"Feed-and-wrap" technique versus deep sedation for neonatal magnetic resonance imaging: a retrospective comparative study.

OBJECTIVES: Neonatal MRI is usually performed under deep sedation, which is challenging-especially in low-weight premature patients. In addition, long-term side effects, such as neurotoxicity, are of concern. An alternative to sedation is to induce natural sleep by feeding and immobilising the child, the "feed-and-wrap" technique (FWT). The objective of this study was to evaluate differences in image quality between neonates examined under sedation and by using the FWT during the first four months of life. MATERIALS AND METHODS: We retrospectively assessed image quality (based on a 4-point semiquantitative scale) of all MRI examinations in neonates performed at our institution between July 2009 and August 2022. Differences in image quality between examinations under sedation versus FWT were evaluated. RESULTS: We included 432 consecutive patients, 243 (56%) using sedation and 189 (44%) using the FWT. Corrected age and body weight (mean ± SD: 3.7 ± 1.1 versus 4.5 ± 1.3 kg, p < 0.001) were significantly lower in the FWT group. The overall success rate in the FWT group was 95%. Image quality was slightly lower when using the FWT (mean ± SD: 3.7 ± 0.43 versus 3.96 ± 0.11, p < 0.001). Multivariate analysis showed a higher risk of acquiring sequences with diagnostic limitations in the FWT group (p < 0.001), increasing with corrected age (p = 0.048). CONCLUSION: The FWT is a highly successful method to perform MRI scans in term and preterm neonates. Overall image quality is only slightly lower than under sedation. Especially in immature low-weight preterm patients, the FWT is a reliable option to perform MRI studies without exposing the child to risks associated with sedation. CLINICAL RELEVANCE STATEMENT: The "feed-and-wrap" technique enables high-quality MRI examinations in neonates, including low-weight premature patients. Deep sedation for diagnostic MRI procedures in this age group, which has the risk of short- and long-term complications, can often be avoided. KEY POINTS: Deeply sedating neonates for MR examinations comes with risks. Image quality is only slightly lower when using the "feed-and-wrap" technique. The "feed-and-wrap" technique is feasible even in low-weight premature infants.

An update on red blood cell transfusion in non-cardiac thoracic surgery.

Background: The aim of this study was to evaluate risk factors for red blood cell (RBC) transfusion in non-cardiac thoracic surgery. Methods: All patients undergoing non-cardiac thoracic surgery in a single tertiary referral center between January and December 2021 were eligible for this study. Data on blood requests and perioperative RBC transfusion were retrospectively analyzed. Results: A total of 379 patients were included, of whom 275 (72.6%) underwent elective surgery. The overall RBC transfusion rate was 7.4% (elective cases: 2.5%, non-elective cases: 20.2%). Patients with lung resections required transfusion in 2.4% of the cases versus 44.7% in patients undergoing surgery for empyema. In multivariable analysis, empyema (P=0.001), open surgery (P<0.001), low preoperative hemoglobin (P=0.001), and old age (P=0.013) were independent risk factors for RBC transfusion. The best predictor of blood transfusion was preoperative hemoglobin with a cut-off value <10.4 g/dL (sensitivity 82.1%, specificity 86.3%, area under the curve 0.882). Conclusions: The rate of RBC transfusion in current non-cardiac thoracic surgery is low, especially in elective lung resections. In urgent cases and open surgery, transfusion rates remain high, particularly in empyema cases. Preoperative requesting of RBC units should be tailored to patient-specific risk factors.

Video Laryngoscopy Using King Vision™ aBlade™ and Direct Laryngoscopy in Paediatric Airway Management: A Randomized Controlled Study about Device Learning by Anaesthesia Residents.

