Non-medical risk factors associated with postponing elective surgery: a prospective observational study

Background

Operation room (OR) planning is a complex process, especially in large hospitals with high rates of unplanned emergency procedures. Postponing elective surgery in order to provide capacity for emergency operations is inevitable at times. Elderly patients, residents of nursing homes, women, patients with low socioeconomic status and ethnic minorities are at risk for undertreatment in other contexts, as suggested by reports in the medical literature. We hypothesized that specific patient groups could be at higher risk for having their elective surgery rescheduled for non-medical reasons.

Methods

In this single center, prospective observational trial, we analysed 2519 patients undergoing elective surgery from October 2018 to May 2019. A 14-item questionnaire was handed out to illicit patient details. Additional characteristics were collected using electronic patient records. Information on the timely performance of the scheduled surgery was obtained using the OR’s patient data management system. 6.45% of all planned procedures analysed were postponed. Association of specific variables with postponement rates were analysed using the Mann–Whitney U test and Fisher's exact test/χ²-test.

Results

Significantly higher rates of postponing elective surgery were found in elderly patients. No significant differences in postponing rates were found for the variables gender, nationality (Germany, EU, non-EU), native language, professional medical background and level of education. Significantly lower rescheduling rates were found in patients with ties to hospital staff and in patients with a private health insurer.

Conclusions

Elderly patients, retirees and nursing home residents seem to be at higher risk for having their elective surgery rescheduled. However, owing to the study design, causality could not be proven. Our findings raise concern about possible undertreatment of these patient groups and provide data on short-term postponement of elective surgery.

Trial registration DRKS00015836. Retrospectively registered.

Procedural times in early non-intubated VATS program - a propensity score analysis

BACKGROUND

Non-intubated video-assisted thoracic surgery (NiVATS) has been introduced to surgical medicine in order to reduce the invasiveness of anesthetic procedures and avoid adverse effects of intubation and one-lung ventilation (OLV). The aim of this study is to determine the time effectiveness of a NiVATS program compared to conventional OLV.

METHODS

This retrospective analysis included all patients in Leipzig University Hospital that needed minor VATS surgery between November 2016 and October 2019 constituting a NiVATS (n = 67) and an OLV (n = 36) group. Perioperative data was matched via propensity score analysis, identifying two comparable groups with 23 patients. Matched pairs were compared via t-Test.

RESULTS

Patients in NiVATS and OLV group show no significant differences other than the type of surgical procedure performed. Wedge resection was performed significantly more often under NiVATS conditions than with OLV (p = 0,043). Recovery time was significantly reduced by 7 min (p = 0,000) in the NiVATS group. There was no significant difference in the time for induction of anesthesia, duration of surgical procedure or overall procedural time.

CONCLUSIONS

Recovery time was significantly shorter in NiVATS, but this effect disappeared when extrapolated to total procedural time. Even during the implementation phase of NiVATS programs, no extension of procedural times occurs.

Increasing efficiency by optimizing table position for elective primary THA and TKA: a prospective monocentric pilot study

Introduction

Hip and knee arthroplasties are very frequently performed surgeries with high quality standards and continuous optimization potential. Intraoperative processes can be standardized and simplified by optimization of table setups in the operating room to improve the quality and to increase efficiency.

Patients and methods

The existing surgical setups for primary hip and knee arthroplasties in a university maximum care hospital with endoprosthesis center were simulated and analysed with a computer program and optimized setup suggestions were worked out, based on handover times, walking distance and ergonomic aspects determined in the program. In a prospective monocentric analysis, primary hip arthroplasties and knee arthroplasties were examined in currently used and in the new optimized setups (standard procedure according to in-house SOP, senior and main surgeons, no assistants). The surgeries were externally and independently supervised and analysed, whereby the time between incision and suture beginning, handovers per minute and handover times were documented, amongst other things. In addition, an evaluation sheet, which showed the satisfaction with the new setup, was filled by the surgical team.

