Hiroshi Hoshijima

Background: The relationship between postoperative nausea and vomiting (PONV) and postoperative pain (POP) has not yet been fully clarified. This investigation aimed to evaluate the association between postoperative nausea severity and the intensity of POP following minor oral and maxillofacial surgery (OMS) under general anesthesia. Methods: This retrospective cohort study reviewed data from patients aged 16 to 70 years who received general anesthesia with nasal intubation for minor OMS at our institution from January 2021 to August 2022; patients with pre-existing conditions influencing POP or PONV were excluded from the analysis. Predictor variables included nausea scores assessed with a 100 mm visual analog scale (VAS), with a secondary sub-analysis excluding asymptomatic patients. The primary and secondary outcomes were VAS-rated POP levels at early (2 h) and late and delayed (6 h and 24 h) time points post-surgery, respectively. Covariates encompassing patient demographics, anesthetic details, and surgical factors were adjusted for, with statistical significance defined as p < 0.05. Results: Out of the 160 patients analyzed, the PONV incidence rates were 20.0% (n = 32) at 0–2 h, 4.4% (n = 7) at 2–6 h, and 0% (n = 0) at 6–24 h. The results from the adjusted multivariate model analysis show that, in this cohort of 160 patients—regardless of the presence or absence of PONV—higher nausea severity was not significantly associated with a reduction in POP intensity at the 2 h mark in the primary analysis. However, in an exploratory subgroup analysis, in the 32 patients who experienced PONV at the 2 h time point, higher nausea severity was significantly associated with lower POP levels [regression coefficient = −0.45, 95% confidence interval = −0.77 to −0.14, p = 0.006]. Conclusions: These results demonstrate an inverse statistical association between nausea severity and POP intensity at 2 h within a small subgroup of 32 patients with PONV. However, these findings do not establish a causal relationship.

Postoperative nausea and vomiting (PONV) is a frequent and serious complication after surgery. PONV also reduces patient satisfaction with surgery under spinal anesthesia and increases medical costs due to prolonged hospitalization. The purpose of this study is to apply artificial intelligence (AI) machine learning analysis to identify risk factors for PONV in patients undergoing surgery with spinal anesthesia. This retrospective study used artificial intelligence to analyze data of adult patients (aged ≥20 years) who underwent surgery under spinal anesthesia at Tohoku University Hospital from January 1, 2010 to December 31, 2022. To evaluate PONV, patients who experienced nausea and/or vomiting or used antiemetics within 24 hours after surgery were extracted from postoperative medical records. The selected data were analyzed after propensity score matching with patients who did not experience PONV. We created an ensemble model for predicting the probability of PONV using five machine learning algorithms: random forest, gradient boosting machine, k-nearest neighbor, multilayer perceptron, and decision tree. Data were available for 4,574 patients. We performed propensity score matching and selected 538 patients for analysis (269 in the PONV group and 269 in the non-PONV group). The use of postoperative fentanyl was identified as the strongest contributor to PONV, followed by duration of surgery, body mass index (BMI), total urine output, and duration of anesthesia. The identified risk factors were female sex, BMI < 25 kg/m ² , and duration of surgery (< 60 min), duration of anesthesia (< 100 min), cesarean section, use of postoperative fentanyl, administration of fentanyl/ morphine into the spinal arachnoid, and puncture level of epidural anesthesia (Th7–12) were identified as anesthesia/surgery-related risk factors. We used machine learning AI to evaluate risk factors for PONV after spinal anesthesia. We identified several patient-related and anesthesia/surgery-related risk factors for PONV. The AI analysis used in this study was accurate enough to identify risk factors for PONV during spinal anesthesia and may provide sufficient evidence for predicting PONV.