Background: Airway management in children is challenging due to anatomical and physiological differences. This randomized trial investigates whether anaesthesia residents can intubate the paediatric trachea more quickly and with a higher success rate using the King Vision™ Paediatric aBlade™ video laryngoscope (KVL) compared to conventional direct laryngoscopy (DL). Methods: Eleven anaesthesia residents (mean age: 31 years, mean training status 47 months) were each asked to perform intubations with the KVL and DL in paediatric patients. The primary outcome was the first-attempt success rate. Secondary outcomes were the time to best view (TTBV), time to placement of the tracheal tube (TTP), time to ventilation (TTV), and participant-reported ease of use on a Likert scale. Results: 105 intubations with the KVL and 106 DL were performed by the residents. The success rate on the first attempt with the KVL was 81%, and the success rate on the first attempt within a given time limit of 30 s was 45%, which was lower than with DL (93% and 77% with time limit, p < 0.01). The median TTBV [IQR] on the first attempt with KVL was 7 [5−10] s, the median TTP was 28 [19−44] s, and the median TTV was 51 [39−66] s. DL-mediated intubation was significantly faster (TTP: 17 [13−23] s; p < 0.0001 and TTV: 34 [28−44] s; p < 0.001). Application of the KVL was rated as difficult or very difficult by 60% of the residents (DL: 5%). Conclusion: In contrast to promising data on the paediatric training manikin, residents took longer to intubate the airway in children with the KVL and were less successful compared to the DL. Therefore, the KVL should not be recommended for learning paediatric intubation by residents.

[Comparison of the Accuracy of the Measurement of Fetal Hemoglobin by Blood Gas Analysis and by Laboratory Gold Standard: a Prospective Diagnostic Study]. / Prospektiver Vergleich der Genauigkeit der Messung des fetalen Hämoglobins mittels Blutgasanalyse mit dem Goldstandard bei früh- und reifgeborenen Neugeborenen.

BACKGROUND: In neonatologic clinical practice and research the percentage of fetal hemoglobin (HbF) of total hemoglobin can be of interest. Blood gas analyzers offer the measurement of HbF. However, it is not known if results are accurate enough to apply in clinical decision-making or scientific questions. In this prospective diagnostic study, we examined the accuracy of HbF measurement by a blood gas analyzer. METHODS: On a neonatal intensive care and neonatal ward, the percentage of HbF was measured using both the laboratory gold standard (HbFlab, reference method) and the blood gas analyzer (HbFgas) (ABL 800 Flex, Radiometer). Agreement of HbFlab and HbFgas was assessed by the Bland-Altman method including bias and limits of agreement and by calculation of the root mean square error (RMSE). RESULTS: Thirty-five measurements in 23 term and preterm infants with a median body weight of 2190 g (min-max 967-3800 g) and a median postmenstrual age of 36+1 weeks (min-max 29+6-43+2) were performed. The Bland-Altman diagram for the measurement of HbF(gas) versus HbF(lab) shows an overestimation of HbF by the blood gas analyzer (bias 9.3%, limits of agreement 1 to 17.6%). RMSE was 10.2%; 45.7% of HbFgas measurements were >10% out of range from HbFlab. There was no influence of age, body temperature or oxygen saturation on the bias (p=0,132; p=0,194; p=0,970), but bias increased with increasing HbFlab (Pearson correlation r=0,426; p=0,011). CONCLUSION: The measurement of HbF in term and preterm infants by a blood gas analyzer lacked sufficient agreement with that of the reference method to recommend this application for clinical decision-making or scientific purposes.

The Orogastric Tube Guide® as a novel strategy for gastric tube insertion: a prospective, randomized controlled clinical trial.

BACKGROUND: Gastric tube insertion, either orally or nasally, is daily practice in anesthesia and intensive care. "Blind" insertion represents the common conventional method and is associated with low first-pass success and frequent complications. This trial aimed to evaluate the novel gastric tube guide as a rigid conduit in regard to insertion success rate, time required and associated complications versus the conventional "blind" insertion method. We hypothesized that the insertion success rate is higher using the Orogastric tube guide. METHODS: This trial was approved by ethics committee prior to patient recruitment. In a randomized order, anesthetists performed oral insertion of a gastric tube either with the Orogastric tube guide (GTG) or by conventional "blind" technique (CONV) in elective surgical patients. Exclusion criteria were defined as age under 18 years, pregnancy, emergency surgery and patients without indication for tracheal intubation and gastric tube insertion. RESULTS: We examined 151 patients (GTG, N.=71; CONV, N.=80). The success rate was higher with the GTG compared to the conventional method (69/71 (97%) vs. 61/80 (76%); P<0.001). The median insertion time was 25 s (IQR 20-39) using the GTG and 31 s (IQR 24-58; P=0.027) with the conventional method. We found no differences with regard to complications between the groups (P=0.54). CONCLUSIONS: Our findings suggest that the use of the GTG facilitates and fastens orogastric tube placement in anesthetized patients and thereby constitutes a benefit in clinical routine.