Results

In the period from April 2016 to December 2018, 19 hip arthroplasties in currently used and 15 in the new optimized setup as well as 9 knee arthroplasties in currently used and 13 in the new setup were performed. Attention was paid to constant conditions in the compared groups and disruptive factors (assisted surgeries, complex surgeries, different cementings, etc.) were excluded. In the group of hip arthroplasties, the handover times were significantly different (old 1.82 +/− 1.43 s.; new 1.08 +/− 0.78 s.; p <0.001), as well as the handovers per minute (old 1.62 +/− 0.45 handovers/min.; new 2.10 +/− 0.32 handovers/min.; p = 0,001). The time between incision and suture beginning indicated no significant difference (old 53.89 +/− 18.92 min.; new 49.73 +/− 12.18 min; p = 0.466): During the knee arthroplasties, handovers per minute were significantly different (old 1.83 +/− 0.38 handovers/min.; new 2.40 +/− 0.35 handovers/min.; p = 0.002). The time between incision and suture beginning (old 71.11 +/− 20.72 min.; new 70.69 +/− 17.12 min.; p = 0.959) and the handover times (old 1.06 +/− 0.64 s.; new 0.91 +/− 0.59 s.; p = 0.152) indicated no significant difference. The evaluation of the questionnaires showed a significant difference (p < 0.001) in the group of hip arthroplasties in the category “visibility”. For the knee arthroplasties, all items except “visibility” (p = 0.261) differed significantly. Overall, a high level of staff satisfaction with the new setup was achieved.

Conclusions

In both groups, more handovers per minute could be achieved in the optimized setup and in the group of the hip arthroplasties, the handover times were significantly faster. The evaluation sheet showed a high satisfaction of the surgical staff with the new setup. No reduction of the time between incision and suture beginning could be determined. This can be attributed to a certain training effect, the adjustment to the setup modification and the low number of cases. The new setup offers a practical alternative for hip arthroplasties as well as for knee arthroplasties as it optimizes the events in the operating room in many ways. For example, there were more handovers per minute possible and passing of the surgical instruments free from interferences. Moreover, it increases the efficiency and achieves a high satisfaction of the staff.

Automated External Defibrillator Use for In-Hospital Emergency Management

The in-hospital spread of automated external defibrillators (AEDs) is aimed to allow for a shock-delivery within three minutes. However, it has to be questioned if the implementation of AED alone really contributes to a ‘heart-safe hospital’. We performed a cohort study of 1008 in-hospital emergency calls in a university tertiary care hospital, analysing cardiopulmonary resuscitation (CPR) cases with and without AED use. In total, 484 patients (48%) had cardiac arrest and received CPR. Response time of the emergency team was 4.3 ± 4.0 minutes. Only 8% percent of the CPR cases had a shockable rhythm. In three of 43 placements a shock was delivered by the AED. There were no differences in survival between patients with CPR only and CPR with AED use. Our data do not support the use of an AED for in-hospital CPR if a professional response team is rapidly available.

Automated external defibrillator use for in-hospital emergency management

Summary

The in-hospital spread of automated external defibrillators (AEDs) is aimed to allow for a shock-delivery within three minutes. However, it has to be questioned if the implementation of AED alone really contributes to a ‘heart-safe hospital’.

Methods

Cohort study of 1008 in-hospital emergency calls in a university tertiary care hospital. Analysis of cardio-pulmonary resuscitation (CPR) cases with and without AED use.

Results

A number of 484 patients (48%) had cardiac arrest and received CPR. Response time of the emergency team was 4.3 ± 4.0 minutes. 8% percent of the CPR cases had a shockable rhythm. In only three cases of 43 placements a shock was delivered by the AED. There were no differences in survival between patients with CPR only and CPR with AED use.

Conclusion

Our data do not support the use of an AED for in-hospital CPR if a professional response team is rapidly available.

Lack of relationship between occupational workload and microscopic alterations in lumbar intervertebral disc disease

Objectives :

The study investigated the impact of occupational workloads on disc surgery specimens. We report the relationship between workload and histological features.

Methods :

Specimens were collected prospectively from patients suffering from lumbar disc prolapse (n=90) or spinal osteochondrosis (n=19). Histomorphology and occupational workload data and histomorphological features were evaluated. Occupational data were collected in a structured, standardized patient interview assessing lifting and carrying loads. In this way the exposure was assessed for each test subject's entire working life up to surgery.

