Prospective cohort study to determine if perioperative mortality at the University Teaching Hospital in Lusaka, Zambia has changed compared to historical data from 1987
Date
2019
Authors
Nchimunya, Henry
Journal Title
Journal ISSN
Volume Title
Publisher
The University of Zambia
Abstract
Despite low-income and middle-income countries (LMIC) being the regions of the world
with the greatest gap in access to safe surgical and anaesthetic services, there are fewer
published data for these countries on perioperative mortality indices. Global trends are that
perioperative mortality has declined over the last five decades. Zambia has had two
published studies over the last 30 years. The initial study conducted by Heywood, Wilson and
Sinclair in 1987 revealed an overall sixth day inpatient perioperative mortality rate (POMR)
of 7.55 per 1000 operations which was more than three times the current rate of high income
countries. Surgical avoidable POMR was highest at 1.93 per 1000 operations, followed by
administrative avoidable POMR at 0.85 per 1000 operations and then anaesthetic avoidable
POMR lowest at 0.53 per 1000 operations. Some of the recommendations from this study
resulted in the establishment of a trainining programme in anaesthesia and critical care, and
procurement of modern anaesthetic and monitoring equipment. It was the lack of more recent
knowledge to ascertain whether the quality of the Zambian surgical and anaesthetic services
have improved in keeping with global trends that made it imperative to conduct a
perioperative mortality study in the largest teaching hospital in Zambia as a follow up to the
initial study.
Over a six months period we prospectively identified all patients who died within six days of
surgery, having undergone a surgical procedure by either a general, regional or combined
anaesthesia at the University Teaching Hospital in Lusaka. All demised patients had their
records analysed by a specialist surgeon and anaesthetist to determine factors contributing to
their death by consensus. The causes of death were classified as avoidable, partially
avoidable and unavoidable. The deaths categorised as avoidable and partially avoidable were
further categorised into contributing factors, namely anaesthetic, surgical, administrative
cause or a combination thereof. The data on denomenator was collected from the surgical and
recovery room registers. The numerator was the total number of all inpatient deaths within
six days of the surgical procedure, with date of surgery being day one.
A total of 9775 cases were captured with 449 of these being lost to follow up. The
denominator was therefore made of 9326 cases. Seventy nine patients were detected to have
died during the study period. The overall sixth day inpatient perioperative mortality rate
(overall POMR) was found to be 0.85% (95% CI: 0.68-1.06) and the sixth day inpatient
avoidable mortality rate (avoidable POMR) was found to be 0.42% (95% CI: 0.30-0.57). The
sixth day inpatient anaesthetic POMR, surgical POMR and administrative POMR were found
to be 0.04% (95% CI: 0.01-0.079), 0.19% (95% CI: 0.12-0.31) and 0.19% (95% CI: 0.12-
0.31) respectively. Compared to the historical indices from 1987 by Heywood, Wilson and
Sinclair the chi-square test revealed a difference of no statistical significance (x2=0.411 with
1df, p=0.522). With regard to the 24 hour inpatient perioperative mortality indices, the
overall POMR was found to be 0.30% (95% CI: 0.21-0.44). The 24hr inpatient avoidable
mortality rate (avoidable POMR) was 0.17% (95% CI: 0.10-0.28). The 24hr inpatient
anaesthetic, surgical and administrative avoidable POMR were 0.02% (95% CI: 0.00-0.08),
0.07% (95% CI 0.03-0.16) and 0.08% (95% CI: 0.03-0.16) respectively.
The perioperative mortality indices at UTH have not reduced in comparison to the historical
data from 30 years ago. This is contrary to global indices which have shown a downward
trend over the last five decades.
Keywords: perioperative, mortality, numerator, denominator, avoidable
Description
Thesis
Keywords
Perioperative mortality--Zambia , Anaesthetic and monitoring equipment--Zambia