A comparison of two hyperangulated video laryngoscope blades to direct laryngoscopy in a simulated infant airway: a bicentric, comparative, randomized manikin study.

BACKGROUND: In infants, securing the airway is time-critical because of anatomical and physiological differences related to airway management in children less than 1 year old. The aim of this study was to compare the time to ventilation using two different hyperangulated video laryngoscope blades with the time to ventilation via conventional direct laryngoscopy in a normal airway [NA] and in a simulated difficult airway [DA]. METHODS: This study was a comparative, bicentric, open-label, randomized controlled evaluation. An infant high-fidelity simulator (SimBaby™; Laerdal® Medical, Stavanger, Norway) was used, and two scenarios were proposed, as follows: NA and DA evoked with tongue edema and cervical collar. After theoretical and practical briefing, each participant compared in the two airway scenarios the novel King Vision™ Pediatric aBlade (KV) (Ambu® A/S, Bad Nauheim, Germany) video laryngoscope and the C-MAC™ D-blade Ped (DB) (Karl Storz® SE & Co. KG, Tuttlingen, Germany) video laryngoscope to conventional laryngoscopy using the Miller Blade (MiB) and the Macintosh Blade (MaB) in a random sequence. RESULTS: Eighty physicians (65 AN and 15 PCCM staff) were included. In the NA scenario, the median [IQR] time to successful time to ventilation (TTV) was significantly shorter for the KV at 13 s [12-15 s] than for the MaB at 14.5 s [13-16 s], DB at 14.5 s [13-16] and MiB at 16 s [14-19] (p < 0.001). In DA, the KV also shortened TTV to 14 s [13-16], whereas TTV was 23 s with the MaB [20-26], 19 s with the DB [16-21], and 27 s with the MiB [22-31] (p < 0.001). There were no differences in first-pass intubation success rates (FPAs) between hyperangulated blades and direct laryngoscopes in NA. In DA, the hyperangulated blades enabled 92 (DB) to 100% (KV) FPAs compared with 65 (MiB) to 76% (MaB) for conventional laryngoscopy (p < 0.001). CONCLUSION: Video laryngoscopes with hyperangulated blades were associated with shorter TTV in normal and difficult infant airway situations. The higher FPAs of hyperangulated blades in DA may avoid desaturations and decrease adverse events in pediatric airway management.

Combination of STOP-Bang Score with Mallampati Score fails to improve specificity in the prediction of sleep-disordered breathing.

BACKGROUND: Sleep-disordered breathing (SDB) is closely associated with perioperative complications. STOP-Bang score was validated for preoperative screening of SDB. However, STOP-Bang Score lacks adequately high specificity. We aimed to improve it by combining it with the Mallampati Score. METHODS: The study included 347 patients, in which we assessed both STOP-Bang and Mallampati scores. Overnight oxygen saturation was measured to calculate ODI4%. We calculated the sensitivity and specificity for AHI and ODI4% of both scores separately and in combination. RESULTS: We found that STOP-Bang Score ≥3 was present in 71%, ODI≥5/h (AHI ≥5/h) in 42.6% (39.3%) and ODI≥15/h (AHI ≥15/h) in 13.5% (17.8%). For ODI4%≥5/h (AHI ≥5/h) we observed in men a response rate for sensitivity and specificity of STOP-Bang of 94.5% and 17.1% (90.9% and 12.5%) and in women 66% and 51% (57.8% and 46.9%). For ODI4%≥15/h (AHI≥15/h) it was 92% and 12% (84.6% and 10.3%) and 93% and 49% (75% and 49.2%). For ODI4%≥5 (AHI≥5) sensitivity and specificity of Mallampati score were in men 38.4% and 78.6% (27.3% and 68.2%) and in women 25% and 82.7% (21.9% and 81.3%), for ODI≥15 (AHI ≥15/h) 38.5% and 71.8% (26.9% and 69.2%) and 33.3% and 81.4% (17.9% and 79.6%). In combination, for ODI4%≥15/h, we found sensitivity in men to be 92.3% and in women 93.3%, specificity 10.3% and 41.4%. CONCLUSIONS: STOP-Bang Score combined with Mallampati Score fails to increase specificity. Low specificity should be considered when using both scores for preoperative screening of SDB.