Results :

There was no association between cumulative workload and histological patterns. In a subgroup of patients with a workload period of 12 months prior to surgery a relevant formation of chondrocyte clusters (p=0.055) was apparent. Chondrocyte cluster formation was found in 83% (n=74) of the prolapse patients and in 58% (n=11) of the osteochondrosis patients (p=0.02). Fibrocyte mediated scar formation was found in 55% of the prolapse patients and in 45% of the spinal stenosis patients. Chondrocyte clusters and their de novo collagen matrix did not integrate biomechanically sufficient with collagen fibers of the disc. Disintegration of clusters from disc matrix and formation of intra-discal sequesters were observed.

Conclusion :

Matrix degeneration was common but displayed no relationship to occupational workload or other histological features. Scar formation was observed in every second specimen. Regenerative chondrocyte cluster proliferation was a common feature in disc specimens and tended to be associated in patients with a workload one year before surgery.

Obesity in anesthesia and intensive care

Obesity is a global epidemic increasingly affecting management of anesthesia as well as intensive care medicine. Possible improvements in therapy require consideration of the specific pathophysiology of the obese, their concomitant diseases, and the complications associated with morbid obesity. Systematic assessment of perioperative risk factors is essential for an appropriate management. Paradoxically, overweight and moderately obese patients undergoing surgery have a lower risk when compared to patients with normal weight. The highest mortality and morbidity rates in this setting are reported for underweight and morbidly obese patients. The better chance of survival when compared to normal-weight individuals in the perioperative setting has been described the obesity paradox. In particular, the commitment of all involved physicians to improve all aspects of care will reduce the perioperative risk in obese patients. Physiological and pharmacological characteristics of the obese should also be considered. Furthermore, adequate technical equipment and practical skills of all members of the anesthesia team significantly contribute to risk reduction and therapeutic success in obese patients.

Pharmacokinetics and clinical toxicity of prilocaine and ropivacaine following combined drug administration in brachial plexus anesthesia

OBJECTIVE

Local anesthetics (LA) are often administered in combination for regional anesthesia in order to obtain the specific advantages (onset and duration of effect) of each drug. However, few data on the safety of such combinations are available and consequently plasma concentrations possibly associated with toxicity and interactions between the specific anesthetics are not sufficiently established. We measured pharmacokinetics and toxicity parameters of prilocaine and ropivacaine after combined use as single doses in brachial plexus blockade.

METHODS

In an open clinical study using a combined dose regime (300 mg prilocaine followed immediately by 75 mg ropivacaine) total plasma concentrations of prilocaine and ropivacaine were measured serially in 60 patients using a gas-chromatographic method. The data were analyzed regarding a relationship with central nervous and cardiovascular toxicity.

RESULTS

Following the administration in combination prilocaine and ropivacaine were rapidly absorbed. Mean prilocaine peak plasma concentrations (mean Cmax = 1.51 microg/ml) were measured between 15 and 30 min after injection. Highest ropivacaine plasma concentrations (mean Cmax = 1.12 microg/ml) were seen between 30 min and 1 hour after injection (calculated mean tmax = 44 min). One of 59 patients showed signs of myoclonus which were suspected of being due to intravascular injection. There was no relevant cardiovascular toxicity observed in terms of changes in the QRS complex, PQ interval prolongation, AV dissociation, occurrence of extrasystoles or sinus arrest. The pharmacokinetics of combined administration did not differ from those of prilocaine and ropivacaine given alone.

CONCLUSION

The use of a combined prilocaine/ ropivacaine (300 mg/75 mg) dose regimen in patients given single dose for brachial plexus blockade can generally be regarded as safe with regard to peak plasma concentrations and cardiovascular toxicity and this holds true for patients with a higher perioperative risk profile (ASA III grading, American Society of Anesthesiologists). The considerable inter-individual variation in LA peak plasma concentrations observed in our patients and the one case of suspected accidental intravascular injection, highlight the necessity of adequate monitoring of the patients undergoing LA injections.