Background and Objectives: Phantom limb pain (PLP) frequently occurs after lower limb amputation (LLA). However, a consensus has not been reached regarding its incidence, particularly in nontraumatic amputations, because reported estimates vary according to case mix, follow-up duration, and outcome definitions. Data from Japan remain limited. Methods: After approval by the Institutional Review Board, the electronic medical records of patients who underwent above-knee amputation (AKA) or below-knee amputation (BKA) at Saitama Medical University Hospital between 1 January 2012 and 31 December 2024 were retrospectively reviewed. The primary outcome was the incidence of clinically documented PLP during hospitalization, typically within approximately 1–2 months after amputation. PLP was defined as a painful sensation in the amputated limb documented in the medical record and diagnosed by surgeons or anesthesiologists. Postamputation pain due to symptomatic neuroma was not classified as PLP. Patients with only nonpainful phantom limb sensations were not considered to have the primary outcome. Patients aged 18 years or older who required nontraumatic AKA or BKA were included. Patients who (1) died within 30 days of surgery or (2) were unable to communicate were excluded. Results: Clinically documented PLP occurred in 31 of 298 patients (10.4%; exact 95% CI, 7.2–14.4%) during hospitalization. In the prespecified primary model including age and preoperative pain, younger age (adjusted odds ratio (OR) 0.96 per 1-year increase, 95% confidence interval (CI) 0.93–0.99; p = 0.008) and preoperative pain (adjusted OR 16.34, 95% CI 3.75–71.24; p < 0.001) were associated with PLP. In an exploratory model additionally including postoperative pain on the day of surgery, postoperative pain was not independently associated with PLP. Firth penalized logistic regression yielded similar results. Conclusions: This study found a 10.4% incidence of clinically documented PLP during hospitalization after nontraumatic major LLA. Younger age and preoperative pain were associated with PLP, although the estimates should be interpreted cautiously because only 31 PLP events occurred.

Purpose It is not clear whether indirect laryngoscopes are superior to direct laryngoscopes for nasotracheal intubation and which laryngoscopes are better for nasotracheal intubation. We sought to undertake a ranking of the effectiveness of intubation devices in patients undergoing nasotracheal intubation. Methods We conducted a systematic review and network meta-analysis (NMA). We searched electronic databases for prospective randomized studies comparing different tracheal intubation devices in patients undergoing nasotracheal intubation. The primary outcome was intubation time. The secondary outcomes were first-attempt success rate, glottic visualization, use of Magill forceps, and the use of external laryngeal manipulation. We used DerSimonian and Laird random-effects models for statistical analysis. We performed frequentist network meta-analysis and generated network plots and network league tables. Results We included 22 studies comparing 10 types of devices. With the Macintosh direct laryngoscope as reference, six indirect laryngoscopes significantly reduced intubation time relative to the Macintosh laryngoscope. In the ranking of intubation time, the C-MAC® D-Blade (Karl Storz SE & Co. KG, Tuttlingen, Germany) had the highest P-score (0.98), and the Macintosh blade had the lowest P-score (0.07). In terms of first-attempt success rate, the C-MAC D-Blade had the highest (P-score, 0.78) and the Airway Scope™ S100 (Nihon Koden, Tokyo, Japan) the lowest (P-score, 0.06). Regarding glottic visualization, the Truview EVO2 (Truphatek International, Netanya, Israel) achieved the highest P-score (0.79), while the McCoy laryngoscope (Penlon, Abingdon, UK) had the lowest P-score (0.05). Conclusions In the present NMA to establish a ranking of the effectiveness of intubation devices in patients undergoing nasotracheal intubation, we found that most indirect laryngoscopes likely reduced intubation time, increased first-attempt success rates, and were more effective tracheal intubation devices for nasotracheal intubation compared with direct laryngoscopes The findings of the present a systematic review and NMA support a recommendation for the use of indirect laryngoscopes for nasotracheal intubation (very low certainty of evidence). Study registration PROSPERO (CRD42023446646); first submitted 20 July 2023.

