulness of combination of elastic stockings and intermittent pneumatic compression].

BACKGROUND: The incidence of perioperative pulmonary thromboembolism (PTE) has increased in Japan. As the mortality rate of PE is very high, its prophylaxis is important. METHODS: From January 1998 to December 1999 no prophylactic strategies were employed. From May 2000 to December 2004, elastic stockings (ES) for prevention of perioperative deep vein thrombosis were worn from the morning of the operation until the beginning of ambulation. Intermittent pneumatic compression (IPC) apparatuses were used in combination with ES right after the induction of anesthesia until leaving ICU. Sixty percent of patients stayed in ICU until the next morning after the operation and the other patients for a few hours after the end of surgery. RESULTS: We managed 4,511 patients without any preventing method and 11,688 patients with the combination of ES and IPC. Seven patients developed PTE without any prophylaxis and one with preventative methods. The incidence of PTE was significantly decreased from 15.51 persons/10,000 cases to 0.86 person/10,000 cases. Symptomatic deep vein thrombosis occurred in 3 cases in spite of preventative methods. CONCLUSIONS: Our preventive strategies with the combination of ES and IPC seem to be useful to decrease the incidence and severity of perioperative PTE.

[Prophylaxis of perioperative pulmonary thromboembolism in a patient with anti-phospholipid antigen syndrome].

A 68-year-old woman with anti-phospholipid antigen syndrome (APS) was proposed to undergo partial pulmonary resection for lung cancer. She suffered from mild cerebellar ataxia. Exercised 201Tl myocardial scintigraphy was performed due to abnormal Q wave in preoperative electrocardiography and showed old myocardial infarction in inferior-to-posterior area without myocardial ischemia. Cardiac function was marginally decreased in cardiac echographic evaluation. Arterial thrombosis by APS might cause cerebellar ataxia and myocardial infarction. Low molecular weight heparin (LMWH) was continuously infused from 1 hour prior to arrival in an operation room. Elastic stockings (ES) were worn from the morning of the operation in combination with the use of intermittent pneumatic compression apparatus (IPC). Significant bleeding was not observed perioperatively. Hypothermia was avoided by forced-air-warming therapy. She was transferred to ICU after the end of the operation. She was returned to her ward without IPC on the first postoperative day. Warfarin was given with the beginning of ambulation on the second postoperative day to keep PT-INR about 2. On the third postoperative day LMWH was discontinued and ES were taken off. The postoperative course was uneventful.

[Short-term bed rest as a cause of deep vein thrombosis in a patient with a huge abdominal tumor].

A 43-year-old female with a huge myoma uteri was scheduled for a simple total hysterectomy. However, there was massive penetration of the tumor into the retroperitoneum, and her first operation failed because we had no advance information on its posterior aspect. Angiography was done to obtain this information. She rested on bed until the day after the first operation and angiography. MRI, performed again due to early growing tumor, revealed deep vein thrombi in the left iliac vein to the left femoral vein which the last MRI had not shown. Therefore, just before the second operation a temporary vena-cava filter was inserted, to prevent acute pulmonary thromboembolism. The operation was performed without incident. The filter captured some thrombi, and these were resolved by urokinase postoperatively. No symptomatic pulmonary thromboembolism was recognized during the perioperative period. The postoperative course was uneventful.

[A case of silent rupture of a cerebral arteriovenous malformation during laparotomy].

A 52-year-old female, scheduled for rectal cancer resection, had no history of central nervous system abnormality. Anesthesia was maintained with general anesthesia combined with epidural anesthesia. Her only hemodynamic change was a rise in arterial pressure to 140 mmHg just after the start of the operation. However, postoperatively she failed to be aroused and she exhibited a positive Babinski's sign, anisocoria, an absent light reflex and paresis of the left lower extremity. Cerebral vascular accident was suspected and a CT scan revealed a cerebral hematoma which was immediately removed surgically. Upon exploration, abnormal vessels were recognized and we diagnosed an acute rupture of arteriovenous malformation. She fully recovered consciousness immediately after the operation. Her postoperative course was uneventful, except for a residual paresis of the left lower extremity.

[Prophylactic strategies for perioperative pulmonary embolism].

BACKGROUND: Incidence of perioperative pulmonary embolism (PE) has increased in Japan probably due to the modernized life style. As the mortality rate of PE is very high, its prophylaxis is important. Therefore, prophylactic strategies for PE were instituted in the entire hospital. METHODS: Elastic stockings (ES) for preventing perioperative deep vein thrombosis in lower extremities were worn from the morning of the operation until the beginning of ambulation. Intermittent pneumatic compression (IPC) apparatuses were used in combination with ES. IPC apparatus was employed right after induction of anesthesia until leaving postanesthetic care unit (PACU). Seventy percent of patients stayed in PACU until the morning after the operation and the other patients for a few hours after the end of surgery. RESULTS: We managed 4,200 patients with this method. We experienced one symptomatic deep vein thrombosis but not severe or moderately severe PE. However, it is difficult to evaluate the incidence of mild PE because it is usual that symptom such as chest discomfort is thought as an indefinite complaint and its cause is not investigated further. CONCLUSIONS: Our preventive strategies seem to be useful to decrease the incidence and severity of perioperative PE.

[Occupational exposure of operating room staff to anesthetic gases during inhaled induction--a comparison with intravenous anesthesia induction].

BACKGROUND: The risk of occupational exposure to waste anesthetic gases still remains during inhaled induction. In this study we investigated how much we were occupationally exposed to anesthetic gases during induction period. METHODS: Twenty-six adult patients were induced with sevoflurane 5% using a face mask for three minutes and maintained with sevoflurane 1% after end-tracheal intubations (IH-Group). Twenty-two adult patients were induced with intravenous anesthetics and maintained with sevoflurane 1% after end-tracheal intubations(IV-Group). The concentration of sevoflurane was measured by Multi-gas Monitor 1302 (Bruel & Kjaer: Denmark) every 70 seconds. Sample gas was suctioned from breathing zone of anesthesiologists. All of our operating rooms are equipped with waste gas scavenging system. RESULTS: The peak concentration of sevoflurane is significantly higher in IH-Group (15.91 +/- 22.64 ppm) compared with IV-group (0.36 +/- 0.25 ppm). The period when sevoflurane concentration exceeded 0.5 ppm is significantly longer IH-Group (18.55 +/- 10.51 min.) compared to IV-Group (1.92 +/- 4.56 min.). CONCLUSION: The induction with intravenous anesthetics is a better method in order to reduce occupational exposure of anesthesiologists to anesthetic gases.

[Intensive care management of acute pulmonary thromboembolism].

Three patients with acute pulmonary thromboembolism, who had fallen into cardiopulmonary arrest or severe respiratory failure, were treated and saved in our intensive care unit. Two patients were resuscitated with percutaneous cardiopulmonary support device. Two patients underwent surgical embolectomy and we carefully applied positive pressure ventilation to prevent postoperative reperfusion pulmonary edema. Early diagnosis and treatment are essential for saving critically ill patients with acute pulmonary embolism. However, cardiopulmonary resuscitation is often difficult and unsuccessful. Therefore prophylaxis is strongly recommended especially in patients with known risk factors of venous thrombosis. Since reperfusion pulmonary edema is a serious complication after surgical pulmonary embolectomy, careful postoperative respiratory care is needed.