Safe Use Of High-Flow Nasal Oxygen (HFNO)

The Anesthesia Patient Safety Foundation provide an excellent overview of the popular and expanding use of High Flow Nasal Oxygen (HFNO), devices which are in many cases supplanting BIPAP, and  used to provide apneic ventilation during intubation, as well as post extubation and weaning from ventilation. This review also adds some caution, in particular the danger of fire, and contraindications.



Post-Dural Puncture Headache

A small study based on chart reviews limits the findings of this study which should be tested in future controlled studies. Nonetheless an interesting approach to postdural puncture headache was performed in the form of a topical sphenopalatine ganglion block and compared to the standard epidural blood patch. This ganglion block is being tested for migraine and other headaches but remains investigational.  (These topical blocks are usually described as simply placing local anesthetic soaked swabs along the floor of the nose until reaching and stopping at the nasopharynx and left there for 10mins or so, more recently with syringes attached to nasal catheter).

These authors found a faster headache resolution at 30 and 60 minutes with sphenopalatine block.



Graduated Compression Stockings and DVT

The Cochrane group weigh in on the common thromboembolism deterrent (TED), or graduated compression  stockings (GCS).

The evidence is supportive in surgical patients, not so clear in the medical setting.

“There is high‐quality evidence that GCS are effective in reducing the risk of DVT in hospitalised patients who have undergone general and orthopaedic surgery, with or without other methods of background thromboprophylaxis, where clinically appropriate. There is moderate‐quality evidence that GCS probably reduce the risk of proximal DVT, and low‐quality evidence that GCS may reduce the risk of PE. However, there remains a paucity of evidence to assess the effectiveness of GCS in diminishing the risk of DVT in medical patients”.



Hydroxyethyl Starch Discontinuance and CABG Outcome

This study reflects the shift away from colloids, in particular Hydroxyethyl Starch (HES), due to its association with adverse outcomes particularly in sepsis and renal dysfunction. Its use during surgery has persisted somewhat, with evidence of improved or no different outcomes using HES in abdominal surgery, not necessarily translatable to cardiac or critical care settings.

While suffering from retrospective limitations, this study showed that “for patients undergoing CABG on CPB, disinvestment in HES was associated with a reduced length of hospital stay and reduced blood product transfusion, without measurable change in death, renal failure, or dialysis rate. This association suggests that the continued use of HES in the cardiac surgical setting should be carefully reconsidered”.

Cost savings is another advantage, and many would advocate removing HES from anesthesia carts, suggested in a correspondence in the same journal (CJA)



Crystalloids, Colloids and Renal / Disability Outcome

Colloids have been out of fashion due to evidence of increased renal injury and mortality in the critically ill. However, some studies have failed to demonstrate harm in surgical patients.

This 1 year follow up study shows that in patients undergoing major open abdominal surgery, “there was no evidence of a statistically significant difference in long-term renal function between a balanced hydroxyethyl starch and a balanced crystalloid solution used as part of intraoperative goal-directed fluid therapy, although there was only limited power to rule out a clinically significant difference. However, disability-free survival was significantly higher in the colloid than in the crystalloid group”.

The study was fairly small, and baseline WHODAS (disability) scores were not available, and the study may not be applicable to those with pre-existing renal impairment. Goal-directed pulse contour analysis was used to guide fluid administration, not universally available. Nonetheless, the eternal crystalloid-colloid debate continues!



Propofol vs. Inhalational Anesthesia

A systematic review and meta-analysis finds that Propofol anesthesia provides better patient satisfaction, pain scores and an especially better nausea and vomiting outcome as compared with inhalational anesthesia, with a marginal increase in time for respiratory recovery and extubation.

While some recent studies have yielded opposing results on the effect of total intravenous anesthesia on cancer recurrence and mortality, there seems ample reason to choose Propofol based anesthesia. Further prospective validating studies are suggested.



National Emergency Laparotomy Audit (NELA)

The National Emergency Laparotomy Audit (NELA)  2016-2017 is released and provides information on how performance in England and Wales matches benchmarks, and how institutions can compare their performance.

Overall, compared with 2013:

  • hospital stays are about 15 days (4 days less)
  • 30 day mortality 9.5% (down from 11.8%)
  • 87% received a pre-operative CT Scan (up from 80%)
  • One year mortality was 77%, and three year mortality 66%
  • 75% of patients now receive an assessment of risk (up from 71% last year, and 56% in Year 1).

More negative findings were:

  • 76% of patients with sepsis did not receive antibiotics in the one-hour time frame.
  • 77% did not receive geriatric consult even though half were over 70 years old
  • 27% of patients needing the most urgent surgery did not get to the Operating Room in the recommended timeframes
  • Only 66% of consultant anesthesiologists and surgeons (attending physicians) were present in the OR after hours, and 90% during daytime.

NELA Recommendations include:

1. improving outcomes and reducing complications
2. ensuring all patients receive an assessment of their risk of death
3. delivering care within agreed timeframes for all patients
4. enabling consultant input in the perioperative period for all high risk patients
5. effective multidisciplinary working
6. supporting quality improvement.



Acupuncture for Post-Operative Nausea and Vomiting

Acupuncture has long been used for nausea and vomiting in different scenarios using the P6 point on the anterior forearm above the wrist. Studies have always been lower quality, with study blinding issues and  sham acupuncture being potentially effective also. A Cochrane review nonetheless concluded it to be comparable  to anti-emetics ( link ).

This latest study finds a significant reduction in nausea (more than vomiting) in the recovery period even when added to anti-emetics. The study was in children 3-9 years of age undergoing adenotonsillectomy. All patients received Ondansetron and Dexamethasone. There was no difference after 24 hours.

P6 acupuncture appears a simple measure without significant side-effects to consider for post-operative nausea and vomiting prevention.




Time of Day and Emergency Surgery Mortality

Some studies have suggested worse outcomes and higher mortality in surgery after hours and in particular at weekends, although others did not corroborate  (see ‘weekend effect’ link ). One of the postulated mechanisms is fewer resources, staff and backup.

This single center study was in emergency surgery and did not identify an association of time of emergency surgery, categorised into one of three epochs (day, evening and night) with death up to 30 postoperative days. They do advise further larger studies with longer follow up to verify these findings. A large and sometimes disparate mix of emergencies including general, neuro, Cesarean under regional and sedation-only was studied  with minimal comorbidity information other than ASA status.




ECMO for Cardiac Arrest

Refractory cardiac arrest was defined as no return of spontaneous circulation after 30mins of CPR.

This was a small observational study of 23 patients suffering cardiac arrest in the Operating Room who underwent extracorporeal cardiopulmonary resuscitation. The survival rates of neurologically‐intact subjects were 9/23 (39%) and 6/23 (26%) at 24 hours postoperatively and at hospital discharge, respectively.The main cause was hemorrhagic shock and 23% of these were discharged neurologically intact.

Where available, extracorporeal cardiopulmonary resuscitation is suggested as an option for refractory cardiac arrest in the OR due to hemorrhage.