Supplemental Interscalene Blockade to General Anesthesia for Shoulder Arthroscopy: Effects on Fast Track Capability, Analgesic Quality, and Lung Function.

BACKGROUND: After shoulder surgery performed in patients with interscalene nerve block (without general anesthesia), fast track capability and postoperative pain management in the PACU are improved compared with general anesthesia alone. However, it is not known if these evidence-based benefits still exist when the interscalene block is combined with general anesthesia. METHODS: We retrospectively analyzed a prospective cohort data set of 159 patients undergoing shoulder arthroscopy with general anesthesia alone (n = 60) or combined with an interscalene nerve block catheter (n = 99) for fast track capability time. Moreover, comparisons were made for VAS scores, analgesic consumption in the PACU, pain management, and lung function measurements. RESULTS: The groups did not differ in mean time to fast track capability (22 versus 22 min). Opioid consumption in PACU was significantly less in the interscalene group, who had significantly better VAS scores during PACU stay. Patients receiving interscalene blockade had a significantly impaired lung function postoperatively, although this did not affect postoperative recovery and had no impact on PACU times. CONCLUSION: The addition of interscalene block to general anesthesia for shoulder arthroscopy did not enhance fast track capability. Pain management and VAS scores were improved in the interscalene nerve block group.

[Is daytime sleepiness a sufficient predictor of sleep-disordered breathing during pre-anesthesia consultation?]. / "Tagesschläfrigkeit" als Prädiktor für schlafbezogene Atmungsstörungen (SBAS)--ist eine präoperative Evaluation sinnvoll?

BACKGROUND: Sleep-disordered breathing (SDB) is associated with increased rate of perioperative complications. Daytime sleepiness is a frequent symptom of SDB. Thus, aim of the present study was to evaluate whether preoperative assessment of daytime sleepiness would be eligible for sufficient prediction of SDB. METHODS: Patients before scheduled surgery were prospectively recruited and asked to answer a standardized sleep questionnaire (Epworth Sleepiness Scale; ESS). The night before surgery, sleep polygraphy was performed and the oxygen desaturation index 4% (ODI 4%) was calculated. RESULTS: Data of 363 patients (190 men and 173 women) were finally analyzed. Regarding risk assessment, 42 patients had ASA grade 1, 192 patients had ASA grade 2, 123 patients had ASA grade 3 and 6 patients had ASA grade 4. Mean Body Mass Index was 27.9 ± 5.1 kg/m2, mean age was 59.2 ± 13.3 years and mean ESS score was 5.7 ± 3.4. Clinical relevant daytime sleepiness (ESS ≥ 11) was found in 32 patients (9%). In 11 patients (34%) with ESS ≥ 11, ODI 4% ≥ 5/h was calculated whereas in 21 patients with ESS ≥ 11 (66%), ODI 4% < 5/h was found. Odds ratio between ODI 4% ≥ 5/h and ESS ≥ 11 was 0.919 (CI 0.85-0.99, p = 0.038). CONCLUSION: In non-obese patients, daytime sleepiness is a rare event and is not associated with SDB. Thus, daytime sleepiness is not eligible for the preoperative SDB screening.

Changes in cerebral oxygen saturation following prone positioning for orthopaedic surgery under general anaesthesia: a prospective observational study.

BACKGROUND: Prone positioning is often necessary in orthopaedic surgery. The prone position, however, may result in impaired cerebral venous drainage with a subsequent reduction in cerebral perfusion. As a consequence, cerebral hypoxia may occur with the potential for neurological impairment. OBJECTIVE: We assessed the changes in cerebral oxygen saturation with near-infrared spectroscopy using two different monitors after positioning the patient from supine to prone. DESIGN: Prospective observational study. SETTING: Primary Care University Hospital, from May 2010 to February 2011. PARTICIPANTS: Forty patients undergoing general anaesthetic procedures, of which 35 completed the investigation. Similar measurements were done in 35 volunteers, who were studied while awake. INTERVENTIONS: Near-infrared spectroscopy was measured throughout anaesthesia using INVOS (a trend monitor using two infrared wavelengths) for one hemisphere and FORE-SIGHT (a monitor using four wavelengths of laser light to calculate absolute oxygen saturation) for the other hemisphere in an alternate randomisation pattern. OUTCOME MEASUREMENTS: The primary outcome was a change in cerebral oxygen saturation of more than 5% during prone positioning. A comparison with the changes obtained in awake volunteers following similar positioning was also made. RESULTS: Cerebral oxygen saturation increased during prone positioning with INVOS 0.032% per minute (P < 0.01) and with FORE-SIGHT 0.032% per minute (P < 0.01) in anaesthetised patients. Awake volunteers showed an increase of 0.171% per minute (INVOS) and 0.082% per minute (FORE-SIGHT) during prone positioning. Comparison of INVOS with FORE-SIGHT showed a good association, with a gradient of 0.80% per 1% change (P < 0.01). CONCLUSION: Both monitors detected a small increase in cerebral oxygen saturation of less than 5% in patients undergoing orthopaedic surgery in the prone position and in awake volunteers. This small increase is of limited clinical relevance and prone positioning may be regarded as safe in terms of the maintenance of cerebral oxygen saturation. TRIAL REGISTRATION: clinicaltrials.gov identifier: NCT01275898.