[Principles and risks of electrosurgery]

Electrosurgical instruments are routinely used in many applications by the surgeon. In principle, high-frequency electrical currents are used by passing trough tissue for cutting and coagulation. The heat generated by the electrosurgical unit is proportional to the resistance and diameter of the tissue. There are two commonly used electrosurgical modalities: monopolar and bipolar. Since negative side-effects of electrosurgery are possible (e.g. burn, interaction with other electric devices) a proper knowledge of all staff involved in electrosurgery is warranted. In the context of a safe perioperative patient management the anesthesiologist should know basic principles of high-frequency surgery as well. This article describes the main aspects of electrosurgery for anesthesiologists.

Total dura substitute in the spine: double layer dural substitute made from polylactide layer and bovine pericardium

When there is significant loss of spinal dura mater, dural substitution with synthetic or allogenic materials is essential. In the case of laminectomy, mechanical protection and reformation of the dorsal spinal canal may be useful. This is a report on a patient with total dura loss through tumour atrophy of the dura and laminae. In order to reconstruct the dorsal face of the spinal canal a polylactide sheet was cut and shaped to fit the physiological contour. A bovine dura substitute was firmly attached and sutured to the inner surface of the polylactide shield. The implant was wedged in between the pedicles and the facet joints and resulted in a water-tight dura substitute maintaining the shape of the spinal canal and protecting it against mechanical forces and intradural scar formation.

Anaesthesia and cardiac contractility modulation

Chronic heart failure is known to be an important risk factor for adverse perioperative outcome in patients undergoing non-cardiac surgery. A promising new form of electric therapy is currently being used in a phase III trial in patients with severe chronic heart failure (cardiac contractility modulation). Cardiac contractility modulation is a non-pharmacological approach to improve Ca2+ effect on cardiac myofilaments using electric currents. The cardiac contractility modulation system used at present (OPTIMIZER III, Impulse Dynamics, Orangeburg, NY, USA) consists of a subcutaneously implanted pulse generator and three electrodes. As far as we know, cardiac contractility modulation therapy is a safe and feasible way of improving the systolic function of the heart in congestive heart failure patients. No pro-arrhythmic effects of this new therapy have been reported. The technique shows promise as an additive treatment for severe chronic heart failure. The perioperative and intraoperative management of patients should follow current cardiac pacemaker/implantable cardioverter defibrillator guidelines.

Auto fluorescence of intervertebral disc tissue: a new diagnostic tool

The paper reports on auto fluorescence phenomena of inter-vertebral human discs. It systematically investigates the auto fluorescence effects of ex vivo disc specimen and reports on surgical cases to demonstrate the potential value of the new method. The paper offers biologic explanations of the phenomenon and discusses the potential value of the UV auto fluorescence technique as a diagnostic tool. Intra- and postoperative observations are made by a surgical microscope with an integrated UV light source. Quantitative measurements were carried out using a photon counter and a spectrometer ex vivo. The auto fluorescence phenomenon allows the differentiation of traumatized and degenerated disc tissue intraoperatively in some cases, it allows the differentiation of bony and collagen endplate in cervical disc surgery. The source of the auto fluorescent light emission are amino acids of the collagen molecules. The proteoglycan components and the liquid components of the disc do not show relevant auto fluorescence. Emission wavelength of disc material is equivalent to color perception. It differs due to different collagen composition of the intervertebral disc components from yellow-green to blue-green and can be visualized in situ by naked eye.UV-auto fluorescence of inter-vertebral discs is a new clinical tool that has the potential to differentiate disc material from the anatomical surrounding, to distinguish between different fractions of the disc and to give information on the quality and status of the disc material. Since the technology has just emerged, it needs further investigations to quantify the clinical observations reported in this paper.

Olive oil based nutrition in multiple trauma patients: a pilot study

OBJECTIVE

A negative effect of hyperglycemia on clinical outcome has been proposed for patients treated under intensive care conditions. So far, however, the safety and effect of fat based nutrition regimen, especially of olive oil based emulsions, have not been systematically studied.

DESIGN AND SETTING

Prospective, open-labeled, randomized, pilot study in a 14-bed surgical intensive care unit.

PATIENTS AND INTERVENTIONS

Thirty-three consecutive, severe multiple trauma patients (injury severity score 31.6+/-11.5) were included; 18 (L group) received a parenteral lipid-based nutrition; 15 (G group) were given a standard parenteral glucose-based nutrition.