Purpose: Hemodynamic response, particularly increased heart rate (HR) and blood pressure, can occur during tracheal intubation and is an adverse event to be avoided. The aim of this study was to use a network meta-analysis (NMA) to develop a ranking of hemodynamic responses (HR and mean blood pressure, MBP) after intubation of indirect and direct laryngoscopes in pediatric patients. Method: Studies were eligible for inclusion if they had a prospective randomized design, compared hemodynamic response (HR and MBP) to tracheal intubation between indirect and/or direct laryngoscopes, and were conducted in pediatric patients. The pooled difference between each intubation device’s intubation time is expressed as a weighted mean difference (WMD) of a 95% confidence interval (CI). The intubation time of the device was evaluated using P-scores calculated from the network point estimates and standard errors. A random-effects model was used when pooling effect sizes. We also analyzed intubation time as a related factor to hemodynamic responses. Results: From the electronic databases, we selected 16 trials for review. In a Macintosh-referenced analysis, Airtraq suppressed an increase of HR and MBP during tracheal intubation in pediatric patients significantly more than a Macintosh laryngoscope. (HR; WMD = −16.7, 95%CI −22.5 to −10.9, MBP; WMD = −8.57, 95%CI −10.9 to −6.27). Airtraq also topped the HR and MBP P-score rankings. The results of this study showed similar laryngoscopes in the top five rankings of P-scores (Airtraq, Coopdech video laryngoscope, Miller, C-MAC, Wis-Hipple) for HR and intubation time. Conclusions: We applied a network meta-analysis to create a consistent ranking of intubation devices that prevent hemodynamic changes during tracheal intubation in pediatric patients. In this NMA, Airtraq proved to be the best laryngoscope for preventing hemodynamic responses during tracheal intubation in pediatric patients. In the analysis of intubation time, Airtraq showed the shortest intubation time.

Postoperative nausea and vomiting (PONV) is a common adverse effect of anesthesia. Identifying risk factors for PONV is crucial because it is associated with a longer stay in the post-anesthesia care unit, readmissions, and perioperative costs. This retrospective study used artificial intelligence to analyze data of 37,548 adult patients (aged ≥20 years) who underwent surgery under general anesthesia at Tohoku University Hospital from January 1, 2010 to December 31, 2019. To evaluate PONV, patients who experienced nausea and/or vomiting or used antiemetics within 24 hours after surgery were extracted from postoperative medical and nursing records. We create a model that predicts probability of PONV using the gradient tree boosting model, which is a widely used machine learning algorithm in many applications due to its efficiency and accuracy. The model implementation used the LightGBM framework. Data were available for 33,676 patients. Total blood loss was identified as the strongest contributor to PONV, followed by sex, total infusion volume, and patient’s age. Other identified risk factors were duration of surgery (60–400 min), no blood transfusion, use of desflurane for maintenance of anesthesia, laparoscopic surgery, lateral positioning during surgery, propofol not used for maintenance of anesthesia, and epidural anesthesia at the lumbar level. The duration of anesthesia and the use of either sevoflurane or fentanyl were not identified as risk factors for PONV. We used artificial intelligence to evaluate the extent to which risk factors for PONV contribute to the development of PONV. Intraoperative total blood loss was identified as the potential risk factor most strongly associated with PONV, although it may correlate with duration of surgery, and insufficient circulating blood volume. The use of sevoflurane and fentanyl and the anesthesia time were not identified as risk factors for PONV in this study.

This meta-analysis was performed to determine whether an indirect laryngoscope is more advantageous than a direct laryngoscope for tracheal intubation in the setting of a difficult pediatric airway. Data on the intubation failure and intubation time during tracheal intubation were extracted from prospective and retrospective studies identified through a comprehensive literature search. Data from 10 individual articles (11 trials) were combined, and a DerSimonian and Laird random-effects model was used to calculate either the pooled relative risk (RR) or the weighted mean difference (WMD) and the corresponding 95% confidence interval (CI). Meta-analysis of the 10 articles indicated that the intubation failure of tracheal intubation with an indirect laryngoscope was not significantly different from that of a direct laryngoscope in patients with a difficult airway (RR 0.86, 95% CI 0.51–1.46; p = 0.59; Cochrane’s Q = 50.5; I² = 82%). Intubation time with an indirect laryngoscope was also similar to that with a direct laryngoscope (WMD 4.06 s; 95% CI −1.18–9.30; p = 0.13; Cochrane’s Q 39.8; I² = 85%). In conclusion, indirect laryngoscopes had the same intubation failure and intubation time as direct laryngoscopes in pediatric patients with a difficult airway. Currently, the benefits of indirect laryngoscopes have not been observed in the setting of a difficult pediatric airway.