Impact of regional femoral nerve block during general anesthesia for hip arthoplasty on blood pressure, heart rate and pain control: A randomized controlled study.

BACKGROUND: Adequate pain management is essential for preventing hemodynamic instability which can affect the perfusion of vital organs during the perioperative period, particularly in geriatric patients. For hip arthroplasty, peripheral nerve block is frequently used, limiting the adverse effects of opioid and non-opioid analgesics. OBJECTIVE: The aim was to survey the impact of a supplementary single shot femoral nerve block (FNB) on hemodynamic stability and pain level. METHODS: After registration at German Clinical Trial Register (DRKS-ID): DRKS00000752. and Ethics Committee approval (University Hospital of Marburg), 80 patients who underwent elective hip surgery were included. Half of them were randomly assigned to receive a FNB followed by general anesthesia; a control group received only general anesthesia as standard procedure (STD). Blood pressure and heart rate were measured and recorded every five minutes during surgery and stay at the postanesthesia care unit (PACU). RESULTS: Fifty-two patients were included for statistical analysis. The FNB group had significantly lower systolic blood pressures during and after surgery and lower diastolic blood pressure postoperatively, heart rate, as well as opioid and non-steroidal anti-inflammatory consumption. CONCLUSIONS: Femoral nerve block improved perioperative hemodynamic stability mostly likely attributable to an overall reduced sympathico adrenergic tone.

Occurrence of rapid eye movement sleep deprivation after surgery under regional anesthesia.

BACKGROUND: Sleep disturbances after general surgery have been described. In this study, we assessed rapid eye movement (REM) sleep in patients undergoing knee replacement surgery using a regional anesthetic technique. METHODS: Ambulatory polysomnography (PSG) was performed on 3 nights: the night before surgery (PSG1), the first night after surgery (PSG2), and the fifth postoperative night (PSG3). Postoperative analgesia was maintained with peripheral nerve catheters for the first 3 days and with oral opioids thereafter. In addition, nonsteroidal antiinflammatory drugs were administered. Postoperative pain was monitored using a visual analog scale. RESULTS: PSG was performed in 12 patients, 6 men and 6 women, with a mean age of 61 (±12) years. REM sleep was reduced from PSG1 (median 16.4%) to PSG2 (median 6.3%; P = 0.02). The Hodges-Lehmann estimate for the median reduction is -7.8% (95% confidence interval -14.8% to -0.7%). During PSG3, significantly more REM sleep was detected (median 15.4%) compared with PSG2 (P = 0.01). The Hodges-Lehmann estimate for this median increase is 10.0% (95% confidence interval 1.7%-25.3%). CONCLUSION: Postoperative reduction of REM sleep also occurs after surgery and regional anesthesia.

Short term non-invasive ventilation post-surgery improves arterial blood-gases in obese subjects compared to supplemental oxygen delivery - a randomized controlled trial.