MEASUREMENTS AND RESULTS

The energy expenditure (EE) showed no difference between groups and no significant difference between the energy intake/EE ratio. The daily mean energy intake was lower in the L group (17.9+/-6.3 kcal/kg) than in the G group (22.3+/-4.2 kcal/kg). Triglycerides and nitrogen balance showed no significant differences between groups. The L group had significantly lower blood glucose (L 7.4+/-1.6, G 8.7+/-1.6 mmol/l), carbon dioxide production, and minute volume and shorter duration of mechanical ventilation (L 13.0+/-8.9, G 20.4+/-7.0 days), and stay in the ICU (L 17.9+/-11.2, G 25.1+/-7.0 days).

CONCLUSIONS

Our findings suggest a good tolerance, a decrease in blood glucose, clinically relevant shortening of ICU stay, and shorter time on mechanical ventilation for patients treated with olive oil based than with conventional glucose-heavy nutrition.

Electromyographic investigation on handling forces of mechanically counterbalanced and sensor-servomotor-supported surgical microscopes

BACKGROUND

Recent developments in sensor-servomotor-driven microscopes again initiated a discussion on the value of such technology for practical use in neurosurgery. The need for less force in moving a motor-supported microscope is advantageous. However, questions remain if well-known difficulties in the past such as resonance phenomenon, loss of natural feeling, and unequal handling forces in different situations have been overcome by the new generation of sensor-servo-supported surgical microscopes.

METHODS

Handling forces of a mechanically counterbalanced neurosurgical microscope (Zeiss NC4, Zeiss, Oberkochen, Germany) were compared with those of a sensor-servo-supported neurosurgical microscope (Moeller HiR 20-1000, Moeller, Wedel, Germany). Handling forces were correlated with the surface electromyogram measurement of the muscle activity of 4 neurosurgeons. The activity of the forearm muscles was measured while handling the 2 different microscopes in standardized tests.

RESULTS

The electrophysiologic measurement revealed that significantly less muscle activity was required to handle the sensor-servo-driven microscope in all directions. The untrained surgeons profited less than the skilled ones. Differences were most evident with disbalanced microscopes.

CONCLUSIONS

With this technology, the neurosurgeons exerted less effort, especially in strenuous test situations where the single-handed use of the microscope was mandatory. The reduced muscle forces that move the sensor-servo-type microscope and the continuously balanced state that might help prevent unwanted correction movements will ease intraoperative handling in general.

Changes in monocytic expression of aminopeptidase N/CD13 after major trauma

HLA-DR expression on monocytes as marker for monocytic function is severely depressed after major trauma. The membrane enzyme aminopeptidase N/CD13 can trigger help in antigen processing by MHC class II molecules of antigen-presenting cells. We determined the simultaneous expression of HLA-DR and CD13 on peripheral blood monocytes of patients with major trauma (injury severity score of > or =16). 1 : 1 conjugates of phycoerythrin (PE)-to-monoclonal antibody were used in combination with QuantiBRITE PE beads for a standardized quantification in terms of antibodies bound per cell (ABC). The very low expression of HLA-DR antigen on monocytes of patients at day 1 after major trauma confirmed previous results in the literature. Monocytic HLA-DR expression increased slowly to reach values in the lower range of healthy volunteers at day 14. Monocytic CD13 expression at day 1 showed values in the range of healthy volunteers, and a strong rise afterwards. Fourteen days after trauma, the monocytic expression of CD13 was still much higher than in the control group. Because lipopolysaccharide (LPS) and the anti-inflammatory cytokine interleukin (IL)-10 have been shown to be involved in the depressed HLA-DR expression on monocytes in trauma patients, we studied the in vitro effects of LPS and interleukin (IL)-10 on the expression of CD13 on monocytes prepared from the peripheral blood of healthy volunteers. Whereas a 3-day IL-10 treatment resulted in a down-regulation of both HLA-DR and CD13 expression on monocytes, LPS caused a down-regulation of HLA-DR but a rapid up-regulation of CD13 levels. Therefore we suggest that, with respect to monocytic CD13 expression, LPS rather than IL-10 could well be the explanation for monocytic surface molecules after severe injury, although other mediators with a CD13 regulating function have to be considered.