Background: Persistent symptoms are reported in patients who survive the initial stage of COVID-19, often referred to as “long COVID” or “post-acute sequelae of SARS-CoV-2 infection” (PASC); however, evidence on their incidence is still lacking, and symptoms relevant to pain are yet to be assessed. Methods: A literature search was performed using the electronic databases PubMed, EMBASE, Scopus, and CHINAL and preprint servers MedRχiv and BioRχiv through January 15, 2021. The primary outcome was pain-related symptoms such as headache or myalgia. Secondary outcomes were symptoms relevant to pain (depression or muscle weakness) and symptoms frequently reported (anosmia and dyspnea). Incidence rates of symptoms were pooled using inverse variance methods with a DerSimonian-Laird random-effects model. The source of heterogeneity was explored using meta-regression, with follow-up period, age and sex as covariates. Results: In total, 38 studies including 19,460 patients were eligible. Eight pain-related symptoms and 26 other symptoms were identified. The highest pooled incidence among pain-related symptoms was chest pain (17%, 95% confidence interval [CI], 11%-24%), followed by headache (16%, 95% CI, 9%-27%), arthralgia (13%, 95% CI, 7%-24%), neuralgia (12%, 95% CI, 3%-38%) and abdominal pain (11%, 95% CI, 7%-16%). The highest pooled incidence among other symptoms was fatigue (44%, 95% CI, 32%-57%), followed by insomnia (27%, 95% CI, 10%-55%), dyspnea (26%, 95% CI, 17%-38%), weakness (25%, 95% CI, 8%-56%) and anosmia (19%, 95% CI, 13%-27%). Substantial heterogeneity was identified (I², 50–100%). Meta-regression analyses partially accounted for the source of heterogeneity, and yet, 53% of the symptoms remained unexplained. Conclusions: The current meta-analysis may provide a complete picture of incidence in PASC. It remains unclear, however, whether post-COVID symptoms progress or regress over time or to what extent PASC are associated with age or sex.

Purpose We sought to perform a systematic review and meta-analysis to determine whether indirect laryngoscopy has an advantage over direct laryngoscopy in terms of the tracheal intubation rate, glottic visualization, and intubation time when used by novice operators. Methods We extracted adult prospective randomized trials comparing tracheal intubation with indirect vs direct laryngoscopy in novice operators from electronic databases. We extracted the following data from the identified studies: success rate, glottic visualization, and intubation time. Data from each trial were combined via a random-effects model to calculate the pooled relative risk (RR) or weighted mean difference (WMD) with a 95% confidence interval (CI). We also performed a trial sequential analysis. Results We included 15 articles (17 trials) comprising 2,290 patients in the systematic review. Compared with the direct laryngoscopy, indirect laryngoscopy improved success rate (RR, 1.15; 95% CI, 1.07 to 1.24; P = 0.0002; I² = 88%), glottic visualization (RR, 1.76; 95% CI, 1.36 to 2.28; P < 0.001; I² = 85%), and intubation time (WMD, −9.06 sec; 95% CI, −16.4 to −1.76; P = 0.01; I² = 98%) in tracheal intubation. Trial sequential analysis showed that the total sample size was sufficient to analyze the success rate and intubation time. Conclusion In this systematic review, we found that the tracheal intubation success rate, glottic visualization, and intubation time were improved when novice operators used indirect laryngoscopy rather than direct laryngoscopy. Trial sequential analysis results indicated that the sample size was sufficient for examining the success rate and intubation time. Study registration PROSPERO (CRD42022309045); first registered 4 September 2022.