BACKGROUND: In the immediate postoperative period, obese patients are more likely to exhibit hypoxaemia due to atelectasis and impaired respiratory mechanics, changes which can be attenuated by non-invasive ventilation (NIV). The aim of the study was to evaluate the duration of any effects of early initiation of short term pressure support NIV vs. traditional oxygen delivery via venturi mask in obese patients during their stay in the PACU. METHODS: After ethics committee approval and informed consent, we prospectively studied 60 obese patients (BMI 30-45) undergoing minor peripheral surgery. Half were randomly assigned to receive short term NIV during their PACU stay, while the others received routine treatment (supplemental oxygen via venturi mask). Premedication, general anaesthesia and respiratory settings were standardized. We measured arterial oxygen saturation by pulse oximetry and blood gas analysis on air breathing. Inspiratory and expiratory lung function was measured preoperatively (baseline) and at 10 min, 1 h, 2 h, 6 h and 24 h after extubation, with the patient supine, in a 30 degrees head-up position. The two groups were compared using repeated-measure analysis of variance (ANOVA) and t-test analysis. Statistical significance was considered to be P < 0.05. RESULTS: There were no differences at the first assessment. During the PACU stay, pulmonary function in the NIV group was significantly better than in the controls (p < 0.0001). Blood gases and the alveolar to arterial oxygen partial pressure difference were also better (p < 0.03), but with the addition that overall improvements are of questionable clinical relevance. These effects persisted for at least 24 hours after surgery (p < 0.05). CONCLUSION: Early initiation of short term NIV during in the PACU promotes more rapid recovery of postoperative lung function and oxygenation in the obese. The effect lasted 24 hours after discontinuation of NIV. Patient selection is necessary in order to establish clinically relevant improvements. TRIAL REGISTRATION#: DRKS00000751; http://www.germanctr.de.

Forced needle advancement during needle-nerve contact in a porcine model: histological outcome.

BACKGROUND: In this study, we determined whether needle advancement during needle-nerve contact (forced needle-nerve contact) is associated with a higher risk of nerve injury compared with needle-nerve contact without needle advancement (nonforced needle-nerve contact). METHODS: In 8 anesthetized pigs, the brachial plexus nerves underwent forced (0.15 Newton) or nonforced (0.0 Newton) needle-nerve contact without nerve penetration. The grade of nerve injury was histologically assessed using an objective score ranging from 0 (no injury) to 4 (severe injury). RESULTS: Sixty-nine nerves, including controls, were examined. Histology revealed a significant difference between forced and nonforced needle-nerve contact (median [interquartile range] 3 [2-4] vs 2 [1-2]; P = 0.004). Myelin damage and intraneural hematoma occurred only after forced needle-nerve contact. CONCLUSIONS: The severity of structural nerve injury after needle-nerve contact was directly related to force exposure via needle advancement.

[Overnight documentation of respiratory sounds in patients with chronic sinusitis]. / Langzeitregistrierung von Atemgeräuschen im Schlaf bei Patienten mit chronischer Sinusitis.

BACKGROUND AND PURPOSE: Nocturnal worsening of respiration in patients with chronic sinusitis is most likely induced by creeping of mucus from the parasinuses down to the pharynx. The aim of this study was to document respiratory symptoms such as deglutition, wheezing and cough in patients with chronic sinusitis using long-term recording of respiratory sounds. PATIENTS AND METHODS: According to the CORSA (computerized respiratory sound analysis) criteria, long-term recording of respiratory sounds was performed in 20 patients with chronic sinusitis. RESULTS: Wheezing was detected in 30%, (excessive) cough was found in 40%. Deglutition was measured with a frequency of ten per hour. CONCLUSION: Long-term recording of respiratory sounds is a practical and noninvasive method for the documentation of clinical symptoms like wheezing, coughing and deglutition during sleep.

Ambient temperature impacts on pH of exhaled breath condensate.

BACKGROUND AND OBJECTIVE: Analysis of exhaled breath condensate (EBC) pH is a non-invasive method to study airway inflammation. Low pH is correlated with inflammatory diseases like asthma and COPD. The aim of this study was to assess the influence of measurement temperature on pH values of EBC. METHODS: EBC was collected using the RTube in 10 healthy non-smoking controls, 10 smokers before and after cigarette smoking, 10 stable COPD patients and 10 patients with exacerbated COPD. pH was determined directly after degassing at temperatures of 23 degrees C and 37 degrees C. RESULTS: When comparing all groups pH was significantly (P = 0.0002) higher (mean +/- SD 7.88 +/- 0.92) at 37 degrees C as compared with 23 degrees C (7.44 +/- 0.90). Specifically, at 23 degrees C pH was significantly lower in the group of exacerbated COPD (6.78 +/- 1.27) and healthy non-smoking controls (8.04 +/- 0.39). In contrast, subgroup analysis of values assessed at 37 degrees C did not display significant differences. CONCLUSIONS: Our data indicate a considerable influence of temperature on pH values in EBC. Thus the temperature at which pH measurements in EBC studies are performed should be declared.

The influence of perioperative oxygen concentration on postoperative lung function in moderately obese adults.

BACKGROUND AND OBJECTIVE: Obesity aggravates the negative effects of general anaesthesia and surgery on the respiratory system, resulting in decreased functional residual capacity and expiratory reserve volume, and increased atelectasis and ventilation/perfusion (Va/Q) mismatch. High-inspired oxygen concentrations also promote atelectasis. This study compares the effects of perioperative inspired low-oxygen and high-oxygen concentrations on postoperative lung function and pulse oximetry values in moderately obese patients (BMI 25-35). METHODS: We prospectively studied 142 overweight patients, BMI 25-35, undergoing minor peripheral surgery; they were randomly allocated to receive either low-inspired or high-inspired oxygen concentrations during general anaesthesia. Premedication, general anaesthesia and respiratory patterns were standardized. Arterial oxygen saturation (pulse oximetry) was measured on air breathing. Inspiratory and expiratory lung functions were measured preoperatively (baseline) and at 10 min, 0.5, 2 and 24 h after extubation with the patient supine, in a 30 degrees head-up position. The two groups were compared using repeated-measure analysis of variance and t-test analysis. RESULTS: The low-inspired oxygen group had significantly better arterial saturation during the first 24 h (P < 0.01). Mid-expiratory flow 25 values indicating small airway collapse were significantly better in the low-oxygen group at all measurements (P < 0.05). CONCLUSION: We conclude that postoperative lung function and arterial saturation is better preserved by a low-oxygen strategy, although it is not clear whether this has clinical relevance for the prevention of postoperative pulmonary complications.

Short-term respiratory physical therapy treatment in the PACU and influence on postoperative lung function in obese adults.

BACKGROUND: Even several days after surgery, obese patients exhibit a measureable amount of atelectasis and thus are predisposed to postoperative pulmonary complications. Particularly in ambulatory surgery, rapid recovery of pulmonary function is desired to ensure early discharge of the obese patient. In this study, we wanted to evaluate intensive short-term respiratory physical therapy treatment (incentive spirometry) in the postanesthesia care unit (PACU) and its impact on pulmonary function in the obese. METHODS: After ethics committee approval and informed consent, we prospectively studied 60 obese patients (BMI 30-40) undergoing minor peripheral surgery, half of which were randomly assigned to receive respiratory physiotherapy during their PACU stay, while the others received routine treatment. Premedication, general anesthesia, and respiratory settings were standardized. We measured arterial oxygen saturation by pulse oximetry on air breathing. Inspiratory and expiratory lung functions were measured preoperatively (baseline) and at 10 min, 1, 2, 6, and 24 h after extubation, with the patient supine, in a 30 degrees head-up position. The two groups were compared using repeated-measure analysis of variance and t test analysis. Statistical significance was considered to be P < 0.05. RESULTS: There were no differences at the first assessment, but, during the PACU stay, pulmonary function in the physiotherapy group was significantly better than the controls' (p < 0.0001), an effect which persisted for at least 24 h after surgery (p < 0.009). CONCLUSION: Short-term respiratory physiotherapy during the PACU stay promotes more rapid recovery of postoperative lung function in the obese during the first 24 h.

Mobile nocturnal long-term monitoring of wheezing and cough.

Changes in normal lung sounds are an important sign of pathophysiological processes in the bronchial system and lung tissue. For the diagnosis of bronchial asthma, coughing and wheezing are important symptoms that indicate the existence of obstruction. In particular, nocturnal long-term acoustic monitoring and assessment make sense for qualitative and quantitative detection and documentation. Previous methods used for lung function diagnosis require active patient cooperation that is not possible during sleep. We developed a mobile device based on the CORSA standard that allows the recording of respiratory sounds throughout the night. To date, we have recorded 133 patients with different diagnoses (80 male, 53 female), of whom 38 were children. In 68 of the patients we could detect cough events and in 87 we detected wheezing. The recording method was tolerated by all participating adults and children. Our mobile system allows non-invasive and cooperation-independent nocturnal monitoring of acoustic symptoms in the domestic environment, especially at night, when most ailments occur.